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Zeitschrift für Hochschulrecht, Hochschulmanagement und Hochschulpolitik: zfhr     Hybrid Journal   (Followers: 3)
Zeitschrift fur Management     Hybrid Journal   (Followers: 1)
Zeitschrift für öffentliches Recht     Hybrid Journal   (Followers: 13)
Zeitschrift für Politikberatung     Hybrid Journal   (Followers: 1)
Zeitschrift für Psychodrama und Soziometrie     Hybrid Journal  
Zeitschrift fur Rheumatologie     Hybrid Journal   (Followers: 2, SJR: 0.15, h-index: 31)
Zeitschrift für Vergleichende Politikwissenschaft     Hybrid Journal   (Followers: 5)
Zoomorphology     Hybrid Journal   (Followers: 2, SJR: 0.417, h-index: 24)
Zorg en Financiering     Hybrid Journal  

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Journal Cover Journal of Material Cycles and Waste Management
   Journal TOC RSS feeds Export to Zotero [4 followers]  Follow    
   Hybrid Journal Hybrid journal (It can contain Open Access articles)
     ISSN (Print) 1611-8227 - ISSN (Online) 1438-4957
     Published by Springer-Verlag Homepage  [2209 journals]   [SJR: 0.327]   [H-I: 13]
  • A new theory of the creation of biomethane from aluminium-containing
           inorganic wastes
    • Abstract: Abstract Energy by-products from the co-combustion of municipal solid waste with coal or biomass are monitored only in terms of oxides; the amount of metallic aluminium is not determined. When these energy by-products are deposited at landfills, the alkali metal compounds in landfill bodies undergo reactions with aluminium in the presence of water. This leads to the formation of hydrogen and its possible bioconversion into methane. The article summarises the findings of the possible development of methane and hydrogen from the ashes of 11 items of typical municipal waste containing aluminium, burned in power plants, which are then landfilled. The assessment of the new information on aluminium-waste reactions in landfill bodies and the metabolism of some bacteria may give rise to a new theory of the formation of the biomethane contained in the landfill gas.
      PubDate: 2014-10-25
       
  • Digestion reactions of paper sludge combustion ash in strong alkaline
           solutions at 60 °C
    • Abstract: Abstract Alkaline reactions of paper sludge combustion ash at low temperature (60 °C) were performed using a calcite-rich paper ash (PA 1) and a gehlenite-rich ash (PA 2). Strong alkaline conditions (8, 12, 16 M NaOH) were revealed at reaction times of 1–4 h and 12–24 h. Reactions were performed with pure ashes and in the presence of NaAlO2. The products were characterized by XRD, FTIR, SEM/EDX, gravimetry and chemical analysis. The conversion was found to proceed mainly in the period between 1 and 4 h. Portlandite and hydrogarnet were observed from PA 1 in 8 M NaOH. Onset of formation of Ca4Al2O6CO 3 . 11H2O beside Ca(OH)2 could be analyzed after reaction of PA 1 in 12 M and 16 M NaOH. Addition of NaAlO2 favored crystallization of hydrogarnet and Ca4Al2O6CO 3 . 11H2O. For PA 2 gehlenite remained stable, but a high portlandite fraction was observed. Addition of NaAlO2 yielded hydrogarnet beside gehlenite in 8 M NaOH. Higher alkalinities favored crystallization of Ca4Al2O6CO 3 . 11H2O and onset of dissolution of gehlenite. Finally transformation of Ca4Al2O6CO 3 . 11H2O into sodium aluminum silicate hydrate was observed. All results were discussed with regard to heavy metal distribution of the initial PA between the alkaline digestion solution and the products. In conclusion suitable applications of the products were proposed.
      PubDate: 2014-10-25
       
  • Mineralogical comparison of coal fly ash with soil for use in agriculture
    • Abstract: Abstract Mineralogical comparison of coal fly ash with soil and other material such as montmorillonite, charcoal was done by X-ray diffraction (XRD), thermo gravimetric analysis (TGA), Fourier-transform infrared spectroscopy (FTIR) and Scanning electron micrograph (SEM) with EDS. Fly ash showed high thermal stability with least weight loss as observed in TGA and SEM graph indicated that flyash is composed of spherical structures with more surface area for interaction; XRD and EDS studies showed that amorphous content of ash consists of calcium oxide, potassium and major crystalline phases observed were quartz (SiO2) and aluminum silicon oxide (Al4.52Si1.48) and haematite (Fe2O3). Charcoal, was amorphous in nature consisting of carbon and graphite. Soil and montmorillonite showed similar results in XRD, FTIR and thermal analysis having porous nature with silica as major constituent. Fly ash was found to be alkaline in nature having pH 7.85 and electrical conductivity 0.14 µS/m, good water holding capacity (62 %) and various macro and micronutrients as compared to other material viz. soil, charcoal, montmorillonite and hence, its mineralogical composition ascertains its applicability as a carrier for different microbial inoculants for soil application in agriculture which can act as an economic source of nutrient supplement for crop plants.
      PubDate: 2014-10-24
       
  • Estimation of gypsum hemihydrate content in recycled gypsums derived from
           gypsum boards
    • Abstract: Abstract In order to utilize reclaimed gypsums (gypsum board waste) derived from waste plasterboards as geo-materials, thermal behaviors of the reclaimed gypsums and reagent gypsum are investigated in this paper. Furthermore, simple density measuring method of judging quality of the reclaimed gypsums is examined to determine the gypsum hemihydrate content. As the results, it was found that the dihydrate gypsum is changed into the hemihydrate gypsum under thermal condition of 90 °C and the hemihydrate gypsum is changed into anhydrite under that of 120 °C with heating of 24 h. The followings were clarified in this paper. The cement density measuring method was available in order to measure the density of reclaimed gypsums; that density depended on the drying conditions of the reclaimed gypsums; and the density measuring method was appropriate to estimate the gypsum hemihydrate content in reclaimed gypsums. Furthermore, it was found that the quality control method based on the density was effective by calculating the gypsum hemihydrate content from the density values of reclaimed gypsums.
      PubDate: 2014-10-24
       
  • Pt/ITQ-6 zeolite as a bifunctional catalyst for hydrocracking of waste
           plastics containing polystyrene
    • Abstract: Abstract Thermal and catalytic hydrocracking of polystyrene to fuels was compared. The use of a bifunctional (platinum and acidic sites) catalyst such as Pt/Ferrierite not only increases conversion but also selectivity to a wider and more interesting variety of products in the gasoline range (C5–C12). As polymer molecules present steric hindrance to access internal active sites in the catalyst, Pt/ITQ-6 was prepared by delamination to maximize the external surface of the catalyst while keeping its composition and type. Although Pt/ITQ-6 presented lower acidity than Pt/Ferrierite, it was mostly external and, thus, accessible to the reactants. In this way, Pt/ITQ-6 significantly improved activity and selectivity of Pt/Ferrierite. The performance of Pt/ITQ-6 when recycled polystyrene was used as reactant proved this catalyst is very promising for this application, although catalytic activity decreased as a consequence of plastic additives and impurities.
      PubDate: 2014-10-21
       
  • Emission of particulate matter 2.5 (PM 2.5 ) and elements from municipal
           solid waste incinerators
    • Abstract: Abstract To determine the concentration and behavior of fine particulate matter (PM2.5) from municipal solid waste incineration, size-classified dust samples were collected from four incineration facilities using cascade impactors. The total dust and PM2.5 concentrations were 1.7–236 and 0–104 μg/Nm3, respectively, in the flue gas sampled from the stacks. The total dust concentration in the flue gas was 1/50 or less of the concentrations measured previously in the same facilities with the operation of an electrostatic precipitator. Each air pollution control device used in the facilities was evaluated from the perspective of PM2.5 removal. A bag filter, activated carbon tower and selective catalytic reduction were all considered to be effective. The removal efficiency of PM2.5 was more than 99.99 %. Analysis of the particle size distributions of the dust identified two peaks around 1 and 10 μm at the inlet of the BF. Based on the results of an elemental analysis of the dust, the particle size distributions of each element were also calculated. As a result, the emission of PM2.5 as primary particles from a state-of-the-art municipal solid waste incinerator was estimated to be very low.
      PubDate: 2014-10-21
       
  • Cotton shell utilization as a source of biomass energy for bio-oil by
           flash pyrolysis on electrically heated fluidized bed reactor
    • Abstract: Abstract Extensive concentration has been given to the development of renewable energy due to imminent demand of fossil fuels and environmental concerns over global warming. Biomass materials are used since millennia for meeting myriad human needs including energy. In this study, the pyrolysis characteristics of cotton shell were investigated to evaluate their potential use as source of bio-oil. Flash pyrolysis of the cotton shell was carried out on an electrically heated fluidized bed reactor. The effects of operating parameters such as temperature, particle size and sweep gas flow rate were investigated. In this study, the maximum yield of pyrolysis bio-oil 51.25 wt% can be obtained under the operation temperature of 450 °C, 1 mm particle size at sweep gas flow rate of 1.75 m3/h. The liquid product was analyzed for physical, elemental and chemical composition using Fourier transform infra-red (FTIR) spectroscopy, gas chromatography (GC) and 1H NMR spectroscopy.
      PubDate: 2014-10-19
       
  • Selection of management option for solid waste from olive oil industry
           using the analytical hierarchy process
    • Abstract: Abstract This paper considers the process of selecting a appropriate olive mill solid waste management option in Jordan. Six alternatives were found to be possible options for olive mill solid waste management. Those alternatives are: animal feed, energy recovery, extraction of useful materials, co-combustion, fertilizers, and disposal without treatment. Prioritization of these six alternatives was performed through the analytical hierarchy process. Management options were prioritized based on three criteria: environmental effects, economical benefits, and the technology involved. Priorities given to each of criteria were evaluated through soliciting experts and olive mills owners opinions. Analytical hierarchy process model results revealed that co-combustion option is most favorable followed by the animal feed alternative and lease favorable is disposal without treatment. Sensitivity of the proposed analytical hierarchy process model was addressed as the priorities may change. Model sensitivity analysis showed that our model decision is robust to moderate changes in priorities. Unless the environmental criteria given a very high priority, co-combustion remains as the most favorable management option.
      PubDate: 2014-10-19
       
  • Use of acid cation-exchange resin for catalytic conversion of soybean acid
           oil to biodiesel
    • Abstract: Abstract Soybean acid oil (SAO), a by-product of soybean oil refining, contains large amounts of free fatty acids (FFAs). In the present work, the esterification of FFAs in SAO with methanol over four strong acid cation-exchange resins to synthesize biodiesel was studied in a batch reactor. The effects of external and internal diffusion, catalyst amount, methanol/FFAs ratio, and temperature in the esterification over the optimal resin (LS-50) were assessed. After 140 min, the esterification reached equilibrium, and high FFAs conversion (91.02 %) was obtained under the optimized conditions. Based on the obtained data, the reaction kinetics was studied, and the kinetics of the optimized FFAs esterification catalyzed by LS-50 fitted well to the pseudo-homogeneous (P–H) kinetic model. LS-50 could be successfully reused for at least 8 cycles, and its deactivation mechanism was also investigated. The fuel property parameters of the synthesized biodiesel conformed to the standards for biodiesel in the US (ASTM D 6751-03).
      PubDate: 2014-10-18
       
  • Biodiesel production from waste shortening oil from instant noodle
           factories
    • Abstract: Abstract Waste shortening oil (WSO) from instant noodle factories was used for biodiesel production by transesterification using alkali as a catalyst in a laboratory scale. The effects of various parameters such as potassium hydroxide concentration, methanol/WSO molar ratio, temperature and reaction time on the biodiesel production were investigated. To determine the optimal operating condition for biodiesel production, potassium hydroxide concentration from 0.25 to 1.5 wt%, methanol/WSO molar ratio from 3:1 to 9:1, temperature from 35 to 65 °C and reaction time from 30 to 90 min were employed. The highest ester yield of biodiesel was obtained at the catalyst concentration of 1.0 wt% KOH, methanol/WSO molar ratio of 8:1, temperature of 55 °C, and reaction time of 60 min. Biodiesel obtained had many advantages such as high cetane number, low acid value and carbon residue and can be used as an alternative diesel without modifications to engine or injection system.
      PubDate: 2014-10-05
       
  • Characterization of lorry washing sludge
    • Abstract: Abstract The sludge generated by washing lorry refuse and some fractions of municipal solid waste have been studied, to justify that washing sludge presents no danger and can therefore be managed adequately in a landfill, as well as other municipal solid waste fractions. One problem attributed to this type of sludge is its high level of sulfide content, which causes this waste to be considered hazardous. The determination of sulfide content in the studied samples was carried out according to environmental protection agency methods 9030B and 9034, and the results show that the sulfide concentration in the sludge is less than other fractions of the municipal solid waste treatment plants, which can properly composted, in which sulfides are oxidized to sulfates. Lorry washing sludge could therefore be managed in a municipal solid waste treatment plant.
      PubDate: 2014-10-05
       
  • Phenol removal from aqueous solution by adsorption onto solidified
           landfilled sewage sludge and its modified sludges
    • Abstract: Abstract This study addresses the removal of phenol from aqueous solutions using solidified landfilled sewage sludge and its modified sludges as adsorbents. After the sludge was characterized using instrumental techniques, adsorption studies were performed in a batch system, and the effects of various experimental parameters were evaluated upon phenol adsorption. The characterization results revealed that more irregular pores, higher surface roughness, and a greater content of oxygen-containing functional groups formed in adsorbents derived from ZnCl2 or ZnCl2 and H2SO4 activation. Batch experiments revealed that pH had the weakest effect on phenol adsorption, regardless of the adsorbent type. With increasing adsorbent dosage, the phenol adsorption capacity decreased, and the phenol adsorption rate gradually increased. The maximum adsorption capacity occurred within 120 min, and a first-order kinetic model best described the adsorption. The equilibrium data fitted both the Langmuir and Freundlich isotherm models well, whereas a much higher adsorption capacity and better adsorption strength were observed for phenol adsorption onto adsorbents derived from ZnCl2 or ZnCl2 and H2SO4 activation. The results demonstrated that the solidified landfilled sewage sludge previously modified by activator treatment had a heterogeneous surface and was an effective adsorbent for phenol removal from aqueous solution.
      PubDate: 2014-10-04
       
  • Environmental impact of fly ash utilization in roadway embankments
    • Abstract: Abstract The leaching potential of heavy metals from a roadway embankment constructed of fly ash and soil mixture was studied. Leaching of eight environmentally concerned metals Ag, As, Ba, Cd, Cr, Hg, Pb, and Se from the fly ash–soil mixtures was examined through batch leaching test and column leaching test. The batch leaching test results showed that the fly ash meets the local regulatory standards for beneficial use of nonhazardous wastes. The column leach test revealed that only Ba, Cr, and Se were detectable in the effluents. The peak concentration of Ba in the effluents was much lower than the US EPA Primary Drinking Water Regulations’ maximum contaminant level (MCL). The peak concentrations of Cr and Se exceeded the MCLs only in the initial flush stage and quickly decreased to below the MCLs. Results of this study suggest a great potential for fly ash to be used in roadway embankments to enhance their mechanical properties, reduce the use of soil, and avoid the disposal of fly ash as waste.
      PubDate: 2014-10-01
       
  • Effect of leachate recirculation on the migration of copper and zinc in
           municipal solid waste and municipal solid waste incineration bottom ash
           co-disposed landfill
    • Abstract: Abstract Municipal solid waste incinerator (MSWI) bottom ash was allowed to be disposed of with municipal solid waste (MSW) in landfill sites in the recently enacted standard of China. In this study, three sets of simulated landfill reactors, namely, conventional MSW landfill (CL), conventional MSWI bottom ash and MSW co-disposed landfill (CCL), and leachate recirculated MSWI bottom ash and MSW co-disposed landfill (RCL), were operated to investigate the environmental impact of the co-disposal. The effect of leachate recirculation on the migration of Cu and Zn in the co-disposed landfill was also presented. The results showed that the co-disposal of MSWI bottom ash with MSW would not enhance the leaching of Cu and Zn from landfill. However, the co-disposal increased the Cu and Zn contents of the refuse in the bottom layer of the landfill from 56.7 to 65.3 mg/kg and from 210 to 236 mg/kg, respectively. The recirculation of the leachate could further increase the Cu and Zn contents of the refuse in the bottom layer of the landfill to 72.9 and 441 mg/kg, respectively. Besides these observations, the results also showed that the co-disposed landfill with leachate recirculation could facilitate the stabilization of the landfill.
      PubDate: 2014-10-01
       
  • Humification index of composts originating from three types of woody
           biomass
    • Abstract: Abstract Composting is a good method for recycling surplus manure and stabilizing organic matter from biowastes. Compost is used as a soil amendment and recently, for restoration of vegetation in barren areas. We investigated the relationship between the type of woody biomass (using Robinia pseudoacacia, Japanese larch and apple) and the humification index (HI) of the resulting compost. This study evaluated the difference in HI between the three compost types, and the structural features of composts and extracted humic acids (HAs). The HIs for R. pseudoacacia and apple were larger than that for Japanese larch after composting for 11 months. The structural features of the Japanese larch compost were also different from the apple and R. pseudoacacia, with a very high carbon/nitrogen ratio. The average molecular weights and ultraviolet–visible spectra (A600/C) of HAs extracted from composting samples at 0 and 11 months indicate that the humification rate of Japanese larch was slower than that of R. pseudoacacia and apple. During composting, the average molecular weights of apple and R. pseudoacacia decreased, while their A600/C values increased, but the reverse was observed for Japanese larch. The humification rate was found to depend on the type of woody biomass being composted.
      PubDate: 2014-10-01
       
  • Study of hydrodynamic characteristics in a circulating fluidized bed
           gasifier for plastic waste by computational fluid dynamics modeling and
           simulation
    • Abstract: Abstract For designing an efficient circulating fluidized bed reactor, understanding the complex hydrodynamic characteristics in the reactor is required. Hence, in the present study, the modeling and simulation of the circulating fluidized bed gasifier using plastic waste were carried out with Eulerian-Granular approach. Several cases were investigated as changing superficial gas velocities or sizes of plastic waste particle. Firstly, cases were examined with four different velocities when the particle diameter is 1 mm. At the gas velocity of 6 or 8 m/s, gas volume fraction is more than 95 % throughout the reactor and particle velocity has positive value overall. Therefore, a circulating fluidized bed seems to be formed in both cases. Comparing those two cases, better solid mixing can be expected considering the mass fraction and solid velocity at the superficial gas velocity of 6 m/s. Thus this case was further studied for the effect of particle size. As the diameters of plastic waste particle are 1 or 3 mm, it is considered that a circulating fluidized bed is formed. And plastic waste and sand particles are well mixed throughout the reactor. However, the particle diameter increases over 3 mm then, it is very hard to maintain circulating fluidization condition.
      PubDate: 2014-10-01
       
  • A comparison study on high-temperature water–gas shift reaction over
           Fe/Al/Cu and Fe/Al/Ni catalysts using simulated waste-derived synthesis
           gas
    • Abstract: Abstract A comparative study on Fe/Al, Fe/Al/Cu, and Fe/Al/Ni catalysts in high-temperature water–gas shift reaction (HT–WGS) using simulated waste-derived synthesis gas has been carried out. The metal oxide (Cu and Ni) and aluminum incorporated Fe catalysts were designed to get highly active HT–WGS catalysts. Despite the high CO concentration in the simulated waste-derived synthesis gas, Fe/Al/Cu catalyst exhibited the highest CO conversion (84 %) and 100 % selectivity to CO2 at a very high gas hourly space velocity (GHSV) of 40,057 h−1. The outstanding catalytic performance is mainly due to easier reducibility, the synergy effect of Cu and Al, and the stability of the magnetite.
      PubDate: 2014-10-01
       
  • Characterization of residue from leached cathode ray tube funnel glass:
           reutilization as white carbon black
    • Abstract: Abstract Cathode ray tube (CRT) funnel glass remains an urgent environmental problem and is composed mainly of lead oxide and silicon oxide. In this research, the residue could be obtained from 2 h to 500 rpm activated CRT funnel glass after extracting lead via acid leaching under the conditions of HNO3 concentration 1.0 mol/L, leaching temperature 95 °C and leaching time 1 h. In order to reutilize the residue, its physico-chemical properties were characterized by scanning electron microscopy, Brunauer–Emmett–Teller, thermogravimetric analysis, X-ray diffraction and Fourier transform infrared spectroscopy. The results indicated that the residue was an amorphous superfine powder with approximately 93 wt% silica oxide and specific surface area of more than 170 m2/g. It can be reutilized as white carbon black.
      PubDate: 2014-10-01
       
  • Cobalt separation from waste mobile phone batteries using selective
           precipitation and chelating resin
    • Abstract: Abstract Separation of cobalt from mixed-waste mobile phone batteries containing LiCoO2 cathodic active material was investigated using selective precipitation and chelating resin. Cobalt was recovered from the active powder materials containing 47 % Co oxide together with Mn, Cu, Li, Al, Fe, and Ni oxides. The metal ions were leached sufficiently using 4 M HCl. The metal ions detected spectrophotometrically were removed from the leaching solution by selective precipitation at pH 5.5, with cobalt loss of 27.5 %. Conditions for achieving a recovery of Co in the filtrate by chelating resin were determined experimentally by varying the pH and time of the reaction, as well as the initial resin-to-liquid ratio. The cobalt was efficiently determined by absorption spectrometry at λ max 510 nm. Chelating polyamidoxime resin was synthesized by polymerization of acrylonitrile and followed by amidoximation reaction. Physically cross-linked gel of polyacrylonitrile was made by a cooling technique.
      PubDate: 2014-10-01
       
  • Study on optimal energy efficiency of a sludge drying-incineration
           combined system
    • Abstract: Abstract Thermal drying is a frequently used technology to further remove the water in dewatered sludge. However, it is an expensive solution due to its highly energy consumption. The combination of sludge drying and incineration system, in which, the energy generated from sludge incineration is reused to sludge drying, can largely save the energy consumption of sludge treatment facilities. A bench-scale paddle sludge dryer was built to study the drying characteristics of sludge. Results show that, a significant fluctuation of sludge drying rate and stirring power emerges at the moisture content of 55–65 %. An energy model was established based on a sludge drying and incineration project. The most reasonable dryness of sludge outlet from sludge dryer and input to sludge incinerator was analyzed, in the purpose of achieving optimal energy efficiency. The mono-incineration of dry sludge can be achieved at 850 °C combustion temperature, when sludge lower heating value (LHV) is about 11213 kJ/kg and moisture content is about 60 % w/w. The effect of operation conditions, including sludge moisture content, LHV, and operation load were analyzed based on the energy model. This energy model could be applied for the improvement of energy efficiency of sludge drying and incineration combined system.
      PubDate: 2014-07-30
       
 
 
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