【作者】 魏向博；

【导师】 李小瑞；

【作者基本信息】 陕西科技大学 ， 高分子化学与物理， 2012， 硕士

【摘要】 我国低渗透油气藏具有类别多、含量高、分布广等特点，储量约占探明储量的2/3以上，开发潜力巨大。该类油气田具有储层致密、渗透率低、喉道微细等特征，易发生永久堵塞伤害作用。因此，低渗透油气储层对压裂液体系的性能要求更高，要求压裂液返排能力较好且对储层伤害较小。针对低渗透油气田的上述特征，为改善现有水基压裂液破胶不彻底、不易返排，对储层渗透率的伤害较大等缺陷，本文合成了两种高温延缓型交联剂：有机硼交联剂BOC-1和有机锆交联剂ZOC-1，二者复配制得有机硼锆交联剂BZC-1。相比较现有有机硼、有机锆交联剂，本文在稠化剂种类和交联体系pH值等方面有所改变。分别以聚乙烯醇（PVA）、羧甲基羟丙基胍胶（CarboxymethylHydroxypropyl Guar gum，简称CMHPG）和羟丙基胍胶（Hydroxypropyl Guar gum，简称HPG）为稠化剂，开发了有机硼/聚乙烯醇（BOC/PVA）、有机锆/羧甲基羟丙基胍胶（ZOC/CMHPG）、有机硼锆/羟丙基胍胶（BZC/HPG）交联压裂液体系。同时，研究了不同因素对凝胶性能的影响，并对压裂液进行了室内评价。所得结果如下：（1）BOC-1的最佳合成工艺为：硼砂20%，甘露醇13.5%，水/丙三醇（体积比3:1）混合溶剂65%，NaOH1.5%。pH值9～10，反应温度80℃，反应时间4～5h。ZOC-1的最佳合成工艺为：氧氯化锆8%，甘露醇/乳酸25%，水/丙三醇（体积比3:1）混合溶剂65%，NaOH2%。pH值3～4，反应温度85℃，反应时间4～5h。BOC-1与ZOC-1以质量比1:1复配，搅拌均匀后可制得易破胶、耐高温的有机硼锆交联剂BZC-1。（2）BOC-1、ZOC-1及BZC-1凝胶具有良好的延缓交联性能，延缓交联时间分别可达70～120s、85～125s、80～120s。可通过调节体系温度、pH值及交联比等，控制交联时间和凝胶性能。（3）室内研究了稠化剂浓度、交联比、pH值、温度对凝胶性能的影响，确定了BOC/PVA、ZOC/CMHPG、BZC/HPG压裂液基本配方为：1.5%/0.8%/0.6%稠化剂+1.5%/2%/1.5%交联剂+1.5%/2%/2%pH调节剂%+1%/1%/1%破胶剂+1%/1%/1%黏土稳定剂。（4）参照《SY/T5107-2005水基压裂液性能评价方法》和《SY/T6376-2008压裂液通用技术条件》对三种压裂液体系进行了性能评价，结果表明：BOC/PVA、ZOC/CMHPG、BZC/HPG压裂液体系具有良好的流变性能，耐温温度分别可达95℃、115℃、130℃，对应温度下的剪切表观黏度分别为70～80mPa·s、80～90mPa·s、80～90mPa·s，具有较好的耐剪切性能，携砂性能良好。（5）BOC/PVA、ZOC/CMHPG、BZC/HPG压裂液体系破胶液黏度低，最大黏度分别为6mPa s、4.8mPa s和5.5mPa s；残渣量低，分别为100mg/L、321mg/L和208mg/L；对岩心伤害率低，分别为15.02%、24.51%和20.41%，低于行业标准的规定。（6）BZC/HPG压裂液体系中加入吸附抑制剂，可有效改善有机锆交联剂对储层伤害严重的缺点。兼具BOC/PVA体系耐剪切、对储层伤害小和ZOC/CMHPG体系耐高温的优点，适于低渗透高温深井压裂改造。结果表明，开发的压裂液体系耐温耐剪切性能良好、破胶液残渣量低且对岩心伤害较小，适于高环保要求、不同井深井温的低渗透油气储层压裂改造。更多还原

【Abstract】 The distribution of low permeability oil and gas resources in Chinais more oil and gas, more hydrocarbon reservoir types, wide distributionarea,etc. The reserves accounts for more than two-thirds of the provenreserves, they have great potential for exploitation. The oil and gas fieldhas dense reservoir, low permeability, larynx way subtle features,subject to have permanent jams damage effect. Therefore, lowpermeable oil and gas reservoir has higher requirements on theperformance of fracturing fluid system. Requires the discharge abilityof fracture fluid return is better and less damage to the formation.According to the above characteristics of low permeable oil andgas fields, to improve the defects that existing water-based fracturingfluid can’t gelout completely, can’t easy to backflow, and damage onreservoir permeability is big, two water-based fracturing fluidhigh-temperature delayed crosslinking agent were synthesized: boron-organic crosslinking agent BOC-1and zirconium-organic crosslinkingagent ZOC-1. Boron&zirconium-organic crosslinking agentBZC-1were blended with both BOC-1and ZOC-1. Compared to theexisting organic boron&organic zirconium crosslinking agent, we’vedone some improvement on thickener types and crosslinking system pHvalue. Using polyvinyl alcohol (PVA) respectively, carboxymethylhydroxypropyl guar gum (CMHPG) and hydroxypropyl guar gum (HPG)as thickening agent, developed organic boron/polyvinyl alcohol(BOC/PVA), organic zirconium/carboxymethyl hydroxypropyl guargum (ZOC/CMHPG), organic boron zirconium/hydroxypropyl guar gum(BZC/HPG) crosslinked fracturing fluid system. At the same time, thispaper studies the different factors on the performance of thecrosslinking frozen glue, and evaluates the fracture fluid in laboratory. The results are as follows:(1) The best synthetic process of BOC-1:20%of borax,13.5%ofmannitol,65%of water/glycerin（3:1volume ratio）,1.5%of NaOH，pH value9～10， reaction temperature80℃, reaction time4～5h.The best synthetic process of ZOC-1:8%of zirconium oxychloride,25%of mannitol/lactic acid，65%of water/glycerin（3:1volume ratio）,2%of NaOH， pH value3～4, reaction temperature85℃, reaction time4～5h.The mass ratio of BOC-1and ZOC was1:1, compound them andadd special absorption inhibitors, stir and get easy gel breaking, hightemperature resistant organic boron zirconium crosslinker BZC-1.(2) BOC-1, ZOC-1and BZC-1crosslinked gel have good delaycrosslinking properties, delay crosslinking time can be up to70～120s、85～125s、80～120s respectively. We can control crosslinking time andfrozen glue performance by adjusting the system temperature, pH valueand crosslinking ratio, etc.(3) In laboratory, we studied influence of the thickener amount,crosslinkeing ratio, pH value and temperature on crosslinking frozenglue,determined the basic formula of BOC/PVA, ZOC/CMHPG andBZC/HPG fracturing fluid system:1.5%/0.8%/0.6%thickener+1.5%/2%/1.5%crosslinking agent+1.5%/2%/2%pH regulator+1%/1%/1%gel breaking agent+1%/1%/1%clay stabilizer.(4) With reference to “the SY/T5107-2005water-based fracturingfluid performance evaluation method "and" SY/T6376-2008fracturingfluid general technology conditions”, the performance evaluationresults of the three kinds of fracturing fluid system show that:BOC/PVA, ZOC/CMHPG and BZC/HPG fracturing fluid system havegood rheological properties, the best temperature is up to95℃,115℃and130℃respectively, the apparent shear viscosity undercorresponding temperature is respectively70～80mPa·s,80～90mPa·sand80～90mPa·s, had better resistance to shear performance, goodproppant carrying capacity.(5) BOC/PVA, ZOC/CMHPG and BZC/HPG fracturing fluid system have low gel breaking liquid viscosity, the biggest viscosity isrespectively6mPa s、4.8mPa s and5.5mPa s, low resikual volume,is respectively100mg/L,321mg/L and208mg/L, low core damage, is15.02%,24.51%and20.41%respectively, lower than theindustry-standard requirements.(6) By using composite inhibitor adsorption and special gelbreaking agent,BZC/of HPG fracturing fluid system combines theadvantages of BOC/PVA and ZOC/CMHPG fracturing fluid system,suitable for low permeability of the high temperature deep wellfracturing transformation.The results show that, the newly developed fracturing fluid systemhave good resistence of heat and shear, low glue residue, and low coredamage. It’s suitable for high environmental requirements and lowpermeability of deep well of oil and gas reservoir fracturingtransformation with different well depth and well temperature.更多还原