Production And Energy Saving Process Of Hydrogen Production From Biomass Based On Methane Tri-reforming

Hydrogen energy is renewable,pollution-free and has become the most potential energy carrier.Due to the energy structure of rich coal,little oil and short gas in China,coal-to-hydrogen?CTH?has become an important way to effectively alleviate the contradiction between supply and demand of hydrogen.The use of fossil energy has contributed to enormous environmental problems,which drive the development of potential hydrogen-production processes.Biomass is a promising renewable energy and an attractive resource for producing hydrogen and may address some of these environmental problems.In this work,the simulation results of the biomass--to-hydrogen?BTH?and CTH processes were validated using available experimental data from the literature.Based on the simulation results,a techno-economic analysis was conducted from the viewpoints of the first and second laws of thermodynamics.The techno-economic analysis included energy efficiency,material consumption,total capital investment,production cost and carbon tax.The energy efficiencies of BTH and CTH were 37.88%and 37.82%,respectively.The BTH process had a larger raw material consumption and total capital investment?TCI?than the CTH process.The BTH process had lower production cost and GHG emissions than the CTH process.The energy analyses of the BTH and CTH processes showed that as the core part of the process,the operation performance of gasification device seriously restricts the energy utilization rate of the process.In this work,the energy consumption GHG emissions of CTH and BTH processes are analyzed by the method of life cycle analysis.The results show that the EC of the BTH process is 75.4%lower than the corresponding value of CTH process.GHG emissions of BTH process are 89.6%lower than corresponding values of CTH process.In addition,sensitivity analysis shows that pipeline transport is the most environmentally friendly transport mode.Gasification temperature is in the range of 1400?1500?,the system achieves the highest energy efficiency and the lowest GHG emissions.Aiming at the problem of CO₂ emission in biomass hydrogen production process,a BTH process model with CO₂ capture and storage?CCS?was designed.Compared with the BTH process without CCS,the total investment cost of the BTH process with CCS increased by 1.3%,and the production cost increased by 14.6?19.4%.The energy efficiency of BTH without CCS is 17%higher than that of BTH with CCS.From the perspective of energy consumption,economy and environmental protection,BTH with80%CO₂ capture rate is a more suitable CCS system for CO₂ capture.In view of the large amount of methane contained in the syngas,this study designed the BTH process with the methane tri-reforming process.Compared with BTH without methane tri-reforming,the total capital investment of BTH with methane tri-reforming is increased by 10.97%,and the production cost is reduced by 10.12%.The energy consumption and greenhouse gas emission of BTH without methane tri-reforming are 3.09%and 7.85%lower than those with methane tri-reforming.The life cycle analysis of BTH process shows that under the consideration of natural carbon cycle,both the BTH process with CCS system and the BTH process with methane tri-reforming can achieve the negative emission of CO₂.The above research is of great significance to reduce GHG emissions,improve environmental performance,and develop clean and sustainable BTH process.