Method for obtaining clean gas via destructive distillation of coal

The invention discloses a method for obtaining clean gas via the destructive distillation of coal, comprising the steps of: (1) carrying out destructive distillation on the coal in destructive distillation condition to obtain crude gas, wherein the crude gas contains carbon monoxide, hydrogen, methane, carbon dioxide, tar and water, and the boiling point of the tar is higher than that of the water; (2) contacting the crude gas with an organic solvent to obtain a first gas product and a first liquid product, wherein the contact condition of the crude gas and the organic solvent is that the temperature of the organic solvent is 70-150DEG C and the time is 10-120sec; and (3) cooling the first gas product to obtain the clean gas and a second liquid product, and separating out the second liquid product. By adopting the method in the invention, the coal tar with water content less than 1% by weight can be directly obtained, and the oil content in the separated water is less than 200mg/L.