Study On Optimization Design Of Crude Oil Stabilization Process In Crude Oil Treatment Station

This project origined from the safety hidden danger management project of the crude oil treatment station in the second Oil Production Plant of Xinjiang Oilfield.Because the crude oil stabilization system of the crude oil treatment station has been suspended due to aging equipment and obsolete facilities and other factors,there was a large amount of evaporation loss,environmental pollution,and safety hazards during crude oil gathering.It is needed to build a new set of crude oil stabilization process.This article mainly aims at designing a crude oil stabilization system with crude oil treatment scale of 200×10~4t/a in the station to ensure that the saturated vapor pressure of the stabilized crude oil at the transmission temperature is not higher than 0.7 times the local standard atmospheric pressure,and the transmission crude oil temperature is 55°C.According to the measured properties of oil and gas,combined with relevant literature and specification requirements,it was determined that two sets of crude oil stabilization processes for negative pressure and micro-positive flash residual heat recovery were separately designed in the station.Through the drawing of the process flow chart and using Hysys software to model the two processes,we simulated the boundary value of two sets of processes which includeded the feed temperature and column operating pressure according to the requirements of the project and the proposed process parameters.The negative pressure temperature was from 56 to 65℃,and pressure was from 0.06 to 0.08 MPa(A),while the micro-positive temperature was from 80 to 90℃,and pressure was from 0.1 to 0.115 MPa(A).Combined with he design scale,the material balance calculations and equipment selections were carried out for two processes.The stable equipment of both processes was a flash tower withΦ3000mm×11500mm;the compression equipment of negative pressure and micro-positive pressure stabilization process were 110kW and 90kW oil-free spray screw compressor respectively;the heating equipment of micro-positive pressure stabilization process was 3000kW phase change heating furnace.In order to increase the economic benefit of oilfield development,two sets of process parameters were optimized respectively,and the technical and economic comparisons between the two sets of processes schemes were performed.The results showed that under the premise of two sets of processe can meet the design requirements,the negative pressure stabilization process has the advantages of simple process,less types and quantities of equipment,and convenient management,the project investment could be reduced by 5.8469 million yuan,the annual operating cost was saved by 0.159million yuan,and the processing energy consumption was reduced by 0.106 kgce/t for negative pressure stabilization process compared with micro-positive pressure stabilization process.Therefore,the residual heat recovery process of negative pressure fiash crude oil stabilization should be used as the crude oil stabilization system process of the crude oil processing station.According to the process flow of design,the energy consumption of the residual heat recovery process of negative pressure flash crude oil stabilization was analyzed,and the measures such as the anticorrosion,heat preservation and environmental protection was carried out.This paper can provide some reference for the design,calculation and selection of equipment of negative pressure and micro-positive pressure flash stabilization process in thin oil stabilization process.