Numerical Simulation And Experimental Study Of A New Designed Coalescence Plate Coalescer

Up till the present situation,most general oil-gas fields have entered the middle-late stage of oil exploitation in China,and the phenomenon of high water cut in oil fields has greatly increased the load and cost of surface water treatment.How to realize the efficient separation of oily sewage in petroleum and petrochemical industry is an urgent problem to be solved.Among many oil-water separations methods,gravity oil-water separation is widely used because of its stable performance and simple operation.However,the existing gravity settling separation device has some problems,such as long oil-water separation time,huge equipment volume and so on.In order to improve the oil-water separation efficiency of gravity separation,a new coalescence plate coalescer structure is proposed in this thesis,which combines oil droplet coalescence theory,shallow pool theory and oil droplet collision coalescence process.Based on numerical simulation and experimental study,the flow field analysis and performance verification of the designed new coalescence plate coalescer are carried out,which provides the basis for coalescence to enhance the gravity separation process of oil and water,and provides ideas and guidance for coalescence to enhance the gravity settlement process.In this thesis,the Volume of Fluid method is accepted for numerical simulation research on three kinds of coalescence plates,systematically analyze the collision coalescence process of oil droplets in different coalescence plates,and comprehensively analyze the factors such as oil droplet size,collision times,coalesced particle size and oil droplet number,etc.In order to quantitatively evaluate the coalescence performance of oil droplets in different coalescence plates,dimensionless parameter E is introduced to quantitatively evaluate the coalescence efficiency of coalescence plates,and finally the best corrugation suitable for oil droplet coalescence is determined.A three-dimensional model of the new coalescence plate coalescer is constructed,and the internal flow field characteristics and coalescence performance of the designed new coalescence plate coalescer are studied by using Computational Fluid Dynamics and Population Balance Model.By comparing the oil-water separation performance in the sediment device before and after installing the coalescer,and systematically analyzing the influence of the parameters such as the angle of coalescer,the period length,the number of layers and the spacing between layers on the oil-water separation performance,the optimum structural parameters and operating parameters of the new coalescence plate coalescer are determined.in addition,the feasibility and efficiency of the new coalescence plate coalescer designed to enhance the settling separation performance is verified.The laboratory experimental system of coalescence-settlement performance is constructed,and the optimized laboratory prototype of the new coalescence plate coalescer is manufactured to carry out laboratory test research on coalescence-settlement performance.Experiments and simulations show that the oil-water separation efficiency of 1m~3/h is the highest,with the maximum values of 81.3%and 91%.The results show that the oil-water separation efficiency is increased by 50%after adding the new coalescer,and the experiment and simulation has same tend,which verifies the efficiency of the new coalescence plate coalescer designed in this thesis and the accuracy of the numerical simulation method.