Numerical Simulation Of Flow Characteristics In Wave-plate Coalescence Separator

Corrugated sheet coalescer is the major equipment for removing water from oil. As the tertiary oil recovery technology rapidly developed, the property of produced liquid has changed greatly. Especially the stability of the crude oil emulsified in water has strengthened. The poor efficiency of separator now available could not satisfy the request of industrial application. Separator which is appropriate for tertiary oil recovery technology needs to be developed. The separating performance was studied by researching equipments'flowing properties. The relationship between flow fields distribution and the interior structures was investigated. So the separator's structure was optimized for improving the separating efficiency.In order to optimize water-oil separation equipment, the flow fields with three kinds of inlet components were simulated systematically using CFD software. The computation results were compared and the inlet component which has high performance was selected for the separator. The findings indicated as follows: 1.The entrance component effectively improved the flow field distribution in the separator and slowed down the initial flow field impact. It enable interior flow inside the separator close to plunger flow, suppressing and reducing the eddy current and returns, which was more advantageous to separating process. The centrifugal-type entrance component compares other component performance to be more superior, may choose firstly. 2.When the fluid flow out of perforated plate, the flow field distribution conditions improved obviously. The eddy current and returns is suppressed and reduced.Trajectory of oil droplets were simulated with two-phase langrage model. The relationship between separation efficiency and diameter of the oil droplets as well as resident time was studied. Simulation results of oil droplets dripping process indicated: 1. Efficiency of separation will be improved as the resident time increases. When the oil droplet diameter is smaller than 10μm, it will be very difficultly to remove it from mixture. 2.The corrugated sheet packing needs to be installed to enhance the flowing conditions, so that the oil droplets are more possible to adhere to the packing surface and collide with each other.The simulation results of corrugated sheet coalescer proved as follows:the neighboring fluid channel inside the packing mutually links up allowing fluid to flow crossly which increases agglutination probability and enhances the water-oil separation efficiency. Also more steady space after the coalescer would be helpful for separation.