| Changchunling and Honggangbei is the new emphasis development block in Jilin oilfield, both the aim layers is Fuyu oil layer. In Honggangbei block, the salinity of formation water is 38597 mg/L, formation temperature is about 98℃, reservoirs average permeability is 0.51×10-3μm2, average porosity is 11.2%, average pore throat radius is 0.414μm, so it is ultra-low permeability reservoir. Now in Hong 75 block the injection water is Taikangzu water, salinity is 1010mg/L, the radius of suspended particulate matter is 6.07μm, the injection temperature on ground is 14-18℃, so compared with formation water, the injection water quality is bad , salinity difference is big , temperature difference is big too. In Hong 75 test block 4 wells were water-flooded rapidly, strong water sensitivity in reservoir restricts injecting water, so the quality of injection water must be improved as quickly as possible. In Changchunling block average porosity is 18.72%, permeability is 213.53×103μm2 ,so it is high porosity and medium permeability reservoir. Reservoir rock clay mineral average content is 15.9%, sensitivity experiment shows medium -high water sensitivity, medium-high alkali sensitivity, high acid sensitivity, no velocity sensitivity. Now the development method is thermal recovery, effect is bad, so the research emphasis of the paper is the two blocks, the research target is high-efficient development method and reasonable injecting water. Through stability experiment, inflation experiment, fluid compatibility experiment, flow experiment, we draw some conclusion. In Honggangbei controlling suspended particle size and concentration, using 40000mg/ L salinity injection water, can improve oil displacement effect. In Changchunling the injection water standard is that the salinity is more than 5500mg/ L, radius of suspended particle is less than 5μm, and less than 2μm if the conditions permit, suspended particle concentration is less than 8mg/l, oil content is less than 20mg/ L, total iron content is less 3mg/ L. Changchunling Fuyu oil layer is unconsolidated sandstone reservoir, the sandstone can be taken out if the injection water flow velocity is big, so the injection velocity must be controlled. |
