The plugging effect of micro crosslinked polymer microspheres was studied by using nucleopore membrane filtration experiment. The experimental results show that the salinity has a great effect on the plugging effect of SMGm microspheres. With the increasing of NaCl concentration, the plugging effect becomes better. Under the conditions of same pressure and microsphere concentration, the filtration time of SMGm microspheres is better than that of high pressure. The results show that the effect of concentration on the filtration time is complicated and there is no obvious regularity.

In the process of bottom water reservoir development, bottom water coning leads to the problem of increasing water content in production wells. A three-dimensional vertical-well reservoir physical simulation device was established, and was used to study the nitrogen injection for controlling bottom water coning. The influencing rules of nitrogen injection timing, injection rate, injection volume and shut-off time were studied. The research shows that the production wells to injection of nitrogen in bottom water reservoir can effectively reduce the produced liquid water content, prolong production time, so as to achieve the effect of stabilizing oil production by control of the bottom water coning. When the nitrogen injection was carried out, the injection rate of nitrogen had little effect on the water control effect, and the injection rate of nitrogen and the time after the injection of gas had a great influence on the effect of water control.

       The matching relationship between the size of SMG-mm crosslinked polymer microspheres and the pore size of the nuclear membrane was studied by filtration experiments. The results show that the plugging effect of the microspheres with different pore sizes is very different, and there is a membrane pore size matched with the size of the microspheres. When the concentration and membrane pore size are the same, the pressure has a significant effect on the filtration results. In a certain concentration range, with the increase of concentration of microspheres dispersed system and filtration pressure, plugging effect is better. While when the concentration exceeds the optimum value, the performance of the plugging effect is more terrible; SEM observation results show that the effective plugging can be formed when the diameter of the microspheres and the pore size of the membrane are the best match.