一种新型高效油气井酸化缓蚀剂的研制

A NOVEL HIGHLY-EFFICIENT ACIDIZING CORROSION INHIBITOR USED FOR OIL AND GAS WELLS

曼尼希碱是一类性能优良的缓蚀剂，并在油气井酸化作业中大量应用。为此介绍了一种新型曼尼希碱：在伯胺、甲醛、苯乙酮参与的曼尼希反应中加入丙酮，通过控制反应条件使得伯胺分子中氨基上的两个氢原子分别与苯乙酮、丙酮及甲醛发生曼尼希反应，得到该曼尼希碱，可以用作油气井酸化缓蚀剂的主剂。将该曼尼希碱与丙炔醇及有机增效剂复配后得到国内未见报道的高效油气井酸化缓蚀剂。以静态腐蚀速率为试验评价指标，用正交试验法对主剂的合成工艺条件进行优化，试验条件下获得的最佳合成工艺条件应为：总反应时间14h，反应原料胺醛酮的配比为l：2：4（物质的量比），pH值在2～3之间。同时对主剂与增效剂之间的协同作用进行了初步的探讨。静态腐蚀试验结果表明，复配后的产品具有优良的缓蚀性能。在90℃、20％的盐酸中加入1％的缓蚀剂，N-80钢的腐蚀速率可以降到0．96g／（m^2·h）。

Mannich base is a corrosion inhibitor with superior property and is applied widely in well acidizing treatments. For this reason, a kind of new Mannich base is introduced in this paper. In the Mannich reaction process, which is involved with the presence of primary amine, formaldehyde and acetophenone, acetone has been added. By controlling reaction conditions, two hydrogen atoms in amino of the primary amine molecule take the Mannich reaction with acetophenone, acetone and formaldehyde respectively and thus this new kind Mannich base can be obtained. And this Mannich base can be employed as the main agent of well acidizing corrosion inhibitor. Combining this Mannich base with propargyl alcohol and organic synergist can acquire highly efficient well acidizing corrosion inhibitor, which has not been reported in China so far. Taking the static corrosion rate as evaluation index, the synthetic technological conditions influencing main agent can be optimized by using the orthogonal test method. It is found out that under the experimental conditions, the best synthetic technological condition should be as followings: the total reaction time is 14 hours, the ratio (molar ratio) of reaction materials is 1∶2∶4 for amine, aldehyde and ketone, and the pH value is ranged from 2 to 3. At the same time, the paper has made the preliminary investigation of synergetic effect between main agent and synergist. The results of static corrosion test show that the compound agent has a fine inhibition performance. By adding 1% of the inhibitor to the solution with 20% hydrochloric acid at 90 degrees Celsius, the corrosion rate of N80 steel can be reduced to 0.96 g/(m2·h)