Continuous stirrer tank mixerÁsettlers are still widely used in the treatment of industrial effulents and in the bio-chemical process industry for operations that require high capacity and for stages such as fermentation. The obvious disadvantages of mixing and settling are the capital cost, space requirement and the inventory of material held up in the equipment. An economic design for a contactor would produce the most efficient contact combined with rapid and complete separation of the two phases in the smallest possible volume and time. There are a number of alternatives to the mixerÁsettler, of which the gullwing separator appears particularly promising owing to its simplicity, compact nature and energy efficiency. The gullwing contactor separator is a novel design of equipment that works by turbulent jet contact, combined with instantaneous hydro-cyclone separation for extraction of solute from one solvent to another where the two solvents are immiscible and have a density difference. The fundamental reason why the mass transfer coefficient is increased in the gullwing contactor separator is the high relative velocity between the two phases, which reduces interfacial film resistance. A modified design of a batch as well as a two-stages continuous contactor has been successfully developed and optimized for a test system. To carry out separation in a jet contactor separator, continuous contact of tetrachloroethylene (TCE) '5% Ethyl Acetate (EA) and water is achieved with the help of a recirculation pump. This recirculation pump produces a high velocity of light phase (water), which moves through 20 turbulent jets. When the high velocity streams come into contact with a stagnant pool of droplets forming the dispersed phase (TCE), mass transfer occurs. The heavy phase (TCE ' 5% EA) is broken into discrete droplets and EA is entrained in the light phase (water), resulting in forced diffusion and extraction. Simultaneously, the separation of heavy and light phase takes place as the TCE coalesces under the wings, rotates circumferentially and returns to the bottom of the contactor. The centrifugal force expected to be developed in the gullwing was calculated. It was observed that, using a 65 mm gullwing with 10 mm extra, 20 )4 mm jets per stage, 40 mm heavy phase pool depth and injecting light phase at 2 m/s, a centrifugal force three times greater than gravity was obtained. Total escape axial and radial velocities of the light phase in the gullwing were also evaluated. It was also observed that the total escape, that is, the combination of radial and axial escape, affects the overall separation of two phases in the two-stage countercurrent gullwing contactor separator. The stage arrangement is compact. The design is also potentially capital cost-effective as extraction and separation are carried out in the same vessel. Since any number of stages can be accommodated in the same vessel, the extractor/separator can be tailored to a great variety of extraction processes. (It may be considered to be similar to a horiz...

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