朝阳沟油田超前注水技术研究与应用
发布时间：2018-06-07 04:55
本文选题：特低渗透油田 + 超前注水 ； 参考：《东北石油大学》2017年硕士论文
【摘要】：朝阳沟油田是典型的低-特低渗透裂缝性油藏,储层渗流阻力大,压力传导能力差,具有一定的压敏特性,投产后油井递减速度快,注水受效慢。目前探明未动用的储量以及待提交储量,主要以低、特低渗透欠压油藏为主,进一步加大了油田开发的难度。超前注水开发方式能合理补充地层能量,提高地层压力,防止储层渗透率损失,建立有效的驱动体系,从而提高油井生产能力并减小递减速度,是一种有效的低渗透油田开发方法,对朝阳沟油田提高水驱开发效果具有重要意义。为此,对超前注水提高产油量机理、超前注水技术界限及后期调整对策,做了进一步的研究。超前注水技术改善开发效果机理:超前注水能够提高地层压力,减少压敏伤害;超前注水有利于建立驱替压力系统,提高原油产量;超前注水有利于提高波及系数和驱油效率,提高采收率。超前注水开发低渗透油藏应用技术界限研究。适应油藏地质条件:压力系数小于0.96的油藏、渗透率小于15mD、流度在0.16~0.60 mD/mPas的油藏建议采用超前注水方式开发,及时补充地层能量;渗透率大于15mD、流度大于0.60 mD/mPas的油藏在通过井网优化、储层整体改造、精细分层注水,可以不采用超前注水,但建议采取同步注水方式开发,防止由于渗透率损失影响开发效果。超前注水技术相关参数界限:一是超前注水阶段合理的地层压力保持水平为原始地层压力的120%左右;二是渗透率越低,达到相同地层压力所需注入孔隙体积倍数越大,当渗透率为7mD时,达到原始地层压力120%时,需要注入孔隙体积倍数0.015PV;三是根据引起速敏的临界流速,计算了长10区块和朝86区块的临界注水强度,为4.0m~3/d·m;四是计算了长10区块和朝86区块合理注水强度为2.0~3.5m~3/d·m,超前注水时间4~6个月。在长10区块及朝86区块开展的超前注水开发现场试验,取得了不错的开发效果:一是井区保持较强的吸水能力,能够满足超前注水需要;二是地层压力保持较高水平,能够建立有效驱动体系;三是单井产量高,递减幅度较小;四是两类油层动用状况较好;五是与同步注水相比,阶段采出程度高,经济效益好。分析研究了开发5年后超前注水井区的宏观及微观开发规律,综合考虑井区累计注水量及井区含水等因素,确定了超前注水井区的调整对策及方式,注水强度调整到1.5m~3/d.m及短周期间注两种调整手段。其中对累注水高于2.5×104m~3进行短周期间注,阶段采出程度比基础方案高0.67个百分点,含水低14个百分点;对注水强度高的井区,进行短周期间注及水量下调方案,使注水强度调整到1.8m~3/d.m。
[Abstract]:Chaoyang Gou Oilfield is a typical low to very low permeability fractured reservoir with large percolation resistance, poor pressure conductivity and certain pressure-sensitive characteristics. After putting into production, the oil well decreases rapidly and the water injection efficiency is slow. At present, the proven reserves and reserves to be submitted are mainly low, ultra-low permeability and under-pressure reservoirs, which further increase the difficulty of oilfield development. Advanced water injection development can reasonably replenish formation energy, increase formation pressure, prevent reservoir permeability loss, establish effective driving system, and thus increase oil well productivity and decrease decline rate. It is an effective method for the development of low permeability oil fields, which is of great significance to improve the development effect of water drive in Chaoyang Gou Oilfield. Therefore, the mechanism of oil production, the technical limits of advanced water injection and the adjustment countermeasures in the later period are further studied. Advanced water injection technology can improve the mechanism of development effect: advanced water injection can increase formation pressure and reduce pressure sensitivity damage; leading water injection is conducive to establishing displacement pressure system and increasing crude oil production; leading water injection is conducive to improving sweep efficiency and oil displacement efficiency. Increase oil recovery. Study on the technical limits of low permeability reservoirs developed by water injection ahead of time. Suitable for reservoir geological conditions: reservoirs with pressure coefficient less than 0.96, permeability less than 15mD, mobility at 0.16m 0.60 mD/mPa?s should be developed by advanced water injection, and the formation energy should be replenished in time. In reservoirs with permeability greater than 15mDand mobility greater than 0.60 mD/mPa?s, the reservoir can be optimized by well pattern optimization, the reservoir is reformed as a whole, and fine stratified water injection can not be adopted. However, it is suggested that simultaneous water injection should be adopted to prevent the development effect from being affected by permeability loss. The limits of parameters related to advanced water injection technology are as follows: first, the reasonable level of formation pressure in advance water injection stage is about 120% of the original formation pressure; second, the lower the permeability, the greater the volume multiple of injection pores required to reach the same formation pressure. When the permeability is 7mD, when the original formation pressure reaches 120, the porosity volume multiple is 0.015 PV.The third, the critical water injection intensity of Chang10 block and Chao86 block is calculated according to the critical velocity of velocity. The reasonable water injection intensity of Chang 10 block and Chao 86 block is 2.0~3.5m~3/d m, and the lead injection time is 4 ~ 6 months. Field tests of water injection ahead of Chang10 and Chao86 blocks have achieved good development results: first, the well area maintains a relatively strong water absorption capacity to meet the needs of advanced water injection; and second, the formation pressure maintains a high level. It can set up an effective driving system; third, the single well production is high, the decline range is small; fourth, the production condition of two kinds of oil layers is better; fifth, compared with synchronous water injection, the stage recovery degree is higher, and the economic benefit is good. This paper analyzes and studies the macro and micro development rules of water injection well area after 5 years of development, synthetically considers the factors such as cumulative water injection rate and water cut in well area, and determines the adjustment countermeasures and methods of leading water injection well area. Water injection intensity adjustment to 1.5m~3/d.m and short-week injection two adjustment means. The stage recovery degree is 0.67% higher than that of the basic scheme, and the water cut is 14% lower than that of the basic scheme. For the wells with high water injection intensity, the injection during the short week and the down-regulation of the water quantity are carried out. The water injection intensity was adjusted to 1.8 mb / d.
【学位授予单位】：东北石油大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TE357.6
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本文编号：1989884
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