胶凝酸腐蚀实验中添加剂的配伍性研究

A Study on Compatibility of Additives in Gelled Acid Corrosion Experiments

根据有关行业标准,胶凝酸用缓蚀剂的性能一般在只加入缓蚀剂的酸液中进行测试。本研究工作表明这种作法在温度小于90℃时是可靠的,在更高温度下则不可行。在只加入高温缓蚀剂WD-11+缓蚀增效剂WZD-3的20%盐酸(单剂缓蚀酸)和加入了胶凝剂WD-13B+转相剂WD-26、助排剂WD-12、黏土稳定剂WD-5及铁离子稳定剂WD-8的单剂缓蚀酸(配方胶凝酸)中,140℃时N80钢试片的腐蚀速率分别为56.90和1622.26 g/m2.h。单剂测试结果表明,助排剂与高温缓蚀剂在酸液中不配伍,腐蚀速率高达332.56 g/L,胶凝剂+转向剂、黏土稳定剂、铁离子稳定剂在酸液中与高温缓蚀剂配伍性好,腐蚀速率略有降低。在不加助排剂的配方胶凝酸中,腐蚀速率仅为52.75 g/m2.h。该助排剂为阳离子型和氟碳类表面活性剂的复配物。从添加剂的作用机理讨论了以上实验结果。

According to a present Trade Standard,SY/T 5405-96 ,the performance of a corrosion inhibitor for gelled acids is assessed in plain acid with this chemical added as the sole additive. This work showed that this procedure was practicable only at temperatures 〈 90℃ and became undesimble at higher temperatures. In 20% hydrochlorie acid treated with 2. 8% high temperature corrosion inhibitor WD-11 ＋ 1.0% inhibition promotor WZD-3,shorfly the inhibited acid,and in the inhibited acid with gelling agent WD-13B ＋ phase converter WD-26,flowback aid WD-12, clay stabillzer WD-5, and ferreferdc ion stabilizer WD-8 added, shortly the formulated gelled acid, the corrosion rate of N80 steel specimens at 140℃ was of 56. 90 and 1622. 26 g/m^2 · h,respectively. The resuhs of single additive corrosion tests indicated that the flowback aid used was imcompatible with the corrosion inhibition chemicals and raised the corrosion rate in the inhibited acid significantly to 332. 56 g/m^2·h;the gelling agent ＋ phase converter,the Fe and the clay stabilizers used were well compatible with the corrosion inhibition chemicals and caused a slight decrease in corrosion rate. For the formulated gelled acid with the flowback aid excluded,the corrosion rate is as low as 52. 75 g/m^2·h. The flowback aid WD-12 is a combination of cationic and fluocarhon surfactants. The experimental results were discussed and explained in terms of functions of the acid additives.