疏松砂岩稠油油藏油井产能下降潜在因素分析  

Potential factors analysis of well productivity reduction in loose sandstone heavy oil reservoir

作　　者：唐洪明[1,2] 朱柏宇 龚小平[3] 陈华兴 熊浩[1,2] 张轶 

机构地区：[1]西南石油大学油气藏地质及开发工程国家重点实验室,四川成都610500 [2]西南石油大学地球科学与技术学院,四川成都610500 [3]中国石化西南油气分公司川东北采气厂,四川阆中637402 [4]中海石油(中国)有限公司天津分公司,天津300452

出　　处：《油气藏评价与开发》2017年第6期39-45,共7页Petroleum Reservoir Evaluation and Development

基　　金：国家科技重大专项"渤海油田高效开发示范工程"(2016ZX05058)

摘　　要：渤海湾盆地金县1-1油田东营组油藏属于疏松砂岩常规稠油油藏,该油藏处于开发早期,许多井产能却发生快速下降。针对该问题,以储层地质研究为基础,利用敏感性实验、乳状液黏度变化实验、注入水与地层水结垢实验、扫描电镜分析、X-射线衍射等方法综合分析了产能下降因素及机理,并分析统计了所有生产动态资料,动静结合,总结出不同因素在生产动态曲线上的识别标志,提出了相应的措施建议。实验及动静态结合研究发现:影响东营组油藏产能下降的因素主要有微粒运移、油水乳化、井筒结蜡及地层水结垢;东营组储层具有中等偏弱—强速敏,速敏伤害主要发生在油井投产早期;建立了反相点与脱水原油50℃下黏度的关系曲线,成功对油井反相点进行了预测;井筒结蜡主要发生在2D井区,表现为产液量突然快速下降甚至出现无产量,清蜡、井筒加热后产能快速恢复;当修井液或注入水与地层水混合之后易形成Ca CO3垢,以沉降垢为主,总垢随地层水比例的增加呈先增加后降低的趋势,在1:1时垢量最大。Dongying formation of Jinxian 1-1 oilfield in Bohai Bay Basin belongs to conventional loose sandstone heavy oil reser-voir. Although this reservoir is in the early stage of development, production declines quickly in many wells. Aiming at this prob-lem, based on geology research, and by taking the measures of sensitivity experiment, emulsion viscosity variation experiment,scale experiment of injected water and formation water, scanning electron microscope analysis and X radiation diffraction, this pa-per comprehensive analyzes production decline factors and mechanism, and studies all production dynamic data, accordingly, theidentification mark on the production curve is concluded by the combination of dynamic and static data, and corresponding mea-sures are proposed. Experiment and the combination of dynamic and static data show that, the main factors influence production re-duction of Dongying formation are particle migration, oil and water emulsification, wellbore wax deposition and formation water scal-ing. Dongying formation has medium weak to strong velocity sensitivity, and velocity sensitivity damage mainly occurs in early pro-duction. The viscosity curves of inverted point and dehydrated crude under the temperature of 50 ℃ are established, which success-fully predict inverted point of oil wells. Wellbore wax deposition mainly occurs in 2 D well field, so liquid producing capacity de-creases rapidly and even shows no production, however, after paraffin removal and wellbore heating, the production regains rapidly.When workover fluid or injected water mixes with formation water, Ca CO3 scale is formed. The content of settlement scale as well astotal amount of scale increases first and then decreases with the increasing volume of formation water, and reaches the maximumwhen the amount of scale is 1︰1.

关 键 词：产能下降 疏松砂岩 微粒运移 油水乳化 金县1-1油田 

分 类 号：TE345[石油与天然气工程—油气田开发工程]