A new environmentally friendly water-based drilling fluids with laponite nanoparticles and polysaccharide/polypeptide derivatives

Considering the increasing environmental pressure,environmentally friendly and high-performance water-based drilling fluids(WBDFs)have been widely studied in recent years to replace the commonly used oil-based drilling fluids(OBDFs).However,few of these drilling fluids are entirely composed of natural materials,which makes it difficult to achieve real environmental protection.Using laponite nanoparticles and various derivatives of natu ral mate rials,including cro sslinked starch,cellulose composite,gelatin ammonium salt,poly-l-arginine,and polyanionic cellulose,a kind of environmentally friendly water-based drilling fluid(EF-WBDF)was built for drilling in environment-sensitive areas.The properties of this EF-WBDF were evaluated by thermal stability tests on rheology,filtration,inhibition,and salt contamination.Besides,biological toxicity,biodegradability,heavy mental content and wheat cultivation tests were conducted to investigate the environmental factor of EF-WBDF.Results showed that EF-WBDF displayed satisfactory thermal resistance up to 150℃,and the rheological properties did not suffer significant fluctuation,showing potential application in high-temperature wells.The optimal rheological model of EF-WBDF was Herschel-Bulkley model.This EF-WBDF performed an eligible filtration of 14.2 mL at 150℃and a differential pressure of 3.5 MPa.This fluid could still maintain colloidal stability after being contaminated by 7.5%NaCl or 0.5%CaC1_(2).Meanwhile,rather low clay swelling degree of 2.44 mm and high shale recovery of more than 95%ensured the inhibitive capability of EF-WBDF.Furthermore,EF-WBDF presented a half maximal effective concentration(EC_(50))of51200 mg/L and a BOD/COD ratio of 47.55%,suggesting that EF-WBDF was non-toxic and easily biodegradable.The wheat cultivated in EF-WBDF could grow healthily,beneficial for reducing the adverse impact on ecological environment.The formed EF-WBDF has a promising future for drilling in environment-sensitive and high-temperature areas.

Performance Analysis of a Profile Control Agent for Waste Drilling Fluid Treatment

A method for the treatment of hazardous waste drilling fluids,potentially leading to environmental pollution,is considered.The waste drilling fluid is treated with an inorganic flocculant,an organic flocculant,and a pH regulator.The profile control agent consists of partially hydrolyzed polyacrylamide,formaldehyde,hexamethylenetetramine,resorcinol,phenol,and the treated waste drilling fluid itself.For a waste drilling fluid concentration of 2500 mg/L,the gelling time of the profile control agent is 25 h,and the gelling strength is 32,000 mPa.s.Compared with the profile control agent prepared by recirculated water under the same conditions,the present profile control agent displays better stability,salt-resistance,and performance.

Optimization of Anti-Collapse Drilling Fluid Systems with High Potassium Content

The ash mudstone in some oil formations is highly water-sensitive.The oil formation is fractured,and the risk of well leakage and collapse is not negligible.This study presents a countermeasure for well collapse prevention,based on a“force-chemistry synergistic balance”approach and the utilization of environmentally friendly and efficient hydration inhibitors.The relevance of this approach is demonstrated considering a drilling fluid system with the high potassium content.The analysis shows that the system can maintain good rheological properties,filtration loss and suspension stability even after aging at 130℃ for 16 h.The primary roll recovery of rock chips is better than 98%.The secondary rolling recovery rate is 89%.The rapid water loss is close to zero.The effects of carrying rock,sand,hydration inhibition and dispersion of drill chips are all noticeable.

A Study of Solid-Free Drilling Fluid for Tight Gas Reservoirs

This project is explaining a laboratory development of a solid free drilling fluid formula that could be potentially used in tight gas reservoirs. The configuration of the weak gel fluid WGL-1, which is resistant to high temperature and high salt, was tested, and concluded that its gelling properties, salt and temperature resistance, and environmental protection were all in line with industry requirements. The final drilling fluid formula was developed as: water + (0.3% ~ 0.5%) NaOH + 5% KCl + 2% WGL-1 + 5% NaCl + (1.0% ~ 2.0%) HBFR Anti-high temperature fluid loss agent + 2% Polyol + (1.5% ~ 2.0%) SDL-1 Lubricant + 0.4% A4O1. The performance of the liquid was tested for temperature resistance, inhibition, gas formation protection effect, plugging performance, and static settlement stability. It was concluded that the temperature resistance performance is satisfied at 150°C, and the cuttings recovery rate is as high as 96.78%. It has good performance in inhibiting water dispersion and swelling of cuttings. The permeability recovery value reaches 88.9%, which meets the requirements of gas formation protection. The SSSI value shows that its settlement stability is good;under high temperature and high pressure, its sealing performance is good. This drilling fluid system has achieved the expected results and laid a foundation for further promoting the development of solid-free drilling fluid systems. The future development direction of solid-free drilling fluids is pointed out, to the improvement of properties to be applied in high temperature environment and have high salt resistance capacity.

Research progress and development of deep and ultra-deep drilling fluid technology

The research progress of deep and ultra-deep drilling fluid technology systematically reviewed,the key problems existing are analyzed,and the future development direction is proposed.In view of the high temperature,high pressure and high stress,fracture development,wellbore instability,drilling fluid lost circulation and other problems faced in the process of deep and ultra-deep complex oil and gas drilling,scholars have developed deep and ultra-deep high-temperature and high-salt resistant water-based drilling fluid technology,high-temperature resistant oil-based/synthetic drilling fluid technology,drilling fluid technology for reservoir protection and drilling fluid lost circulation control technology.However,there are still some key problems such as insufficient resistance to high temperature,high pressure and high stress,wellbore instability and serious lost circulation.Therefore,the development direction of deep and ultra-deep drilling fluid technology in the future is proposed:(1)The technology of high-temperature and high-salt resistant water-based drilling fluid should focus on improving high temperature stability,improving rheological properties,strengthening filtration control and improving compatibility with formation.(2)The technology of oil-based/synthetic drilling fluid resistant to high temperature should further study in the aspects of easily degradable environmental protection additives with low toxicity such as high temperature stabilizer,rheological regulator and related supporting technologies.(3)The drilling fluid technology for reservoir protection should be devoted to the development of new high-performance additives and materials,and further improve the real-time monitoring technology by introducing advanced sensor networks and artificial intelligence algorithms.(4)The lost circulation control of drilling fluid should pay more attention to the integration and application of intelligent technology,the research and application of high-performance plugging materials,the exploration of diversified plugging techniques and methods,and the improvement of environmental protection and production safety awareness.

钻井利器的故事之“护壁堵漏材料”

近年来,作为入地最为关键手段的钻探所面临的地层越来越复杂,钻孔垮塌、掉块、缩径和超径等事故发生概率增加,严重制约了钻探工程质量与效率的提升。护壁堵漏材料是钻探工程不可或缺的关键性工程材料,护壁堵漏技术则是保证钻进工作安全、快速以及持续进行的重要技术环节,是复杂地层钻孔处理的主要内容。本文从科普的角度介绍了护壁堵漏材料的基本概念与组成、冲洗液护壁堵漏作用、水泥基材料护壁堵漏作用、护壁堵漏材料的进一步发展空间等,以期加深对护壁堵漏材料的认识,促进新型护壁堵漏材料的研发和应用。

环境友好型水基钻井液GREEN-DRILL的研制与应用

为了提高海上油气田钻井液的环保性能,在开发环保型高效封堵剂GS、水基润滑剂GL和水溶性抑制剂GG的基础上,研制出了环境友好型水基钻井液GREEN-DRILL。性能评价结果表明,水基钻井液GREENDRILL的基本性能稳定,抑制性能与聚合醇钻井液基本相当,其生物需氧量与化学耗氧量的比值为67.5%,对蒙古裸腹溞Ⅰ龄幼体72h半数致死浓度大于60 000mg/L,高于国家一级海域生物毒性容许值,符合国家一级海域排放标准。同时,在水中稀释后无油膜、无黑色漂浮物。渤海油田5井次的现场应用表明,水基钻井液GREENDRILL能解决渤海油田存在的渗漏和井漏问题,性能稳定,环保性能优良。

深层超深层钻井液技术研究进展与展望

系统论述目前国内外深层超深层钻井液技术研究进展,分析存在的关键问题并提出未来发展方向。针对深层超深层复杂油气层钻井过程中面临的高温高压高应力、裂缝发育、井壁失稳、钻井液漏失等问题,国内外学者研发了深层超深层抗高温高盐水基钻井液技术、抗高温油基/合成基钻井液技术、储层保护钻井液技术以及钻井液防漏堵漏技术,但仍存在抗高温高压和高应力能力不足、井壁易失稳以及钻井液漏失严重等关键问题。由此提出未来深层超深层钻井液技术的发展方向:(1)抗高温高盐水基钻井液技术需致力于提升高温稳定性,改进流变性能,强化滤失量控制,提高与地层的相容性。(2)抗高温油基/合成基钻井液技术需在高温稳定剂、流型调节剂等低毒易降解的环保型添加剂和相关配套技术方面进一步攻关。(3)储层保护钻井液技术应致力于新型高性能添加剂和材料的研究,通过引入先进的传感器网络和人工智能算法,完善实时监测技术。(4)钻井液防漏堵漏技术应更加注重智能化技术的集成与应用、高性能堵漏材料的研发与应用、多元化堵漏技术与方法的探索以及环境保护与安全生产意识的提高。

渤海湾钻井液处理剂和钻井液体系生物毒性评价

我国环保形势日益严峻,油气田开发过程中环保压力越来越大,如何确保钻井液处理剂及体系无毒无害环境、环境可接受,最大限度减少钻井废物量,实施废物综合利用,满足钻井工程安全、优质、快速、高效需求,已经成为钻井作业的发展趋势,越来越受到重视。生物毒性检测试验是用于评价某种化学物质或混合物对环境的潜在污染物毒性危害预测的直接手段,室内对渤海湾常用的钻井液处理剂和体系采用发光细菌法进行了生物毒性检测评价,为环保钻井液研究和开发以及处理剂的优选提供了参考和技术保障。

高温环保钻井液研究及其干热岩钻探应用

干热岩是内部无流体或存在少量流体且温度高于180℃的异常高温岩体,是极具潜力的新型清洁能源(毛翔等,2019)。随着我国干热岩钻探工程的逐步开展,钻遇地层的超高温度对钻井液的抗高温能力提出了更高的要求。干热岩钻探中所用的水基钻井液在高温下出现黏度显著增大或减小、滤失量大幅增加等钻井液性能恶化的问题,石油钻井常用抗高温三磺钻井液因其含有的磺酸基团具有一定毒性,会对环境及地层造成污染,不适用干热岩钻井(刘畅等,2021)。

环保型弱凝胶护壁护心钻井液研究与应用

海域浅层气地质调查和盐湖环境科学钻探在松散砂岩钻探取样工程中,存在孔壁易坍塌、成孔率低等技术难题,为此开展了松散砂岩地层环保型弱凝胶护壁护心钻井液技术研究。通过弱凝胶结构研究及成胶剂、交联剂及抗盐降滤失剂等材料优选,研发了一套环保型弱凝胶护壁护心钻井液,评价了钻井液的流变性、滤失性、抑制性、护心性能、环保性能等性能,并在山西某盐湖环境科学钻探工程进行现场应用。室内测试及现场应用结果表明:研制的弱凝胶护壁护心钻井液具有良好的流变性、降滤失性、抑制性(岩屑回收率96.3%)、护壁护心性能及环保性能(BOD5/COD比值24.6%,EC50值47950 mg/L),能有效解决松散砂岩类地层孔壁坍塌、岩屑不易携带等问题,在松散地层钻探工程中具有广阔的应用前景。

胜利油田钻井液环保处理技术研究与应用

在胜利油田钻井过程中,废弃物总量大、污染物含量高,废弃物污染控制集中于末端治理,资源化利用程度低、成本高,无法实现钻井过程中的污染控制,严重影响油田生态环境。针对该油田钻井过程中的环保关键技术难题,以“减量化、无害化、资源化”为目标,进行了理论研究、装备研发、技术攻关和集成应用,形成了钻井污染物源头控制、全井段钻井废弃物随钻过程减量化和钻井废弃物末端无害化处理与资源化利用等3项核心技术,创新了覆盖“源头控制、过程减量、末端治理”的钻井液环保处理技术。“十三五”期间,该钻井液环保处理技术在胜利油区及新疆、四川等地的中国石化工区实现规模化应用,建成了胜利油田滨105、盐222、桩146等绿色低碳钻井示范工程,为保障胜利油田绿色低碳开发提供了技术支撑,也为我国陆上油气田绿色低碳开发提供了有益借鉴。

内蒙古某矿山开采主要污染物治理与环境保护研究

内蒙古某大型铀矿床采用CO_(2)+O_(2)地浸开采技术,以CO_(2)+O_(2)作为溶浸剂配制溶浸液,与矿层中的铀络合生成离子,在井场浸出和浸出液水冶处理过程中产生废井液和工艺废水污染物。在治理污染物的过程中,通过固井、地表固化和回收方式对废井液进行处理;对树脂转型废水进行反渗透处理,将反渗透浓水、树脂反冲废水等排至蒸发池蒸发。研究结果显示,废井液放射性较低,U天然平均浓度为38 mg/L,226Ra活度浓度平均为79 Bq/L。树脂转型水反渗透处理后U天然浓度<0.05 mg/L,226Ra活度浓度<1.1 Bq/L。蒸发池残渣中U天然平均比活度为426.90 Bq/L,226Ra平均比活度696.67 Bq/kg。通过对污染物进行治理,固井、地表固化均符合环保要求,工艺废水和蒸发池残渣符合相关标准要求,为该类型矿山污染物治理提供了方法和思路。通过采用本文方法可以达到污染物治理的目的,保护当地生态环境,产生积极的企业效益和社会效益,为企业高质量发展提供保障。

一种水基钻井液用抗温润滑剂的研制与评价

随着我国地下浅层的油气储量不断减少,油气勘探逐渐转向深层,井下高温高压、高摩阻扭矩等情况都对钻井液润滑性提出了更高的要求。本文以长链脂肪酸和低分子多元醇等为原料,制备了一种高效耐温耐磨的复合润滑剂GWLUB-1,并对其进行了性能评价。评价结果表明:GWLUB-1润滑性能优异,当1%加量时,其在淡水和盐水基浆中的润滑系数降低率分别达到90%和80%以上;加量为2%时,基浆抗磨性能良好,且磨痕低于4 mm,抗磨效果显著;GWLUB-1抗温达180℃,环保无毒;与钻井液体系配伍性良好,应用前景较好。

高原高速公路生态保温型水泥稳定碎石层养生技术研究

高原地区环境脆弱,在这里区域建设高速公路的要求很高,其中水稳基层的养生过程对环境的影响较大,为遴选出更为生态环保的养生技术方案,又要满足性能要求,研究进行了三种养护方式的室内试验和道路施工验证,包括可降解的保湿膜、滴灌节水的保湿养护以及PE薄膜密封养护。结果显示:使用土工布进行养护需要水量大,而且保温性能及对水泥稳定碎石的收缩性抵抗能力最差。PE薄膜密封养护次之,而可降解保湿膜的效果最优。

安全环保的新型水基钻井液ULTRADRILL

针对渤海地区钻进过程中遇阻遇卡 ,起下钻困难 ,密度难以控制 ,机械钻速低等问题 ,采用了安全环保的新型水基钻井液ULTRADRILL ,ULTRADRILL新型钻井液的合成聚合物不含铬及其它对环境有害的物质。该钻井液主要由两种基本的页岩抑制剂和钻速增效剂组成。该钻井液能提供优异的页岩抑制性、润滑性和井眼稳定性 ;滤失量小、滤饼薄 ,可防止钻头泥包 ;携砂能力强 ,流变性易于控制 ;具有较广的密度和盐的选择性。现场应用表明 ,ULTRADRILL钻井液性能稳定 ,具有独特的流变性能 ,滤失量小、泥饼坚韧、致密而光滑 ;钻井过程中悬浮携砂能力强 ,钻速快 ,井壁稳定。该钻井液容易降解 ,且无生物毒性 ,满足了海洋环保的要求。

环保型生物柴油基钻井液体系研究及应用

针对柴油或白油基钻井液环保性能较差以及存在安全风险等问题,以生物柴油为基液,通过研制相应的乳化剂、改性有机土和降滤失剂等主要处理剂,研究出了一种环保型生物柴油基钻井液体系,并对其综合性能进行了评价。结果表明:环保型生物柴油基钻井液体系具有良好的流变性能和稳定的破乳电压,高温高压滤失量低于5 mL,并且具备良好的润滑性能和抑制性能;该钻井液体系具有良好的抗淡水、NaCl、CaSO 4和岩屑污染的能力;此外,钻井液的生物毒性较低,EC 50值大于25000 mg/L,环保性能优良;环保型生物柴油基钻井液体系的综合性能优于常规生物柴油基钻井液。现场应用结果表明,Z-11井三开井段使用环保型生物柴油基钻井液体系钻进,不同井深的现场钻井液性能稳定,可以达到较高的机械钻速,摩阻、扭矩以及钻井周期等工程参数均明显低于使用水基钻井液的邻井,现场返出钻屑中的毒性物质含量低于国家标准要求,不属于危险固体废弃物,不会对环境造成严重污染。

一种环保非水基钻井液体系的构建及其性能评价

为满足日益严苛的环保要求,通过测试乳化剂、内相盐、基液等的生物毒性及降解性,研究植物油酸及其酯类衍生物类乳化剂BIO-EMUL与BIO-COAT复配乳化剂溶液与BIO-OIL形成的油包水乳液的电稳定性、乳化效率以及BIO-EMUL与BIO-COAT复配乳化剂溶液与BIO-OIL间的界面张力和界面流变性,以BIO-EMUL和BIO-COAT为基础,结合基液BIO-OIL以及乙酸钠溶液,构建了一种环保非水基钻井液体系,并研究了该钻井液的基本性能和抗污染能力。结果表明,BIO-EMUL、BIO-COAT能有效降低油/水界面张力,形成破乳电压达350V,乳化效率达95%的油包水乳液。该体系的LC_(50)为28 200 mg/L,BOD_(5)/COD_(Cr)>0.25,是生物毒性低,降解性良好的环境友好型油包水乳液。配制的钻井液体系适用密度范围广,抗污染能力强,为今后环保非基钻井液体系及材料的研究提供了基础。

小井眼提速技术在页岩油开发中的应用

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