摘要
为提高污泥资源化,进一步实现污泥热解产物利用的多元化,探究了经机械化学预处理后,CaO、CaO-半焦和半焦3种不同催化体系对污泥快速热解产物特性的影响。结果表明:CaO催化体系下,H_2产率较原污泥提高了80%,通过TG-DTG、FTIR分析发现,添加CaO有助于热解过程中发生固碳反应和CO_2的原位释放,利于CO、H_2生成和半焦产率的降低;采用适量半焦与CaO混合作为催化剂,可以优化热解气品质,显著提高H_2占比,体积分数达到44. 21%,同时促进焦油产生,为后续焦油二次裂解产气提供新思路;完全以半焦为催化剂有利于热解后焦炭孔隙和比表面积的增加,使其具备开发为吸附材料和负载型催化材料的潜力。
In order to improve resource utilization of sludge and further diversification of sludge pyrolysis product utilization,in this study,the effect of sludge pyrolysis characteristics was explored on three different catalytic systems of CaO,CaO-semicoke and semi-coke after mechanical chemical pretreatment. The result showed that H_2 yield of CaO catalyst was 80% higher than that of the original sludge. By TG-DTG and FTIR,we also found that the addition of CaO caused carbon fixation reaction and in-situ release of CO_2 during pyrolysis,which was beneficial to the generating of CO,H_2 and reduced semi-coke yield.Mixing appropriate semi-coke and CaO could optimize the quality of pyrolysis gas,increase the proportion of H_2 significantly even up to 44. 21%. It can also promote the production of tar,which provided ideas for the subsequent secondary cracking of tar. Semi-coke,as the single catalyst,facilitated the increase of pore structure and specific surface area of the semi-coke produced in pyrolysis,gave it the potential to be developed into adsorbent materials and supported catalytic materials.
引文
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