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Records with Subject: Process Design
Showing records 1 to 25 of 208. [First] Page: 1 2 3 4 5 Last
Optimization of the Production Technology of Oxidized Cyclodextrin Bisulfite
Yana-Ya Kostyro, Anastasiya Soldatenko, Alexey Levchuk
September 13, 2019 (v1)
Keywords: active pharmaceutical ingredient, cyclodextrin, oligosaccharides, oxidation of carbohydrates, production technology, sodium periodate
The A.E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences has developed an original active pharmaceutical ingredient based on an oxidized cyclodextrin oligosaccharide, which is a bisulfite derivative. Conducted pharmacological studies proved its antiviral activity in vitro and in vivo experiments against the influenza A (H1N1) virus. The aim of this work was to optimize the technology of obtaining the active pharmaceutical ingredient based on the bisulfite derivative of oxidized cyclodextrin to increase the efficiency and safety of the process. For this, a scaled method of oligosaccharide oxidation was tested on pilot plants in accordance with the requirements of green chemistry. As a result, the reaction time was reduced from three to five days (laboratory conditions) to 1.5 h, and the safety and environmental friendliness of process was ensured. The use of cross-flow filtration and the method of freeze-drying eliminated 96% of ethyl alcohol,... [more]
Utility Paths Combination in HEN for Energy Saving and CO2 Emission Reduction
Abdelbagi Osman, Mohanad Eltayeb, Fahd Rajab
September 13, 2019 (v1)
Keywords: CO2 emission, energy saving, HEN retrofit, path analysis, paths combination
Energy demand and flue gas emissions, namely carbon dioxide (CO2) associated with the industrial revolution have exhibited a continuous rise. Several approaches were introduced recently to mitigate energy consumption and CO2 emissions by either grass root design or retrofit of existing heat exchanger networks (HEN) in chemical process plants. In this work, a combinatorial approach of path combination is used to generate several options for heat recovery enhancement in HEN. The options are applied to successively shift heat load from HEN utilities using combined utility paths at different heat recovery approach temperature (HRAT) considering exchangers pressure drop. Industrial case study for HEN of the preheat train in crude oil distillation unit from the literature is used to demonstrate the approach. The obtained results have been studied economically using the cost targeting of Pinch Technology. As a result, both external energy usage and CO2 emissions have been reduced from a heate... [more]
Innovative Effluent Capture and Evacuation Device that Increases COD Removal Efficiency in Subsurface Flow Wetlands
Pedro Cisterna-Osorio, Verónica Lazcano-Castro, Gisela Silva-Vasquez, Mauricio Llanos-Baeza, Ignacio Fuentes-Ortega
September 13, 2019 (v1)
Keywords: artificial wetlands, horizontal wetland, subsurface flow
The objective of this work is to evaluate the impact of innovative modifications made to conventional effluent capture and discharge devices used in subsurface flow wetlands (SSFW). The main modifications that have been developed extend the influence of the capture and discharge device in such a way that the SSFW width and height are fully covered. This improved innovative device was applied and evaluated in two subsurface flow wetlands, one on a pilot scale and one on a real scale. To evaluate the impact of the innovative device with respect to the conventional one in the operational functioning of subsurface flow wetlands, the elimination of chemical oxygen demand (COD) was measured and compared. The results show that for the innovative device, the COD removal was 10% higher than for the conventional device, confirming the validity and effectiveness of the modifications implemented in the effluent capture and discharge devices used in SSFW.
Improvement of 1,3-Butadiene Separation in 2,3-Butanediol Dehydration Using Extractive Distillation
Daesung Song, Young-Gak Yoon, Seung-Kwon Seo, Chul-Jin Lee
September 5, 2019 (v1)
Keywords: 1-butene, 1,3-butadiene, 2,3-butanediol dehydration, Distillation, economic feasibility, extractive distillation
This study was performed to investigate the extractive distillation for 1,3-butadiene (1,3-BD) purification as a part of the 2,3-butanediol (2,3-BDO) dehydration process. The separation of 1,3-BD from 1-butene produced as a 2,3-BDO dehydration by-product while using distillation is complicated due to the similar volatilities of the two compounds. Thus, an extractive distillation system is proposed for the effective recovery of 1,3-BD, and is compared with a conventional distillation system in terms of its performance and economic feasibility. A higher 1,3-BD recovery rate was achieved while using the proposed system and the relative profitabilities of both separation systems were analyzed according to the market price of 1,3-BD, which is a decisive variable for economic feasibility.
CO2 Hydrogenation to Methanol by a Liquid-Phase Process with Alcoholic Solvents: A Techno-Economic Analysis
Harri Nieminen, Arto Laari, Tuomas Koiranen
September 5, 2019 (v1)
Keywords: alcohol promoted, CO2 hydrogenation, liquid-phase process, methanol synthesis, process simulation, Technoeconomic Analysis
Synthesis of methanol from recirculated CO2 and H2 produced by water electrolysis allows sustainable production of fuels and chemical storage of energy. Production of renewable methanol has, however, not achieved commercial breakthrough, and novel methods to improve economic feasibility are needed. One possibility is to alter the reaction route to methanol using catalytic alcoholic solvents, which makes the process possible at lower reaction temperatures. To estimate the techno-economic potential of this approach, the feasibilities of the conventional gas-phase process and an alternative liquid-phase process employing 2-butanol or 1-butanol solvents were compared by means of flowsheet modelling and economic analysis. As a result, it was found that despite improved methanol yield, the presence of solvent adds complexity to the process and increases separation costs due to the high volatility of the alcohols and formation of azeotropes. Hydrogen, produced from wind electricity, was the m... [more]
Exergy Analysis and Evaluation of the Different Flowsheeting Configurations for CO2 Capture Plant Using 2-Amino-2-Methyl-1-Propanol (AMP)
Ebuwa Osagie, Aliyu M. Aliyu, Somtochukwu Godfrey Nnabuife, Osaze Omoregbe, Victor Etim
August 15, 2019 (v1)
Keywords: 2-Amino-2-Methyl-1-Propanol, exergy analysis, flowsheeting configurations, modelling and Simulation, post-combustion capture
This paper presents steady-state simulation and exergy analysis of the 2-amino-2-methyl-1-propanol (AMP)-based post-combustion capture (PCC) plant. Exergy analysis provides the identification of the location, sources of thermodynamic inefficiencies, and magnitude in a thermal system. Furthermore, thermodynamic analysis of different configurations of the process helps to identify opportunities for reducing the steam requirements for each of the configurations. Exergy analysis performed for the AMP-based plant and the different configurations revealed that the rich split with intercooling configuration gave the highest exergy efficiency of 73.6%, while that of the intercooling and the reference AMP-based plant were 57.3% and 55.8% respectively. Thus, exergy analysis of flowsheeting configurations can lead to significant improvements in plant performance and lead to cost reduction for amine-based CO2 capture technologies.
Performance Evaluation of Sustainable Soil Stabilization Process Using Waste Materials
Muhammad Aamir, Zarnish Mahmood, Aqsa Nisar, Amjad Farid, Tanveer Ahmed Khan, Mudassir Abbas, Muhammad Ismaeel, Syyed Adnan Raheel Shah, Muhammad Waseem
August 15, 2019 (v1)
Keywords: processes, stabilization, strength improvement, sustainable, waste management
The process of soil stabilization is a fundamental requirement before road infrastructure development is possible. Different binding materials have been used worldwide as soil stabilizers. In this study, water treatment waste (i.e., alum sludge (AS)) was used as a soil stabilizer. Alum sludge can work not only as a low-cost soil stabilizer but also can solve the problem of waste management at a large scale. Utilization of alum waste can be a sustainable solution and environmentally friendly exercise. Thus, in consideration of the pozzolanic properties of alum, it was applied as a binder, similar to cement or lime, to stabilize the soil with the addition of 2%, 4%, 6%, 8%, and 10% of dry soil by weight. To analyze the resulting improvement in soil strength, the California Bearing Ratio (CBR) test was conducted in addition to three other tests (i.e., particle size analysis, Atterberg’s limits test, and modified proctor test). The soil bearing ratio was significantly improved from 6.53% t... [more]
Design and Optimization of a Process for the Production of Methyl Methacrylate via Direct Methylation
Taotao Liang, Xiaogang Guo, Abdulmoseen Segun Giwa, Jianwei Shi, Yujin Li, Yan Wei, Xiaojuan Wang, Xuansong Cao, Xiaofeng Tang, Jialun Du
August 15, 2019 (v1)
Keywords: double-effect distillation, energy conservation, MAL, MMA, purity
Methyl methacrylate (MMA) plays a vital role in national productions with broad application. Herein, the production of MMA is realized by the improved eco-friendly direct methylation method using Aspen Plus software. Three novel kinds of energy-saving measures were proposed in this study, including the recycle streams of an aqueous solution, methacrolein (MAL), and methanol, the deployment of double-effect distillation instead of a normal one, and the design of a promising heat-exchange network. Moreover, MMA with a purity of 99.9% is obtained via the design of a MAL absorber column with an optimal stage number of 11 and a facile chloroform recovery process by using the RadFrac model. Thus, the proposed green process with energy-conservation superiority is the vital clue for developing MMA, and provides a reference for the production of MMA-ramifications with excellent prospects.
Modeling of a Double Effect Heat Transformer Operating with Water/Lithium Bromide
Itzel N. Balderas-Sánchez, J. Camilo Jiménez-García, Wilfrido Rivera
August 14, 2019 (v1)
Keywords: absorption heat transformer, COP enhancement, thermal energy upgrade, water-lithium bromide
Absorption heat transformers are effective systems for a wide variety of applications; however, their main purpose is to upgrade thermal energy from several sources at low-temperature up to a higher temperature level. In the literature, several advanced configurations for absorption heat transformers have been reported which are mainly focused on the improvement of the gross temperature lift by the use of a double absorption process; however, these systems usually offer a reduced coefficient of performance. The present study proposes a new advanced configuration of an absorption heat transformer that improves the coefficient of performance utilizing a double generation process. The operation of the new configuration was numerically modeled, and the main findings were discussed and presented emphasizing the effect of several parameters on the system performance. The highest coefficient of performance and gross temperature lift were 0.63 and 48 °C, respectively. From its comparison with... [more]
Optimization of Post Combustion CO2 Capture from a Combined-Cycle Gas Turbine Power Plant via Taguchi Design of Experiment
Ben Alexanda Petrovic, Salman Masoudi Soltani
August 8, 2019 (v1)
Keywords: Aspen Plus, Carbon Dioxide Capture, CCGT, Minitab, Optimization, Taguchi
The potential of carbon capture and storage to provide a low carbon fossil-fueled power generation sector that complements the continuously growing renewable sector is becoming ever more apparent. An optimization of a post combustion capture unit employing the solvent monoethanolamine (MEA) was carried out using a Taguchi design of experiment to mitigate the parasitic energy demands of the system. An equilibrium-based approach was employed in Aspen Plus to simulate 90% capture of the CO2 emitted from a 600 MW natural gas combined-cycle gas turbine power plant. The effects of varying the inlet flue gas temperature, absorber column operating pressure, amount of exhaust gas recycle, and amine concentration were evaluated using signal to noise ratios and analysis of variance. The optimum levels that minimized the specific energy requirements were a: flue gas temperature = 50 °C; absorber pressure = 1 bar; exhaust gas recirculation = 20% and; amine concentration = 35 wt%, with a relative im... [more]
Syngas Production from Combined Steam Gasification of Biochar and a Sorption-Enhanced Water−Gas Shift Reaction with the Utilization of CO2
Supanida Chimpae, Suwimol Wongsakulphasatch, Supawat Vivanpatarakij, Thongchai Glinrun, Fasai Wiwatwongwana, Weerakanya Maneeprakorn, Suttichai Assabumrungrat
August 8, 2019 (v1)
Keywords: gasification, multi-functional material, sorption-enhanced water–gas shift
This research aims at evaluating the performance of a combined system of biochar gasification and a sorption-enhanced water−gas shift reaction (SEWGS) for synthesis gas production. The effects of mangrove-derived biochar gasification temperature, pattern of combined gasification and SEWGS, amount of steam and CO2 added as gasifying agent, and SEWGS temperature were studied in this work. The performances of the combined process were examined in terms of biochar conversion, gaseous product composition, and CO2 emission. The results revealed that the hybrid SEWGS using one-body multi-functional material offered a greater amount of H2 with a similar amount of CO2 emissions when compared with separated sorbent/catalyst material. The gasification temperature of 900 °C provided the highest biochar conversion of ca. 98.7%. Synthesis gas production was found to depend upon the amount of water and CO2 added and SEWGS temperature. Higher amounts of H2 were observed when increasing the amount of w... [more]
Manufacturing Process, In Vivo and In Vitro Digestibility Assessment of an Enteral Feeding Product Hydrolyzed from Locally Available Ingredients Using Commercial Enzymes
Nguyen Thi Quynh Hoa, Luu Ngan Tam, Luu Van Thien Phu, Than Van Thai, Duy Chinh Nguyen, Dong Thi Anh Dao
August 8, 2019 (v1)
Keywords: hydrolyzed protein, in vivo digestibility, pepsin digestibility, ready-to-use enteral feeding product, Swiss mice
A ready-for-use enteral feeding product was manufactured based on energy standard mixing using hydrolyzed products from local foods (i.e., loin pork, carrot, pumpkin, soybean, rice, and potato). When compared to enteral foods based on defined ingredients, the manufactured product is more cost-effective, appropriately functional and has similar physicochemical properties. Relative protein digestibility for in vitro value was tested by using enzyme pepsin, pH-drop and pH-stat method with three different enzymes. The product was shown to be easily digested with an in vivo digestibility value of 89.7%. Molecule sizes of components in the product ranged from 3.5 to 8.5 kDa, determined by SDS-PAGE, and the average molecular weight was 1.52 kDa, determined by Gel Permeation Chromatography (GPC) method. In terms of nutritional value, the product achieved a caloric density of 1 kcal/mL, dietary fibers of 1.48 g per 100 mL and provided both oligomeric and monomeric forms of protein. In addition,... [more]
Optimal Design of a Carbon Dioxide Separation Process with Market Uncertainty and Waste Reduction
Juan Pablo Gutierrez, Eleonora Erdmann, Davide Manca
August 7, 2019 (v1)
Keywords: carbon dioxide separation, economic uncertainty, environmental impact, market prediction, optimal conceptual design
The aim of this work is to optimize the conceptual design of an amine-based carbon dioxide (CO2) separation process for Enhanced Oil Recovery (EOR). A systematic approach is applied to predict the economic profitability of the system while reducing the environmental impacts. Firstly, we model the process with UniSim and determine the governing degrees of freedom (DoF) through a sensitivity analysis. Then, we proceed with the formulation of the economic problem, where the employment of econometric models allows us to predict the highest dynamic economic potential (DEP). In the second part, we apply the Waste Reduction (WAR) algorithm to quantify the environmental risks of the studied process. This method is based on the minimization of the potential environmental indicator (PEI) by using the generalization of the Waste Reduction algorithm. Results show that the CO2 separation plant is promising in terms of economic revenues. However, the PEI value indicates that the higher the profitabi... [more]
Scaling Relations in Modular Process Design
Michael Baldea, Burke A. Snowden, Tam T. Do, Calvin Tsay
August 6, 2019 (v1)
Keywords: Process Design, Process Modularization
This presentation deals with the issue of modularization of chemical plants, defined in the sense of designing smaller-capacity facilities (“modules”) that could be used to process geographically-distributed resources or serve distributed customers. Using established scaling relations, it is demonstrated that technologies that scale up well (i.e., for which capital cost increases sublinearly with capacity) scale down poorly, and vice versa. A further analysis of scale-down and modularization is carried out from the perspective of scaling of individual unit operations and their contribution to the plant cost stack. Following the same line of reasoning, it is shown that units that scale down well will scale up poorly and vice-versa. On this basis, it is argued that scaling relations can be used not only to guide the design of modular processes based on existing technology, but also to direct research towards new designs that alleviate the cost problems associated with units that have poo... [more]
The Influence and Optimization of Geometrical Parameters on Coast-Down Characteristics of Nuclear Reactor Coolant Pumps
Yuanyuan Zhao, Xiangyu Si, Xiuli Wang, Rongsheng Zhu, Qiang Fu, Huazhou Zhong
August 5, 2019 (v1)
Keywords: coast-down characteristics, geometrical parameters, multiple linear regression, reactor coolant pump, transition process
Coast-down characteristics are the crucial safety evaluation factors of nuclear reactor coolant pumps. The energy stored at the highest moment of inertia of the reactor coolant pump unit is utilized to maintain a normal coolant supply to the core of the cooling loop system for a short period of time during the coast-down transition. As a result of the high inertia moment of the rotor system, the unit requires a high reliability of the nuclear reactor coolant pump and consumes considerable energy in the start-up and normal operation. This paper considers the operational characteristics of the coast-down transition process based on the existing hydraulic model of the nuclear reactor coolant pump. With the implementation of an orthogonal test, the hydraulic performance of the nuclear reactor coolant pump was optimized, and the optimal combination of impeller geometrical parameters was selected using multivariate linear regression to prolong the coast-down time of the reactor coolant pump... [more]
Optimization of Distillation Sequences with Nonsharp Separation Columns
Xi Wang, Zengzhi Du, Yunlu Zhang, Jingde Wang, Jianhong Wang, Wei Sun
August 5, 2019 (v1)
Keywords: Aspen, nonsharp distillation sequence, Optimization
Nonsharp distillation sequences are widely used in industrial separation processes; however, most current research has not discussed this topic, except in sequences with heat integration under special operating conditions, including complex columns. The sequence with nonsharp separation has the features of general distillation sequences, which are usually optimized by adjusting the separation sequence and the design/operation parameters of each column in the sequence, making the optimization a mixed integer nonlinear programming (MINLP) problem, which is usually hard to solve. With inclusion of nonsharp separation columns, the sequence optimization becomes even more complicated and computationally intensive. This work aimed to optimize the distillation sequence, including nonsharp distillation alongside simple columns and dividing wall columns. Inspired by the dynamic programing method for sharp distillation sequence, a framework for automatic optimization is proposed to decompose the... [more]
Model-Based Design and Process Optimization of Continuous Single Pass Tangential Flow Filtration Focusing on Continuous Bioprocessing
Maximilian J. Huter, Jochen Strube
August 5, 2019 (v1)
Keywords: Continuous Bioprocessing (CBP), Conceptual Process Design (CPD), Single-Pass-Tangential-Flow-Filtration (SPTFF), modelling, ultrafiltration
In this study the Single-Pass-Tangential-Flow-Filtration (SPTFF) concept for continuous ultrafiltration in bioprocessing is investigated. Based on a previously validated physico-chemical model for a single ultrafiltration cassette, the transfer to a multistage SPTFF is predicted and validated experimentally by concentration steps for bovine serum albumin (BSA) and the monoclonal antibody immunoglobulin G (IgG) are compared. The model applied for the ultrafiltration membrane contains the Stagnant Film Model (SFM) for concentration polarization, as well as the Osmotic Pressure Model (OPM) and the Boundary Layer Model (BLM) for the mass transfer through the membrane. In addition, pressure drop correlations as a function of the Reynolds number are included to describe the development of the transmembrane pressure over the length of the module. The outcome of this study shows the potential to improve this multi-parameter dependent unit operation by a model-based optimization allowing signif... [more]
Aeration Process in Bioreactors as the Main Energy Consumer in a Wastewater Treatment Plant. Review of Solutions and Methods of Process Optimization
Jakub Drewnowski, Anna Remiszewska-Skwarek, Sylwia Duda, Grzegorz Łagód
July 31, 2019 (v1)
Keywords: activated sludge, aeration process, bioreactors, energy consumption, nutrient removal, wastewater treatment processes
Due to the key role of the biological decomposition process of organic compounds in wastewater treatment, a very important thing is appropriate aeration of activated sludge, because microorganisms have to be supplied with an appropriate amount of oxygen. Aeration is one of the most energy-consuming processes in the conventional activated sludge systems of wastewater treatment technology (may consume from 50% to 90% of electricity used by a plant), which makes it the most cost-generating process incurred by treatment plants. The paper presents the construction of aeration systems, their classification as well as parameters and factors that significantly affect the aeration process e.g., oxygen transfer efficiency, diffuser fouling, methods of dealing with diffuser fouling, diffuser selection. Additionally, there are briefly presented “smart control” systems in wastewater treatment and effect of application control strategy based on Supervisory Control and Data Acquisition system connect... [more]
Modeling of Wastewater Treatment Processes in Membrane Bioreactors Compared to Conventional Activated Sludge Systems
Marta Bis, Agnieszka Montusiewicz, Adam Piotrowicz, Grzegorz Łagód
July 31, 2019 (v1)
Keywords: activated sludge, computer simulation, membrane techniques, wastewater treatment processes
Membrane techniques constitute an interesting alternative to conventional activated sludge systems (CAS). In membrane bioreactors (MBR), the biomass separated on membranes is retained independently of sludge sedimentation properties. As a consequence, a high biomass concentration as well as low food to microorganisms ratio can be obtained. Moreover, the development of a characteristic activated sludge population is stimulated by the specific conditions prevailing in MBRs. In the study, the operation and treatment efficiency of the MBR and CAS processes were examined and compared. Simulation was performed with the use of GPS-X software. The effluent quality obtained for the MBR system was either better or comparable to that of CAS. The most significant difference concerned the elimination of total suspended solids, which amounted to 99.8% in the MBR. Regarding nutrients, a low concentration of total phosphorus in the effluent from CAS and MBR was obtained (0.67 gP m−3 and 0.50 gP m−3, r... [more]
Conceptual Design of Pyrolytic Oil Upgrading Process Enhanced by Membrane-Integrated Hydrogen Production System
Bo Chen, Tao Yang, Wu Xiao, Aazad khan Nizamani
July 31, 2019 (v1)
Keywords: hydrogen production, process modeling, pyrolytic oil hydro-processing, Syngas
Hydrotreatment is an efficient method for pyrolytic oil upgrading; however, the trade-off between the operational cost on hydrogen consumption and process profit remains the major challenge for the process designs. In this study, an integrated process of steam methane reforming and pyrolytic oil hydrotreating with gas separation system was proposed conceptually. The integrated process utilized steam methane reformer to produce raw syngas without further water−gas-shifting; with the aid of a membrane unit, the hydrogen concentration in the syngas was adjusted, which substituted the water−gas-shift reactor and improved the performance of hydrotreater on both conversion and hydrogen consumption. A simulation framework for unit operations was developed for process designs through which the dissipated flow in the packed-bed reactor, along with membrane gas separation unit were modeled and calculated in the commercial process simulator. The evaluation results showed that, the proposed proces... [more]
Innovation in Continuous Rectification for Tequila Production
Estarrón-Espinosa Mirna, Ruperto-Pérez Mariela, Padilla-de la Rosa José Daniel, Prado-Ramírez Rogelio
July 31, 2019 (v1)
Keywords: energy saving, horizontal continuous distillation, rectification, tequila
In this study, a new process of continuous horizontal distillation at a pilot level is presented. It was applied for the first time to the rectification of an ordinario fraction obtained industrially. Continuous horizontal distillation is a new process whose design combines the benefits of both distillation columns, in terms of productivity and energy savings (50%), and distillation stills in batch, in terms of the aromatic complexity of the distillate obtained. The horizontal process of continuous distillation was carried out at the pilot level in a manual mode, obtaining five accumulated fractions of distillate that were characterized by gas chromatography (GC-FID). The tequila obtained from the rectification process in this new continuous horizontal distillation process complies with the content of methanol and higher alcohols regulated by the Official Mexican Standard (NOM-006-SCFI-2012). Continuous horizontal distillation of tequila has potential energy savings of 50% compared to... [more]
A Novel Method of Sustainability Evaluation in Machining Processes
Haiming Sun, Conghu Liu, Jianqing Chen, Mengdi Gao, Xuehong Shen
July 30, 2019 (v1)
Keywords: conversion efficiency, emergy, machining process, Renewable and Sustainable Energy
In order to quantitatively evaluate and improve the sustainability of machining systems, this paper presents an emergy (the amount of energy consumed in direct and indirect transformations to make a product or service) based sustainability evaluation and improvement method for machining systems, contributing to the improvement of energy efficiency, resource efficiency and environmental performance, and realizing the sustainability development. First, the driver and challenge are studied, and the scope and hypothesis of the sustainable machining system are illustrated. Then, the emergy-based conversion efficiency model is proposed, which are (1) effective emergy utilization rate (EEUR), (2) emergy efficiency of unit product (EEUP) and (3) emergy conversion efficiency (ECE), to measure and evaluate the sustainable machining system from the perspectives of energy, resource and environment. Finally, the proposed model is applied to a vehicle-bridge machining process, and the results show t... [more]
Enhancement Study of Ice Storage Performance in Circular Tank with Finned Tube
Hua Zhou, Mengting Chen, Xiaotian Han, Peng Cao, Feng Yao, Liangyu Wu
July 30, 2019 (v1)
Keywords: finned tube, ice storage, natural convection, numerical simulation, visualization experiment
Combined experimental and numerical studies are conducted to study ice storage performance of an ice storage tank with finned tube. Axially arranged fins on the refrigerant tube are applied to enhance the solidification. The evolution of the solid−liquid interface and the variation of temperature of the typical position is examined. The effect of natural convection is discussed in detail. In addition, the effects of refrigerant temperature and initial water temperature on the ice storage performance are analyzed. The results indicate that the ice storage performance is enhanced by the metal fins remarkably. The defection of poor heat transfer after ice is formed can be solved by applying fins in ice storage devices. Natural convection leads to unnecessary mixing of water with different temperatures, lessening the cooling energy stored and acting as a disadvantage during solidification. Decreasing the refrigerant temperature and initial water temperature is beneficial for ice storage.
Development of a 60 kHz, 180 kW, Over 85% Efficiency Inductive Power Transfer System for a Tram
Seung-Hwan Lee, Jae-Hee Kim, Jun-Ho Lee
July 29, 2019 (v1)
Keywords: coil design, hybrid train, inductive power transfer, on-line electric vehicle (OLEV), wireless power transfer (WPT)
Conventional contact-based train power transfer systems have high maintenance costs and safety issues and cause noise and additional aerodynamic drag. Instead of the conventional system, a loosely coupled online wireless power transfer (WPT) system for a train is proposed in this paper. The operating frequency of the proposed design is 60 kHz to ensure a low flux density and a high-efficiency system with a large air gap. In addition, a new transmitter track and pick-up geometry for 60 kHz operation are designed using finite element analysis (FEA). The proposed design is evaluated theoretically and experimentally. By using the simulated results, a new 180 kW, 15 m test-bed for a tram is constructed. The total power transfer efficiency is greater than 85% at the rated output power, and the loss distribution in the system is identified. Electromagnetic field (EMF) radiation and the voltage induction at the rail are measured for safety evaluation. The measured EMF satisfied international g... [more]
A Process for the Separation of Noble Metals from HCl Liquor Containing Gold(III), Palladium(II), Platinum(IV), Rhodium(III), and Iridium(IV) by Solvent Extraction
Wei Dong Xing, Man Seung Lee
July 28, 2019 (v1)
Keywords: gold, HCl, platinum group metals, solvent extraction
The demand for noble metals is increasing, owing to their excellent chemical and physical properties. In order to meet the demand, the recovery of noble metals with high purity from diverse secondary resources, which contain small amounts of noble metals, is of immense value. In this work, the possibility of the separation of Au(III), Pd(II), Pt(IV), Rh(III), and Ir(IV) by solvent extraction from a synthetic HCl solution is investigated. Only Au(III) was selectively extracted by Cyanex 272 in the HCl concentration range from 0.5 M to 9 M, leaving the other metal ions in the raffinate. The loaded Au(III) in Cyanex 272 was efficiently stripped by (NH2)2CS. The other four noble metals were sequentially separated on the basis of the procedures reported in the previous work. The mass balance showed that about 98% of each metal, except Pt(IV), was recovered by the proposed process. An efficient process for the recovery of the five noble metal ions from the HCl leaching solution of secondary... [more]
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