摘要
为了正确评估高含硫气井的储层硫堵伤害,通过收集整理大量酸性气体硫溶解度实验数据,建立了考虑溶质压力特性的典型高含硫气藏条件下元素硫溶解度预测模型。在此基础上,根据气水渗流理论与硫溶解度随压力变化量函数,推导了元素硫沉积量化表征数学模型;采用四川盆地某高含硫边水气藏与典型硫堵气井的基础静态与动态资料等,定量分析了影响气井硫堵状况的因素与储层硫饱和度的变化规律,探讨了缓解储层硫堵状况的技术思路与对策。研究结果表明:(1)通过验证,证明了本文建立的硫溶解度预测模型具有更好的预测性能,预测结果也更可靠;(2)气井硫堵程度受制于多种因素的综合影响,在相同的生产时间下,较大的气井日产气量、储层(初始)含水饱和度、非达西流常数,较小的储层有效厚度、储层(初始)孔隙度与渗透率、井底流压,能够造成更严重的气井硫沉积堵塞状况;(3)随着气井生产时间的增加,气井硫堵区域逐渐向井筒外围地层扩展。在气藏不同开发阶段,应该采取不同的硫沉积治理思路。开发初期,建议采用“控速为先,治理为辅”的治硫思路;开发中期,采取“控治并重”的思路;开发后期,应以经济效益为先,维持气井带液生产是该阶段的重点工作。
To evaluate accurately the extent of sulfur plugging damage in high sulfur gas wells,this paper presents a model for predicting the solubility of elemental sulfur.The model takes into account the solute pressure characteristics under typical high sulfur gas reservoir conditions,and was based on a comprehensive analysis of a significant volume of experimental data on sulfur solubility in acidic gases.Based on the above,a mathematical model for the quantitative characterization of elemental sulfur deposition is theoretically derived according to gas-water percolation theory and the sulfur solubility-pressure function.Finally,we used basic static and dynamic data from a high sulfur edge-water gas reservoir in Sichuan Basin,including a typical sulfur-plugged gas well,to analyze quantitatively the factors affecting the sulfur plugging saturation of the gas countermeasures for alleviating reservoir sulfur plugging.We discussed the variational patterns of reservoir sulfur saturation and strategies for mitigating this issue,and we explored some technical ideas.The results showed that:(1)through validation,it was demonstrated that the sulfur solubility prediction model established in this paper had better predictive performance and the predicted results compared to previous models.(2)The degree of sulfur blockage in gas wellswas influenced by a combination of factors.Under the same production time,a larger daily gas production,initial reservoir water saturation,non-Darcy flow constant,smaller effective reservoir thickness,initial reservoir porosity and permeability,and bottom-hole flowing pressure caused more severe sulfur deposition blockages in gas wells.(3)As the gas well production time increased,the gas well sulfur plugging area gradually expanded into the periphery of the wellbore.Different strategies for sulfur deposition management should be adopted at different stages of gas reservoir development.In the early stage of gas reservoir development,it is recommended to adopt a“rate control first,treatment second”a
作者
王国锋
WANG Guofeng(PetroChina Qinghai Oilfield Company,Dunhuang 736200,China)
出处
《成都理工大学学报（自然科学版）》
CAS
CSCD
北大核心
2024年第1期46-59,共14页
Journal of Chengdu University of Technology: Science & Technology Edition
关键词
高含硫气藏
含硫气井
硫溶解度
硫沉积
预测模型
high sulfur gas reservoirs
high sulfur gas wells
sulfur solubility
sulfur deposition
predictive models
