凝汽器铜管氨腐蚀分析及其无铜化改造

Analysis of the condenser ammonia corrosion and its non-copper modification

全面分析了凝汽器铜管氨腐蚀机理及其影响因素,并探讨一定的防护措施,指出采用双面强化传热不锈钢管是凝汽器无铜化改造的最佳选择.基于此,利用水平式单管传热与流阻特性通用试验装置,以水蒸汽、水为工质,对2种钢质双面强化传热管--螺旋槽管和新近研制出的内螺旋外棘齿管进行了冷凝换热特性和流体动力学特性试验研究.依据试验结果,对采用双面强化传热不锈钢管的凝汽器改造方案进行了经济效益分析.基础试验结果表明:螺旋槽管的总传热系数要比光滑管提高10%～17%,内螺旋外棘齿管的总传热系数好于螺旋槽管,是光滑管的1.22～1.28倍;经济分析表明:采用不锈钢螺旋槽管的改造方案比不锈钢光滑管具有更好的综合技术经济性能.

This paper analyzes comprehensively the mechanism of condenser copper pipe corrosion and the influencing fac-tors,and presents some prevention measurement and methods.The stainless steel tube with double side enhancement heat transfer is proved to be the best choice for condenser reconstruction in non-copper issue.Based on this,using a general steam condensation testing equipment only for horizontal single tube,with water vapor and water as working fluid,on two types of steel tube with double side enhancement heat transfer,namely,spirally fluted tube ratchet tube with internal spiral groove(RISG tube) which was developed recently,a set of experimental tests are performed to investigate the characteris-tics of heat transfer and hydromechanics.According to the experimental results,economic benefit analysis is carried out for condenser reconstruction scheme with 2side enhancement tube as heat transfer tube.The experimental results show that the overall heat transfer coefficient of spirally fluted tube is improved by 10% to 17%,and that the RISG tube is better than spirally fluted tube.Its enhance value is 1.22 to 1.28 compared with smooth tube.The economic benefit analysis results show that the scheme with 2 side enhancement tube as heat transfer tube has better integration technology economy perfor-mance than that with only stainless steel smooth tube as heat transfer tube.