GB1309344A - Device for evaluating the quality of cake in intermittent filters - Google Patents

Abstract

1309344 Measuring parameters of cake V P BONDAREV G V TUSUNIAN G G BUDENNY N V MGELADZE A V ANISIMOV G M SARADZHEV S E SHAKHBUDAGIAN-SHOU and L V GRINGOLTS 10 March 1971 6497/71 Heading G1N In an arrangement wherein a slurry is filtered to form a cake which is subsequently washed and dried, sensors are provided to detect cake thickness, the degree of washing and the degree of drying, and a single electrical circuit is common to the measurement of all three perameters. As shown a slurry flows from an inlet 5 through a manifold 5 and a filter chamber 4 to an outlet pipe 11 and forms a cake 4. Cake thickness sensors 1, 2 detect the conductivities of the materials in the chambers 5 and 4 respectively and with the ganged switches 15, 16, 22, 23 in the position a shown their signals are fed to a differential amplifier 20 whose output is indicated on a meter 21. This output which increases as the signal from sensor 2 decreases due to increasing cake thickness is fed through a cali- bration resistor 23 to an amplifier 27, and, on the attainment of a given thickness, an alarm 28, actuating mechanism 29 and fitter sequence switching unit 17 are actuated consecutively. The washing step is then initiated when the switches are set to position b and washing liquid flows through the filter, the conductivity of the inlet and outlet liquids being detected by sensors 9, 10. The difference, initially high, is detected by the amplifier 20 and decreases to a level set by resistor 24 when alarm 28 and unit 17 are again operated. Air is next fed through the filters and sensors 12, 13 detect the conductivities in the chambers 5 and 4 respectively, the latter being dependent on the degree of dryness of the cake. Again at a given value; set by resistor 25, switch 17 is operated to effect discharge of the cake and recommencement of the cycle.