| 摘要 |
1508079 Rotary filter TEXACO DEVELOPMENT CORP 25 May 1976 [7 July 1975] 21544/76 Heading BID A rotary drum filter (Figs. 1, 2 not shown) is partly immersed in a wax-oil-solvent slurry to be filtered and has circumferentially spaced peripheral chambers connected by respective filtrate pipes to a rotary valve whose lower sector, between fixed blocks 39 and 27 includes an adjustable block 29 whereby the first filtrate fraction, extracted from chambers which have just entered the slurry, is drawn off by suction pipe 26 separately from the second filtrate fraction drawn off by suction pipe 23. The second fraction has been filtered through the filter cake built up on the filtering surface of the drum as it moves through the zone between blocks 39 and 29, and block 29 is adjusted so that the second fraction is clear. The first fraction is monitored by device (36) and directed back to the upstream side of the filter or added to the second fraction by respective valves (38, 37), depending on whether it contains solid wax particles or not. The filter includes a hood enclosing cakewashing spray tubes (31, 32) and a scraper and screw for removing cake from the drum. Pipes 23, 24 and 25 extracting second filtrate and wash liquid from the rotary valve are commoned together. The valve also includes an inlet 33 which delivers flue gas to blow cake from the drum adjacent the scraper. Each peripheral chamber of the drum has leading and trailing filtrate pipes extending to respective apertures 20, 21 in the valve wear plate. |
