异常高压特低渗透油藏的开发方案

Development program of abnormal high pressure and low permeability reservoirs

针对异常高压特低渗透油藏开发过程中压敏现象严重,初期注水、注气补充能量难以实现的特点,研究了该类储层及流体性质,建立了油藏地质模型和数值模拟模型。通过数值模拟和经济评价,确定了该类油藏的合理开发方式和最优开发方案。结果表明:异常高压特低渗透油藏开发初期应依靠天然能量进行衰竭式开发;依靠天然能量进行衰竭式开发采出程度达17％,但没有稳产期,产量递减较快,而且开发初期油井的产量递减速度大于后期;井距越小,井间干扰越大,年产油量递减越快,导致平均单井累计产油量减小;大斜度井具有较大的开发优势。

In view of the serious pressure-sensitivity and the difficulties in energy supply in flooding and gas injection in the early days during the development of abnormal high pressure and low permeability reservoirs, the behavior of reservoir bed and fluid are studied and the geologic model of reservoirs and numerical simulation model are established. By numerical simulation and economic evaluation, an optimization of reservoir development program is decided. As a result, natural energy is used in abnormal high pressure and low permeability reservoirs during early time of oilfield development, which results in an increased recovery ratio of about 17%. But at this stage stable production cannot be maintained and the output is decreased quickly and the output decrease at the beginning is more rapidly than later on. The smaller on the intervals between the wells, the greater the interference between the wells, and the larger the decrease of the annual oil production.