Study On Design Scheme Of Surface Oil Gathering System In Huang 3 Test Area By CO₂ Flooding Technology

CO₂flooding technology can simultaneously improve oil recovery and CO₂geological storage.At the present,this technology has been applied in domestic and foreign oil fields,but the CO₂flooding technology at the most oil fields in China is still in the experimental stage and has not entered the stage of large-scale application.This paper investigated a large number of domestic and foreign literatures,closely combined with the characteristics of surface gathering-transportation technology and development-production status of Chang Qing oilfield to study the oil-gathering system scheme suitable for the Huang 3 test area,laying foundation for the application of CO₂flooding technology in Chang Qing oilfield.Firstly,the pipe network connection path planning of Huang 3 experimental area should be optimized according to its topography and landform characteristics.Based on the preliminary investigation data,a three-dimensional terrain model of huang3experimental area was established.The optimization problem of pipeline network path on three dimensional terrain can be transformed into the shortest distance between two points on the known surface.The pipeline path obtained by ant colony algorithm is5%?30%shorter than manual design result,achieving the expected optimization effect.Oil collecting system adopts the optimized length of pipe,and oil collecting process selects the Serial inbound and direct inbound for the comparative study.The actual pressure drop data were used to select the DE calculation formula as the calculation model suitable for CO₂flooding pressure drop in the Huang3 test area.Through PIPEPHASE simulation,Yuan 29-100 well field position will be added a pressurization point according to the simulation results.According to the analysis,the wellhead without heating single pipe dispersive oil gathering process is adopted.Then,designing the in-station process flow of the well site,the pressurization point and the comprehensive test station is on the basis of the oil collection process plan.Finally,this paper analyze the adaptability of CO₂oil displacement technology to the non-heating gathering-transportation process,and put forward reasonable opinions and suggestions for the frozen blocking problem.