对于低孔、低渗气藏,为了提高单井产能和改善气田开发效益,许多生产井都采用了多层合采方式进行生产. 为了更真实地认识低渗气藏多层合采的渗流特征以及确定最佳合采接替时机,通过设计室内物理模拟实验,模拟气藏多层合采开发过程,研究了地层压力、渗透率及主控因素共同作用下的气藏渗流特征对开发效果的影响以及合采接替生产时机,认为多层合采时,高压、高渗层产量贡献率始终高于低压、低渗层;而对于低压、高渗层,实验初始阶段低压、高渗层的产量贡献率高于高压、低渗层,实验后期从主产气层变为次产气层;在不同的接替时机下,随着接替点压力的降低,采出程度呈现出降低的趋势;低渗层接替生产要比高渗层接替生产效果要好. 采用物理模拟实验研究多层合采产气渗流特征尚属新的尝试,其研究成果对制定类似气藏的合理开发技术策略提供了参考依据.%In order to increase single-well productivity and improve development economics of low porosity and low per-meability gas reservoirs ,many production wells adopt the way of commingled production .By laboratory physical experi-mental analysis ,the development process of commingled production was simulated to study the influences of seepage fea -tures of gas reservoir under the combined action of formation pressure ,permeability and the main controlling factors on the development effect ,and also the timing of production conversion .The results suggest that when commingled production is adopted in gas reservoirs ,the yield contribution rate of high pressure and high permeability layers is always higher than that of low pressure and low permeability layers;As for low pressure and high permeability layers ,their yield contribution rate is higher than that of high pressure and low permeability layers in the initial phase of the experiment ,and they turn from the primary gas pay zones to the secondary gas pay zones in the later phase ;Along with the pressure at the conver-sion points going down , the degree of reserve recovery presents a decreasing trend among different times of production conversion;the effect of production conversion of low permeability layers is better than that of high permeability layers . This is still a new attempt to analyses the seepage features of commingled production through physical simulation experi -ment and the results provide a reference for making a reasonable development technology strategy for similar gas reser -voirs.
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