新型聚合物钾盐抑制泥页岩水化的性能与机理

泥页岩水化膨胀是井壁失稳的重要原因。本文通过膨润土压片浸泡与线性膨胀实验、页岩钻屑滚动回收实验以及流变性、滤失性测试,评价了一种新型聚合物钾盐抑制剂聚阴离子纤维素钾（K-PAC）的抑制性能及其对水基钻井液流变性和滤失性的影响。评价结果表明,0.5% K-PAC的抑制泥页岩水化膨胀的性能明显优于5% KCl、2%聚醚胺-D230（PEA-D230）,与0.5%聚丙烯酰胺钾盐（K-PAM）相近;0.5% K-PAC的增黏提切、降滤失性能要优于0.5% K-PAM。通过扫描电镜和X射线衍射分析了K-PAC的抑制机理,结果表明,K-PAC的阳离子部分（K⁺）能够进入膨润土晶层中并置换出水化钠离子,从而起到抑制黏土晶层膨胀的作用;K-PAC的阴离子部分吸附在黏土颗粒上起到护胶、降滤失的作用,二者协同增效,从而起到强抑制作用。由于K-PAC由聚阴离子纤维素和K⁺构成,对环境友好、成本低廉。因此,K-PAC具有成为低成本、环保型、强抑制性的水基钻井液抑制剂的巨大潜力。     

Polyoxyalkyleneamine as shale inhibitor in water-based drilling fluids

According to the conventional evaluation methods of drilling fluids, the inhibitive property of polyoxyalkyleneamine (POAM), which was prepared in the laboratory, to sodium montmorillonite (Na-MMT) was investigated, and the shale cuttings recovery ratio and the rheological properties of drilling fluids were measured before and after adding POAM in several water-based drilling fluids. The results showed that POAM was completely water-soluble, exhibited the superior performance to inhibit the hydration of Na-MMT and reduced the swelling or hydration of shale cuttings effectively. In addition, the determination of the biological toxicity and compatibility of POAM indicated that POAM was low toxic and compatible with other common drilling fluid additives.     

强抑制性水基钻井液的室内实验研究

由于页岩地层水化作用较强,地层极易水化膨胀导致井壁不稳定,大量岩屑分散在钻井液中,引起钻井液流变性能的剧烈变化,井段容易发生井漏、垮塌、缩径等问题。针对这种情况,研发出一种抗高温抗污染的强抑制性水基钻井液体系。通过评价胺类页岩抑制剂UHIB-B和硅酸盐抑制剂Y1,两者的协同作用提高钻井液的抑制性能,并保持着较好的流变性能。该体系抗温达到了120℃,API滤失量小于3 mL,HTHP滤失量小于9 mL,测试其封堵性能时测得钻井液体系侵入沙床深度为1.8 cm,在膨润土以及无机盐的污染下,仍然保持着较好的流变性能,钻井液体系的岩屑回收率达98%,钻井液的防膨率达85%。试验表明,该套体系具有良好的流变性、抑制性及封堵性,抗温性能和抗侵能力优良,适宜在高水敏和易污染等复杂地层中使用。     

页岩气水基钻井液技术分析

页岩地层易水化膨胀,加之我国页岩气储层地廣结构复杂,井下事故频发,目前我国页岩气钻井多采用抑制性好、润滑性强的油基钻井液。但是由于油基钻井液成本高,污染大,而且油基钻井液条件下浅层气井固井难度大,使用油基钻井液钻井,二个界面存在油泥,水泥胶结质量难保证;加之与油基钻井液配套设施不成熟,因此迫切需要研发一种适用于页岩气水平井作业的强抑制高性能低污染的水基钻井液。     

Hyperbranched polyglycerols,obtained from environmentally benign monomer,as reactive clays inhibitors for water‐based drilling fluids

To prevent the degradation of the borehole and also the disintegration and dispersion of drilled cuttings, different shale stabilizing additives are used in water‐based drilling fluids (WBFs). Glycols, poly(ethylene glycol), glycerols, and polyglycerol derivatives, also called polyols, have been used to inhibit shales containing reactive clays in WBF. These additives are normally used in conjunction with KCl to reduce clay swelling and dispersion of drilled cuttings. Highly branched polymers have become an important field in current polymer science. Such materials typically exhibit compact, globular structures in combination with an exceptionally high number of sites with functional groups. They have unique properties that differ significantly from their linear counterparts, and the hyperbranched polyglycerol (hPG) is an important hyperbranched polymer that can be produced from an environmentally benign monomer, the glycerol carbonate. In this article, the clay inhibitive properties of hPG were evaluated by different test methods including bentonite inhibition test, cuttings recovery, and X‐ray diffraction measurements. The results show that the hPG has a great potential to be used as an environmental friendly inhibitor additive in WBFs. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40384.     

Structure and inhibition properties of a new amine-terminated hyperbranched oligomer shale inhibitor

To inhibit the hydration and dispersion of shale in drilling, a new amine-terminated hyperbranched oligomer (HBO-NH₂) shale inhibitor was synthesized. Compared with linear polymer inhibitors and inorganic salts, HBO-NH₂ possessed a unique hyperbranched structure and plenty of amine groups. The characterization of HBO-NH₂ was done through the aid of Fourier transform infrared spectroscopy (FTIR), nuclear magnetic resonance hydrogen spectroscopy, and time of flight mass spectrum. Upon thermogravimetric analysis, HBO-NH₂ demonstrated favorable thermal stability below 180 °C. As a shale inhibitor, the interlayer spacing of wet bentonite treated with HBO-NH₂ was significantly reduced from 1.9070 to 1.3422 nm in X-ray diffraction analysis. The recovery rate of shale cuttings reached the highest (76.85%) at 120 °C, when the concentration of HBO-NH₂ was 3 wt %. Due to the adsorption of protonated primary amine groups on bentonite particles, the zeta potential absolute value of bentonite base slurry was maintained in a relatively low range of 5–10 mV after HBO-NH₂ treatment. Also, FTIR analysis suggested that hydrogen bonds existed between bentonite and HBO-NH₂. In scanning electron microscope analysis, the inhibition of HBO-NH₂ was observed by the curl degree of bentonite. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47573.     

Structure–property relationship of polyetheramines as clay‐swelling inhibitors in water‐based drilling fluids

The influences of structure parameters of polyetheramines as clay‐swelling inhibitors in water‐based drilling fluids on the application performances were studied. Interactions of polyetheramines with clays were investigated through elemental analysis (EA), X‐ray diffraction (XRD), and thermogravimetric analysis (TGA). The results showed that lower molecular weight, hydrophobic oxypropylene segment, and plentiful amino group of polyetheramines favored improvement of inhibitive properties, enhancement of adsorption abilities, and expelling interlayer bound waters of clays (as confirmed by cutting rolling test, bentonite inhibition test, EA, XRD, and TGA studies). Simultaneously, the polyetheramines did not produce adverse effect to filtration control of the drilling fluids. In addition, XRD patterns revealed that these polyetheramines could intercalate into interlayer spaces of clays and display a monolayer arrangement. The corresponding basal spacing of clays was correlated only with molecular weight of polyetheramines. The dense loading of polyetheramines in the interlayer of clays was beneficial in improving inhibitive properties. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

环保型页岩抑制剂壳聚糖铵盐的性能研究

随着页岩水平段长度的增加,页岩层的井壁失稳问题更加突出。页岩极易水化膨胀引起黏土膨胀压力的增加,导致页岩层的井壁失稳。有机胺抑制剂目前是抑制性能最优异的商业化产品,这类抑制剂仍然难以满足钻井的需求。研发高性能页岩抑制剂成为急需解决的技术。采用环保型的大分子壳聚糖铵盐作为页岩抑制剂。壳聚糖铵盐具有优异的抑制性能和配伍性,形成了以壳聚糖铵盐为核心的水基钻井液体系。结果显示,该体系具有优异的流变性能、页岩抑制性能。有望应用于页岩层的钻井施工。     

A new inhibitor of P(AM‐DMDAAC)/PVA intermacromolecular complex for shale in drilling fluids

A new poly(acrylamide‐dimethyldiallyammonium chloride)/poly(vinyl alcohol) [P(AM‐DMDAAC)/PVA, ADVA] intermacromolecular complex inhibitor of shale‐hydrated swelling was studied for its ability to counter well instability. ADVA exhibited excellent inhibitory performance, and the probable inhibition mechanism was determined. The hydrophilic groups in ADVA adsorbed to montmorillonite (MMT) through hydrogen bonding and cation exchange, and the hydrophobic groups isolated water from MMT. ADVA adhered to the MMT and entered the interlayer instead of water due to the PVA structure. ADVA could also form a thin film and reduce the hydrophilic property of the shale core to prevent water from contacting the shale formation. With the structure of poly(acrylamide‐dimethyldiallyammonium chloride) (AD), the complex adsorbed and bridged MMT to reduce the filtration loss of the basic mud after hot‐rolling. This prevented contact of free water from drilling fluids with the shale formation during the drilling process. With these properties, ADVA demonstrated potential application as an inhibitor for use in drilling fluids. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 45584.     

国内外黏土水化抑制剂研究现状与发展趋势

黏土水化抑制剂在钻井液中的添加可有效降低钻井事故发生,但存在效果不明显、抗温性能尚待提高等缺点。本文简述了国内外黏土水化抑制剂研究现状并分析了其发展趋势。从研究历程来看,黏土水化抑制剂大体上经过了从无机离子型向有机铵（胺）型过渡并逐步成熟于聚合物型的过程。从最新研究结果来看,聚醚胺型抑制剂为主流研究对象,由此形成的高性能水基钻井液在国内外广泛应用;超支化聚合物型抑制剂因具有体型结构而具有较好抗温、抗盐性能而颇具发展优势;传统共聚物型抑制剂分子量大,在高温高密度钻井液中难以适用,仍有改进空间。指出了今后发展趋势是充分利用生物质资源,开发绿色、环保高效的黏土水化抑制剂;研究低聚物抑制剂,提高抑制剂的抗温性、普适性和一剂多效性;摆脱传统钻井液处理剂之间化学作用力观念束缚,探索超支化抑制剂的开发,积极有效结合纳米技术与钻井流体之互补点,以促进钻井液及相关技术发展。     

Terminal amine-based hyperbranched polymer-modified metal oxide particles for improving the stability of water-based drilling fluids in interaction with shales

When oil and gas extraction is drilled into water-sensitive shale formations, water intrusion leads to hydration expansion and dispersion of shale clay minerals, which in turn leads to well wall instability. Two nanomaterials, PET and PEF, were synthesized using Hyperbranched polyethyleneimine (HPEI) as shell-coated metal oxide nanoparticles (MONPs), and the nanomaterials were characterized in terms of molecular structure, thermal stability, and particle size distribution. The blocking and inhibition properties of PET and PEF were tested and investigated by analytical methods such as linear swelling experiments, shale rock chip rolling recovery experiments, and American Petroleum Institute (API) filtration loss experiments, the effects of PET and PEF on the rheology and filter loss reduction of water-based drilling fuilds (WBDFs) were also investigated. PET and PEF have good blocking and inhibition properties, which somewhat ameliorate the effect of NPs on the rheology of WBDFs, while significantly improving the stability of shale in WBDFs.     

Structure‐Property Relationships of New Water‐Soluble Grafted Starches with Amphoteric Character

In an attempt to develop an environmentally friendly, multifunctional mud additive for oilfield drilling treatment, new water‐soluble grafted starches with amphoteric character were prepared by grafting the mixed monomer system of 2‐acrylamido‐2‐methyl‐1‐propane sulfonic acid (AMPS) and 2‐(dimethylamino)ethyl methacrylate (DMAEM) onto naturally occurring potato starch, and characterized by IR and composition analyses. Their structure‐property relationships with respect to the hydration suppression of the swellable clay and the control of mud rheology were studied with the help of clay hydration‐swelling test, mud rheology test, and SEM observation. It has been found that the grafting of DMAEM enhances the inhibition effectiveness of clay hydration‐swelling and that the grafting of AMPS increases the viscosity of the treated muds and the tolerance to added salt. Compared with the partially hydrolyzed polyacrylamide with a degree of hydrolysis of 16%, a typical polymeric additive used in current drilling fluids, such grafted starch with suitable grafting percentage and composition has some distinct advantages in the formulation of water‐based drilling muds.

Swelling percentage (S_p) of the clay pellets as a function of hydration time (t) in water and various sample solutions.     

Hydrophobic-associated polymer-based laponite nanolayered silicate composite as filtrate reducer for water-based drilling fluid at high temperature

Wellbore instability caused by water invasion is the main problem in oil and gas drilling operation. This study reports the utilization of a hydrophobic-associated polymer-based laponite nanolayered silicate composite as a filtrate reducer in water-based drilling fluids (WDFs). The thermal performance and micromorphology of the composite were analyzed by thermogravimetric analysis, transmission electron microscope, and field emission scanning electron microscopy. The results indicated that the composite possessed a “bean pod” structure and a good thermal stability. The rheological properties of the composite solution were evaluated. The results showed that the hydrophobic association interaction of the composite is weak but existent, and the crosslink network structure is variable. The applied performances of WDFs containing the composite were also evaluated. Evaluation results showed that the composite could improve the properties of the thermal stability, salt tolerance, and fluid loss control of WDFs. The particle size distribution of WDFs and the micrographs of filter cakes explained the improving. The composite was expected to be applied as an efficient filtrate reducer for developing high performance drilling fluids. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48608.     

Synthesis of an amphoteric polymer as a high-temperature-resistant shale stabilizer in water-based drilling fluids

To meet the increasing requirement of stabilizing shale under high-temperature situation with the use of water-based drilling fluids (WBDFs), the high-performance shale stabilizer is an urgent need. In this study, an amphoteric copolymer of AM/DMDAAC/NVP (APC) was synthesized by acrylamide (AM), dimethyl diallyl ammonium chloride (DMDAAC), and N-vinylpyrrolidone (NVP) and used as a high temperature-resistant shale stabilizer. The Fourier transform infrared spectroscopy and nuclear magnetic resonance spectroscopy confirmed the successful synthesis of APC. The inhibitive performance of APC was systematically evaluated and compared with three other commonly used shale stabilizers, including the anionic potassium polyacrylamide (KPAM), cationic poly dimethyl diallyl ammonium chloride (PD), and amphoteric polymer FA367. The results demonstrated that APC displayed excellent performance on the linear swelling test, hot-rolling recovery experiment, and shale immersion test. Furthermore, APC combined the advantages of high shale recovery percentages of PD and maintaining shale pellet integrity of KPAM, avoiding the drawbacks of enormous filtration volume of PD and low shale recovery percentages of KPAM. These great properties indicated that APC would be suitable as a shale stabilizer in WBDF to drill high-temperature shale formation.     

Effect of coupling agent on polylactic acid/polypropylene and polylactic acid/polyamide 6 foam composites

The main part of polymer materials generated from fossil fuels do not degrade after completing their usage life and then begin to be waste in the environment. This situation has led to the emphasis on environmentally friendly, biodegradable, and bio-based polymers obtained from renewable sources as an alternative. In recent years, several studies are concentrated on especially lightweight and carbon dioxide (CO₂) emission limitations. In this work, the goal was to investigate at the same time environmentally friendly and lightweight polymer foam composites based on polylactic acid (PLA) polymer without lowering the performances of the materials. In this aim, polymer foam composites containing polypropylene (PP), polyamide 6 (PA6) and PLA were produced (PLA/PA6 (30:70) and PLA/PP (30:70)) with a chemical blowing agent (CBA) introduced at 1.5 wt.% to the polymer mixture. To improve the interpolymer compatibility and foaming activity maleic anhydride-grafted polylactic acid (PLA-g-MA) was utilized as coupling agent (CA) in different ratios (1, 3 and 5 wt.%). From the evaluation of the polymer mixtures in terms of their lightness, thermal and mechanical strength, the most appropriate CA ratios were determined as 1 wt.% for foamed PLA/PP (30:70) mixtures and 3 wt.% for foamed PLA/PA6 (30:70) mixtures.     

Green and self-lubricating polyoxymethylene composites filled with low-density polyethylene and rice husk flour

Polyoxymethylene (POM) composites filled with low-density polyethylene (LDPE) and rice husk flour (RHF) were prepared by injection molding. The POM/5 wt % LDPE/7.5 wt % RHF composite exhibited the lowest wear rate, whereas the coefficient of friction remained low, and the POM/5 wt % LDPE/5 wt % RHF composite had the best mechanical properties. X-ray diffraction analysis was carried out, and the worn surfaces were examined with scanning electron microscopy. The results showed that the addition of the filler reduced the crystallinity degree of the POM composites. The main wear mechanism for unfilled POM was adhesion, whereas for the POM composites, wear seemed to occur mainly by fatigue and abrasion. It was experimentally confirmed that the POM composite filled with LDPE and RHF, which is well-performing, low-cost, and environmentally friendly, could be a potential material for tribological applications. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

Polymers dynamics of the nonfluoro,nano-brush repelling agent with self-stratifying property in water-based coatings

While perfluoroalkyl acids (PFAAs), also known as C8s, are used extensively in textile repellent coatings, concerns have arisen for their carcinogenicity and hazardous effects on the environment. In this study, a novel water-based, nonfluoro, and nanobrush textile repelling agent was prepared by conventional sol–gel chemistry using amorphous fumed silica and n-octyltriethoxysilane as the starting materials. Minimal interaction between the designed repelling agent and marketed water-based resins was confirmed using linear viscosity region (LVR) analysis and asymmetric-flow field-flow fractionation (AF4), suggesting the self-stratification potential of the repelling agent. More specifically, the repelling agent exhibited excellent compatibility and self-stratifying ability with a force-emulsified acrylic-based resin, affording a water contact angle of 104.3° when incorporated at 7% solid content. Performance tests carried out on thermoplastic polyurethane (TPU) revealed excellent adhesion (100/100) of a final formulation, and a significant increase in water contact angle from 80.1° to 103.8° after treatment. In addition, the fouling area after the removal of a submerged sample from a mixture of slurry, polymer, and oil decreased from 48 to 1% when the repelling agent was added. Moreover, the sludge-fouling property remained unchanged after 1000 cycles of abrasion. These findings demonstrate the potential of the described nonfluoro, nanobrush repelling agent as an environmentally safe alternative for use with commercial resins, in turn realizing a fully water-based hydrophobic coating. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 48003.     

页岩气开发钻井液技术研究

由于页岩气井特殊的储层特征,对钻井液的抑制性以及润滑性等提出了很高的要求,油基钻井液虽然能够满足页岩气水平井钻井的需要,但其环保问题以及成本问题等成为制约其大规模应用的瓶颈.为此,针对页岩气储层的特点,室内开展了适用于页岩气水基钻井液的抑制剂、增粘剂、降滤失剂以及润滑剂的优选,形成了一种高性能的页岩气水基钻井液体系.并对该体系进行了综合性能的评价,结果表明,体系具有良好的流变性能,在90 ℃下老化16 h后的高温高压滤失量仅为5.6 mL,摩阻系数为0.11;体系的钻屑热滚回收率达到了98.88%,具有良好的抑制性能;体系在150 ℃高温下老化后仍可保持较好的流变性能和降滤失性能,表明体系具有较强的抗温能力;体系在加入5%的粘土和氯化钠后流变性变化不大,说明体系具有较强的抗污染能力.说明优选的高性能页岩气水基钻井液体系具有优良的综合性能,能够满足页岩气水平井钻井的需要.     

Tensile properties,barrier properties,and biodegradation in soil of compression—Molded gelatin‐dialdehyde starch films

Glycerol (Gly)‐plasticized gelatin (Ge) films crosslinked with dialdehyde starch (DAS) as environmentally friendly crosslinking agent were successfully produced by compression molding, demonstrating the capacity of gelatin of being transformed into films by using thermoplastic processes. The effect of DAS content on the color, light transmission, total soluble matter (TSM), water uptake (WU), water vapor permeability (WVP), oxygen permeability (OP) as well as biodegradability during soil burial was investigated. The addition of up to 10 wt % DAS (Ge‐10DAS) generated transparent films, with reduced TMS, WU, WVP, and OP values but higher extensivity than the uncrosslinked counterpart. Further incorporating DAS into plasticized‐gelatin matrix conducted to phase separation with detrimental effect of transparency and tensile properties. DAS‐containing films degraded at slow rate than the uncrosslinked counterpart, suggesting that biotic attack during soil burial is restricted by covalent crosslinking points induced by DAS. Ge‐10DAS films lost about 28% of their initial mass within the first 8 days of exposure to degrading medium; therefore, the material can be classified as rapidly degradable. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

High-pressure adsorption of methane on montmorillonite,kaolinite and illite

Methane (CH₄) adsorption of Ca^2 +-montmorillonite (Mt), kaolinite (Kaol) and illite (Il) at 60 °C and pressures up to 18.0 MPa was investigated, during which the adsorption capacity was evaluated by the Langmuir adsorption model. The influences of adsorbed water and the interlayer distance of the clay minerals on CH₄ adsorption were explored by using heated Mt products with different interlayer distances as the adsorbent. Mt, Kaol and Il showed high CH₄ adsorption capacities, and their maximum Langmuir adsorption capacities were Mt, 6.01 cm³/g; Kaol, 3.88 cm³/g; and Il, 2.22 cm³/g, respectively. CH₄ was adsorbed only on the external surface of Kaol and Il; however, adsorption also occurred in the interlayer space of Mt, which had a larger interlayer distance than the size of a CH₄ molecule (0.38 nm). CH₄ adsorption in the interlayer space of Mt was supported by the lower CH₄ adsorption capacity of heated Mt products (with the interlayer distance < 0.38 nm) than that of Mt at high pressures despite the higher external surface areas of the heated Mt samples. The entrance of CH₄ into the interlayer space of Mt occurred at low pressures, and more CH₄ molecules entered the interlayer space at high pressures. Moreover, the adsorbed water occupied the adsorption sites of the clay minerals and decreased the CH₄ adsorption capacity. These results indicate that clay minerals play a significant role in CH₄ adsorption of shale and indicate that the structure and surface properties of clay minerals are the important parameters for estimating the gas storage capacity of shale.