The invention provides three-stage
extrusion type
coal slime filter pressing equipment and a working method. The filter pressing equipment structurally comprises a thrust plate, a filter plate, filter cloth, a cross beam, a pressing plate, a pressing hydraulic
system, a sealing unit, a feeding unit, a
control unit and the like; columnar protruding structures arranged in an array mode are arranged on the outer surface of the filter plate, and each columnar protruding structure is in the structural form that a cone and a semicircle are combined. According to the requirements of the size and the
dehydration rate of the filter plate, the columnar bulge structures are arranged on the surface of the filter plate by adopting a
topological optimization method, so that the
dehydration rate of the
coal slime is improved, and the separation of a
filter cake is facilitated; the pressing plate is of a sectional structure and is divided into three sections from left to right, and each section is connected with
piston rods of the corresponding three hydraulic cylinders and corresponds to a three-stage
extrusion working mode. And when the previous-stage
extrusion pressure reaches 40% of the threshold pressure, the next-stage extrusion procedure is started. 40% of the extrusion threshold pressure can be set to ensure that the first two-stage extrusion is not finished when the third-stage extrusion process is started, so that the optimal extrusion mode of three-stage simultaneous extrusion is formed, the
coal slime
dehydration rate is increased to the greatest extent, and the filter pressing effect is improved. By adopting the three-stage extrusion mode, the dehydration process of each sub-area can be freely, flexibly and independently controlled, the
toothpaste extrusion type collaborative filter pressing effect is achieved, the coal slime dehydration rate is higher, and the filter pressing effect is better.