Basic Research On Conventional Pyrolysis And Microwave Pyrolysis Of Eupatorium Adenophorum

Biomass is one of the abundant renewable energy sources,and it is the 4th major energy after oil,coal and natural gas.Biomass energy has great potential in the future development process,and rational exploitation and utilization of biomass resources is of great significance for upgrading China's energy structure and energy security.Thermal conversion technology is the most effective way to utilize biomass at present.Catalytic pyrolysis is the most effective way to change the distribution and performance of biomass products.In this paper,the basic research on the pyrolysis of Eupatorium purpurea by conventional pyrolysis and microwave pyrolysis was carried out,and the effects of pyrolysis temperature,pyrolysis time,heating rate and nitrogen flow rate on the distribution of pyrolysis products were investigated.Using NaCl?Zn O?KOH and Na₂CO₃ as additives,the effects of four additives on pyrolysis products and properties were investigated.The main research contents and results are as follows:?1?In the pyrolysis of conventional resistance tube furnace,the optimum conditions were determined as the pyrolysis temperature 600?,holding time 50 min,heating rate 20?/min,and nitrogen flow rate 200 m L/min.In the pyrolysis of microvawe tubular furnace,the optimum conditions were determined as the pyrolysis temperature of 500?,the holding time of 60 min and the nitrogen flow rate of 300 m L/min.?2?The main components of the pyrolysis gas are H₂,CO,CH₄ and CO₂.In conventional pyrolysis,the calorific value of gas under optimized process conditions is 17.88 MJ/Nm³.In microwave pyrolysis,the gas heat value under optimized process conditions is 15.20 MJ/Nm³.?3?The addition of additives has a great influence on the composition of liquid products,and the organic components with more content are hydrocarbons,alcohols,aldehydes and phenols.Hydrocarbon organic compounds are mainly aromatics with benzene ring,and aldehyde organic compounds are mainly furfural,and phenols are mainly composed of phenols,alkylphenols and methoxyphenols.Each additive will be enriched with different components,and under different pyrolysis ways,the addition of additives will enrich a certain component.?4?Compared with the two pyrolysis methods,microwave pyrolysis is advantageous to the formation of gas products,while conventional pyrolysis is advantageous to the formation of liquid products.?5?Microwave pyrolysis produces more H₂ and less CH₄.After adding catalyst,microwave pyrolysis produces more CO,but the content of H₂?CH₄ and CO₂decreases.Conventional pyrolysis is more favorable to the pyrolysis of lignin,after adding the catalyst,conventional pyrolysis produces more H₂.?6?Compared with conventional pyrolysis,microwave pyrolysis improves the specific surface area of biochar,and it is more favorable to the formation of micropores in biochar,while conventional pyrolysis is more favorable to the formation of mesoporous biochar.