注CO2吞吐被认为是解除凝析气井反凝析污染、提高气井产能的较好方法。利用CMG数值模拟软件，以一口实际的含水凝析气井数据为基础，建立了单井径向数值模拟模型。对比研究凝析气井自然衰竭开采和注CO2吞吐不同情况下，反凝析液饱和度和气相相对渗透率的变化规律，并利用陈元千的“动态污染表皮系数”法进行产能提高效果评价。研究表明：反凝析现象在近井带形成了一个10m左右的动态径向污染区，致使气井产能急剧下降。注CO2吞吐可通过CO2与凝析液的反蒸发作用有效地消除近井带的反凝析液污染，从而提高气井产能。CO2注入量越大，吞吐效果越好，但也存在一个最优值（实例为16×104 m3），超过后的产能提高幅度明显减小，而注入速度和焖井时间对产能的提高不敏感。%The CO2 huff-and-puff technology is considered a better technique to remove retrograde condensate pollu-tion and improve productivity of gas-condensate wells.On the basis of actual data of a gas-condensate well containing for-mation water,a single well radial model was established by adopting the numerical simulation software (CMG).It was studied on change laws of retrograde condensate liquid saturation and gas phase relative permeability under the conditions of nature depletion and CO2 huff-and-puff of the gas-condensate well.And then productivity improvement effect was evaluated by using Chen Yuanqian’s method,namely the dynamic pollution skin factor method.Simulation results indicate that because of the retrograde condensation,a dynamic radial pollution area of about 10 meters was formed near wellbore,which leads to a sharpy decrease of gas well production.The formation damage near wellbore can be effectively removed by the reverse evapo-ration of CO2 and condensate liquid.As a result,the gas well production can be increased.The more the injected volume of carbon dioxide is,the better the effect of CO2 huff-and-puff is.There is an optimal value for CO2 injection volume (such as a 160,000 m3 in the example),however,the increase range of the gas well production after the optimal value significantly decreases.In addition,CO2 injection rate and soak time have less impact for the gas well production.
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