川东北地区河坝异常高压气藏产能评价探讨

Discussion on river dike abnormally high pressure productivity evaluation in north-east of Sichuan area

在气井产能分析中,井底流压是十分重要的参数。川东北地区河坝飞仙关气藏属于异常高压气藏,无法将压力计下到井底,只能根据井口测试压力和产量来计算井底压力。目前计算井底流压的方法较多,但因计算模型及计算参数选择的影响,导致气井产能差异很大,给产能评价及合理产量确定带来极大难度。通过对克拉2异常高压气井井底流压及天然气无阻流量计算方法分析,井筒压力-温度模型法计算井底流压、压力平方法计算气井产能适合河坝异常高压气井。为此,选择井筒压力-温度模型法和压力平方法计算了河坝H井的产能,并与其它方法进行了对比分析,为河坝区块飞仙关异常高压气藏气井产能评价及合理产量确定提供了依据。

In the gas well productivity analysis,bottom-hole flowing pressure is very important parameter.Northeast sichuan river dike Feixianguan is abnormal high pressure gas reservoirs,the pressure meter can't be put in the well bottom,the well bottom pressure can only be calculated through well head pressure and productivity.Currently there are many methods to calculate bottom-hole flowing pres-sure,but under the influence of calculating model and parameter selection,gas well productivity are different,which bring great difficulty to determine productivity evaluation and rational production capacity.The calculation method of Kela 2 abnormal high pressure gas well bottom-hole flow pressure and natural gas open-flow capacity proved that well bore pressure-temperature mode is suitable for river dike abnormal high pressure gas well in the calculation of gas well productivity with the use of bottom-hole flow pressure and pressure-squared approach.Therefore the author se-lected bottom-hole flow pressure and pressure-squared approach to calculated the production capacity of rive dike H well and compared with other methods,the result provided scientific basis for the productivity evaluation and rational capacity of the study area.