Study On Briquette-fuel And Biomass Fast Pyrolysis

Energy infrastructure is fossil fuel in today's world which not only promotes the social development, but also contributes to global warming, air pollution and other serious environmental problems. Biomass energy, which is renewable and friendly to environment, constitutes the development direction of the third energy revolution with the solar energy,wind energy, etc. In this paper, the utilization and conversion of biomass energy involving briquetting fuel and fast pyrolysis was studied.Thermal efficiency, combustion temperature,flue gas emissions and others were test on biomass stoves which were selected all over the contury as representativses of different regions. The test provides a theoretical basis for in-depth understanding of usage and optimization of biomass stoves, and it also provides theoretical support of the further improvement of rural living environment. The result shows supplying sufficient diffusion-air, strengthening the insulation and stabling the flame can improve the thermal efficiency, and the stoves with plumbing functions should have the design of flue gas heating water. Ash physical heat loss and chemical incomplete burning heat loss in biomass stove can be ignored, while the flue gas heat losse is the most important aspect of its loss. The gasifier's heat loss is mainly physical incomplete combustion. Through the flue gas composition analysis, it shows biomass stoves produce large amounts of harmful gases in the combustion process, for instance the excess emission of CO is not only the pollution of the indoor environment, but also a great waste of fuel. Furthermore emission of NOX and SO2is a direct resaon of decline of indoor air quality in rural areas.Previous studies of biomass fast pyrolysis were mostly under N2atmosphere, however most of the pyrolysis application use pyrolysis gas as the carrier gas, which composes mainly of CO2, CO and CH4. Therefore, an in-depth study of the pyrolysis result under different atmosphere is required.In this paper, influence of two inert atmospheres, N2and CO2, on pyrolysis yields and oil products was studied. It shows changing the pyrolysis atmosphere has apparent influence on result. Carbon dioxide has a harmful influence on both fast and catalytic pyrolysis such as reducing the liquid yield and increasing the solid yield and coke on bed material. Moreover, it inhibits aromatic reaction and causes producing methoxy branched-chains and polycyclic aromatic hydrocarbon in pyrolysis procedure.