输油站场缓蚀剂阻垢剂开发与性能评价

输油站场缓蚀剂/阻垢剂开发与性能评价

摘要

在石油开采、运输、存储、炼化过程中，需要用到大量的化工装置，在这些装置的使用过程中往往会遇到严重的腐蚀结垢问题。其中，原油站场作为原油输送的集散地，其管道内介质复杂多变，腐蚀和结垢问题往往更加严重，投加缓蚀剂是一种高效抑制金属腐蚀的手段，而投加阻垢剂是一种常用的抑制管道结垢的手段。研发输油站场用缓蚀剂和阻垢剂，有利于保证输油站场正常运行，预防生产事故。因此，本文在实验室合成了三种咪唑啉类输油站场用缓蚀剂和四种常用的阻垢剂，采用失重法和电化学方法研究了缓蚀剂的缓蚀效率，采用静态结垢实验分析了原油站场阻垢规律，并评价了四种阻垢剂的阻垢率，得到了以下结论：

通过对三处在役输油站场进行腐蚀结垢现场调研，发现在役输油站场存在严重的腐蚀结垢问题，其中管道的底部、埋地管道、法兰连接处、管道弯头处、原油储罐底部容易发生严重的腐蚀问题，管道死油段、沉积水存在处容易发生结垢问题；实验室合成了三种咪唑啉类输油站场用缓蚀剂，理化性能测试全部合格，电化学实验和失重法研究表明咪唑林季铵盐缓蚀剂的自腐蚀电流最小，腐蚀速率最慢，缓蚀效果最显著；通过静态结垢实验研究了pH、表面活性剂、温度、钙离子浓度对结垢的影响规律，并评价了四种阻垢剂的阻垢率，研究表明，溶液结垢率随 pH 值的增大而增大，随表面活性剂增加而减小，随温度增加而增大，随钙离子浓度的增大而增大；HEDP 具有最佳的阻垢性能，但其阻垢率同样受温度、Ca2+浓度以及 NaCO3浓度影响，温度在超过 70℃后，阻垢效率急剧下降，Ca2+浓度越大，缓蚀剂缓释效率越低，NaCO3浓度越大，阻垢效率越低。通过本文研究确定了一种最优的输油站场用缓蚀剂和阻垢剂，有利于完善输油站场腐蚀结垢防护体系。

关键词：输油站场；缓蚀剂；阻垢剂；失重法；电化学法；静态结垢实验

Development and Performance Evaluation of Corrosion Inhibitors and Scale Inhibitors in Oil Stations

Abstract

In the process of oil extraction, transportation, storage, and refining, a large number of chemical plants are required, and serious corrosion and scaling problems are often encountered during the use of these facilities.Therefore, in this paper, three kinds of imidazoline oil field corrosion inhibitors and four kinds of commonly used scale inhibitors were synthesized in the laboratory. The corrosion inhibition efficiency of corrosion inhibitors was studied by using weight loss method and electrochemical method. The scale experiment analyzed the scale inhibition rules of crude oil yards and evaluated the scale inhibition rates of the four scale inhibitors. The following conclusions were obtained:

Through field investigations of corrosion and scaling at three oil stations in service, it was found that serious corrosion and scaling problems exist at the oil station in service.Three kinds of imidazoline-based corrosion inhibitors were synthesized in the laboratory, and all physical and chemical performance tests were qualified.Imidazolium quaternary ammonium salt corrosion inhibitor has the most significant corrosion inhibition effect.In addition, the fouling rate of the solution increases with the increase of pH value, decreases with the increase of surfactant, increases with the increase of temperature, and increases with the increase of calcium ion concentration; HEDP has the best scale inhibition Performance, but its scale inhibition rate is also affected by temperature, Ca2+ concentration, and NaCO3 concentration.Through the study of this paper, an optimal corrosion inhibitor and scale inhibitor for the oil station is determined, which will help improve the corrosion and scaling protection system at the oil delivery station.

Key words: oil station; corrosion inhibitor; scale inhibitor; weight loss method; electrochemical method; static scale test