Laoshan Majiahe Development Zone Water Injection Technology Research And Development

Oilfield developmnent by waterflooding,the geologic characteristics of the Saling Group oil layers are overall understood.Then a great many of studies are performed from several aspects as follows to know the feasibility of waterflooding type at oil layers of Saling Group.Water injection at Low permeability oilfield has become a piece of world-class puzzle.The local potential damage factors at Low permeability reservoir are provoked by foreign fluids to cause multiple formation damage and bring about plugging,which then reduces the percolation of fluids at reservoirs,enhance the injection pressure of injection wells,decrease the injection capacity,and further reduce the oil well productivity,so it is difficult to build a effective driving system between oil and water wells.The Yanchang oil layers belong to a kind of sedimentary exterior sandstone body at delta region.It is a typical low permeability sandstone reservoir,which have definite oil and gas richness and geological reserves.Yet it is difficult to develop this reservoir because of high clay content that causes strong water-sensitivity and velocity sensitivity.On the bases of a lot of data about swelling proof and unplugging for home and abroad low permeabilityThe reservoir properties of Yanchang Group are checked by several instruments as X-ray diffractometer,scanning electron microscope and atomic absorption spectrum,etc..The Yanchang Group is a mediately and low porous,low permeable reservoir with high content of clay minerals include smectite,illite and kaolinite,among which the kaolinite has the most content.The grains at core surface arrange relatively compactly at the reservoir.The porosity develops poorly with bad connectivity.Secondary quartz grows on the particle surface.The feldspar particles can easily be eroded.5 sensitivities of Saling Group cores are evaluated in lab according to the Experimental Sequence Industry Standard of Sandstone Reservoir Sensibility Evaluation.The Saling Group is a kind of strong water-sensitivity,partly strong velocity-sensitivity,strong salt-sensitivity,Moderate apt to strong acid-sensitivity,inferior pressure-sensitivity.In the process of waterflooding,the damage caused by strong water-sensitivity and partly strong velocity-sensitivity should be good dealt with.