海上稠油L油田多轮次热化学吞吐复合增效试验与机理OA

Offshore heavy oil cold production wells in the Bohai Oilfield generally suffer from high crude oil viscosity,wellbore blockage,edge and bottom water breakthrough,and rapid production decline.Combined with the existing production string conditions,a combined synergistic technology of thermal-chemical huff-puff is proposed.Relying on the synergistic effect of hot water,gas and chemical agents,this technology can improve well productivity and delay water invasion.The well C3H in L Oilfield has undergone three rounds of combined thermal-chemical huff-puff stimulation,with a cumulative incremental oil production of 0.88×104 t,which further verifies the application feasibility of this technology in heavy oil cold production wells of the Bohai Oilfield.By analyzing the synergistic mechanism of thermal-chemical huff-puff and adopting reservoir numerical simulation to split and calculate the oil increment contribution of each technical measure,the oil contribution ratios of foam,viscosity reducer,hot water and synergistic effect are obtained as 64%,18%,10%and 8%,respectively.The contribution proportion of each synergistic mechanism is quantitatively clarified,which provides a reference for the subsequent optimization of construction parameters and the popularization and application of this technology in similar heavy oil oilfields in the Bohai Sea.