The Optimization Design Of Horizontal Steam Injection Well For Heavy Oil Reservoir

With the rapidly growing demand for oil, the exploitation of heavy oil is becoming more important. As to the high viscosity and poor mobility of heavy oil, conventional methods are difficult to exploit cost-effectively. It is necessary to fracture for vertical steam injection well for heavy oil reservoir. The fracture makes the extraction process difficult to predict, so the research of exploitation of heavy oil and optimal design for the heavy oil exploitation is significant.Based on the steam injection heavy oil technology at home and abroad,the general heavy oil extraction mechanism analysis of horizontal steam injection well and the screening criteria are made. Three blocks in Shengli oil field,which suit for steam stimulation, steam flooding and SAGD,are selected according to screening criteria. The three blocks are researched by using CMG's STARS thermal recovery module. First,the influences of well pattern, the distance between wells and horizontal lengths to the exploitation effect are researched and the optimum well pattern, well spacing and length of horizontal well are selected. Then the geological parameters such as reservoir thickness, formation permeability, oil viscosity, oil saturation, edge water and bottom water are researched by using the optimal well pattern. The influence law of steam injection rate, dryness of steam, liquid discharge rate, pressure on the horizontal well cyclic steam stimulation, steam flooding, SAGD are researched. Based on the research,the orthogonal layouts, which are built on the various factors, are numerical simulated according to recovery and with a view of oil production. The factors are sensitively analyzed according to extreme differences. The optimal field development programs are selected according to the best value of the factors. The optimal programs are important guides for the reservoir.