Research On Separation Characteristics And Structure Optimization Of Vertical Settling Tank

Water-flooding and terpolymerization flooding has been widely used in oil deposit in China and sedimentation method were adopted in most oil fields.However as a result of constraint of the crafts, settling tanks haves become th e most important device in practice production. By a continuous exploiting, mo st oil fields are going through the stage of high water cut, with a large mount of sewage lifted.A settling tank, whose volume is 10000m3 has been simulated by using th e Ansys software. By way of CFD, physical model of settling tank has been a nalyzed, where non-structural grids were adopted and the impact of the tank’s structure on the internal flow field was also studied. At first a single oil drop was simulated to find its motion law, and then a swarm of oil drops were sim ulated to find their distribution varying with time and motion law. Thus we ca n conclude the mechanism of settling.We have been engaged in the improvement of the structure and crafts in order to shorten the settling time and enhance the separation effect. Furthermor e, we will study the flow field properties to gain a deep insight into the mech anism of settling. Simulation showed that the structure of settling tank has a cl ose relation with the settling efficiency. In the two-stage separation process, the buffer zone and settling zone needed to be improved and optimization of thei r structure will sharply improve the settling efficiency. Consider the above men tions, we changed the structure to make the simulating result to be better with other operation parameters fixed. Besides, a floating device was designed to fi x on the bottom of the settling tank. Evidence shows that tanks equipped with the floating device had a positive effect on settling efficiency comparing with those not equipped.