In the organic fertilizer machine industry, the applicable raw materials for the production of compound fertilizer by extrusion granulation are more extensive. Roller extrusion granulator has been successfully used for extrusion granulation of more than 20 kinds of materials: urea, ammonium chloride, etc. in nitrogen fertilizers, phosphate fertilizers include ammonium phosphate, ordinary calcium, heavy calcium, phosphate rock, etc. , Potash fertilizer, potassium sulfate, etc., and can add trace elements such as boron, iron, copper, zinc, manganese and so on. In addition, the use of fertilizer extrusion granulation technology can flexibly realize the replacement of product formulas in a very short time, and a set of equipment can produce products with more than 30 formulas.