Research On Nitrogen-foam Flooding Technology In Min66Block In Jilin Oilifeld

In the process of waterflood recovery, because of the reservoir heterogeneity, theinjection water, edge water and bottom water promote non uniform along the highpermeability zone. Form single dash in vertical, tonguing in horizontal, cause the injectionwater breakthrough in advance, lead to the breakthrough prematurely, even water out. So thatthe low permeability reservoirs don’t work, and reduce the oil recovery. In order to improvethe working degree of the remaining oil, intends to put forward the nitrogen-foam floodingtechnology.The work principle of foam flooding is to use the superposed gas lock effect of thestability foam in water injection layer-JiaMin effect and the expand of the foam bubbles in thepores of the rock, to make the flow resistance of the water in core porous medium redouble,and the surfactant out of could change the surface property of rock in the meantime, and letporous medium surface hydrophobic under certain circumstances, all of these effects couldlimit the water channeling there. Nitrogen-foam flooding technology not only suitable foradjust the interlayer heterogeneities of big reservoirs, but also the flat contradiction andinterlayer conflict.Based on the percolation mechanism of nitrogen-foam, put forward regard foamcomprehensive value that reflect foaming power and stability of the foaming agent as a mainparameter, used to filter foaming agent which used in nitrogen-foam flooding Through theindoor experiments, evaluate the performance of foaming agent frequently-used, and analysisthe influence factors, research the influence for nitrogen-foam flooding effects of gas-liquidratio, permeability and crude oil systematic. Finally analysis the influence for nitrogen-foamflooding effects of reservoir conditions and production factors by numerical simulationmethod, showed the nitrogen foam flooding is more suitable for heterogeneous reservoirs ofpositive rhythm and good connecitivity.The nitrogen-foam flooding technology has been test in Min66Block in Jilin Oilfieldfor8days, inject49770cubic meters in all. The pressure building up during the injection, andget good effect on oil well stimulation.