氧气对胜利褐煤水蒸气气化半焦结构及反应性的影响

孙加亮; 陈绪军; 王芳; 林雄超; 王永刚

氧气对胜利褐煤水蒸气气化半焦结构及反应性的影响

中国矿业大学(北京)化学与环境工程学院, 北京 100083

基金项目: The 12th Five-Year Plan of National Science and Technology Support (2012BAA04B02).

详细信息

通讯作者:
王永刚

中图分类号: TQ546.2
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出版历程
- 收稿日期: 2015-02-03
- 修回日期: 2015-05-30
- 刊出日期: 2015-07-30

Effects of oxygen on the structure and reactivity of char during steam gasification of Shengli brown coal

School of Chemical and Environmental Engineering, China University of Mining & Technology (Beijing), Beijing 100083, China

Funds: The 12th Five-Year Plan of National Science and Technology Support (2012BAA04B02).

摘要

摘要: 为了研究氧气对半焦的结构变化和反应性的影响,采用不锈钢模拟气流床反应器,在8种不同气氛,800和900 ℃条件下,进行了胜利褐煤水蒸气气化实验。利用拉曼光谱和热重分析仪分别表征了半焦的结构和本征反应性。结果表明,在800和900 ℃条件下,添加的氧气对半焦结构变化的影响方式不同;半焦结构的变化是影响碱金属和碱土金属(AAEM)挥发的主要因素。在不同温度下,添加的氧气对Na挥发的影响和对结构的作用类似,H₂O/O₂混合气氛促使气化所得半焦的反应性进一步降低。半焦的反应活性指数与拉曼光谱谱带比值 I (G_R+V_L+V_R)/I_D具有很好的相关性。
- 褐煤 /
- 气化 /
- 半焦结构 /
- 半焦反应性 /
- 模拟气流床反应器
Abstract: The effects of oxygen on changes in char structure and reactivity during steam gasification of Shengli brown coal were examined. A stainless steel simulated entrained-flow reactor was employed to carry out gasification at 800 and 900 ℃ in 8 atmospheres: pure N₂, 15% H₂O, 25%H₂O and 35%H₂O balanced with N₂; and 1%O₂, 15%H₂O+1%O₂, 25%H₂O+1%O₂ and 35%H₂O+1% O₂ balanced with N₂. The structure of chars was measured by Raman spectrum, and the intrinsic reactivity of chars with air was measured using a thermogravimetric analyzer (TGA) at low temperature (300 ℃). The results show that the effects of oxygen on char structure are different at high temperature (900 ℃) and low temperature (800 ℃) in brown coal steam gasification. The volatilization of alkali and alkaline earth metallic (AAEM) is strongly influenced by char structure. The presence of O₂ during steam gasification has a similar effect on the volatilization of Na to the evolution of structure at different temperatures. Experimental data provided evidence that a mixed H₂O/O₂ atmosphere could promote a decrease in subsequent char reactivity in air at 300 ℃, and that char reactivity could correlate well with the band area ratio, I_{(G_R+V_L+V_R)}/I_D.
- brown coal /
- gasification /
- char structure /
- char reactivity /
- simulated entrained-flow reactor

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