GB963974A - Method and apparatus for contacting phases of different densities - Google Patents

Abstract

<PICT:0963974/C1/1> <PICT:0963974/C1/2> An apparatus for mixing two liquid faces of different density and subsequently separating them comprises a container in which the flow from the rotor is arranged to change from a tangential to a radial flow. The rotor 1 is constituted by a flat circular plate 2 having eight depending vanes 3 and the diffuser 5 is constituted by an annular plate 6 having eight depending vanes 7 disposed regularly and radially of the rotor axis. The two phases flow to the centre of the rotor through an inlet pipe 8 in the direction shown by the one of the lower arrows and the outlet flow is shown by the upper arrows. Each arrangement of the rotor can constitute a stage in a multistage stage can be generally used with 10 to 16 stages.ALSO:<PICT:0963974/C4-C5/1> Crude soap is heated to 80-90 DEG C. and pumped by means of pump 40 to the washing unit at a predetermined rate in an even flow. The anhydrous soap content of the crude soap should not exceed 57%; it may be adjusted by mixing in a small amount of spent lye from pipe 41. The brine, of a constant predetermined composition, after heating to about 90 DEG C. is fed through inlet pipe 42. The flow of the brine is controlled by a valve 43 responsive to the interfacial float 44. The mixture of crude soap and lye enters the unit through the inlet distributer 45. The soap separates from the lye and floats upwards under the conical baffles 28, 29, until it reaches the rotor 1. The lye settles to the bottom and is partly pumped round the circulation system again, partly taken out of the system as spent lye through pipe 41. The rotor 1, being a pump wheel, circulates the lye in the lowest section continuously, the lye flowing to it through the narrow space between the conical baffles. The soap from the bottom of the tank and the lye in the bottom section mix in the rotor of that section and the resulting intimate mixture of lye and soap is thrown out of the rotor against the diffuser and flows then radially in a quiet fashion, into the settling space of the bottom section. The soap floats upwards and passes into the rotor of the next upper section. The lye flows downwards and then upwards between the conical baffles, partly into the rotor of the bottom section again, where it is mixed with fresh soap, and partly into the bottom of the tank, to replace the outgoing glycerine lye, which is withdrawn from the lye circulation system. All the intermediate sections of the washing unit are alike. The soap is settled in the top section. The settled soap 48 runs off over a weir 46 and pipe 47. The sodium chloride may be wholly or partially replaced by other salting out electrolytes such as sodium hydroxide and the temperature should not be allowed to drop below 85 DEG C. A modified arrangement for the neutralizing of a glycerine lye containing up to 2% of a free alkali with fat containing up to 20% of free acids is described in Fig. 13 (not shown).