裂缝-孔洞型碳酸盐岩凝析气井出水特征及预测

随着开采时间的增加，塔中I号坡折带上奥陶统裂缝孔洞型碳酸盐岩凝析气藏产水井数目和产水量都有所增加，从而降低了凝析气井产量，影响凝析气藏开发的整体效果。在总结塔中地区裂缝孔洞型碳酸盐岩凝析气井生产特征的基础上，利用流动物质平衡法对试采井进行能量评价，对有较强地层能量补充的试采井，利用生产气油比和天然气烃类组分的变化规律进行出水预测研究。研究结果表明，碳酸盐岩凝析气井自喷生产期间，随着地层压力下降，气油比缓慢上升，随着地层能量的补充，气油比在一段时间内会相对稳定（约4 000 m³/t），出水前生产气油比缓慢下降至2 000 m³/t，产水后气油比快速上升；同时，在产水前天然气烃类组分发生变化，轻质组分C₁+N₂含量降低约3%~6%，重质组分C₇₊含量较稳定生产时增加19倍以上。

Features and Forecast of Water Output in Fractured Vuggy Carbonate Condensate Reservoir

With increase in production, the number and water production rate of gas wells producing water in the carbonate gascondensate reservoir increases, which reduces the recovery ratio of condensate and natural oils, and impacts the overall effect of condensate gas reservoir development. This article, based on summarizing the features of the carbonate gas-condensate wells in terms of production and water production, makes an energy evaluation of the producing test wells through the flow material balance method, and studies forecast of the water output from producing test wells, with abundant supply of formation energy, according to the changing pattern of production gas-oil ratio and natural gas hydrocarbons. The results of the evaluation prove that the production gas-oil ratio reduces significantly before water output of the carbonatite gas-condensate well; the percentage of light natural gas hydrocarbon components reduces, while that of intermediate and heavy components increases.