Continuous separation system

A continuous separation system for separation of solids and liquids contained in a slurry comprising:

• a stationary bottom casing;
• a horizontal screen assembly disposed above said stationary bottom casing and mounted for rotation relative thereto about a vertical axis, said screen assembly having an annular liquid pervious portion coaxial about said vertical axis;
• means for rotating said screen assembly about said vertical axis;
• inlet conduit means disposed above said screen assembly for depositing a continuous slurry layer on top of said screen assembly over substantially the entire radial range of said annular pervious portion such that substantially all of said liquid pervious portion of said screen assembly is covered with said slurry as said screen assembly rotates about said vertical axis;
• vertically adjustable dam means associated with said inlet conduit means for defining a gap above said screen assembly, said gap establishing the thickness of said slurry layer;
• means for creating a vacuum within said bottom casing for drawing liquid from said slurry layer through said liquid pervious portion of said screen assembly into said bottom casing;
• a chamber above said screen assembly;
• a radially extending vertical stationary scraper contacting said screen assembly along a generally radial line wherein material on said screen assembly encountering said scraper is initially deflected upward;
• outlet conduit means proximate said scraper for carrying material out of said chamber, said outlet conduit means having an intake proximate said screen assembly on a side of said scraper remote from said inlet conduit means, said intake being sized to receive material on said screen assembly;
• means for creating a reduction in pressure within said outlet conduit means;
• and
• means for introducing air into said chamber at a pressure above the pressure in said bottom casing and above the pressure in said outlet conduit means so that a first portion of said air passes through said slurry layer to displace liquid into said bottom casing and substantially dry remaining solids;
• said intake of said outlet conduit means being sized relative to the height of material on said screen assembly to permit a second portion of said air to flow into said outlet conduit means and entrain dried solids, carrying them out of said chamber through said outlet conduit means, and substantially complete the drying thereof while avoiding excessive mechanical handling.