Hydrogen is an emerging renewable energy source that plays a crucial role in the transition toward reducing carbon emissions.Despite growing global demand,green hydrogen,produced via water electrolysis using renewable...Hydrogen is an emerging renewable energy source that plays a crucial role in the transition toward reducing carbon emissions.Despite growing global demand,green hydrogen,produced via water electrolysis using renewable energy,accounts for only 0.1%of total hydrogen output.This study investigates green hydrogen production via proton exchange membrane(PEM)electrolysis using both energy and feedwater sourced from the Musi Hydropower Plant in Indonesia.A 2 MW PEM electrolyzer system was modeled in Aspen Plus,while a water treatment system combining ultrafiltration and reverse osmosis was simulated using WAVE software to ensure water quality compliance standards for PEM electrolysis.The simulation results show that the PEM system can produce 32.98 kg/h of hydrogen,with an estimated annual production of 480983.6 kg across three electrolyzers.The ultrafiltration-reverse osmosis system effectively reduced water conductivity from 110μS/cm to 0μS/cm,achieving the required purity for electrolysis.The total capital expenditure for the system is$7.16 million,and the annual operational expenditure is$2.18 million.The levelized cost of hydrogen is calculated at$7.8/kg,primarily influenced by electricity consumption costs and the initial investment required for the electrolyzer stack and balance of plant.展开更多
A total of 37.5 million tons of palm empty fruit bunches(EFBs)produced in Indonesia in 2018 have the potential to be used as an alternative eco-friendly solid fuel.However,a pretreatment process is necessary to increa...A total of 37.5 million tons of palm empty fruit bunches(EFBs)produced in Indonesia in 2018 have the potential to be used as an alternative eco-friendly solid fuel.However,a pretreatment process is necessary to increase the heating value and reduce the po-tassium content of EFBs.Several methods can be employed to improve the characteristics of EFBs as a solid fuel,such as drying and torrefaction to increase the heating value and the leaching process for reducing the potassium content of EFBs.The main concept of increasing the heating value is to increase the fuel content,which is carbon.Through drying,the carbon ratio can be increased by reducing the moisture content and,through torrefaction,the carbon ratio could be increased due to the decomposition of ligno-cellulose.A simple way to reduce the potassium content of EFBs is the leaching process.Two types of leaching treatment have been studied before:soaking and stirring treatment.This study reviews those methods to make EFBs more suitable as a solid fuel with a high heating value and less potassium content.Increasing the carbon content in EFBs is crucial for enhancing their heating value as a fuel.Drying and torrefaction decrease the moisture content and modify the chemical structure,resulting in higher carbon ratios.The leaching process effectively reduces the potassium content of EFBs and stirring treatment is more effective than immersion treat-ment.Torrefaction positively affects leaching by decreasing the potassium content,while hydrophobicity may hinder leaching by re-pelling water.The high moisture content of leached EFBs requires additional energy for evaporation during torrefaction,resulting in a lower energy density yield compared with raw EFBs.Adjustments may also be required to account for the decreased mineral content,which functions as a torrefaction catalyst in EFBs that have not been leached.展开更多
We study the carbon dioxide reduction reaction(CO_(2)RR)activity and selectivity of Fe single-atom catalyst(Fe-SAC)and Fe dual-atom catalyst(Fe-DAC)active sites at the interior of graphene and the edges of graphitic n...We study the carbon dioxide reduction reaction(CO_(2)RR)activity and selectivity of Fe single-atom catalyst(Fe-SAC)and Fe dual-atom catalyst(Fe-DAC)active sites at the interior of graphene and the edges of graphitic nanopore by using a combination of DFT calculations and microkinetic simulations.The trend of limiting potentials for CO_(2)RR to produce CO can be described by using either the adsorption energy of COOH,CO,or their combination.CO_(2)RR process with reasonable reaction rates can be achieved only on the active site configurations with weak tendencies toward CO poisoning.The efficiency of CO_(2)RR on a catalyst depends on its ability to suppress the parasitic hydrogen evolution reaction(HER),which is directly related to the behavior of H adsorption on the catalyst’s active site.We find that the edges of the graphitic nanopore can act as potential adsorption sites for an H atom,and in some cases,the edge site can bind the H atom much stronger than the main Fe site.The linear scaling between CO and H adsorptions is broken if this condition is met.This condition also allows some edge active site configurations to have their CO_(2)RR limiting potential lower than the HER process favoring CO production over H2 production.展开更多
文摘Hydrogen is an emerging renewable energy source that plays a crucial role in the transition toward reducing carbon emissions.Despite growing global demand,green hydrogen,produced via water electrolysis using renewable energy,accounts for only 0.1%of total hydrogen output.This study investigates green hydrogen production via proton exchange membrane(PEM)electrolysis using both energy and feedwater sourced from the Musi Hydropower Plant in Indonesia.A 2 MW PEM electrolyzer system was modeled in Aspen Plus,while a water treatment system combining ultrafiltration and reverse osmosis was simulated using WAVE software to ensure water quality compliance standards for PEM electrolysis.The simulation results show that the PEM system can produce 32.98 kg/h of hydrogen,with an estimated annual production of 480983.6 kg across three electrolyzers.The ultrafiltration-reverse osmosis system effectively reduced water conductivity from 110μS/cm to 0μS/cm,achieving the required purity for electrolysis.The total capital expenditure for the system is$7.16 million,and the annual operational expenditure is$2.18 million.The levelized cost of hydrogen is calculated at$7.8/kg,primarily influenced by electricity consumption costs and the initial investment required for the electrolyzer stack and balance of plant.
基金This study was supported financially by Institut Teknologi Bandung as part of the research,community service and innovation program(PPMI)2021.
文摘A total of 37.5 million tons of palm empty fruit bunches(EFBs)produced in Indonesia in 2018 have the potential to be used as an alternative eco-friendly solid fuel.However,a pretreatment process is necessary to increase the heating value and reduce the po-tassium content of EFBs.Several methods can be employed to improve the characteristics of EFBs as a solid fuel,such as drying and torrefaction to increase the heating value and the leaching process for reducing the potassium content of EFBs.The main concept of increasing the heating value is to increase the fuel content,which is carbon.Through drying,the carbon ratio can be increased by reducing the moisture content and,through torrefaction,the carbon ratio could be increased due to the decomposition of ligno-cellulose.A simple way to reduce the potassium content of EFBs is the leaching process.Two types of leaching treatment have been studied before:soaking and stirring treatment.This study reviews those methods to make EFBs more suitable as a solid fuel with a high heating value and less potassium content.Increasing the carbon content in EFBs is crucial for enhancing their heating value as a fuel.Drying and torrefaction decrease the moisture content and modify the chemical structure,resulting in higher carbon ratios.The leaching process effectively reduces the potassium content of EFBs and stirring treatment is more effective than immersion treat-ment.Torrefaction positively affects leaching by decreasing the potassium content,while hydrophobicity may hinder leaching by re-pelling water.The high moisture content of leached EFBs requires additional energy for evaporation during torrefaction,resulting in a lower energy density yield compared with raw EFBs.Adjustments may also be required to account for the decreased mineral content,which functions as a torrefaction catalyst in EFBs that have not been leached.
基金supported by the Ministry of Education,Culture,Research,and Technology of the Republic of Indonesia through the‘WCR 2022’program under contract number 007/E5/PG.02.00.PT/2022.
文摘We study the carbon dioxide reduction reaction(CO_(2)RR)activity and selectivity of Fe single-atom catalyst(Fe-SAC)and Fe dual-atom catalyst(Fe-DAC)active sites at the interior of graphene and the edges of graphitic nanopore by using a combination of DFT calculations and microkinetic simulations.The trend of limiting potentials for CO_(2)RR to produce CO can be described by using either the adsorption energy of COOH,CO,or their combination.CO_(2)RR process with reasonable reaction rates can be achieved only on the active site configurations with weak tendencies toward CO poisoning.The efficiency of CO_(2)RR on a catalyst depends on its ability to suppress the parasitic hydrogen evolution reaction(HER),which is directly related to the behavior of H adsorption on the catalyst’s active site.We find that the edges of the graphitic nanopore can act as potential adsorption sites for an H atom,and in some cases,the edge site can bind the H atom much stronger than the main Fe site.The linear scaling between CO and H adsorptions is broken if this condition is met.This condition also allows some edge active site configurations to have their CO_(2)RR limiting potential lower than the HER process favoring CO production over H2 production.
