The Research To The Key Technology Of Closed Desanding Based On Crude Oil

As the Crude oil resources are widely distributed and abundant, at the same time, the demand for oil and gas increasing and the future will face a variety of practical issues such as energy shortages, heavy oil resources in the development and use are becoming increasingly important. In order to reducing heavy oil development costs, while improving economic efficiency, cold production and reasonable sanding technology have been proposed. The sand production from oil well increase production capacity and yield-increasing effect of sand in heavy oil reservoirs very significant, domestic and foreign there are many successful examples. When sanding reservoir will take place a certain degree of compaction, so that pore pressure increases, driving energy increases, the release of the reservoir capacity; the same time, creates wormholes and foam stability of the oil flow with sanding, enhanced the harvesting reservoir rate.With the application of Cold Production with Sand and reasonable sanding, the problem of sand in the heavy oil recovery is inevitable. Sand contained in crude oil cause damage to the ground gathering equipment, including plug and corrosive wear of equipment and piping, the volume of corresponding accumulator is decreasing; Sand into the ground equipment, which bring all kinds of damage and impact to ground equipment; at the same time Oil-bearing sand if not handled properly causes pollution to environment. Therefore, configure of the appropriate surface treatment process of oil and sand is essential. Conventional desanding techniques does not combined with the viscosity reduction techniques, So that the desanding inefficient; process complex, covers an area of great and increase in processing costs and reduced efficiency.The larger size of sand can be removed by the sedimentation and the smaller sand can be removed by hydrocyclone devices. Hydrocyclone is a separation plant used to separate non-uniform phase mixtures. It can be used to complete the liquid clarification and to wash particles, liquid degassing and grit removal, grading and classification of solid particles and the separation of two non-miscible liquids and others. Hydrocyclone separation technique is simple and convenient operation, high separation efficiency, no rotating units, small size and easy to realize automatic control. On the offshore platform, if the sand mixed with oil is discharged into sea unsatisfactory the standard, it will pollute the sea. It will cause a serious of marine pollution; this is a problem that should be solved quickly.Then rotating liquid desander’ process on the basis of its working principle is written in this paper, FLUENT-a influential computational fluid dynamics(CFD) software is used to Simulate the flow field of the hydrcyclone in this thesis. After selecting the mathematical modal exactly and defining the boundary condition accurately, this thesis simulates the flow field of the normal hydrocyclone, with crude oil as medium. The Correctness of the simulation result is checked up in according to the vortex and rotation flow theories and some testing result.On the basic of the simulation, the major parameters and the relationship of them in the whole flow field are exhibited and analyzed wholly. According to the simulation results and correlative theories a viewpoint about the radial velocity of the hydrocyclone is presented and relative theoretic prove is presented.The requirements for the design of the hydrocyclone desander equipment with compact structure, applicable to offshore drilling platforms, and carrying out CFD simulation are discussed in this paper, the results showing that the particle size of75of sand, grit removal efficiency above90%.