Study on combustion characteristics of biomass and coal

Abstract

Co-combustion biomass and coal is a kind of new combustion technology to reduce pollutants emission and synthetically utilize biomass and coal energy sources. The combustion of blended coals is an extremely complex physical and chemical process. During the combustion of the blended fuels, the fuels component affect and restrict each other, so the combustion characteristics of blended fuels are different from the single fuel. There are more factors that can affect the combustion of blended fuels than the single fuel. Among these factors the ration of the fuels component is the most important one. In this paper, Pyris 1TGA thermobalance analyzer was used to research the combustion characteristics of coal (Qitaihe-coal) and biomass (corn straw) and their blends. The combustion experiment includes different mass ratio of the experiment under the same temperature increasing velocity and different temperature increasing velocity of the experiment under the same mass ratio. Combustion characteristics of biomass, coal and their blends are studied by TG-DTG method under air atmosphere. Through the detailed analysis of TG-DTG curves of different samples, the difference of the combustion characteristics among biomass, coal and their blends is disclosed on the aspects such as the temperature increasing velocity and ratio. The experiment results show that the blended sample has a higher activation performance, a lower ignition temperature and a better burnout property than those of the single coal. The coal and biomass keep their own volatilization characteristics basically in co-combustion process and the combustion behavior of coal is more obvious. At last the reaction mechanism of coal, biomass and their blend is analyzed. The reaction kinetics model is established, and the parameters of reaction kinetics are calculated.