Device for preprocessing Zhundong coal before combustion

The invention provides a device for preprocessing Zhundong coal before combustion. The device comprises a conveying device, a coal mill, a coal washing device, a reverse osmosis purifier, a suction filter and a drying device, wherein the conveying device is connected with the coal mill; an outlet of the coal mill is connected with a coal dust inlet of the coal washing device; the outlet of the coal washing device is connected with an inlet of the suction filter; a filtrate outlet of the suction filter is connected with the inlet of the reverse osmosis purifier; an aqueous solution outlet of the reverse osmosis purifier is connected with a water feeding port of the coal washing device; a coal dust outlet of the suction filter is connected with the drying device; a microwave generating device is arranged in the coal washing device; a microwave-assisted extraction agent is contained in the coal washing device; an extraction agent solution is an ammonium acetate solution, an acetate solution or a mixed solution o