目的 考察陕北某天然气处理厂回注系统的腐蚀情况，保证系统安全生产。方法 在水质分析的基础上，用现场材质20#钢和计划替换钢材L316研究回注水处理系统的腐蚀现状，随后选择腐蚀最严重环节的水样为介质，采用静态失重法考察温度、pH值、溶解氧、细菌对20#钢材腐蚀速率的影响。结果 陕北某气田气井产出水的总矿化度较高（30 000 mg/L左右），其中Ca2+、Mg2+等金属阳离子的含量较高，腐蚀速率随水介质中溶解氧含量的增加均呈上升趋势，在80 ℃、溶解氧为5.07 mg/L时，腐蚀速率最大，达到0.4001 mm/a。随着细菌含量的增大，腐蚀速率上升，腐蚀速率由0.1065 mm/a（TGB 60个/mL，SRB 6个/mL）增加到0.2155 mm/a（TGB 6×104个/mL，SRB 6×103个/mL）。pH值为5.9时，腐蚀速率为0.3039 mm/a；当pH值为8.5时，腐蚀速率降至0.0710 mm/a。结论 通过做好回注水处理系统pH调节、杀菌和隔氧等工作，可以减轻系统的腐蚀。

The work aims to investigate corrosion situation of reinjection water treatment system in gas processing plant in northern Shaanxi, and guarantee safe production of the system. The 20# and L316 steel on the site were used to study the corrosion situation of the system on the basis of water quality analysis. Water sample in the cycle subject to worst corrosion was selected as the medium. Effects of temperature, pH, dissolved oxygen and bacteria on corrosion rate of 20# steel were investigated in static weight-loss method. Total salinity of water produced from a gas field in northern Shaanxi was high (about 30 000 mg/L), so was content of metal cations including Ca2+ and Mg2+. The corrosion rate increased as dissolved oxygen content increased, and the corrosion rate was up to 0.4001 mm/a at 80 ℃ provided with 5.07 mg/L DO. The corrosion rate increased from 0.1065 mm/a to 0.2155 mm/a while the TGB increased from 60 cfu/mL to 6×104 cfu/mL, and SRB from 6 cfu/mL to 6×103 cfu/mL as bacteria content and corrosion rate increased. The corrosion rate decreased from 0.3039 mm/a to 0.0710 mm/a as pH value increased from 5.9 to 8.50. Corrosion of the system can be reduced by taking appropriate anticorrosion measurements including pH adjustment, sterilization and oxygen isolation.