环保型强抑制钻井液技术在荣18-3X井的应用

Application of Environment-friendly Strong Inhibition Drilling Fluid Technology in Rong18-3X Well

荣18-3X井为辽河油田一口重点开发井,地层岩性主要为泥岩,夹杂砂岩,钻井过程中存在大段泥岩段井壁稳定性差、定向托压严重等难题,且该井在水库附近,环保要求高。为保证该井钻井液高质量施工,同时达到环保和保护油气层的目的,针对其地质结构特点、技术难点和环保要求,建立了一套环保型强抑制钻井液体系,其基本配方为:8%~10%KCl+0.2%烧碱+0.4%XCD+2%~3%HRL+0.1%~1%PAC-DB+0.1%~0.3%有机胺+2%~3%JWR-1+8%超细碳酸钙+石灰石(看密度)+1%~1.5%润滑剂+0.3%消泡剂,在荣18-3X井进行应用。应用结果表明,该体系抑制性能优良,携岩能力强,抑制防塌效果好,保证了大段泥岩稳定,施工中未发生泥岩井壁失稳的情况,满足了钻井施工要求,为该区块下一步的勘探开发提供了技术支撑。

Rong18-3 X well is a key development well in Liaohe oilfield. The lithology of the formation is mainly mudstone, mixed with sandstone. During the drilling process, there are many problems, such as poor wellbore stability of large section of mudstone, serious directional pressure support and so on. Moreover, the well is near the reservoir, which requires high environmental protection. In order to ensure the high quality of drilling fluid in this well and achieve the purpose of environmental protection and reservoir protection, a set of environmental protection strong inhibition drilling fluid system was established according to the geological structure characteristics, technical difficulties and environmental protection requirements, The basic formula was as follows: 8%~10% KCl + 0.2% caustic soda + 0.4% XCD + 2%~3% HRL + 0.1% ~ 1% PAC-DB + 0.1%~0.3% organic amine + 2%~ 3% JWR-1 + 8% ultrafine calcium carbonate + limestone(apparent density) + 1% ~ 1.5% lubricant + 0.3% defoamer, which was used in sidetracking section of Rong18-3 X well. The application results showed that the system had excellent inhibition performance, strong rock carrying capacity, good inhibition and anti-collapse effect, ensured the stability of large section of mudstone, and no instability of mudstone borehole wall occurred during construction, met the requirements of drilling construction. The paper can provide technical support for the next exploration and development of the block.