Zhao Peiyu, Zhang Guojie, Sun Yinghui, Xu Ying
Key Laboratory of Coal Science and Technology, Ministry of Education and Shanxi Province, Taiyuan University of Technology, Taiyuan, Shanxi, 030024, China.
State Key Laboratory of Coal and Coalbed Methane Co-Extraction, Jincheng, Shanxi, 048012, China.
Environ Sci Pollut Res Int. 2017 Jun;24(18):15240-15253. doi: 10.1007/s11356-017-8916-6. Epub 2017 May 5.
In this article, a comparison will be made concerning the advantages and disadvantages of five kinds of coal mine methane (CMM) deoxygenation method, including pressure swing adsorption, combustion, membrane separation, non-metallic reduction, and cryogenic distillation. Pressure swing adsorption has a wide range of application and strong production capacity. To achieve this goal, adsorbent must have high selectivity, adsorption capacity, and adequate adsorption/desorption kinetics, remain stable after several adsorption/desorption cycles, and possess good thermal and mechanical stabilities. Catalytic combustion deoxygenation is a high-temperature exothermic redox chemical reaction, which releases large amounts of thermal energy. So, the stable and accurate control of the temperature is not easy. Meanwhile partial methane is lost. The key of catalytic combustion deoxygenation lies in the development of high-efficiency catalyst. Membrane separation has advantages of high separation efficiency and low energy consumption. However, there are many obstacles, including higher costs. Membrane materials have the requirements of both high permeability and high selectivity. The development of new membrane materials is a key for membrane separation. Cryogenic distillation has many excellence advantages, such as high purity production and high recovery. However, the energy consumption increases with decreasing CH concentrations in feed gas. Moreover, there are many types of operational security problems. And that several kinds of deoxygenation techniques mentioned above have an economic value just for oxygen-bearing CMM with methane content above 30%. Moreover, all the above methods are not applicable to deoxygenation of low concentration CMM. Non-metallic reduction method cannot only realize cyclic utilization of deoxidizer but also have no impurity gases generation. It also has a relatively low cost and low loss rate of methane, and the oxygen is removed thoroughly. In particular, the non-metallic reduction method has good development prospects for low concentration oxygen-bearing CMM. This article also points out the direction of future development of coal mine methane deoxygenation.
本文将对变压吸附、燃烧、膜分离、非金属还原和低温精馏五种煤矿瓦斯（CMM）脱氧方法的优缺点进行比较。变压吸附应用范围广、生产能力强。要实现这一目标，吸附剂必须具有高选择性、高吸附容量和充足的吸附/解吸动力学，在多次吸附/解吸循环后保持稳定，并具有良好的热稳定性和机械稳定性。催化燃烧脱氧是一种高温放热氧化还原化学反应，会释放大量热能。因此，温度的稳定和精确控制并不容易。同时会损失部分甲烷。催化燃烧脱氧的关键在于高效催化剂的开发。膜分离具有分离效率高、能耗低的优点。然而，也存在许多障碍，包括成本较高。膜材料需要同时具备高渗透性和高选择性。新型膜材料的开发是膜分离的关键。低温精馏有许多突出优点，如产品纯度高、回收率高。然而，随着原料气中CH浓度的降低，能耗会增加。此外，还存在多种操作安全问题。而且上述几种脱氧技术仅对甲烷含量高于30%的含氧CMM具有经济价值。此外，上述所有方法均不适用于低浓度CMM的脱氧。非金属还原法不仅能实现脱氧剂的循环利用，而且不产生杂质气体。它还具有成本相对较低、甲烷损失率低、氧去除彻底的特点。特别是，非金属还原法对低浓度含氧CMM具有良好的发展前景。本文还指出了煤矿瓦斯脱氧未来的发展方向。
