棉浆粕黑液固形物与苇浆黑液固形物混合燃烧性能的研究

Combustion Properties of Mixed Solids of Linters Pulping Black Liquor and Reed Pulping Black Liquor

关键词:  黑液  燃烧  碱回收

Key Words:blank liquor  combustion  alkali recovery

摘要:本研究以棉浆粕黑液固形物和苇浆黑液固形物为研究对象,分析了其物化性能,测定了两种固形物以不同比例混合样品的膨胀体积及发热量,采用热重分析仪对混合固形物样品进行了热解特性研究,并进一步采用Coats-Redfern法对混合固形物样品燃烧过程的活化能和频率因子进行了求解。结果表明，棉浆粕黑液和苇浆黑液元素含量相差不是太大,二者混合固形物的燃烧是一个比较复杂的过程,大体可以分为4个阶段：①样品水分蒸发阶段；②有机物发生裂解产生大量挥发性物质；③高分子化合物进一步分解和发生炭化反应；④碱金属盐发生熔融、挥发、分解及剩余固定碳的燃烧。随着苇浆黑液固形物在混合固形物中比例的增加,固形物的活化能会降低、频率因子和膨胀体积会增加,固形物燃烧性能显著改善。

Abstract:The physicochemical properties of the linters pulping black liquor solid and reed pulping black liquor solid were analyzed. Volume expansion, calorific values and pyrolysis characteristics of the solid samples containing different ratios of the two solids were studied, and activation energy and frequency factor of the samples in combustion process were further calculated using coats-Redfern method. The results showed that: there were some difference between the components of the two solids. The combustion of the mixed solid was a complex process, and it could be divided into four stages: ① drying, ② devolatilization or pyrolysis, ③ char burning, and ④ smelt coalescence. With the increase of reed pulping black liquor ratio in the mixed solid, solids activation energies would decrease, frequency factor and volume expansion would increase, solid combustion performance was significantly improved.