高温高压非稳态气水相渗测试装置及方法

目前高温高压气藏气水相渗曲线多采用非稳态测试方法获取,测试装置主要采用回压阀控制流体压力,但高温高压条件下易产生压力波动,气水计量易产生偏差。为此,提出了一种基于电容法的高温高压非稳态气水相渗测试装置及方法,测试装置引入了自主研制的电容式液位计量计,实验温度和压力分别提高到200.0 ℃和80.00 MPa,通过液体体积与电容变化计量产水量,通过电动涡轮计量泵控制流体压力、计量气体体积,根据实验测试数据分析了流体压力和油藏温度对气水相渗曲线的影响。结果表明:相同条件下,实验温度升高,束缚水饱和度变小,气水共渗区域变宽;实验流体压力降低,束缚水饱和度变大,气相相对渗透率变小。研究成果对高温高压气藏开发方案设计、动态分析及气水渗流规律认识具有一定指导意义。

Testing Device and Method for Unsteady Gas-water Relative Permeability under High Temperature and High Pressure

At present, gas-water relative permeability curves of gas reservoirs with high temperature and high pressure are mostly obtained by unsteady testing method. The testing device is mainly equipped with back pressure valve to control fluid pressure. However, the pressure is easy to change under high temperature and high pressure, resulting in deviation in gas-water measurement. For this reason, this paper proposed a testing device and method for unsteady gas-water relative permeability under high temperature and high pressure based on the capacitance method. The testing device was fixed a self-developed capacitance liquid meter. The experimental temperature and pressure were increased to 200.0 ℃ and 80.00 MPa, respectively. The water production rate was measured by the change of liquid volume and capacitance. An electric turbo-metering pump was used to control the fluid control and measure the gas volume. The influence of fluid pressure and oil reservoir temperature on the gas-water relative permeability curve was analyzed on the basis of experimental test data. The results showed that under the same conditions, when the experimental temperature was increased, the irreducible water saturation was lower and the gas-water co-permeation area was wider; when the experimental fluid pressure was decreased, the irreducible water saturation was higher and the relative permeability of the gas phase was lower. The study results are of great significance for guidance in the development scheme design, dynamic analysis and understanding of gas-water seepage rules of gas reservoirs with high temperature and high pressure.