Method for producing sodium humate by coal

A method for producing sodium humate by coal comprises the following steps: at first, smashing raw materials, decomposed coal, lignite or peat, then preparing a sodium hydroxide solution through water and sodium hydroxide at the ratio of 22,000:3000, adding the sodium hydroxide solution into a reaction kettle, feeding steam generated in a boiler, heating the sodium hydroxide solution to be 90 DEG C, keeping the temperature, adding pulverized coal to the reaction kettle according to the ratio of the coal to the water to the sodium hydroxide is 1:22,000:3000, and drying after three-stage precipitation to obtain the high-purity sodium humate finished product. The method is simple in process and equipment, can obtain high yield at low cost, and does not pollution the environment.