Patent ID: 6615710
Filing Date: 2003-09-09
Classification: B01D,B30B

Abstract:
A screw press apparatus, comprising:a first frame; a second frame opposing the first frame; and a screw press comprising: an outside tube supported on the first and second frames, the outside tube comprising a cylindrical punched plate and a filtering screen fixed to an inner periphery of the cylindrical punched plate; a screw shaft having a spiral screw blade projecting therefrom, the screw shaft being inserted through the outside tube and supported rotatably on the first and second frames; a supply pipe for supplying raw liquid into the screw shaft, the supply pipe being fixed to one end of the screw shaft supported on the first frame; and a cleaning pipe disposed outside the punched plate for ejecting cleaning water to wash the filtering screen, wherein the filtering screen extends between the first and second frames and has a multiplicity of fine filtering holes formed circularly for filtration of raw liquid over a whole circumference of the filtering screen, the screw shaft and the filtering screen are configured to define therebetween a cylindrical space continuously extending from an upstream region at a side of the first frame to a downstream region at a side of the second frame, the spiral screw blade extends in the cylindrical space continuously from the upstream region to the downstream region, the screw shaft has an opening formed in a periphery thereof for supplying raw liquid from the supply pipe to the upstream region of the cylindrical space, the screw shaft and the filtering screen have a radial distance therebetween decreasing from the upstream region towards the downstream region, raw liquid supplied from the opening to the upstream region is pressurized and carried towards the downstream region by the spiral screw blade, while being separated into filtrate outflowing from fine holes of the filtering screen and solids to be discharged as a cake from the downstream region, and the multiplicity of fine holes of the filtering screen have diameters gradually decreasing from the upstream region towards the downstream region.