Study on the energy maintenance during the development of the complex reservoir.

If the reservoir pressure wasn't properly maintained in the process of oil development,the character of fluid flow through porous medium will be changed,the recovery rate and the benefit of developing would obviously be declined for many types of reservoirs,such as water drive reservoir,high gas/oil ratio reservoir and stress-sensitive reservoir.Based on researching the production characteristic of the complex reservoir,It is elaborated that the energy maintenance has close relation with the formation damage caused by water invasion in water drive reservoirs,degasification in high gas/oil ratio reservoirs,and permeability decline in stress-sensitive reservoirs.Based on the above-mentioned study,corresponding energy maintenance schemes is presented for these complex reservoirs:It will promote the development of high efficiency to the water drive reservoir by proper draw down pressure and compatible well types;It will promote the development of high efficiency to the high gas/oil ratio reservoir and stress-sensitive reservoir by flooding in good time,proper draw down pressure,compatible well type and reasonable oil production rate.