Experimental Study On The Explosion Risk Of Coal Bed Methane Adsorption Tower

Coal bed methane (CBM) resources are super rich in China. But CBM hasn't been utilized effectively. Especially, it mostly uses evacuation to dispose the lower concentration methane, it not only wastes a great deal of green energy, but also aggravates air pollution. At present, using pressure swing adsorption to enhance methane concentration is an effective approach to deal with this problem. The intention of this dissertation is to research safety of methane adsorption tower.This dissertation designed a set of adsorption tower simulated equipment according to the equal ratio principle of some methane tower. On the bases of this, equipped gas distribution system, ignition system, dynamic data acquisition system and PLC control system to compose methane adsorption tower test system. Compare with the traditional criterion which uses pressure only, this dissertation added temperature signal to increase dependability.Firstly, it tested explosion pressure of 0.1MPa,0.2MPa,0.3MPa without adsorption medium. It gained the most dangerous concentration is 9.0%, 9.1%,10.0%, respectively. It was found that the explosion limits of methane-air mixed gas had been extended with the initial pressure increasing. In addition, the explosion upper limit had increased with initial pressure increased obviously but lower limit. The relationship between explosion pressure and initial pressure approached to linearity, however, the increasing trend of explosion has calmed down. Furthermore, inert gases carbon dioxide could reduce the explosion limits and intensity visibly.Then, filled methane adsorption medium in simulate equipment. Altered the height of enter gas layer, the thickness of adsorption layer, and initial pressure. Carried on a great deal of explosion flame propagation experiments, it was found that explosion flame can propagate medium layer on the condition of the higher enter gas layer and initial pressure.By analyzed data, it was found that the penetration capacity of explosion flame positively correlated with methane explosion energy as well as initial pressure, contrarily, negatively correlated with adsorption layer in the simulated methane purified adsorption tower. Comprehensive model has been established by using index model for assessing the feasibility of flame propagating in the simulated methane adsorption tower, as follow, M=pA×vB/hC. This assessment model has been testified that it can use to estimate the fatalness of adsorption tower flame propagation.