石莼与褐煤低温共热解热重分析及动力学

将不等量的生物质石莼(SC)加入到褐煤(AL)中进行低温干馏实验,实验表明:随石莼的掺混比增加,热解油产率呈先增加后减少的趋势,在石莼掺混比为30%时热解油产率达到最大值12.50%,热解油中烷烃含量在原有基础上增加了23.54%,在一定程度上提高了热解油品质。利用热重分析仪对石莼、褐煤单独热解及30%最佳掺混比的混合样共热解的热解特性进行了研究,结果表明:石莼的加入使褐煤初始热解温度提前,失重速率变快,在300～700℃之间,实验所得混合样的残重量小于单独热解残重量的理论加权值,表明石莼的添加一定程度上促进了热解反应的进行。混合热解符合一级动力学方程模型,指前因子A和活化能E_a存在补偿效应,共热解时的A和E_a与褐煤单独热解相比均减小。

Thermogravimetric analysis and pyrolytic kinetic study onco-pyrolysis of brown coal and ulva

The low-temperature pyrolysis experiments of brown coal(AL),ulva(SC) and their blends were performed. The results show that pyrolysis oil appears to decrease after the increase trend with SC ratio increasing. When SC ratio is 30%,the yield of pyrolysis oil rises to the highest of 12.50 %. The content of alkanes in pyrolysis oil increased by 23.54% on the basis of original content,improving the quality of pyrolysis oil to a certain degree. The pyrolysis characteristics of SC,AL and the blend was studied by thermogravimetric analyzer. Results show that the presence of SC lowers the initial pyrolysis temperature and fasters the weight loss of AL. The residual weight of blend is less than the calculated value at 300—700℃,indicating the promoting effect of SC on the pyrolysis process. The co-pyrolysis reactions were in accordance with first order kinetic equation model. There exists compensation effect between activation energy(E_a) and pre-exponential factor(A). Both E_a and A of co-pyrolysis decrease compared with those of AL pyrolysis alone.