以茶皂苷为原料的煤层气储层泡沫压裂用起泡剂

Foaming Agent for Foam Fracturing of Coalbed Methane Reservoir with Tea Saponin as Raw Material

郗宝华 刘东娜

XI Baohua LIU Dongna

泡沫压裂是煤层气储层压裂增产改造中常用的一种技术手段，起泡剂的选择尤为重要。为了研究出泡沫性能更好、成本更低以及综合性能优良的起泡剂，以茶皂苷、烯基琥珀酸酐和亚硫酸氢钠为原料，通过酯化和磺化反应制备了起泡剂（HBS-J），通过红外光谱表征了HBS-J 的结构，评价了HBS-J 的起泡性、耐盐耐油性、表面活性和储层保护性等。结果表明，HBS-J 的起泡性能、耐盐耐油性能和表面活性均较好。当 HBS-J 的质量分数为0.3%时，起泡体积为590 mL，泡沫半衰期为2562 s，泡沫综合指数可以达到25 193 mL·min，发泡能力和泡沫稳定 性均较强；当盐水溶液中Na+、Ca2+、Mg2+质量浓度分别为79 310、5405、2021 mg/L 或者煤油体积分数达到25%时， HBS-J 仍能形成比较稳定的泡沫体系，并且其起泡能力和耐盐耐油能力均明显优于传统起泡剂（十二烷基硫酸钠、α-烯烃磺酸钠、椰油酰胺丙基甜菜碱）。当HBS-J 的质量分数为0.25%～0.35%时，溶液的表面张力（约40 mN/m）较低。HBS-J 的储层保护性能良好，对煤层基质渗透率的伤害率小于 10%，在泡沫压裂施工过程中不会对煤层气储层造成严重的伤害。HBS-J满足煤层气储层泡沫压裂施工对起泡剂综合性能的要求。

Foam fracturing is a common technical mean in the fracturing and stimulation of coalbed methane reservoir. The selection of foaming agent is particularly important. In order to develop a foaming agent with better foam performance，lower cost and excellent comprehensive performance，the foaming agent（HBS-J）was prepared from tea saponin，alkenyl succinic anhydride and sodium bisulfite by esterification and sulfonation. The structure of HBS-J was characterized by infrared spectrum，and then the foaming property，salt and oil resistance，surface activity，and reservoir protection of HBS-J were evaluated. The results showed that HBS-J had good foaming performance，salt and oil resistance，and surface activity. When the mass fraction of HBS-J was 0.3%，the foaming volume was 590 mL，the half-life of foam was 2562 s，and then the composite index of foam could reach 25 193 mL min，indicating strong foaming ability and foam stability. When the mass concentrations of Na+，Ca2+ and Mg2+ in brine solution were 79 310，5405 and 2021 mg/L respectively or the volume fraction of kerosene reached 25%，HBS-J could still form a relatively stable foam system. Furthermore，its foaming ability and salt and oil resistance were significantly better than those of traditional foaming agents，such as sodium dodecyl sulfate，sodium α-olefin sulfonate，coconut amidopropyl betaine. When the mass fraction of HBS-J was 0.25%—0.35%，the surface tension of solution（about 40 mN/m）was relatively low. The reservoir protection performance of HBS-J was good. The damage rate to the permeability of coalbed matrix was less than 10%. It would not cause serious damage to the coalbed methane reservoir during foam fracturing construction. HBS-J met the requirements of coalbed methane reservoir foam fracturing construction on the comprehensive performance of foaming agent.

10.19346/j.cnki.1000-4092.2024.04.006