不同热解方式下长焰煤的热解特性研究比较

Comparative Study on the Pyrolysis Characteristics of Long Flame Coal by Adopting Different Pyrolytic Means

为提高长焰煤热解转化率,研究其热解过程和机理,采用格金干馏设备、固定床和间歇蒸气流化床3种不同热解装置,分别进行长焰煤的低温热解实验。研究结果表明,格金干馏实验中液体产率较高;在固定床低温热解装置中,煤颗粒达到完全热解需要的时间长,热解气体产物中氢气的产率高;在间歇蒸气流化床中,煤颗粒的热解反应速度快,但受热解过程中流化气吹损的影响,半焦产率低;热解气体的组成和分布也随热解气氛而改变,在水蒸气气氛条件下,水蒸气可能参与大分子烃类物质的部分反应,热解气体中CH4和C2以上小分子烃类物质CmHn总含量降低,CO2和CO含量增高。

In order to improve the pyrolytic conversion rate of the long flame coal, its pyrolytic process and mecha- nism were studied. Low temperature pyrolysis experiments were conducted by applying, separately, means of standard py- rolysis apparatus, fixed bed and a batch steam fluidized bed. The experimental results showed that the yield of tar was the highest in the standard pyrolysis apparatus. The long flame coal needed more pyrolysis time in the fixed bed and the yield of hydrogen was also increased. Due to the impact of the fluidized gas, partial semi-coke was lost and its yield was re- duced in the fluidized bed. Moreover, the components and distribution of the pyrolysis product were affected by the py- rolytic atmosphere. There were some significant changes in the composition and the amount of pyrolysis products in the steam atmosphere. The yields of methane and hydrocarbon were reduced, but the amount of carbon monoxide and carbon dioxide were increased.