油藏深部调剖用聚合物弱凝胶的研究

发布时间：2018-02-12 07:11

本文关键词： 羧甲基纤维素钠黄原胶弱凝胶高温高矿化度　出处：《武汉工程大学》2015年硕士论文　论文类型：学位论文

【摘要】：随着采油技术的发展,在提高采收率方面,聚合物弱凝胶深部调剖技术的应用取得了显著的效果。然而,常用的弱凝胶深部调剖剂主要是聚丙烯酰胺类的,其在一些特殊条件油藏的应用中,易出现高温下降解,高矿化度下产生沉淀等问题,最终导致调剖失效。因此,向聚合物中引入特殊官能团、设计聚合物分子结构,研制具备良好增黏性、耐温性、抗盐性和抗剪切能力的改性高分子聚合物已成为当前研究的热点。目前,交联聚丙烯酰胺类共聚物的出现,一定程度上改善了其抗温抗盐性的不足,但是所用的有机交联剂如甲醛、苯酚或无机交联剂重铬酸钾、柠檬酸铝等对会对环境均造成不同程度的污染。因此,亟需寻找一种具备特殊性能且来源广泛对环境友好的新材料,与丙烯酰胺共聚交联形成新型的聚合物弱凝胶深部调剖剂,进一步提高其抗温抗盐能力,扩大其使用范围。而天然高分子价廉易得,具有刚性环状结构和多功能活性基团,可经过化学修饰改性成新材料,广泛应用于日用化工、食品添加剂和建筑材料等领域。近年来,改性天然高分子以其具备刚性基团以及水溶性、高假塑性等特点,在油田调剖的应用受到了广泛关注。本论文的主要工作是基于上述的研究趋势展开,分别以羧甲基纤维素钠(CMC)和黄原胶(XG)为主剂,以N,N’-亚甲基双丙烯酰胺(BIS)为交联剂,与丙烯酰胺(AM)交联共聚,制备CMC/AM/BIS和XG/AM/BIS两种抗高温抗盐型弱凝胶调剖体系。并且开展了一系列的室内研究,讨论了各试剂用量、反应时间、反应温度对成胶体系黏度的影响,通过IR、TG测试验证了共聚物的结构,并模拟地层条件,对两种共聚物弱凝胶进行了抗盐、抗温、抗剪切、突破压力梯度等性能测试,主要取得了以下的研究成果:(1)对比分析CMC与CMC/AM/BIS共聚物弱凝胶红外谱图及对比分析CMC/AM与CMC/AM/BIS共聚物弱凝胶的失重区域与曲线趋势,验证了CMC/AM/BIS共聚物弱凝胶的组成,证明实验成功制得了CMC/AM/BIS交联共聚物;对比分析XG与XG/AM/BIS共聚物弱凝胶红外谱图及对比分析XG/AM与XG/AM/BIS共聚物弱凝胶的失重区域与曲线趋势,验证了XG/AM/BIS共聚物弱凝胶的组成,证明实验成功制得了XG/AM/BIS交联共聚物弱凝胶;(2)CMC/AM/BIS共聚物弱凝胶的最佳成胶条件为:CMC浓度为1.0×104mg/L,AM浓度为4×104mg/L,引发剂浓度为650mg/L,其中(NH4)2S2O8与Na2SO3的摩尔比为1:1,交联剂BIS浓度为25 mg/L,蒸馏水250mL,反应温度40℃,反应时间8h;XG/AM/BIS共聚物弱凝胶的最佳成胶条件为:XG浓度为1.0×103mg/L,AM浓度为2.0×104mg/L,引发剂浓度为420mg/L,其中(NH4)2S2O8与Na2SO3的摩尔比为1:1,交联剂BIS浓度为630mg/L,蒸馏水250mL,反应温度50℃,反应时间8h;(3)CMC/AM/BIS与XG/AM/BIS共聚物弱凝胶在盐浓度为25×104mg/L时,均未出现脱水现象,这两种体系交联共聚物弱凝胶适用的粗盐、MgCl2和CaCl2的浓度范围均为0~25×104mg/L;(4)CMC/AM/BIS共聚物弱凝胶体系可耐受高温120℃,未出现脱水现象,适用于高温油藏深部调剖作业;XG/AM/BIS共聚物弱凝胶可耐受高温140℃,未出现脱水现象,可适用于特高温油藏的深部调剖作业;(5)CMC/AM/BIS体系与XG/AM/BIS体系,均随剪切速率增大,体系黏度相应减小,具备假塑性,经高速剪切后,黏度保持率分别是90.3%和91.6%,具有较强的抗剪切能力;(6)突破压力梯度模拟实验说明,XG/AM/BIS体系弱凝胶强度较大,附着能力较强,突破压力梯度值为0.172 MPa·m-1,CMC/AM/BIS体系弱凝胶强度相对较弱,突破压力梯度值为0.0355MPa·m-1。
[Abstract]:With the development of production technology, in EOR, application of Polymer Weak Gel deep profile control technology has achieved significant results. However, the weak gel is used for deep profile control agent is composed of polyacrylamide and its application in some special conditions in the reservoir, prone to degradation under the high temperature, precipitation problems such as high salinity, resulting in profile failure. Therefore, the introduction of special functional groups to the polymer, the polymer molecular structure design, developed with good viscosity, temperature resistance, salt resistance and shear resistance of the modified high molecular polymer has become a research hotspot. At present, there crosslinked polyacrylamide the copolymer was improved to some extent, the lack of anti temperature and salt resistance, but the organic crosslinking agent such as formaldehyde, phenol or inorganic crosslinking agent, potassium dichromate, citric acid on aluminum will cause different degree of environment The pollution. Therefore, it is very necessary to develop a special performance and have wide sources of environmentally friendly new materials, and the formation of a new type of acrylamide crosslinked polymer gel deep profile control agent, to further improve the heat resistance and salt tolerance ability, expand the scope of its application. While natural macromolecule is cheap, with a rigid ring structure and multi function active groups through chemical modification into new materials, widely used in daily chemical field, food additives and construction materials. In recent years, modified natural polymer with rigid groups and water solubility, high pseudoplastic characteristics, has attracted wide attention in the application of profile control. The main work of this thesis is based on the above research trend, respectively with sodium carboxymethyl cellulose (CMC) and xanthan gum (XG) as the main agent, with N, N '- methylene bisacrylamide (BIS) as crosslinking agent and acrylamide (A M) Crosslinking Copolymerization, preparation of CMC/AM/BIS and XG/AM/BIS two kinds of salt resistance type weak gel profile control system. And carried out a series of laboratory research, discuss the amount of reagent, reaction time, reaction temperature on the gelling effect, the viscosity of the system through the IR TG test to verify the structure of the copolymer. Simulation and formation conditions of two kinds of copolymers of weak gel salt resistance, temperature resistance, shear resistance, the breakthrough pressure gradient test, the main research results are as follows: (1) comparative analysis of CMC and CMC/AM/BIS on the map and weight loss than copolymer region and curve trend analysis, CMC/AM and CMC/AM/BIS spectra of the copolymer of weak gel weak gel infrared, validation of the CMC/AM/BIS copolymer weak gel composition, demonstrated successfully prepared CMC/AM/BIS crosslinked copolymer; comparative analysis of XG and XG/AM/BIS copolymer map and comparative analysis of XG/AM and XG/AM/BIS Polymer Weak Gel infrared spectrum The weight loss area and curve trend of weak gel, verified XG/AM/BIS copolymer weak gel composition, demonstrated successfully prepared XG/AM/BIS crosslinked polymer weak gel; (2) CMC/AM/BIS Polymer Weak Gel gelling conditions for the optimal concentration of CMC was 1 * 104mg/L, AM concentration is 4 * 104mg/L, the initiator concentration is 650mg/L, which (NH4) 2S2O8 and Na2SO3 molar ratio was 1:1, crosslinking agent concentration of BIS was 25 mg/L, distilled water 250mL, reaction temperature 40 C, reaction time is 8h; the best XG/AM/BIS copolymer of weak gel gelling conditions: XG concentration of 1 * 103mg/L, AM concentration is 2 * 104mg/L, the initiator concentration is 420mg/L, which (NH4) 2S2O8 and Na2SO3 molar ratio was 1:1, crosslinking agent concentration of BIS was 630mg/L, 250mL of distilled water, reaction temperature 50 C, reaction time is 8h; (3) CMC/AM/BIS and XG/AM/BIS Polymer Weak Gel in the concentration of salt is 25 * 104mg/L, were not dehydrated, the two A system of crosslinked copolymer of weak gel for salt, the concentration range of MgCl2 and CaCl2 are 0~25 * 104mg/L; (4) CMC/AM/BIS polymer weak gel system can withstand the high temperature of 120 DEG C, not dehydration, suitable for high temperature reservoir deep profile control; XG/AM/BIS copolymer weak gel can withstand the high temperature of 140 DEG C, no dehydration the phenomenon can be deep for ultra high temperature reservoir profile control operations; (5) the CMC/AM/BIS system and XG/AM/BIS system, with the increase of the shear rate, the viscosity decreases, with pseudoplastic, by the shearing, the viscosity retention rate is respectively 90.3% and 91.6%, with strong anti shearing ability; (6) breakthrough the pressure gradient simulation experiments show that the XG/AM/BIS system of weak gel strength, strong adhesion, breakthrough pressure gradient value is 0.172 MPa - M-1, CMC/AM/BIS system of weak gel strength is relatively weak, the breakthrough pressure gradient value is 0.0355MPa m-1.

【学位授予单位】：武汉工程大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TE39;TQ427.26

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