Coal water slurry additive as well as preparation method and application thereof

The invention relates to the field of coal chemical industry, and discloses a coal water slurry additive and a preparation method and application thereof. The method comprises the steps that sodium lignin sulfonate, sodium methylene dinaphthalene sulfonate, soluble chitosan and sodium persulfate are evenly mixed with water, then heating is conducted, sodium tripolyphosphate and sodium acetate are added, stirring is conducted, and the coal water slurry additive is obtained, wherein on the basis that the total weight of the sodium lignin sulfonate, the sodium methylene dinaphthalene sulfonate, the soluble chitosan, the sodium persulfate, the sodium tripolyphosphate, the sodium acetate and the water is 100 parts by weight, the weight of the sodium lignin sulfonate is 22-29 parts by weight, the weight of the sodium methylene dinaphthalene sulfonate is 25-32 parts by weight, the weight of the soluble chitosan is 2-4 parts by weight, the weight of the sodium persulfate is 4-7 parts by weight, the weight of the sodi