Complete Dry Granulation Process of Double Roller Press Granulator
he entire double roller press granualtor is a dry process, requiring no water, binders, or drying. It consists of six steps: raw material pretreatment → forced feeding → extrusion molding → threshing → screening → finished product. Raw material pretreatment: Organic fertilizer and NPK raw materials are crushed in a half-wet material crusher(compost crusher) , with a fineness controlled below 2mm. The material moisture content is strictly controlled between 6% and 8%. Lumps, stones, and iron filings are screened out. High moisture content easily leads to sticking and roller blockage, while excessive dryness results in poor molding and excessive powder. Multiple raw materials are pre-mixed evenly to avoid component segregation affecting granule quality. Forced feeding process: The mixed material is stored in a buffer hopper, and a variable frequency screw feeder forces the material into the gap between the two rollers. Variable frequency speed control is used to matc...