GB1211950A - Centrifuge - Google Patents

Abstract

1,211,950. Centrifugal separators. ETABS. ROUSSELET (SOC. A. RESPONSABILITE LIMITEE). 27 Nov., 1969 [4 Dec., 1968], No. 57990/69. Heading B2P. In a centrifuge for purifying contaminated liquid a pressure sensitive switch 16, Figs. 1 and 2, is positioned in an outlet pipe 10 connected to an evacuation nozzle 9 and, in use, controls the operation of opening and closing members 17, 18 of the circuit 12, 13, that conducts separated liquid 8 and/or sediment 7 away from the centrifuge, as a function of the pressure existing in the outlet pipe 10. The members 17, 18 may be constituted by electrovalves. In operation, when the nozzle 9 penetrates into the sediment 7, the resulting increase in pressure in the pipe 10 is detected by the pressure sensitive switch 16 which actuates the closing of the electrovalve 17 and the opening of the electrovalve 18. After removal of the components the switch 16 actuates the closing of the valve 18 and the opening of valve 17 for the next removal of liquid. In a modification, the valve 18 is replaced by a bypass valve opening automatically beyond a certain pressure. In Fig. 3, evacuation of stiff, pasty sediment is effected through openings 19 provided in the bottom of the centrifuge bowl 4 by means of a scraper knife 20 which is caused to penetrate the sediment by the pressure sensitive switch 16 as soon as the nozzle 9 comes into contact with the sediment 7. The switch then closes the valve 17, places the scraper knife 20 into motion and causes the nozzle 9 to retract. In a modification, Fig. 5 (not shown) the centrifuge bowl is mounted horizontally and the sediment removed by the scraper knife is evacuated through a pipe extending from one side of the centrifuge bowl.