鄂尔多斯盆地大牛地低渗气田产水规律

根据鄂尔多斯盆地大牛地低渗气田的历史生产数据、水样分析资料及天然气饱和含水量计算方法,定性、定量地分析了产水来源。同时,根据平均产气量和累计水、气比对气井进行了分类,分析了气田不同层位与不同井型单井的产水规律。结果表明,鄂尔多斯盆地大牛地低渗气田单井的产水量和产气量均较低;气田产出的水有凝析水、地层水和工作液,以地层水为主。不同层位表现出不同的生产特征。二叠系下石盒子组3层位和山西组1层位为低产水高产气层位,二叠系下石盒子组1层位和二叠系下石盒子组2层位为低产水低产气层位,山西组2层位和太原组2层位为高产水低产气层位。不同井型单井的产气量无明显差别,但水平井的产水量更大,水、气比更高。分析结果对选择排水工艺和分析生产情况具有重要的指导意义。

Water production pattern of Daniudi low-permeability gas field,Ordos Basin

Calculation method of saturated water content of natural gas was adopted to qualitatively and quantitatively analyze produced water sources based on the production data and water sample test results of Daniudi low-permeability gas field in Ordos Basin.Moreover,gas wells were classified according to average gas yield and cumulative water and gas ratio(WGR),and water production patterns of different pay zones and single well of various types were analyzed.It is concluded that both water production and gas yield of single well are low in Daniudi low permeability gasfield in Ordos basin.The produced water consists of condensate water,formation water and operating fluid,of which the formation water is predominant.Different pay zones show different production behaviors.The third pay zone in the Permian Xiashihezi Formation and the first pay zone in the Permian Shanxi Formation feature in low water production but high gas production.The first and second pay zones in the Permian Xiashihezi Formation show both low water production and low gas production.The second pay zone in the Shanxi and Taiyuan formations are characterized by high water but low gas production.The gas production of single wells of different types is almost same,but horizontal wells produce more water with a higher WGR.These results can be used to guide selection of water discharging technologies and analysis of production performance.