净化厂换热器腐蚀影响因素及原因分析  

Analysis of influencing factors and causes of heat exchanger corrosion in purification plant

作　　者：黄刚华 范锐[4] 曹军[1,2,3] 黄丽华 Huang Ganghua;Fan Rui;Cao Jun;Huang Lihua(Research Institute of Natural Gas Technology,PetroChina Southwest Oil&Gasfield Company,Chengdu,Sichuan,China;National Energy R&D Center of High Sulfur Gas Exploitation,Chengdu,Sichuan,China;High Sulfur Gas Exploitation Pilot Test Center,CNPC,Chengdu,Sichuan,China;PetroChina Southwest Oil&Gasfield Company,Chengdu,Sichuan,China)

机构地区：[1]中国石油西南油气田公司天然气研究院 [2]国家能源高含硫气藏开采研发中心 [3]中国石油天然气集团公司高含硫气藏开采先导试验基地 [4]中国石油西南油气田公司

出　　处：《石油与天然气化工》2022年第1期98-103,共6页Chemical engineering of oil & gas

摘　　要：目的分析川渝某净化厂换热器的腐蚀原因及影响因素,探讨解决措施。方法通过微观分析换热管束泄漏的原因,采用旋转挂片法室内考察了换热器内循环水中的Ca^(2+)、HCO_(3)^(-)、Cl-、SO_(2)-4对腐蚀的影响。结果换热管束泄漏是由腐蚀导致的,腐蚀从管束的内表面开始,逐渐形成腐蚀孔,最后导致换热管出现腐蚀泄漏。循环水中Ca^(2+)、HCO_(3)^(-)对水质的腐蚀性影响较大,当循环水中的ρ(Ca^(2+))低至44 mg/L时,系统中碳钢的腐蚀速率高达1.05 mm/a。结论为了防止管束发生腐蚀失效,需要加强水质控制,提高系统的Ca^(2+)含量、碱度,或者更换耐蚀性更高的材质。Objective The cause for corrosion in heat exchangers at a single natural gas purification plant located in Sichuan-Chongqing area was studied as well as the influencing factors so as to reach the technical solutions.Methods Microscopic analysis was conducted to study the cause for leakage in the tube bundles while the influences of Ca^(2+),alkalinity,Cl^(-) and SO_(4)^(2-) in the circulating water on corrosion rate were investigated by rotary hanging plate method.Results The leakage in the heat exchange tube bundle was caused by corrosion.During the process,corrosion occurred first at the inner surface of the tube bundle,which then gradually grew to form corrosion holes and finally led to the leakage.Ca^(2+)and alkalinity were revealed to be closely related with the corrosivity of the recirculating water:when the Ca^(2+) concentration was as low as 44 mg/L,the corrosion rate of the carbon steel could reach as high as 1.05 mm/a.Conclusions In order to prevent the corrosion failure of tube bundle,it is necessary to enhance the water quality control by increasing the Ca^(2+) concentration and alkalinity in the system or using material with higher corrosion resistance.

关 键 词：换热器 循环水 腐蚀 腐蚀防护 

分 类 号：TE986[石油与天然气工程—石油机械设备]