碱木素高温堵剂增韧改性实验研究

Toughening Modification of Alkali Lignin High Temperature Plugging Agent

任兴华 齐宁 田壮壮 李振亮 梁冲

REN Xinghua QI Ning TIAN Zhuangzhuang LI Zhengliang LIANG Chong

碱木素堵剂具有优良的耐温耐盐性能，但存在韧性差、易破碎、有效期短等缺点。针对这一问题，通过在常规碱木素堵剂中添加增韧剂以提高体系韧性，研究了碱木素、交联剂与增韧剂各组分加量、pH值、温度、矿化度和反应时间等因素对体系成胶性能的影响，通过测量凝胶体系的模量和红外结构表征考察了堵剂的韧性改善情况，通过填砂管物模实验评价了堵剂的封堵效果。结果表明，配方为6.0%碱木素、5.0%交联剂和0.5%增韧剂韧性改善碱木素高温凝胶在120℃下的成胶时间为8 h、成胶强度为0.048 MPa。该体系可在7~11 pH值范围内成胶，耐盐达20×104mg/L、耐温140℃。凝胶体系的弹性大于黏性，凝胶弹性模量随增韧剂加量的增大而增加。凝胶堵剂封堵能力和耐冲刷性较好，封堵率达97%以上，可以用于高温高盐油田缝洞型油藏调剖堵水作业。图12表6参14

Alkali lignin plugging agent had excellent resistance to temperature and salt，but it had many shortcomings，such as bad toughness，easy to break and short period of validity. In order to improve the toughness of system，the toughening agent was added to conventional alkali lignin plugging agent. The effects of component dosage，including alkali lignin，crosslinking agent and toughening agent，pH value，temperature，salinity and reaction time on the gelling property were studied. The toughness of gel system was evaluated by means of elastic modulus test and infrared characterization. The actual plugging effect was obtained by plugging test with sand filled tube. The results showed that the optimum formula of alkali lignin high temperature gel was obtained as follows：6.0% alkali lignin，5.0% crosslinking agent and 0.5% toughening agent，whose gelation strength was 0.048 MPa and the gelation time was 8 h at 120℃. The gelling pH value of alkali lignin plugging agent system was 7—11，the salt tolerance of that reached to 20 × 104 mg/L，and the temperature resistance of that was 140℃ . The elasticity of gel system was greater than the viscosity，and the elastic modulus of gel increased with increasing concentration of toughening agent. The plugging ability and abrasion resistance of gel plugging agent were good whose plugging rate was above 97%. It could meet the demand of profile control and water shutoff operation in fracture-cavity reservoir with high temperature and high salinity.

10.19346/j.cnki.1000-4092.2018.01.013