Research on the Drilling Technique of Coal Bed Methane

Coal bed Methane(CBM) is commonly known as “gas”，of which the main component is methane. It mainly exists in the coal seam in the adsorption state, not only different from petroleum which is also fluid but in the liquid state, but also different from the conventional natural gas which exists in the formation in the free state. In the present, the drilling technique of coal bed methane is mainly based on the drilling technique of petroleum. But as the coal bed methane is attached to the coal seam and different from the conventional hydrocarbon reservoir in the physical and mechanical properties and in the storage, it determines the particularity of the drilling techniques. This paper mainly discusses the drilling technique of coal-bed methane in order to provide some useful reference. Coal bed methane is an important type of non-conventional natural gas which has great potential for exploration.