Operation Optimization And Project Setting For Heavy Oil Three Pipe Tracing Gathering And Transferring System

Most of main oilfields in our country have already entered the stage of high recoverypercent of reserves, high water cut and overall decline of production at the present time. Andthe load of oil and gas gathering and transferring system, which has lower operation efficiencyand higher loss, is generally dropped. To reduce energy loss and enhance efficiency, theoperation optimization and project setting of oil gathering and transferring system is necessary.The heavy oil three pipe tracing gathering and transferring flow is studied in this paper, and thefollowing four aspects are mainly involved: (1)The configuration and technologicalcharacteristics of heavy oil three pipe tracing gathering and transferring flow are analyzed, andthe whole system is divided into a set of sub systems which include central oil and gas treatingstation, booster station, gathering network and so on, then energy balance analysis models areestablished, methods of efficiency calculation are also presented respectively. (2)According tothe research on heating mode, network pattern and pipeline number of heavy oil three pipetracing gathering and transferring process, with the adoption of hydromechanics, engineeringthermodynamics and other theories, methods of hydraulic and thermodynamic calculation ofnetwork system are concluded. (3)With the minimization of operation energy as its objectivefunction, and well head back pressure, pump outlet pressure, heavy oil station temperature etcas its constraining conditions, a mathematical model of heavy oil operation parametersoptimization is established. The model is a nonlinear mathematic programming problem that isnot convex or concave. Based on configuration characteristics of the model, it is advised tosolve it by use of sequential quadratic programming algorithm. (4)By using C++ Builderlanguage, a heavy oil three pipe tracing gathering and transferring system efficiency analysisand operation optimization software is programmed. It can realize heavy oil three pipe tracinggathering and transferring system efficiency analysis, operation parameters optimization,project setting simulation and other functions. The software is applied to the optimization ofheavy oil gathering and transferring system of Niu Xintuo, Liao He oil field. Contrasted withdata before optimization, the system efficiency increases by 10.06%, average station efficiency9.35%, average heat energy utilization factor 9.94%, electricity utilization factor 3.78%. Thesystem saves electricity 1.20×106kW·h per year, gas 1.95×106m3, which means it saves energy7.91×107MJ.