加压釜的腐蚀与防护

Corrosion and protection of autoclave

加压釜是镍钴湿法冶金加压浸出的关键设备,研究其抗腐蚀性能和安全防护对稳定生产极其重要。本文对某镍冶炼厂3^#加压釜进行了腐蚀分析,发现腐蚀部位为砖缝胶泥、陶砖和金属件。胶泥腐蚀是从加压釜的气相部位开始的,在应力集中、高温高压富氧条件下,胶泥易老化,继而疏松脱落;陶砖因胶泥的腐蚀而开始出现腐蚀;金属件腐蚀的主要原因是钛板薄、强度低、易变形,不能有效隔离矿浆对隔墙砖板的搅拌冲刷腐蚀。通过停釜检查,该厂从金属部件、砖板衬里等的用料、结构、施工方面进行了优化改进,并采取了严格质量施工管控,取得了较好的防腐效果,保障了加压釜的正常安全运行。

A autoclave is a key equipment for pressure leaching of nickel-cobalt hydrometallurgy,and its corrosion resistance and safety protection are extremely important for stable production.In this paper,corrosion analysis was conducted on the 3^# autoclave of a nickel smelter,and it was found that the corroded parts were brick cement,ceramic tiles and metal parts.The cement corrosion starts from the gas phase of the autoclave.Under the conditions of stress concentration and high temperature,high pressure and oxygen enrichment,the cement easily ages,and then looses.The ceramic tiles began to corrode due to the corrosion of the cement.The main reason for the corrosion of metal parts was that the titanium plate was thin,low in strength,and easy to change.It cannot effectively isolate the erosion and corrosion of the slurry on the brick wall of the partition wall.Through the shutdown inspection,the plant has optimized and improved the materials,structure,and construction of metal parts,brick lining,etc.,and adopted strict quality construction management and control,which has achieved good anti-corrosion effects and ensured the autoclave normal and safe operation.