大庆徐深气田气藏相态与渗流机理研究

Phase State and Percolation Mechanism of Gas Reservoirs of Xushen Gas Field in Daqing

大庆徐深气田属于低渗透砾岩、火成岩气田,气体中CO2含量不同,气田发现以来,未对不同含量的CO2相态进行过系统测试,因此无法确定在计算储量时偏差系数的取值是否合适,以及气藏中含水量与水中溶解天然气含量是多少。在岩心渗流过程中,由于砾岩颗粒大,火山岩储层非均质强,小岩心测试渗流机理无代表性。采用不同含量的天然气进行了PVT测试、气中水含量和水中气含量测试;采用全直径岩心研究了储层水气相渗、流速敏感性、启动压力、应力敏感性,并对测试结果进行分析和总结,对大庆徐深气田及相同类型气田开发均有较好的指导意义和应用前景。

Xushen Gas Field in Daqing was a conglomerate and volcanic reservoir with low permeability.Different contents of carbon dioxide existed in gas.it was not systematically tested since the gas field was discovered,so the gas coefficient of variation could not be determined during the calculation of reserves and water content in gas and gas content dissolved in water could not be obtained.Result of small size core test was no representative for big size conglomerate grain and strong heterogeneous volcanic reservoir.Different contents of gas was used for testing water content in gas and gas content in water.The water-gas permeability and flow velocity sensitivity,starting pressure and stress sensitivity are studied through full diameter core analysis and the results are summarized and analyzed,it provides guidance for the development of Xushen Gas Filed and similar gas fields,it has good application prospects.