Literature

This page lists published scientific and/or technical papers/articles that use or cite DWSIM to some extent.

Technical Papers

Evaluation of an Open-source Chemical Process Simulator Using a Plant-wide Oil and Gas Separation Plant Flowsheet Model as Basis

Author: Anders Andreasen

Abstract: In this paper, a detailed evaluation of the open source process simulator DWSIM is presented. Using a previously published simulation model of an oil and gas separation plant, the results obtained with DWSIM are compared to a commercial process simulator widely used in the industry. The modelled flow scheme comprises a vast number of unit operations including separators (flash vessels), valves, splitters, mixers, compressors, heat exchangers, pumps and recycles (tear streams). The results obtained with DWSIM both for characterization of the inlet fluid as well as for a single operating state for the entire process, compare very well with the data obtained using a commercial tool. A rigorous comparison is made and generally, compared results are within 1% in deviation with a few exceptions. Further, an elaborate comparison is made for over 90 simulations with different settings where 10 independent variables are randomly varied over a wide range. Again, good agreement is found between the two tools. The results are very encouraging and provide fidelity in the use of the investigated open source process simulation tools in a professional environment.

Download Link: https://pp.bme.hu/ch/article/view/19678

Modeling of chemical processes using commercial and open-source software: A comparison between Aspen Plus and DWSIM

Authors: Kwanchanok Tangsriwong, Puttida Lapchit, Tanatip Kittijungjit, Thepparat Klamrassamee, Yanin Sukjai1 and Yossapong Laoonual1

Abstract: Computer simulation plays a key role in chemical process design. Currently, there are a large number of widely accepted commercial software. For example, Aspen Plus which was used to simulate offshore petroleum production processes, but it is often too costly to purchase and maintain a valid software license. On the other hand, since open-source software is freely accessible, the simulation models developed using open-source software could be studied, reviewed, and modified by any interested parties. This would help promoting technology transfer and knowledge dissemination in both academic and industry sectors. We specifically focus on the simulation of chemical process using the modeling software to evaluate thermal and chemical behaviour of the system which uses the chemical processes related to offshore petroleum production facilities as an example to demonstrate the software capabilities of both Aspen Plus and DWSIM. This work emphasizes on the comparison of simulation results calculated by commercial software namely Aspen Plus vs. open-source software called DWSIM (An open-source sequential modular steady state simulator) [1]. The simulation was carried out under the steady-state conditions, adiabatic processes, and negligible pressure losses. Finally, simulation results from DWSIM and Aspen Plus were compared with the heat and mass flow diagram which was used as reference. It was found that the discrepancy between simulation and reported values was in general less than 5%. It has been demonstrated that free and open-source software like DWSIM could potentially perform similar tasks as commercial software.

Download Link: https://iopscience.iop.org/article/10.1088/1755-1315/463/1/012057

Process Simulation Unit Operation Models - Review of Open and HSC Chemistry I/O Interfaces

Author: Marko Leino

Abstract: Chemical process modelling and simulation can be used as a design tool in the development of chemical plants, and is utilized as a means to evaluate different design options. The CAPEOPEN interface standards were developed to allow the deployment and utilization of process modelling components in any compliant process modelling environment. This thesis examines the possibilities provided by the CAPE-OPEN interfaces and the .NET framework to develop compliant, cross-platform process modelling components, particularly unit operations. From the software engineering point of view, a unit operation is a representation of physical equipment, and contains the mathematical model of its functionality. The study indicates that the differences between the CAPE-OPEN standards and Outotec HSC Chemistry Sim are negligible at the conceptual level. On the other hand, at the implementation level, the differences are quite considerable. Regardless of the simulation application being used, the modelling of unit operations requires interdisciplinary skills, and creating tools and methods to ease the development of such models is well justified. The results of this study suggest that CAPE-OPEN both provides various paths to change the way HSC Chemistry Sim works and offers the HSC development team a chance to determine an alternative way to distribute tasks between simulation components. In addition, making HSC Chemistry Sim compliant would bring benefits, such as an extended process modelling component library, and perhaps more publicity. Obviously, the workload required by the changes depends on the chosen path, which invariably entails a lengthy learning curve. This thesis contributes by helping to make that learning curve shorter.

Keywords: CAPE-OPEN, HSC Chemistry Sim, unit operation, process simulation

Download Link: https://dspace.cc.tut.fi/dpub/bitstream/handle/123456789/23943/Leino.pdf?sequence=1

Implementation of a Property Database and Thermodynamic Calculations in OpenModelica for Chemical Process Simulation

Authors: Rahul Jain, Priyam Nayak, Rahul A. S, Pravin Dalve, Kannan M. Moudgalya, P. R. Naren, Daniel Wagner, and Peter Fritzson

Publication: Ind. Eng. Chem. Res., Article ASAP; DOI: 10.1021/acs.iecr.8b05147; Publication Date (Web): February 20, 2019

Abstract: An attempt has been made to enhance the thermodynamic capability of the general purpose modeling and simulation environment OpenModelica. The property database ChemSep and the thermodynamic algorithms of DWSIM are made available in OpenModelica. The following three approaches, listed in the order of increasing computational efficiency, are attempted in this work: Python-C API, socket programming, and a native port. The most efficient method of native port is adopted to make available NRTL, Peng–Robinson, UNIFAC, and UNIQUAC algorithms in OpenModelica. Through several examples, OpenModelica results are compared with Aspen Plus, indicating a good match in all cases. This work is released as an open source to enhance the collaboration among chemical engineers.

Download link: https://pubs.acs.org/doi/abs/10.1021/acs.iecr.8b05147

Development of a Thermodynamic Engine in OpenModelica

Authors: Rahul Jain, Kannan M. Moudgalya, Peter Fritzson, Adrian Pop

Publication: Proceedings of the 12th International Modelica Conference, Prague, Czech Republic, May 15-17, 2017, Volume , Issue 132, 2017-07-04, Pages 89-99, ISSN 1650-3740

Abstract: OpenModelica, an open source equation oriented modeling environment for steady state and dynamic simulation, lacks good chemical engineering support. This problem is addressed by making available in different ways the thermodynamic library Chemsep that comes with DWSIM, an open source sequential modular steady state simulator. Only slow speeds could be achieved through a Python-C API based interface connecting OpenModelica with the thermodynamic library. A socket programming based interface helps achieve faster speeds. Best results have been achieved by porting the thermodynamic library and the calculation routines to OpenModelica, due to two reasons: (1) thermodynamic equations are solved simultaneously with mass and energy balances (2) overheads in calling the external routines of DWSIM are eliminated. Performances of the above mentioned three approaches have been validated with steady state and dynamic simulations. Benzene - toluene separation, methanol - ethanol - water distillation, and steam distillation of an n-octane - n-decane mixture, have been carried out through these simulations. This work makes available a powerful simulation platform to the chemical engineering.

Keywords: OpenModelica DWSIM Chemsep thermodynamics modeling simulation chemical engineering media Python-C API Socket programming

Download Link: http://www.ep.liu.se/ecp/132/009/ecp1713289.pdf

Scientific Papers

Evaluating strategies for monetizing natural gas liquids from processing plants – Liquid fuels versus petrochemicals

Authors: Ricardo Moreira dos Santos, Alexandre Szklo, André Lucena, Matheus Poggio

Abstract: The processing of natural gas resources is a critical step for monetizing them. Its evaluation should deal with the volatility of prices of raw gas and natural gas liquids, the processing technology and the composition of the raw gas. This study combines different approaches – process engineering, probabilistic discounted cash flow (DCF), and market failure analysis – to evaluate the technical aspects, financial results and market barriers of natural gas processing. Two productive strategies are compared: fuels or petrochemicals. Brazil is used as a case study, since the country experienced a ramping production of associated rich gas from pre-salt basins and lacks the required gas processing capacity. Findings indicate that the processing plant designed with turboexpander was able to produce the required scale for the fuel and the petrochemical markets. The Petrochemical Strategy reached a higher average net present value (US$ 2448 millions) compared to the Fuel Strategy (US$ 2006 millions) in a 30-years DCF analysis, at a higher standard deviation, however. This highlights the importance of performing the stochastic NPV to deal with price volatilities. The Petrochemical Strategy is also challenged by market failures found in Brazil, while the Fuel Strategy has social and infrastructure advantages in a stablished domestic market.

Download Link: https://www.sciencedirect.com/science/article/pii/S1875510022000075

Methyl Esters Production by Heterogeneous Catalyst Mixtures of CaO/Nb2O5 with Simulation of Analysis of Environmental Impacts

Authors: Cubides-Román, Diana C., Constantino, André F., David, Geraldo F., Martins, Lucas F., Santos, Reginaldo B. dos, Romão, Wanderson, Cunha Neto, Alvaro, & Lacerda Jr., Valdemar

Publication: Journal of the Brazilian Chemical Society, 30(3), 562-570.

Abstract: The conventional biodiesel process, although it reaches high conversion yields and productivity, faces problems related to the use of homogeneous catalysts. This work aims to study mixtures of calcium oxide (CaO) and niobium oxide (Nb2O5) as the heterogeneous catalyst. It was used a full 23 factorial design with four central points to analyze how the mass percentage of the oxides, the molar ratio of reactants, and the reaction temperature affect the conversion yield to methyl esters. The best conversion yield was found near to 89% using 1.8% of catalyst, a 1:36 oil to methanol ratio and at 77 ºC as reaction temperature. Finally, it was performed a simplified simulation to compare the heterogeneous catalyst process with the conventional process, and an algorithm to compare the effects of the exit streams of each process would have on the environment. The simulations results display a better performance for the heterogeneous catalyst process studied.

Keywords: biodiesel; heterogeneous catalyst; calcium oxide; niobium; process simulation

Download Link: http://dx.doi.org/10.21577/0103-5053.20180204

Model and Simulation of a Hydrotreatment Reactor for Diesel Hydrodesulfurization in Oil Refining

Authors: Jorge Buitrago, Dario Amaya and Olga Ramos

Publication: Contemporary Engineering Sciences, Vol. 10, 2017, no. 25, 1245-1254

Abstract: One of the most developed industries in the world is the industry dedicated to extraction and treatment of crude oil, due to his economic profitability. One of the equipment more important in any process is the reactor, which is the place where the physico-chemical transformations of the matter are carried out. The hydrotreatment process is used in oil refining, to decrease the level of different contaminants in the crude. Usually, this process is applied to the clearance of sulphur in contaminated streams. The process was modeled and simulated through the Open Source DWSIM software, using hydrogen as reactant and Ni-Mo 𝛾𝐴𝑙2𝑂3 as catalyst. As product was obtained acid crude. It was chosen the model Chao Seader to predict the main properties of each compound present in the reactor. Through the reuse of hydrogen in the system, it was possible reach a 0.0093% weight of Sulphur in the final crude stream. Furthermore, it was designed the furnace used to warm up the mixture for the reactor and the cooler used to separate the volatile compounds.

Keywords: Heavy diesel, Chemical reactor, Chemical simulation, DWSIM, Chao Seader model, HDS

Download Link: http://www.m-hikari.com/ces/ces2017/ces25-28-2017/p/amayaCES25-28-2017-1.pdf

Chemical engineering aspects of plasma-assisted CO2 hydrogenation over nickel zeolites under partial vacuum

Authors: Federico Azzolina-Jury, Diogo Bento, Carlos Henriques, Frédéric Thibault-Starzyk

Publication: Journal of CO2 Utilization, Volume 22, 2017, Pages 97-109, ISSN 2212-9820

Abstract: Ni-zeolites (ZSM-11 and USY) were prepared for application in carbon dioxide hydrogenation. Structure, physical properties and texture were analyzed by XRD, N2 sorptiometry, SEM and TEM images. The zeolites nickel reducibility (determined by in-situ TPR-MS) was directly related to the catalytic activity of zeolites. Glow-discharge plasma-assisted CO2 hydrogenation was carried out under partial vacuum using a packed-bed catalytic reactor under two different configurations: In-Plasma Catalysis (IPC) and Post-Plasma Catalysis (PPC). CO2 hydrogenation into CO (CO2+H2→CO+H2O) and CO2 methanation (CO2+4H2→CH4+2H2O) reactions were more efficient when the reaction was assisted by plasma using the IPC mode. In IPC mode, a novel phenomenon was observed: a considerable amount of methane was released from the catalyst after plasma extinction. This phenomenon was explained combining the operando IR plasma technique and the analysis of the carbon balance during the plasma-assisted CO2 hydrogenation reaction. Both configurations (IPC and PPC) were studied under different volumetric flow rates and the minimum lifetime of excited species generated within the plasma discharge for methane production was determined. The lifetime of the more active species which are responsible for methane production was lower than 67ms. Under the operation conditions used in this work, methane production was only possible when CO2 hydrogenation was performed in IPC mode. CO2 hydrogenation was found to be more energy efficient when the reaction was carried out under plasma assistance compared to conventional heating. Higher CO2 conversions, CO and CH4 yields were achieved with respect to conventional heating at lower temperatures when plasma assistance was used.

Keywords: Plasma; Glow discharge; CO2 methanation; Nickel zeolites; operando IR

Download Link: https://doi.org/10.1016/j.jcou.2017.09.017

Techno-Economic Comparison of Onshore and Offshore Underground Coal Gasification End-Product Competitiveness

Authors: Natalie Christine Nakaten, Thomas Kempka

Publication: Energies 2017, 10(10), 1643; doi:10.3390/en10101643 (registering DOI)

Abstract: Underground Coal Gasification (UCG) enables the utilisation of coal reserves that are currently not economically exploitable due to complex geological boundary conditions. Hereby, UCG produces a high-calorific synthesis gas that can be used for generation of electricity, fuels and chemical feedstock. The present study aims to identify economically competitive, site-specific end-use options for onshore and offshore produced UCG synthesis gas, taking into account the capture and storage (CCS) and/or utilisation (CCU) of resulting CO 2 . Modelling results show that boundary conditions that favour electricity, methanol and ammonia production expose low costs for air separation, high synthesis gas calorific values and H 2 /N 2 shares as well as low CO 2 portions of max. 10%. Hereby, a gasification agent ratio of more than 30% oxygen by volume is not favourable from economic and environmental viewpoints. Compared to the costs of an offshore platform with its technical equipment, offshore drilling costs are negligible. Thus, uncertainties related to parameters influenced by drilling costs are also negligible. In summary, techno-economic process modelling results reveal that scenarios with high CO 2 emissions are the most cost-intensive ones, offshore UCG-CCS/CCU costs are twice as high as the onshore ones, and yet all investigated scenarios except from offshore ammonia production are competitive on the European market. View Full-Text

Keywords: Underground Coal Gasification (UCG); economics; Cost of Electricity (COE); techno-economic model; methanol; ammonia; Carbon Capture and Storage (CCS); Carbon Capture and Utilisation (CCU); electricity generation; process simulation

Download Link: http://www.mdpi.com/1996-1073/10/10/1643

Mix-n-match Reservoir Coupling in Integrated Modeling and Optimization

Authors: Silvya Dewi Rahmawati (Petrostreamz AS/ITB) | Mohammad Faizul Hoda (Petrostreamz AS) | Daniel Wagner (CAPE-OPEN) | Arif Kuntadi (Petrostreamz AS)

Abstract: Reservoir Coupling (running multiple reservoir models in a concerted manner) features have been offered by software vendors for some time but with severe limitations. The participating models necessarily use the same vendor simulators and the models are usually limited to black-oil versions. This paper presents an integrated modeling and optimization solution with vendor independent participating simulators. The three reservoir models use simulators from different vendors (SENSOR®, ECLIPSE®, and MORE®). One model uses a black-oil PVT formulation while the other uses compositional PVT. The reservoir with the black-oil PVT model will be post-processed using consistent and accurate black-oil to compositional stream conversions. Stream conversion will utilize split factor tables to convert each phase volumetric rate to component molar rates. The split factors are a function of pressure and phase and are pre-generated simultaneously with the black-oil PVT tables. Streams from a “reduced” compositional PVT reservoir model are post-processed with another set of split factor tables, which are also a function of phase and pressure. This will allow the automated conversion of the reduced (or pseudoized) molar rates to equivalent “process” feed molar rates. The resulting comingled molar rates are delivered to the surface process simulator. An open source process simulator DWSIM® is used to model the common process facility. The sales products (gas, natural gas liquid (NGL), and oil) from the process facility model are priced in an economic model and the final results are in terms of the net present value (NPV). The optimization formulation maximizes the NPV while controlling key operating parameters of the integrated model. The approach presented in this paper can be used for integrated modeling within production sharing contracts where different companies may insist on using different reservoir simulators.

Keywords: reservoir coupling; streamz conversion; integrated model and optimization

Download Link: https://www.onepetro.org/conference-paper/IPTC-17727-MS

Development and Validation of a Thermodynamic Model for Gasification of Tyres

Author: C. Freda

Publication: Journal of Renewable and Alternative Energy Technologies, Volume 2, 2016

Abstract: A gasification model for waste tyres was developed using the commercial software DWSIM. A thermodynamic approach was adopted. The process was simulated by using air as gasifying agent. The effects of equivalence ratio and gasification temperature on the process were investigated. Equivalence ratio was varied between 0 and 1, while gasification temperature was varied between 500 and 900 °C. The model predicts the following outputs of the process: yield of producer gas and char, volumetric composition and heating value of the gas. Validation with results of experimental tests was carried out to emphasize the limits of the model.

Download Link: <a rel="nofollow" class="external free" href="http://ncerd-unn.gov.ng/joraet/index.php/JRAET/article/view/23/15">http://ncerd-unn.gov.ng/joraet/index.php/JRAET/article/view/23/15</a>

Techno-economic optimization of ethanol synthesis from rice-straw supply chains

Authors: Yohanes Kristianto, Liandong Zhu

Title: Techno-economic optimization of ethanol synthesis from rice-straw supply chains, In Energy, 2017, , ISSN 0360-5442

Abstract: The objective of this article is to design and plan sustainable bio-ethanol supply chain. Modeling supply chains that achieve economic, social and environmental feasibility through production, process and energy efficiency is a challenge. Life cycle assessment that is coupled with techno-economic optimization of bio-ethanol supply chain is an alternative solution to achieve sustainability. A simulation of the biomass conversion is used to find process parameters of the conversion technology. The results show that the unified model is capable of minimizing both CO2 emissions and energy and utility consumptions. In addition, the supply chain is capable of contributing to local economy through jobs creation. While the model is quite comprehensive, the future research recommendation on energy integration and global sustainability is proposed.

Keywords: ethanol; LCA; optimization; techno-economic analysis; rice straws; supply chains

Download Link: http://www.sciencedirect.com/science/article/pii/S0360544217315980

Simulação do Processo de Produção de Biodiesel de Óleo de Palma utilizando os softwares Aspen HYSYS e DWSIM

Authors: Machado, Nélio & Costa, Elinéia & Araújo, M.E.. (2015).

Title: SIMULAÇÃO DO PROCESSO DE PRODUÇÃO DE BIODIESEL DE ÓLEO DE PALMA UTILIZANDO OS SOFTWARES ASPEN HYSYS E DWSIM

Abstract: O biodiesel é um combustível definido na literatura como uma mistura de ésteres de ácidos graxos derivados de fontes renováveis, produzido a partir da reação de transesterificação de óleos ou gorduras com um álcool mais comumente metanol ou etanol, gerando como subproduto o glicerol. Após a reação de transesterificação ainda devem ser considerados os processos de separação para a recuperação do excesso de etanol, a separação dos ésteres do glicerol, e a purificação do biodiesel propriamente dito. O uso de simuladores comerciais representam uma ferramenta de fundamental importância para o projeto e otimização de unidades de produção como a do biodiesel, com inúmeros parâmetros importantes a serem definidos. Este trabalho teve como objetivo simular o processo de produção de Biodiesel de óleo de Palma utilizando dois diferentes simuladores de processos (o software comercial Aspen Hysys V8.4 e o software de interface aberta DWSIM V3.3). As simulações foram realizadas sob as mesmas condições operacionais em ambos os simuladores, sendo as plantas de processo constituídas da etapa de produção de ésteres via transesterificação do óleo de palma com etanol, e da etapa de purificação dos ésteres etílicos produzidos. Nas etapas de reação os dois simuladores apresentaram resultados próximos não sendo observadas diferenças significativas. Nas etapas de recuperação do etanol em excesso foram observadas diferenças nos resultados referentes às temperaturas das correntes de fundo das colunas de destilação. Analisando os resultados das duas simulações foi possível observar que a etapa de purificação e refino dos ésteres produzidos fornece resultados diferentes entre os dois simuladores. A simulação realizada com o Aspen Hysys obteve uma corrente de biodiesel majoritariamente composta por éster etílico (96,42%) isenta de Etanol e Glicerol, apresentando ainda tripalmitina (3,55%) e uma quantidade reduzida de água (0,03%); a simulação realizada com o DWSIM apresentou uma corrente de biodiesel composta por éster etílico (aproximadamente 93,19 %), isenta de água, contendo, ainda, etanol (0,16%), glicerol (2,02%) e tripalmitina (4,31%).

Download Link: https://www.researchgate.net/publication/288183538_SIMULACAO_DO_PROCESSO_DE_PRODUCAO_DE_BIODIESEL_DE_OLEO_DE_PALMA_UTILIZANDO_OS_SOFTWARES_ASPEN_HYSYS_E_DWSIM

Simulação de uma planta de produção de biodiesel

Authors: Teixeira, A.C.C.; Pereira, I.M.L.A.; Medeiros, D.; Fernandes, G.A.C.; Coelho, M.G.

Abstract: A utilização de simuladores de processo se mostra eficiente para a análise de processos industriais por tratar de uma ferramenta que além de possibilitar a visualização da planta industrial como um todo, permite também mapear os fatores que interferem diretamente no processo. Nesse contexto, o objetivo desse trabalho é simular a planta de produção de biodiesel, de forma que seja possível obter um maior percentual de biodiesel purificado. Para isso, é utilizado o software DWSIM e considera-se como matéria-prima o Óleo de Palma. Os resultados encontrados mostram que as composições da corrente do biodiesel final foi de 98,20% de éster etílico, etanol (0,05%) e tripalmitina (1,74%). Portanto, a utilização do simulador DWSIM é eficaz para análise deste processo produtivo.

Keywords: Simulação; DWSIM; Biodiesel

Download Link: http://www.abq.org.br/biocom/trabalhos_detalhes,10344.html

Avaliação da Consistência de um Projeto de Amostragem Contínua em Unidade de Processamento de Gás Natural

Author: Roberto Paulo Gomes André

Abstract: Os analisadores de processos são ferramentas importantes para o acompanhamento analítico em diversas indústrias e são aplicáveis às Unidades de Processamento de Gás Natural para monitoração e controle do processo. Esses instrumentos captam amostras e as condicionam para analisá-las de forma contínua. A compatibilização entre as condições físicas da amostra de processo para o analisador é promovida por um sistema de amostragem cujo projeto engloba o dimensionamento de vários itens com diferentes funções. Tal volume de especificações exige a adoção de critérios bem definidos de projeto a fim de mitigar falhas de implantação desses sistemas. O presente trabalho visou consolidar os critérios para o dimensionamento de um sistema de amostragem e avaliar a consistência de um projeto em uma Unidade de Processamento de Gás Natural. Mediante o conhecimento do funcionamento de uma Unidade de Processamento de Gás Natural, da configuração de um sistema de amostragem para análise desse gás e da literatura técnica aplicável, foram elencados os itens de dimensionamento dos componentes para um sistema de amostragem, levando a elaboração de uma lista de verificação de projeto. A avaliação de consistência mostrou haver aspectos na literatura consultada com diferenças significativas de especificações técnicas que podem impactar as definições de projeto. A aplicação da lista de verificação se mostrou eficaz para identificar falhas no projeto estudado neste trabalho, em especial o regime de fluxo, tempo espacial e condicionamento de temperatura. Como resultados, foi possível corrigir o desempenho do sistema, adequando o tempo espacial de 89 min para 1,2 min, eliminar o risco de condensação da amostra no sistema e a redução do consumo de energia de aquecimento de 400 W para 50 W. As correções aplicadas ao sistema tornam viável a medição analítica proposta.

Keywords: Amostragem. Gás natural. Analisadores de processos. Cromatografia.

Download Link: https://unisanta.br/arquivos/mestrado/mecanica/dissertacoes/Dissertacao_Roberto_Paulo.pdf

Thermal-Numerical Simulation of the Gas Offshore Production Undersea Facilities at the Amistad Field

Authors: Félix Gallo Cruz (Petroleum Department of Escuela Politécnica Nacional) | Andrés Leonardo Sola (Petroleum Department of Escuela Politécnica Nacional) | Joshua Andre Rosero (Petroleum Department of Escuela Politécnica Nacional) | Jaime Oswaldo Gonzalez (Petroleum Department of Escuela Politécnica Nacional)

Abstract: Thermal numerical simulation of two undersea flowlines of natural gas production at Amistad field was developed in order to avoid non-productive time caused by plugging of solid precipitation; due to the operation conditions and recorded problems during gas production in this field, a complete study of thermodynamics, heat losses and multiphase behavior of the production fluid becomes imperative to prevent and control solid formation and flow blockage. The thermodynamic behavior of gas was analytically determined based on the thermal and transport properties of fluid phases, beginning with the study of the pressure-temperature diagram of the production fluid to define the type of solids that could precipitate within the flow lines (hydrates). The heat transfer analysis was determined applying two methods, one numerical and one analytical, the numerical by the computational fluid dynamics (CFD) method with the support of the ANSYS-CFX software; and the analytical model obtained from the literature that was used to validate it. The hydrodynamic behavior of multiphase flow and pressure losses were determined by the Beggs & Brill (1973) correlation and were contrasted with the open source DWSIM software tool performance. The overall heat transfer coefficient was determined before continuing with the numerical modeling due to its importance and influence in the CFD simulation, which covers three stages: selection of the most optimum pipeline model, mesh refining, and validation of the developed model for a heat transfer phenomenon in two-phase flow. Once the heat loss model was defined by a steady state simulation, a transient simulation was carried out to calculate the gas cooling time in a case of sudden flow shutdown, considering the standard pipe currently used and three polymers of low thermal conductivity as proposed alternate materials instead of carbon-steel or as or as thermal insulation coatings, as appropriate; these are polypropylene, polyurethane and high density polyethylene. Finally, five analytical correlations of hydrate precipitation obtained from the literature and two software precipitation equilibrium curves were selected to define the precipitation scenarios of the system using the simulation results. According to the P-T diagram, the only solids that could be precipitated in the steel pipelines are methane hydrates due to the composition of the production fluid and the operating conditions of the wells. The thermal gradient of the flowlines is the most relevant result of the numerical heat transfer analysis, this one shows the critical points of the pipes where the fluid reaches its lowest temperature, that is, the temperature of the underwater current. The critical point from the wellhead for both steel lines is 5560 [ft] according to the resulting thermal gradient, although for the second line, it is actually a bit shorter due to its length limit, 5300 [ft]. From the analysis of pressure and temperature conditions at these points, two scenarios of precipitation were established considering all the equilibrium curves. Then, one of the proposed scenarios confirmed the presence of hydrates in these two production lines of the field, providing a clearer realization of the problem that includes the time, distance and critical conditions of pressure and temperature where precipitation occurs. Subsequently, the three analyzes of heat loss of the other proposed materials were compared with the results of the base case to determine the most effective pipeline configuration to avoid the formation of hydrates and it was concluded that precipitation will not occur throughout the entire flowline if any of the polymers is applied as thermal insulator or pipe material, as appropriate. In addition, the effects of the hydrodynamic phenomenon caused by the multiphase flow were studied, determining a mist flow pattern, where the liquid phase of the fluid is dispersed within the gaseous phase in the form of small water droplets.

Download Link: https://www.onepetro.org/conference-paper/OTC-29751-MS

An Organic Rankine Cycle Bottoming a Diesel Engine Powered Passenger Car

Authors: Antonio Mariani, Maria Laura Mastellone, Biagio Morrone, Maria Vittoria Prati and Andrea Unich

Abstract: Organic Rankine Cycle (ORC) power plants are characterized by high efficiency and flexibility, as a result of a high degree of maturity. These systems are particularly suited for recovering energy from low temperature heat sources, such as exhaust heat from other plants. Despite ORCs having been assumed to be appropriate for stationary power plants, since their layout, size and weight constraints are less stringent, they represent a possible solution for improving the efficiency of propulsion systems for road transportation. The present paper investigates an ORC system recovering heat from the exhaust gases of an internal combustion engine. A passenger car with a Diesel engine was tested over a Real Driving Emission (RDE) cycle. During the test exhaust gas mass flow rate and temperature have been measured, thus calculating the enthalpy stream content available as heat addition to ORC plant in actual driving conditions. Engine operating conditions during the test were discretized with a 10-point grid in the engine torque–speed plane. The ten discretized conditions were employed to evaluate the ORC power and the consequent engine efficiency increase in real driving conditions for the actual Rankine cycle. N-pentane (R601) was identified as the working fluid for ORC and R134a was employed as reference fluid for comparison purposes. The achievable power from the ORC system was calculated to be between 0.2 and 1.3 kW, with 13% system efficiency. The engine efficiency increment ranged from 2.0% to 7.5%, with an average efficiency increment of 4.6% over the RDE test.

Download Link: https://doi.org/10.3390/en13020314

Simulators Selection for Design and Simulation of a CSP-Driven Forward Osmosis Process

Authors: Samya Sigue, Souad Abderafi, Sebastion Vaudreuil, Tijani Bounahmidi

Abstract: Coupling of desalination technologies and renewable energy systems is relatively a new concept, which is used either to provide energy to a desalination system or to generate simultaneously power and drinking water. The aim of this paper is to select the most convenient simulator to study a plant combining concentrated solar power and forward osmosis dedicated to electricity and drinking water producing for populations in arid regions. Thus, a state of the art of the available steady-state simulators has been carried out. The design and simulation models and the use of these simulators in the already-published papers have been investigated. It has been revealed that there is a lack of simulators having all the required models to analyze solar energy-driven desalination processes. Thereby, most authors use two simulators, one general for chemical processes and the other specific to renewable energy systems. Besides that, simulators with pre-built models for FO unit does not exist. Open source solutions were selected over commercial ones for several reasons. They offer open access to the application elements, so new modules can be easily added or modified. Furthermore, they can interoperate and communicate with other applications. Finally, based on the supported models and development tools, we have chosen SAM and DWSIM as the suitable open source simulators for our project.

Download Link: https://ieeexplore.ieee.org/document/9078216

Chemical Process Simulation Using OpenModelica

Authors: Priyam Nayak, Pravin Dalve. Rahul Anandi Sai, Rahul Jain, Kannan M. Moudgalya, P. R. Naren, Peter Fritzson, Daniel Wagner

Abstract: The equation-oriented general-purpose simulator OpenModelica provides a convenient, extendible modeling environment, with capabilities such as an easy switch from steady-state to dynamic simulations. This work reports the creation of a library of steady-state models of unit operations using OpenModelica. The use of this library is demonstrated through a few representative flowsheets, and the results are compared with the steady-state simulators Aspen Plus and DWSIM. Being open-source and supported by a large community of developers across the world, OpenModelica provides a convenient platform to train a large number of chemical engineers to increase collaborative research and employment.

Download Link: https://pubs.acs.org/doi/abs/10.1021/acs.iecr.9b00104

Performance Comparison of Different Thermal Fluids in Concentrating Solar Plants

Authors: Maria Laura Mastellone, Antonio Mariani, Ernesto Misso, Biagio Morrone, Andrea Unich, Lucio Zaccariello

Abstract: Concentrating Solar Plants (CSP) represent a feasible alternative to fossil fuel driven power plants. Anyway, technical and economic issues severely prevent their large diffusion over the world. In this paper, a numerical investigation is accomplished to predict the performance of a CSP without thermal storage (TES). A stationary, 1-D model of heat transfer fluid (HTF) is presented, taking into account the heat losses occurring along the Heat Collector Element (HCE). A Southern Italy location is considered for the solar plant simulation, and two HTF thermal oils, Therminol VP1 and Therminol 62, are compared in terms of thermal power delivered to the power plant block. HTF temperature distribution and velocity profile along the solar plant are obtained to evaluate the performance of a coupled Organic Rankine Cycle (ORC) plant, simulated using the DWSIM programme, emphasizing the differences when using three different types of working fluids, i.e. wet, dry and isentropic.

Download Link: http://dl.astfe.org/conferences/777b4db70d8766c9,229f12d40c559b30,7569e1ce2b8d1a59.html

Análise técnico-econômica da produção de acrilonitrila via biomassa com simulação

Author: BRANDÃO, Vitor Cassuce

Abstract: O estudo tem como objetivo avaliar a rota alternativa de produção de acrilonitrila a partir de lignocelulose, analisar técnico e economicamente e simular o processo de produção através do software computacional DWSIM®. Como alternativa às matérias primas com base fóssil como o processo tradicional SOHIO, surgem os chamados processos renováveis e a proposição é de partir da biomassa lignocelulósica e obter a acrilonitrila. Foi simulada uma planta com capacidade produtiva anual de 105,5 mil toneladas de acrilonitrila. Os resultados obtidos foram de um payback de 6,3 anos e o Valor Presente Líquido do projeto é de US$ 121.671.031,32. O processo de produção a partir do propileno tem conversão de 83%, já a partir do 3-HPA é possível chegar a 97%, unidades em mol/mol. A taxa interna de retorno calculada foi de 13,58%, sendo maior que a taxa mínima de atratividade de 8% tornando o projeto viável economicamente e uma viável rota de produção de acrilonitrila.

Download Link: https://app.uff.br/riuff/handle/1/23375

Modeling and Simulation of Manufacturing Process of Paracetamol

Authors: Meda, U. S., Taher Husain, & Vora, K.

Abstract: Paracetamol also known as acetaminophen is a chemical compound derived from its chemical name N-acetyl-para-aminophenol. It is one of the most commonly used analgesics and antipyretic drugs around the world [1], as an analgesic and an antipyretic most commonly used for headaches and mild fever [2]. Paracetamol is very common and almost every individual on this planet has consumed paracetamol at least once in his/her life. So, with that extensive usage, a highly efficient production process is necessary at a large scale. Process optimization plays an important role in enhancing the efficiency of the production process. Through process optimization, the conversion can be increased, the wastage can be minimized and the product purity can be enhanced. This results in the reduction of production costs either making it profitable or affordable. Process simulation tools come very handy in designing and optimizing the processes.

In this work, the production process was modeled and simulated using open-source software, DWSIM, and the process flow diagram is shown in figure 1. The suitability of different reactors was evaluated, the separation train was optimized by varying many parameters and a sensitivity analysis was carried out. The performance of every piece of equipment involved in the process were finetuned thereby optimizing the entire process.

Download Link: https://spast.org/techrep/article/view/2648

Predicción de la producción de metanol en una planta de hidrogenación de dióxido de carbono mediante redes neuronales

Authors: Raúl Leandro Dávalos Monteiro, Mabel Mariela Parada Rivera, Jimena Alexandra Macas Macas

Abstract: El objetivo de este trabajo de investigación fue diseñar una red neuronal original (RNA) para predecir el flujo de metanol de una planta de deshidrogenación de dióxido de carbono. Para el desarrollo de ARN se generó una base de datos en el software abierto de simulación DWSIM. Ésta se realizó a partir de la validación de un proceso industrial descrito en la literatura. El tamaño de la muestra consistió en 133 pares de datos con 4 entradas: presión y temperatura del reactor, flujo másico de dióxido de carbono e hidrógeno, y una salida: flujo de metanol. La red fue de tipo perceptrón y se diseñó utilizando 12 neuronas en una capa oculta en su arquitectura, se entrenó con el algoritmo de regularización bayesiana para el entrenamiento de Levenberg-Marquardt. Se obtuvo un valor cuadrático medio (MSE) de 0,0085 y un coeficiente de regresión total de 0,9442. La red fue validada mediante el análisis de varianza (ANOVA) lo que indica que la ARN diseñada es estadísticamente válida y puede ser utilizada para predecir el flujo de metanol a la salida de la planta de deshidrogenación y puede ser utilizada como herramienta para la mejora continua de este tipo de procesos. Se recomienda añadir la presión de separación en la zona de recirculación como parámetro de entrada como forma de obtener un resultado más cercano a la realidad.

Download Link: https://dominiodelasciencias.com/ojs/index.php/es/article/view/2357

Diseño y simulación de un reactor tubular multipropósito para tri-reformado de metano

Authors: MF Rodríguez Bonilla, DM Pérez Motta

Abstract: In this work was made a study, about Methane Tri-reforming process by thermodynamic analysis of operating variables and conditions of loading to the reactor, in order to favour the conversion to synthesis gas and hydrogen, to dimension a functional catalytic reactor from a thermal and mechanical viewpoint. In addition to contextualizing chemical concepts used to carry out the project, the simulation software DWSIM was used, to demonstrate the potential of computational simulation and obtain reliable results in stable and dynamics conditions, with practical research applicable to industry, thus encourage the implementation of these technologies.

Download Link: https://repositorio.ecci.edu.co/handle/001/1556

Otimização do processo de producão de biodiesel e glicerol a partir do óleo de palma e soja por modelagem no software dwsim

Authors: Diogens Marco de Brito da Cruz, Camila Manuelle Cardoso Braz da Silva, Jeane Denise de Souza Menezes, Adeildo Moacir Costa Magalhães, Fabricio Santos de Faro

Abstract: O biodiesel é um biocombustível renovável que é obtido através de um processo químico denominado transesterificação. Por meio desse processo, os triglicerídeos presentes em diversos óleos e gorduras animais reagem com um álcool primário mais comumente adotado, o etanol ou metanol, gerando como subproduto o glicerol. Nesse sentido, a utilização de simuladores comerciais para otimização dos processos produtivos em unidades de produção de biodiesel é de fundamental importância, uma vez que estes contribuem para minimização de custos atrelados aos processos fabris. Assim, este trabalho tem por objetivo a simulação de dois processos produtivos, um contendo o óleo de palma e o outro óleo de soja, aplicando o software DWSIM v5.874. Para isso, as simulações foram realizadas adotando os mesmos parâmetros de operação, de forma a identificar como cada matéria-prima se comporta na conversão da transesterificação. Por meio das simulações, foi verificado que o óleo de palma (processo II) obteve um melhor rendimento na etapa de recuperação do etanol de reciclo, sendo observado que houve um excedente de 136,84 kg.h-1 de etanol com temperatura de 79,15 °C, quando comparado com o óleo de soja (processo I), que obteve um excedente de 152,94 kg.h-1 de etanol destilado a 79,12 °C. Analisando os resultados, foi identificado que o processo I obteve uma corrente de operação de saída de 1044,02 kg.h-1 de biodiesel a 71,68° C com 99,97% de purificação e 0,03% de impurezas na composição, e o processo II com um rendimento total de 1049,42 kg.h-1 e 99,99% de pureza e 0,01% de impurezas em sua composição final. Deste modo, foi evidenciado que o processo II obteve um maior rendimento na conversão do etanol em excesso e uma maior produção de biodiesel em relação ao processo I.

Download Link: https://www.brazilianjournals.com/index.php/BRJD/article/view/33919

Estudio comparativo de cálculo de propiedades entre programas de simulación. el caso de unisim y dwsim

Authors: CD Cañizares Gutiérrez

Abstract: Actualmente la simulación de procesos por ordenador en la ingeniería química es una etapa fundamental en la puesta en marcha y control de cualquier proceso en el campo de la petroquímica, donde permiten predecir los resultados de cualquier etapa del proceso productivo. La comparativa entre el comportamiento de dos simuladores populares, el UNISIM, disponible bajo licencia y el DWSIM, de código abierto, tiene una importancia económica significativa, ya que permite obtener resultados de un programa de aplicación industrial utilizando uno de uso académico. Delimitando el estudio para los hidrocarburos aromáticos Tolueno y Benceno, principales componentes de una mezcla BTX. Mediante la revisión de la bibliografía pertinente se estable una base teórica firme, para a continuación, proceder a modelar el comportamiento de estos componentes y una mezcla equimolar de los mismos, a través de los simuladores se obtienen las principles propiedades físico-químicas de fase y propiedades termodinámicas, luego, de aquellas propiedades que presentan mayores diferencias entre simuladores se proponen medios para corregirlas, buscando así obtener resultados con DWSIM lo más semejantes posibles a los arrojados por UNISIM, para finalizar se proponen recomendaciones para completar el estudio y poder emular el modelado de una columna de platos de simulador bajo licencia en el programa de código abierto.

Download Link: download

Simulación de producción de ácido succínico a partir de material lignocelulósico

Authors: Villota-Muñoz, B.A, Albahonza-Quenán, D.A., & Verdugo-González, L.

Abstract: El bagazo de caña es un material lignocelulósico, residuo de la producción panelera en el departamento de Nariño. En la actualidad, dicho residuo no hace parte de un proceso de transformación que le genere un valor agregado. Con el fin de contribuir al posible cierre del ciclo productivo de la caña y la generación de nuevas alternativas de trabajo en la región, en esta investigación se realizó la simulación del proceso de producción de ácido succínico (AS) a partir del bagazo de caña, teniendo en cuenta que este compuesto es un ácido carboxílico que se ha considerado como uno de los productos bioquímicos de mayor interés comercial, ya que posee una amplia gama de aplicaciones en la industria química, alimenticia y farmacéutica. Para ello se efectuó una revisión bibliográfica de los pre-tratamientos, condiciones de operación del proceso y producción biotecnológica de AS, de la cual se seleccionó una secuencia de operaciones que incluyen procesos térmicos, mecánicos, químicos y biológicos. La simulación se hizo en el software DWSIM.

Download Link: http://editorial.umariana.edu.co/revistas/index.php/BoletinInformativoCEI/article/view/2586

Síntese de metanol via hidrogenação do dióxido de carbono: modelagem e otimização no simulador DWSIM

Authors: Leandro Junior, Adilson Oliveira

Abstract: As one of the main causes of the greenhouse effect and global warming, carbon dioxide (CO2) must have its emissions progressively controlled over the years. In this context, it is interesting that it is used as a raw material for obtaining products of commercial interest, such as methanol. In this paper, a simulation of a methanol production process from the hydrogenation of carbon dioxide was performed, using the DWSIM simulator, which is an open-source, free and multiplatform software. In the simulation, some variables were chosen to be optimized in order to make the process more competitive against the traditional methanol synthesis route and to study which parameters influence the process viability. The production costs of the ton of methanol produced via hydrogenation obtained ranged from U$ 325 to U$ 1031 depending on the hydrogen source. Strategically, the direct hydrogenation of CO2 has the potential to be used as an attached process to chemical and industrial plants that have carbon dioxide as a by-product. The main challenges are the costs of obtaining hydrogen, the relatively higher energy costs and the search for efficient and viable catalysts.

Download Link: https://repositorio.ufscar.br/handle/ufscar/14537

Comparación de los costos de producción y grado de contaminación por emisiones en el sector industrial del Ecuador

Authors: López Díaz, Gabriel Junior

Abstract: En la presente investigación se realizó la comparación de los costos industriales y el grado de contaminación por emisiones que se genera utilizando los combustibles tradicionales en especial el diésel el cual es el más usado en la industria ecuatoriana frente al gas natural por medio de un programa de Ingeniería química de código abierto denominado DWSIM para la simulación de las reacciones químicas de combustión del diésel y el gas natural como generadores de energía en los procesos productivos de las Industrias, en el cual se demostró que llegando a obtener la misma cantidad de energía se pueden reducir hasta en un 22,46% de emisiones de dióxido de carbono al ambiente utilizando gas natural , también se determinó una variación de los costos de producción , el cual está en función de los costos indirectos de fabricación ya que en este elemento de los costos totales de producción se encuentran los combustibles teniendo así un ahorro de un 3,9296% al mes usado gas natural como combustible generador de energía frente al diésel como combustible tradiciona

Download Link: http://repositorio.ug.edu.ec/handle/redug/50358

Fluidos refrigerantes mistos (CO2/CH4) visando novas aplicações em sistemas de refrigeração

Authors: Matheus H. C. Garros 1,*, Robson L. Silva 1,2

Abstract: Sistemas de refrigeração utilizando fluidos refrigerantes naturais são uma demanda atual e ambientalmente relevantes, com uso comercial já existente para CO2/R-744, NH4 e alguns hidrocarbonetos. Tipicamente a obtenção do CH4 ocorre junto ao CO2, a exemplo da extração de gás natural e na produção de biogás. O objetivo é analisar um sistema de refrigeração de configuração simplificada que opere com diferentes misturas de CH4 e CO2 como fluidos de trabalho visando novas aplicações. A metodologia utiliza simulação computacional via software DWSIM para um ciclo termodinâmico e duas condições de contorno (temperatura fixada ou máximo COP). Conclui-se que maiores proporções de CO2 na mistura refrigerante implica em limitações no compressor, especificamente maior demanda de potência/trabalho e temperaturas elevadas na saída do compressor. Além disso, maiores proporções de CH4 na mistura refrigerante implica em redução na capacidade de refrigeração e menor COP. Para as condições de contorno a diferença operacional mais significativa refere-se à pressão de descarga do compressor, em geral duas vezes menor na condição de temperatura fixada em -45oC (~15 MPa). Por fim, identifica-se possível a utilização de misturas CO2/CH4 como fluidos de trabalho em sistemas de refrigeração para armazenamento de vacinas, e para aplicações em temperaturas inferiores a -50oC é necessário considerar configurações termodinâmicas mais elaboradas.

Download Link: download

Implementation of a liquid air storage system (LAES) in a mixed renewable energy system (wind and photovoltaic). The case of Tenerife

Authors: Juan Felipe Castellanos Salazar

Download Link: download

Thermodynamic and economic analyses of power generation from gas turbine exhaust

Abstract: This paper presents the development of a thermodynamic model of natural gas production processes on the offshore platform by applying Organic Rankine Cycle (ORC) technology to the plant. This research considered the thermodynamic performance and economic feasibility of using ORC for electricity production from exhaust gas generated by gas turbine engines which were used as prime movers to drive natural gas compressors. According to the Process & Instrumentation Diagram (P&ID), the process of recovering waste heat from Booster Compression and Sales Gas Compression and Export modules from the entire gas production processes of the plant has been modeled in DWSIM program which is an open-source chemical process simulation. The simulation result showed that the exhaust gas had a temperature at 527 oC at Booster Compression and 504 oC at Sale Gas Compression and Export. The ORC was designed as a simple cycle with no degree of superheating and subcooling due to limited area of the offshore platforms. We have selected the most suitable working fluid for ORC in order to get the highest turbine power and efficiency. From the simulation, Toluene was identified as the most suitable working fluid which provided the highest turbine power and efficiency at 1.9 MW and 24.33%, respectively. So, the installation of 4 cycles of ORC for offshore platform will get total energy at 7.6 MW. To demonstrate the commercial feasibility of this project, a detailed economic analysis has been performed. The results showed that the ORC technology has the net present value (NPV) is 40.141 million Baht, the payback period (PB) is around 16.49 years, the internal rate of return (IRR) is 8.18% per year (from the minimum attractive rate of return or MARR at 8% per year) and the benefit cost ratio (B/C ratio) is 1.10. All indicators show economically favorable results, thus, indicating that this research is economically feasible and worth for the investment.

Download Link: https://ph01.tci-thaijo.org/index.php/jrame/article/view/243579

Process simulation of biodiesel production from vegetable oil deodorization distillate using hydrotalcite-hydroxyapatite as catalyst

Authors: ALMEIDA, L. A. de; VILAS BÔAS, R. N.; MENDES, M. F.

Abstract: In There are few simulation studies in the literature focusing on the production of biodiesel from vegetable oil deodorization distillate (VODD), a waste originating from the vegetable oil processing stage, using hydrotalcite-hydroxyapatite as a heterogeneous catalyst. In this study, the simulation process was performed using open interface software DWSIM® Version 6.3. The motivation relied on the positive performance of the catalyst during the experimental studies. So, in the simulator design, the lipid raw material, ethanol, and the catalyst were fed together in a CSTR-01 conversion reactor. The thermodynamic fluid package used for this process was the Non-Random Two-Liquid (NRTL) activity coefficient model. The process flowchart consisted of the reaction step (oil transesterification), and separation steps of the ethyl esters produced, excess ethanol and purification of biodiesel. As a result, different scenarios were simulated, using commercial soybean oil as a comparative form, different types of catalysts and different molar ratios of alcohol and VODD. Among the main differences between the simulated cases, it was demonstrated that the excess of alcohol (1:45) caused greater quantity of VODD consumption, and consequently the greater formation of ethyl esters (biodiesel), resulting higher conversions (> 95%). In addition, the results obtained confirmed the adequacy of VODD as a potential raw material to produce biodiesel, as it is relatively cheaper than edible oils and contributes to the use of waste. Thus, confirming that the chemical catalyst was able to form the main esters of fatty acids even using a residual raw material.

Download Link: https://www.rsdjournal.org/index.php/rsd/article/view/15452

Comparative Analysis of Energy and Exergy Performance of Hydrogen Production Methods

Authors: Martínez-Rodríguez A, Abánades A.

Abstract: The study of the viability of hydrogen production as a sustainable energy source is a current challenge, to satisfy the great world energy demand. There are several techniques to produce hydrogen, either mature or under development. The election of the hydrogen production method will have a high impact on practical sustainability of the hydrogen economy. An important profile for the viability of a process is the calculation of energy and exergy efficiencies, as well as their overall integration into the circular economy. To carry out theoretical energy and exergy analyses we have estimated proposed hydrogen production using different software (DWSIM and MATLAB) and reference conditions. The analysis consolidates methane reforming or auto-thermal reforming as the viable technologies at the present state of the art, with reasonable energy and exergy efficiencies, but pending on the impact of environmental constraints as CO2 emission countermeasures. However, natural gas or electrolysis show very promising results, and should be advanced in their technological and maturity scaling. Electrolysis shows a very good exergy efficiency due to the fact that electricity itself is a high exergy source. Pyrolysis exergy losses are mostly in the form of solid carbon material, which has a very high integration potential into the hydrogen economy.

Download Link: https://www.mdpi.com/1099-4300/22/11/1286

Simulating Combined Cycle and Gas Turbine Power Plant under Design Condition using Open-Source Software DWSIM: A Comparative Study

Authors: Twana N. Hassan and Saif T. Manji

Abstract: Nowadays, clean and high-power generation is an essential matter worldwide. To be improved and optimized, power plants require accurate models that can be introduced to process simulators. There is various commercial software for industrial simulation which is not accessible to everyone. The open-source DWSIM process simulator is the first chemical engineering code that offers many tools for the better study of industrial plants. In this paper, we employ DWSIM software to simulate a combined cycle gas turbine (CCGT) power plant under design conditions for three cases. The generic models are predicted for multistage compressors and compressor maps. In the first case, two models developed in ASPEN HYSYS and GateCycle will be considered. The achieved results by DWSIM are acceptably comparable for thermal efficiency and power generation. The DWSIM result is 3.5% lower than the ASPEN HYSYS for thermal efficiency, and the power generation is completely the same. In the second case, rigorous simulation was carried out using actual field data from the local CCGT power plant. The DWSIM outcomes are very close to the practical data. The power generation of GT and CC is very close; the variety is nearly 0.45%. In the third case, the simulation of CCGT with a cogeneration system is precisely accomplished, and the outcomes of DWSIM are shown in excellent agreement. The DWSIM prediction shows lower values by 0.26%, 4.79%, and 0.72% for the HP turbine, LP turbine, and plant net power, respectively.

Download Link: http://dx.doi.org/10.14500/aro.11098

Green ammonia production via the integration of a solid oxide electrolyser and a Haber-Bosch loop with a series of solid electrolyte oxygen pumps

Authors: Duncan A. Nowicki, Gerry D. Agnew, John T.S. Irvine

Abstract: A conceptual design for a small-scale green ammonia plant is presented in which ammonia synthesis was realised via a Haber-Bosch loop using hydrogen produced by a solid oxide electrolyser and nitrogen purified from air with a series of solid electrolyte oxygen pumps. The system operated with an energetic efficiency of 52.12%, very close to a cryogenic ASU reference system where an efficiency of 52.89% was achieved. The specific energy consumption was 9.94 kWh/kgNH3. Whilst these were encouraging results, opportunities exist to improve system design further. For example, greater heat integration could allow for steam required by the electrolyser to be raised using waste heat from the series of oxygen pumps.

Download Link: https://www.sciencedirect.com/science/article/pii/S0196890423001620

Designing interactive augmented reality application for student's directed learning of continuous distillation process

Authors: Sitian Gao, Yunpeng Lu, Ching Hui Ooi, Yiyu Cai, Poernomo Gunawan

Abstract: Continuous distillation is an important separation process in chemical engineering curriculum. Conventionally, it is often taught as black box diagrams that lack user visibility, thus preventing students from developing a deeper understanding and comprehension. This paper presents the technical development of the mobile AR application and its implementation in the curriculum of Chemical Engineering Unit Operations at Nanyang Technological University Singapore. The mobile AR application is to provide interactive visualization and real-time numerical simulation to promote students’ active learning in the classroom. The results of the pre-test and post-test indicated that the AR application helped students gain a better understanding of the principle and fundamental concepts of the distillation process. The evaluation survey with 6-point likert scale questions shows that students had a positive experience using the mobile AR application and it has enhanced their learning experience, as suggested by a mean evaluation score of 5.18 out of 6.0.

Download Link: https://www.sciencedirect.com/science/article/pii/S0098135422004197

In a biogas power plant from waste heat power generation system using Organic Rankine Cycle and multi-criteria optimization

Authors: Cagatay Varis, Selin Ozcira Ozkilic

Abstract: Increasing energy consumption, rapid population growth, and technological developments have increased the need for energy demand day by day. At the point of meeting this need, renewable energy is an important alternative resource that can replace rapidly exhaustible fossil fuels. There are many renewable energy sources such as sun, wind, hydrogen, geothermal, and biogas. Biogas, one of the most important renewable energy sources, is mainly used as fuel in combined heat-power (CHP) engines/gas engines and transformed into electrical energy. However, the efficiency of these engines is low owing to the fact that a considerable amount of the energy that enters with the combustion of biogas is thrown into the atmosphere as exhaust gas. In this context, the recovery of the waste heat of 26 gas engines with a temperature of 475–500 °C in the Silivri region of Istanbul and producing biogas from household wastes was studied. Calculate the waste heat values according to the exhaust gas flow, temperature, and pressure values to be taken from the chimney outlet of the gas engines in the facility. Subsequently, the determination of the parameters of the ORC (Organic Rankine Cycle) and the optimum consumption values of the equipment in the whole system in the loop as well as the optimum ORC mechanical power will help manage and optimize the electricity production.

Download Link: https://www.sciencedirect.com/science/article/pii/S2214157X23000357

Effect of pressure on heat duties in pressure swing distillation: A simulation study

Authors: D. S. V. J. P. Koteswari M.; Vivek Kumar

Abstract: Acetone-methanol mixture is a typical minimum-boiling azeotropic system which cannot be separated in its constituent liquids using conventional techniques. At the same time, pressure swing distillation (PSD) is a separation technique which does not put the requirement of an additional third component to drive the separation process. The current work is based on the application of PSD for the minimum boiling azeotropes. The current study presents a theoretical investigation done over pressure sensitivity for the PSD of acetone-methanol mixture. Various thermodynamic models have been used. The azeotrope composition shift showed a direct effect on reboiler duty. This study also presented the optimum best operating pressure which targeted total energy consumption. DWSIM, the open source simulation software, has been used for all the simulations and it matched well with the results obtained using commercial software PRO II. The study presents the relation between high pressure column pressure and heat duty. It also discusses the possibility of heat integration and capital cost to decide the range of operating pressure.

Download Link: https://pubs.aip.org/aip/acp/article-abstract/2387/1/110002/1000016/Effect-of-pressure-on-heat-duties-in-pressure?redirectedFrom=fulltext

Transfer learning for process design with reinforcement learning

Authors: Qinghe Gao, Haoyu Yang, Shachi M. Shanbhag, Artur M. Schweidtmann

Abstract: Process design is a creative task that is currently performed manually by engineers. Artificial intelligence provides new potential to facilitate process design. Specifically, reinforcement learning (RL) has shown some success in automating process design by integrating data-driven models that learn to build process flowsheets with process simulation in an iterative design process. However, one major challenge in the learning process is that the RL agent demands numerous process simulations in rigorous process simulators, thereby requiring long simulation times and expensive computational power. Therefore, typically short-cut simulation methods are employed to accelerate the learning process. Short-cut methods can, however, lead to inaccurate results. We thus propose to utilize transfer learning for process design with RL in combination with rigorous simulation methods. Transfer learning is an established approach from machine learning that stores knowledge gained while solving one problem and reuses this information on a different target domain. We integrate transfer learning in our RL framework for process design and apply it to an illustrative case study comprising equilibrium reactions, azeotropic separation, and recycles, our method can design economically feasible flowsheets with stable interaction with DWSIM. Our results show that transfer learning enables RL to economically design feasible flowsheets with DWSIM, resulting in a flowsheet with an 8% higher revenue. And the learning time can be reduced by a factor of 2.

Download Link: https://doi.org/10.1016/B978-0-443-15274-0.50319-X

Process Simulation for Low Emission Hydrogen Production Using DWSIM

Authors: Ganesan Subramanian & Neale R. Neelameggham

Abstract: Low emission hydrogen and blended natural gas production technologies are at the forefront of meeting NETZERO50 objectives to mitigate climate change. This paper demonstrates how a chemical flowsheet simulator DWSIM (DWSIM – The Open Source Chemical Process Simulator “Chemical Process Simulation for Everyone: DWSIM for Desktop is free and open-source”, [online] Available at: https://dwsim.org [accessed August 18,1922]) is used in evaluating the effectiveness of material conversion and optimal energy requirements for thermochemical processes involving light elements C and H which are at the heart of zero or low emission fuel generation from hydrocarbons. DWSIM simulator is very flexible in that the focus can be on a single piece of equipment like a reactor where one can rigorously assess equilibrium or kinetic conversions or a complex network of an entire manufacturing facility with multiple comparison scenarios to evaluate economics.

Download Link: https://link.springer.com/chapter/10.1007/978-3-031-22524-6_107

Techno-economic analysis of hydropower based green ammonia plant for urea production in Nepal

Authors: Sijan Devkota, Sagar Ban, Rakesh Shrestha, Bibek Uprety

Abstract: This study presents a detailed design, economic, sensitivity and uncertainty analysis for establishing a hydropower based green ammonia plant for use in urea manufacturing in the context of Nepal. The electrolyzer plant for producing hydrogen was simulated with the help of DWSIM while the air separation and ammonia synthesis units were simulated with the help of Aspen Plus for producing 1245 ton/day of ammonia to meet the annual urea demand of Nepal. The capitalized cost of the electrolyzer, air separation and the ammonia synthesis unit of this size were calculated to be 26 million, 7 million and 9 million USD/year respectively. The levelized cost of hydrogen (H2) and ammonia (NH3) were found to be 3602 and 826 USD/ton respectively. Economic profitability analysis showed profitability of the plant with ROI and IRR of 38% and 26% respectively with a payback period of three years after operation. The sensitivity analysis showed strong sensitivity on the utility (electricity) cost for both the electrolyzer and ammonia synthesis unit which presents a strong opportunity for Nepal. The levelized cost for H2 and NH3 varied between 2845 USD/ton and 4361 USD/ton and 634 USD/ton and 1018 USD/ton respectively for ±30% variation in the utility (electricity) cost. Uncertainty analysis using Monte Carlo method showed the possible minimum levelized cost of H2 and NH3 to be 2340 USD/ton and 418 USD/ton respectively. This study illustrates the potential of hydropower based ammonia synthesis for urea manufacturing and provides an important baseline value for policymakers to make investment decisions and to formulate policies for this pathway of production.

Download Link: https://www.sciencedirect.com/science/article/abs/pii/S0360319923011291

Design of a liquid organic hydrogen carrier (LOHC) dehydrogenation system integrated with the concentrated solar power (CSP) plant

Authors: Nihal Rao, Vishwanath H. Dalvi, Ashwin W. Patwardhan

Abstract: The present study combines the perhydro dibenzyl toluene (PDBT) dehydrogenation reactor with the heat supplied by the heat transfer fluid, namely diphenyl ether (DPE), from the concentrated solar power (CSP) plant. The flowsheet has been simulated using the combination of DWSim v 6.5.2 and Python.NET. The dehydrogenation reactor is operated at a feed temperature between 563 K and 633 K and a pressure of 2 atm. The diphenyl ether is supplied to heat the reactor at the inlet temperature of the thermic fluid to the jacket at 663 K and 673 K. The process has been simulated to produce 10 Nm3/hr of industrial-grade hydrogen. The variation of the feed temperature, the temperature of the thermic fluid in the jacket and PDBT conversion across the catalyst weight with respect to the inlet feed temperature, the inlet temperature of the thermic fluid to the jacket and flow direction (co-current and counter-current) in the jacketed packed bed reactor (PBR) has been studied. Similarly, the weight of the catalyst required for the reactor, the area needed for the heat exchangers, and the concentrated solar power (CSP) plant have also been discussed. Cost analysis of the catalyst, concentrated solar power plant, the total annual cost of the process and the cost per kilogram of hydrogen based on the inlet feed temperature, the inlet temperature of the thermic fluid to the jacket, and the direction of the flow in the jacketed PBR have been considered. The lowest total annual cost of the process is found at the counter-current mode of operation, with the inlet feed temperature of 623 K and the inlet temperature of the thermic fluid to the jacket at 673 K.

Download Link: https://www.sciencedirect.com/science/article/abs/pii/S0360319923025855

Low-pressure steam generating heat pump – A design and field implementation case study

Authors: Sandeep Koundinya, J. Jothilingam, Satyanarayanan Seshadri

Abstract: Steam is commonly used in industries for cooking in their kitchens, and diesel or LPG-fired boilers are often used to generate it. The use of a high-temperature heat pump to generate steam can help reduce emissions and lower the CO2 footprint by eliminating these fired sources. The following study details the design and consistent operation of a steam-generating heat pump (SGHP) system that employs a high-temperature scroll compressor and functions on the principles of a vapour compression system. SGHP generates steam with a stagnation pressure of 1.5 bar, a flow rate of 81.43 kg/hr, and a temperature of 108.52 ℃. The system was simulated using DWSIM under steady-state conditions with no pressure drop, and steam was generated through a flash tank. SGHP was also installed in a canteen that previously used a diesel boiler, and data from 31 days of operation was analyzed to evaluate system performance, environmental impact, and overall savings. The system COP was 2.2. The analysis showed that an average daily energy savings of 57.79 kWh and an average cost savings of Rs. 1125.46 were achieved. SGHP (with high temperature circuit only) increased carbon emissions by 20.3 % compared to diesel, based on India's emission factor of 790 g CO2/kWh. However, considering the emission factor of the European Union, the steam-generating heat pump has the potential to reduce carbon emissions by 57.8 %.

Download Link: https://www.sciencedirect.com/science/article/abs/pii/S2451904923004936

Design considerations of the supercritical carbon dioxide Brayton cycle of small modular molten salt reactor for ship propulsion

Authors: Wonkoo Lee, Sunghyun Yoo, Dong Kyou Park, Kwon-Yeong Lee

Abstract: Recently, many studies on nuclear-powered ships as replacements for ships using fossil fuels are attracting worldwide attention. Among fourth-generation reactors, molten salt reactors (MSRs) are a suitable candidate as a power source for nuclear-powered ships because of its high efficiency and safety features. In addition, a small modular reactor (SMR) design using MSR can be developed by adopting the supercritical CO2 Brayton cycle (SCBC) as a power conversion system. The SCBC is an appropriate system for MSR-powered ships in terms of its operating temperature and compact size. In this study, we compare the design considerations of SCBC with the design requirements of a reference ship and reactor. Sensitivity studies were conducted with optimization variables, i.e., flow split ratio and pressure ratio, to determine the optimal design of the SCBC. An optimal cycle efficiency of 47.78% was obtained when the flow split ratio was 0.7 and the pressure ratio was 2.94. Finally, the SCBC was compared to a reference design using a pressurized water reactor based steam Rankine cycle. The SCBC was evaluated to be a better design for an MSR-based ship, with approximately 12% higher cycle efficiency than the reference design.

Download Link: https://www.sciencedirect.com/science/article/abs/pii/S0149197023002706

Open-source project feasibility tools for supporting development of the green ammonia value chain

Authors: Jack Shepherd, Muhammad Haider Ali Khan, Rose Amal, Rahman Daiyan, Iain MacGill

Abstract: Ammonia plays a vital role in feeding the world through fertilizer production, as well as having other industrial uses. However, current ammonia production processes rely heavily on fossil fuels, mostly natural gas, to generate hydrogen as a feedstock. There is an urgent need to re-design and decarbonise the production process to reduce greenhouse emissions and avoid dependence on volatile gas markets and a depleting resource base. Renewable energy driven electrolysis to generate hydrogen provides a viable pathway for producing carbon-free or green ammonia. However, a key challenge associated with producing green ammonia is managing low cost but highly variable wind and solar renewable energy generation for hydrogen electrolysis while maintaining reliable operation of the less flexible ammonia synthesis unit. To date, green ammonia production has only been demonstrated at pilot scale, and optimising plant configurations and scaling up production facilities is an urgent task. Existing feasibility studies have demonstrated the ability to model and cost green ammonia production pathways that can overcome the technical and economic challenges. However, these existing approaches are context specific, demonstrating the ability to model and cost green ammonia production for defined locations, with set configurations. In this paper we present a modelling framework that consolidates the array of configurations previously studied into a single framework that can be tailored to the location of interest. Our open-source green ammonia modelling and costing tool dynamically simulates the integration of renewable energy with a wide range of balancing power and storage options to meet the flexible demands of the green ammonia production process at hourly time resolution over a year or more. Unlike existing models, the open-source implementation of our tool allows it to be used by a potentially wide range of stakeholders to explore their own projects and help guide the upscaling of green ammonia as a pathway for decarbonisation. Using Gladstone in Australia as a case study, a 1 million tonne per annum (MMTPA) green ammonia plant is modelled and costed using price assumptions for major equipment in 2030 provided by the Australian Energy Market Operator (AEMO). Using a hybrid (solar PV and wind) renewable energy source and Battery Energy Storage System as balancing technology, we estimate a levelized cost of ammonia (LCOA) between 0.69 and 0.92 USD kgNH3-1. While greater than historical ammonia production costs from natural gas, falling renewables costs and emission reduction imperatives suggest a major future role for green ammonia.

Download Link: https://www.sciencedirect.com/science/article/pii/S0196890422011918

Renewable Methanol from Industrial Carbon Emissions: A Dead End or Sustainable Way Forward?

Authors: Krishnaswamy Sankaran

Abstract: As the urgency to achieve net-zero emissions by 2050 intensifies, industries face an imperative to reimagine their role in the fight against climate change. One promising avenue arises from the realization that industrial emissions, often deemed pollutants, can be the building blocks of a circular economy strategy. By directly utilizing these carbon emissions as raw materials, we can produce net-zero or low-carbon fuels, carbonates, polymers, and chemicals. At the heart of this paradigm shift lies the production of carbon-neutral methanol from industrial flue gas─a technically viable approach that has gained significant momentum in recent years. The conditions under which such a circular economy model for producing renewable methanol becomes commercially sustainable based on realistic constraints, however, are not sufficiently explored in the existing literature. This paper fills this gap by investigating if and when net-zero methanol production from industrial flue gas will be a sustainable long-term strategy. Using detailed technoeconomic modeling of integrated hydrogen and methanol production ecosystems for two production capacities, I will evaluate 32 practical production scenarios using realistic regulatory, economic, and market conditions. Even though renewable methanol from industrial emissions can be a viable technical solution to address climate change and global warming, I will show why this strategy will be commercially feasible only under favorable economic, regulatory, and market conditions. Furthermore, I will demonstrate how the market price of methanol and the cost of carbon-free electricity critically influence the commercial feasibility of this approach. When these two parameters are unfavorable, I will show why other factors, namely, carbon credits and byproduct (oxygen) sales, will not be sufficient to create an economically sustainable circular economy of renewable methanol from industrial emissions. Finally, I will provide arguments on why one has to think through stakeholder cooperation and public–private partnerships to mitigate various project risks. Despite the importance of this topic, it is not sufficiently covered in the available scientific literature. To advance policy and regulatory frameworks in this area, I strongly believe that further research and development is needed. I will also share perspectives on regulatory derisking mechanisms, which can help align regulations with private investors’ preferences. With the analyses and arguments showcased in this paper, I will firmly assert that without favorable conditions, strong partnerships, and stakeholder cooperation, the production of renewable net-zero methanol from industrial emissions risks becoming a dead-end strategy.

Download Link: https://pubs.acs.org/doi/epdf/10.1021/acsomega.3c02441