地面交联酸酸蚀裂缝导流能力研究

酸蚀裂缝导流能力是影响酸压效果和评价酸液性能的重要指标。根据API行业标准，利用酸蚀裂缝导流装置室内开展了地面交联酸及其闭合酸化后裂缝导流能力的测试。结果表明，闭合压力40 MPa时地面交联酸的酸蚀裂缝导流能力为150 μm2·cm，55 MPa时依然在80 μm2·cm以上；地面交联酸酸压后经过闭合酸化，40 MPa下酸蚀裂缝导流能力为269 μm2·cm，较未闭合酸化前提高了1.7倍；酸岩反应后的溶蚀形态好，沟槽明显，深度多在0.5~4.5 mm，可承载高闭合压力和提高长期导流能力；同时，其导流能力值远高于5级普通酸和5级稠化酸，显示出更为优良的液体性能。

Study on acid etching fracture conductivity of surface cross-linked acid

Acid etching fracture conductivity is an important indicator of affecting acid fracturing effect and evaluating acid fluid performance. According to the API industry standard, fracturing conductivity of surface cross-linked acid and closed acidization laboratory experiments were carried out using etching fracture conductivity device. The results show that the fracture conductivity of surface cross-linked acid was 150 μm2.cm under 40 MPa closing pressure, and still higher than 80 μm2.cm when closing pressure up to 55 MPa; Surface cross-linked acid fracturing after closed acidization, acid etching fracture conductivity was up to 269 μm2.cm under 40 MPa closing pressure which increased 1.7 times compared to before closure acid. The corrosion morphology appears fine after acid-rock reaction and have obvious groove with depth of more than 0.5 ~ 4.5 mm, which could bear high closure pressure and improve long-term conductivity. Meanwhile, the conductivity is better than 5-stage common acid and 5-stage gelled acid, showing much more better liquid properties.