摘要
煤炭地下气化过程中 ,高温的碳与二氧化碳和水蒸气发生的非均相反应决定了出口煤气的组分和热值。鉴于此 ,在煤焦与CO2 和H2 O(g) 反应活性实验的基础上 ,研究了唐山刘庄煤焦与CO2 和H2 O(g) 气化反应的动力学特性 ,确定了其化学反应的速率表达式 ,得出其反应活化能分别为 140 41kJ mol和 171 5 3kJ mol。实验结果表明 ,还原带温度在 10 0 0℃～ 110 0℃时 ,CO2 具有较高的还原率 ;当温度达到 10 0 0℃时 ,H2 O(g) 分解可视为不可逆反应 ,且生成CO的反应速率明显大于生成CO2 的反应速率 ,出口煤气组成中CO的浓度为CO2 的 7倍多。在上述工作的基础上 ,建立了“收缩反应核”模型 。
The kinetic character of CO 2 reduction and H 2O (g) decomposition in Liuzhuang underground coal gasification at Tangshan is studied on the basis of the experiment for reaction activity of coal coke and CO 2 and H 2O (g) The test apparatus, method and test procedure are introduced, and kinetic parameters of the gasification reaction for CO 2 and H 2O (g) have been calculated, the expressions for reaction rate is determined, and the activation energy obtained is 140 41?kJ/mol and 171 53?kJ/mol, respectively Based on the diffusion kinetics theories, “contraction reaction nucleus” model is established, and the relation between polyphase chemical reaction rate and temperature is analysed The results indicate that there is a higher reduction rate for CO 2 when the temperature range of reduction zone is 1?000?℃～1?100?℃ and decomposition reaction of H 2O (g) is regarded as irreversible one when the temperature reaches 1?000?℃ The reaction rate of CO generation is obviously higher than that of CO 2 formation The concentration of CO in gas compositions at vent is more than seven times higher than that of CO 2 The calculation value by the model can be well identical with the experiment result, which proves the correctness and rationality of the “contraction reaction nucleus” model
出处
《燃料化学学报》
EI
CAS
CSCD
北大核心
2001年第3期223-227,共5页
Journal of Fuel Chemistry and Technology
基金
国家自然科学基金 (5 990 60 14 )&&
关键词
煤炭
地下气化
二氧化碳
水蒸气
活化能
收缩反应核
反应动力学
underground coal gasification
carbon dioxide
steam
kinetic character
activation energy
contraction reaction nucleus
