Experimental Study On Pyrolysis And Fluorine, Chlorine Migrate Of Biomass

Currently, agriculture and forest wastes as renewable clean energy are attracting increasing attention with, low dust and low sulphur content. In China, there are abundant and variant straw resources. It shows a promising future of biomass utilization technology. In modern society, the environmental protection was payed close attention, while fluorine and chlorine are very easy to devolatile during biomass pyrolysis. Pyrolysis, as the most important stage of combustion and gasification, confirmed the microelement quantity and form. To utilizing them high-efficiently, and control fluorine, chlorine disposal of pollutants ,this paper regard wheat stalk, rice husk, saw-dust three kinds of biomass as target, analyze their pyrolysis react and fluorine, chlorine migration.Through TG analysis obtains the different pyrolysis characteristic and dynamics parameter of biomass, and carry on the verification of the model accuracy. Take on experiment research on the pyrolysis characteristic of biomass, explore the char, gas, and tar characteristics. Adopt the divide shape theory and the environment electric mirror, and study the hole structure of the char. Biomass is mainly volatilize, at low temperature char skeleton not destroyed, hole developed fast, The outside area of 800℃char is mainly smooth, flaky silicide, the inside is the narrow and long groove shape carbide, which the pyrolysis take place mainly, the carbide decomposes make the hole become great, furthermore help to react.Carry on experiment research the gasification characteristic of biomass, analyze the influence factor, which including conditions such as gasification medium, temperature etc, and gas calorific value. The steam gasification gas composition is H₂ mainly, it is the highest calorific value. CO₂ gasification gas composition is CO mainly, the higher temperature helps the production of CO more.To compare the oxygen bottle burning and the high temperature burning hydrolyze, the deviation is small. The content of F in biomass is about 30 mg/kg, Cl is about 2000 mg/kg. Fluorine, chlorine volatilize are divided into fast volatilized and slow section, fluorine main volatilize in the range of 200-600℃, chlorine is 200-400℃separately. Low temperature section as the form of HF, HCl gas, high temperature are volatilized in the form of fluorine salt and chlorine salt gaseous state mainly. The fluorine, chlorine element in the biomass are distributed among coke and gas mainly, with pyrolysis temperature rise, transfer from the coke into the gas, the amount of fluorine, chlorine include in the tar does not change much.