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CHEMISTRY (616 journals)                  1 2 3 4 | Last

Showing 1 - 200 of 735 Journals sorted alphabetically
2D Materials     Hybrid Journal   (Followers: 14)
Accreditation and Quality Assurance: Journal for Quality, Comparability and Reliability in Chemical Measurement     Hybrid Journal   (Followers: 26)
ACS Catalysis     Full-text available via subscription   (Followers: 43)
ACS Chemical Neuroscience     Full-text available via subscription   (Followers: 21)
ACS Combinatorial Science     Full-text available via subscription   (Followers: 21)
ACS Macro Letters     Full-text available via subscription   (Followers: 26)
ACS Medicinal Chemistry Letters     Full-text available via subscription   (Followers: 41)
ACS Nano     Full-text available via subscription   (Followers: 275)
ACS Photonics     Full-text available via subscription   (Followers: 14)
ACS Synthetic Biology     Full-text available via subscription   (Followers: 24)
Acta Chemica Iasi     Open Access   (Followers: 3)
Acta Chimica Sinica     Full-text available via subscription   (Followers: 2)
Acta Chimica Slovaca     Open Access   (Followers: 2)
Acta Chimica Slovenica     Open Access   (Followers: 1)
Acta Chromatographica     Full-text available via subscription   (Followers: 9)
Acta Facultatis Medicae Naissensis     Open Access  
Acta Metallurgica Sinica (English Letters)     Hybrid Journal   (Followers: 7)
Acta Scientifica Naturalis     Open Access   (Followers: 3)
adhäsion KLEBEN & DICHTEN     Hybrid Journal   (Followers: 6)
Adhesion Adhesives & Sealants     Hybrid Journal   (Followers: 9)
Adsorption Science & Technology     Full-text available via subscription   (Followers: 6)
Advanced Functional Materials     Hybrid Journal   (Followers: 57)
Advanced Science Focus     Free   (Followers: 5)
Advances in Chemical Engineering and Science     Open Access   (Followers: 66)
Advances in Chemical Science     Open Access   (Followers: 16)
Advances in Chemistry     Open Access   (Followers: 20)
Advances in Colloid and Interface Science     Full-text available via subscription   (Followers: 19)
Advances in Drug Research     Full-text available via subscription   (Followers: 21)
Advances in Enzyme Research     Open Access   (Followers: 9)
Advances in Fluorine Science     Full-text available via subscription   (Followers: 7)
Advances in Fuel Cells     Full-text available via subscription   (Followers: 15)
Advances in Heterocyclic Chemistry     Full-text available via subscription   (Followers: 9)
Advances in Materials Physics and Chemistry     Open Access   (Followers: 25)
Advances in Nanoparticles     Open Access   (Followers: 15)
Advances in Organometallic Chemistry     Full-text available via subscription   (Followers: 15)
Advances in Polymer Science     Hybrid Journal   (Followers: 43)
Advances in Protein Chemistry     Full-text available via subscription   (Followers: 17)
Advances in Protein Chemistry and Structural Biology     Full-text available via subscription   (Followers: 18)
Advances in Quantum Chemistry     Full-text available via subscription   (Followers: 6)
Advances in Science and Technology     Full-text available via subscription   (Followers: 12)
African Journal of Bacteriology Research     Open Access  
African Journal of Chemical Education     Open Access   (Followers: 3)
African Journal of Pure and Applied Chemistry     Open Access   (Followers: 7)
Agrokémia és Talajtan     Full-text available via subscription   (Followers: 2)
Al-Kimia : Jurnal Penelitian Sains Kimia     Open Access  
Alkaloids: Chemical and Biological Perspectives     Full-text available via subscription   (Followers: 2)
AMB Express     Open Access   (Followers: 1)
Ambix     Hybrid Journal   (Followers: 3)
American Journal of Biochemistry and Biotechnology     Open Access   (Followers: 62)
American Journal of Biochemistry and Molecular Biology     Open Access   (Followers: 15)
American Journal of Chemistry     Open Access   (Followers: 29)
American Journal of Plant Physiology     Open Access   (Followers: 11)
American Mineralogist     Hybrid Journal   (Followers: 15)
Analyst     Full-text available via subscription   (Followers: 38)
Angewandte Chemie     Hybrid Journal   (Followers: 165)
Angewandte Chemie International Edition     Hybrid Journal   (Followers: 244)
Annales UMCS, Chemia     Open Access  
Annals of Clinical Chemistry and Laboratory Medicine     Open Access   (Followers: 5)
Annual Reports in Computational Chemistry     Full-text available via subscription   (Followers: 3)
Annual Reports Section A (Inorganic Chemistry)     Full-text available via subscription   (Followers: 4)
Annual Reports Section B (Organic Chemistry)     Full-text available via subscription   (Followers: 9)
Annual Review of Chemical and Biomolecular Engineering     Full-text available via subscription   (Followers: 12)
Annual Review of Food Science and Technology     Full-text available via subscription   (Followers: 13)
Anti-Infective Agents     Hybrid Journal   (Followers: 3)
Antiviral Chemistry and Chemotherapy     Hybrid Journal   (Followers: 1)
Applied Organometallic Chemistry     Hybrid Journal   (Followers: 8)
Applied Spectroscopy     Full-text available via subscription   (Followers: 22)
Applied Surface Science     Hybrid Journal   (Followers: 31)
Arabian Journal of Chemistry     Open Access   (Followers: 5)
ARKIVOC     Open Access   (Followers: 1)
Asian Journal of Biochemistry     Open Access   (Followers: 1)
Atomization and Sprays     Full-text available via subscription   (Followers: 4)
Australian Journal of Chemistry     Hybrid Journal   (Followers: 7)
Autophagy     Hybrid Journal   (Followers: 2)
Avances en Quimica     Open Access  
Biochemical Pharmacology     Hybrid Journal   (Followers: 10)
Biochemistry     Full-text available via subscription   (Followers: 341)
Biochemistry Insights     Open Access   (Followers: 6)
Biochemistry Research International     Open Access   (Followers: 6)
BioChip Journal     Hybrid Journal  
Bioinorganic Chemistry and Applications     Open Access   (Followers: 9)
Bioinspired Materials     Open Access   (Followers: 5)
Biointerface Research in Applied Chemistry     Open Access   (Followers: 2)
Biointerphases     Open Access   (Followers: 1)
Biology, Medicine, & Natural Product Chemistry     Open Access   (Followers: 1)
Biomacromolecules     Full-text available via subscription   (Followers: 21)
Biomass Conversion and Biorefinery     Partially Free   (Followers: 10)
Biomedical Chromatography     Hybrid Journal   (Followers: 7)
Biomolecular NMR Assignments     Hybrid Journal   (Followers: 3)
BioNanoScience     Partially Free   (Followers: 5)
Bioorganic & Medicinal Chemistry     Hybrid Journal   (Followers: 122)
Bioorganic & Medicinal Chemistry Letters     Hybrid Journal   (Followers: 84)
Bioorganic Chemistry     Hybrid Journal   (Followers: 10)
Biopolymers     Hybrid Journal   (Followers: 18)
Biosensors     Open Access   (Followers: 2)
Biotechnic and Histochemistry     Hybrid Journal   (Followers: 2)
Bitácora Digital     Open Access  
Boletin de la Sociedad Chilena de Quimica     Open Access  
Bulletin of the Chemical Society of Ethiopia     Open Access   (Followers: 2)
Bulletin of the Chemical Society of Japan     Full-text available via subscription   (Followers: 24)
Bulletin of the Korean Chemical Society     Hybrid Journal   (Followers: 1)
C - Journal of Carbon Research     Open Access   (Followers: 3)
Cakra Kimia (Indonesian E-Journal of Applied Chemistry)     Open Access  
Canadian Association of Radiologists Journal     Full-text available via subscription   (Followers: 2)
Canadian Journal of Chemistry     Hybrid Journal   (Followers: 10)
Canadian Mineralogist     Full-text available via subscription   (Followers: 6)
Carbohydrate Research     Hybrid Journal   (Followers: 26)
Carbon     Hybrid Journal   (Followers: 71)
Catalysis for Sustainable Energy     Open Access   (Followers: 7)
Catalysis Reviews: Science and Engineering     Hybrid Journal   (Followers: 7)
Catalysis Science and Technology     Free   (Followers: 8)
Catalysis Surveys from Asia     Hybrid Journal   (Followers: 3)
Catalysts     Open Access   (Followers: 9)
Cellulose     Hybrid Journal   (Followers: 7)
Cereal Chemistry     Full-text available via subscription   (Followers: 4)
ChemBioEng Reviews     Full-text available via subscription   (Followers: 1)
ChemCatChem     Hybrid Journal   (Followers: 8)
Chemical and Engineering News     Free   (Followers: 18)
Chemical Bulletin of Kazakh National University     Open Access  
Chemical Communications     Full-text available via subscription   (Followers: 73)
Chemical Engineering Research and Design     Hybrid Journal   (Followers: 26)
Chemical Research in Chinese Universities     Hybrid Journal   (Followers: 3)
Chemical Research in Toxicology     Full-text available via subscription   (Followers: 22)
Chemical Reviews     Full-text available via subscription   (Followers: 186)
Chemical Science     Open Access   (Followers: 23)
Chemical Technology     Open Access   (Followers: 22)
Chemical Vapor Deposition     Hybrid Journal   (Followers: 5)
Chemical Week     Full-text available via subscription   (Followers: 7)
Chemie in Unserer Zeit     Hybrid Journal   (Followers: 56)
Chemie-Ingenieur-Technik (Cit)     Hybrid Journal   (Followers: 24)
ChemInform     Hybrid Journal   (Followers: 8)
Chemistry & Biodiversity     Hybrid Journal   (Followers: 7)
Chemistry & Biology     Full-text available via subscription   (Followers: 32)
Chemistry & Industry     Hybrid Journal   (Followers: 6)
Chemistry - A European Journal     Hybrid Journal   (Followers: 160)
Chemistry - An Asian Journal     Hybrid Journal   (Followers: 16)
Chemistry and Materials Research     Open Access   (Followers: 20)
Chemistry Central Journal     Open Access   (Followers: 4)
Chemistry Education Research and Practice     Free   (Followers: 5)
Chemistry in Education     Open Access   (Followers: 9)
Chemistry International     Hybrid Journal   (Followers: 2)
Chemistry Letters     Full-text available via subscription   (Followers: 44)
Chemistry of Materials     Full-text available via subscription   (Followers: 252)
Chemistry of Natural Compounds     Hybrid Journal   (Followers: 9)
Chemistry World     Full-text available via subscription   (Followers: 19)
Chemistry-Didactics-Ecology-Metrology     Open Access   (Followers: 1)
ChemistryOpen     Open Access   (Followers: 1)
Chemkon - Chemie Konkret, Forum Fuer Unterricht Und Didaktik     Hybrid Journal  
Chemoecology     Hybrid Journal   (Followers: 4)
Chemometrics and Intelligent Laboratory Systems     Hybrid Journal   (Followers: 14)
Chemosensors     Open Access  
ChemPhysChem     Hybrid Journal   (Followers: 11)
ChemPlusChem     Hybrid Journal   (Followers: 2)
ChemTexts     Hybrid Journal  
CHIMIA International Journal for Chemistry     Full-text available via subscription   (Followers: 2)
Chinese Journal of Chemistry     Hybrid Journal   (Followers: 6)
Chinese Journal of Polymer Science     Hybrid Journal   (Followers: 11)
Chromatographia     Hybrid Journal   (Followers: 24)
Chromatography     Open Access   (Followers: 2)
Chromatography Research International     Open Access   (Followers: 6)
Clay Minerals     Full-text available via subscription   (Followers: 10)
Cogent Chemistry     Open Access  
Colloid and Interface Science Communications     Open Access  
Colloid and Polymer Science     Hybrid Journal   (Followers: 11)
Colloids and Interfaces     Open Access  
Colloids and Surfaces B: Biointerfaces     Hybrid Journal   (Followers: 6)
Combinatorial Chemistry & High Throughput Screening     Hybrid Journal   (Followers: 5)
Combustion Science and Technology     Hybrid Journal   (Followers: 22)
Comments on Inorganic Chemistry: A Journal of Critical Discussion of the Current Literature     Hybrid Journal   (Followers: 2)
Composite Interfaces     Hybrid Journal   (Followers: 7)
Comprehensive Chemical Kinetics     Full-text available via subscription   (Followers: 1)
Comptes Rendus Chimie     Full-text available via subscription  
Comptes Rendus Physique     Full-text available via subscription   (Followers: 1)
Computational and Theoretical Chemistry     Hybrid Journal   (Followers: 9)
Computational Biology and Chemistry     Hybrid Journal   (Followers: 11)
Computational Chemistry     Open Access   (Followers: 2)
Computers & Chemical Engineering     Hybrid Journal   (Followers: 10)
Coordination Chemistry Reviews     Full-text available via subscription   (Followers: 3)
Copernican Letters     Open Access   (Followers: 1)
Corrosion Series     Full-text available via subscription   (Followers: 6)
Critical Reviews in Biochemistry and Molecular Biology     Hybrid Journal   (Followers: 5)
Croatica Chemica Acta     Open Access  
Crystal Structure Theory and Applications     Open Access   (Followers: 4)
CrystEngComm     Full-text available via subscription   (Followers: 13)
Current Catalysis     Hybrid Journal   (Followers: 2)
Current Chromatography     Hybrid Journal  
Current Green Chemistry     Hybrid Journal  
Current Metabolomics     Hybrid Journal   (Followers: 5)
Current Microwave Chemistry     Hybrid Journal  
Current Opinion in Colloid & Interface Science     Hybrid Journal   (Followers: 9)
Current Opinion in Molecular Therapeutics     Full-text available via subscription   (Followers: 14)
Current Research in Chemistry     Open Access   (Followers: 8)
Current Science     Open Access   (Followers: 69)
Current Trends in Biotechnology and Chemical Research     Open Access   (Followers: 3)
Dalton Transactions     Full-text available via subscription   (Followers: 23)
Detection     Open Access   (Followers: 2)
Developments in Geochemistry     Full-text available via subscription   (Followers: 2)
Diamond and Related Materials     Hybrid Journal   (Followers: 12)
Dislocations in Solids     Full-text available via subscription  
Doklady Chemistry     Hybrid Journal  

        1 2 3 4 | Last

Journal Cover Chemical Engineering Research and Design
  [SJR: 0.873]   [H-I: 65]   [26 followers]  Follow
   Hybrid Journal Hybrid journal (It can contain Open Access articles)
   ISSN (Print) 0263-8762 - ISSN (Online) 0263-8762
   Published by Elsevier Homepage  [3177 journals]
  • Effect of mixing conditions on the wet preparation of ceramic foams
    • Authors: A. Celani; S. Blackburn; M.J.H. Simmons; E.H. Stitt
      Pages: 1 - 14
      Abstract: Publication date: June 2018
      Source:Chemical Engineering Research and Design, Volume 134
      Author(s): A. Celani, S. Blackburn, M.J.H. Simmons, E.H. Stitt
      Ceramic foams are a promising alternative to conventional catalyst supports due to their macro-porosity, which should enhance mass transport properties during reactions. Whilst direct foaming is a straightforward production method, the use of kitchen mixers commonly reported in the literature to initially froth the ceramic slurry limits understanding of scale-up. This study reports a systematic experimental investigation of the impact of mixing parameters on the properties of the foams produced in an agitated baffled vessel of diameter, T=175mm, equipped with an up-pumping pitch blade turbine with diameter of either D=0.23T or 0.51T and a bottom round sparger with a diameter of 45mm. The flow conditions in the present study were in the low to mid transitional regime (50<Re<1000). Design of Experiments (DoE) was employed to generate a series of screening experiments by variation of sparging time, air flow rate, impeller speed and impeller diameter. The mixing behaviour was described as a function of relevant dimensionless groups (Re, Fr, Flg, etc.) whilst the gas–liquid flow regime was estimated by examination of a ceramic particles free system. The properties of the foams obtained were correlated with key dimensionless numbers, though the exponents obtained deviated from values in the published literature. In addition, the rheology of the foam was correlated to the bubble size distribution showing that rheology measurements have potential for at-line measurement to control the structure of the produced material.

      PubDate: 2018-04-16T05:12:41Z
      DOI: 10.1016/j.cherd.2018.03.044
      Issue No: Vol. 134 (2018)
  • An analysis of the mini-tablet fluidized bed coating process
    • Authors: Rok Šibanc; Magdalena Turk; Rok Dreu
      Pages: 15 - 25
      Abstract: Publication date: June 2018
      Source:Chemical Engineering Research and Design, Volume 134
      Author(s): Rok Šibanc, Magdalena Turk, Rok Dreu
      Mini-tablets with diameters of 2.0, 2.5, and 3.0mm are coated in two different lab-scale fluidized bed coaters equipped with a Wurster draft tube. The main focus of the research is to evaluate the inter-particle coating variability, and to assess the contribution of cycle time variation. Cycle times are measured using a photoluminescent tracer with a detector mounted on the top of the draft tube. The number of passes variability is represented from 5 to 28% of the total coating variability. Additionally, transmittance measurements at the top of the Wurster draft tube are performed in order to assess the inter-particle sheltering effects. Transmittance results are correlated to the amount of coating deposited per single pass of the spray zone and are converted to solids volume fractions. The dynamics of the transmittance signal further reveal the persistence of a particle arrangement within the draft tube of the two different coaters. The gathered results give insight into the different performance of two fluidized bed coaters in terms of inter-particle coating variability.

      PubDate: 2018-04-16T05:12:41Z
      DOI: 10.1016/j.cherd.2018.03.020
      Issue No: Vol. 134 (2018)
  • Multi-stage granulation: An approach to enhance final granule attributes
    • Authors: Ali Z. Al hassn; Sonja Jeßberger; Michael J. Hounslow; Agba D. Salman
      Pages: 26 - 35
      Abstract: Publication date: June 2018
      Source:Chemical Engineering Research and Design, Volume 134
      Author(s): Ali Z. Al hassn, Sonja Jeßberger, Michael J. Hounslow, Agba D. Salman
      A new method in a high shear wet granulation process was implemented to enhance the final granule attributes. The granulation process in this method is divided into stages. In each stage different impeller speed was used. For this reason, this method of wet granulation is named here as multi-stage granulation (MSG) to be distinguish from the normal granulation (NG) in which the impeller speed is fixed throughout the granulation process. The experimental work revealed that by following the multi-stage granulation a noticeable change in the granules attributes has been observed. In this work, a high shear mixer (Eirich EL1) has been used. Calcium carbonate and melted polyethylene glycol (PEG1000) were used as a primary powder and binder respectively. The speed of impeller has been changed in a pulse mode throughout the granulation process from moderate speed to high speed in different intervals of time. Analysis of the produced granules showed that the granule characteristics with the multi-stage granulation were different to that with the normal granulation process. The granule median size affected clearly during the process. However, the granule porosity did not influence enormously during the process. The surface area of the granules also increased to some extent after the pulse change in the impeller speed. This increase in the surface area is reflected on the granules dissolution process. The collected granules after the pulse change were dissolving a slightly faster than the granule samples before the pulse change. This may due to the increase in the surface area of the granules.
      Graphical abstract image

      PubDate: 2018-04-16T05:12:41Z
      DOI: 10.1016/j.cherd.2018.03.038
      Issue No: Vol. 134 (2018)
  • Optimization of steady-state and dynamic performances of water–gas shift
           reaction in membrane reactor
    • Authors: Shuey Z. Saw; Jobrun Nandong; Ujjal K. Ghosh
      Pages: 36 - 51
      Abstract: Publication date: June 2018
      Source:Chemical Engineering Research and Design, Volume 134
      Author(s): Shuey Z. Saw, Jobrun Nandong, Ujjal K. Ghosh
      Membrane rector technology has been increasingly recognized as a promising solution to produce high-purity hydrogen and to support future realization of hydrogen economy. Although some of the economic evaluations have shown that the inclusion of membrane reactor into an existing IGCC plant may be a viable option, it remains to be answered whether the added system can be easily controlled or not. This paper presents a feasibility study of four pre-defined membrane reactor flowsheets (including auxiliary units) based on nominal throughput 23,200t/day. The net present value (NPV) and v-gap metric are used as the economic and controllability performance criteria respectively. Considering uncertainties in future prices of hydrogen and electricity, the optimal NPV and v-gap metric are US$ 0.471 billion and 0.253 respectively. This suggests that the optimized membrane reactor flowsheet is feasible on the economic and controllability grounds.

      PubDate: 2018-04-16T05:12:41Z
      DOI: 10.1016/j.cherd.2018.03.045
      Issue No: Vol. 134 (2018)
  • Multilayer petal-like enzymatic-inorganic hybrid micro-spheres
           [CPO-(Cu/Co/Cd)3(PO4)2] with high bio-catalytic activity
    • Authors: Shengjie Wang; Yu Ding; Rui Chen; Mancheng Hu; Shuni Li; Quanguo Zhai; Yucheng Jiang
      Pages: 52 - 61
      Abstract: Publication date: June 2018
      Source:Chemical Engineering Research and Design, Volume 134
      Author(s): Shengjie Wang, Yu Ding, Rui Chen, Mancheng Hu, Shuni Li, Quanguo Zhai, Yucheng Jiang
      CPO, a versatile enzyme, has limitations in industrial applications due to its poor stability and the difficulty of reuse. The preparation of stable immobilized enzymes with high catalytic activity is therefore desirable, but remains a challenge. A facile preparation of a series of enzyme-inorganic hybrid micro-spheres [chloroperoxidase (CPO)-(Cu/Co/Cd)3(PO4)2] and its application in the decolorization of crystal violet is reported in this work. All the hybrid micro-spheres show a multilayer petal-like structure. The formation of hybrid micro-spheres were proposed via four stages: crystallization, in-situ coordination, self-assembly and size growth. The process was entropy-driven, and there was a competition between precipitation of phosphate and coordination of M2+ with amide groups of CPO. The introduction of excess of chloride ions retarded the phosphate from precipitating by forming [MCl4]2− complexes, while simultaneously promoting the coordination of M2+ with amide groups. These hybrid materials showed high bio-catalytic activity in the decolorization of crystal violet. The decolorization efficiency reached 99.66%, 98.44% and 98.05% just within 3min using CPO-Cu3(PO4)2, CPO-Cd3(PO4)2 and CPO-Co3(PO4)2 respectively. They also have good thermal stability, and can keep 52.89% catalytic activity after 8 cycles of use. CPO-inorganic hybrid micro-spheres [chloroperoxidase (CPO)-(Cu/Co/Cd)3(PO4)2] is promising in the treatment of waste water containing crystal violet. It also has potential application for treatment of other soluble organic dyes in industrial wastewater.
      Graphical abstract image

      PubDate: 2018-04-16T05:12:41Z
      DOI: 10.1016/j.cherd.2018.03.036
      Issue No: Vol. 134 (2018)
  • Optimal heat exchanger network synthesis based on improved cuckoo search
           via Lévy flights
    • Authors: Hongliang Zhang; Guomin Cui
      Pages: 62 - 79
      Abstract: Publication date: June 2018
      Source:Chemical Engineering Research and Design, Volume 134
      Author(s): Hongliang Zhang, Guomin Cui
      Heat exchanger network synthesis (HENS) is still a challenging task for minimizing the Total Annual Cost (TAC). In this work, a Cuckoo Search Algorithm (CSA) is introduced to solve the NonLinear Programming (NLP) problem of the fixed heat exchanger network design to determine the optimal heat load distribution, which can help improve the heat load configurations of previously found optimum configurations. The improved CSA (ICSA) is used to solve the Mixed Integer NonLinear Programming (MINLP) problem for optimal HENS, which can simultaneously optimize continuous and integer variables, and the proposed stream arrangement strategy aims to optimize the stream match search space by lowering the stage demands, i.e. reducing the number of independent variables, which is a promising means for an easier solution of large and medium sized HENS problems. Four large and medium sized benchmark cases have been investigated, obtaining no-splits results with lower TAC in a shorter computational time. In addition, a special feature from case 3 and 4 is analyzed, which is useful in order to achieve a lower TAC by using modified Stage-Wise Superstructure (SWS) models with flexible utility placement.

      PubDate: 2018-04-16T05:12:41Z
      DOI: 10.1016/j.cherd.2018.03.046
      Issue No: Vol. 134 (2018)
  • An innovative bioprocess for methane conversion to methanol using an
           efficient methane transfer chamber coupled with an airlift bioreactor
    • Authors: Mohammad Ali Ghaz-Jahanian; Ali Baradar Khoshfetrat; Maliheh Hosseinian Rostami; Mohammad Haghighi Parapari
      Pages: 80 - 89
      Abstract: Publication date: June 2018
      Source:Chemical Engineering Research and Design, Volume 134
      Author(s): Mohammad Ali Ghaz-Jahanian, Ali Baradar Khoshfetrat, Maliheh Hosseinian Rostami, Mohammad Haghighi Parapari
      Biosynthesis of methanol from methane as a direct method takes place at ambient temperature and pressure which causes a considerable reduction in process costs. In this study an efficient methane transfer chamber along with an external-loop airlift bioreactor were developed to dissolve methane and oxygen in the culture separately. Mass transfer coefficients for oxygen in the bioreactor and methane in the transfer chamber were obtained 97.2h−1 and 70.8h−1 respectively. Two strains of methanotroph bacteria (AS1 and AS2) were also isolated from activated sludge. Factorial design of experiments for operational parameters showed a maximum productivity for AS1 strain at 28°C when using nitrate as nitrogen source. Batch runs in airlift bioreactor using the AS1 strain and optimized operating parameters represented a peak of 1600mg/L in methanol synthesis during the first 3:30h without using inhibitor for methanol dehydrogenase (MDH) enzyme. Sequencing batch process, at the next step, was used to create intermediate lag phase and to increase the stability of microorganisms by forming flocs. The results of this study cleared that the designed system is safe and efficient to scale-up, and it can be considered as a potential alternative method in the production of methanol.
      Graphical abstract image

      PubDate: 2018-04-25T05:26:41Z
      DOI: 10.1016/j.cherd.2018.03.039
      Issue No: Vol. 134 (2018)
  • An outlook towards hydrogen supply chain networks in 2050 — Design of
           novel fuel infrastructures in Germany
    • Authors: Anton Ochoa Bique; Edwin Zondervan
      Pages: 90 - 103
      Abstract: Publication date: June 2018
      Source:Chemical Engineering Research and Design, Volume 134
      Author(s): Anton Ochoa Bique, Edwin Zondervan
      This work provides a comprehensive investigation of the feasibility of hydrogen as transportation fuel from a supply chain point of view. It introduces an approach for the identification the best hydrogen infrastructure pathways making decision of primary energy source, production, storage and distribution networks to aid the target of greenhouse gas emissions reduction in Germany. The minimization of the total hydrogen supply chain (HSC) network cost for Germany in 2030 and 2050 years is the objective of this study. The model presented in this paper is expanded to take into account water electrolysis technology driven by solar and wind energy. Two scenarios are evaluated, including a full range of technologies and “green” technologies using only renewable resources. The resulting model is a mixed integer linear program (MILP) that is solved with the Advanced Integrated Multidimensional Modeling System (AIMMS). The results show that renewable energy as a power source has the potential to replace common used fossil fuel in the near future even though currently coal gasification technology is the still the dominant technology.

      PubDate: 2018-04-25T05:26:41Z
      DOI: 10.1016/j.cherd.2018.03.037
      Issue No: Vol. 134 (2018)
  • Process design and techno-economical analysis of hydrogen production by
           aqueous phase reforming of sorbitol
    • Authors: Dmitry A. Sladkovskiy; Lidia I. Godina; Kirill V. Semikin; Elena V. Sladkovskaya; Daria A. Smirnova; Dmitry Yu. Murzin
      Pages: 104 - 116
      Abstract: Publication date: June 2018
      Source:Chemical Engineering Research and Design, Volume 134
      Author(s): Dmitry A. Sladkovskiy, Lidia I. Godina, Kirill V. Semikin, Elena V. Sladkovskaya, Daria A. Smirnova, Dmitry Yu. Murzin
      The present study was focused on detailed sorbitol aqueous phase reforming (APR) process design. Aspen HYSYS software was used to design a 500kg/h hydrogen production plant operation with sorbitol syrup as a feedstock. For reactor modelling a complex reaction network was taken into account along with phase equilibrium simulations which determined to have a significant impact on the total process heat due to possibility of water evaporation. The model was adjusted and verified using the experimental data with 1%Pt/Al2O3. The process optimization has included several conceptual improvements such as middle pressure steam co-generation and hot water recycle which can significantly decrease the operation costs. The total costs of hydrogen were estimated as 12.97$/kg, where feedstock costs take the major contribution of 91.8%. The most feasible way of making APR economical attractive is production of polyols from the lignocellulosic biomass.
      Graphical abstract image

      PubDate: 2018-04-25T05:26:41Z
      DOI: 10.1016/j.cherd.2018.03.041
      Issue No: Vol. 134 (2018)
  • Structure of shear-enhanced flow on membrane surface with horizontal
           vibration and its effect on filtration performance
    • Authors: Kazutaka Takata; Katsuyoshi Tanida
      Pages: 130 - 139
      Abstract: Publication date: June 2018
      Source:Chemical Engineering Research and Design, Volume 134
      Author(s): Kazutaka Takata, Katsuyoshi Tanida
      Back-and-forth horizontal vibration of a membrane can produce a high shear rate in fluid near a membrane surface. The present study investigated the relationship between the flow structure near the membrane surface and the characteristics of separation performance. A numerical calculation was performed to analyze the flow field near the membrane surface. Results revealed that the velocity of fluid near the membrane surface lags that of the membrane. The delay depends on the magnitudes of the inertia and viscosity of the fluid. Additionally, the thickness of the velocity boundary layer on the membrane surface obtained from numerical calculation was found to be identical to that provided by the boundary layer theory of horizontal vibration. Furthermore, the permeate flux measured using emulsion solution was well correlated with the shear rate as a function of amplitude and frequency.

      PubDate: 2018-04-25T05:26:41Z
      DOI: 10.1016/j.cherd.2018.03.042
      Issue No: Vol. 134 (2018)
  • Robust state estimation of feeding–blending systems in continuous
           pharmaceutical manufacturing
    • Authors: Jianfeng Liu; Qinglin Su; Mariana Moreno; Carl Laird; Zoltan Nagy; Gintaras Reklaitis
      Pages: 140 - 153
      Abstract: Publication date: June 2018
      Source:Chemical Engineering Research and Design, Volume 134
      Author(s): Jianfeng Liu, Qinglin Su, Mariana Moreno, Carl Laird, Zoltan Nagy, Gintaras Reklaitis
      State estimation is a fundamental part of monitoring, control, and real-time optimization in continuous pharmaceutical manufacturing. For nonlinear dynamic systems with hard constraints, moving horizon estimation (MHE) can estimate the current state by solving a well-defined optimization problem where process complexities are explicitly considered as constraints. Traditional MHE techniques assume random measurement noise governed by some normal distributions. However, state estimates can be unreliable if noise is not normally distributed or measurements are contaminated with gross or systematic errors. To improve the accuracy and robustness of state estimation, we incorporate robust estimators within the standard MHE skeleton, leading to an extended MHE framework. The proposed MHE approach is implemented on two pharmaceutical continuous feeding–blending system (FBS) configurations which include loss-in-weight (LIW) feeders and continuous blenders. Numerical results show that our MHE approach is robust to gross errors and can provide reliable state estimates when measurements are contaminated with outliers and drifts. Moreover, the efficient solution of the MHE realized in this work, suggests feasible application of on-line state estimation on more complex continuous pharmaceutical processes.

      PubDate: 2018-04-25T05:26:41Z
      DOI: 10.1016/j.cherd.2018.03.017
      Issue No: Vol. 134 (2018)
  • Optimization-based design of crude oil distillation units using surrogate
           column models and a support vector machine
    • Authors: Dauda Ibrahim; Megan Jobson; Jie Li; Gonzalo Guillén-Gosálbez
      Pages: 212 - 225
      Abstract: Publication date: June 2018
      Source:Chemical Engineering Research and Design, Volume 134
      Author(s): Dauda Ibrahim, Megan Jobson, Jie Li, Gonzalo Guillén-Gosálbez
      This paper presents a novel optimization-based approach for the design of heat-integrated crude oil distillation units, which are widely used in refineries. The methodology presented combines, within a unified framework, surrogate distillation column models based on artificial neural networks, feasibility constraints constructed using a support vector machine, and pinch analysis to maximize heat recovery, in order to optimize the distillation column configuration and its operating conditions. The inputs to the surrogate column model are given by the column structure and operating conditions, while the outputs are related to the column performance. The support vector machine classifier filters infeasible design alternatives from the search space, thus reducing computational time, and ultimately improves the quality of the final solution. The overall optimization problem takes the form of a mixed-integer nonlinear program, which is solved by a genetic algorithm that seeks the design and operating variables values that minimize the total annualized cost. The capabilities of the proposed approach are illustrated using an industrially–relevant case study. Numerical results show that promising design alternatives can be obtained using the proposed method. The approach can help engineers to design and operate petroleum refineries optimally, where these are expected to continue to play a major role in the energy mix for some years.

      PubDate: 2018-04-25T05:26:41Z
      DOI: 10.1016/j.cherd.2018.03.006
      Issue No: Vol. 134 (2018)
  • Real-time furnace balancing of steam methane reforming furnaces
    • Authors: Anh Tran; Madeleine Pont; Marquis Crose; Panagiotis D. Christofides
      Pages: 238 - 256
      Abstract: Publication date: June 2018
      Source:Chemical Engineering Research and Design, Volume 134
      Author(s): Anh Tran, Madeleine Pont, Marquis Crose, Panagiotis D. Christofides
      This paper focuses on the development of a real-time furnace-balancing scheme for a reformer at a centralized hydrogen facility using steam methane reforming (SMR) technology so that the reformer fuel input can be optimized in real-time to increase the plant throughput and to reject operational disturbances associated with flow control valves. Initially, the framework for the furnace-balancing scheme, the statistical-based model identification and the valve-to-flow-rate converter developed in Tran et al. (2017a, 2018) are integrated with a heuristic search algorithm to create a real-time balancing procedure, which recursively calculates different total fuel flow rates of which the respective spatial distribution to burners is optimized until key operational specifications, e.g., the reformer throughput is maximized, and the outer tube wall temperature (OTWT) along the reforming tube length of all reforming tubes must not exceed the design temperature of the reforming tube wall, are satisfied. Subsequently, a com;1;putational fluid dynamic (CFD) model of the reformer developed in Tran et al. (2017b) is used to represent the on-line unit at the SMR-based hydrogen facility and is used to characterize the previously unstudied dynamic behavior of the reformer, based on which we develop an optimal strategy to implement the optimized total fuel flow rate to maximize the reformer throughput. Finally, a case study in which the balancing procedure is implemented on the reformer initially operated under the nominal reformer input is proposed, and the results are used to demonstrate that the furnace-balancing scheme successfully determines the optimized reformer fuel input to increase the reformer throughput while meeting the OTWT limits.

      PubDate: 2018-05-02T05:36:49Z
      DOI: 10.1016/j.cherd.2018.03.032
      Issue No: Vol. 134 (2018)
  • Development of a biogas production and purification process using promoted
           gas hydrate formation — A feasibility study
    • Authors: Florian Filarsky; Carsten Schmuck; Heyko Juergen Schultz
      Pages: 257 - 267
      Abstract: Publication date: June 2018
      Source:Chemical Engineering Research and Design, Volume 134
      Author(s): Florian Filarsky, Carsten Schmuck, Heyko Juergen Schultz
      This work proves the feasibility of an integrated process chain, which combines a continuous biogas production unit and a pioneering gas hydrate separation technique to advance biogas utilization. First, a fermentation was launched and optimized to produce biogas. Therefore, a mixed microbiological culture from sewage sludge of a nearby waste water clarification plant was cultivated by feeding a nutrient solution based on saccharose. The second experimental series had the intention to find an optimal hydrate promoter system with a maximized separation factor. To guarantee moderate operating conditions and fast hydrate formation, thermodynamic and kinetic promoters were combined. Tetrahydrofuran was used as thermodynamic, sodium dodecyl sulfate as kinetic promoter. To effectuate higher separation factors, additional substances were tested. One approach deals with additional surfactants of varying HLB numbers. The alternative attempt takes advantage of the properties of physical absorbents. To find an optimal promoter and separation medium several systems were tested. Both experimental series were recombined in a continuous biogas production and upgrading process and separation efficiency was determined to show proof of concept. In a closing experimental series an adapted McCabe–Thiele-diagram was constructed to determine the necessary stage number with the aim to reach a purity within industrial specifications.
      Graphical abstract image

      PubDate: 2018-05-02T05:36:49Z
      DOI: 10.1016/j.cherd.2018.04.009
      Issue No: Vol. 134 (2018)
  • Prediction of filtrate suspended solids and solids capture based on
           operating parameters for belt filter press
    • Authors: B. Kholisa; V.G. Fester; R. Haldenwang
      Pages: 268 - 276
      Abstract: Publication date: June 2018
      Source:Chemical Engineering Research and Design, Volume 134
      Author(s): B. Kholisa, V.G. Fester, R. Haldenwang
      The control and optimization of belt filter presses in the wastewater treatment industry is still largely dependent on operator intervention. This is mainly due to the lack of predictive models for belt filter press performance. This paper presents correlations determined via a factorial trial for the determination of filtrate suspended solids and solids capture as a function of individual process parameters as well as their interactions. A Box–Behnken experimental based design methodology was used to examine the relationship between the operating parameters and the response variables. The process parameters investigated were polymer concentration, polymer dosing, sludge flow rate and the belt speed. The measured responses were the filtrate suspended solids and sludge cake solids. The measured responses obeyed a second order polynomial relationship and their respective interaction effects of the operating parameters were illustrated on three-dimensional surface graphs. The sludge cake solids concentration was found to be constant over the wide range of experimental conditions. The interaction between the sludge flow rate and polymer dosing rate was the second most influential operating parameter on the filtrate suspended solids following sludge flow rate. The belt speed had an insignificant influence on the filtrate suspended solids and solids capture. The correlation is useful to determine the optimum amount of polymer required if the sludge flow rate changes due to production requirements for constant feed solids concentrations and can be used to develop automated control systems for a particular WWTP.
      Graphical abstract image

      PubDate: 2018-05-02T05:36:49Z
      DOI: 10.1016/j.cherd.2018.04.005
      Issue No: Vol. 134 (2018)
  • Prediction of heat transfer, pressure drop and entropy generation in shell
           and helically coiled finned tube heat exchangers
    • Authors: Mohammad Sepehr; Seyed Saeed Hashemi; Mohammad Rahjoo; Vahid Farhangmehr; Ashkan Alimoradi
      Pages: 277 - 291
      Abstract: Publication date: June 2018
      Source:Chemical Engineering Research and Design, Volume 134
      Author(s): Mohammad Sepehr, Seyed Saeed Hashemi, Mohammad Rahjoo, Vahid Farhangmehr, Ashkan Alimoradi
      In this study, the heat transfer, pressure drop and entropy generation in shell and helically coiled tube heat exchangers, are numerically investigated. The heat transfer rate is intensified by installing the annular fins on the outer surface of the coiled tube. The fluid of coil side is the hot water which flows through the coiled tube at temperature of 70°C and velocity of 1m/s. While, on the shell side, the cooling dry air flows through the shell side at temperature of 10°C and velocity of 1–4m/s. The height and number of the fins change, as well as the velocity of the shell side fluid. The main results of this study are some correlations which are suggested for the estimation of the Nusselt number and friction factor of the shell side. Furthermore, the relationship between the NTU, the entropy generation rate and the thermal effectiveness are obtained. The model is validated by comparing the numerical values of the Nusselt numbers of both side and the friction factor of the coil side, with the predicted values based on the previous empirical correlations. In the last section of this study; as a guide for the designer of these types of heat exchangers; a sample problem is defined and solved.
      Graphical abstract image

      PubDate: 2018-05-02T05:36:49Z
      DOI: 10.1016/j.cherd.2018.04.010
      Issue No: Vol. 134 (2018)
  • Inner-phase and inter-phase analysis based operating performance
           assessment and nonoptimal cause identification for multiphase batch
    • Authors: Yan Liu; Ruicheng Ma; Fuli Wang; Yuqing Chang; Furong Gao
      Pages: 292 - 308
      Abstract: Publication date: June 2018
      Source:Chemical Engineering Research and Design, Volume 134
      Author(s): Yan Liu, Ruicheng Ma, Fuli Wang, Yuqing Chang, Furong Gao
      Batch processes play a significant role in modern industrial processes. Nevertheless, the process operating performance may degrade from optimal level, which cancels the economic profits of the plant, and effective techniques for operating performance assessment are essential. Although multimodel approaches are proposed to fit its multiphase characteristic, the effect of combined action of multiple phases on the operating performance of the overall batch, which is very important for operating performance assessment, is neglected. In this study, a novel inner-phase and inter-phase analysis based operating performance assessment and nonoptimal cause identification strategy is proposed to overcome it. The key characteristic of the proposed method is that the inter-phase assessment models are developed based on the inner-phase assessment models of each phase, which takes the correlations and interactions between phases into consideration and reveals the combined effect of multiple phases on the operating performance of the overall batch. Furthermore, online local and global assessments are performed to master the operating performance from different perspectives and improve the algorithm performance. Possible cause variables can be determined by variable contributions under nonoptimal level. The effectiveness of the proposed methodology is demonstrated through a fed-batch penicillin fermentation process and a injection molding process.
      Graphical abstract image

      PubDate: 2018-05-02T05:36:49Z
      DOI: 10.1016/j.cherd.2018.04.013
      Issue No: Vol. 134 (2018)
  • Acting on hydrodynamics to improve the local bed-to-wall heat transfer in
           bubbling fluidized beds
    • Authors: Gerhard Hofer; Gerhard Schöny; Tobias Pröll
      Pages: 309 - 318
      Abstract: Publication date: June 2018
      Source:Chemical Engineering Research and Design, Volume 134
      Author(s): Gerhard Hofer, Gerhard Schöny, Tobias Pröll
      Literature offers several excellent contributions in view of hydrodynamics and heat transfer characteristics of fluidized beds. Our investigations deal with the achievable wall-to-bed heat transfer rates at a tube bundle heat exchanger immersed in a bubbling bed of Geldart Type B particles. We confirm the findings of other authors, who described the lateral distribution of bed voidage as well as horizontal and vertical particle velocity and heat transfer. The heat transfer coefficients in the core of the bed are significantly higher than they are at the walls. An adapted gas distributor with a non-uniform nozzle-grid was used to overcome the disadvantage of unevenly distributed heat transfer. While the heat transfer coefficients close to the wall are 25–50% lower than in the core region when a uniform nozzle-grid is used, the effect can be fully balanced with the modified gas distributor. We conclude that a more even lateral distribution of heat transfer rates is possible while the overall heat exchange rate remains unchanged. Nevertheless, an increased uniformity in lateral particle mixing may indicate an improvement in heat surface load and mass transfer.
      Graphical abstract image

      PubDate: 2018-05-02T05:36:49Z
      DOI: 10.1016/j.cherd.2018.04.015
      Issue No: Vol. 134 (2018)
  • Development of a mathematical model for the anaerobic digestion of
           antibiotic-contaminated wastewater
    • Authors: Rafael Frederico Fonseca; Guilherme Henrique Duarte de Oliveira; Marcelo Zaiat
      Pages: 319 - 335
      Abstract: Publication date: June 2018
      Source:Chemical Engineering Research and Design, Volume 134
      Author(s): Rafael Frederico Fonseca, Guilherme Henrique Duarte de Oliveira, Marcelo Zaiat
      Anaerobic digestion has been investigated as a potential method for treating antibiotic-contaminated livestock wastewaters. Antibiotic removal is mainly associated with biodegradation and sludge adsorption. In environmental concentrations, i.e., from ngL−1 to a few hundred μgL−1, cometabolism is the most likely biodegradation pathway. The overall performance of anaerobic processes may be affected by the hydraulic retention time, and these processes are strongly related to the physical characteristics of the reactor and variations in influent chemical composition. The effects of these factors can be better understood using a mathematical model. Therefore, this paper aimed to develop a model to describe an anaerobic process to treat sulfamethazine (SMZ), which was divided into two stages of microorganism growth and substrate consumption. In addition, three hypotheses regarding sulfamethazine degradation, including substrate cometabolism related to both stages and an apparent enzymatic reaction, were evaluated. A long-term kinetics structure was added to the model to simulate the process of adaptation to each new operational condition. The results showed that sudden increases in chemical oxygen demand (COD) and hydraulic retention time (HRT) had the most significant negative impact on process performance. In addition, a sudden variation of 8μg of SMZ had a similar impact on the process as did 1000mg of filtered COD. Of the degradation hypotheses, the hypothesis related to organic acid consumption was more accurate than that related to hydrolysis; however, neither could account for the response to variations in HRT. The enzymatic approach resulted in a considerably more accurate representation of the influent flow rate variations than did the cometabolic hypotheses.
      Graphical abstract image

      PubDate: 2018-05-02T05:36:49Z
      DOI: 10.1016/j.cherd.2018.04.014
      Issue No: Vol. 134 (2018)
  • Role of cerium in improving NO reduction with NH3 over Mn–Ce/ASC
           catalyst in low-temperature flue gas
    • Authors: Shan Ren; Jie Yang; Tianshi Zhang; Lijun Jiang; Hongming Long; Fuqiang Guo; Ming Kong
      Pages: 1 - 10
      Abstract: Publication date: May 2018
      Source:Chemical Engineering Research and Design, Volume 133
      Author(s): Shan Ren, Jie Yang, Tianshi Zhang, Lijun Jiang, Hongming Long, Fuqiang Guo, Ming Kong
      Mn–Ce mixed oxide was loaded onto activated semi-coke (ASC) via impregnation method and the low temperature selective catalytic reduction (SCR) of NO with NH3 was investigated. The NO conversion and NO oxidation rates were both influenced by the ratios of Ce/(Mn+Ce), and Mn–Ce(0.3)/ASC with loading 5% (mass ratio) Mn–Ce oxides performed the highest catalytic conversion rate of 96.6% and NO oxidation rate of 18.4% at 250°C and GHSV=6000h−1. The changes of physical properties, microstructure, functional groups, crystal structure, surface atomic state, redox property and acid strength for the catalysts were characterized by BET, SEM, FT-IR, XRD, XPS, H2-TPR and NH3-TPD. The results showed that surface functional groups were increased after nitric acid treatment and abundant oxygen groups were observed on semi-coke surface, which were considered to be beneficial for the gas adsorption. Ce doping could raise the Mn4+/Mn x+ rate which played a vital role in catalytic reaction, enhancing the amount of weak and strong acid sites, increasing oxygen vacancies and accelerating the molecular oxygen turning into reactive oxygen species, which could enhance the NO oxidation activity thus contributed to the denitration efficiency.
      Graphical abstract image

      PubDate: 2018-04-16T05:12:41Z
      DOI: 10.1016/j.cherd.2018.02.041
      Issue No: Vol. 133 (2018)
  • A support assisted by photocatalytic Fe3O4/ZnO nanocomposite for thin-film
           forward osmosis membrane
    • Authors: Rezvaneh Ramezani Darabi; Mohsen Jahanshahi; Majid Peyravi
      Pages: 11 - 25
      Abstract: Publication date: May 2018
      Source:Chemical Engineering Research and Design, Volume 133
      Author(s): Rezvaneh Ramezani Darabi, Mohsen Jahanshahi, Majid Peyravi
      Novel thin-film nanocomposite (TFN) membranes were fabricated by incorporation of Magnetite/Zinc oxide (Fe3O4/ZnO) nanocomposite for the forward osmosis (FO) processes. Different concentrations of Fe3O4/ZnO nanocomposite (0.1, 0.2 and 0.3wt%) were added to the sublayer and also 0.02wt% of Fe3O4/ZnO nanocomposite was added to the active layer. The prepared TFN membranes were characterized with aspects to membranes surface and structure properties, separation properties and also FO membrane performance and subsequently compared with thin-film composite (TFC) membrane. The hydrophilicity of TFN membranes surface was improved with increasing Fe3O4/ZnO in the casting and aqueous solution due to the activation of Fe3O4/ZnO nanocomposite under UV light irradiation. Compared to the TFC membrane, the TFN FO membrane water flux was reported to increase remarkably from 16.5 to 29.3L/m2 h (10mM NaCl as feed water (FW)) and 14.5 to 27.2L/m2 h (Acarbose solution as FW) when 2M NaCl salt was utilized as draw solution (DS). The improvement in FO water flux was ascribed to the lower S parameter of modified PES sublayer and the decline of internal concentration polarization (ICP). Long-term experiments demonstrated that the modified FO membranes had lower flux reduction compared to control TFC FO membrane.
      Graphical abstract image

      PubDate: 2018-04-16T05:12:41Z
      DOI: 10.1016/j.cherd.2018.02.029
      Issue No: Vol. 133 (2018)
  • Performance of agitated-vessel U tube heat exchanger using spiky twisted
           tapes and water based metallic nanofluids
    • Authors: M. Khoshvaght-Aliabadi; S. Davoudi; M.H. Dibaei
      Pages: 26 - 39
      Abstract: Publication date: May 2018
      Source:Chemical Engineering Research and Design, Volume 133
      Author(s): M. Khoshvaght-Aliabadi, S. Davoudi, M.H. Dibaei
      An experimental study is performed to investigate hydrothermal characteristics of agitated-vessel U tube heat exchanger. In order to augment the rate of heat transfer in the tube side, two passive enhancement techniques, namely spiky twisted tapes and water based metallic nanofluids, are used. Three twist ratios (α =0.33, 0.67, and 1) with different values of width/depth for peripheral cuts (β =0.33, 0.5, 0.67, 1, 1.5, 2, and 3) and three metallic nanofluids (Cu/water, Fe/water, and Ag/water) are tested. The experiments are done in turbulent flow regime for Reynolds numbers ranging from 7000 to 18,000. The Reynolds number is determined based on hydraulic dimeter of considered geometries as well as inlet flow rate and physical properties of applied working fluid. The results show that spiky twisted tapes and metallic nanofluids both realize great heat transfer enhancement in the agitated-vessel U tube heat exchanger. Utilization of spiky twisted tapes leads to an increase in the range of 11%–67% for the heat transfer coefficient compared with the smooth case. The considered performance factor displays that the most efficient configuration is the spiky twisted tape with α = β =0.33. Also, it is found that the heat transfer enhancement of Ag/water nanofluid is more intensive than Cu/water and Fe/water nanofluids; a maximum enhancement by 18.2% is identified compared with base fluid, while the maximum rise in the pressure drop is only 8.5%.
      Graphical abstract image

      PubDate: 2018-04-16T05:12:41Z
      DOI: 10.1016/j.cherd.2018.02.030
      Issue No: Vol. 133 (2018)
  • Simulated exergy and energy performance comparison of physical–chemical
           and chemical solvents in a sour gas treatment plant
    • Authors: Tahereh Nejat; Azam Movasati; David A. Wood; Hassan Ghanbarabadi
      Pages: 40 - 54
      Abstract: Publication date: May 2018
      Source:Chemical Engineering Research and Design, Volume 133
      Author(s): Tahereh Nejat, Azam Movasati, David A. Wood, Hassan Ghanbarabadi
      A feasibility simulation study evaluates the utilization of the physical–chemical solvent Sulfolane plus Methyl di-ethanol amine (MDEA) plus H2O (Sulfinol-M), to replace the aqueous amine solvent (MDEA) currently used in the sour-gas treatment unit of the large-scale Khangiran gas processing plant (Iran). Physical–chemical solvents, such as Sulfinol-M, have the advantages over chemical solvents in that: (1) their absorption of pollutants is not limited by their stoichiometry; (2) they can be easily regenerated by reduction of pressure alone; and, (3) they demonstrate a strong capability to remove sulphur compounds. The simulation and exergy analysis of this gas treatment plant compare the performance of the currently used MDEA solvent with the Sulfinol-M solvent in various concentrations. The influences of different parameters, including inlet solvent temperature, composition and flow rate of solvents on the removal of H2S and CO2, together with associated exergy and energy losses are evaluated for the MDEA solvent and a range of concentrations of the Sulfinol-M solvent. The simulated exergy analysis demonstrates suitable absorption of acid gases by the Sulfinol-M solvent for less energy and cost than the MDEA solvent.

      PubDate: 2018-04-16T05:12:41Z
      DOI: 10.1016/j.cherd.2018.02.040
      Issue No: Vol. 133 (2018)
  • Gas–liquid mixing in dual agitated vessels in the heterogeneous
    • Authors: Amna Jamshed; Michael Cooke; Zhen Ren; Thomas L. Rodgers
      Pages: 55 - 69
      Abstract: Publication date: May 2018
      Source:Chemical Engineering Research and Design, Volume 133
      Author(s): Amna Jamshed, Michael Cooke, Zhen Ren, Thomas L. Rodgers
      Gas–liquid multi-phase processes are widely used for reactions such as oxidation and hydrogenation. There is a trend for such processes to increase the productivity of the reactions, one method of which is to increase the gas flow rate into the vessel. This means that it is important to understand how these reactors perform as high gas flow rates occurs well into the heterogeneous regime. This paper investigates the mixing performance for the dual axial radial agitated vessel of 0.61m in diameter. 6 blade disk turbine (Rushton turbine) below a 6 Mixed flow Up-pumping and down-pumping have been studied at very high superficial gas velocities to understand the flow regimes operating at industrial conditions. Electrical resistance tomography have been used to produce the 3D images using Matlab, along with analysing the mixing parameters such as Power characteristics, gas hold-up and dynamic gas disengagement. Minimal difference between the two configurations have been reported in terms of gas hold-up, however with the choice of upward and downward pumping impeller power characteristics show significant difference at very high gas flow rates. Also at these high superficial gas velocities, this report introduces a 3rd bubble class, as seen in dynamic gas disengagement experiments, which corresponds to very large slugs of gas.

      PubDate: 2018-04-16T05:12:41Z
      DOI: 10.1016/j.cherd.2018.02.034
      Issue No: Vol. 133 (2018)
  • Simultaneous synthesis of a multiple-effect evaporation system with
           background process
    • Authors: Yinghua Jiang; Lixia Kang; Yongzhong Liu
      Pages: 79 - 89
      Abstract: Publication date: May 2018
      Source:Chemical Engineering Research and Design, Volume 133
      Author(s): Yinghua Jiang, Lixia Kang, Yongzhong Liu
      Multiple-effect evaporation (MEE) is one of the energy-intensive processes. To reduce the energy consumption of this process, it is effective to integrate the MEE with its background process as a whole system. In this paper, a stage-wise superstructure model is proposed, which takes all possibilities in integration of the MEE coupled with its background process into consideration. The corresponding mathematical programming model, featuring a mixed-integer nonlinear programming formulation is then presented to minimize the total energy consumption (TEC) and the total annual cost (TAC) of the system. The optimal topology and operating parameters of the whole system are determined simultaneously by solving the proposed model. The application and effectiveness of the proposed model are illustrated through a case study of a concentrating sugar juice production process. The results obtained by the proposed method agree well with those obtained by the analytical methodology in literature when the energy demand is targeted. To further clarify the advantages of the proposed method, the coupled system with the lowest TAC is also analyzed and discussed, in which the stream matches and operating parameters are determined accordingly.
      Graphical abstract image

      PubDate: 2018-04-16T05:12:41Z
      DOI: 10.1016/j.cherd.2018.02.037
      Issue No: Vol. 133 (2018)
  • CO2 gas–liquid mass transfer and kLa estimation: Numerical investigation
           in the context of airlift photobioreactor scale-up
    • Authors: Mbalo Ndiaye; Emilie Gadoin; Caroline Gentric
      Pages: 90 - 102
      Abstract: Publication date: May 2018
      Source:Chemical Engineering Research and Design, Volume 133
      Author(s): Mbalo Ndiaye, Emilie Gadoin, Caroline Gentric
      This paper deals with gas–liquid mass transfer in an airlift via CFD simulations in the context of photobioreactor (PBR) scale-up. Two aspects are emphasized. Firstly, since carbon uptake by microalgae is of crucial importance as part of PBRs, CO2 transfer is in focus, and numerical simulations are developed to take into account CO2 gas–liquid transfer and dissociation in the aqueous phase. Secondly, since estimating k L a is of crucial importance when scaling-up PBRs, different ways to evaluate k L a are discussed using numerical experiments. Firstly, k L a may be estimated as the volume average value of the local mass transfer coefficients calculated from steady-state hydrodynamics and Higbie penetration model. Secondly, k L a can be deduced from classical dynamic gassing-out/gassing-in experiments. This second method is simulated for O2, as commonly performed experimentally, and also with CO2 since it is the transferred species in PBRs. Results show that k L a field is strongly heterogeneous, as expected in airlifts where gas is mainly present in the riser. Performed with O2, the gassing-in method leads to quite accurate estimation of the spatial average value of local k L a. But, gassing-in methods performed with O2 and CO2 lead to discordant results. In fact, CFD shows that the CO2 depletion in the gas phase has to be accounted for to predict k L a from CO2 gassing-in method, especially at large scale. This study also puts into evidence the potentialities of CFD which allows to get detailed image of local gas–liquid mass transfer, depending on two-phase hydrodynamics, gas phase distribution and transferred species solubility.

      PubDate: 2018-04-16T05:12:41Z
      DOI: 10.1016/j.cherd.2018.03.001
      Issue No: Vol. 133 (2018)
  • Footprint of droplets after impact onto paper surfaces with a hydrophobic
    • Authors: J.O. Marston; M. Moradiafrapoli; C. Li; T. Lam; M.E. Razu; J. Kim
      Pages: 103 - 110
      Abstract: Publication date: May 2018
      Source:Chemical Engineering Research and Design, Volume 133
      Author(s): J.O. Marston, M. Moradiafrapoli, C. Li, T. Lam, M.E. Razu, J. Kim
      This paper presents findings from a study of the impact of liquid droplets onto papers which have been treated to incorporate a hydrophobic barrier. Such papers are currently being explored as new paper-based microfluidic technology for chemical, biological and medical applications, where discrete volumes of liquid (i.e. droplets) are deposited on the paper. We experimentally capture the impingement stage with the aid of high-speed videography and analyze the spreading, retraction and final footprint of the droplets. Understanding the maximum spread and final footprint is important for paper-based devices because it can determine whether or not a droplet that impinges upon them will reach the hydrophilic wicking matrix. We conclude that the final contact area (footprint) could be tuned simply by varying the impact energy of the droplet and vapor deposition time. In contrast to untreated papers, droplets impinging on treated papers impregnate the porous structure but there is no subsequent wicking, i.e. the contact line always pins, which is explained by the interaction of the droplet with fibers of the paper.

      PubDate: 2018-04-16T05:12:41Z
      DOI: 10.1016/j.cherd.2018.03.007
      Issue No: Vol. 133 (2018)
  • Modelling of transport mechanisms and drying shrinkage for multilayer
           ceramic membrane structure
    • Authors: Zawati Harun; Tze Ching Ong; Takeshi Matsuura; Siti Khadijah Hubadillah; Mohd Hafiz Dzarfan Othman; Ahmad Fauzi Ismail
      Pages: 111 - 125
      Abstract: Publication date: May 2018
      Source:Chemical Engineering Research and Design, Volume 133
      Author(s): Zawati Harun, Tze Ching Ong, Takeshi Matsuura, Siti Khadijah Hubadillah, Mohd Hafiz Dzarfan Othman, Ahmad Fauzi Ismail
      In ceramic membrane preparation, the understanding of drying phenomena is very important to ensure no defects and failures that may present in the membrane layers. The combination of hygroscopic and non-hygroscopic multilayer systems that possess different properties is always associated with the failure of the consolidated structure of ceramics during the drying and sintering process. Hence, a two-dimensional mathematical model that coupled mass, heat, and gas transfer was employed to describe the drying process as a whole multilayer ceramic membranes structure. The finite element method was used to solve the model and computation was carried out using a Skyline solver to capture the highly nonlinear and transient process. This study emphasises on the evolution of transport variables during the drying that can be correlated to shrinkage mechanism. The side surface heating boundary was performed with a conclusion that hygroscopic materials have low drying rate due to the material characteristic which inherent higher water retention in a solid matrix. This characteristic also causes higher pore water pressure and gas pressure. The drying of hygroscopic layer has resulted in higher moisture gap which in turn increased the possibilities of cracking. The results obtained from this study enable the optimisation with respect to drying time and material selection thus significantly contributes to the energy saving as well as reducing the environmental effect via less waste energy loss.
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      PubDate: 2018-04-16T05:12:41Z
      DOI: 10.1016/j.cherd.2018.02.039
      Issue No: Vol. 133 (2018)
  • Optimization of extraction conditions using central composite design for
    • Authors: Faegheh Vafaei; Rezvan Torkaman; Mohammad Ali Moosavian; Parisa Zaheri
      Pages: 126 - 136
      Abstract: Publication date: May 2018
      Source:Chemical Engineering Research and Design, Volume 133
      Author(s): Faegheh Vafaei, Rezvan Torkaman, Mohammad Ali Moosavian, Parisa Zaheri
      The extraction conditions for the removal of cobalt(II) from chloride aqueous solution were studied by using supported liquid membrane. The effects of four factors such as the acidity of feed solution (pH), Cyanex301 concentration, cobalt ion concentration in the feed phase as well as sulfuric acid concentration in the stripping phase were investigated by using central composite design which is a subcategory of response surface methodology. The optimum conditions obtained for pH, Cyanex301 concentration, initial cobalt concentration in feed solution, and sulfuric acid concentration were 6, 1mol/L, 98.86mg/L and 1.26mol/L, respectively. The percentage of cobalt extraction equal to 48.21% obtained from the predicted model was in agreement with the experimental data (45.84%), after 3.5h in the experimental conditions. In addition, the other factors such as the types of solvent as a diluent, stripping solution, and the types of extractants and mixtures were studied at the optimum point. The results showed that the percentage of cobalt extraction achieved was 46.85% within 3.5h, in the extraction conditions (Cyanex301 as an extractant, kerosene or chloroform as a diluent and the mixture of sulfuric acid and nitric acid as the stripping phase).
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      PubDate: 2018-04-16T05:12:41Z
      DOI: 10.1016/j.cherd.2018.03.010
      Issue No: Vol. 133 (2018)
  • Modified approach of total site integration for energy conservation: A
           case study of sponge iron cluster
    • Authors: Venkata Ramanaiah; Shabina Khanam
      Pages: 142 - 154
      Abstract: Publication date: May 2018
      Source:Chemical Engineering Research and Design, Volume 133
      Author(s): Venkata Ramanaiah, Shabina Khanam
      In the present work, a modified approach to conserve energy in total site of plants of similar type is developed where conventional methods are not applicable. The approach includes iterative method, if utility and process streams are same, as well as non-iterative method, if these are different. Further, if coal is treated as utility and process streams, a revised model to compute its consumption is also proposed. To illustrate the new approach a cluster of three sponge iron plants are considered where two different strategies are proposed. Results show that reduction in coal consumption, predicted for Strategy-1, is higher than that of Strategy-2. Strategy-1 recovers 99.8% of waste heat available in the modified total site. Thus, through Strategy-1 total amount of energy wasted in the cluster is reduced from 43% to 7.6%. Along with this, Strategy-1 reduces waste gas emissions significantly while making sponge iron cluster more environment friendly. Moreover, 97.9% reduction of water in total site is also observed using Strategy-1, which is an added advantage. Results are compared well with that of the published literature. Further, this approach can be applicable effectively in the site of similar plants irrespective of the operating condition.
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      PubDate: 2018-04-16T05:12:41Z
      DOI: 10.1016/j.cherd.2018.03.014
      Issue No: Vol. 133 (2018)
  • Experimental and numerical investigation on the blade angle of axial-flow
           swirling generator and drainage structure for supersonic separators with
           diversion cone
    • Authors: Yingguang Wang; Dapeng Hu
      Pages: 155 - 167
      Abstract: Publication date: May 2018
      Source:Chemical Engineering Research and Design, Volume 133
      Author(s): Yingguang Wang, Dapeng Hu
      The effect of axial-flow swirling generator and drainage structure with diversion cone on separation performance is very important to supersonic separators. But there is in the absence of experimental studies on separation characteristics of above-mentioned structure. In this paper, both experimental and numerical methods are utilized to investigate the influences of swirling generator and drainage structure. Good agreements are achieved between experimental data and high-order numerical simulation. The results demonstrate that the rotation strength decreases as the outlet angle of the swirler increases. The rotational flow causes the inconsistency of the radial distribution of the fluid in the nozzle and the inconsistency is more noticeable with the increase of rotation intensity. So the blade angle of swirling generator should be determined to find the balance between the expansion characteristic and swirling flow. Comparing two types of drainage structures, the internal extension structure has seriously damaged the supersonic flow in the nozzle, while the flush type drainage port has less influence on fluid. And the smaller outlet angle of drainage port can reduce the effect of drainage port on supersonic flow. When the pressure ratio is 1.4 for the flush type drainage structure, the optimal structural parameter is that the outlet angle of swirler is 55° and the inclination of the drainage structure is 22°. Under the optimum conditions, the ethanol removal rate is 57.06%.
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      PubDate: 2018-04-16T05:12:41Z
      DOI: 10.1016/j.cherd.2018.03.008
      Issue No: Vol. 133 (2018)
  • Life cycle assessment of a biomass CHP plant in UK: The Heathrow energy
           centre case
    • Authors: C. Tagliaferri; S. Evangelisti; R. Clift; P. Lettieri
      Pages: 210 - 221
      Abstract: Publication date: May 2018
      Source:Chemical Engineering Research and Design, Volume 133
      Author(s): C. Tagliaferri, S. Evangelisti, R. Clift, P. Lettieri
      Bioenergy has an important role to play in helping the UK meet its carbon target in 2050 and the European Renewable Energy Directive objectives for 2030. There are however uncertainties associated with the use of bioenergy, and whether or how much it contributes to green-house gas emission reductions. In order to help identifying environmental benefits and burdens associated with biomass use for energy production, an attributional life cycle assessment has been carried out of a biomass-fired CHP plant: the Heathrow Airport energy centre. This facility burns woodchips sourced from nearby forests providing 2 MWe of electricity and 8 MWth of thermal energy which delivers heat and cooling to Heathrow Terminal 2 and low temperature hot water to Terminal 5. A hot spot analysis is conducted to identify the process steps with the largest environmental impact, starting from the harvesting of the forest residue to the disposal of the boiler ash. A scenario analysis is performed to compare the impacts of the biomass plant against fossil alternatives and to identify which renewable energy sources, between biomass and MSW, should be prioritised for development and investment. The results show a reduction in GHG emissions from using biomass, with further benefits if the bottom ash is collected and re-used as a soil conditioner for land-farming or forestry. The paper also discusses the treatment of biogenic carbon in the assessment.

      PubDate: 2018-04-16T05:12:41Z
      DOI: 10.1016/j.cherd.2018.03.022
      Issue No: Vol. 133 (2018)
  • Preparation and characterization of MWCNT-TEPA/polyurethane nanocomposite
           membranes for CO2/CH4 separation: Experimental and modeling
    • Authors: Keivan Mohammad Gheimasi; Omid Bakhtiari; Mojtaba Ahmadi
      Pages: 222 - 234
      Abstract: Publication date: May 2018
      Source:Chemical Engineering Research and Design, Volume 133
      Author(s): Keivan Mohammad Gheimasi, Omid Bakhtiari, Mojtaba Ahmadi
      In the current study, multiwall carbon nanotubes (MWCNTs) were functionalized with Tetraethylene Pentamine (TEPA) and added into polyurethane (PU) polymer matrix to prepare PU-MWCNT-TEPA nanocomposite membranes. The prepared membranes were characterized using FT-IR, XRD and SEM analysis. The analysis results showed that MWCNTs were properly functionalized with TEPA and also uniformly dispersed in polymer matrix. The CO2 permeability increased by 99.8% at 10wt.% loading of MWCNTs-TEPA. The nanocomposite membrane’s CO2/CH4 selectivity was also increased by 9.6%. Impacts of operating pressure and temperature on the membranes’ CO2 permeability and CO2/CH4 ideal selectivity were also investigated. Finally, the gaseous penetrants permeabilities through the nanocomposite membranes were predicted using the Maxwell, the KJN, and the modified KJN models by AAREs of 31.4–35.2, 27.8–31.6, and 4.4–5.7%, respectively.
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      PubDate: 2018-04-16T05:12:41Z
      DOI: 10.1016/j.cherd.2018.03.028
      Issue No: Vol. 133 (2018)
  • A comprehensive study on equilibrium and kinetics of morpholine extraction
           from aqueous stream with CA in toluene: Experimental evaluation,
           extraction model and parametric optimization employing desirability
    • Authors: Alka Kumari; B. Karuna; B. Satyavathi
      Pages: 243 - 254
      Abstract: Publication date: May 2018
      Source:Chemical Engineering Research and Design, Volume 133
      Author(s): Alka Kumari, B. Karuna, B. Satyavathi
      The present study explores the equilibrium and kinetics for the reactive extraction of morpholine, an important industrial reagent from its aqueous stream using capric acid, CA (extractant) in toluene (diluent). An equilibrium model that employs the mass action law was also developed to evaluate the optimum apparent equilibrium constants (K E ), stoichiometric ratio (m) and physical constant (S). Equilibrium model was valid in representing the mechanism of morpholine extraction. Moreover, for the first time the study availed the simultaneous optimization of two significant response characteristics; extraction efficiency ( % E ) and loading ratio ( Z ) using Box–Behnken design (33) employing multivariate desirability function. The statistical models predicted %E of 80.2 and Z of 0.64 for the optimum combination of process parameters as follows: CMO =5%, CCAO =5% and T=303.15K with the desirability of 0.947. Further, the intrinsic kinetics of the extraction model demonstrated that the reactions between morpholine and CA fall in regime 3 (fast chemical reaction in diffusion film), follows first order kinetics with respect to morpholine and displays exothermicity of the process as revealed from thermodynamic studies. The equilibrium and kinetic data is useful for the development, design and reliable scale-up of the extraction process.
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      PubDate: 2018-04-16T05:12:41Z
      DOI: 10.1016/j.cherd.2018.03.027
      Issue No: Vol. 133 (2018)
  • Laminar convection heat transfer and flow performance of Al2O3–water
           nanofluids in a multichannel-flat aluminum tube
    • Authors: Wenwen Guo; Guoneng Li; Youqu Zheng; Cong Dong
      Pages: 255 - 263
      Abstract: Publication date: May 2018
      Source:Chemical Engineering Research and Design, Volume 133
      Author(s): Wenwen Guo, Guoneng Li, Youqu Zheng, Cong Dong
      The heat transfer experiments of Al2O3–water nanofluids were carried out at fixed Reynold number and velocity in a multichannel-flat aluminum tube. The studies we have performed revealed that the convection heat transfer coefficient increased about 5.9% at 0.5vol.% Al2O3 concentration at Re=1732. While at a constant velocity, higher addition of nanoparticles had no evident influence on the heat transfer performance. Compared with theoretical correlations, the data obtained were accorded with Shah equation (deviation <10%) except for those in the entrance. Then a comparative study of Al2O3–water nanofluids and the base fluid was made on the local heat transfer coefficient. The results indicated a higher heat transfer augmentation (11.1%) in the entrance region for 0.5vol.% Al2O3-DW nanofluid, which seems to have a bearing on the thermal conductivity enhancement and the thermal boundary layer thickness reduction. The friction factor and the pressure drop were also studied and the results revealed that the pressure drop slightly increased with the volume concentration of nanoparticles. For 0.5vol.% Al2O3-DW, the average pressure drop increased about 4.4%.
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      PubDate: 2018-04-16T05:12:41Z
      DOI: 10.1016/j.cherd.2018.03.009
      Issue No: Vol. 133 (2018)
  • Integrating crystallization with experimental model parameter
           determination and modeling into conceptual process design for the
           purification of complex feed mixtures
    • Authors: Martin Lucke; Iraj Koudous; Maximilian Sixt; Maximilian J. Huter; Jochen Strube
      Pages: 264 - 280
      Abstract: Publication date: May 2018
      Source:Chemical Engineering Research and Design, Volume 133
      Author(s): Martin Lucke, Iraj Koudous, Maximilian Sixt, Maximilian J. Huter, Jochen Strube
      In this study, crystallization process simulation combined with experimental model parameter determination at lab-scale is investigated in order to allow the integration of crystallization unit operation into conceptual process design for the purification of complex mixtures and possibly assist in formulation. A one-dimensional population balance model is combined with experiments, which are selected and carried out as a typical example for an industrial fermentation broth (e.g. vanillin), focusing on determination of solubility and growth kinetics as well as kinetics of agglomeration and breakage. Model parameter determination and model validation show that the named effects are adequately described by the model. Hence, model-based process design of purification by crystallization and particle formation enabling integration into formulation considering relevant effects regarding a complex feed mixture becomes possible within a conceptual process design. Further applications are under consideration.

      PubDate: 2018-04-16T05:12:41Z
      DOI: 10.1016/j.cherd.2018.03.029
      Issue No: Vol. 133 (2018)
  • Series versus parallel reboilers in distillation columns
    • Authors: William L. Luyben
      Pages: 294 - 302
      Abstract: Publication date: May 2018
      Source:Chemical Engineering Research and Design, Volume 133
      Author(s): William L. Luyben
      Multiple reboilers are used in distillation columns for several reasons such as implementing heat integration, intermediate reboilers, auxiliary reboilers and vapor recompression. If there is a single source of hot vapor to be used in multiple heat exchangers, the flowsheet can use either a series or a parallel arrangement, depending on the temperature levels of the heat sinks. The purpose of this paper is to point out that the series arrangement can present difficult control problems because of interaction between the units. In the parallel configuration, the heat transferred to each sink can be easily divorced from the others. In the series configuration, more complex methods must be used such as bypassing and flooding to adjust heat transfer in individual units. The controllability of the parallel configuration is demonstrated for a lower-partitioned divided-wall reactive distillation column with vapor recompression.

      PubDate: 2018-04-16T05:12:41Z
      DOI: 10.1016/j.cherd.2018.03.025
      Issue No: Vol. 133 (2018)
  • Improved design and optimization for separating tetrahydrofuran–water
           azeotrope through extractive distillation with and without heat
           integration by varying pressure
    • Authors: Jinglian Gu; Xinqiang You; Changyuan Tao; Jun Li; Weifeng Shen; Jie Li
      Pages: 303 - 313
      Abstract: Publication date: May 2018
      Source:Chemical Engineering Research and Design, Volume 133
      Author(s): Jinglian Gu, Xinqiang You, Changyuan Tao, Jun Li, Weifeng Shen, Jie Li
      From the view of thermodynamic insight, a new concept (ROE: FE,Pope/FE,Pref), the ratio of the entrainer flow rate (FE) needed for reaching given relative volatility at operating pressure (Pope) to reference pressure (Pref), is firstly proposed to quantitatively determine the search space of operating pressure of the extractive column in a homogeneous extractive distillation (ED) process for the separation of binary minimum azeotrope with heavy entrainer. This novel concept is illustrated by the extractive distillation of tetrahydrofuran–water minimum boiling point mixture with an entrainer dimethyl sulfoxide. Six process designs under different pressures are obtained by a two-step optimization procedure and compared from the economic view based on total annual cost (TAC). Furthermore, three double-effect heat integration (DEHI) processes, are employed under atmospheric and a reduced pressure for the first time to further improve the energy efficiency and investigate the effect of pressures on the studied ED process. The final results of case study demonstrate the optimal heat integration approach with a suitable low pressure is the most economic one among the three DEHI processes. The TAC of the best proposed design exhibits a 20.3% reduction than that at atmosphere pressure. The proposed pressure selection rule and optimization process are helpful for reducing the TAC of the ED process.
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      PubDate: 2018-04-16T05:12:41Z
      DOI: 10.1016/j.cherd.2018.03.015
      Issue No: Vol. 133 (2018)
  • Experimental study on the solid suspension characteristics of coaxial
    • Authors: Baoqing Liu; Zilong Xu; Fangyi Fan; Bolin Huang
      Pages: 335 - 346
      Abstract: Publication date: May 2018
      Source:Chemical Engineering Research and Design, Volume 133
      Author(s): Baoqing Liu, Zilong Xu, Fangyi Fan, Bolin Huang
      Coaxial mixers as novel mixers have the characteristics of high flexibility and wide adjustability. Three kinds of coaxial mixers consisting of an outer anchor and different inner impellers (six 45° pitched-blade turbine, propeller and Rushton turbine) and single-impeller mixers were investigated and compared in viscous systems. Effects of rotation and pumping modes, outer impeller speed, inner impeller diameter, liquid viscosity, solid volume fraction and particle diameter on the just-suspension impeller speed and power consumption were also studied. Results showed that the coaxial mixers were more energy efficient than the single-impeller mixers, and had greater advantage in systems of higher viscosity and solid volume fraction. Different from single-impeller mixers, adopting up-pumping mode was more energy efficient for coaxial mixers when the anchor speed was relatively high. In addition, the coaxial mixers with the inner up-pumping propeller and six 45° pitched-blade turbine had obvious superiority compared with the combination of anchor and Rushton turbine in terms of power consumption. Based on the experimental data, a new correlation for predicting just-suspension impeller speed of coaxial mixers was proposed.
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      PubDate: 2018-04-16T05:12:41Z
      DOI: 10.1016/j.cherd.2018.03.035
      Issue No: Vol. 133 (2018)
  • Gas–solid fluidization of cohesive powders
    • Authors: Federica Raganati; Riccardo Chirone; Paola Ammendola
      Pages: 347 - 387
      Abstract: Publication date: May 2018
      Source:Chemical Engineering Research and Design, Volume 133
      Author(s): Federica Raganati, Riccardo Chirone, Paola Ammendola
      Fine and ultrafine powders (down to nanoparticles) have recently received growing interest in both industrial and academic sectors due to their very distinctive features, mainly coming from their very small primary particle size and very large surface-to-volume ratio. Indeed, due to these characteristics, they can provide better contact efficiency and higher reaction rates per unit volume of reactor than traditional materials in the case of gas/solid and solid/solid reactions. They have been used to produce a large variety of materials, such as catalysts, sorbents, cosmetics, etc. Therefore, the interest in using this type of granular materials in a variety of industrial processes raises many questions about how they can be handled. Therefore, the interest in using this type of granular materials in a variety of industrial processes raises many questions on how they can be handled and processed (e.g. mixing, transporting and modifying the surface properties) in large-scale applications. With reference to this point, among all the available techniques for continuously handling and dispersing granular solids, gas fluidization is one of the most efficient, mainly due to the large gas–solid contact area. The aim of this work is to provide a critical review of experimental/theoretical research and latest progress in the science and technology of gas fluidization of fine/ultrafine particles, thus deeply covering the current international state-of-the-art. In particular, the challenges linked to the extensive use of these powders have been discussed, highlighting and explaining the fundamental aspects needed to comprehend the complexity of the process and provide possible answers/solutions.
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      PubDate: 2018-04-16T05:12:41Z
      DOI: 10.1016/j.cherd.2018.03.034
      Issue No: Vol. 133 (2018)
  • Synthesis, characterization, and application of
           trihexyl(tetradecyl)phosphonium chloride as promising solvent for
           extractive desulfurization of liquid fuel
    • Authors: Swapnil Dharaskar; Mika Sillanpaa
      Pages: 388 - 397
      Abstract: Publication date: May 2018
      Source:Chemical Engineering Research and Design, Volume 133
      Author(s): Swapnil Dharaskar, Mika Sillanpaa
      Nowadays there are serious regulations to eliminate sulfur from fuels because the SOx created through the combustion of fuel containing sulfur compounds which causes air pollution and have hazardous environmental influence. In present paper experimental data on extractive desulfurization (EDS) of dibenzothiophene (DBT), thiophene, benzothiophene, and other sulfur derivatives from liquid fuel using trihexyl(tetradecyl)phosphonium chloride [THTDP]Cl has been presented. The FTIR, NMR and TG/DSC spectra have been discussed for the molecular confirmation and thermal stability of [THTDP]Cl. Further, conductivity, solubility, and viscosity analysis were carried out. The effects of reaction time, temperature, sulfur compounds, ultra-sonication, recycling and regeneration on DBT removal from fuel were also investigated. In EDS, the DBT removal in n-dodecane was 81.5% for mass ratio of 1:1 in 30min at 30°C under the mild reaction conditions. Also, real fuels desulfurization and multistage extraction was examined. The results of the present work positively offer valuable information on synthesis, and application of phosphonium ionic liquids as promising solvents for EDS.
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      PubDate: 2018-04-16T05:12:41Z
      DOI: 10.1016/j.cherd.2018.03.016
      Issue No: Vol. 133 (2018)
  • Inside Front Cover
    • Abstract: Publication date: May 2018
      Source:Chemical Engineering Research and Design, Volume 133

      PubDate: 2018-05-02T05:36:49Z
  • Fast and green separation of malachite green in water samples by
           micro-dispersion scanometry method without heating, cooling and organic
           solvents at room temperature
    • Authors: Shahram Nekouei; Farzin Nekouei; Mohammad Ali Ferdosi Zadeh
      Abstract: Publication date: Available online 11 April 2018
      Source:Chemical Engineering Research and Design
      Author(s): Shahram Nekouei, Farzin Nekouei, Mohammad Ali Ferdosi Zadeh
      In the present work, a novel, easy, rapid, green, and, economical technique, micro-dispersion scanometry (MDS) is presented for the first time and employed using suspended Ni(OH)2 nanopowder in the micellar medium for the determination of slight amounts of malachite green chloride. In the meanwhile, we introduced a new simple method for the synthesis of Ni(OH)2 nanopowder followed by characterization via various methods such as scanning electron microscopy (SEM), X-Ray diffraction (XRD) and, Brunauer, Emmett and Teller (BET). The process of scanning (detecting) was done on the cells including the sample solution via a usual flatbed-scanner. Then, for analyzing the color of the cells, a software system designed in Visual Basic (VB 6), to R (red), G (green), and B (blue) values was applied. To build the cells, some holes were created in the plexiglas sheet. The impact of experimental variables namely pH, weight of sorbent, volume of 4% Triton X-114, eluting solution, and sample volume have been investigated and optimized in multivariate method using design Expert 7.0 software for statistical data analysis. A contrast done between the proposed and traditional UV–vis spectrophotometry methods revealed the comparable tendency in both methods Calibration curves were linear in the range of 0.37–110 and 0.45–110μgL−1 for scanometry and UV–vis methods, respectively. The detection limits were 0.060 and 0.068μgL−1 for scanometry and UV–vis methods, respectively. The capacity of Ni(OH)2 nanopowder for malachite green was 80mgg−1.

      PubDate: 2018-04-16T05:12:41Z
      DOI: 10.1016/j.cherd.2018.04.008
  • Demulsifier Assisted Film Thinning and Coalescence in Crude Oil Emulsions
           Under DC Electric Fields
    • Authors: Sameer Mhatre; Sébastien Simon; Johan Sjöblom; Zhenghe Xu
      Abstract: Publication date: Available online 10 April 2018
      Source:Chemical Engineering Research and Design
      Author(s): Sameer Mhatre, Sébastien Simon, Johan Sjöblom, Zhenghe Xu
      Electrocoalescence has been considered a most efficient method of crude oil dewatering; however, just electric fields are not enough when dealing with heavy crude oils. In this work we studied effect of asphaltene flocculation and effectiveness of variety of chemical demulsifiers in electrocoalescence of water-in-crude oil emulsions. A parallel plate electrode cell was used to apply linearly rising uniform DC electric field to a thin layer of emulsion and the current running through the emulsion was monitored as an indicator of progress in the coalescence. In the first part of the study, model crude oils were used to investigate the roles of flocculated asphaltenes and flocculation inhibitor in electrocoalescence process. It was observed that the asphaltene flocculation adversely affects the rate of electrocoalescence. Second part compares effectiveness of different chemical demulsifiers in breaking water-in-crude oil emulsions under electric field. The experimental observations suggest that there exist a threshold demulsifier concentration limit and further increasing the concentration does not improve electrocoalescence rate. Also the addition of a demulsifier before dispersion of water results into faster separation as compared to the electrocoalescence in emulsion where the demulsifier was added later. Further, we devised a model for qualitative prediction of film drainage between two demulsifier-laden water-crude oil interfaces under a constant DC electric field. The film thinning rates predicted by the model are consistent with the experimentally measured critical electric field values.

      PubDate: 2018-04-16T05:12:41Z
      DOI: 10.1016/j.cherd.2018.04.001
  • Dynamic parameter estimation and identifiability analysis for
           heterogeneously-catalyzed reactions: Catalytic synthesis of nopol
    • Authors: Daniel Casas-Orozco; Aída Luz Villa; Omar J. Guerra; Gintaras V. Reklaitis
      Abstract: Publication date: Available online 10 April 2018
      Source:Chemical Engineering Research and Design
      Author(s): Daniel Casas-Orozco, Aída Luz Villa, Omar J. Guerra, Gintaras V. Reklaitis
      In this work, a methodology for the parameter estimation of heterogeneously-catalyzed reactions is presented. A simulation-optimization framework based on a dynamic model was coupled with an identifiability analysis, in order to detect for which parameters the dynamic model is most sensitive. The implemented identifiability analysis was based on rank-revealing matrix factorizations, with singular values as criteria for parameter selection. As the dynamic equation systems describing catalytic reactions are expected to be ill-posed, a subset selection step based on identifiability analysis was included. In order to illustrate the methodology, the ODE system describing the heterogeneously-catalyzed reaction system for the production of nopol from β-pinene and formaldehyde was used as a case study. After applying the methodology, two out of five kinetic parameters were found to be identifiable, consistent with a Langmuir Hinshelwood Hougen Watson (LHHW) mechanism that considers adsorption on catalytic sites of different nature. Confidence intervals of the estimated parameters belonging to the identifiable subset were not higher than 3 % of the parameter value. The results of this work show that the proposed mechanism is capable of reproducing the dynamics of the reaction system, and are an important input for the design of a three-phase reactor for nopol production.
      Graphical abstract image Highlights

      PubDate: 2018-04-16T05:12:41Z
      DOI: 10.1016/j.cherd.2018.04.002
  • Synergism between Ionic Liquid and Ultrasound for Greener Extraction of
           Geraniol: Optimization using Different Statistical Tools, Comparison and
    • Authors: Miral R. Thakker; Jigisha K. Parikh; Meghal A. Desai
      Abstract: Publication date: Available online 10 April 2018
      Source:Chemical Engineering Research and Design
      Author(s): Miral R. Thakker, Jigisha K. Parikh, Meghal A. Desai
      A new-fangled concept of combining synthesized ionic liquid with ultrasound was executed for the isolation of geraniol, a generally recognized as safe (GRAS) terpene. Shortening the extraction time and lowering the solvent requirement along with maintaining the quality of the product were the frugal aspects of this technique. Solubilization study was performed using four different water soluble synthesized ionic liquids. N, N, N, N', N', N' − hexaethyl − propane − 1, 3 − diammonium dibromide was found to be the most suitable solvent amongst the selected ionic liquids. Optimization of process parameters viz., ultrasound power, volume of ionic liquid solution, concentration of ionic liquid and extraction time was carried out with the help of the Taguchi method as well as Box-Behnken response surface design. Box-Behnken response surface design was found to be the superlative optimization technique with 1.73% (w/w) yield of geraniol under optimized conditions (250W ultrasound power, 40mL aqueous solution having 10% ionic liquid and 18min of extraction time). Conventional extraction involving organic solvents was also investigated and compared with the proposed extraction technique. Predictive modelling of the experimental data was also performed using the artificial neural network. The extraction mechanism was explicated by microscopic study to recognize the effect of ionic liquid and ultrasound. The current technique was turned out to be the sustainable extraction technique when compared in terms of yield, solvent consumption and extraction time. Energy efficiency and reduced environmental burden were the rewarding outcome of the study. The proposed technology incorporating ionic liquid and sonication in a single system can be studied in detail for industrial perspective.
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      PubDate: 2018-04-16T05:12:41Z
      DOI: 10.1016/j.cherd.2018.04.003
  • CFD analyses of liquid flow characteristics in a rotor-stator reactor
    • Authors: Yi Ouyang; Siwen Wang; Yang Xiang; Zemeng Zhao; Jiexin Wang; Lei Shao
      Abstract: Publication date: Available online 10 April 2018
      Source:Chemical Engineering Research and Design
      Author(s): Yi Ouyang, Siwen Wang, Yang Xiang, Zemeng Zhao, Jiexin Wang, Lei Shao
      Rotor-stator reactor (RSR) is a novel device for the intensification of multiphase processes and can greatly boost mass transfer and mixing efficiency. However, due to the unique structure, the flow characteristics in the RSR is unknown and difficult to acquire by experiments. Therefore, this work employed computational fluid dynamics (CFD) technique to reveal liquid flow behaviors in an RSR for the first time. The volume of fluid (VOF) multiphase model, sliding model (SM) and standard k-ε model were used to simulate liquid flow field in a typical two-dimensional computational framework of the RSR. It was found that the droplet size and velocity in the cavity zone of the RSR were in agreement with the published data of the visual experiments. The results show that the liquid was quickly split and synchronized with the motion of the rotor layers when injected into the RSR. Two droplet formation schemes were observed in the RSR: “ligament to droplets disintegration” and “droplets disintegration”. The droplets size distribution could be well described by Rosin-Rammler model. The droplets diameter decreased but the droplet velocity increased with increasing rotational speed, while the droplets diameter increased and the droplet velocity changed little with increasing liquid inlet velocity. With the increase of the number of rotor/stator layers, droplet size decreased and velocity increased. The agreement of the experiment and simulation results indicate that the CFD technique is an effective tool to analyze the hydrodynamic characteristics of RSR.
      Graphical abstract image

      PubDate: 2018-04-16T05:12:41Z
      DOI: 10.1016/j.cherd.2018.04.006
  • Modelling the Selective Removal of Sodium Ions from Greenhouse Irrigation
           Water Using Membrane Technology
    • Authors: Z. Qian; H. Miedema; L.C.P.M. de Smet; E.J.R. Sudhȍlter
      Abstract: Publication date: Available online 9 April 2018
      Source:Chemical Engineering Research and Design
      Author(s): Z. Qian, H. Miedema, L.C.P.M. de Smet, E.J.R. Sudhȍlter
      A model is presented for the Na+ and K+ levels in the irrigation water of greenhouses, specifically those for the cultivation of tomato. The model, essentially based on mass balances, not only describes the accumulation of Na+ but includes a membrane unit for the selective removal of Na+ as well. As determined by the membrane properties, some of the K+ is removed as well. Based on real-life process parameters, the model calculates the Na+ and K+ concentration at three reference points. These process parameters include the evapotranspiration rate, the K+ uptake by the plants, the Na+ and K+ content of the fertilizer, the Na+ leaching out from the hydroponic substrate material, and the Na+ and K+ removal efficiency of the membrane unit. Using these parameters and given a constant K+ concentration of the irrigation water entering the greenhouse of 6.6mM (resulting in the optimal K+ concentration for tomato cultivation), the composition of the solution is completely defined at all three reference points per irrigation cycle. Prime aim of this investigation is to explore the requirements for the selective membrane that currently is developed in our lab. It is found that even for a limited Na+ over K+ selectivity of 6, after a number of cycles the Na+ level reaches steady state at a level below the upper (toxic) threshold for tomato cultivation (20mM). Economic aspects and ways of implementation of such a system are briefly discussed.
      Graphical abstract image

      PubDate: 2018-04-16T05:12:41Z
      DOI: 10.1016/j.cherd.2018.03.040
  • Coupled model based on radiation transfer and reaction kinetics of
           gas-liquid-solid photocatalytic mini-fluidized bed
    • Authors: Xiaoyun Wang; Mingyan Liu; Zhongguo Yang
      Abstract: Publication date: Available online 8 April 2018
      Source:Chemical Engineering Research and Design
      Author(s): Xiaoyun Wang, Mingyan Liu, Zhongguo Yang
      Gas-liquid-solid mini-fluidized bed could be a potential high-efficient photocatalytic reactor in wastewater treatment. Such a photocatalytic reactor with bed diameter of 6mm was developed and photocatalytic degradation of methylene blue (MB) was investigated. Mass transfer coefficient of the three-phase mini-fluidized bed was 1.9 and 4.8 times greater than that of liquid-solid mini-fluidized bed and mini-bubble column, respectively. A coupled model based on radiation transfer and reaction kinetics was built. Polychromatic Xe lamp was discretized to obtain the absorbed photons during photocatalytic reaction. The non-uniform radiation field responsible for MB local volumetric degradation rate affected by the scattering and absorption of catalyst particles and micro-bubbles in mini-reactor was solved. Based on mechanism of photocatalytic degradation MB, the reaction kinetics obtained by steady-state hypothesis was coupled into the radiation transfer model. Dispersed mini-bubble flow was obtained by proper operation conditions corresponding to higher apparent quantum efficiency of 0.19% − 0.44% also discussed.
      Graphical abstract image

      PubDate: 2018-04-16T05:12:41Z
      DOI: 10.1016/j.cherd.2018.04.004
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