Selection and application of the inner lining in the first-stage power wave transition section shell
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This post was last edited by in the blink of an eye on 2017-5-13 at 18:57. Ever since Mengmoke Company introduced the power wave washing technology to the sulfuric acid industry in China, the primary power wave transition section has always been a vulnerable component; few users order spare parts for this component from Mengmoke Company. Over the years, the domestic sulfuric acid industry has made many improvements to the transition sections for primary dynamic waves, mainly in terms of the lining inside the shell. There are roughly the following types: 1. Lead plating; the main problem is that when exposed to high temperatures over a short period of time, the lead-plated lining softens or even melts, leading to the detachment of the lining bricks. 2. The lining is made of Hastelloy G30, but corrosion of the G30 lining still occurs. 3. PTFE lining: Due to the substandard quality of PTFE linings available in China, in practice it has happened that the PTFE lining on the flange at the transition section collapses, causing blockages in the overflow weir. The originally imported version uses a tight-fitting PTFE lining. Last year, I went to a customer’s site to inspect the original imported transition section; although some of the lining tiles had fallen off, the PTFE lining on the flange surface at the transition point did not collapse. My personal opinion is that if the PTFE lining meets the requirements, it remains the best choice.
I wonder if the original poster and others have considered using metals such as tantalum, niobium, and zirconium. I manufacture heat exchangers and containers with corrosion-resistant linings made from these high-end corrosion-resistant metals here.
The lining issue in the transition section is indeed worth everyone’s attention and discussion
The dry-wet interface at the inlet of the power wave is a region where corrosion, wear, and detachment occur severely. The high-temperature dilute acid corrosion is even more intense in the temperature range where the flue gas cools below its dew point temperature. In various projects undertaken by our company in the past, lining materials such as graphite and Hastelloy have all suffered from corrosion and wear. Currently, some manufacturers use non-metallic materials such as high-temperature resistant fiberglass and lined corrosion-resistant materials, which also yield certain results; there is hope that metallic materials such as tantalum, niobium, and zirconium will prove effective as well.
As long as the flue gas temperature does not exceed 350°C, there should be no major issues with a lead-antimony alloy lining; the key lies in the treatment technique of the inner surface