The Study On The Coalescence Seperation Of Refinery Oil-Cominated Sewage

Coalescence separator is an important equipment to perform oil-water separation using physical methods. Regarding flow characteristics and separation characteristics, further study was made on buoyant discipline before and after each separator structure. It was based on overall measurement of the relative concentration distribution, separation efficiency and grade efficiency of droplets in coalescence separator that internal components are optimized to improve the separation efficiency.Experimental study on portal components, separation components, coalescent components and flow-stabilizing components demonstrates that oil-water mixture enters the coalescence separator in a relatively high turbulent type. Portal components can decrease the turbulent energy and pre-separate the mixture. Orifice plate can furthermore stabilize the fluid, ensuring that the fluid enters the main separation zone as laminar flow. Coalescing plate group can help the oil droplet float up to enhance the separation efficiency. Oil scratch plate can cause vortex in fluid, resulting in back mixing.Meanwhile, the inclined plate and corrugated sheet coalescence materials were optimized. Study has shown that plate length, plate spacing and plate obliquity can only be adjusted in a limited range to achieve relatively better separation efficiency. Corrugated sheet packings provides interlaced channels for fluid, which increases the coalescence area. These channels have facilitated the collision and coalescence of oil droplets, which enhanced the separation efficiency remarkably. It is also found that efficient separation can't be achieved solely by gravity when the oil droplets size is less than 15μm.In addition, the critical floating rate of oil droplets in plug flow model is deduced under postulated condition so that a grade efficiency model is established. Separating temperature, flowability of equipment and demulsifiers can be improved to boost the separation efficiency. This model can aid the development of highly-efficient coalescence separator.