影响脱硫溶剂UDS与MDEA腐蚀性的因素考察及比较

Investigation and Comparison of Influencing Factors of the Corrosion Properties of UDS and MDEA Desulphurization Solvent

关键词:  高酸性天然气  UDS溶剂  腐蚀  无机氯  有机氯

Key words:  high-sour natural gas  UDS solvent  corrosion  inorganic chloride  organic chloride

摘要:

为了有效改善天然气净化溶剂的腐蚀性,通过挂片失重法对脱硫溶剂UDS与MDEA的腐蚀性进行了比较研究,考察了温度和溶剂氯含量对两种溶剂腐蚀性的影响。实验表明,随着温度的升高,两种溶剂的腐蚀性均随之增强。在120℃以下,UDS和MDEA溶剂对不锈钢挂片的腐蚀速率增加缓慢;在120℃～150℃之间,两种溶剂对不锈钢挂片的腐蚀速率显著增大;在30℃～120℃范围内,两种溶剂对20#碳钢挂片的腐蚀速率逐渐增加;UDS富液的腐蚀速率是贫液的96倍左右。随着溶液中氯含量的增大,UDS和MDEA溶剂的腐蚀速率均增大,且无机氯对溶剂腐蚀的影响要强于有机氯;UDS溶剂对20#碳钢挂片的腐蚀情况比MDEA溶剂的弱。

Abstract:

In order to effectively reduce the corrosion of natural gas purification solvents,the corrosion of UDS and MDEA solvents are investigated and compared.The corrosion rates of these two solvents under various temperatures and chloride contents are determined using the stainless steel coupon weight loss method.The results indicate that the corrosion of both the UDS and MDEA solvents increases as the temperature increases,and the corrosion of the two solvents to the stainless steel coupon increases slowly below 120℃,the corrosion of the two solvents to 20# carbon steel increases between 30℃～120℃.As UDS solvent,the corrosion rate of rich solution is about 96 times larger than that of lean solution.Furthermore,the corrosion rate of both UDS and MDEA increases as the contents of chloride increase.With the increase of the contents of inorganic chloride,the corrosion influences on UDS and MDEA solvents are obviously larger compared to organic chloride.The corrosion of UDS to 20# carbon steel is weaker than that of MDEA solvent.