Experimental Study On Catalytic Pyrolysis Of Biomass

To solve the problem caused by energy crisis and environmental pollution, the exploitation and utilization of biomass energy has been paid more attention. The biomass pyrolysis is regarded as a significant technology. It was not only an essential step in biomass gasification and combustion, but also an independent technology to gain high energy density products. So research on biomass pyrolysis is good for enhancing the capability of utilization of biomass energy in our country.The thermal pyrolysis characteristics of two biomass samples, rice hulls and corn stalk are investigated by thermal analysis technique at different heating rates under N2 atmosphere. The influences of heating ratio, biomass composition and catalysts on the process of biomass pyrolysis are studied. The results show that the pyrolysis characteristics of different biomass are different. TGA and DrTGA curves all move to higher temperature ranges and the temperature at the maximum weight loss rate is higher with increasing heating rate. Catalyst can affect the starting temperature and the ending temperature and the temperature at the maximum weight loss rate of pyrolysis. The pyrolysis reaction can be described by the one-order kinetics at their main reaction temperatures.The factors which include the temperatures between 700℃and 900℃and the catalyst with DHC-32 and CaCl2 are studied on the yield of pyrolysis production and the composition of pyrolysis gas from rice husk pyrolysis in the tube furnace under high-purity N2 as a carrying gas. The studies results show that the solid production and the liguid production are reduced with the temperature of pyrolysis increasing, while the gas production is increased at a higher rate. The concentration of H2 in the pyrolysis gas rapidly increases as the pyrolysis temperature increasing, and the concentration of CO increases slowly, and the concentration of CH4 decreases slowly, while the concentration of CO2 decreases rapidly. The solid production of rice husk pyrolysis is lower with adding little catalyst than that no catalyst added. There is more solid production of rice husk pyrolysis when adding more catalyst. Both DHC-32 and CaCl2 can increase the concentration of H2 and CH4 and CO, while decreasding the the concentration of CO2.