Aspen Plus Research Articles

Techno-enviro-economic assessment of hydropower-driven decarbonization pathways for Nepalese cement industry

This study presents a comparative techno-enviro-economic assessment of decarbonization measures for the Nepalese cement sector, focusing on post-combustion carbon capture (PCC), use of alternative fuels and oxy-combustion techniques. A typical Nepalese clinker plant is first modelled in Aspen Plus using industrial data, the results of which is then utilized to simulate various decarbonization pathways. Performance of the measures is evaluated based on four performance indicators. The combination of oxy-combustion with hydrogen as fuel (25% thermal substitution rate) is identified as a favorable pathway compared to PCC only and combination of refuse derived fuel and PCC pathways. However, this pathway is sensitive to hydrogen byproduct price. The levelized cost of clinker (LCOC), CO2 abatement cost (CAC), specific electricity consumption for avoided CO2 and carbon intensity for this pathway are 145 USD/tclinker, 98 USD/tCO2, 1.88 MWh/tCO2 and 100 kgCO2/tclinker respectively. The LCOC value for the reference clinker plant without decarbonization is 75 USD/tclinker. The electricity consumption increased by 2153.80%, and the emissions rate decreased by 88%, compared to the reference clinker plant. Capacity utilization rates above 80% are favorable for decarbonization. Sensitivity analysis showed that a 30% decrease in the hydroelectricity cost would lower the LCOC and CAC from base values by 21.160% and 42.379% respectively. Similarly, increasing the tariff rebate to 30% would lower the LCOC and CAC for this case by 12.447% and 24.928% respectively. The results highlight a synergistic relationship between cement industry decarbonization and hydroelectricity utilization, both key targets of Nepal for net zero pathway.

Thermodynamic analysis of exhaust waste heat recovery in a compound open absorption heat pump system

To recover waste heat from flue gas in coal fired power plants and mitigate the environmental problems caused by wet flue gas, a novel compound open absorption heat pump (COAHP) system was proposed in this paper. COAHP combined the open absorption heat pump (OAHP) and the closed absorption heat pump (CAHP). The CAHP recovered the sensible heat of the flue gas before desulfurization, while the OAHP recovered the latent heat of the flue gas after desulfurization. The evaporator of the CAHP served as a cooling source for the inlet solution of the absorber of the OAHP. This system enables efficient waste heat recovery, reduces moisture levels, and eliminates wet plumes. A thermodynamic model using Aspen Plus was developed to evaluate the waste heat recovery from a 350 MW coal fired unit. In addition, the system’s performance was evaluated from the perspectives of energy analysis and exergy analysis. Liquid-gas ratio, solution inlet temperature, and secondary regeneration pressure impacted on system performance parameters and exergy efficiency. The results showed that superior water and thermal recovery efficiencies of the COAHP compared to the typical OAHP. Energy consumption for eliminating the flue gas plume decreased from 41.97 MW to 13.59 MW. When the liquid-gas ratio in the COAHP increased from 2.2 to 3.8, the water recovery efficiency increased to 72 %, the heat recovery efficiency raised to 75 %, and the coefficient of performance (COP) increased to 1.7. When the solution inlet temperature is between 40 °C and 45 °C, the heat recovery efficiency decreases to 62 %. However, the energy consumption of the system components decreases slightly, leading to a gradual increase in the COP to 1.9. The COP is maximized at a regeneration pressure of 70 kPa. At a regeneration pressure of 70 kPa, the COP reached maximum, significantly reducing the energy consumption of the vacuum pump. This work provided a feasible solution for recovering and utilizing the high-humidity flue gas waste heat following wet desulfurization in coal fired power plants.

Transforming carbon-intensive coal-fired power plants into negative emission technologies via biomass-fired calcium looping retrofit

Abstract Calcium looping is a promising CO2 capture technology due to reduced energy and economic penalties compared to mature solvent scrubbing technologies. It also can enable negative CO2 emissions when biomass is used to drive the sorbent regeneration process in the calciner. However, the trade-off between the energy, economic and environmental performance under different biomass co-firing fractions in the calciner and process operating scenarios has not yet been well understood. This study examined the potential for transforming a 580 MWel coal-fired power plant into a negative CO2 emitter via retrofit of calcium looping with biomass co-firing in the calciner. High-fidelity process models were developed in Aspen Plus and used to analyse the effect of biomass co-firing fraction, CO2 capture rate in the carbonator, and the fraction of flue gas fed to the carbonator on the techno-economic performance indicators. The results revealed that co-firing 30% biomass with coal in the calciner was sufficient for the retrofitted process to achieve negative CO2 emissions (−3.9 gCO2/kWelh). In this scenario, the levelized cost of electricity was 5% lower (81.1 €/MWelh) than that in the reference retrofit scenario without biomass co-firing (85.4 €/MWelh) at a carbon tax of 100 €/tCO2. Further improvement to the techno-economic performance was achieved by reducing the amount of CO2 captured in the carbonator by reducing either the CO2 capture rate (81.1 €/tCO2) or the amount of flue gas processed (80.4 €/tCO2). Although this was achieved at the expense of the increased specific CO2 emissions to 65.2 gCO2/kWelh and 109.0 gCO2/kWelh, respectively, the net specific emissions were still about 90% lower than those of the unabated host plant (792.3 gCO2/kWelh). This study demonstrated that depending on design priorities, biomass co-firing in the calciner can transform the existing coal-fired power plants into negative CO2 emission technologies or improve the process techno-economic viability.

Study of municipal solid waste treatment using plasma gasification by application of Aspen Plus

Abstract Plasma gasification is a viable and efficient technique for handling solid waste, including hazardous waste, while also holding the potential for energy recovery. The objective of this study is to analyze the treatment of municipal solid waste (MSW) using plasma gasification by application of Aspen Plus software. An earlier proposed model was used to analyze the effect of employing different types of gasifying agents as plasma gas, on the composition of syngas produced. The lower heating value, cold gasification efficiency and carbon conversion efficiency were calculated and compared in each case. A sensitivity analysis study was also carried out to observe the effect of variation in plasma gas flow rate and feed flow rate on the composition of syngas generated. The capital, operational and maintenance costs of the process were determined using existing correlations. For a feed rate of 20,000 kg per hour of MSW, the highest yield of syngas (CO (33.48 %), and H2 (34.30 %) with the highest LHV (7.9 MJ/N-m3)) were produced when air was employed as plasma gas. The cold gas efficiency and the carbon conversion efficiency were at their peak when air was used as the gasifying agent. The sensitivity analysis revealed that as the flow rate of plasma gas increases syngas production decreases while the increase in MSW flow rate results in an increase in syngas production. Additionally, the cost analysis revealed that for a plasma gasification plant that can handle 500 tons of MSW per day, the estimated capital and annual operational and maintenance costs are $125,496,721 and $9,833,892 respectively.

Nonlinear model predictive controller of hydrogenation of dimethyl oxalate for ethylene glycol production

Abstract Ethylene glycol (EG) is a valuable commodity organic intermediate that is produced using the catalyzed gas-phase hydrogenation process of dimethyl oxalate (DMO) from syngas. The reactor process is challenging to control because of its nonlinearity and multivariable condition. Thus, this study proposes the application of Neural Wiener model predictive control (NWMPC) for DMO hydrogenation reactor control. The application of empirical-based MPC, such as NWMPC, is still new in DMO hydrogenation reactor control. In order to simulate the process, the DMO hydrogenation reactor is modeled using Aspen Plus and Aspen Dynamic software. The Neural Wiener (NW) model is developed based on state space and neural network modeling using a Linear-Nonlinear (L-N) identification approach. A validation test is also performed to verify the accuracy of the NW model. Based on the test, the model accuracy is acceptable with the coefficient of determination (R2) of 0.965 for EG output mole fraction (first output) and R2 of 0.936 for product temperature (second output). The NWMPC capability is evaluated with a PID controller to handle a setpoint change in EG output mole fraction and reject disturbance in the feed stream flow rate. The control performance results have demonstrated the superior ability of the NWMPC to handle such scenarios better than PID in terms of controller action speed and profile.

Ant lion based optimization for performance improvement of methanol production

Abstract Methanol (CH3OH) is a versatile compound used in various industries. Catalytic reactors used in CH3OH production are expensive due to high energy and raw material costs. Multi-objective optimization (MOO) is used to optimize CH3OH production, but it is still lacking. Researchers use alternative strategies or modify existing ones to achieve better results. This study applied model-based optimization using an ASPEN Plus simulator and Multi-objective Ant Lion Optimization (MOALO) to address the issue. The results revealed the highest conversion and product rate, with the lowest energy cost, side product, and bare module cost, CBM. The decision variable plots indicate that the reactor’s pressure significantly affects the optimal solution. This study provides valuable insight into optimizing CH3OH production.

Performance Analysis and Novel Cross-Flow Scheme of Low-Temperature Multi-Effect Distillation for Treating High-Mineralized Mine Water

Low-temperature multi-effect distillation (LT-MED) can be used to desalinate and demineralize highly mineralized mine water, facilitating the recycling and reuse of water resources. This study conducted a simulation of LT-MED technology for treating highly mineralized mine water using Aspen Plus and proposed a novel cross-flow optimization scheme. Initially, the impact of operational parameters such as process configuration, number of evaporation effects, and steam input on the gained output ratio (GOR) and scaling risk of a conventional LT-MED system was analyzed. It was found that the number of effects and heating steam flow rate had the most significant influence on GOR, while different processes exhibited limitations regarding GOR and scaling trends. To address these issues, this paper introduced a cross-flow operation process that combined forward, backward, and parallel flow. The simulation results indicated that, under conditions of eight effects, a maximum evaporation temperature of 70 °C, a temperature difference between adjacent effects of 4 °C, and a feed temperature of 45 °C, the cross-flow process—where the feed was introduced from the sixth effect—achieved the highest GOR and significantly reduced scaling risks compared to parallel and backward flow configurations. Finally, to further utilize low-pressure exhaust steam from the final effect of the cross-flow LT-MED system, mechanical vapor compression (MVC) and thermal vapor compression (TVC) were integrated into the LT-MED process. The thermodynamic performance of the coupled system was analyzed, and the simulations demonstrated that the coupled system outperformed the standalone use of either TVC or MVC, with the LT-MED-MVC-TVC system showing superior performance overall.

Techno-economic feasibility study of ammonia recovery from sewage sludge digestate in wastewater treatment plants

Wastewater treatment plants play a vital role in resource recovery, particularly through biogas production, a key renewable energy source. Beyond biogas, the digestate from anaerobic digestion is rich in nutrients like ammonia. This study explored the feasibility of recovering ammonia from sewage sludge digestate using air stripping. The process was modeled using Aspen Plus® software, utilizing real data from As-Samra WWTP in Jordan. Various operational parameters, such as digestate feed flow, air flow rate, temperature, and pressure, were analyzed to optimize ammonia recovery. The results showed that with a feed flow rate between 10,000 and 30,000 kg/hr, ammonia recovery reached 85%, with production exceeding 100 kg/hr, where the effect of the flow rate appears mostly at elevated feeding temperatures. Increased air flow rates significantly boosted recovery, achieving 90% efficiency at 60 °C with 50,000 kg/h as air flow. Flashing pressure peaked at 1.5 bar, with 85% efficiency at 95 °C, while higher pressures yielded diminishing returns, stabilizing production around 106 kg/hr. The NaOH feed rate also influenced output, rising from 100 kg/hr at a 50 kg/hr feed rate to 107 kg/hr at 750 kg/hr, with recovery efficiency exceeding 85%. The economic analysis showed that the project had a payback period of 6.07 years, reflecting a reasonable recovery of the initial investment. The net present value was 122,924 USD over 15 years, with 8% amortization rate, indicating that the project created value beyond the initial cost. The internal rate of return was 14.23%, surpassing the discount rate and highlighting the project's financial attractiveness.

Analysis of syngas and power production from tannery waste via gasification process using integrated thermal equilibrium simulation model

Managing high-ash sludge from tanneries is a significant challenge and requires investigating their conversion to valuable goods. This study explores the use of gasification processes to convert tannery waste into syngas and the use of syngas for power generation. In this respect, the integrated process thermal equilibrium simulation model has been developed using the Aspen Plus® V12. This model consists of (1) a steam gasification model for syngas production and (2) a power generation model for converting syngas into electricity. In addition, sensitivity analysis has been carried out to determine the effects of temperature (650–900 °C), steam flow (500–2000 kg/h), and CaO flow (0.1500 kg/h) on the composition and power generation of syngas. Changes in steam flow rate at constant temperature (cao flow rate 1500 kg/h) show an increase in H2 content to 80 % and a decline in CO and CH4 content. This increases total power output from 3680 kW to 4001 kW, temperature increases from 650 to 900 °C, and steam flow increases from 500 to 2000 kg/h from 3500 to 4600 kW. Finally, the impact of CaO as a sorbent is significant in electricity generation and CO2 mitigation, increasing to over 600 kW of energy output. This work could contribute to converting waste into energy, which could have a significant financial impact on the tannery industry.

A Design and Safety Analysis of the “Electricity-Hydrogen-Ammonia” Energy Storage System: A Case Study of Haiyang Nuclear Power Plant

With the development of modernization, traditional fossil energy reserves are decreasing, and the power industry, as one of the main energy consumption forces, has begun to pay attention to increasing the proportion of clean energy generation. With the deepening of electrification, the peak-valley difference of residential electricity consumption increases, but photovoltaic and wind power generation have fluctuations and are manifested as reverse peak regulation. Thermal power plants as the main force of peak regulation gradually reduce the market share, making nuclear power plants bear the heavy responsibility of participating in peak regulation. The traditional method of adjusting operating power by inserting and removing control rods has great safety risks and wastes resources. Therefore, this paper proposes a new energy storage system that can keep the nuclear power plant running at full power and produce hydrogen to synthesize ammonia from excess power. A comprehensive evaluation model of energy storage based on z-score data standardization and objective parameter assignment AHP (analytic hierarchy process) analysis method was established to evaluate energy storage systems according to a multi-index system. With an AP1000 daily load tracking curve as the input model, the simulation model built by Aspen Plus V14 was used to calculate the operating conditions of the system. In order to provide a construction basis for practical engineering use, Haiyang Nuclear Power Plant in Shandong Province is taken as an example. The system layout scheme is proposed according to the local environmental conditions. The accident tree analysis method is combined with ALOHA 5.4.1.2 (Areal Locations of Hazardous Atmospheres) hazardous chemical analysis software and MARPLOT 5.1.1 geographic information technology. A qualitative and quantitative assessment of risk factors and the consequences of leakage, fire, and explosion accidents caused by hydrogen and ammonia storage processes is carried out to provide guidance for accident prevention and emergency rescue. The design of an “Electric-Hydrogen-Ammonia” energy storage system proposed in this paper provides a new idea for zero-carbon energy storage for the peak shaving of nuclear power plants and has a certain role in promoting the development of clean energy.

Sustainable Solutions for Co-Gasification of Sewage Sludge and Biomass: Insights from Aspen Plus, Response Surface Methodology, and Multi-Criteria Decision-Making Integration

This paper presents a novel framework integrating process simulation, optimization, and multi-criteria decision-making (MCDM) to identify sustainable co-gasification solutions for sewage sludge (SS) and biomass. Gasifier modeling in Aspen Plus, validated with experimental data, evaluated five feedstock blend routes. Sensitivity analysis was conducted on key gasification parameters, while Response Surface Methodology (RSM) optimized process routes by revealing complex relationships between variables and performance metrics. MCDM was applied to assess alternatives based on eight criteria covering environmental, economic, and social sustainability. The study introduced an integrated objective weighting method, leveraging data variations and correlations, alongside a vector-based ranking approach for prioritizing solutions. Results indicated that a biomass-to-sewage sludge ratio of 3:7, under co-gasification conditions of 649.72°C, 1.13atm, and a steam to feedstock ratio of 0.5, achieved the highest sustainability score of 0.506. This configuration outperformed other alternatives in terms of sustainability. Validation through three distinct analytic methods confirmed the robustness of the MCDM framework. In general, this work integrates simulation, RSM optimization, and MCDM analysis into a streamlined tool, offering a systematic progression from process simulation to decision-making. It reduces the reliance on costly trial-and-error experimentation while ensuring optimal operating conditions and comprehensive sustainability evaluation. These contributions tackle key challenges in data handling, optimization, and assessment, enabling more sustainable and cost-effective environmental technology innovations.

Simulation of Pyrolysis Process for Waste Plastics Using Aspen Plus: Performance and Emission Analysis of PPO-Diesel and PPO-Biodiesel Blends

As the global population increases, so does the usage of plastics in households, water bottles, and garbage bags, posing significant environmental threats. Plastics, being inorganic waste with long degradation periods, contaminate air, water, and soil when disposed of in landfills. Given the rise in global plastic production, effective waste management strategies are essential. This study utilized Aspen Plus simulation to analyze the pyrolysis process of waste plastics, specifically PE, PS, and LDPE. Simulations were conducted with temperature variations between 350°C to 550°C to determine the optimum conditions. Additionally, the study compared engine performance and emissions using mixtures of plastic pyrolysis oil (PPO), biodiesel from waste cooking oil (WCO), and diesel. Engine performance tests were conducted with variations in engine speed and load for PPO-diesel and PPO-biodiesel mixtures. Simulation results showed that the optimal pyrolysis temperature for the highest PPO yield was 450°C, producing 89% for PS plastic. Pyrolysis at 500°C yielded 85% oil for PE, 83% for LDPE, and 60% for mixed plastics. Engine performance tests indicated that adding PPO to diesel and WCO biodiesel significantly affected engine performance and emissions. A 5% PPO blend in diesel demonstrated better brake thermal efficiency and lower BSFC compared to higher PPO blends.

Techno-economic performance analysis of biomass-to-methanol with solid oxide electrolyzer for sustainable bio-methanol production

The analysis of the technical and economic performance of an integrated biomass to methanol and solid oxide electrolysis process (BtM-SOEC) is studied to find more sustainable process of bio-methanol production. The oil palm empty fruit branch (EFB) which is abundant in Thailand is used as biomass feedstock. Modeling of the BtM-SOEC is done using Aspen Plus. For technical aspects, the production rate of oxygen and hydrogen from the SOEC can be enhanced through an appropriate adjustment of the number of cells and cell temperature. The BtM-SOEC offers higher methanol yield and overall efficiency, while consumes less energy than the conventional biomass to methanol process (BtM). The maximum methanol production rate of 0.4995 kmol h-1 derived from BtM-SOEC is achieved at a number of cells of 325 cells and a cell temperature of 700 oC, at this condition the overall efficiency is 64.79 %. The economic assessment indicates that the conventional BtM and BtM-SOEC are still not economically feasible. However, the conventional BtM is more economically feasible than the BtM-SOEC. The methanol cost of BtM-SOEC can turn out to be economically feasible when renewable electricity cost and SOEC cost decrease substantially. The methanol cost of the BtM-SOEC (620 USD ton-1) can be competitive to that of the BtM (703 USD ton-1) when the cost of input renewable electricity decreases by 80%. Consequently, this research highlights the potential of BtM-SOEC from agricultural residues for sustainable bio-methanol production in the future market condition that the cost of renewable electricity tends to continuously decrease with the technology development and increased technology adoption and the carbon policy tends to be tightened to relieve global warming.

Abatement of Volatile Organic Compounds (VOCs) and Fluorine gases by a Microwave Plasma Torch (MPT)

The use of microwave plasma torch (MPT) in the abatement of potent greenhouse and fluorinated (F-gases) gases is crucial due to their high global warming potential. The purpose of this study was the abatement of volatile organic compounds (VOCs) and carbon tetrafluoride (CF4) using specifically designed reverse vortex flow reactor (RVR) and pillar of fire reactor (POF). The RVR has properties that are crucial for their synergistic effects with the MPT, and the POF configurations showed high-efficiency combustion due to plasma radicals and a large contact area with the MPT. The study used Aspen Plus and COMSOL software to analyse the mass balance involved in the thermal decomposition of isopropyl alcohol (C₃H₈O) and CF4 and to design the RVR and POF reactors. Using MPT without hydrocarbon fuel, low-concentration C₃H₈O and CF4 were successfully destroyed in high-flow streams. The experiment on C₃H₈O showed that using a plasma power of 2kW and 1 cubic meter per minute (CMM) of bulk gas, a destruction removal efficiency (DRE) of 95% was achieved for a polluted C₃H₈O of 410 ppm. In a second experiment, a DRE of 94% was achieved for a polluted C₃H₈O of 370 ppm. The first CF4 experiment achieved a DRE of 93.3% with a 7kW plasma power and 1 CMM bulk gas polluted at 285 ppm. In the second experiment, the presence of highly reactive hydroxyl radicals (OH⁎) in steam plasma improved the DRE to 99.8% at 7kW plasma power and 100 LPM bulk polluted at 180 ppm.

Enhanced SO2 and CO2 synergistic capture with reduced NH3 emissions using multi-stage solvent circulation process

NH3-based SO2 and CO2 synergistic capture technology shows promise in reducing the costs associated with current flue gas desulfurization and CO2 capture systems. However, it faces challenges such as NH3 slip and high energy consumption. In this study, we proposed an advanced Multi-Stage Solvent Circulation (MSC) process that incorporates a desulfurization-washing solution circulation, which involved partitioned absorption according to different functions of SO2 capture, CO2 capture, and NH3 emission control. The experimental results demonstrated that using desulfurization solution in place of water for washing reduced the NH3 emissions from the absorber and desorber by 10.6 % and 7.9 %, respectively. Additionally, the recovered NH3 enhanced SO2 capture, resulting in a 61.8 % decrease in SO2 emission concentration. A pilot-plant trial model for SO2 and CO2 synergistic capture was further developed using Aspen Plus. The impact of operational time and parameters on capture efficiency and energy consumption were analyzed. Under typical flue gas conditions, the process achieved SO2 capture efficiency of > 99 %, regeneration energy consumption of 2.42 GJ/t CO2, NH3 emissions of < 5 ppm. This study presents a novel approach for designing a SO2 and CO2 synergistic capture system, which has the potential to facilitate the economic and effective implementation of post-combustion flue gas pollutant control management and carbon emission reduction.

Feasibility assessment of Low-Carbon methanol production through 4E analysis of combined cycle power generation and carbon capture Integration

This study evaluates the feasibility of producing methanol without carbon emissions Using a comprehensive 4E (energy, exergy, economic, and environmental) approach. Our study focuses on a single methanol production system, analyzing its efficiency, sustainability, and potential as a clean fuel production method so that focusing on capturing carbon dioxide from combined cycle power generation and using the generated power to produce hydrogen through ion exchange electrolysis. The systems were simulated using Aspen Plus software, considering practical constraints to align with the capacity of existing power plants. The analysis revealed that the studied methanol production systems can produce 65.3 MW of power, with a net production power of 65.2 MW available for sale to the national grid. The annual methanol production, based on 8,000 operational hours, is 46,086 tons. The cost of methanol production is estimated at $556.69 per ton, and the environmental impact rate was calculated at 0.3726 units, with an exergy efficiency of 31.63 %. The study demonstrates that methanol can be produced efficiently using carbon capture from combined cycles, significantly reducing carbon dioxide emissions. The results suggest that while the system involves high-cost equipment, it effectively balances power generation and methanol production with a relatively low environmental impact. Future research could focus on advanced exergy analysis to identify and mitigate sources of exergy destruction, as well as optimizing carbon capture configurations and integrating solar thermal energy to enhance system sustainability further.

Development of a Large-Scale Integrated Solar-Biomass Thermal Facility for Green Production of Useful Outputs

The present paper develops a new multigeneration plant to produce multiple commodities from two combined renewable energy sources, solar thermal and biomass and considers a specific case study administered for the city of Al Lith in the Kingdom of Saudi Arabia. The plant generates power, heating, refrigeration, hydrogen, chlorine, concentrated sodium hydroxide, ammonia, urea, and fresh water, which are commodities at high demand in the area. The energy efficiency is determined to be 53% with an annual generation of over 1036 GWh of power and cogenerated 858 GWh of heating, nearly 23 GWh of refrigeration effect, over 11,300 tons of ammonia, almost 1800 tons of urea, over 113,000 tons of concentrated sodium hydroxide and over 905,000 m3 of fresh water. The exergy contents of heating, refrigeration, power and commodity products represent a total of 45% of the sources, which leads to a multigeneration platform's exergy efficiency. The system includes an integrated biomass gasification combined cycle with a biomass oxy-gasifier. The Aspen Plus simulations of the oxy-gasifier determined that the oxygen-to-biomass weight fraction should be set to 0.15, whereas the steam-to-biomass weight fraction is around 0.1. The exhaust gas recirculation is applied to enhance power generation rate and efficiency. The recirculation ratio of exhaust gas is found to be 0.21 if power generation efficiency is to be maximized and 0.28 if the power generation rate is to be maximized. The fluctuating and intermittent nature of the solar energy resource causes poor economics when this energy is to be captured in isolation or itself only. The current paper demonstrates that the hybridization of solar and biomass energy together with integrated processes for multiproduct generation enhances the overall competitivity of the renewable energy system. To address this aspect, the objective of the paper is to develop and assess a new integrated flowsheet for hybrid renewable resource multigeneration.

Maximization of Biodiesel production from oil that produced during salmon smoking process with high amount of omega-3 by using homogenous catalyst.

The escalating global demand for oil, coupled with declining fossil fuel production, prompts the urgent exploration of renewable alternatives. To address this challenge, researchers are actively seeking environmentally friendly fuels like biodiesel. Among potential feedstocks, oil that is produced from salmon smoking process during industry emerges as a promising option. Smoked salmon oil could be a challenge when producing biodiesel due to its high content of omega-3 compounds. Using homogenous commercial catalyst from alkali to achieve the highest yield from salmon smoking oil was the aim of the current study. A Box-Behnken design and response surface methodology in Design Expert software (version 13) was used to study the effect of four main factors on the biodiesel yield from salmon smoking oil. The optimum biodiesel values were 70°C, 90 min, 0.753 wt.%, and 20 wt.% for temperature, reaction time, sodium hydroxide concentration, and methanol concentration, respectively. At these optimum values, the highest biodiesel production was 92.0% with fatty acid methyl ester contents of 83.4% and conversion efficiency of 77%. Thin-layer chromatography and thermal gravimetric analysis confirmed the successful production of biodiesel at optimized conditions. Using Aspen Plus simulation software confirmed the cost-effectiveness of the homogenous catalyst used for enhancing biodiesel production from salmon smoking oil.

Simulation of a system to simultaneously recover CO2 and sweet carbon-neutral natural gas from wet natural gas: A delve into process inputs and units performances

The growing need for carbon-neutral energy solutions necessitates the development of efficient systems for carbon dioxide (CO2) recovery and the production of sweet carbon-neutral natural gas (CNNG) from wet natural gas. Despite existing approaches, limitations in process optimization, solvent efficiency, and output purity persist. This study aims to address these gaps by simulating a system for simultaneous recovery of CO2 and CNNG using an integrated three-stage process, modeled in Aspen Plus V8.8. The unique aspect of this work lies in employing the ENRTL-RK base model, coupled with sensitivity analyses to optimize input parameters across 13 interconnected process units, including compressors, heat exchangers, and extraction columns. Key innovations include the novel configuration of units, yielding a recovery efficiency of 95.94% for CNNG and a CO2 purity of 93.185% at optimal conditions, surpassing conventional methods. The performance of the monoethanolamine (MEA) solvent was enhanced by careful adjustment of input parameters, improving its absorption efficiency by 12% compared to standard operational settings. Sensitivity analysis revealed critical parameters such as feed pressure and solvent flow rate as primary drivers for maximizing output efficiency. This study also provides a detailed quantitative assessment of power requirements, with a compressor brake horsepower (BHP) of 18,2605 watts at 110 bar discharge pressure. It addresses the existing research gap by introducing a systematic approach to process optimization, significantly improving the purity and recovery of CNNG and CO2 while minimizing energy consumption. The results not only demonstrate the viability of this process but also provide a foundation for further refinement in sustainable gas processing technologies.

Techno-economic assessment of modified Fischer-Tropsch synthesis process for direct CO2 conversion into jet fuel

Direct use of CO2 through modified Fischer-Tropsch synthesis (FTS) process presents a viable approach for the production of carbon–neutral jet fuel. However, achieving high performance for the CO2-FTS process remains a significant challenge. Current technology can only achieve low CO2 conversion and low jet fuel yield using tailored catalysts, which hinders the commercial deployment of direct CO2-FTS process. This paper presents a techno-economic assessment (TEA) of jet fuel production via CO2-FTS process at commercial-scale. Two ex-situ water removal configurations: (a) multi-stage CO2-FTS process and (b) CO2-FTS with tail gas recycle process were conducted to assess their potential for performance improvement. Process performance was evaluated using a model developed in Aspen Plus® linking with Aspen Custom Modeller® (ACM), while economic evaluation was carried out in Aspen Process Economic Analyzer®. The CO2-FTS model was based on first principles and modified Anderson-Schulz-Flory (ASF) distribution. Results indicated that both ex-situ water removal configurations can significantly improve the process performance. CO2-FTS process with 90% tail gas recycle has the best performance for both technical and economic analysis. The process achieved 85.8% CO2 conversion and 35.6% jet fuel yield with the lowest energy demand of 4.57 MWh per tonne of produced jet fuel. Moreover, it boasts the lowest minimum selling price (MSP) of jet fuel at US$2.6/kg despite incurring the second-highest capital expenditure cost of M$ 451.3. A comparison of the two ex-situ water removal configurations at 61.9% and 76.5% CO2 conversion, suggests that both processes exhibit comparable technical performances, yet the recycling of tail gas holds the potential to reduce economic costs. Consequently, this study will inspire researchers on process improvement and cost reduction of the commercial-scale CO2-FTS jet fuel production.