太原东山煤地下气化模型试验研究

通过地下气化模型试验，获得了东山煤地下气化过程的一般规律。进行了东山煤空气气化及纯氧-水蒸气气化试验，研究了鼓风量及气氧比对煤气组成的影响、气化过程的稳定性以及试验条件下的煤层气化速率变化，进行了纯氧-水蒸气地下气化的物料衡算。试验结果表明，东山煤空气气化可以生产低热值空气煤气，鼓风量会影响空气煤气的组成；纯氧-水蒸气地下气化可以获得合格的二甲醚合成原料气，但需根据气化工作面的移动及煤气组成变化，采用移动点供风气化维持气化过程连续稳定进行。气化过程的物料衡算可以用来预测气化煤气的基本组成。气氧比影响煤气组成变化，试验条件下适宜的气氧比范围为1.8～2.2。气化工作面扩展速率在供风点附近出现最大值，变化平稳，瘦煤地下气化具有较高的稳定性。

STUDY ON UNDERGROUND GASIFICATION MODEL TEST OF DONGSHAN COAL

Based on the model test, the regularity of Dongshan coal underground gasification was obtained. Air-blown gasification and oxygen-steam-blown gasification were conducted. The studies were focused on the influence of air blast on the gas composition, the influence of steam/oxygen ratio on the gas composition, gasification stability, and gasification rate. In the same time the mass balance of oxygen-steam gasification process was conducted. The results show that the underground gasification of Dongshan coal through blowing air can produce fuel gas with lower heat value, the composition of gas is influenced by the amount of air blast. Underground gasification of Dongshan coal with oxygen-steam as gasifying agent could produce synthetic gas for di-methyl ether synthesis, but moving the agent supply position is needed to keep the process going on according to the movement of fire face and change of gas composition. Mass balance can be used for prediction of gas composition. The ratio of steam to oxygen will affect gas quality and optimum steam/oxygen ratio is 1.8～2.2 for the model test. The gasification face development rate of the test coal changes gently in underground gasification process, which indicates that the underground gasification of lean coal has high stability.