PRESSURE RESISTANT DRAIN PAPER AND DEHYDRATION OF SLUDGE BY PRESSURE RESISTANT DRAIN PAPER

摘要

PURPOSE:To enable to dehydrate sludge under high pressure in a drain paper obtained by adhering a water permeavle film to the surface of a strip like material having continuous grooves, by filling the insides of said grooves with fine particles inert to water to impart water resistance to said drain paper. CONSTITUTION:Water permeable films 2, 2' are adhered to both surfaces of a strip like material 1 having continuous grooves 11, 12 and the insides of said grooves are filled with particulate materials 5, 5' inert to water having a particle size of about 1/2 or less to the short diamether of each goove, mainly 0.08mm. or more such as sand or glass beads. One end 13 of thus constituted drain paper is fused by heating and the resulting drain paper is arranged in the sludge 3 within a pressure container 4 and the opening part 14 of the other end of said driain paper is extended to the outside of the pressure container 4. When water pressure or oil pressure is applied to the rubber bag 6 in the pressure container 4 to pressurize the sludge 3, the moisture in the sludge is filtered out from the water permeable films 2, 2' and discharged from the opening part 14. By this constitution, the water permeable films are prevented from being inserted into grooves in a curued form due to external force by particulate materials.