The Migration Patterns Of Chlorine And Alkali Metals (K And Na) In The Biomass Combustion

This paperAs the fossil fuels such as coal and oil is declining day by day and the combustion of fossil fuels exhausts a lot of harmful gases which seriously pollute the environment, biomass calls forth more and more social concern as a low-carbon and environmentally friendly new type of fuel. China is an agricultural country and generates a large number of biomass every year. If they cannot be used effectively, they will generate a large quantity of agricultural rubbish which will not only be pollution to the environment but also a waste of energy. So, the study and use of biomass have a great meaning to relieve the energy crisis and environment pressure, etc.Direct combustion of the processed biomass as the fuel of boilers is the most simple and economic way of biomass disposal. But the natural property of biomass including high Cl and alkali metals will always raise problems in the combustion such as corrosion, bed material agglomeration, slagging, etc. These problems become the main limitation in the Large-scale utilization of biomass energy.This paper studies the migration patterns of chlorine and alkali metals (K and Na) in the biomass combustion. Several common biomass fuels are chosen, including wheat straw, rice straw, cotton rod, corn stalks and rape bar, and combusted between 500℃~900℃. By XRF and XRD methods, the content changing of Cl, K and Na element with the temperature and the existing compound forms of these elements at different temperature in the ash or the escaping gas is also analyzed. At the same time, the influence of additives and other factors such as combustion time to the escaping law of these elements is also studied in this work, some possible solutions and methods are presented...