Method for producing coal gas through lump coal gasification

The invention provides a method for producing a coal gas through lump coal gasification. The method comprises the following steps: (1) mixing a first type of lump coal of which the ash fusion point is 1400-1600 DEG C with a second type of lump coal of which the ash fusion point is 800-1300 DEG C at a weight ratio of (0.5-9):(1-9.5) so as to obtain mixed coal; and (2) putting the mixed coal into a fixed bed gasifier for a gasification reaction, thereby obtaining the coal gas, wherein the first type of lump coal and the second type of lump coal are both selected from any one or more of high volatile bituminous coal, low volatile bituminous coal and anthracite. As the two types of lump coal of different ash fusion points are mixed, the problems that the gasification temperature of the gasifier can be limited and furthermore the gasification efficiency of the gasifier can be limited when single lump coal of a low ash fusion point is gasified can be solved, the overall ash fusion point of the lump coal can be incr