3 phase decanter centrifuge is the common used equipment for oil sludge separation unit and oily water separation project, based on client’s different requirement for the treatment result, we will select proper equipments, 3 phase decanter centrifuge or 2 phase decanter centrifuge plus 3 phase disc centrifuge. They have their own advantages and disadvantages.
3 phase decanter centrifuge is a solids, liquid, liquid 3 phase separation machine, the 2 phase liquids should have specifically different density, and the solids phase should be specifically heaviest phase, which can be easily separated. The separation principal is sedimentation, when the oil sludge is feed to the centrifuge inlet pipe and enter into high speed bowl, the material rotates synchronously with the bowl. When gravity is different, the generated centrifugal force is also different, the solid phase ( the heaviest phase) with largest gravity, then water phase with 2nd largest gravity , the oil phase with the lightest phase and smallest gravity. The solids phase is in the outtest layer of the screw, the oil inside, the centrifugal force became less from outside to inside. The solids are pushed by the screw conveyor, the water which is heavier is discharged from the nozzle in the upper position of the big end, the oil which is the lightest phase will be discharged from the bottom nozzle of the bid end. The solids, oil, water discharged from 3 phase centrifuge is not with high quality, if your requirement is very concerned about the oil quality for recovery , water quality to be sent to waste water treatment facility, solids quality for disposal, it can not meet your requirement.
Another solution is to use 2 phase decanter centrifuge plus 3 phase disc centrifuge, it separated the working process as solids liquid separation firstly, then liquid liquid separation, with proper chemicals adding and heating, the treatment result can reach expected target.