论文部分内容阅读
对苏里格气田40块基质岩心(覆压渗透率为0.002×10 3~100×10 3μm2)进行毛管压力测试,精细刻画不同类型砂岩孔喉结构特征,在此基础上,设计气体在不同渗透率均质砂岩、非均质砂岩以及不同含水条件下的渗流实验,研究气体在致密砂岩中的渗流特征。研究表明,纳米孔喉、微毛细管孔喉是致密砂岩流体渗流的主要通道,天然气或气-水在其中流动时受到的阻力远大于在常规或中高渗砂岩中的流动阻力。衰竭开采模拟实验表明,天然气在渗透率小于0.1×10 3μm2的不含水砂岩或渗透率小于1.0×10 3μm2的含水砂岩中渗流时,气体渗流阻力较大,存在启动压力,含水对岩心气体渗流影响较大,含水饱和度较高时,储量动用程度低。采用长岩心衰竭开采实验检测各测点压力拟合计算的压力梯度对于井控半径预测和储量动用评价更具科学性和实用性。
Capillary pressure measurements were performed on 40 matrix cores (pressure-bearing permeability of 0.002 × 10 3 to 100 × 10 3 μm 2) in the Sulige gas field to characterize pore-throat structures of different types of sandstone. On this basis, Rate homogeneous sandstone, heterogeneous sandstone and seepage experiment under different water conditions to study gas seepage characteristics in tight sandstone. The results show that the nano-pore throats and micro-capillary throats are the main channels for tight sandstone fluid seepage. The resistance of natural gas or gas-water flowing in it is far greater than the flow resistance in conventional or medium-high-permeability sandstone. The depletion mining simulation results show that when the seepage flow of natural gas in the water-free sandstone with permeability less than 0.1 × 10 3 μm 2 or water-containing sandstone with permeability less than 1.0 × 10 3 μm 2, gas seepage resistance is large, and there is the influence of starting pressure and water content on core gas seepage Large, high water saturation, the low level of utilization of reserves. It is more scientific and practicable to predict the well control radius and evaluate the reserves by using the test of long-core failure exploitation to measure the pressure gradient of each measured point fitting.