Methanol Production Research Articles

Electrothermal Conversion of Methane to Methanol at RoomTemperature with Phosphotungstic Acid.

Traditional methods for the aerobic oxidation of methane to methanol frequently require the use of noble metal catalysts or flammable H2-O2 mixtures. While electrochemical methods enhance safety and may avoid the use of noble metals, these processes suffer from low yields due to limited current density and/or low selectivity. Here, we design an electrothermal process to conduct aerobic oxidation of methane to methanol at room temperature using phosphotungstic acid (PTA) as a redox mediator. When electrochemically reduced, PTA activates methane with O2 to produce methanol selectively. The optimum productivity reaches 29.45 [[EQUATION]] with approximately 20.3% overall electron yield. Under continuous operation, we achieved 19.90 [[EQUATION]] catalytic activity, over 74.3% methanol selectivity, and 10 hours durability. This approach leverages reduced PTA to initiate thermal catalysis in solution phase, addressing slow methane oxidation kinetics and preventing overoxidations on electrode surfaces. The current density towards methanol production increased over 40 times compared with direct electrochemical processes. The in-situ generated hydroxyl radical, from the reaction of reduced PTA and oxygen, plays an important role in the methane conversion. This study demonstrates reduced polyoxotungstate as a viable platform to integrate thermo- and electrochemical methane oxidation at ambient conditions.

Electrothermal Conversion of Methane to Methanol at Room Temperature with Phosphotungstic Acid

Traditional methods for the aerobic oxidation of methane to methanol frequently require the use of noble metal catalysts or flammable H2‐O2 mixtures. While electrochemical methods enhance safety and may avoid the use of noble metals, these processes suffer from low yields due to limited current density and/or low selectivity. Here, we design an electrothermal process to conduct aerobic oxidation of methane to methanol at room temperature using phosphotungstic acid (PTA) as a redox mediator. When electrochemically reduced, PTA activates methane with O2 to produce methanol selectively. The optimum productivity reaches 29.45 [[EQUATION]] with approximately 20.3% overall electron yield. Under continuous operation, we achieved 19.90 [[EQUATION]] catalytic activity, over 74.3% methanol selectivity, and 10 hours durability. This approach leverages reduced PTA to initiate thermal catalysis in solution phase, addressing slow methane oxidation kinetics and preventing overoxidations on electrode surfaces. The current density towards methanol production increased over 40 times compared with direct electrochemical processes. The in‐situ generated hydroxyl radical, from the reaction of reduced PTA and oxygen, plays an important role in the methane conversion. This study demonstrates reduced polyoxotungstate as a viable platform to integrate thermo‐ and electrochemical methane oxidation at ambient conditions.

Exploring complete catalytic cycle of methane oxidation to methanol on Cu2O2 stabilized within MIL-53(Al) framework: A combined DFT and microkinetic study

Although inspiration from copper-based natural enzymes has shown promise in improving catalyst design for methane-to-methanol (MTM) oxidation, high productivity, and selectivity under mild conditions remain a significant challenge. This study constructs the dinuclear copper (Cu2) species stabilized within the metal-organic framework (MOF), MIL-53(Al), containing Cu as efficient catalytic sites and explores the ability of different oxidants (O2, N2O, and H2O2) to oxidize Cu2 into the dicopper-oxo (Cu2O2) species using density functional theory (DFT) calculations. Our results indicate the kinetic and thermodynamic favorability of Cu2O2 species formation using O2 as an oxidant within the MIL-53(Al) framework. Furthermore, the thermal stability of Cu2O2/MIL-53(Al) has been verified via ab initio molecular dynamics (AIMD) calculations. The kinetics of the complete MTM oxidation cycle over Cu2O2/MIL-53(Al) have been studied using both DFT and microkinetic simulation methods. The present study predicts that the C-H activation on the Cu2O2/MIL-53(Al) has a low free energy barrier (0.77 eV) and that the high stability of CH3 and its very low free energy barrier in the C-O coupling step favors the methanol formation over the formaldehyde. More importantly, Cu2O2/MIL-53(Al) exhibits high methanol selectivity owing to the inhibition of CH3 dehydrogenation and low methanol desorption energy (0.21 eV). Microkinetic simulations confirm the methanol production under relatively mild reaction conditions (200–280 K and 1 bar). This work provides insights into the feasibility of selective MTM oxidation over this family of MOF under mild conditions.

Enhanced Selectivity to Methanol in CO2 Hydrogenation on CuO/ZrO2 Catalysts by Alkali Metal Modification

AbstractIn order to alleviate the influence of greenhouse effect on global climate change, the effective utilization of CO2 to prepare fine chemicals should be paid more attention to, however, which is greatly blocked by the catalyst with low efficiency. Here, alkali metal (Li, Na, or K) are employed as a modification aid to prepare CuO/ZrO2 catalyst for CO2 hydrogenation to methanol. The effects of alkali metal on physicochemical properties and catalytic activities of CuO/ZrO2 catalyst were studied in detail by the XRD, N2‐physisorption, ICP‐OES, SEM/EDS, H2/N2O/CO2/NH3‐chemisorption, and evaluation test. The results verified that the use of complex combustion method enabled the uniform combination of all components in precursor. High‐temperature calcination (700 °C) further enhanced the strong interaction and synergistic effect between Cu and ZrO2. Most importantly, the introduction of alkali metal effectively altered the structure and catalytic activity of CuO/ZrO2 catalysts. However, the selectivity to methanol increased while the CO2 conversion decreased regardless of different kinds of alkali metal being introduced to the CuO/ZrO2 catalysts. For example, CuO/ZrO2 catalyst modified by K exhibited excellent performance for methanol production that 98.9% selectivity of methanol based on 8.8% conversion of CO2 after 48 h online reaction.

PULPO: A framework for efficient integration of life cycle inventory models into life cycle product optimization

AbstractThis work presents the PULPO (Python‐based user‐defined lifecycle product optimization) framework, developed to efficiently integrate life cycle inventory (LCI) models into life cycle product optimization. Life cycle optimization (LCO), which has found interest in both the process systems engineering and life cycle assessment (LCA) communities, leverages LCA data to go beyond simple assessments of a limited number of alternatives and identify the best possible product systems configuration subject to a manifold of choices, constraints, and objectives. However, typically, aggregated inventories are used to build the optimization problems. Contrary to existing frameworks, PULPO integrates whole LCI databases and user inventories as a backbone for the optimization problem, considering economy‐wide feedback loops between fore‐ and background systems that would otherwise be omitted. The open‐source implementation combines functions from Brightway2 for the manipulation of inventory data and pyomo for the formulation and solution of the optimization problem. The advantages of this approach are demonstrated in a case study focusing on the design of optimal future global green methanol production systems from captured CO2 and electrolytic H2. It is shown that the approach can be used to assess sector‐coupling with multi‐functional processes and prospective background databases that would otherwise be impractical to approach from a standalone LCA perspective. The use of PULPO is particularly appealing when evaluating large‐scale decisions that have a strong impact on socioeconomic systems, resulting in changes in the technosphere on which the background system is based and which is often assumed constant in standard LCO approaches regardless of the decisions taken. This article met the requirements for a gold‐gold JIE data openness badge described at http://jie.click/badges.

Selective methanol production via CO2 reduction on Cu2O revealed by micro-kinetic study combined with constant potential model

High efficiency electrocatalysis of greenhouse gas CO2 to liquid fuel methanol attracts great attentions that allows energy transformation from renewable electric energy to storable chemical energy. Catalytically converting CO2 to methanol using green hydrogen is a promising pathway to achieve carbon neutrality. In this work, the catalytic activity and product selectivity of the electrochemical CO2 reduction reaction on Cu2O were studied using a micro-kinetic model based on Marcus charge transfer theory. The constant potential model under the grand-canonical ensemble enables the accurate description of binding energies and ground-state charge transfer upon surface adsorption as a function of electrode potential. Firstly, the potential-dependent activation energies and rate constants of all possible elementary reactions involved in CO2 reduction are calculated. Then, the surface coverage and its derivative can be obtained in a steady-state approximation. Finally, the total reaction rate and partial reaction rate can be deduced, allowing for direct comparison with catalytic activity (current density) and product selectivity (Faradaic efficiency). It is found that CH3OH is the dominant product on the Cu2O(111) surface, while CO is the main product on the Cu2O(110) surface. Based on the derived total and partial reaction rates under the steady-state approximation, it is demonstrated that Cu2O(111) exhibits the highest electrocatalytic activity and methanol selectivity at U = −0.6 V vs. SHE. This research presents a methodology for predicting apparent electrocatalytic performance from microscopic reaction energy calculations, which can be applied to other important electrocatalytic reaction mechanisms and performance predictions.

Thermodynamic and exergo-economic evaluation of biomass-to-X system combined the chemical looping gasification and proton exchange membrane fuel cell

The resource utilization of biomass is of great significance to the adjustment of energy structure. The syngas produced by biomass gasification can be used for power generation and production of green chemical raw materials. In this paper, a biomass-to-X (BtX) system based on the chemical looping gasification and high temperature proton exchange membrane fuel cell (PEMFC) is proposed to produce methanol, electricity, heating and cooling. The heat produced by the BtX system is harnessed for the regeneration of the carbon capture solution, as well as to drive both the organic Rankine cycle and the double-effect absorption chiller, enabling cascade utilization of the energy. The thermodynamic and exergo-economic models are carried out to evaluate system performance. The relationship between the material, energy and cost flow from biomass to products is analyzed. Finally, the influence of key parameters on system performance is studied. The results show that the energy efficiency of the BtX system is 54.0 % and the exergy efficiency is 35.4 %. The yield rate of methanol with 99.2 wt% purity is 6.48 tons/h. The cost of equipment, propanol and biomass accounts for 34.9 %, 28.9 % and 28.1 % of the total investment cost, respectively, while the cost of the PEMFC stack represents 50.4 % of the equipment costs. The unit exergy cost of the electricity and methanol are 0.068 $/kWh and 0.049 $/kWh, respectively. The methanol, carbon capture and cooling costs are most sensitive to the change in the propanol cost, followed by the biomass cost. For every 0.05 increase in the hydrogen fraction to methanol production, the electricity decreases by 3.1 MW and the methanol yield increases by 0.23 kg/s.

Electrolysis of low-carbon methanol for point-of-use hydrogen generation: Opportunities and challenges for the direct use of unrefined feedstocks

Low-carbon methanol (LCM) is a promising hydrogen carrier that can reduce the overall transportation and storage costs associated with the industrial use of H2 as a chemical feedstock or fuel. Herein, LCM refers to methanol produced via processes that emit lower greenhouse gases (by 90% or more) relative to conventional methanol production derived from fossil fuels like pipelined natural gas or coal. LCM production pathways can valorize stranded methane as well as from sources such as biomass and biogas (e.g., landfill and digester gases). The distributed nature of these stranded feedstocks lends themselves well to methanol synthesis within a smaller-scale, decentralized infrastructure. While process intensification and relatively cheaper feedstock can support these distributed productions, forgoing economies of scale can significantly increase the cost of conventional upgrading steps such as distillation. Fortunately, these upgrading steps may be unnecessary by targeting specific applications, where high methanol purities are not required, thereby lowering the holistic cost and carbon intensity of an overall process.Here, we consider methanol as a hydrogen carrier and its conversion to H2 at the point of use through an electrolytic process by experimentally comparing the oxidation of methanol, of varying purity levels (e.g., grade (99.9+% purity) and crude forms) using a proton exchange membrane (PEM) electrolyzer. In this study, the supply of crude methanol derives from a distributed gas-to-liquid process, developed by M2X Energy Inc. The impurity content is speciated and quantified within the crude methanol sample, which is used directly with water co-reactants to evaluate the effect of impurity type and concentration on electrolytic performance on commercial Pt–Ru catalysts. Our experimental results show that about 1 wt% of C2–C5 alcohols in the starting crude methanol readily poison the catalyst, leading to an increased electricity consumption by 5.1–9.8 kWh per kg H2 produced when operating the electrolyzer at high current densities (>200 mA cm−2). A sensitivity analysis is developed according to the measured energy penalty, which can be used to decide whether bypassing methanol distillation provides economic benefit based on site-specific electricity and distillation costs.

Considering Embodied Greenhouse Emissions of Nuclear and Renewable Power Plants for Electrolytic Hydrogen and Its Use for Synthetic Ammonia, Methanol, Fischer-Tropsch Fuel Production.

Recent concerns surrounding climate change and the contribution of fossil fuels to greenhouse gas (GHG) emissions have sparked interest and advancements in renewable energy sources including wind, solar, and hydroelectricity. These energy sources, often referred to as "clean energy", generate no operational onsite GHG emissions. They also offer the potential for clean hydrogen production through water electrolysis, presenting a viable solution to create an environmentally friendly alternative energy carrier with the potential to decarbonize industrial processes reliant on hydrogen. To conduct a full life cycle analysis, it is crucial to account for the embodied emissions associated with renewable and nuclear power generation plants as they can significantly impact the GHG emissions linked to hydrogen production and its derived products. In this work, we conducted a comprehensive analysis of the embodied emissions associated with solar photovoltaic (PV), wind, hydro, and nuclear electricity. We investigated the implications of including plant-embodied emissions in the overall emission estimates of electrolysis hydrogen production and subsequently on the production of synthetic ammonia, methanol, and Fischer-Tropsch (FT) fuels. Results show that average embodied GHG emissions of solar PV, wind, hydro, and nuclear electricity generation in the United States (U.S.) were estimated to be 37, 9.8, 7.2, and 0.3 g CO2 e/kWh, respectively. Life cycle GHG emissions of electrolytic hydrogen produced from solar PV, wind, and hydroelectricity were estimated as 2.1, 0.6, and 0.4 kg of CO2 e/kg of H2, respectively, in contrast to the zero-emissions often used when the embodied emissions in their construction were excluded. Average life cycle emission estimates (CO2 e/kg) of synthetic ammonia, methanol, and FT-fuel from solar PV electricity are increased by 5.5, 16, and 49 times, respectively, compared to the case when embodied emissions are excluded. This change also depends on the local irradiance for solar power, which can result in a further increase of GHG emissions by 35-41% in areas of low irradiance or reduce GHG emissions by 21-25% in areas with higher irradiance.

CH4 and CO2 Reductions from Methanol Production Using Municipal Solid Waste Gasification with Hydrogen Enhancement

This study evaluates the greenhouse gas (GHG) impacts of converting municipal solid waste (MSW) into methanol, focusing on both landfill methane (CH4) emission avoidance and the provision of cleaner liquid fuels with lower carbon intensity. We conduct a life cycle assessment (LCA) to assess potential GHG reductions from MSW gasification to methanol, enhanced with hydrogen produced via natural gas pyrolysis or water electrolysis. Hydrogen enhancement effectively doubles the methanol yield from a given amount of MSW. Special attention is given to hydrogen production through natural gas pyrolysis due to its potential for lower-cost hydrogen and reduced reliance on renewable electricity compared to electrolytic hydrogen. Our analysis uses a case study of methanol production from an oxygen-fired entrained flow gasifier fed with refuse-derived fuel (RDF) simulated in Aspen HYSYS. The LCA incorporates the significant impact of landfill methane avoidance, particularly when considering the 20-year global warming potential (GWP). Based on the LCA, the process has illustrative net GHG emissions of 183 and 709 kgCO2e/t MeOH using renewable electricity for electrolytic hydrogen and pyrolytic hydrogen, respectively, for the 100-year GWP. The net GHG emissions using 20-year GWP are −1222 and −434 kgCO2e/t MeOH, respectively. Additionally, we analyze the sensitivity of net GHG emissions to varying levels of fugitive methane emissions.

DEVELOPMENT OF AN ENERGY-SAVING TECHNOLOGY FOR THE PRODUCTION OF SYNTHETIC METHANE FROM CARBON DIOXIDE. 1. RESEARCH OF KINETICS AND MACRO-KINETICS OF THE SABATIER REACTION ON MODIFICATIONS OF THE SERIAL NI/Α-AL2O3 CATALYST GIAP-3-6N

This study presents the results of laboratory research of kinetics and mechanisms of heterogeneous catalytic reactions of hydrogenation of carbon dioxide to carbon monoxide and methane through the Sabatier reaction on modifications of the serial Ni/α-Al2O3 catalyst GIAP-3-6N manufactured in Ukraine. The research was carried out on a laboratory bench using a classic glass gradientless reactor with internal piston stirring, which provides kinetic equations at the level of physicochemical constants of the reactions under consideration. A detailed analysis and review of the literature in the areas of kinetic research of our interest was carried out. A detailed comparison of the kinetic parameters obtained by us for the powder (kinetic) form of contact with a nickel content of 7.5 % (NiO = 7.5 %) with a similar and one of the best foreign analogs containing nickel, Katalco 57-4 (NiO = 15−18 %), produced by the British chemical and metallurgical company Johnson Matthey, was performed. The results of the research confirmed almost equal parameters of the kinetic activity of the compared catalysts in the reactions of hydrogenation of carbon dioxide with hydrogen, including the «Sabatier» reaction, which made it possible to propose a similar mechanism of the processes, calculate the reaction rate constants and their activation energy, propose (determine) kinetic equations for design of reactors and processes, both with the loading of a domestic catalyst and its replacement with a foreign analog. Kinetic equations will be used in the development of multi-ton synthesis gas plants for the production of methanol, ammonia, and synthetic methane, as well as carbon-free e-fuel for internal combustion engines that meet modern climate requirements. Bibl. 28, Fig. 4, Tab. 6.

Red mud enhanced biomass gasification to produce syngas: Mechanism, simulation and economic evaluation

Red mud (RM) has the potential to balance catalytic activity and recycling stability. To achieve the efficient utilization of RM, this study systematically explores the RM potential as the catalyst in biomass gasification through three aspects: catalytic experiment, simulation of biomass gasification coupled with solid oxide electrolysis cells for methanol and economic analysis. The catalytic experimental results indicate that RM has a positive effect on the biomass gasification, with a gas yield of 615.9 ml/gbiomass, representing an increment of 40.9 %. Fe2O3 and Al2O3 are the main catalytic components in RM. The simulation results on biomass gasification coupled with SOEC for methanol show that RM has increased the methanol yield to 381.83 kg/tonBiomass, with an increase of 23.9 %. The economic analysis indicates that the RM can reduce the methanol production cost, demonstrating a promising application prospect. This paper providing strong support for RM high-value synergistic utilization.

Solar methanol production from carbon dioxide and water using NaA zeolitic membrane reactor with pressurized solid oxide electrolysis cell

Solar-driven methanol synthesis coupled with water electrolysis can achieve carbon-negative methanol production. In this study, a solar methanol production system using water-conduction membrane reactor coupled with pressurized solid oxide electrolysis cell is proposed. A methanol synthesis membrane reactor model and a solar-driven pressurized solid oxide electrolysis cell model are developed and validated. Under the specified conditions, the conversion efficiency of the membrane reactor is found to be twice as high as that of a conventional reactor. A thermodynamic model is developed to simulate the system's performance. Using this model, the energy flows within the system are visually represented through a Sankey diagram, providing a clear illustration of energy distribution and losses. Additionally, effects of the solid oxide electrolysis cell temperature, current density, methanol synthesis temperature and pressure on the system performance are investigated parametrically. An optimum solar-to-methanol efficiency of 7.3 % is obtained. Furthermore, the economic analysis shows the levelized cost of methanol close to 1.40 Euro/kg and the payback period is around 4.5 years. This study proposed a novel efficient solar methanol production system.

Predicting Methanol Space-Time Yield from CO? Hydrogenation Using Machine Learning: Statistical Evaluation of Penalized Regression Techniques

This study investigates the effectiveness of machine learning techniques, specifically penalized regression models Ridge Regression, Lasso Regression, and Elastic Net Regression in predicting methanol space-time yield (STY) from CO? hydrogenation data. Using a dataset derived from Cu-based catalyst research, the study implemented a comprehensive preprocessing approach, including data cleaning, imputation, outlier removal, and normalization. The models were rigorously evaluated through 10-fold cross-validation and tested on unseen data. Ridge Regression outperformed the other models, achieving the lowest Root Mean Squared Error (RMSE) of 0.7706, Mean Absolute Error (MAE) of 0.5627, and Mean Squared Error (MSE) of 0.5938. In comparison, Lasso and Elastic Net Regression models exhibited higher error metrics. Feature importance analysis revealed that Gas Hourly Space Velocity (GHSV) and Molar Masses of Support significantly influence catalytic activity. These findings suggest that Ridge Regression is a promising tool for accurately predicting methanol production, providing valuable insights for optimizing catalytic processes and advancing sustainable practices in chemical engineering.

Synthesis of isolated ZnO nanorods on introducing g-C3N4 for improved photoelectrocatalytic methanol production by CO2 reduction

The photoelectrocatalytic (PEC) CO2 reduction into fuels has been developed as a prospective approach to resolve the environmental and energy concerns. Herein, a composite catalyst comprising ZnO nanorods dispersed on the g-C3N4 surface (g-C3N4/ZnO) was successfully obtained by simple ZnO seed layer formation and then hydrothermal processes. The synthesized and characterized g-C3N4/ZnO catalytic composite showed 2.8 times enhanced photocurrent density at −1 V applied potential than the bare g-C3N4. The g-C3N4/ZnO catalyst exhibited 2.86 times enhanced the PEC CO2 reduction to methanol than the prepared bare ZnO catalyst. The catalyst’s enhanced the PEC CO2 reduction performance was ascribed to the high surface area, and higher generation and lower recombination of e−/h+ pairs. For the first time, this study showed the enhanced methanol production by the PEC reduction of CO2 over the prepared g-C3N4/ZnO catalytic composite.

The prospect of methanol-fuel heating in northern China

A heating season lasts 4–6 months each year across the northern 18 provinces of China. During this period, the combustion of various fuels for heating contributes to severe air pollution. Several clean energy heating methods, such as “coal-to-electricity” and “coal-to-gas,” have been promoted. However, these approaches may not be feasible in all areas. Therefore, it is necessary to conduct a comprehensive assessment of methanol fuel to determine its viability for widespread adoption. This study aims to analyze the life cycle of methanol as a clean heating fuel in northern China, considering its environmental, economic, and energy aspects. Additionally, a decision model utilizing multi-criteria decision analysis is developed to evaluate the potential of adopting methanol for heating in northern China. The findings demonstrate that the provinces of Shandong, Liaoning, and Heilongjiang are suitable for prioritizing the promotion of methanol usage in centralized heating systems. Based on scenario analysis, it is recommended that China expands the deployment of biomass-to-methanol for clean heating in certain areas. Furthermore, if advancements are made in methanol production from CO2 after achieving carbon neutrality, it should be considered for clean heating.

Design and analysis of negative CO2 emission methanol synthesis process incorporating green hydrogen and blue hydrogen

Methanol (MeOH) production by integration of green and blue hydrogen is evaluated herein. From 2018 to 2023, methanol demand increased by 3.6 % due to its use in various chemical industries as an eco-friendly fuel and as a method of transporting hydrogen and capturing renewable CO2. Moreover, due to the continual decrease in the cost of renewable energy, research into the use of green hydrogen from electrolysis is being conducted. Most of this research has focused on producing methanol from the green hydrogen obtained from proton-exchange membrane (PEM) electrolysis along with CO2 emissions from power plants. The present study examines processes based on oxyfuel combustion with oxygen obtained from either the PEM or an air separation unit (ASU) to produce methanol. By using oxyfuel combustion, the carbon capture process (which accounts for 30–50 % of the blue hydrogen cost) and pure (>98.75 %) 7.45 tCO2/tH2 can be obtained by separating H2O from the flue gas. By using the PEM, green hydrogen can capture 0.35 tCO2/tMeOH of external CO2. Furthermore, a carbon techno-economic analysis (CTEA) and a sensitivity analysis are conducted to evaluate the sustainability and feasibility of the proposed processes. As a result, the levelized cost of methanol (LCOM) is $373.91/tMeOH for the Blue process and $428.78/tMeOH for the Blue + Green process, each of which is below the current market price of $500/tMeOH. If the PEM price continues to decrease, and the carbon credit increases by €300/tCO2, after 2030, the Blue + Green process will become more lucrative than the Blue-only process. Thus, by considering the continuous decrease in renewable energy prices, the production of methanol via a hybrid Blue + Green process is suitable for a sustainable future.

Deciphering electrochemical methanol production

Deciphering electrochemical methanol production

Multi-variable optimization of a geothermal power plant integrated with water electrolyzer and methanol production

Renewable energy-based routes for methanol generation are recognized as essential strategies for eco-friendly energy conversion. Thus, the current study focuses on developing an innovative combined energy system for methanol production using direct carbon dioxide hydrogenation powered by geothermal energy. This is important because it addresses the need for sustainable and environmentally friendly methods of methanol production while also harnessing the potential of geothermal energy as a renewable resource. Therefore, in order to achieve multigeneration energy production, this work introduces and optimizes a novel configuration that benefits from an innovative heat design process. This configuration integrates an organic Rankine cycle, a single-flash geothermal power plant, an ammonia-water absorption chiller, a proton exchange membrane electrolyzer, and a methanol generation unit. Using the Aspen HYSYS tool, the multigeneration energy system is modeled and analyzed. As a result, the system is assessed using energy, exergetic, environmental, and economic evaluations. Furthermore, performance evaluations are carried out in the following modes: single generation, multigeneration, cooling, heat and power generation, and cooling. Furthermore, a genetic algorithm is employed to optimize the system in terms of economy and exergy. The energy and exergy efficiency are determined to be 32.57 % and 76.3 %, respectively, under the base case results. Furthermore, the rate of overall costs is 377.38 $/h. Furthermore, the precise output of carbon dioxide is −0.043 kg/kWh. The optimal unit cost and exergy efficiency for all items, taking into account the optimization scenario, are 3.34/GJ and 78.35 %, respectively. In addition, the optimum carbon dioxide and hydrogen rates for methanol generation are 92.49 mol/h and 200.51 mol/h, respectively.

Life cycle and techno-economic analyses of biofuels production via anaerobic digestion and amine scrubbing CO2 capture

The global energy landscape highlights the importance of the hydrogen economy, emphasizing its critical role in worldwide energy policies. This study explores a system designed for producing biomethanol and biomethane by integrating anaerobic digestion, biogas upgrading, and high-temperature electrolysis. The system builds on real-scale industrial data from an existing anaerobic digestion plant, which has been expanded to include biogas upgrading, an oxy-fuel gas turbine, a Solid Oxide Electrolysis Cell (SOEC), and a methanol production unit. Hydrogen, generated through electrolysis, synthesizes biomethanol by reacting with CO2. Additionally, the system produces biomethane through biogas upgrading. The system incorporates thermal energy integration with an oxy-fuel gas turbine. Life cycle assessment (LCA) results demonstrate the system’s environmental potential, achieved negative CO2 emissions of −0.0075 kgCO2eq/kgBiomass in case of photovoltaic panels and −0.0096 kgCO2eq/kgBiomass in case of wind turbines as electricity sources, attributed to efficient conversion of sewage sludge into valuable biofuels. Thermodynamic modeling in Aspen Plus shows an energy efficiency of 58.09 %, with outputs of 188 kg/h of biomethane and 269 kg/h of biomethanol. The techno-economic analysis reveals a payback period of 6.11 years and a levelized cost of biomethanol of 294.37 € per ton, indicating the system’s economic viability. The LCA further underscores the system’s sustainability, supporting its environmental benefits. This comprehensive analysis provides valuable insights into the viability and environmental impact of the proposed biofuel production system.