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- Comparative Analysis of Solar Still Types for Enhanced Freshwater
Production: a Multi-Criteria Decision Method Approach-
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Abstract: Abstract Water scarcity is increasing day by day due to population growth, economic development, and environmental pollution. Solar stills present a promising technical solution for purifying water. However, the problem lies in the appropriate choice of the solar still type for the desalination unit, aiming for high productivity and low cost. The objective of this work is to compare five geometrical types of passive solar stills to determine the most suitable and efficient one for freshwater production. First, five solar still geometries were selected based on a literature review. The comparison of these five technologies was conducted using the multi-criteria decision method (MCDM), specifically the TOPSIS method. To achieve this, six technical and economic sub-criteria were taken into account. The preference weights for these sub-criteria were calculated using entropy as the objective method. The results indicate that the cascade solar still ranks first among the other technologies, with a closeness coefficient CCi value of 0.74, followed by the pyramid solar still with a value of 0.56. These results were validated through sensitivity analysis, with a probability of 67% for the cascade solar still and 33% for the pyramid solar still. This analysis allowed us to select the cascade solar still as an efficient solution for freshwater production when compared to other types.
PubDate: 2023-11-23
- Exploring Factors Affecting Sustainable End-of-Life Vehicle Recycling
System: a Structural Equation Modeling Approach-
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Abstract: Abstract Production of automobiles is continuously on the rise in India. This growth in vehicle production increased the generation of end-of-life vehicles. End-of-life vehicle recycling has become a very serious issue in India from environmental, economic, and sustainability perspectives. Hence, it is vital to identify the factors and explore their impact on a sustainable end-of-life vehicle recycling system. The study aims to analyze the relationship among the factors of a sustainable end-of-life vehicle recycling system. This study identified seven factors and developed a conceptual model based on a literature review. A survey of stakeholders in Maharashtra and Gujarat was conducted from February 2022 to October 2022. For this purpose, a questionnaire was distributed online through a Google form link. Structural equation modeling methodology was used to analyze the data of 150 stakeholders and develop the measurement and structural models. The results show a strong relation between the sustainable end-of-life vehicle recycling system and its factors, except those based on the direct impact of government policies and socio-economic measures. The study will help to improve the stakeholders’ understanding of the important measures that need to be taken to develop a sustainable end-of-life recycling system in India. The study will also aid the policy and decision-makers in designing and implementing policies and procedures related to the end-of-life vehicle recycling industry. The research will also help India contribute significantly to the 17 Sustainable Development Goals drafted by the United Nations for all its member nations or ensure a habitable planet for future generations.
PubDate: 2023-11-21
- Implementation of the Deep Eutectic Solvent, Choline Urea Chloride (1:2),
to Evaluate the Sustainability of its Application During CO2 Capture-
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Abstract: Green chemistry aims to create chemical products and processes that decrease or eradicate the need for harmful substances. By using green solvents like Deep Eutectic Solvents (DES) it is feasible to devise new processes or modify current that adhere to the principles of circular economy and green chemistry. In this work is presented the potential use of choline urea chloride (1:2) as a solvent; taking the post-combustion capture of carbon dioxide (CO2) as a case study. The results demonstrated that the methodology proposed allows the thermodynamic modeling of DES, obtaining a prediction of data very similar to the experimental trends previously reported. In addition, the use of DES in CO2 capture allowed a 13.97% reduction in environmental impact and required 25.38% less energy than the traditional process based on amine absorption. This led to a reduction in global cost by 32.11% and 19.64% for equipment and services, respectively, and a 21.13% lower cost of operation. Graphical 
PubDate: 2023-11-21
- Improving Industrial Maintenance Efficiency: a Holistic Approach to
Integrated Production and Maintenance Planning with Human Error
Optimization-
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Abstract: Abstract Integrated production and maintenance planning optimizes efficiency and productivity by coordinating schedules. Investigating this planning can improve operational efficiency, reduce costs, and enhance productivity. It reduces equipment breakdowns, minimizes downtime and delays, and facilitates better resource allocation, thereby lowering costs and enhancing cash flow. On the other hand, human error can significantly affect maintenance operations, reducing performance. This paper introduces a novel mathematical model aimed at cost minimization through the optimization of preventive maintenance (PM) operation planning, production scheduling, and the consideration of human error. Unlike prior research, this research accounts for the influence of human error on both the reduction coefficient of equipment virtual age and associated costs. Besides, this paper categorizes the costs linked to maintenance operations into two distinct groups. The results help decision-makers implement optimal production and maintenance operations in organizations, taking human error into account. Optimal and integrated maintenance and production planning that takes into account human error can have a significant impact on sustainability in several ways. The model is tested in the real world and validated using the sensitivity analysis method. The results suggest that the optimal human error probability, based on its costs, is equal to 0.00005. This finding encourages decision-makers to identify sources of human error and develop proactive measures to optimize performance. Overall, the model can help organizations optimize production and maintenance operations, reduce costs, and improve performance.
PubDate: 2023-11-16
- Energy and Exergy Transfer Diagrams for Visualising Flows in Process
Systems-
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Abstract: Abstract This paper develops a new Exergy Transfer Diagram (ExTD), as an extension of the Energy Transfer Diagram (ETD), to enable the visualisation of both energy and exergy flows within a processing system. Based on Pinch Analysis, the ETD comprises regions in the temperature-enthalpy plot corresponding to the individual heat transfer operations. The position of each operation on the plot provides significant insight into the possible energy savings via retrofit. The ExTD complements the ETD and expresses the exergy flows, enabling the direct targeting of the minimum exergy input to the system and the component-level contributions to total exergy destruction and loss. The ExTD construction uses a Problem Table-based method to provide robust targets for the total exergy destruction of a system. Both the ETD and ExTD tools are demonstrated using an industrial case study of a milk dryer system. Three different utility structures are analysed using the tool including a conventional steam system, a steam system with cogeneration, and a high-temperature heat pump with a supplementary boiler. The results show that the heat pump option achieves the lowest minimum exergy input (4.5 MWx or 1.62 GJx/t) for the system, which represents a 15% reduction in the exergy requirement of the process and, if powered by low GHG-emissions electricity, could achieve a 90% reduction in fossil fuel use and GHG footprint.
PubDate: 2023-11-16
- Central Composite Design Optimization of the Extraction and
Transesterification of Tiger Nut Seed Oil to Biodiesel-
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Abstract: Abstract There is a high demand for sustainable biofuel to curtail the challenges of environmental pollution and scarcity associated with the limited hydrocarbon-based petrol concentrated in certain parts of the globe. In this research, an extraction operation was carried out to obtain tiger nut oil (TNO) using n-hexane. Gas chromatography-mass spectrometry (GC-MS) techniques and Fourier-transform infrared (FTIR) spectroscopy were applied to examine the fatty acid compositions of the bio-oil and subsequent biofuel properties. The interactive effect of significant variables on the extraction and transesterification process was studied. The central composite design result confirmed optimum temperature (55 °C), catalyst weight (3.10 wt%), methanol-to-oil ratio (8:1), and stirring speed (550 rpm) respectively. The output corresponds to 92% biodiesel yield, indicating ± 7.02 standard deviation from the experimental practicable. The kinetic parameters were employed to model a chemical reactor geometry (radius = 3.0 m, reactor length = 9.0 m, mean retention time (MRT) = 3.42, and space-time of 0.30 min) at the optimum conditions. The finding confirmed that the biodiesel properties produced complied with the ASTM-D6751 and EN-141215 specifications, proving to be a reliable feedstock with better fuel properties over TNO-based biodiesel blends (B100, B10, B20, and B30). The research will provide a datum for comparison with other established biodiesel feedstocks and require future investigation in the direction of the vehicular performance level and practicability of the TNO-based feedstock in the internal combustion (IC) engine.
PubDate: 2023-11-15
- A reverse Logistics Inventory Model with Consideration of Carbon Tax
Policy, Imperfect Production, and Partial Backlogging Under a Sustainable
Supply Chain-
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Abstract: Abstract The awareness of consumers for reused or recycled items and environmentally friendly practices has grown over the past few decades, which has encouraged businesses to integrate sustainability development into their operations. As a result, industry’s supply chains are focusing on product recycling, waste reduction initiatives, and proper disposal of expired products. Sustainable development has benefited a variety of industries, including inventory management; it helps to sustain the environment as well as the economy. In this study, the effect of carbon emission on a reverse logistics inventory model is investigated when manufacturing and remanufacturing with multiple retailers are taken into account. In an effort to minimize the carbon emission, many countries are imposing strict limits on carbon emitters. Carbon tax policy is one of the laws that has been successfully implemented in many countries. In this paper, carbon emissions are released from various supply chain activities like product manufacturing, remanufacturing, storage, waste disposal, transportation, and deterioration. To control the excess release of carbon emission, carbon tax regulation is incorporated. During remanufacturing, due to some error, the machine switches from being “in control” to an “out of control” state and generates some imperfect quantities that are instantly inspected and reworked at some cost. Shortages are permitted with partial backlogging, and backlogging rate is constant. The aim of this study is to determine the optimal total cost under a forwards and backwards supply chain system. The model is demonstrated using several numerical examples, followed by a sensitivity analysis that seeks to investigate the impact of key parameters on the optimal solution. Convexity is depicted graphically, and significant features of the results are discussed to extract some management knowledge. The results indicate that the manufacturing cost, remanufacturing cost, and the rate of remanufacturing have a significant impact on the integrated cost of the inventory system. The obtained results also explain that parameters involved in carbon emission activity produce noticeable changes in the total cost. The findings are very managerial and instructive for organizations and businesses seeking environmentally conscious production systems.
PubDate: 2023-11-10
- Multi-Criteria Decision-Making Tools for Project Selection by
International Conglomerates-
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Abstract: Abstract International conglomerates often take financial risks by investing funds in potential projects without conducting comprehensive assessments of the uncertainties associated with economic and political factors, which contribute to overall international business risks. In this study, an analytic hierarchy process (AHP) based approach has been developed as a practical decision-making tool for project selection in project management. The AHP enables the identification of the most valuable projects among various potential options, ensuring that investors benefit from the proposed advantages outlined in the project business plans. The capital expenditure (CAPEX), operating expenditure (OPEX), environment, social and governance (ESG) and ease of business (EOB) are the criteria selected and organised into a hierarchical framework of the AHP. The projects under each criterion are prioritised by assigning overall weights through pairwise matrix comparisons. To ensure the reliability and consistency of the pairwise comparisons, the eigenvector method is employed to evaluate the consistency of the economic freedom sub-criterion under EOB. Similarly, the AHP is applied to the CAPEX, OPEX and ESG criteria using consistent scoring and rating systems for pairwise comparisons, which enables the determination of their overall weights. Based on the analysis, the relative weightage of each decision criterion has been identified, and the score of each project has been estimated. LNG import and re-gasification terminal in Southwest India is chosen as the project with the greatest potential to fulfil the diverse requirements of the companies. Capital cost contributes the most to this decision because the projects considered in this case are highly capital intensive. At the same time, the overall scores of four projects are comparable, and thus, the final decision selection may also be based on the specific priorities of the investors.
PubDate: 2023-11-02
- Pinch Analysis for Land-Constrained Agriculture Sector Planning
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Abstract: Abstract Agriculture is an essential economic sector as it plays an important role in providing growing populations with sufficient food. Thus, it is imperative for policymakers to plan sufficient food stockpiles based on consumption requirements while ensuring lands are used in an efficient manner for producing a range of crops. Land is a limited resource and should be utilised efficiently to meet crop/food production demands. Thus, this work presents land use pinch analysis (LUPA), to aid planning of crop based on land footprint. LUPA is a novel application that allows the decision maker to determine the minimum amount of low land footprint crop required to achieve reductions in land usage and to meet food product demands. To illustrate LUPA, this work provides a numerical case study intended to highlight the benefits and features of the methodology. The case study aims to determine the amount of low land footprint oil crop (e.g., palm oil) that could replace other oil crops to meet a given edible oil demand and achieve reductions in land footprint. Results from the case study suggest that policymakers can opt for around 1 million hectares of low land footprint oil crop to meet the specified edible oil demand and replacing about 8 million hectares of a higher land footprint oil crop in the process. The case study is revisited analyse the impact of crop yield on the planning. This evidently shows that LUPA can be used as a means for strategising land allocation and land use reductions to meet edible oil demands.
PubDate: 2023-11-01
- On the Role of Material Balances in the Synthesis of Overall Process
Control Systems-
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Abstract: Abstract The synthesis of control systems for overall processes remains a challenge. Whilst a number of automated approaches have been explored academically, in practice systems are mainly synthesised using experience and intuition in conjunction with dynamic simulation software. An approach is presented in this paper for the systematic synthesis of overall process control systems which is simple, practical and appropriate for use at the undergraduate teaching level. Many potential problems can be identified and avoided in the synthesis of process control systems by ensuring that the control system can maintain a steady-state control of the overall mass, the mass of the individual components and, where necessary, multiple phases. Processes with recycles are vulnerable to process control problems when the overall mass balance of the system containing the recycle is not correctly managed. This can be overcome by self-regulation (perhaps involving process design changes) or by changing the structure of the control system. Achieving and maintaining the material balance are the main purposes of the majority of controllers in most chemical processes. Without robust delivery of material balance control, higher level control objectives (such as quality controls) are unlikely to be met reliably. This paper presents a step-wise approach to the synthesis of overall process control systems that avoids many potential problems by identifying which process parameters can be manipulated to achieve the intended process mass balance and designing the control structure accordingly.
PubDate: 2023-11-01
- Simultaneous Optimization of Mass Exchanger Networks and Direct
Reuse/Recycle Networks-
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Abstract: Abstract In the past two decades, various process integration methods have been proposed for the optimum synthesis of resource conservation networks, for the recovery of energy and material resources such as water, gas, and solvent. In this paper, a mathematical programming framework is proposed for simultaneous optimization of mass exchanger networks (MENs) and direct reuse/recycle networks (DRNs). Both MEN and DRN synthesis are now relatively established fields with numerous methods developed. Note however that there is a lack of work that considers both areas simultaneously. The newly proposed simultaneous optimization method in this work identifies opportunity for a DRN that allows the material waste to be recycled within the MEN, which is the main novelty of this work. The approach is demonstrated with a vinyl acetate monomer production problem. The latter consists of several mass exchange operations, in which an MEN is synthesized. Opportunity to develop an DRN is also identified, which allows its waste to be recycled without regeneration. Another novelty of the work is that, the supply and target compositions in the MEN problem are expressed in terms of mass ratios as the compositions are relatively large. Results show that the integrated network has a total annualized cost that is reduced by 24.9% as compared to the base case configuration, where both networks were solved independently. This shows the importance of considering entire process systems during process synthesis, as opposed to subsystems independently.
PubDate: 2023-11-01
- Analysis of the Exergy, Economic, and Environmental Impacts and
Performance Enhancement of an Environmentally Friendly Solar Still with
Drop-wise Feeding-
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Abstract: Abstract This paper presents a novel approach for improving the performance of single slope solar still (SSSS) using drop-wise feed water supply. An ecofriendly single slope solar still is fabricated using readily available materials and experimentally investigated at R.E.C. (Rajkiya Engineering College), Azamgarh (latitude 25.7° N, longitude 82.9° E), Uttar Pradesh, India. In this study, drop-wise feed water supply has been chosen as a means of increasing the distillate yield of a solar still. Experiments are performed on two different design modifications of a single slope solar still: design 1 (a conventional solar still) and design 2 (drop-wise feeding of brackish water to the basin of the solar still). Drop-wise feeding of water to the solar still has been used to maintain a lower level of basin water, which improves the mass of distillate produced from the solar still. The performances of both designs of solar stills are compared theoretically and experimentally. In addition, designs 1 and 2 have also been investigated for energy, exergo-economic, and enviroeconomic impacts. The maximum distilled water produced is found to be 2.08 L/m2 and 2.79 L/m2 from designs 1 and 2, respectively. The daily energy efficiency is found to be 18.4% and 24.03% for designs 1 and 2, respectively. For designs 1 and 2, the cost of distilled water is determined to be Rs. 2.91/L, Rs. 2.19/L, with payback periods of 289 days and 218 days, respectively. The exergoeconomic parameters are computed to be 82 W-h/Rs and 138 W-h/Rs for designs 1 and 2, respectively. For designs 1 and 2, the CO2 (carbon dioxide) mitigation values are calculated to be 10.8 and 14.4 t of CO2 based on energy, and 0.29 and 0.51 t of CO2 based on exergy, respectively. The theoretical model of both designs shows acceptable agreement with the experimental results. Based on experimental analysis, design 2 is found to be more efficient and economical compared to design 1. The proposed design modification of drop-wise feeding to solar still produces potable water at a low cost, a high yield, and with environmental benefits. This study makes a valuable contribution to the development of sustainable and affordable water treatment technologies, particularly in regions with limited access to fresh water sources.
PubDate: 2023-11-01
- A New Vendor-Managed Inventory Model by Applying Blockchain Technology and
Considering Environmental Problems-
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Abstract: Abstract One of the most common and successful approaches to integrated supply chain management (SCM) is vendor-managed inventory (VMI). One of the technologies that has been widely used recently to share information in the VMI is blockchain technology (BT). Given that many factors, such as scalability and adoption cost, play a role in obtaining the optimal number of transactions, it is of vital importance to account for them in the VMI. Since the VMI strategy aims for a long-term relationship between the vendor and the retailer and highly affects the supply chain’s total cost, the vendor must pay more attention in selecting retailers. Another contribution of this study is to consider the issue of environmental pollution generated by inventory holding, ordering, set-up, and transportation operations, which has not been thoroughly investigated in the existing literature. This study uses a green two-echelon multi-product, multiple-vendor, and multiple-retailer supply chain with a hybrid of multi-criteria decision-making (MCDM) methods, and a multi-objective programming under the VMI policy is developed. This paper examines BT for supply chain management by accounting for the most impactful criteria of BT implementation in retailer selection and optimization. For this purpose, this paper applies the Bayesian best–worst approach (BWM) as one of the MCDM techniques. The obtained weights are then plugged into the model as the inputs of the proposed model. Finally, the efficiency of the presented method is verified through a case study with actual data collected from the electronic supply chain.
PubDate: 2023-11-01
- Impact of Carbon Emission and Volume Flexibility on a Reverse Logistics
Inventory Model with Two Levels of Trade Credit Period-
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Abstract: Abstract In recent years, the majority of business organizations have concentrated on product recycling, waste reduction initiatives and the proper disposal of expired products due to government regulations and consumer concerns about environmental issues. In this study, a reverse logistics inventory model for multi-retailers is taken into consideration, along with the effect of carbon emission from product manufacturing, remanufacturing, storage and deterioration. To regulate the release of carbon emissions from various sources, a carbon tax regulation has been implemented. Volume flexibility (which allows production to be reduced or increased in response to observed demand) plays an essential role in supply chain management; by implementing this, supply chain managers can control the risk of imperfect production which often occurs due to machinery problems. Also, they can reduce some costs by using flexible labour resources (hiring temporary workers instead of permanent workers). In this paper, a producer-retailer-customer supply chain system is developed in which the producer, as well as the retailer, offers a trade credit policy in order to stimulate sales and reduce inventory. This policy serves as an incentive tool to attract new customers and boost the business. The aim of this paper is to find the optimal value of total cost under a forward and backward supply chain system. An algorithm is provided in order to solve the optimization problem, which generates the optimal solution for optimal time and production rate, thereby minimizing the total integrated cost. Convexity is depicted graphically, and numerical examples are used to describe the applicability of the proposed model. Finally, a sensitivity analysis has been performed for various parameters of the inventory model, where the impact of each parameter on the optimal solution is shown to extract some management knowledge. The findings are very managerial and instructive for organizations and businesses seeking environmentally conscious production systems.
PubDate: 2023-11-01
- Thermal Characterization of Flat Plate Solar Collector Using Titanium
Dioxide Nanofluid-
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Abstract: Abstract The thermal performance of flat plate collectors (FPCs) using titanium dioxide (TiO2) nanofluids is analyzed numerically using fluent and SolTrace. The solar ray tracing is performed on SolTrace to obtain the average solar flux on the absorber plate in FPC. The numerical study is conducted on the flat plate solar collector with an aperture width of 200 mm and a single absorber tube of 12.7 mm inner diameter. The numerical simulation on fluent is performed for TiO2 nanofluids with a percentage volume of 0%, 2%, 3%, and 4% TiO2 in Therminol as a heat transfer fluid (HTF). The study also includes the effect of the inlet temperature of nanofluids on the thermohydraulic performance of solar FPC. The result shows a 56% drop in thermal efficiency with a temperature increase from 300 to 353 K. However, changes in the Nusselt number (Nu) and convective heat transfer rate were found to be negligible. The analysis also includes the effect of the Reynolds number (Re) on thermal efficiency and friction factor (f) for different volume fractions of TiO2 in Therminol. A 22.2% increase in thermal efficiency and a 17.5% increase in friction factor are found for a 4% volume fraction of TiO2 in Therminol at a Reynolds number of 720. However, a 17.3% increase in thermal efficiency is found for a 4% volume fraction of TiO2 at a higher Reynolds number of 1080.
PubDate: 2023-11-01
- Structure and Content of BEng Chemical Engineering Programmes in the UK,
Relative to the Frontiers in Chemical Engineering Education Model-
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Abstract: Abstract The Frontiers in Chemical Engineering Education initiative in the USA in the early 2000s proposed a reformed chemical engineering curriculum organised around the three themes of Molecular transformations, Multiscale analysis and a Systems view. It was subsequently observed that few departments in the USA had adopted this structure for their programmes, although several UK programmes appeared already to feature this structure. Therefore, the objective of the current work was to analyse BEng chemical engineering programmes in the UK relative to this tripartite structure, in order to evaluate to what extent the Frontiers model was already represented within UK chemical engineering education. From the 28 UK universities offering IChemE-accredited programmes, the structure and content of 24 BEng programmes were analysed against the tripartite Frontiers structure. All 24 programmes broadly followed the Frontiers structure. The greatest variation between programmes was in the amount of content contributing to the Molecular transformations theme, which varied from 1.4 to 26%. This was also the smallest of the three themes, contributing on average around 10%, compared with 37% for Multiscale analysis and 38% for Systems, with 10% coming from Supporting Competences (such as laboratory and professional skills) and 5% from Other subjects (such as mechanical or electrical engineering or electives). Molecular transformations was generally most prominent in the first year, the second year tended to contribute the most Multiscale analysis content and the final year was dominated by Systems. The Institution of Chemical Engineers’ Accreditation guidance tends to encourage the high Systems emphasis and low Molecular transformations component, in contradiction to the recommendations of the Frontiers initiative. Optional electives and MEng specialisms feature Molecular transformations emphases, the latter less so than in the 2000s, since when the drivers for curriculum development have moved from biosciences and nanotechnology towards energy and sustainability.
PubDate: 2023-11-01
- A Comprehensive Review on Rare Biodiesel Feedstock Availability, Fatty
Acid Composition, Physical Properties, Production, Engine Performance and
Emission-
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Abstract: Abstract The world is now experiencing the first real global energy crisis, the effects of which will be felt for many years to come. Fossil fuels have accounted for more than 80% of the world’s energy requirements for decades. The cost of coal has reached record highs, while the price of oil reached at it’s peak in the middle of 2022 at well over 100 US dollars per barrel before declining. Rising energy costs of fossil fuels are driving a significant wealth shift from consumers to producers. The primary causes of the growing level of carbon dioxide in the atmosphere are fossil fuels. Stated Policy Scenario predicts a 1% annual growth in primary energy demand through 2030, which will be mostly satisfied by greater usage of renewable energy sources. Biodiesel is gaining popularity as a means of supplying energy since it is a renewable fuel, non-toxic, biodegradable, and locally available using recycled or agricultural materials with a lesser environmental effect. Biodiesel refers to a non-petroleum-based diesel fuel consisting of short-chain esters, made by using numerous resources, which can be used (alone or blended with conventional diesel) in an unmodified diesel engine. The greenhouse gas emission for biodiesel is 74% lesser as compared to diesel fuel. With the widespread implementation of blending rules, the usage of biofuels rises to 5.5 million barrels of oil equivalent per day (mboe/day) in 2030 from 2.2 mboe/day in 2022. This study explores the numerous rare biodiesel feedstock, production, fatty acid content, physical properties and their effect on diesel engine output behaviour. These resources contain a large amount of free fatty acids and triglycerides which are usually used in the preparation of biodiesel. Since biodiesel has a higher oxygen content and a lower energy content than diesel fuel, it often offers better brake thermal efficiency, brake specific fuel consumption, NOx emission, and decreased HC, CO and smoke emissions at some blending ratio. The exhaust gas recirculation assembly in the engine reduces the NOx emission. The incorporation of non-additive in biodiesel blend acts as a catalyst during the combustion process and improves engine combustion by increasing the surface area of combustion. Biodiesel is clean energy and can be a promising future energy source for diesel engines.
PubDate: 2023-11-01
- A New Chemical Engineering Curriculum for a New South Africa: Assessing
the Impact of Duncan Fraser’s Three Decades of Educational Research and
Reform-
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Abstract: Abstract Engineering education research is a relatively new field focused on improving engineering education to support the success of a broader range of students and be more relevant to the needs of contemporary society. In this article, we look closely at the impact of a pioneer in this field, the late Professor Duncan McKenzie Fraser, who began a focused and scholarly programme of work during late apartheid in South Africa, looking closely at the challenges experienced by chemical engineering students at the University of Cape Town (UCT), where he worked. We analyse Duncan’s early experiments in improving teaching and curriculum which led into a recognized body of engineering education research. These research findings informed a programme of curriculum reform at UCT, the first phase of which involved the creation of some new courses and the modification of parts of the curriculum, and the second phase of which involved a full-scale reform of the entire curriculum. The analysis shows how engineering education research was used to inform innovative curriculum design that was closely attuned to contextual needs, specifically regarding stark racial disparities in student success, and also evolved later to embody a focus on sustainable development. Overall, there are significant lessons for the growing field of engineering education, which continues to grapple with the disjoint between research and improved practice—crucially showing the need for long term engagement, as exemplified in this programme of work which spanned over three decades.
PubDate: 2023-11-01
- Selecting Green Suppliers by Considering the Internet of Things and CMCDM
Approach-
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Abstract: Abstract Selecting the suppliers in a green supply chain (GSC) improves supply chain capabilities by considering environmental policies. On the other hand, considering the development of technology and intelligence of the Internet of Things (IoT) and their help to meet goals better, it is essential to study them in this area. So, it is crucial to identify the influential factors of the IoT in selecting a green supplier and find its most important criteria for further monitoring and control. This paper aims to illustrate the ability of four different combinatorial multi-criteria decision-making (CMCDM) techniques in determining the best supplier in the rubber GSC. The suppliers are weighted using the fuzzy hierarchical analysis (FAHP) method, then ranked using four methods: VIKOR, TOPSIS, ELECTERE, and WASPAS. Then, their ranks are compared with each other. Eventually, Spearman’s rank correlation was examined to compare CMCDM methods. The results indicate that there is a similar ranking between all four CMCDM methods. Finally, it was found the second supplier is the best alternative for rubber companies looking for environmentally friendly suppliers. Also, FAHP-ELECTERE and FAHP-WASPAS methods have a high correlation with each other. The developed method can help decision-makers to make prompt decisions with less environmental pollution, which helps to achieve sustainable performance in the entire supply chain.
PubDate: 2023-11-01
- State Assessment Method of Electricity Meter Based on Grey Correlation
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Abstract: Abstract With the rapid development of smart grid construction, the coverage of electricity meters has been greatly improved, so it is particularly important to conduct a reasonable evaluation of the running state of electricity meters. This paper presents a method of electricity meter running state assessment based on grey correlation analysis. Firstly, according to the multi-level and multi-factor of the state information of electricity meters, the state evaluation index system of electricity meters is established from four aspects: operation reliability, historical faults, power grid operating environment, and external operating environment. Secondly, entropy weight method is used to determine the weight of each evaluation index. Finally, grey correlation analysis is used to calculate the Euclidean distance and grey correlation degree between the state of the electricity meters to be evaluated and the optimal and the worst ideal state respectively. By combining the Euclidean distance and grey correlation degree, the relative closeness degree of each evaluated sample will be obtained, and finally, the state of the electricity meter to be evaluated will be obtained. It can be seen from the case analysis that this evaluation method can not only effectively reflect the running state of electricity meters, but also sort the running state of different electricity meters to be evaluated, so as to provide an effective reference for reasonably arranging the maintenance cycle of electricity meters and guiding the maintenance of electricity meters.
PubDate: 2023-11-01
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