鼓泡流化床稻草与污泥共气化试验

摘要

对工农业废弃物进行再利用对于保护环境和节约资源具有重要意义.本文在鼓泡流化床上进行了稻草与污泥共气化试验,分别分析了气化当量比、原料含水率和污泥掺混比对气化特性和焦油产量的影响.结果表明:当量比从0.2增加至0.4的过程中,产气中的可燃组分浓度、产气热值和气化效率均呈现先略有增大后逐渐减小的趋势,气化效率在当量比为 0.25 左右最大达到 53.8%;在整个过程中,气化焦油产量随着当量比的增大而逐渐减小.原料含水率的增大对于气化具有削弱作用,随着含水率从5%增大到20%,产气中的可燃组分浓度均逐渐减小,产气热值、气体产率和气化效率在含水率为 20%时均达到最低;焦油产量先增大后有所减小.在污泥掺混比从0增至30%过程中,H2的浓度基本不变,CH4和CO的浓度先增加后减小,产气热值和气化效率在掺混比为20%时均达到最好;焦油产量随污泥掺混比增加先逐渐减小后略微增大.%The recycle of industrial and agricultural wastes is important for protecting the environment and conserving resources. The experiment of co-gasification of rice straw and sludge was performed in a bubbling fluidized-bed. The effects of gasification equivalence ratio(ER),material moisture content and sludge mixing ratio on gasification characteristics and tar yield were analyzed,respectively. The results showed that of the ER increased from 0.2 to 0.4,the content of combustible gas,the low heating values (LHV)of syngas and gasification efficiency increased slightly at first and then decreased gradually. The gasification efficiency reached the maximum of 53.8% when the ER was 0.25;Tar yield decreased as the ER increased. When the material moisture increased from 5% to 20%,all the combustible gas content dropped,so did the LHV of syngas,gas yield and gasification efficiency;Tar yield increased first and then reduced. When the sludge mixing ratio increased from 0 to 30%,the concentration of H2 was essentially unchanged,while the content of CO and CH4 increased at first and then reduced. The LHV, gas yield and gasification efficiency reached the best when the sludge mixing ratio was 20%;Tar yield decreased at first and then increased slightly.