Design And Research Of Integrated Device For Floating Cyclone Of Sewage Produced At Sea

With the continuous development of oilfield development activities around the world,the water content of produced fluids continues to increase.Traditional oily sewage treatment equipment has low processing efficiency,large area,and cannot effectively treat sewage.There is a need to upgrade existing sewage treatment facilities,especially the demand for compact sewage treatment equipment in offshore oil fields.In this paper,the structural model of the air floatation cyclone device is designed based on the inner cylinder and external rotation structure.From the structural design of the device,the effect of the main structural physical parameters of the device on its oil-water separation efficiency,the optimization of the structure of the device,in the specific oil removal efficiency range Starting from several aspects such as the matching degree of the lower oil droplets and the bubble particle size is of positive significance for improving the structure of the existing air flotation cyclone device and promoting its industrial application.The main research contents and conclusions are as follows:Using the computational fluid dynamics numerical simulation software FLUENT to simulate the internal flow field of the floatation cyclone device,the four factors of inlet flow tangential velocity,split ratio,annulus flow channel width,and annulus flow channel height were investigated for oil-water separation The law of efficiency.The results show that when the inlet tangential velocity gradually increases from 1 m / s to 6 m / s,the higher the inlet tangential velocity,it is conducive to increase the velocity difference of the fluid in the flow field and improve the efficiency of oil-water separation.The height of the annulus flow channel has a smaller influence on the oil-water separation efficiency of the cyclone than other factors in a certain range.When the width of the annulus flow channel gradually increases,the separation efficiency of the oil-water two-phase shows a trend of increasing first and then decreasing.The separation efficiency is the highest when the width is 80 mm.As the split ratio gradually increases,the separation efficiency of the cyclone increases first and then decreases.When the split ratio is 18%,the separation efficiency of the cyclone is the highest.Aiming at the optimization design of the main structure of the air floatation cyclone device,a complete design method is formed by using the theory of hydrodynamic computational dynamics and other orthogonal design experiments,and the tangential inlet diameter,the height-to-diameter ratio and the optimization Main parameters such as the inner diameter of the flow stabilizer.The effect of the matching degree of the bubble and the oil droplet size on the efficiency of oil-water separation is analyzed.The results show that within a certain bubble diameter range,as the bubble diameter increases,the flotation performance of the bubble on the oil droplet is decreasing gradually.Under the condition of fixed oil-water separation efficiency,when the oil concentration is low,as the oil concentration increases,the number of oil droplets "catch" upward,the number of bubbles will increase in the radial direction,and then the collision probability of large-size bubbles will increase,And the diameter range of bubbles that can participate in the adhesion of oil droplets will become larger;when the oil concentration is higher,as the oil concentration increases,the collision will change from regular to irregular,and the possibility of collision of largesized bubbles is reduced.The diameter range in which bubbles can be floated by oil droplets shrinks accordingly.