The screw extrusion solid-liquid separator has the characteristics of small size, low speed, simple operation, convenient installation and maintenance, low cost, high efficiency, fast investment recovery, and no need to add any coagulant. It can remove raw livestock manure Separated into liquid organic fertilizer and solid organic fertilizer. Liquid organic fertilizer can be directly used in crops. By absorption, solid organic fertilizer can be transported to areas lacking fertilizer for use. It can also improve soil structure and can be made into organic fertilizer through fermentation. Compound fertilizer.