Records with Subject: Process Design
Showing records 1 to 25 of 219. [First] Page: 1 2 3 4 5 Last
Single Shooting Method for Semicontinuous Distillation Design
Pranav Bhaswanth Madabhushi, Thomas Alan Adams II
November 13, 2019 (v2)
Keywords: Boundary Value Problem, CasADi, Cyclic Steady State, Semicontinuous Distillation, Single Shooting
Ternary separation using the process of semicontinuous distillation was proposed to be carried out in a single distillation column and a process vessel, which is called the middle vessel [1]. During the process of separation, inlet and outlet material streams of the middle vessel are either operational or non-operational based on its state. With the help of these state-dependent discrete actions, periodic feed charges and the intermediate-boiling product discharges are carried out in the middle vessel, while the low and high volatile components are removed continuously from the column. This periodic process is thus modelled mathematically as a limit-cycle oscillating hybrid system [2] for design purposes. The semicontinuous distillation process design involves estimating equipment sizes, controller tuning parameters, and column design parameters which are all time-invariant parameters of the oscillating hybrid system. These system parameters are chosen to operate the process in a hydra... [more]
Study on Interfacial Surface in Modified Spray Tower
Marek Ochowiak, Sylwia Włodarczak, Ivan Pavlenko, Daniel Janecki, Andżelika Krupińska, Małgorzata Markowska
November 5, 2019 (v1)
Keywords: confusor, interfacial surface, modified spray tower, Sauter mean diameter
This paper presents an analysis of the changes in interfacial surface and the size of droplets formed in a spray tower. The interfacial surface and the size of droplets formed are of fundamental importance to the performance of the equipment, both in terms of pressure drop and process efficiency. Liquid film and droplet sizes were measured using a microphotography technique. The confusors studied were classical, with profiled inside surface, and with double profiled inside surface. The liquids studied were water and aqueous solutions of high-molecular polyacrylamide (PAA) of power-law characteristics. The ranges of process Reynolds number studied were as follows: ReG ∈ (42,700; 113,000), ReL ∈ (170; 15,200). A dimensionless correlation for reduced Sauter mean diameter is proposed.
An Investigation on the Effect of the Total Efficiency of Water and Air Used Together as a Working Fluid in the Photovoltaic Thermal Systems
Mustafa Atmaca, İmdat Zafer Pektemir
October 26, 2019 (v1)
Keywords: natural ambient conditions, solar energy, total efficiency, water based PV/T system, water- and air-based PV/T system
The temperature of a PV (photovoltaic) panel increases when it produces electricity but its electrical efficiency decreases when the temperature increases. In addition, the electrical efficiency of the PV panel is very limited. To increase the PV efficiency, the rest of the solar irradiance must be used, together with the temperature being kept at an optimum value. With this purpose, an experimental study was conducted. Firstly, two specific photovoltaic-thermal (PV/T) systems were designed. The first was the PV/T system which used only a water heat exchanger. The other one was the PV/T system that used a water and air heat exchanger. In the latter PV/T system, air passed through both the top of the PV panel and the bottom of it while water passed through only the bottom of the panel in a separate heat exchanger. In this way, the water and air absorbed the thermal energy of the panel by means of separate heat exchangers, simultaneously. In addition to the two systems mentioned above, a... [more]
Robust Process Design in Pharmaceutical Manufacturing under Batch-to-Batch Variation
Xiangzhong Xie, René Schenkendorf
October 26, 2019 (v1)
Keywords: batch-to-batch variation, freeze-drying, parametric probability-box, pharmaceutical manufacturing, point estimate method, robust process design
Model-based concepts have been proven to be beneficial in pharmaceutical manufacturing, thus contributing to low costs and high quality standards. However, model parameters are derived from imperfect, noisy measurement data, which result in uncertain parameter estimates and sub-optimal process design concepts. In the last two decades, various methods have been proposed for dealing with parameter uncertainties in model-based process design. Most concepts for robustification, however, ignore the batch-to-batch variations that are common in pharmaceutical manufacturing processes. In this work, a probability-box robust process design concept is proposed. Batch-to-batch variations were considered to be imprecise parameter uncertainties, and modeled as probability-boxes accordingly. The point estimate method was combined with the back-off approach for efficient uncertainty propagation and robust process design. The novel robustification concept was applied to a freeze-drying process. Optimal... [more]
A Review of the Chemistry of Anaerobic Digestion: Methods of Accelerating and Optimizing Process Efficiency
Anthony Anukam, Ali Mohammadi, Muhammad Naqvi, Karin Granström
October 26, 2019 (v1)
Keywords: anaerobic digestion, feedstock, methane yield, process chemistry, syntrophic interaction
The anaerobic digestion technology has been in existence for centuries and its underlying theory established for decades. It is considered a useful technology for the generation of renewable energy, and provides means to alleviate problems associated with low access to energy. However, a great deal of current research is targeted towards the optimization of this technology under diverse digestion process conditions. This review presents an in-depth analysis of the chemistry of anaerobic digestion and discusses how process chemistry can be used to optimize system performance through identification of methods that can accelerate syntrophic interactions of different microorganisms for improved methanogenic reactions. Recent advances in addition to old research are discussed in order to offer a general but comprehensive synopsis of accumulated knowledge in the theory of anaerobic digestion, as well as an overview of previous research and future directions and opportunities of the AD techno... [more]
Technoeconomic Evaluation of a Process Capturing CO2 Directly from Air
Romesh Pramodya Wijesiri, Gregory Paul Knowles, Hasina Yeasmin, Andrew Forbes Alexander Hoadley, Alan Loyd Chaffee
October 26, 2019 (v1)
Keywords: Adsorption, Carbon Capture, cost, direct air capture, economic, model, polyethyleneimine, steam, temperature vacuum swing
Capturing CO2 directly from air is one of the options for mitigating the effects global climate change, and therefore determining its cost is of great interest. A process model was proposed and validated using laboratory results for adsorption/desorption of CO2, with a branched polyethyleneimine (PEI) loaded mesocellular foam (MCF) silica sorbent. The model was subjected to a Multi-Objective Optimization (MOO) to evaluate the technoeconomic feasibility of the process and to identify the operating conditions which yielded the lowest cost. The objectives of the MOO were to minimize the cost of CO2 capture based on a discounted cash flow analysis, while simultaneously maximizing the quantity of CO2 captured. This optimization identified the minimum cost of capture as 612 USD tonne−1 for dry air entering the process at 25 °C, and 657 USD tonne−1 for air at 22 °C and 39% relative humidity. The latter represents more realistic conditions which can be expected for subtropical climates. The co... [more]
Improving Coal Flotation by Gaseous Collector Pretreatment Method and its Potential Application in Preparing Coal Water Slurry
Liang Shen, Fanfei Min, Lingyun Liu, Changguo Xue, Jinbo Zhu
October 26, 2019 (v1)
Keywords: coal water slurry, flotation, gaseous pretreatment, low-rank coal
Low-rank coal is difficult to upgrade using conventional flotation methods due to its high hydrophilic properties. Thus, it is necessary to explore new methods for upgrading and utilizing low-rank coal. In this investigation, a gaseous dodecane pretreatment method was used to enhance the flotation performance of low-rank coal. Pore distribution analysis, FTIR (Fourier Transform Infrared Spectroscopy), and contact angle measurements were used to study the surface properties of the coal sample. Size distribution and float-sink test results indicated that the coal sample contained a lot of clean coal with low ash content, which could be used as a high quality raw material for making coal water slurry. FTIR, pore distribution analysis, and contact angle results showed that the coal was very hydrophilic due to the high concentration of -OH group and the large number of pores and cracks on the coal surface. The hydrophobicity of the coal sample was significantly improved by the gaseous dodec... [more]
Optimal Design of a Distillation System for the Flexible Polygeneration of Dimethyl Ether and Methanol Under Uncertainty
Thomas A Adams II, Tokiso Thatho, Matthew C Le Feuvre, Christopher LE Swartz
October 22, 2019 (v2)
Keywords: Dimethyl Ether, Distillation, Flexible polygeneration, Methanol, Optimization, Polygeneration, Process Design Under Uncertainty
This presentation concerns the promising new area of flexible polygeneration, a chemical process design concept in which a chemical plant is able to change its product outputs throughout its lifetime in response to changing market conditions, business objectives, or other external factors. In this talk we present a new flexible polygeneration process system that can switch between dimethyl ether (DME) or methanol production, depending on need. Classic flexible polygeneration systems typically utilize separate process trains for each product, in which whole process trains are turned on or off (or up or down) depending on the current product. However, our proposed process combines the two process trains into one, in which most of the process equipment is always used during either mode of production, but with different operating conditions. In this work, we show how this significantly reduces capital expenditure, reduces the plant footprint, and ultimately is more economical than a tradit... [more]
Economic Viability and Environmental Efficiency Analysis of Hydrogen Production Processes for the Decarbonization of Energy Systems
Li Xu, Ying Wang, Syed Ahsan Ali Shah, Hashim Zameer, Yasir Ahmed Solangi, Gordhan Das Walasai, Zafar Ali Siyal
September 30, 2019 (v1)
Keywords: economic viability, environmental efficiency, hydrogen production processes, multi-criteria analysis, Renewable and Sustainable Energy
The widespread penetration of hydrogen in mainstream energy systems requires hydrogen production processes to be economically competent and environmentally efficient. Hydrogen, if produced efficiently, can play a pivotal role in decarbonizing the global energy systems. Therefore, this study develops a framework which evaluates hydrogen production processes and quantifies deficiencies for improvement. The framework integrates slack-based data envelopment analysis (DEA), with fuzzy analytical hierarchy process (FAHP) and fuzzy technique for order of preference by similarity to ideal solution (FTOPSIS). The proposed framework is applied to prioritize the most efficient and sustainable hydrogen production in Pakistan. Eleven hydrogen production alternatives were analyzed under five criteria, including capital cost, feedstock cost, O&M cost, hydrogen production, and CO2 emission. FAHP obtained the initial weights of criteria while FTOPSIS determined the ultimate weights of criteria for each... [more]
Overview of Alternative Ethanol Removal Techniques for Enhancing Bioethanol Recovery from Fermentation Broth
Hamid Zentou, Zurina Zainal Abidin, Robiah Yunus, Dayang Radiah Awang Biak, Danil Korelskiy
September 23, 2019 (v1)
Keywords: Adsorption, bioethanol, Extraction, pervaporation, separation, stripping, unconventional, vacuum
This study aims at reviewing the alternative techniques for bioethanol recovery, highlighting its advantages and disadvantages, and to investigate the technical challenges facing these alternatives to be widely used. The findings showed that the integration of these techniques with the fermentation process did not meet a large acceptance in the industrial sector. The majority of conducted studies were mainly focusing on ethanol recovery from aqueous standard solution rather than the investigation of these techniques performance in fermentation-separation coupled system. In this context, pervaporation has received more attention as a promising alternative to distillation. However, some challenges are facing the integration of these techniques in the industrial scale as the fouling problem in pervaporation, the toxicity of solvent in liquid extraction, energy consumption in vacuum fermentation. It was also found that there is a lack of the technical economic analysis for these techniques... [more]
Method of Desulfurization Process Selection Based on Improved Fuzzy Comprehensive Evaluation: A Case Study of Papermaking Desulfurization in China
Zhiguo Wang, Fei Wang, Yali Zhu, Bengang Gong
September 23, 2019 (v1)
Keywords: combination weight, entropy weight method, improved fuzzy comprehensive evaluation method (IFCE), selection of desulfurization process
With the increasingly prominent global energy and environmental problems, more and more enterprises have been required to desulfurize the exhausted gases. Different enterprises have different demands for the desulfurization process, thus the choice of desulfurization process methods has become a focus of attention. Since the evaluation of the desulfurization process involves many factors, this paper proposes an improved fuzzy comprehensive evaluation method to evaluate the selection of desulfurization process when the traditional evaluation method is not applicable. Firstly, an evaluation system with two rating indicators was constructed, which considers the subjective and objective weights comprehensively. Secondly using the two hierarchical indicators, an effective desulfurization process method was obtained according to the principle of maximum membership degree. Finally, we took a real papermaking factory as an example to illustrate the detailed implementation processes of this met... [more]
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]
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