Research On Reasonable Matching Between Supply And Demand In Crude Oil Gathering And Transportation System Based On Energy Level Analysis

Energy shortage and environmental pollution have always been the topic of concern.With the continuous exploitation of oil,the crude oil production of some oil fields decreases,and the water content of produced liquid increases,leading to the problems of high energy consumption and low efficiency in the process of gathering and transportation,and serious energy waste.As a result,energy level analysis theory based on energy analysis and exergy analysis should be applied to the crude oil gathering and transportation system to find out the rationality of matching between supply and demand,so as to reduce energy waste and improve energy use.Combine with the heating technology of oil field crude oil,based on the new energy technology can realize the characteristics of doubling the original heating energy consumption,this paper puts forward three heating modes of crude oil gathering and transportation system and carries on the process design,equipment selection and simulation.After comparative analysis,it is of great reference significance to choose a more reasonable heating system for energy saving and consumption reduction in oil gathering and transportation system.In this paper,the crude oil gathering and transportation system of an oilfield block in northwest China is taken as the research object to evaluate the energy use,and the crude oil gathering and transportation system is divided into oil gathering wellhead subsystem,transfer station subsystem and joint station subsystem,and the energy flow diagram of each subsystem is drawn.Firstly,the energy analysis of the main equipment in the subsystem shows that the utilization of electric energy of each subsystem in the gathering and transportation system is better than heat energy.Among them,T1 and T6 transfer stations in the subsystem of the transfer station have the lowest thermal energy utilization rate,which has the largest gap with the benchmark value of energy saving of oil field enterprises,and serious energy quality loss.Exergy damage coefficient in the heating furnace is much higher than that of the pump,and the exergy flow entering each subsystem is mainly dissipated by the heating furnace.Exergy loss coefficient of heating furnace in T1 and T6 transfer stations are generally over 70%,causing serious waste of energy quality.The energy level balance coefficient of the gathering and transportation system is 0.536,indicating that the energy level of the input and output of the gathering and transportation system change greatly.In the process of energy conversion and transfer,a lot of exergy degrad into anergie.The highest energy level balance coefficient of the subsystem of the transfer station is 0.511.Energy and exergy loss further determined that the unreasonable energy use links of the gathering and transportation system are the heating furnaces of the transfer stations T1 and T6.In order to improve the energy consumption of gathering and transportation system and reduce the waste of energy and mass,the heating mode of crude oil in the transfer station is changed.Solar energy and oilfield sewage source heat energy are used to heat the crude oil exported from the transfer stations T1 and T6,and the simulation platforms of solar crude oil heating system,sewage source heat pump crude oil heating system and solar composite sewage source heat pump crude oil heating system are designed and built.Energy level equilibrium coefficient,exergy damage coefficient,system operation characteristics of different crude oil heating processes are compared and analyzed.The results show that the three heating systems could meet the heating demand of crude oil.After the heating mode is changed,energy level equilibrium coefficient and exergy loss coefficient of crude oil heating processes decreased greatly,in order of magnitude: solar composite sewage source heat pump crude oil heating process < sewage source heat pump crude oil heating process < solar oil heating process.The COP value of the systems are successively: solar composite sewage source heat pump crude oil heating system > sewage source heat pump crude oil heating system.In conclusion,the solar energy composite sewage source heat pump crude oil heating system has the highest matching degree of supply and demand,and the best energy-saving effect.Taking the annual cost value of the solar energy composite sewage source heat pump crude oil heating system as the evaluation index,orthogonal test is used to optimize the combination of equipment in the system.After optimization,the present value of the total cost is reduced by 1,230,700 yuan,which is converted into an annual cost reduction of 143,700 yuan,improving the economy of the system.The above research provides reference for the multi-energy complementary green development of the oilfield gathering and transportation system.