| 摘要 |
<p>797,158. Treating waste effluents; purifying liquids. BAUM, R. A. April 3, 1956, No. 10205/56. Classes 46 and 111. [Also in Group VI] A suspension of material in a liquid, e.g., meat packing plant waste, is withdrawn from a tank 10, Fig. 1, through a mixer fitting 24A (see below) by a pump 11 and passed through a valve 12 to a retention tank 13. The rate of flow is regulated by a float 15 which controls through a unit 16 the compressed air supply 18 to a diaphragm 19 which operates the valve body 21 of the valve 12. Part of the suspension discharged by the pump 11, Fig. 2, is led back along a pipe 61 and through valves 111, 112, Fig. 3, and injectors 113, 114 respectively to the mixer fitting 115 (24A) which is interposed between the pump inlet line 17 and the pump. Air or other gas is drawn in at 24 to the injector 114, and aluminium sulphate solution or other chemical at 25 to the injector 113. The resulting mixtures are passed to a nozzle 119 within the fitting 115, Fig. 3, whence they are directed towards the pump in and with the main suspension stream. In the tank 13, which is maintained under pressure, the treated suspension rises over a baffle 14 and undissolved gas is vented at 27 through a valve 28. The suspension passes from the tank 13 through a pressure release valve 29, controlled by compressed air (32) regulated by a flap-closed Bourdon tube 30 and acting on the valve diaphragm 34, to a distributer tank 36 and over an adjustable weir 40 into a flotation tank 39. The froth of gas and floc rising in the tank 39 is removed to a gutter 43 by a conveyer 44 while the clarified liquid is drawn off through several outlets and passes over an adjustable weir in a chamber 45. Chemical solution is pumped along line 25 from one of two tanks 51, 511, while solution is being prepared in the other tank from concentrate from a tank 54 and liquid from a line 52. The concentration in line 25 is one pound of aluminium sulphate, expressed as Al 2 (SO 4 ) 3 .18H 2 O, per gallon and in the line leading from pump 11 to tank 13 it is 120 p.p.m., this being an optimum value in the range 60 to 180 p.p.m. The peripheral speed of the pump impeller should be between 3500 and 5500 ft. per min.</p> |
