Feasibility study of multiple thermal fluid displacement of conventional heavy oil in Bohai N oilfield

Bohai N oilfield is a typical conventional offshore heavy oil reservoir.Since multiple thermal fluid steam stimulation in 2008,remarkable stimulation effect has been obtained.However,with the process of steam stimulation,problems appeared gradually,such as reduced reservoir pressure,edge water breakthrough and quick cycle production decline.In order to enhance recovery ratio,in view of reservoir characteristics,systematic analysis of the multiple thermal fluid displacement feasibility has been carried out from the aspects of the multiple thermal fluid oil displacement mechanism,adaptability,process parameters,etc.The results indicate based on steam stimulation development the multiple thermal fluid displacement development can improve recovery degree of 14.13%.