Experimental Study On Co - Gasification Of Biomass And Coal

As a clean and renewable energy, biomass is an important approach to alleviate energy shortage and environmental issues for the widely utilization. Biomass gasification technology was the point during recently study. There were still many issues to be research on direct gasification because of the characteristic of low energy density, high oxygen content and low ash melting point. This paper carried out a series of experimental studies base on biomass two-step gasification technology, focused on the feasibility of blending coal gasification in order to figure out a range of problem of direct gasification of biomass.The kinetics of biomass pyrolysis carbonization reaction has been studied by using the homemade thermogravimetry experiment platform. The reaction rate and mass yield were contrasted under different temperatures. Moreover, we have studied the characteristic of carbonized products, emphatically discussed the influence of carbonization temperature on the products by the industrial analysis and elemental analysis. Finally, it can be concluded that the suitable carbonized temperature is 400～600℃ for the purpose of achieving high energy density fuel based on the pyrolysis carbonization properties under different temperature.It is very important to design biomass gasification distribution by the research of kinetics characteristics on the biomass char gasification. Therefore, biomass char carbon dioxide gasification experiments have been made in different pyrolysis conditions on the lab-scale thermogravimetry experiment platform. Different proportions of pulverized coal added in the sample to investigate the gasification reactivity changes of the mixed material. It can be found that the biomass pyrolysis carbonization conditions mainly affected the biomass char gasification when volatile pyrolytic reaction characteristics of precipitation phase, less effect on the reduction phase reactive. The amount of biomass carbon volatiles have been restrained outstanding by adding the coal. Thus in the CO2 reduction stage, it has not been reduced the gasification activity by adding the coal into the material, but presented the trend of activation energy decrease. It can be concluded that the pyrolysis carbonization temperature caused little impact to the gasification activities of biomass char, the gasification activity of biomass char can be improved by adding the coal obviously.For the further study of the biomass char and the mixed materials of biomass char and coal, many researches have been done on the small fluidized bed experimental platform and high temperature air bed successively. The gas from the gasification by biomass char and mixed materials were analyzed, and the influence by temperature and the ratio of coal to the component and characteristic of the gasification were studied at the same time. It was found that no matter biomass char or the mixed materials in the temperature range of 1000～1200℃, the quality of the gas production can be improved by rising temperature, the quality of gas production and carbon conversion efficiency can be improved when the coal ratio in the mixed materials under 10%. It can be concluded that the addition of coal can improve the quality and the conversion ratio of gas products.