本文针对多组高灰熔点煤种的高温热天平气化（C-H_2O、C-CO_2反应）实验数据,进行机理性分析,建立了考虑内孔扩散的动力-扩散模型。模型中,使用随机孔模型对低温动力学控制的气化反应速率进行数据拟合,并对孔隙结构参数的合理确定进行了探讨;采用效率因子修正方法,考虑了中温时煤灰孔隙扩散的影响;同时考虑了高温下气膜扩散机理。新模型可以实现三控制区域的统一贯穿,模型预报能够与实验数据有较好符合。高温时,煤焦发生灰熔融现象会降低气化反应速率,模型通过乘积系数的修正,可以较好描述该过程。
The gasification reaction characteristics of several typical Chinese coal chars of high ash fusion temperature were investigated in the TGA with high temperature range for the C-H_2O、C-CO_2 reactions.On the basis of the experimental results,the theoretical analysis is performed,and a new kinetic-diffusion model considering the effect of pore diffusion is proposed in this article.In the new model,the kinetic-control char gasification reaction is described by the popular random pore model for lower temperature cases,with the calculation method of pore structure parameter（Ψ） developing. For relatively high temperature cases,the effectiveness factor method is developed to depict the influence of pore-diffusion.And gas diffusion mechanism in the particle boundary layer is considered as well.Those three control zone can be continuously transited by the new model.And the prediction could be agreed well with the experimental observations.The ash-fusion phenomena could reduce the char gasification reaction rate,which was predicted well taking the correction of the effectiveness factor into account.
参考文献
| [1] | Shiro Kajitani;Nobuyuki Suzuki;Masami Ashizawa .CO_2 gasification rate analysis of coal char in entrained low coal gasifier[J].Fuel,2006(2):163-169. |
| [2] | S. Kajitani;S. Hara;H. Matsuda .Gasification rate analysis of coal char with a pressurized drop tube furnace[J].Fuel,2002(5):539-546. |
| [3] | 乌晓江,张忠孝,朴桂林,小林信介,森滋勝,板谷羲紀.高灰熔点煤高温下煤焦CO2/水蒸气气化反应特性的实验研究[J].中国电机工程学报,2007(32):24-28. |
| [4] | 吴玉新,张建胜,岳光溪,吕俊复.采用简化PDF模型分析分级气流床气化炉的气化特性[J].中国电机工程学报,2008(26):29-34. |
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