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The steel industry in China, the world's largest, contributes to about 15% of the nation's total carbon emissions. Instead of direct combustion, the technology of converting off-gas from the steel industry into liquid fuels not only enhances the added value of this byproduct but also helps alleviate carbon emissions. This study, for the first time, integrates the specific circumstances of China to evaluate the carbon emissions of Ethanol to Jet (ETJ) and Fischer–Tropsch to Jet (FTJ) fuel technologies utilizing Basic Oxygen Furnace Gas (BOFG) and Coke Oven Gas (COG) as feedstocks. Six cases were examined using Aspen Plus (V11) for mass and energy balance: Case 1: BOFG/ETJ, Case 2: BOFG/FTJ, Case 3: COG/ETJ, Case 4: COG/FTJ, Case 5: (COG + BOFG)/ETJ, and Case 6: (COG + BOFG)/FTJ. The analysis underscores that the FTJ pathway exhibits superior carbon reduction efficiency relative to ETJ. Compared to traditional petroleum-based aviation fuels (86.65 g CO2eq/MJ), the FTJ pathways utilizing COG or COG + BOFG as feedstocks exhibit significant advantages in greenhouse gas (GHG) emission reductions, with carbon emissions of 23.60 g CO2eq/MJ and 41.48 g CO2eq/MJ, respectively, representing reductions of 72.76% and 52.13%. Furthermore, employing uncertainty analysis based on the Monte Carlo method establishes the credibility of the findings. Finally, sensitivity analysis for parameter optimization and process improvements demonstrates the significant impact of the life cycle assessment (LCA) allocation method on computational results for exhaust gas feedstocks. Given the limited coverage of lifecycle assessments for Ethanol to Jet and Fischer–Tropsch to Jet pathways in China, this study could assist policymakers in determining the development trajectory of sustainable aviation fuel (SAF) in China. [ABSTRACT FROM AUTHOR]

This paper presents a computer-based methodology to support the design for additive manufacturing of metal components. Metal additive manufacturing, and in particular powder bed fusion systems, are playing a prominent role in the industry 4.0 scenario. The state of the art concerning design methods and tools to support design for additive manufacturing is reviewed by the authors. The key phases of product design and process design to achieve lightweight functional designs and reliable processes are deepened, and the computer-aided technologies to support the approaches implementation are described. Indeed, the state of the art design for additive manufacturing general workflow can be enriched by holistic approaches, use of numerical simulation, and integration and automation between the required tasks. The paper provides a methodology based on the systematic use of numerical simulation to achieve the optimization of both products and associated processes. To take advantage of the holistic perspective, the approach relies on the use of integrated product-process design platforms, allowing to streamline the digital process chain. Product design is based on the systematic integration of topology optimization and automatized tools for concept development and selection and subsequent product simulation driven design refinement. Process design is based on a systematic use of process simulation to prevent manufacturing flaws related to the high thermal gradients of metal processes and minimize residual stress and deformations. This is achieved by working on both the build cycles layouts and the 3D models' distortion compensation. An automotive use case of product and process design performed through the proposed simulation-driven integrated approach is provided to assess the actual method suitability for effective re-designs of additive manufacturing high-performance metal products. The bridged gaps are systematically outlined, and further developments are discussed. [ABSTRACT FROM AUTHOR]

H 2 has gained global attention owing to its clean energy characteristics. As an energy vector, long-term storage and transportation of H 2 in liquid form is essential which requires effective pretreatment. Standalone technologies, such as pressure swing adsorption, membrane, and cryogenic, cannot produce highly pure H 2 with high recovery in an energy-efficient manner. The integration of technologies is a promising alternative to overcome these limitations. In this regard, membrane and cryogenic (desublimation) techniques are integrated to separate H 2 with high purity and recovery. Purified H 2 is liquefied to produce 100% saturated liquid H 2 (LH 2). The proposed process is designed in Aspen Hysys v11 and evaluated with respect to energy, exergy, and economic considerations. The results have shown that the proposed process resulted in H 2 separation with 99.99% purity and 95.87% recovery. The total net energy consumption of the proposed integrated process was 11.53 kWh/kg. Exergy analysis revealed that the liquefaction section had the highest specific exergy destruction (∼92%). Moreover, the detailed economic calculations showed that the total annualized process cost was 671.6 m$/y. In this study, the potential of membrane–cryogenic integration with LH 2 production is evaluated and shown to be fundamental in the development of a sustainable H 2 economy. [Display omitted] • Membrane and desublimation technologies are integrated. • CO 2 desublimation is validated from CO 2 phase diagram. • H 2 is separated with 99.99% purity. • The proposed process consume 11.53 kWh/kg energy. • The total annualized cost of the process is 671.6 m$/y. [ABSTRACT FROM AUTHOR]

Indonesia has natural gas reservoirs with high CO 2 content, such as Natuna and Bojonegoro gas fields. Various technologies have been developed, including cryogenic distillation separation technology suitable for application to gas wells with high CO 2 content. Cryogenic distillation separates CO 2 with high purity according to the operating conditions and the CO 2 dew point. Cryogenic distillation was simulated in this study to determine the purity of the CO 2 and to compare the economic potential of each approach. The highest CO 2 purity using CFZ technology is 98.72% in the Natuna, while the highest purity of CH 4 using Pellegrini Distillation technology is 99.95% in the Bojonegoro. Economically, the Natuna and Bojonegoro estimates using the CFZ technology have a lower total annual cost than the Pelegrini distillation. However, CFZ technology has a lower CO 2 capture cost than Pellegrini Distillation technology, 7.9 USD/tonne CO 2 and 10.26 USD/tonne CO 2. In other words, separation using the CFZ technology is more effective for gas fields with higher CO 2. [Display omitted] • Indonesia has two gas fields with high CO 2 content such as Natuna and Bojonegoro. • Cryogenic technology is most economical for gas field with high CO 2 content. • CFZ concept involves the controlled freezing of CO 2 in a specially designed column. • CO 2 capture cost for CFZ lower than Pellegrini Distillation in both gas fields [ABSTRACT FROM AUTHOR]

Carbon capture and carbon reuse in the chemical plants is one of the attractive prospective approaches to decrease the concerns about global warming and climate change. In the present study, is focused on the synthesis gas production from carbon dioxide in a methanol synthesis plant. In this regard, two methanol processes are proposed based on CO 2 separation, recycling, and reforming. In the first scenario, CO 2 is separated and recycled to the conventional reformer, while the process is equipped by a CO 2 separation unit and dry methane reformer in the second scenario. The proposed processes are simulated and a sensitivity analysis is performed to investigated the effect of inputs on methanol productivity and carbon conversion. The operational parameters of proposed processes are optimized to enhance methanol productivity and CO 2 conversion. Then, the processes are compared from energy efficiency, carbon efficiency, CO 2 emission rate and methanol productivity viewpoints. The results showed that, in the second proposed scenario, methanol production rate approach to 5367 tons per day in comparison to 5030 tons per day for industrial unit. In addition, modification of conventional methanol process based on the second scenario could decrease CO 2 emission rate about 56 tons per day. [Display omitted] • Two novel methanol synthesis techniques based on CO 2 separation, recycling, and reforming were simulated. • A comparison was made between the industrial unit and two proposed configurations from the environmental and process aspect. • Various effects of operating conditions on the methanol production rate and CO 2 emissions were evaluated. • A sensitivity analysis was performed, and operational parameters were optimized to improve the proposed systems' performance. [ABSTRACT FROM AUTHOR]

• A new capture process of NH3-containing gas treatment with ionic liquids was designed. • MOGA method was employed to optimize the process operational parameters. • The comparison of water scrubbing and IL-based process was carried out. • TPC of enhanced process can be reduced by 32.41 % than water scrubbing. Ammonia (NH 3) emission has caused serious environment issues and aroused worldwide concern. The emerging ionic liquid (IL) provides a greener way to efficiently capture NH 3. This paper provides rigorous process simulation, optimization and assessment for a novel NH 3 deep purification process using IL. The process was designed and investigated by simulation and optimization using ionic liquid [C 4 im][NTF 2 ] as absorbent. Three objective functions, total purification cost (TPC), total process CO 2 emission (TPCOE) and thermal efficiency (η eff) were employed to optimize the absorption process. Process simulation and optimization results indicate that at same purification standard and recovery rate, the novel process can achieve lower cost and CO 2 emission compared to benchmark process. After process optimization, the optimal functions can achieve 0.02726 $/Nm3 (TPC), 311.27 kg CO 2 /hr (TPCOE), and 52.21% (η eff) for enhanced process. Moreover, compared with conventional process, novel process could decrease over $ 3 million of purification cost and 10000 tons of CO 2 emission during the life cycle. The results provide a novel strategy and guidance for deep purification of NH 3 capture. SYNOPSIS: This work guides to optimization of the process for NH 3 capture and NH 3 resource recovery based on ionic liquids. [Display omitted] [ABSTRACT FROM AUTHOR]

Objective The aim is to improve the qualities and yields of benzene, toluene, xylene(BTX) products and reduce the energy consumption of the unit. Methods The PETRO-SIM process simulation software was used to simulate and calculate the reforming raw materials at different initial boiling points. Aspen software was used to simulate and optimize the operating parameters of xylene tower. Results The ideal initial boiling point for the reforming feed was 82 ℃. By adjusting the operating conditions of the pre fractionation tower, the C5 component mass fraction in the reforming feed decreased by 0.79 percentage points. By implementing segmented control of reforming reaction temperature, the residual amount of methylcyclopentane in the reformed oil decreased by 0.16 percentage points, and the mass fraction of C6-C8 aromatics increased by 2.28 percentage points. The near-infrared online analysis technology was utilized to analyze data in real-time and dynamically adjust operations, the yield of xylene increased from 22.27% to 28.50%. By using Aspen software to simulate and optimize the operating parameters of the xylene tower, the yield of isomeric grade xylene at 3 ℃ increased from 23.20% to 25.60%. ConclusionsThrough production optimization, the "three increases and one decrease" efficiency goal of improving the automatic control level of the device, improving the yield and quality of aromatic products such as BTX, and reducing energy consumption has been achieved, which has reference significance for the production of aromatic products in similar devices. [ABSTRACT FROM AUTHOR]

Copyright of Low-Carbon Chemistry & Chemical Engineering is the property of Low-Carbon Chemistry & Chemical Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A process for the deoxydehydration (DODH) of glycerol to allyl alcohol in 2-hexanol as solvent was modelled with Aspen Plus. Experimental results for the DODH reaction, the liquid vapour equilibria and the catalytic hydrogenation were employed for the development of the model. The whole process consists of four subsystems: allyl alcohol production (S1), solvent recovery (S2), allyl alcohol purification (S3) and solvent regeneration (S4). Based on the results of the process model, allyl alcohol with 96% yield and a purity of 99.99% with product loss of only 0.2% was obtained. The optimisation of the energy consumption through an integrated heat exchange network resulted in a net primary energy input of 863.5 kW, which corresponded to a carbon footprint of 1.89 kgCO2/kgAllylOH. [ABSTRACT FROM AUTHOR]

The research and development of electromechanical integrated textile machinery generally has the problems of heavy field debugging workload, long cycle and high cost. Aiming at the shortcomings of the current mainstream simulation software, such as poor 3D display effect, insufficient real-time performance, or inability to connect mechanical and electronic software for comprehensive simulation, a set of semi-physical simulation system is designed. The simulation platform is built based on Unity3D virtual reality engine, and the simulation circuit board is used as the carrier to realize the real-time data interaction between the virtual machine and the control system. The lawn carpet automatic repair robot is taken as the simulation object, to prove that the semi-physical system has good real-time performance and 3D display effect. By outputting the motion sequence diagram and space trajectory diagram of the key structure of the repair robot, the process simulation feasibility of the mechanical and electrical system of the repair robot is verified, which can replace part of the field debugging, reduce the workload, shorten the development cycle, save costs, and improve the research and development efficiency of the equipment. [ABSTRACT FROM AUTHOR]

Copyright of Experimental Technology & Management is the property of Experimental Technology & Management Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Nowadays there is an urgent need for mitigating CO2 emissions through clean energy and the development of new carbon capture and utilization (CCU) technologies. Among others, the use of bifunctional ionic liquids (ILs) addressed simultaneously CO2 capture and conversion steps, having applied successfully to the propylene carbonate production case. In this work, a systematic evaluation of all representative cyclic carbonate literature was made, covering ethylene, propylene, butylene, hexylene, cyclohexene, and styrene cyclic carbonates, in order to guide the product role within the integrated CCU (ICCU) concept. The multiscale strategy combining molecular simulation (DFT -Density Functional Theory-, COSMO -COnductor-like Screening MOdel-), process simulation (COSMO/Aspen methodology), and life cycle assessment (LCA) was used to set up, simulate and evaluate the processes. ICCU configuration is the best approach when compared with sequential configuration for energy consumption analysis (reduction of 28, 28, 22, 11 and 6 %, respectively, for ethylene, propylene, butylene, hexylene, and cyclohexene cases) and CO2 emissions associated (reduction of 38, 40, 31 and 14 %, respectively, for ethylene, propylene, butylene, and hexylene cases). The main variable of the results is the boiling point of the cyclic carbonate since heavy products impose technical limitations and even discard ICCU alternative. The ICCU concept works since all cyclic carbonates’ reaction enthalpies are higher than that of the IL-CO2 one, which reduces heating requirements. Finally, energy demand can be slightly further reduced, partially recycling the cyclic carbonate to the capture unit.

A numerical model of packing applied to rigid objects is presented. It aims at describing a random stack of polymer composite chips in order to model the packing step of an existing recycling technique. The geometric properties of the stack play a major role in the mechanical properties of the recycled products. Short, simple and effective geometric descriptors of the stack are proposed. Their ability to differentiate random stacks is illustrated with an example. Then, a validation is proposed based on experimental data obtained from a bench specially designed for this work. The tests consist in the free fall of square chips. Finally, the developed model is compared to other models (free fall and packing of fibers) in order to enforce its relevance in the simulation of packing of rigid objects.

Using carbon dioxide (CO2) as a raw-material to produce value-added chemicals has a strategic role to play in the decarbonization of energy resources and the transition to a climate-neutral economy. E-methanol, Synthetic Natural Gas (SNG) and e-kerosene are one of the most promising pathways to convert CO2. In this context, the aim of this work is to propose an optimized and integrated CO2 to methanol process and then to compare it to the CO2 to SNG process from economic and environmental points of views. An optimized reactor configuration in the CO2 to methanol conversion unit has been successfully implemented in Aspen Plus® and leads to a thermal energy self-sufficiency of this unit. A heat integration with an advanced capture unit has been performed where 5 % of the heat requirement could be provided from the conversion unit while 95 % come from external steam source. Techno-economic assessment of the optimized process showed that methanol is more profitable when it is used as a raw material to synthetize other chemicals. As an energy carrier, SNG is more interesting. Compared to the reference scenario, a net CO2 emission reduction of 70 % in the CO2 to SNG route and of 60 % in the CO2 to methanol route were obtained. Concerning the fossil depletion impact, in both cases, a reduction of more than 60 % was noticed (ca. 75 % in CO2 to SNG route and 61 % in CO2 to methanol case).

Abstract The conversion of biomass residues into syngas through gasification is attractive for energy and process industry applications. However, transportation, storage, and operational challenges limit the conventional direct solid biomass gasification process. To address these issues, the intermediate conversion of biomass to bio‐oil has emerged as a promising alternative. Bio‐oil offers improved transport and storage capabilities due to its higher mass and energy density, enabling the decoupling of solid biomass supply and syngas demand. This study compares two routes for syngas production: direct gasification of solid biomass and indirect gasification using bio‐oil from biomass pyrolysis as an intermediate with biochar and pyrolysis gas supplying thermal energy to the pyrolysis stage. Biochar combustion provides about 1.4 MJ kg−1 of dry biomass to maintain the pyrolysis temperature at 480°C. Using AspenPlus® simulations, the composition and Low Heating Value of the syngas produced by both routes are analyzed. Energy and exergy analysis at different equivalence ratios and temperatures revealed that direct gasification has higher efficiencies than indirect gasification. At 1000°C and an equivalence ratio of 0.4, the highest energy and exergy efficiencies occurred in direct gasification processes. The energy efficiency of direct and indirect gasification amounted to 62% and 53%, respectively. At the same time, the corresponding exergy efficiencies were 65% and 61%. The syngas of direct and indirect gasification processes is a starting point to produce energy, synthetic fuels, and chemicals; this study provides insights for designing and optimizing biomass gasification processes.

Compared to conventional monoethanolamine (MEA), alternative solvents are expected to substantially contribute to reduce the energy demand of post-combustion CO2 capture from flue gases. This study presents a comprehensive techno-economic analysis of a 27 wt% 2-amino-2-methyl-1-propanol (AMP) + 13 wt% piperazine (PZ) aqueous solution for CO2 capture, compared to a 30 wt% MEA solution. The study addresses the retrofit of a carbon capture unit to a biomass-fired combined heat and power (CHP) plant, effectively making it a bioenergy with a carbon capture and storage (BECCS) system. The treated flue gas has a flow rate of 23 tons/hour (t/h) with 11.54 vol% CO2 and a 90% capture rate is aimed for. Aspen Plus V14 was employed for process simulations. Initially, binary interaction parameters for AMP/PZ, AMP/H2O, and PZ/H2O are regressed using vapor-liquid equilibrium (VLE) data, which were retrieved from literature along with reaction kinetics. Validation of parameters from available experimental literature yields an average absolute relative deviation (AARD) of only 5.9%. Afterwards, a process simulation model is developed and validated against experimental data from a reference pilot plant, using a similar AMP/PZ blend, resulting in 5% AARD. Next, a sensitivity analysis optimizes operating conditions, including solvent rate, absorber/stripper packing heights, and stripper pressure, based on regeneration energy impact. Optimized results, compared to MEA, reveal that AMP/PZ reduces the energy consumption from 3.61 to 2.86 GJ/tCO2. The retrofitting of the capture unit onto the selected CHP plant is examined through the development of a dedicated model. Two control strategies are compared to address energy unavailability for supplying the capture unit. The analysis spans 4 months, selected to account for seasonal variations. At nominal capacity, CO2 emissions, rendered negative by biomass combustion and CO2 capture, reach a maximum of −3.4 tCO2/h compared to 0.36 tCO2/h before retrofitting. Depending on the control strategy and CHP plant operating point, the Specific Primary Energy Consumption for CO2 Avoided (SPECCA) ranges from 4.91 MJ/kgCO2 to 1.76 MJ/kgCO2. Finally, an economic comparison based on systematic methodology reveals a 7.87% reduction in capture cost favoring the AMP/PZ blend. Together, these findings highlight AMP/PZ as a highly favorable alternative solvent.

The critical role of process simulation in modern chemical engineering cannot be overstated, with its capacity to facilitate process scale-up, assess alternative designs, and comprehend plant efficiency. This research delves into the performance of three software programs, Cape-Open to Cape-Open (CC), DWSim, and Aspen HYSYS (AH), in modeling butane dehydrogenation. The focus is on their ability to accurately model thermodynamic properties and chemical reaction dynamics. Butane dehydrogenation was evaluated with specific thermodynamic parameters using a Gibbs reactor model with Gibbs minimization. The Soave Redlich-Kwong thermodynamic model was employed to investigate the impact of temperature of 700 °C and pressures of 0.1 MPa and 1.0 MPa on the yield and selectivity of butadiene and butene. The CC and AH simulation results closely agreed with the available experimental data. The consistency of freeware simulators with a commercial simulator was also assessed, with AH serving as the reference standard. It was revealed that CC demonstrates higher consistency with it than DWSim under both low- and high-pressure conditions. This study confirms that CC is a reliable process simulator suitable for use in resource-constrained settings where expensive commercial licenses are prohibitive.

Commercial process simulation software like HYSYS® and UniSIM® are available but they require a license to operate. CAPE-OPEN to CAPE-OPEN (COCO) is a free process simulation software that includes many unit operations. In terms of material and energy balance, COCO gives very close results compared to commercial software. Gas-separation membrane can be developed manually in HYSYS® and UniSIM® using a component splitter but this unit is not available in COCO. In this work, a membrane module was built in COCO with the use of the open-source numerical computational application (Scilab). The membrane unit was developed by writing material and energy balance equations in Scilab. The equations were solved numerically by changing the permeate-cut values. The code was then integrated into COCO using the Scilab plugin. The built code was tested with an industrial membrane unit for carbon dioxide separation from flue gas. Results show that the module gives an acceptable error of 4.5 % when performing material and energy balance compared to real data.

Biogas is a renewable energy source and needs to be upgraded to biomethane for injection into the natural gas grid or use as fuel. To design ionic liquid (IL) solvents for biogas upgrading, a computer-aided ionic liquid design (CAILD) method and the corresponding process simulation are presented. The UNIFAC-IL model is employed to calculate the solubility of gases in ILs, while group contribution (GC) based models are used to predict the physicochemical properties of ILs. By using the performance index (PI) as the objective function and the structural feasibility and physicochemical properties as constraints, a mixed-integer nonlinear programming (MINLP) problem is formulated and solved by the generate-and-test method. Two IL solvents, [MMPY][Tf2N] (1,3-dimethylpyridinium bis(trifluoromethylsulfonyl)imide) and [MMPY][eFAP] (1,3-dimethylpyridinium tris(pentafluoroethyl) trifluorophosphate), are found to be the optimal IL solvents from 880 IL candidates. To perform the process simulation by using the designed ILs, the parameters for the equations of calculation of required properties are regressed. A sensitivity analysis is performed to find the optimal conditions for the process. Finally, the developed process is compared with the water-scrubbing process for biogas upgrading.

Efficient utilization of biomass as a substitute for fossil fuels holds great promise for meeting future greener chemical demands in a sustainable manner. This study presents a process simulation and multi-objective optimization for an innovative process of biomass-based Fischer-Tropsch synthesis of value-added linear α-olefins. Optimal design and operation solutions with heat-exchange network integration taken into account are obtained that minimize total annual costs (TAC), generalized energy consumption (GEC), greenhouse gas emissions (GHG), and maximize product yields (η). Compared to the benchmark case, this optimization leads to a 9.93 % reduction in TAC, a 21.76 % reduction in GEC, a 19.23 % reduction in GHG, and increases η by 1.41 %. Additionally, a comprehensive factor analysis of the optimal design and operation parameters in the Pareto front helps to discover patterns related to energy consumption, environmental impact, or economy. This allows to maximize a specific key process performance metric while minimizing the loss in the other, thus enabling flexible process design and operation under diverse manufacturing environments.

This paper presents the first integrated techno-economic and life cycle assessment of microemulsion systems being applied for rhodium-catalyzed hydroformylation of long-chain alkenes at industrial scale. The case study describes a projected 150 kt/a production of tridecanal (US gulf coast, 2019). The industrial success of the hydroformylation of short-chain alkenes lies in the continuous recycling of the rhodium-containing water phase. Microemulsion systems can be applied to transfer this concept to long-chain alkenes by overcoming the miscibility gap between the aqueous catalyst phase and the unipolar alkene phase and, moreover, by generating a temperature-induced multi-phase system enabling the immobilization of the catalyst and its continuous recycling, as demonstrated in miniplant operations with dodecene and rhodium/SulfoXantPhos. Customizable simulation models have been developed for scale-up and assessment of the miniplant data. Surprisingly, a profitability-driven sensitivity study indicates a base case optimum at low residence time with low alkene conversion leading to large throughput streams and high raw material purge rates. The comparison to the industrial cobalt-based benchmark system shows an economic advantage regarding net present value (Rh: 68 M$; Co: 62 M$), while about half of the environmental indicators are in favor or equivalent. In a best-case scenario considering zero leaching of expensive rhodium the net present value increases by almost 40% accompanied by a shift to overall lower environmental impacts than the benchmark. In conclusion, the investigated miniplant data suggest microemulsion systems to be competitive when applied in continuous processes at a large scale.

Natural gas liquefaction requires massive cold energy, but the single liquefaction process can not fully utilize the cold energy, so that much of it is wasted. Besides, storing LNG generates a large amount of BOG that demands urgent care in order to prevent production accidents. Therefore,for the purpose of energy saving, consumption reduction and full utilization of the cold energy, this study proposes an innovative co-production process combining nitrogen cyclic expansion refrigeration based natural gas liquefaction and BOG cryogenic helium extraction, This study uses the HYSYS software to simulate the nitrogen cyclic expansion refrigeration based natural gas liquefaction, the BOG cryogenic helium extraction and the co-production process, and analyzes the key parameters relating to the comprehensive energy consumption and the crude helium concentration. While maintaining the crude helium concentration at 76.8%, the co-production system, with the goal of minimizing the comprehensive energy consumption, was optimized by applying the response surface method and the genetic algorithm into the process. The optimal parameters obtained were as follows: the high pressure of the refrigerant was 7 005 kPa while the low pressure was 489 kPa and the flow rate was 4 000 kmol/h. The feed temperature and the feed pressure of the cryogenic were-130 ℃ and 2 390 kPa respectively. In the co-production process, the natural gas liquefaction rate exceeded 90%, the helium recovery rate exceeded 95%, and the crude helium volume fraction exceeded 76.8%. Compared with the single liquefaction process, the total compression power consumption in the co-production process was reduced by about 23.6%, 4 022.71 kW in number; and the overall energy consumption was reduced by about 18.00%, 3 482.4 kW in number. The simulation results suggest that the co-production process is more cost-effective and energy-efficient. This study could provide a reference for the engineering application of the newly designed co-production process.

An insightful understanding of the formation mechanism of process-inherent defects and deformation is increasingly important for the property evaluation and structural design of ceramic matrix composites (CMCs). For this purpose, a coupled thermal–diffusive–mechanical modeling approach was proposed by considering three important phenomena that occur during the pyrolysis process for manufacturing CMCs: variations of the physical and mechanical properties of the constituents, generation and diffusive of pyrolysis gas, and multiple thermal deformations. The synergistic effects of these three phenomena on the stress, damage development, microstructural morphology, and process deformation of SiC matrix composites were investigated using finite-element simulations. This new approach was validated by comparing the simulation and experimental results. Significant volume shrinkage of the matrix during the polymer-to-ceramic transformation resulted in large tensile stresses and subsequent highly fragmented microstructure in CMCs. The pyrolysis-gas-induced expansion on the matrix under a damage state may yield a positive process deformation of CMCs at the macroscale, overcoming the effects of the volume shrinkage of the bulk matrix at the microscale. The modeling approach is expected to guide high-quality manufacturing of CMCs and comprehensive studies of structure–processing–property relationships.

Iran is the second largest oil and gas producer among the Persian Gulf states, with 13.26 billion m3 gas flaring in 2020, approximately 9.34% of the global gas flaring. To reduce pollutants emissions and energy loss, an accurate feasibility study of flare gas recovery technologies is needed as the first step. Multi-objective optimization of process structure for the development of a comprehensive flare gas recovery system based on process simulation has not attracted much attention in the literature. In this study, a process structure for a flare gas recovery system was proposed using a multi-objective optimization approach to decrease associated gas flaring in southern Iran with a current flaring capacity of 279.7 MMSCFD. In the proposed structure, associated gas goes through sweetening and Natural Gas Liquids (NGL) units. After separating the liquid and vapor products, the NGL outlet gas is allocated to different units, including reinjection of gas to oil wells, gas pipelines, Liquefied Natural Gas, Compressed Natural Gas, Gas to Liquid, Gas to Power, and Desalination units. These units were simulated in Aspen HYSYS, providing an accurate economic and environmental analysis. Afterward, the shares of NGL outlet gas allocated to downstream units were considered optimization variables. The process structure was optimized by maximizing the economic (net present value) and environmental (greenhouse gas emission) objective functions. Results show that in the optimized process structure, 93.4% of the NGL outlet gas is allocated to gas injection and 6.6% to the power generation unit, resulting in a reduction of 6.22 million tons of CO2 emissions per year in this oilfield. The net present value of the flare gas recovery system is approximately 1.504 billion dollars, with a payback period of 1.60 years, suggesting the feasibility of the process.

The demand for cement has significantly increased, growing by 8% in the year 2022 and by a further 12% in 2023. It is highly anticipated that this trend will continue, and it will result in significant growth by 2030. However, cement production is highly energy-intensive, with 70 to 80% of the total energy consumed during the clinker formation, which is the main cement production process. Minimising energy losses requires a radical approach that includes optimising the performance of the kilns and significantly improving their energy efficiency. One of the most efficient approaches to optimise the performance of the kilns and reduce energy losses is by integrating process re-engineering models, which leverage process data analytics, machine learning, and computational methods. This study employed a model-based integration approach to improve energy efficiency during clinker formation. Energy consumption data were collected from two semi-automated cement production plants. The data were analysed using a regression model in Minitab (Minitab 21.1.0) statistical software. The analysis resulted in a linear energy consumption equation that links energy consumption to both production and energy loss. Dynamic simulations and modelling using Simulink in MATLAB were performed based on a proportional–integral–derivative (PID)-controlled system. The dynamic behaviour of the model was evaluated using data from Plant A and validated with data from Plant B. The energy efficiency equation was established as a mathematical model that explains energy improvements based on incorporating parameters for the cement kiln system and disturbances from the environment.

This work proposes a conceptual design for recovering polystyrene (PS) using solvents of agro-industrial origin. The literature describes the dilution of expanded polystyrene (EPS) in limonene, followed by its insolubilization with alcohols for recovery. However, there is no information on the solubility limit for the PS + limonene + alcohol system, which is critical for the process design. To determine the solubility limit, we diluted the waste EPS in D-limonene, mixed it with ethanol to form a precipitate, and used a gravimetric method to measure the mass of the compounds. These results allowed for the conceptual design of an EPS recycling process using a chemical process simulator, which includes a separator, a distillation column, and auxiliary equipment such as heaters, coolers, and pumps. An empirical correlation was obtained for the solubility limit, which enabled the design of a process for the treatment of 52 kg/s of PS using 0.75 kg/s of ethanol and 2.4 kg/s of D-limonene once the stationary state had been reached. The distillation column is six-stage, with a reflux ratio of 1.5 and duties of 30,000 and −25 847 kW for the condenser and reboiler, respectively.

This study explores the relationship between revolution pitch, heat generation, and flow properties in polypropylene friction stir welding joints. Utilizing a modified computational fluid dynamics method, simulations of polypropylene friction stir welding are conducted to elucidate material flow and thermal history in relation to revolution pitch. The study investigates the impact of revolution pitch on internal defects, hardness, and tensile strength of the polypropylene joint. Simulation results reveal that revolution pitch influences polypropylene strain rate and viscosity, leading to variations in internal voids within the stir zone. A higher revolution pitch results in vertical mixing, while a lower revolution pitch causes horizontal lamellar mixing in the stir zone. Controlling revolution pitch is crucial for producing robust joints, as a very low revolution pitch increases the risk of over-stirring and air tapping, while a very high revolution pitch hinders proper joint formation. The optimal heat range for robust joint formation is identified between ~175 (revolution pitch = 0.0410) and ~210 °C. (at revolution pitch = 0.0107). The study demonstrates that consistent polypropylene joint properties can be achieved with similar revolution pitch, even at different friction stir welding tool velocities. [ABSTRACT FROM AUTHOR]

In this study, the energy balance and techno-economic analysis of hydrothermal carbonization (HTC) of avocado stone (AS) were carried out to determine the use of hydrochar as a solid fuel. The experimental data obtained for HTC of AS were used to adjust a simulation model at an industrial scale using Aspen Plus®. The process was simulated, including all required equipment and stages to transform this biomass into dry hydrochar. The simulation result showed that the HTC process is energetically efficient for biomass water ratios above 10 wt.% at different operating temperatures (190–250 °C). The hydrochar obtained at 250 °C has a higher heating value (HHV) of up to 25.81 MJ/kg, and the energy yield of the process can reach 63.45%, while thermal efficiency reached up to 3.56 kWh of hydrochar per kWh of energy used in the process. In addition, the techno-economic analysis of the process showed that the process is economically feasible using hydrochar as pellet which has a competitive price compared to pelletized bulk pine wood, with hydrochar cost 9.64 $/GJHHV. Moreover, under the conditions studied, the initial capital recovery period was 3.7 years. This study could encourage the development of HTC plants and, therefore, the market for hydrochar pellets. [ABSTRACT FROM AUTHOR]

The key to realizing the remote utilization of hydrogen through hydrogen mixed natural gas transportation lies in the establishment of a complete set of processes from hydrogen blending to pipeline transportation to hydrogen separation. However, the assessment and study of entire process of hydrogen blended gas transportation has rarely been considered. The present study comprehensively investigates the feasibility of natural gas-hydrogen mixture transportation in a high-pressure natural gas transmission system. Specifically, this work proposes a complete set of processes for the pipeline transportation of hydrogen-doped natural gas, including the hydrogen blending process, and the hydrogen separation process. The present study investigates the impacts of various adjustable parameters based on the created simulation object on hydrogen recovery, energy consumption, and turnover rate. The results show a maximum recovery of around 94% for the whole process and a minimum SEC of 1.1 kW h/Nm3 at conventional throughput. • A whole hydrogen supply chain process based on long-distance natural gas pipeline. • Process including hydrogen blending, transmission and separation. • Undertake technical evaluations of various variable paraments for whole process. • Maximum recovery rate of around 94% for the whole process. • Minimum specific energy consumption of 1.1 kW h/Nm3 at conventional throughput. [ABSTRACT FROM AUTHOR]

In this study, using natural gas as the feedstock, a new scheme – a chemical looping combustion system with a moving bed reducer, coupled with the steam methane reforming (MCLC-SMR), is proposed and simulated for hydrogen production. This suggested process configuration is compared with other hydrogen production systems including the fluidized bed chemical looping combustion system coupled with the steam methane reforming (FCLC-SMR), the chemical looping partial oxidation system combined with the water-gas-shift reaction (CLPO-WGS), the 3-reactor chemical looping system for hydrogen generation (CLHG-3R), the conventional steam methane reforming (SMR) and auto-thermal reforming (ATR) systems with CO 2 capture. The simulation results indicate that the particle circulation rate in MCLC-SMR is 64% less than in FCLC-SMR. MCLC-SMR also shows the best system performance regarding cold gas efficiency (79%) and effective thermal efficiency (75%). The economic assessment indicates that MCLC-SMR can achieve the lowest levelized cost of hydrogen (LCOH) of $1.34/kg at 30 ton/hr H 2 production capacity, and CLHG-3R can achieve the lowest LCOH of $2.06/kg at 1 ton/hr H 2 production capacity among the six hydrogen production methods. At 30 ton/hr H 2 production capacity, the chemical looping reactors in MCLC-SMR are 37% cheaper than in FCLC-SMR. The sensitivity analysis also indicates that MCLC-SMR remains the most economical hydrogen production method over a wide range of price parameters (the prices of particles, chemical looping reactors, natural gas, and electricity). [Display omitted] • Moving bed chemical looping combustion is coupled with SMR for hydrogen production. • A novel stage-injection strategy is applied to reduce the particle circulation rate. • The proposed system yields a higher process efficiency than other conventional systems. • Levelized costs of hydrogen at different production capacities are studied. • The proposed system remains the most economical over a wide range of price parameters. [ABSTRACT FROM AUTHOR]

The development of the conceptual design of a technology for obtaining concentrated nitric acid at 99 % by weight from conventional nitric acid is presented through the analysis of 2 production alternatives, using a process simulator. For the conceptual design, process analysis techniques such as mathematical modeling, process simulation, optimization, economic analysis and Pinch analysis were used, among others. The process flow diagrams of both alternatives are also presented, as well as the validation of the mathematical model used to calculate the vapor - liquid balance in the water - nitric acid-magnesium nitrate system, as well as the sizing of the main equipment, optimizing the 2 feed and solvent inlet plates, as well as the heat transfer area of the heat exchange equipment. Finally, a summary of the economic analysis carried out for the two alternatives studied and the selection of the best one is presented. [ABSTRACT FROM AUTHOR]

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This study evaluates the techno-economic and environmental feasibility of a small-scale biorefinery in Chile's La Araucanía Region, which utilizes wheat straw as feedstock to produce butyric acid using Clostridium tyrobutyricum. Two scenarios were considered; the standalone wheat straw biorefinery and its integration with the anaerobic digestion of pig manure for biogas production, coupled with a cogeneration system, using the xylo-oligosaccharides and lignin obtained in the pretreatment. The simulations were carried out using Aspen Plus, while the Aspen Process Economic Analyzer was used to perform the economic evaluation. The simulation results were validated with experimental data from the literature. An economic assessment was performed considering the different processes involved. A cradle-to-gate life-cycle analysis (LCA) was also applied to evaluate the different environmental impacts. Both studied scenarios were economically feasible, with the highest butyric acid production cost being USD 2.97/kgbutyricacid; however, this value is still higher compared to corn-based biorefineries. Annexed biogas production increased the costs and was less economically attractive. Nonetheless, the integrations with biogas production had lower environmental impacts, except in the photochemical oxidant formation category, which was higher because of the combustion gases obtained by the cogeneration system. A lower carbon footprint (23.5 kg CO2-eq. per ton of wheat straw) was obtained for the scenario including biogas production. [ABSTRACT FROM AUTHOR]

Oily sludge is a loose material containing solid and multiple liquid components. Thermal desorption is an efficient method of disposing of liquids from oily sludge. Most existing studies have mainly discussed the effect of some external process parameters on thermal desorption, with little discussion on the heat transfer characteristics and the variation in the wet component mass of oily sludge under heating. Small-scale experiments have been performed to measure the rise in temperature and liquid phase content change of the sludge during heating. The temperature rise rate increases with material density and increases faster during the initial heating stage, while it slows down as the liquid phase evaporates. The adhesive shear stress is determined by measuring the pulling force of the test rod, which decreases with decreasing water content and increases significantly with decreasing oil phase content. Heat transfer and energy distribution models have been developed to calculate the rise in the temperature of materials and the evaporation of contained liquids. The heat and mass transfer processes are obtained from simulation calculations by taking the initial material with a mass content of 25% water and 10% oil under a heating temperature of 500 °C. When the heating time reaches 135 min, the drying region reaches the boundary of the test container, at which the material temperature exceeds 350 °C. During the evaporation of different liquid-phase components, there are multiple segments in the corresponding temperature curves. The processing time and heat source temperature can be reasonably determined by analyzing the temperature rise of the material, and the effect of the disposal of liquids from oily sludge can be predicted by analyzing the changes in liquid content. The results may guide the formulation of process parameters for engineering project schemes for oily sludge disposal. [ABSTRACT FROM AUTHOR]

Copyright of GeSec: Revista de Gestao e Secretariado is the property of Sindicato das Secretarias e Secretarios do Estado de Sao Paulo (SINSESP) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Purpose: The main goal of managing a simulation project in a manufacturing company regarding the optimization of warehouse preparation and placement of galvanized steel profiles using FlexSim software is to improve logistics processes in the warehouse and increase production efficiency. The aim of the research is to develop an effective package addressing scheme and to introduce a special code that will enable precise management of profile storage and will improve the process of completing customer orders. Design/methodology/approach: The simulation project management methodology is based on several key steps: defining goals and requirements, collecting data and modeling, designing scenarios, performing simulations, and designing an individual addressing scheme for parcels in the warehouse. Findings: Simulations allow you to find the optimal warehouse layout that ensures effective use of the available space. This, in turn, allows you to increase the storage capacity and better organize the storage of profiles, which translates into minimizing losses and costs. Simulations allow you to test different strategies for placing profiles in a warehouse to minimize the time and effort needed to find them. Optimizing the placement process allows parcels to be located faster and more precisely, which speeds up order picking. Research limitations/implications: Simulation-based process optimization requires model accuracy and reliability. Imprecise or inaccurate data can affect simulation results and lead to inappropriate decisions. This requires careful data collection and model validation before implementation. Further research may focus on optimizing routes inside the warehouse and optimizing internal logistics. Investigating the best routes and methods of transport will minimize the time your products pass through your warehouse. Research can introduce an element of random events, such as machine breakdowns or fluctuating demand, into the simulation model to better reflect real conditions and increase the reliability of the results. Practical implications: Improvement of warehouse processes and the introduction of a special code addressing the shipment can significantly reduce the risk of errors and material losses, which contributes to greater accuracy and efficiency of operation and improvement of customer relations. Social implications: Effective optimization of warehouse and production processes contributes to increased work efficiency. Reduction of redundant activities, more precise management of resources, and more efficient order picking can affect employee satisfaction as well as positively affect working conditions and security. Originality/value: The key element of originality is using advanced FlexSim software for modeling and simulation of storage processes and producing galvanized steel profiles. Simulations of this type integrated with real data and the implementation of a special package addressing code constitute a comprehensive approach to optimizing the entire process. The results of such a study can have a significant impact on the practice in manufacturing companies, enabling more effective warehouse management, shortening the time of picking orders, reducing costs, optimal use of resources, and improving the quality of customer service. It is an interdisciplinary approach that combines aspects of production management, logistics, process optimization, and the use of advanced IT tools. [ABSTRACT FROM AUTHOR]

Hydrogen (H 2) production via steam methane reforming is a mature and cost-effective technology. However, carbon capture and storage is required to decrease its carbon dioxide (CO 2) emissions. The adoption of molten carbonate fuel cells as means to capture CO 2 from flue gases is attracting scientific interest thanks to their inherent thermodynamic advantage of separating CO 2 while producing electricity. This study investigates and benchmarks the performance of an H 2 production plant equipped with molten carbonate fuel cell for post-combustion CO 2 capture, by proposing a novel configuration where the cell anode is fed with the carbon-rich off-gas from the H 2 separation unit. It emerges that the process can achieve higher capture rates than the reference solvent-based plant: 85–90% with single cell, 95% with two-stage cell. Moreover, recycling the carbon-rich off gas to the anode allows for smaller cell area, and potentially lower H 2 production costs compared to the benchmark. • CO 2 capture from steam methane reforming with molten carbonate fuel cell is studied. • A novel process based on off-gas anode feed and 2-stage cell is proposed. • Novel process achieves 90–95% CO 2 capture, against 85% natural gas fed anode process. • Novel process has smaller cell area and H 2 production cost than natural gas feed. • Novel process has comparable H 2 production cost with conventional MEA CO 2 capture. [ABSTRACT FROM AUTHOR]

Copyright of Coal Science & Technology (0253-2336) is the property of Coal Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Large volumes of bauxite residue are generated when alumina is leached from bauxite ore, within 2–3 metric tons of bauxite residue per metric ton final aluminum. The large volumes make bauxite residue an interesting source for secondary materials, for instance iron. This paper assesses environmental impacts associated with extraction of pig iron from bauxite residue in Europe. The life cycle assessment is based on thermodynamic process simulation and compares pig iron from bauxite residue with conventional pig iron production. The results indicate that the iron extraction reduces impacts on mineral scarcity and offers an overall lower waste volume. However, it also increases the energy use and thereby the life cycle impacts associated with energy production. The bauxite residue process is operated in an electric arc furnace. Decarbonizing the electricity supply, or placing the process in primarily renewable electricity markets, changes the relative competitiveness of pig iron from bauxite residue, to a level where it offers lower endpoint impacts to ecosystems, human health, and resources, as well as improvements in policy‐relevant midpoint impacts such as climate change. Comparing several bauxite residue mineralogies, the results show significant variation in the environmental performance between typical bauxite residues, yet a larger difference is observed when comparing with conventional pig iron production than among the bauxite residues. [ABSTRACT FROM AUTHOR]

An integrated LNG regasification - air separation process is investigated using exergy and exergoeconomic analyses. The objective of developing this integrated process is to lower the calorific value of LNG by mixing regasified LNG with high purity nitrogen, while simultaneously recovering and utilizing valuable cryogenic energy from the LNG during its regasification to minimize the power consumption of the air separation unit (ASU) for nitrogen production. The overall exergy efficiency and exergy destruction of the integrated process are 76.47% and 28.52 MW, respectively, with the compression section causing the most exergy destruction. Further exergoeconomic analysis of the proposed process reveals that the air compressors have the highest capital investment (CI) and operating and maintenance (O&M) cost rates, the pumps for cooling water and LNG have the highest exergoeconomic factors, and the low-pressure column and a multistream heat exchanger have the highest exergy destruction cost rates. A parametric study is also conducted to examine the impact of economic variables including interest rate, plant life, and compressor performance on exergy destruction, CI and O&M cost rates, and exergoeconomic factor. The findings of this study offer valuable insight into the design and optimization of similar integrated processes, with potential benefits for the energy industry. [ABSTRACT FROM AUTHOR]

It is impossible to overstate the value of process simulators in teaching process engineers about petrochemical, chemical, nuclear, and biological processes. Several chemical engineering topics, including process design, thermodynamics, process integration, separation processes, safety, and others, are made easier to teach because of this. Only a handful of these process simulators are freeware, while most are largely commercial. The ones that are commercialized are renowned for their friendliness, extensive media coverage, and international credibility attained for their forecasts in several industrial applications. However, schools in low-income countries may not be able to buy them. In contrast, the freeware publicity is not relatively low, less friendly, and cheaper than the commercial ones. This research compares the agreement of the forecast of commercial process simulators with freeware ones in an effort to strengthen institutions' trust in the prediction of freeware process simulators. The analysis modeled and simulated a chemical process involving the Gibbs reactor, heater, compressor, and mixer in the COCO and Aspen HYSYS simulators. Findings from the research reveal good agreement in the predicted results obtained from the various process simulators. With the use of COCO, different possible methane oxidation routes were analyzed. The analysis confirmed that the route leading to the formation of CO2 and water would be less energetic than other routes. In addition, the formation of water would be much easier in the process than hydrogen at the condition employed in the study. Due to cost, the study recommends using the freeware process simulator instead of the cracked version, which is often utilized in educating process engineers and research projects in communities where research and education are poorly funded. [ABSTRACT FROM AUTHOR]

Copyright of Chemical Engineering (China) / Huaxue Gongcheng is the property of Hualu Engineering Science & Technology Co Ltd. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

According to the process of extraction distillation in aromatics extraction unit: the separation processes of extraction distillation column, non-aromatic distillation column and solvent recovery column were studied using PRO/II simulation software・ The models of vapor-liquid equilibrium and liquid-liquid equilibrium for highly non-ideal system were selected・ The activity coefficient equation parameters and infirdte dilution activity coefficient required for the phase equilibrium calculation model of several important components, such as aromatics, olefins and solvents, were imported through manual external input, the calculation range of the models of vapor-liquid phase equilibrium was widened・ The simulation modules of column equipment, such as extraction distillation column was estabilished・ A complete simulation software package for the extraction distillation process of aromatics extraction urdt was established・ After comparison, the deviation between the simulation results and the reference data was acceptable・ The software package can be used for the engineering design of the aromatics extraction unit. The variation of infinite dilution activity coefficient of alkanes, olefins, cycloalkanes and aromatics in sulfolane with various factors was summarized. [ABSTRACT FROM AUTHOR]