生物质快速热解及水蒸气气化实验研究

Experimental Study on Rapid Pyrolysis of Biomass and Steam Gasification

对生物质气流床气化过程进行了小型台架实验研究,建立生物质气流床气化小型实验台架,进行生物质快速热解和水蒸气气化的实验,实验表明:温度提高有利于提高产品气的产率、气化过程的碳转化率和气化效率,但温度过高会促进CH_4的重整反应、水气变化反应、降低CO、甲烷含量,从而影响产品气热值。粒径对气化结果有着一定影响,粒径对气化结果的影响主要体现在固相内部升温速率和最终温度上,粒径越小,颗粒升温越快,能达到的最终温度越高。水蒸气气化过程中,适当的水蒸气的通入能大量提高产气中的H_2、CO的占比,提高碳转化率和H_2/CO的比值,碳转化率在S/B比为1.4时达到最大值96%,此时气化效率也高达94%,水蒸气的通入过量会导致炉内温度下降,各项评价指标均开始下降,降低燃气品质。

This paper studies the test characteristics of biomass gasification for small experimental entrained flow bed equipment based on the national science and technology support project integration and demonstration of new mobile fixed bed to generate high-quality biogas. Estab-lish the small experimental entrained flow bed of biomass gasification and take the experiments about rapid pyrolysis of biomass and steam vaporization. Experiment show that the increase of temperature is beneficial to improving the yield of product gas , the carbon conversion rate and gasification efficiency of gasification process , but the temperature will promote CH 4 reforming reaction , water gas change reaction , reduction of CO , methane content , thus affecting calorie value product gas. Particle size also has some influence on the gasification results. The effect of particle size on the gasification results is mainly reflected the rate of temperature increase in the solid-phase interior and the final temperature. The smaller the particle size is , the faster the particle temperature is , and the final temperature can achieve higher. The appropriate input of water vapor can increase the ratio of H 2 and CO in the product gas and the carbon conversion rate and H2/CO ratio in the steam vaporization process. The carbon conversion rate can reached to 96% and the gasification efficiency is as high as 94 % when the S/B ratio is 1.4. when the input of water vapor is excessive , the furnace temperature will drop down , the evaluation indexes begin to decline and quality of biogas gets poor.