HGA1聚合物的酸液性质研究

HGA-1聚合物由于具有特殊的分子结构,因此具有较好的酸液性质.该聚合物在不同的酸浓度、温度下,粘度下降幅度小,并且具有较好的时间稳定性.随着Ca2+浓度的增加,体系粘度明显降低;具有较好的变粘酸性、抗温性、抗酸性,与其他酸液具有较好的配伍性,对油气藏不会造成二次损害.     

A salt-induced viscosifying smart polymer for fracturing inter-salt shale oil reservoirs

Inter-salt shale oil reservoirs located between two salt layers are always accompanied by high temperature and high salinity. However, the present commonly used water-soluble polymers in fracturing fluids su er from poor tolerance to high temperature and high salinity. Thermoviscosifying polymers(TVP) whose aqueous solution shows viscosity increase upon increasing temperature and salt concentration have received considerable attention recently, which is promising for utilization in fracturing fluids to overcome these problems. In this work, both the salt-induced viscosifying property and mechanism of a TVP solution were investigated and the performance of TVP used as fracturing fluid based on the conditions of the Jianghan inter-salt shale oil reservoir in China was evaluated. It is found that the salt-induced viscosifying property of the TVP solution decreases with temperature and shear rate, but increases with polymer concentration. The number of intermolecular hydrophobic domains increases with the salt concentration contributing to the strengthening of a 3D network structure, which results in an increase in viscosity. In addition, the TVP fracturing fluid formulated with saturated brine exhibits excellent temperature and shear resistance, sand-suspending performance, and gel-breaking performance. Its viscosity remains above50 m Pa s after being sheared for 1 h even at a high temperature of 140 °C and the sand-suspending stability can be maintained for more than 1 week at 100 °C. Furthermore, the fracturing fluid can be easily broken down within 12h using 0.2 wt%–0.3 wt% potassium persulfate without residue.     

VES自转向盐酸液变粘特性研究

实验研究了未指名孪二连型粘弹性表面活性剂(VES)自转向盐酸液的变粘特性。5%VES HCl CaCl2模拟酸液的粘度在pH值高于-0.57后迅速上升,pH值1~2时有最大值,这与前人的实验结果略有不同。将2%~6%VES 1%HCl 18.25?Cl2模拟酸液的pH值调至~2,得到的凝胶粘度随VES浓度增大而增大,随温度升高(25~70℃)经历不同的极大值(30~50℃)。5%VES 20%HCl酸液与CaCO3完全反应、pH升至4~5时,形成的凝胶粘度也随温度升高而经历极大值(67℃),但在30~40℃区间粘度急剧波动。G′和G″的频率关系曲线表明0.1%HCl 5%VES 18.25?Cl2模拟酸液的弹性和粘性均大于含0.01%和1.0%HCl的模拟酸液。pH值改变(0.17~13.0)不会使6%VES溶液增粘;加入56~219 g/L CaCl2不会使20%HCl 6%VES酸液增粘;加入3.4mol/L Na 并调pH值至中性或加入2.3 mol/L Ca2 并调pH值至弱酸性,使0.1%HCl 5%VES酸液粘度增大至78~80 mPa.s;因此同时加大pH值和阳离子(Ca2 或Na )浓度,才能使VES酸液增粘。图7表2参10。     

智能转向酸化的机理及试验研究

为了解决在常规酸化中高渗透层的指进、酸液的穿透深度小和残余伤害严重等问题,提出了一种新型的智能转向酸化技术,该酸液体系以粘弹性表面活性剂(visco-elastic surfactants简称VES)和盐酸或土酸为主体外加各种添加剂,在酸化过程中主要依赖于粘弹性表面活性剂的特殊性能实现转向、破胶、缓速降滤的功能,同时具...     

油田污水注聚粘度影响及缓蚀剂的增粘作用

研究了油田污水注聚中配制聚丙烯酰胺（HPAM）溶液时Fe2＋浓度、溶解氧及钢铁腐蚀等因素对溶液粘度的影响。结果表明,水中Fe2＋和溶解氧是引起污水注聚粘度下降的主要因素,溶解氧导致污水管线钢的腐蚀将极大降低注聚粘度。配制的抗氧缓蚀剂有较好的缓蚀和增粘效果,30m（L时的腐蚀速率低于0．076mm／a,100mg／L时的增粘率可达93％。     

新型抗高温抗盐钻井液增黏剂PADA的制备与性能

以2-丙烯酰胺基-2-甲基丙磺酸(AMPS)、N, N-二甲基丙烯酰胺(DMAM)和丙烯腈(AN)为共聚单体,失水山梨醇单油酸酯(Span80)和聚氧乙烯失水山梨醇单油酸酯(Tween80)为复配乳化剂,白油为油相,NaHSO₃ 和(NH₄)₂S₂O₈为氧化还原引发剂,通过正交试验,反相微乳液聚合法制备了增黏剂AMPS-DMAM-AN三元共聚物(PADA)。利用傅里叶变换红外光谱(FT-IR)和热重分析(TGA)研究了PADA的结构和热稳定性,评价了PADA在钻井液中的增黏、降滤失性能。结果表明,增黏剂PADA具有良好的热稳定性,能有效提高淡水钻井液和饱和盐水钻井液的黏度,并降低滤失量,高温老化前后各参数变化不大,抗高温抗盐性能优异。因此,该增黏剂有望在高温地层、盐膏地层的深井钻探中得到应用。     

抗高温钻井液增黏剂的研制及应用

以N-乙烯基己内酰胺为温敏性单体,对苯乙烯磺酸钠为亲水性单体,N,N-亚甲基双丙烯酰胺为交联剂,采用自由基胶束乳液聚合法研制出了一种抗高温钻井液聚合物增黏剂.通过正交试验确定了最佳合成条件,借助元素分析、凝胶色谱分析、热重分析和急性生物毒性实验分别表征了该增黏剂的元素组成、相对分子质量、热稳定性和EC₅₀值,研究了其在水基钻井液中的增黏性能及温敏特性,探讨了增黏机理,优化出了一套适用于环渤海湾地区的可排放水基低密度抗高温钻井液体系,并进行了现场试验.结果表明:该聚合物增黏剂具有优异的增黏性能、热稳定性及温敏特性,在淡水基浆和盐水基浆中经220℃、16h老化后的表观黏度保持率分别为90.81% 和95.95%,EC₅₀值为15.529×10⁴mg/L,满足可排放海水基钻井液技术要求;新研制出的聚合物增黏剂在环渤海湾地区冀东油田深部潜山储层现场的成功应用表明该处理剂能够在深部超高温地层、低膨润土含量及低密度钻井液体系中有效发挥增黏作用,同时也有效地解决了以大量消耗常规磺酸盐共聚物等钻井液处理剂为代价的钻井液日常性能维护问题.     

Effect of inorganic salts on viscosifying behavior of a thermoassociative water-soluble terpolymer based on 2-acrylamido-methylpropane sulfonic acid

The effect of different inorganic salts on aqueous solution viscosifying behavior of a thermoassociative water-soluble terpolymer, poly(acrylamide-co-2-acrylamido-2-methylpropane sulfonic acid)-g-poly[acrylamide-co-N-(1,1-dimethyl-3-oxobutyl)acrylamide] (PADAS) was examined in comparison with a nonthermoassociative sulfonated copolymer, poly(acrylamide-co-2-acrylamido-2-methylpropane sulfonic acid) (PAMS). With increasing salt concentration, thermoviscosifying ability of PADAS was clearly evidenced and the magnitude of thermoviscosifying effect was largely enhanced. The ability of cations and anions to enhance the viscosity of PADAS aqueous solution follows the orders Na⁺ > K⁺ > Mg²⁺ > Ca²⁺ and SO₄²⁻ > Cl⁻ > Br^- > NO₃⁻, respectively. Under the same conditions, PAMS shows only thermothinning behavior and viscosity loss. The thermoviscosifying capability of PADAS is relevant to the change in the polarity of aqueous solution and the electrostatic shield effect of counterion for the repulsion between the sulfonate anions on the polymer, and depends mainly on the competition of these two effects. Cryo-TEM observation demonstrates that the microstructure changes of polymers in the electrolyte solution lead to the changes of the viscosifying behavior. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

新型增稠酸的配方及性能研究

胶凝酸和控滤失酸中均含有合成聚合物，致使在使用中存在返排困难、聚合物残余物质在地层滞留等问题。为获得具有良好缓速性能的清洁稠化酸，采用具有特殊结构的阳离子表面活性剂和有机金属化合物配制出了高黏度的盐酸溶液，研制出了与该体系具有优良配伍性的缓蚀剂，考察了酸液组成对酸液性能的影响。在此基础上提出了用于碳酸盐岩地层酸化作业的FL增稠酸酸液配方，评价了FL增稠酸的基本性能。研究结果表明，该酸液组成具有良好的剪切稳定性，对钢材腐蚀性小，与大理石的反应速度慢，其黏度随温度升高而下降。组成为4%FL4-22＋2% FL4-22A＋20%盐酸溶液＋2%缓蚀剂的酸液在90 ℃下黏度可达25 mPa·s，与地层岩石反应时具有黏度先升后降的特征，残酸黏度低，易于返排，可用于碳酸盐岩地层的深部酸化作业。