Study On System Efficiency Evaluation Method And Improvement Measures Of Dilute Pumping Wells

The system efficiency is an important basis for evaluating the energy consumption and management level of the pumping system.The method of energy consumption test and calculation for oilfield production systems(SY/T5264-2012)is widely used in various oilfields as the standard.However,the method does not consider the specificity of heavy oil mixed wells,which results in the underestimation of pumping effective power and system efficiency.Based on the efficiency data of diluting wells in Tahe Oilfield,the theoretical study is carried out,and the main influencing factors of system efficiency of the diluting wells have been identified.The current standard is further studied to improve the system efficiency calculation for diluting heavy oil wells in Tahe Oilfield.The reason for the inapplicability of current calculation method is analyzed,that is the flow friction resistance from the pomp outlet to the wellhead,which results the lower pumping effective power and system efficiency.On the basis of the existing system efficiency measurement standards,a new method is proposed and applied to calculate the effective power and system efficiency by considering the effects of the annulus-tubing fluid density difference,the tubing friction above the pump outlet and diluting pump.According to the new method,a software for calculating the system efficiency of the diluting wells has been compiled.Some diluting heavy oil wells in Tahe Oilfield are tested and calculated by the new method.The results show this method is available for diluting,common heavy oil and diluting heavy oil wells,which facilitates the comparison of system efficiency.The new method could provide certain significance for the scientific and objective evaluation of the system efficiency in common heavy oil and diluting heavy oil wells.Finally,in accordance with the main influencing factors,the effective technical measures to improve the system efficiency are put forward in a targeted manner.they are applied in the diluting heavy oil wells,and good results have been achieved.