Study On Coalbed Methane Deoxidation Through Means Of The Sodium Sulfite Catalytic Absorption

Coal mine methane (CMM) is released by coal exploitation and the content of methane in CMM is between20%and75%.CMM is abundant in China and it is a kind of CHU-based potentially clean energy. However, it contains10%-15%oxygen, which leads to easily explosion during its utilization. CMM deoxidation can not only mitigate environment pollution, but also provide stable energy supply. The feasibility of chemical absorption method is studied to remove oxygen from CMM in this research.The cheap and easily available sodium sulfite solution was selected as the absorbent. Experiment was carried out in a bubbling reactor to choose cobalt sulfate as catalyst firstly. The process conditions of the absorption were preliminary explored, which confirmed the feasibility in technical of sodium sulfite catalytic absorption method to remove oxygen from CMM. And the absorption process of the CMM contenting15%oxygen was studied in double-stirred reactor with a fixed phase boundary. The effects stirring speed, of concentration of catalyst, temperature, initial concentration of solution and pH were studied respectively. The results showed that the suitable reaction conditions were temperature of60℃, solution concentration of0.4mol/L, catalyst mass concentration of0.9g/L and pHlO. Finally, the kinetics of sodium sulfite oxidation was studied, which turned that the macroscopic reaction was divided into two parts:reaction control and oxygen diffusion control. The characteristic concentration was related to oxygen partial pressure. The reaction rate equation was in oxygen diffusion control area and in reaction control area.