Performance Estimation Of New Technologies Of Improving Reservoir's Exploiting Situation

In this paper, performance estimation and laboratory displacement and stimulation experiments investigations of nanopolysilicon, microbial enhanced oil recovery(MEOR)and biologic enzyme have been done. Three new technologies improve low permeabilities reservoir'exploiting situation.The results show that: Solution of nanopolysilicon makes wettability of cores inverting from slightly water wet to intermediate wettability, from intermediate wettability to slightly oil wet. It can make wettability of cores invert towards slightly oil wet and improve water phase permeability. Thereby injection efficiency is improved and swept volume is extended, which is in favor of enhancing oil recovery. Nanopolysilicon stimulation can enhance oil recovery and optimum injection pore volume is 0.3PV, optimum injection concentration is 0.5%, the value of enhancing oil recovery is 8.8%.The latitude of nanopolysilicon displacement experiments enhancing oil recovery becomes small as permeabilities of cores decline, but falloff rate rises. 0.6PV is chosen as optimum injection pore volume and 0.5% is chosen as optimum injection concentration. The values of enhancing oil recovery of high,medium,low permeabilities are respectively 10.97%, 8.14%, 6.84%; their falloff rates are respectively 39.07%, 44.78%, 52.78%.Microbial solution can decline interfacial tension between oil and water. After oil is affected by microbe, a certain extent, asphalten, paraffin content, gel content, etc. all decline. From various indexs of estimating microbial performances, we can see that overall performance of 1# Microbial solution is better than 2#. The highest temperature in which microbial strains can bear is 90℃, when salinity of water which is used in the experiments is 30000mg/L, the strains 1# and 2# all can grow and reproduce normally, which shows the two strains can be adapt to salinity of formation water in the putaohua reservoir. When permeabilities of cores are high and low, the larger injection rate of microbial solution is, the higher recovery is. The ranges of enhancing oil recovery in the cores of high, low permeabilities are respectively 1.25~3.05%, 1.17~2.86%. In the field tests, mode of high concentration, large slug should be taken as far as possible to proceed with stimulation tests.Biologic enzyme has the ability of flushing, and can make interfacial tension between oil and water reach to quantity degree 10-1. When permeabilities of cores are high and low, the larger injection rate of biologic enzyme is, the higher recovery is. The ranges of enhancing oil recovery in the cores of high, low permeabilities are respectively 1.02~2.59%, 0.98~2.45%. In the field tests, mode of high concentration, large slug should be taken as far as possible to proceed with stimulation tests.