Reasons for heat-induced corrosion during transformation
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Not long ago, during a visit to a sulfuric acid plant, the user discovered a leak in the heat pipes. Under normal circumstances, the heat exchanger is not affected by entrained acid. However, the user found that the bypass valve of the upstream cold exchanger was open; it is possible that secondary acid entrained from the upstream fiber demister reached the heat exchanger through the cold exchanger bypass, thereby causing corrosion and leakage in the heat exchanger. I learned that there was a period when the upstream fiber demister had perforations, and I promptly agreed with the analysis provided by the factory technicians. Of course, if the cold exchange efficiency is low and the bypass valve remains closed, in such a case the secondary acid entrainment from the upstream fiber demister should not affect the heat exchange.
The acid removal efficiency of the defoamer can’t be 100%, right?
The key issue is acid carryover; often, the acid mist levels measured downstream of the demister are within acceptable limits, but the pipes and equipment downstream contain a significant amount of acid.
How many times has it been changed? 4-way or 5-way replacement – it’s mainly due to corrosion by condensing acid
In other words, what was tested did not reflect the actual situation, right?
It’s a problem with the fiber mist eliminator; the Brink mist eliminator comes equipped with a layer to prevent secondary entrainment
Is it sulfur used to produce acid? There is internal leakage in the hot exchange; is there any internal leakage in the cold exchange?