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Records with Subject: Process Design
Showing records 1 to 25 of 467. [First] Page: 1 2 3 4 5 Last
Integration of Gasification and Solid Oxide Fuel Cells (SOFCs) for Combined Heat and Power (CHP)
Paula Costa, Filomena Pinto, Rui Neto André, Paula Marques
October 25, 2022 (v1)
Keywords: gasification, solid oxide fuel cells (SOFC), syngas conditioning
This paper reviews the most recent information about the main operations to produce energy from carbonaceous materials, namely biomass and wastes through the integration of gasification, syngas cleaning and solid oxide fuel cells (SOFCs), which have shown to be a good option for combined heat and power (CHP) production, due to high efficiency and low environmental impact. However, some challenges still need to be overcome, mainly when mixed feedstocks with high contents of hazardous contaminants are used, thus syngas cleaning and conditioning is of major importance. Another drawback is SOFC operation, hence new materials especially for the anode has been proposed and tested. An overall process to produce CHP by gasification integration with SOFC is proposed.
Design, Modelling, and Experimental Validation of a Scalable Continuous-Flow Hydrothermal Liquefaction Pilot Plant
Ib Johannsen, Björn Kilsgaard, Viktor Milkevych, Dale Moore
October 13, 2022 (v1)
Keywords: biofuel, chemical process engineering, heat transfer, Hydrothermal Liquefaction, non-isothermal fluid flow, pilot plant, plug flow reactor, process modelling, sustainable fuel
In this study, the design and practical implementation of a novel, scalable plug-flow pilot plant for hydrothermal liquefaction of organic feedstock is presented. The overall discussion comprises the system’s design, process modelling, and simulation, as well as results for an experimental validation of the proposed design with a focus on fluid dynamics and heat transfer. The design criteria take into account the scalability of the plug-flow processing system, optimized non-isothermal flow conditions of highly viscous liquids in a tubular system at harsh process conditions, specifically high pressure and medium temperatures, and overall maintenance suitability. A novel forced flow oscillation system as well as unique heat exchange design to reduce the energy consumption during system operation, maximize local flow mixing, and minimize plugging are proposed and experimentally tested. To achieve a better understanding and optimization of Hydrothermal Liquefaction (HTL) (and other) proces... [more]
Conceptual Design of a Negative Emissions Polygeneration Plant for Multiperiod Operations Using P-Graph
Jean Pimentel, Ákos Orosz, Kathleen B. Aviso, Raymond R. Tan, Ferenc Friedler
October 13, 2022 (v1)
Keywords: carbon dioxide removal, multiperiod optimization, negative emissions technologies, power-to-x, process network synthesis
Reduction of CO2 emissions from industrial facilities is of utmost importance for sustainable development. Novel process systems with the capability to remove CO2 will be useful for carbon management in the future. It is well-known that major determinants of performance in process systems are established during the design stage. Thus, it is important to employ a systematic tool for process synthesis. This work approaches the design of polygeneration plants with negative emission technologies (NETs) by means of the graph-theoretic approach known as the P-graph framework. As a case study, a polygeneration plant is synthesized for multiperiod operations. Optimal and alternative near-optimal designs in terms of profit are identified, and the influence of network structure on CO2 emissions is assessed for five scenarios. The integration of NETs is considered during synthesis to further reduce carbon footprint. For the scenario without constraint on CO2 emissions, 200 structures with profit... [more]
Energy, Exergy, and Thermo-Economic Analysis of Renewable Energy-Driven Polygeneration Systems for Sustainable Desalination
Mohammad Hasan Khoshgoftar Manesh, Viviani Caroline Onishi
October 12, 2022 (v1)
Keywords: economic analysis, energy and exergy analysis, exergoeconomic analysis, exergoenvironmental analysis, Renewable and Sustainable Energy, sustainable development
Reliable production of freshwater and energy is vital for tackling two of the most critical issues the world is facing today: climate change and sustainable development. In this light, a comprehensive review is performed on the foremost renewable energy-driven polygeneration systems for freshwater production using thermal and membrane desalination. Thus, this review is designed to outline the latest developments on integrated polygeneration and desalination systems based on multi-stage flash (MSF), multi-effect distillation (MED), humidification-dehumidification (HDH), and reverse osmosis (RO) technologies. Special attention is paid to innovative approaches for modelling, design, simulation, and optimization to improve energy, exergy, and thermo-economic performance of decentralized polygeneration plants accounting for electricity, space heating and cooling, domestic hot water, and freshwater production, among others. Different integrated renewable energy-driven polygeneration and desa... [more]
Comparative Investigation of Different CO2 Capture Technologies for Coal to Ethylene Glycol Process
Yanqing Ma, Yitao Liao, Yi Su, Baojie Wang, Yong Yang, Dong Ji, Hongwei Li, Huairong Zhou, Dongliang Wang
October 12, 2022 (v1)
Keywords: acid gas removal, Carbon Dioxide Capture, coal to ethylene glycol, performance analysis, process simulation
The coal to ethylene glycol (CTEG) process has drawn much attention due to the serious conflict between supply and demand of ethylene glycol in China. However, it is inevitably accompanied by the problem of high CO2 emissions. Carbon capture is one of the most promising potential effective ways to address this issue. However, the CTEG process, integrated with carbon capture technology, will lead to energy and economic penalties. Thus, a comprehensive evaluation of CTEG process with different CO2 capture technologies is urgently needed. This study analyzed the technoeconomic performance of four CO2 capture alternatives for the CTEG process: Rectisol, mono-ethanol amine (MEA), chilled ammonia process (CAP) and dimethyl carbonate (DMC) technologies. Results show the energy consumption of CO2 capture of the Rectisol process is the lowest, 1.88 GJ/tCO2, followed by the DMC process, 2.10 GJ/tCO2, the CAP process, 3.64 GJ/tCO2, and the MEA process, 5.20 GJ/tCO2. The CO2 capture cost of the Re... [more]
Advanced Bioethanol Production: From Novel Raw Materials to Integrated Biorefineries
Aleta Duque, Cristina Álvarez, Pablo Doménech, Paloma Manzanares, Antonio D. Moreno
October 12, 2022 (v1)
Keywords: bio-based products, biochemical route, Biofuels, biomass fractionation
The production of so-called advanced bioethanol offers several advantages compared to traditional bioethanol production processes in terms of sustainability criteria. This includes, for instance, the use of nonfood crops or residual biomass as raw material and a higher potential for reducing greenhouse gas emissions. The present review focuses on the recent progress related to the production of advanced bioethanol, (i) highlighting current results from using novel biomass sources such as the organic fraction of municipal solid waste and certain industrial residues (e.g., residues from the paper, food, and beverage industries); (ii) describing new developments in pretreatment technologies for the fractionation and conversion of lignocellulosic biomass, such as the bioextrusion process or the use of novel ionic liquids; (iii) listing the use of new enzyme catalysts and microbial strains during saccharification and fermentation processes. Furthermore, the most promising biorefinery approa... [more]
Stabilization of Anaerobic Co-Digestion Process via Constant the Digestate Solids Content
Risu Na, Keisuke Uchitani, Kazuto Yoshida, Naoto Shimizu
October 12, 2022 (v1)
Keywords: anaerobic digestion, biogas, mass balance, solid content, specific methane yield
The process instability of anaerobic digestion (AD) is a common issue and may result in underperformance or short-term process failure. Extensive research has shown that total solids (TS) content in AD has a significant impact on system stability and performance. However, no study has examined the feasibility of stabilizing the AD process by maintaining constant TS content in the digestate. In this study, an innovative control approach based on constant TS content in the digestate during AD was developed using a mass balance equation. Two levels of TS content (desired values of 4% wet basis (w.b.) and 6% w.b.) were compared with conventional control. The process stability was examined by monitoring digestate components and pH. Substrate-specific methane yield (m3 CH4/kg VS) was used to assess the effectiveness of the controlled conditions. The results showed that the digestate TS content during AD can be controlled and that the digestion process can be stabilized by controlled conditio... [more]
Biodiesel Dry Purification Using Unconventional Bioadsorbents
Emilio Arenas, Stephanie M. Villafán-Cáceres, Yetzin Rodríguez-Mejía, Jonathan A. García-Loyola, Omar Masera, Georgina Sandoval
October 12, 2022 (v1)
Keywords: bioadsorbents, biodiesel, purification, waste cooking oil
The dry washing method is an alternative to replace water washing, thereby reducing the negative impacts of contamination. However, commercial adsorbents come from industrial processes that, due to their composition, may not be such a sustainable resource in the global biodiesel production process. In this study, the use of organic residues, such as sawdust, coconut fiber, nutshell, rice husk, and water hyacinth fiber, were proposed as bioadsorbents for the purification of biodiesel from waste cooking oil. Quality parameters such as the acid number, water content, and free and total glycerin content were evaluated and compared with those after purification with commercial adsorbents (Magnesol and Amberlite BD10DRY). Promising results were obtained using sawdust in the purification process, achieving a reduction in the acid number value of 31.3% respect to the unpurified biodiesel. Indeed, the reduction with sawdust was more efficient than with Amberlite BD10DRY (that increased the acid... [more]
Mesophilic Anaerobic Digestion of Hydrothermally Pretreated Lignocellulosic Biomass (Norway Spruce (Picea abies))
Nirmal Ghimire, Rune Bakke, Wenche Hennie Bergland
October 12, 2022 (v1)
Keywords: hot water extraction, hydrolysate, lignocellulosic biomass, mesophilic anaerobic digestion, Norway spruce
Hot water extraction (HWE) removes hemicellulose from woody biomass to give improved end products while producing a sugar-rich by-product stream, which requires proper treatment before disposal. Hot water extracted Norway spruce (Picea abies) at two different pretreatment conditions (140 °C for 300 min (H140) and 170 °C for 90 min (H170)) generated hydrolysate as a by-product, which was used in mesophilic anaerobic digestion (AD) as substrate. H140 gave a higher methane yield (210 NmL/g COD—chemical oxygen demand) than H170 (148 NmL/g COD) despite having a lower concentration of sugars, suggesting that different levels of inhibitors (furans and soluble lignin) and recalcitrant compounds (soluble lignin) affected the methane yield significantly. Organic loads (OLs) had a negative effect on the methane yield, as observed during AD of H170, while such an effect was not observed in the case of H140. This suggests that the decrease in methane yield (32%) of H170 compared to H140 is primaril... [more]
Comparative Life Cycle Assessment of Co-Processing of Bio-Oil and Vacuum Gas Oil in an Existing Refinery
Meirong Shi, Xin Zhao, Qi Wang, Le Wu
October 12, 2022 (v1)
Keywords: bio-oil, co-processing, Eco-indicator 99, FCC, LCA, vacuum gas oil
The co-cracking of vacuum gas oil (VGO) and bio-oil has been proposed to add renewable carbon into the co-processing products. However, the environmental performance of the co-processing scheme is still unclear. In this paper, the environmental impacts of the co-processing scheme are calculated by the end-point method Eco-indicator 99 based on the data from actual industrial operations and reports. Three scenarios, namely fast pyrolysis scenario, catalytic pyrolysis scenario and pure VGO scenario, for two cases with different FCC capacities and bio-oil co-processing ratios are proposed to present a comprehensive comparison on the environmental impacts of the co-processing scheme. In Case 1, the total environmental impact for the fast pyrolysis scenario is 1.14% less than that for the catalytic pyrolysis scenario while it is only 26.1% of the total impacts of the pure VGO scenario. In Case 2, the environmental impact of the fast pyrolysis scenario is 0.07% more than that of the catalyti... [more]
Exploration of a Molecularly Imprinted Polymer (MIPs) as an Adsorbent for the Enrichment of Trenbolone in Water
Anele Mpupa, Mehmet Dinc, Boris Mizaikoff, Philiswa Nosizo Nomngongo
October 12, 2022 (v1)
Keywords: androgenic hormones, endocrine disruptors, molecularly imprinted polymers, solid-phase extraction, trenbolone
The presence of endocrine disruptors in surface waters can have negative implications on wildlife and humans both directly and indirectly. A molecularly imprinted polymer (MIP) was explored for its potential to enhance the UV-Vis determination of trenbolone in water using solid-phase extraction (SPE). The synthesized MIP was studied using Fourier transform infrared spectra (FTIR) and scanning electron microscopy (SEM). Using the MIP resulted in a preconcentration and enrichment factor of 14 and 8, respectively. Trenbolone binding on the MIP was shown to follow a Langmuir adsorption and had a maximum adsorption capacity of 27.5 mg g−1. Interference studies showed that the MIP selectivity was not compromised by interferences in the sample. The MIP could be recycled three times before significant loss in analyte recovery.
Novel approach for low CO2 intensity hydrogen from natural gas
Julian Straus, Vidar T. Skjervold, Rahul Anantharaman, David Berstad
September 20, 2022 (v1)
Keywords: Carbon Dioxide Capture, Hydrogen production, Low emission H2, Process integration
Hydrogen from natural gas with CO2 capture can be a key transition technology to a low carbon energy system due to the abundance of natural gas and the possibility to increase the production capacity quickly. However, it is necessary to achieve both a high energy efficiency and a high CO2 capture ratio to be a viable option. The liquefaction of CO2 is one promising separation technology as it provides the captured CO2 in a transportable format. This paper therefore proposes a hydrogen production process with integrated CO2 liquefaction. Efficiencies of up to 84.7 % (Based on the higher heating value) and CO2 capture ratios of up to 97.2 % can be achieved. One advantage of the utilization of CO2 liquefaction as separation technology is furthermore the possibility to incorporate a partial recycle of the flue gas from the separation to the water–gas shift reaction, increasing both energy efficiency and carbon capture ratio.
Optimisation of the Geometric Parameters of Longitudinally Finned Air Cooler Tubes Operating in Mixed Convection Conditions
Piotr Kopeć, Beata Niezgoda-Żelasko
January 24, 2022 (v1)
Keywords: heat pump evaporator, longitudinal finned tubes, mixed convection, optimisation of geometric parameters
The results of optimisation calculations presented in the article are related to longitudinally finned tubes of a heat pump evaporator operating under natural wind-induced flow of outdoor air conditions. The finned surface is characterised by an unusual, wavy fin shape. The article presents the methodology applied to seeking optimal geometric parameters of the finned tube in which thermal calculations were performed by modelling a mixed convection process on the finned surface using the finite volume method. In the case of maximising the heat flow with the minimum mass of the fins, the optimal solution was dominated by the minimum mass of the fins and thus geometric parameters correspond to the number of fins n = 6, fin height h = 0.065 and fin thickness s = 0.0015 m. Optimisation calculations made for maximum efficiency of the exchanger at constant mass indicated that the tube with ten fins (n = 10) with a height of h = 0.11 m and a thickness of s = 0.0018 m allowed maximum heat flow... [more]
Valorization of Biomass Pyrolysis By-Products for Heat Production in the Ontario Steel Industry: A Techno-Economic Analysis
Jamie Rose, Thomas A. Adams II
November 5, 2021 (v1)
As part of efforts to reduce carbon emissions in the iron and steel industry, which are especially pertinent in Canada due to rising carbon taxes, Canadian producers have been investigating the effects of replacing coal used in pulverized coal injection with biochar. Although there has been research into the economic value and effect on net life cycle emissions of using the biochar product itself, there are no comprehensive techno-economic analyses which investigate the value and potential uses of the by-products of biomass pyrolysis. These by-products include volatile organic compounds, known collectively as tar or bio-oil, and light gases, which are mainly hydrogen, carbon monoxide, carbon dioxide, and methane. Since only 20-30% of the mass of pyrolyzed biomass is actually converted to char, with the rest converted to the by-products, [1] usage of these by-products is likely the key to increasing the value of biochar to a degree that makes up for the market price of biochar currently... [more]
Optimization under uncertainty of a hybrid waste tire and natural gas feedstock flexible polygeneration system using a decomposition algorithm
Avinash Subramanian, Rohit Kannan, Flemming Holtorf, Thomas A. Adams II, Truls Gundersen, Paul I. Barton
April 5, 2022 (v2)
Keywords: Decomposition Algorithm, Optimization under uncertainty, Polygeneration system, Stochastic Programming, Waste Tire, Waste-to-Energy
Market uncertainties motivate the development of flexible polygeneration systems that are able to adjust operating conditions to favor production of the most profitable product portfolio. However, this operational flexibility comes at the cost of higher capital expenditure. A scenario-based two-stage stochastic nonconvex Mixed-Integer Nonlinear Programming (MINLP) approach lends itself naturally to optimizing these trade-offs. This work studies the optimal design and operation under uncertainty of a hybrid feedstock flexible polygeneration system producing electricity, methanol, dimethyl ether, olefins or liquefied (synthetic) natural gas. The recently developed GOSSIP software framework is used for modeling the optimization problem as well as its efficient solution using the Nonconvex Generalized Benders Decomposition (NGBD) algorithm. Two different cases are studied: The first uses estimates of the means and variances of the uncertain parameters from historical data, whereas the seco... [more]
Purification Methods for Captured CO2 from Petroleum Coke Oxy-Combustion Power Plants
Tia Ghantous, Ikenna J Okeke, Thomas A Adams II
October 21, 2021 (v2)
Keywords: Carbon Dioxide Capture, eco-technoeconomic analysis, oxy-combustion, Petroleum Coke
We present eco-technoeconomic analyses of four processes, including two novel designs, for the purification of captured CO2 from flue gas for a petroleum coke (petcoke) oxy-combustion power plant operated with carbon capture and sequestration (CCS). A base case petcoke oxy-combustion design obtained from a previous study consisting of flue gas water removal using condensation was used in this study. Other purification processes evaluated consist of a cryogenic distillation petcoke oxy-combustion with CCS, an oxygen deficient petcoke oxy-combustion with CCS and a catalytic dehydration petcoke oxy-combustion via hydrogen conversion with CCS. An eco-technoeconomic analysis considering greenhouse gas (GHG) emissions, levelized cost of electricity (LCOE), thermal efficiency and CO2 product purity to meet pipe-line specifications, was conducted on all purification candidates. This revealed that base case design did not meet the CO2 pipeline specifications. The highest LCOE was attributed to... [more]
Research on Optimization of Coal Slime Fluidized Bed Boiler Desulfurization Cooperative Operation
Yangjian Xiao, Yudong Xia, Aipeng Jiang, Xiaofang Lv, Yamei Lin, Hanyu Zhang
October 14, 2021 (v1)
Keywords: boiler thermal efficiency, cooperative optimization, mechanism model, Simulation, slime fluidized bed
The semi-dry desulfurization of slime fluidized bed boilers (FBB) has been widely used due to its advantages of low cost and high desulfurization efficiency. In this paper, the cooperative optimization of a two-stage desulfurization processes in the slime fluidized bed boiler was studied, and a model-based optimization strategy was proposed to minimize the operational cost of the desulfurization system. Firstly, a mathematical model for the FBB with a two-stage desulfurization process was established. The influences of coal slime elements on combustion flue gas and the factors that may affect the thermal efficiency of the boiler were then analyzed. Then, on the basis of the developed model, a number of parameters affecting the SO2 concentration at the outlet of the slime fluidized bed boiler were simulated and deeply analyzed. In addition, the effects of the sulfur content of coal slime, excess air coefficient, and calcium to sulfur ratio were also discussed. Finally, according to the... [more]
Analysis and Optimization of Two Film-Coated Tablet Production Processes by Computer Simulation: A Case Study
Stefanie Hering, Nico Schäuble, Thomas M. Buck, Brigitta Loretz, Thomas Rillmann, Frank Stieneker, Claus-Michael Lehr
October 14, 2021 (v1)
Keywords: 3D simulation modeling and analysis, bottleneck analysis, model implementation, production costs, resource conservation
Increasing regulatory demands are forcing the pharmaceutical industry to invest its available resources carefully. This is especially challenging for small- and middle-sized companies. Computer simulation software like FlexSim allows one to explore variations in production processes without the need to interrupt the running process. Here, we applied a discrete-event simulation to two approved film-coated tablet production processes. The simulations were performed with FlexSim (FlexSim Deutschland—Ingenieurbüro für Simulationsdienstleistung Ralf Gruber, Kirchlengern, Germany). Process visualization was done using Cmap Tools (Florida Institute for Human and Machine Cognition, Pensacola, FL, USA), and statistical analysis used MiniTab® (Minitab GmbH, Munich, Germany). The most critical elements identified during model building were the model logic, operating schedule, and processing times. These factors were graphically and statistically verified. To optimize the utilization of employees,... [more]
Integration of a Combined Cycle Power Plant with MED-RO Desalination Based on Conventional and Advanced Exergy, Exergoeconomic, and Exergoenvironmental Analyses
Mohammad Hasan Khoshgoftar Manesh, Reza Shojaei Ghadikolaei, Hossein Vazini Modabber, Viviani Caroline Onishi
October 11, 2021 (v1)
Keywords: advanced exergy analysis, combined cycle power plant (CCPP), desalination, exergoeconomic analysis, exergoenvironmental analysis, mathematical modelling and simulation, multi-effect distillation (MED), reverse osmosis (RO), water and power production
The ever-increasing world population, change in lifestyle, and limited natural water and energy resources have made industrial seawater desalination plants the leading contenders for cost-efficient freshwater production. In this study, the integration of a combined cycle power plant (CCPP) with multi-effect distillation (MED) and reverse osmosis (RO) desalination units is investigated through comprehensive conventional and advanced exergy, exergoeconomic, and exergoenvironmental analyses. Firstly, the thermodynamic modelling of the CCPP is performed by using a mathematical programming procedure. Then, a mathematical model is developed for the integration of the existing CCPP plant with MED and RO desalination units. Finally, conventional and advanced exergy, exergoeconomic, and exergoenvironmental analyses are carried out to assess the main performance parameters of the integrated CCPP and MED-RO desalination system, as well as to identify potential technical, economic, and environment... [more]
Modeling and Flowsheet Simulation of Vibrated Fluidized Bed Dryers
Soeren E. Lehmann, Moritz Buchholz, Alfred Jongsma, Fredrik Innings, Stefan Heinrich
October 11, 2021 (v1)
Keywords: drying kinetics, Dyssol, flowsheet simulation, fluidized bed drying, Modelling, vibrated fluidized bed
Drying in fluidized beds is an important step in the production of powdered materials. Especially in the food and pharmaceutical industry, fluidized bed dryers are often vibrated to improve the drying process. In the current work, a continuous fluidized bed drying model is implemented in the novel, open-source flowsheet simulation framework Dyssol. The new model accounts for the hydrodynamic characteristics of all Geldart groups as well as the impact of mechanical vibration on the drying process. Distributed particle properties are considered by the model. Comprehensive validation of the model was conducted for a wide range of process parameters, different materials, dryer geometries and dimensions as well as the impact of vibration. Particle properties are predicted accurately and represent the broad experimental data well. A sensitivity analysis of the model confirmed grid independence and the validity of underlying model assumptions.
Solubility Data of Potential Salts in the MgO-CaO-SO2-H2O-O2 System for Process Modeling
Barbara D. Weiß, Michael Harasek
September 22, 2021 (v1)
Keywords: hydroxides, magnesium hydroxide slurry, precipitation, SO2 absorption, solid-liquid phase equilibria, sulfates, sulfites
This review studies unwanted precipitation reactions, which can occur in SO2 absorption processes using a magnesium hydroxide slurry. Solubility data of potential salts in the MgO-CaO-SO2-H2O system are evaluated. The reviewed data can serve as a reliable basis for process modeling of this system used to support the optimization of the SO2 absorption process. This study includes the solubility data of MgSO3, MgSO4, Mg(OH)2, CaSO3, CaSO4, and Ca(OH)2 as potential salts. The solubility is strongly dependent on the state of the precipitated salts. Therefore, this review includes studies on the stability of different forms of the salts under different conditions. The solubility data in water over temperature serve as a base for modeling the precipitation in such system. Furthermore, influencing factors such as pH value, SO2 content and the co-existence of other salts are included and available data on such dependencies are reviewed. Literature data evaluated by the International Union of P... [more]
Experimental and Numerical Analysis of a Low Environmental Impact Pyro-Gasification System for the Energetic Valorization of Waste through a Biomass Steam Power Plant
Alfredo Gimelli, Massimiliano Muccillo, Raniero Sannino, Giacobbe Braccio, Vincenzo Capone, Giacinto Cornacchia, Matteo Manganiello, Carmine Mongiello, Vinod Kumar Sharma
September 22, 2021 (v1)
Keywords: biomass steam power plant, decision-making process, multi-objective optimization problem, pyro-gasification plant, thermochemical modeling
This paper addresses the study of a pyro-gasification plant designed, built, and operated to recover inert metals from different types of solid waste. Experimental tests were carried out using pulper as the solid waste. However, while a reliable composition analysis of the produced syngas was carried out, a precise composition evaluation of the pulper used during the experimental activities was not performed and the related data were characterized by unacceptable uncertainty. Therefore, with the aim of reliably characterizing the plant operation, a thermochemical model of the gasification process was setup to simulate the equilibrium operation of the plant and a vector optimization methodology was used to calibrate the numerical model. Then, a decision-making problem was solved to identify the most suitable optimal solution between those belonging to the Pareto optimal front, thus obtaining reliable composition data for the adopted pulper waste. In particular, four different identifica... [more]
An Integrated Approach to the Design of Centralized and Decentralized Biorefineries with Environmental, Safety, and Economic Objectives
Antioco López-Molina, Debalina Sengupta, Claire Shi, Eman Aldamigh, Maha Alandejani, Mahmoud M. El-Halwagi
July 29, 2021 (v1)
Keywords: biorefining, CAPEX correlation, centralized facilities, distributed manufacturing, integration, sustainable design
Biorefineries provide economic, environmental, and social benefits towards sustainable development. Because of the relatively small size of typical biorefineries compared to oil and gas processes, it is necessary to evaluate the options of decentralized (or distributed) plants that are constructed near the biomass resources and product markets versus centralized (or consolidated) facilities that collect biomass from different regions and distribute the products to the markets, benefiting from the economy of scale but suffering from the additional transportation costs. The problem is further compounded when, in addition to the economic factors, environmental and safety aspects are considered. This work presents an integrated approach to the design of biorefining facilities while considering the centralized and decentralized options and the economic, environmental, and safety objectives. A superstructure representation is constructed to embed the various options of interest. A mathematic... [more]
A Review of Process Systems Engineering (PSE) Tools for the Design of Ionic Liquids and Integrated Biorefineries
Nishanth G. Chemmangattuvalappil, Denny K. S. Ng, Lik Yin Ng, Jecksin Ooi, Jia Wen Chong, Mario R. Eden
July 29, 2021 (v1)
Keywords: integrated biorefineries, ionic liquids, molecular design, process optimization, process systems engineering
In this review paper, a brief overview of the increasing applicability of Process Systems Engineering (PSE) tools in two research areas, which are the design of ionic liquids and the design of integrated biorefineries, is presented. The development and advances of novel computational tools and optimization approaches in recent years have enabled these applications with practical results. A general introduction to ionic liquids and their various applications is presented followed by the major challenges in the design of optimal ionic liquids. Significant improvements in computational efficiency have made it possible to provide more reliable data for optimal system design, minimize the production cost of ionic liquids, and reduce the environmental impact caused by such solvents. Hence, the development of novel computational tools and optimization tools that contribute to the design of ionic liquids have been reviewed in detail. A detailed review of the recent developments in PSE applicat... [more]
New Design of the Reversible Jet Fan
Miroslav H. Benišek, Đorđe S. Čantrak, Dejan B. Ilić, Novica Z. Janković
July 29, 2021 (v1)
Keywords: axial fan, design, energy characteristics, jet, reversible, thrust
This paper presents two designs of the axial reversible jet fan, with the special focus on the impeller. The intention was to develop a reversible axial jet fan which operates in the same way in both rotating directions while generating thrust as high as possible. The jet fan model with the outer diameter 499.2 ± 0.1 mm and ten adjustable blades is the same, while it is in-built in two different casings. The first construction is a cylindrical casing, while the second one is profiled as a nozzle. Thrust, volume flow rate, consumed power and ambient conditions were measured after the international standard ISO 13350. Results for both constructions are presented for three impeller blade angles: 28°, 31° and 35°, and rotation speed in the interval n = 400 to 2600 rpm. The smallest differences in thrust, depending on the fan rotation direction, as well as the highest thrust are achieved for the first design with the cylindrical casing and blade angle at the outer diameter of 35°. Therefore... [more]
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