驱油体系的驱油效率及其在模拟岩芯表面的润湿性研究

为了研究驱油体系在模拟岩芯表面的润湿性，为微重力应用研究提供依据，选择胜利纯梁采油厂c6—41井原油，应用正交实验设计，通过最低瞬时界面张力测定，筛选出阴离子表面活性剂sDc—V、非离子表面活性剂FBB、HPAM和复碱的驱油体系配方．开展室内模拟驱油实验，同时测定驱油体系溶液对模拟岩芯的接触角，并且关联驱油效率和接触角之间的关系，发现驱油效率越高，接触角值越小．

改性聚丙烯酰胺的合成及其溶液性质的研究

部分水解高分子量聚丙烯酰胺（HPAM），因其稀溶液粘度很大，被广泛应用于三次采油中作为“活性水”驱油的粘度调节剂，以提高石油的采收率（EOR）。但HPAM的耐盐性、耐温性和贮存稳定性不好，如在电解质的水溶液中的粘度效应明显降低，这些缺点影响了它的使用效果。改性聚丙烯酰胺的合成是聚合物采油中的重要研究课题。我们合成和表征了端丙烯酰胺基聚（β-胺基丙酸）（AMPAE）和2-丙烯酰胺基十六烷磺酸（AMC _(11)S）两种新型共聚单体，并用无规共聚的方法获得了耐盐性、耐热性和贮存稳定性有不同程度改善的新型改性聚丙烯酰胺。1、端丙烯酰胺基聚（β-胺基丙酸）的合成和结构表征。在加有自由基阻聚剂的惰性溶剂中，以叔丁醇钠为引发剂可使丙烯酰胺发生氢转移聚合反应，合成新型大分子单体端丙烯酰胺基聚（β-胺基丙酸）对所合成的分子单体我们用~1H-NMR和IR进行了表征；用端基滴定法和~1H-NMR法测定了大分子单体的分子量；用~(13)C-NMR和NaoH水解法测定了大分子单体的支化度。2、2-丙烯酰胺基十六烷磺酸（AMC_(16)S）的合成和结构表征。丙烯腈、2-烯烃(L_5-L_(18))和发烟硫作用可合成N-烷基磺酸基取代的丙烯酰胺衍生物。我们用~1H-NMR谱可对1-正十六烯得到的产物进行了表征，确定了该化合物的明确结构式，并首次给出了该化合物的质谱图。酸值，溴值和元素分析的结果与所确定的结构式相符。3、丙烯酰胺、端丙烯酰胺基聚（β-胺基丙酸）和丙烯酸钠三元共聚物（AM-AMPAE-ANa）的合成。表征及其溶液性质。以硫酸亚铁/异丙苯过氧化氢氧化还原引发体系合成了不同组成的AM-AMPAE-ANa无规共聚物。经用乙醇:水（体积比） = 20:1的混合溶剂萃取纯制过的样品用IR、~1H-NMR进行了表征；通过~1H-NMR和滴定法测定了共聚的组成；用粘度法估算了共聚物的表观分子量。溶液性质的数据表明，该共聚物的耐盐性比HPAM的耐盐性有所改善，但在2% Nacl溶液中，它的耐温性能比HPAM的耐温性能差，该共聚物有着好的贮存稳定性。4、丙烯酰胺和2-丙烯酰胺基十六烷磺酸铵共聚物（AM-AMC_(16)SNH_4）的合成，表征及其溶液性质。以硫酸亚铁/异丙苯过氧化氢氧化还原引发体系合成了不同组成的AM-AMC_(16)SNH_4无规共聚物，经乙醇萃取纯制过的样品，用IR、~1H-NMR、~(13)C-NMR和元素分析进行了表征；通过样品的S和N元素的含量计算了共聚物的组成；用光散射法测定了共聚物在溶液中的表观分子量；用透射电镜观察了共聚物在不同溶剂中的形态。实验结果表明，共聚物分子在水溶液中存在着一定程度的疏水基因间的缔合作用。溶液性质的数据可以看出，AM-AMC_(16)SNH_4共聚物有着很高的粘度盐水保留值（BR）且有着良好的耐温性和贮存稳定性，是一种性能较好的新型改性聚丙烯酰胺。

Demulsification of emulsions exploited by enhanced oil recovery system

Experimental data are presented to show the influence of the enhanced oil recovery system's components, alkali, surfactant, and polymer, on the demulsification and light transmittance of the water separated from the emulsions. Among which, the effects of surfactants, polyoxyethylene (10) alkylphenol ether (OP-10) and sodium petroleum sulfonate (CY-1) on emulsion stability, are the strongest of any component, the effects of polymer, hydrolytic polyacrylamide (HPAM) 3530S, on emulsion stability are the weakest. This research also suggests a possible emulsion minimization approach, which could be implemented in refineries utilizing microwave radiation. Compared with conventional heating, microwave radiation can effectively enhance the demulsification rate by an order of magnitude and increase the light transmittance of the water separated from the emulsions. The demulsification efficiency may reach 100% in a very short. time under microwave radiation.

硫酸盐还原菌对水解聚丙烯酰胺黏度的影响

目的:研究硫酸盐还原菌对油田驱油用水解聚丙烯酰胺体系黏度的影响。方法:以油田回注水配制不同分子量的HPAM溶液,考察硫酸盐还原菌在不同分子量聚合物中的生长繁殖情况及对HPAM溶液黏度的影响。结果:中分、高分、超高分HPAM-采出水体系初始黏度为21.7、25.4、38.9mPa·s,低于灭菌处理的23.0、27.8、45.8mPa·s。上述体系黏度在24h内明显下降。SRB的数量也由初始的3.0×103cfu/mL降低至10～102cfu/ml。结论:短期内SRB对高浓度的HPAM降解作用有限。SRB培养物中的Fe2+是造成HPAM黏度下降的主要原因。SRB对HPAM黏度的影响是间接的。

油田采出水中微生物对部分水解聚丙烯酰胺溶液黏度的影响初探

在实验室条件下,研究了油田采出水中常见微生物类群(腐生菌、硫酸盐还原菌、铁细菌、反硝化细菌)对不同分子质量部分水解聚丙烯酰胺(HPAM)溶液黏度的影响.结果表明:腐生菌及反硝化细菌对聚合物黏度的影响很小;硫酸盐还原菌直接利用大分子聚合物的能力十分有限,但其代谢产物可以显著降低聚合物黏度;铁细菌可以利用聚合物生长,是破坏聚合物黏度的主要微生物类群.

耐盐抗温水溶性聚合物AM-NaAMPS-DEAM的合成及性能研究

以丙烯酰胺（AM），2－丙烯酰胺－2－甲基丙碳酸钠（NaAMPS），N，N－二乙基丙烯酰胺（DEAM）为单体，通过在水溶液中自由基引发共聚合，合成出了AM－NaAMPS－DEAM三元共聚物。并对该三元共聚物的聚合物工艺条件，及对产物性能的影响进行了研究。初步考察了该共聚物的耐盐抗温性能。结果表明：采用本工艺可以制备出分子量大于1200万，增粘效果明显，耐盐抗温性能显著优于HPAM的三元共聚物。

Caracterização de poliacrilamida parcialmente hidrolisada em regime concentrado

A partially hydrolyzed polyacrylamide (HPAM) is a copolymer composed of acrylamide and sodium acrylate. Due to its wide range of applications there are different methods for its quantification and characterization in solution systems. Evaluation of C* is important to describe the transition from dilute to semi-dilute, behavior, when the solution will have its characteristic viscosity at concentrations above C*. This dissertation describes the determination of the critical concentration of overlap C* by potentiometry of partially hydrolyzed polyacrylamide - HPAM under acidic conditions. Based on the law of mass action and the proper treatment of the constant of aggregate formation, polymer molecular weight, degree of polymerization and hydrolysis were calculated. The inflection point was determined by the intersection of the resulting equation and mathematical development, statistically satisfy the experimental points relating the number of moles of monomers (n), equilibrium constant of formation of the entanglements (K*), pH, C* and acidity constant of the polymer (Ka). The viscometric parameters of C* showed a percentage difference compared to potentiometers. The results for the determination of C*, and degree of copolymerization molar mass proved to be a simple alternative for the characterization of polymers with protonated monomers and water soluble

Contribuição da poliacrilamida parcialmente hidrolisada em associação com a bentonita em fluidos de perfuração aquosos

In this study, we investigated the effect of addition of partially hydrolyzed polyacrylamide (HPAM) and bentonite in the physicochemical properties of acquous drilling fluids. Two formulations were evaluated: F1 formulation, which was used as reference, containing carboxymethylcellulose (CMC), magnesium oxide (MgO), calcite (calcium carbonate - CaCO3 ), xanthan gum, sodium chloride (NaCl) and triazine (bactericidal); and F2, containig HPAM steady of CMC and bentonite in substituition of calcite. The prepared fluids were characterized by rheological properties, lubricity and fluid loss. Calcite was characterized by granulometry and thermal gravimetric analysis (TGA). The formulation F2 presented filtration control at 93◦C 34 mL while F1 had total filtration. The lubricity coefficient was 0.1623 for F2 and 0.2542 for F1, causing reduction in torque of 25% for F1 and 52 % for F2, compared to water. In the temperature of 49 ◦C and shear rate of 1022 s −1 , the apparent viscosities were 25, 5 and 48 cP for F1 and F2 formulation, respectively, showing greater thermal resistance to F2. With the confirmation of higher thermal stability of F2, factorial design was conducted in order to determine the HPAM and of bentonite concentrations that resulted in the better performance of the fluids. The statistical design response surfaces indicated the best concentrations of HPAM (4.3g/L) and bentonite (28.5 g/L) to achieve improved properties of the fluids (apparent viscosity, plastic viscosity, yield point and fluid loss) with 95% confidence, as well as the correlations between these factors (HPAM and bentonite concentrations). The thermal aging tests indicated that the formulations containing HPAM and bentonite may be used to the maximum temperature until 150 ◦C. The analyze of the filter cake formed after filtration of fluids by X-ray diffraction showed specific interactions between the bentonite and HPAM, explaining the greater thermal stability of F2 compared to the fluid F1, that supports maximum temperature of 93 ◦C.

Uma nova proposta de fluidos de perfuração aquosos à base de polímeros vinílicos e bentonita para poços de alta temperatura e pressão

The advance of drilling in deeper wells has required more thermostable materials. The use of synthetic fluids, which usually have a good chemical stability, faces the environmental constraints, besides it usually generate more discharge and require a costly disposal treatment of drilled cuttings, which are often not efficient and require mechanical components that hinder the operation. The adoption of aqueous fluids generally involves the use of chrome lignosulfonate, used as dispersant, which provides stability on rheological properties and fluid loss under high temperatures and pressures (HTHP). However, due to the environmental impact associated with the use of chrome compounds, the drilling industry needs alternatives that maintain the integrity of the property and ensure success of the operation in view of the strong influence of temperature on the viscosity of aqueous fluids and polymers used in these type fluids, often polysaccharides, passives of hydrolysis and biological degradation. Therefore, vinyl polymers were selected for this study because they have predominantly carbon chain and, in particular, polyvinylpyrrolidone (PVP) for resisting higher temperatures and partially hydrolyzed polyacrylamide (PHPA) and clay by increasing the system's viscosity. Moreover, the absence of acetal bonds reduces the sensitivity to attacks by bacteria. In order to develop an aqueous drilling fluid system for HTHP applications using PVP, HPAM and clay, as main constituents, fluid formulations were prepared and determined its rheological properties using rotary viscometer of the Fann, and volume filtrate obtained by filtration HTHP following the standard API 13B-2. The new fluid system using polyvinylpyrrolidone (PVP) with high molar weight had higher viscosities, gels and yield strength, due to the effect of flocculating clay. On the other hand, the low molecular weight PVP contributed to the formation of disperse systems with lower values in the rheological properties and fluid loss. Both systems are characterized by thermal stability gain up to around 120 ° C, keeping stable rheological parameters. The results were further corroborated through linear clay swelling tests.

Uma nova proposta de fluidos de perfuração aquosos à base de polímeros vinílicos e bentonita para poços de alta temperatura e pressão

The advance of drilling in deeper wells has required more thermostable materials. The use of synthetic fluids, which usually have a good chemical stability, faces the environmental constraints, besides it usually generate more discharge and require a costly disposal treatment of drilled cuttings, which are often not efficient and require mechanical components that hinder the operation. The adoption of aqueous fluids generally involves the use of chrome lignosulfonate, used as dispersant, which provides stability on rheological properties and fluid loss under high temperatures and pressures (HTHP). However, due to the environmental impact associated with the use of chrome compounds, the drilling industry needs alternatives that maintain the integrity of the property and ensure success of the operation in view of the strong influence of temperature on the viscosity of aqueous fluids and polymers used in these type fluids, often polysaccharides, passives of hydrolysis and biological degradation. Therefore, vinyl polymers were selected for this study because they have predominantly carbon chain and, in particular, polyvinylpyrrolidone (PVP) for resisting higher temperatures and partially hydrolyzed polyacrylamide (PHPA) and clay by increasing the system's viscosity. Moreover, the absence of acetal bonds reduces the sensitivity to attacks by bacteria. In order to develop an aqueous drilling fluid system for HTHP applications using PVP, HPAM and clay, as main constituents, fluid formulations were prepared and determined its rheological properties using rotary viscometer of the Fann, and volume filtrate obtained by filtration HTHP following the standard API 13B-2. The new fluid system using polyvinylpyrrolidone (PVP) with high molar weight had higher viscosities, gels and yield strength, due to the effect of flocculating clay. On the other hand, the low molecular weight PVP contributed to the formation of disperse systems with lower values in the rheological properties and fluid loss. Both systems are characterized by thermal stability gain up to around 120 ° C, keeping stable rheological parameters. The results were further corroborated through linear clay swelling tests.