耐高温石墨颗粒-凝胶复配调剖剂研制及性能评价

Development and Performance Evaluation of Graphite Particle-Gel Complex Profile Control System

为了获得适用于稠油油藏蒸汽驱的调剖剂,首先通过改性在NH-1主剂（芳香族羟基羧酸盐）分子苯环上引入了硝基得到了改性NH-1主剂,再与助凝剂BK-A05（HPAM）以及交联剂I（酚类）交联剂II（醛类）混合得到可形成空间网状四元共聚凝胶的凝胶体系,并与耐高温石墨颗粒复配,研制了一种耐高温颗粒-凝胶复配调剖体系,并研究了该复配调剖体系的适应性、高温封堵性、耐冲刷性和热稳定性。结果表明：配方为0.025%助凝剂BK-A05＋2.2%交联剂I＋1.8%交联剂II＋8%改性NH-1主剂（NH-主剂与65%浓硝酸按固液比1∶6反应制得）＋0.7%石墨颗粒（10000目）＋0.3%悬浮剂CMC的石墨颗粒-凝胶复配体系的成胶黏度可达2×106m Pa·s,成胶温度范围广（160数280℃）,耐温300℃,适用p H值范围6数8、碱性水矿化度在8000 mg/L以下的地层条件。该复配体系的注入性能良好、封堵率高,对水测渗透率900×10-3μm2的岩心的封堵率在99%以上;此外,复配体系的耐冲刷性和热稳定性良好,30 PV、300℃蒸汽高速冲刷后封堵率仅下降0.35%,300℃下老化50 d后的封堵率仅下降1.63%。复配体系的耐冲刷性和热稳定性效果明显优于单独凝胶体系。

in order to obtain the Profile Control System suitable for Heavy Oil Reservoir Steam Drive, firstly, the traditional high temperature resistant main agent, NH-1 main agent （aromatic hydroxy carboxylate）, was modified though introducing the substituent nitro-group in the benzene ring of NH-1 main agent to improve the heat-resistant ability; secondly, quaternary copolymer gel solution was developed by mixing the modified NH-1 main agent with the coagulant aids and two different cross-linking agents; thirdly, graphite particle-gel complex profile control （GPGCPC） system was obtained by combining the gel solution with graphite particles. The adaptability, plugging ability, anti-scour ability and heat stability of the GPGCPC system were evaluated. Experimental results showed that the formula of the GPGCPC system was as follows, 0.025% Coagulant BK-A05＋ 2.2% cross-linking agent Ⅰ ＋ 1.8% cross-linking agent Ⅱ＋8% modified NH-1 main agent （developed at 1：6 mass ratio of NH-1 to nitric acid with fraction of 65%）＋0.7% graphite particles （10000 mush）＋0.3% suspending agent CMC. The gel-forming viscosity of the gel solution was up to 2× 10^6 mPa.s, and the gel-forming temperature ranged from 160℃ to 280℃ ; the gel solution was heat-resistant to 300℃, applicable to the formation of pH = 6-8 and the alkaline water salinity limit was 8000 mg/L. The Injectivity of the GPGCPC system was good; the plugging rate of the GPGCPC system on the cores with water permeability of 900 ×10^-3 μm2 was more than 99%. In addition, the anti-scour ability and heat stability of the GPGCPC system was excellent, the plugging rate of the cores only decreased by 0.35% and 1.63%, respectively, after 30 PV high-speed steam （300℃） scouring, and the thermostability test at the temperature of 300℃for 50 days, respectively, which was obvious stronger than that of the single gel system.