PISTON PRESS

PROBLEM TO BE SOLVED: To provide a piston press with excellent maintenability, which can separate a solid component and liquid from a mixture of solid and liquid. SOLUTION: This press comprises: a filtration cylinder 13 wherein at least one part of a side wall is composed of a filtration screen for filtrating the mixture of solid and liquid and discharging the liquid as soon as the mixture of solid and liquid is introduced to the inside; a squeezing piston 14 which is stored above the filtration cylinder 13, and reciprocatably installed in the filtration cylinder 13; a pushing up piston 20 which is reciprocatably installed at the bottom of the filtration cylinder 13; a cleaning means which is installed on an outer periphery of the piston 20 and contacts with an inner face of the cylinder 13 and cleans it when the piston 20 is reciprocated in the cylinder 13; and a solid component removing means for removing the solid component on the piston 20 when the piston 20 is positioned at the upper end of the cylinder 13. Further, a pressing face of the bottom end of the piston 14 may be formed in a manner that a center part is protruded from the peripheral part.