Are there any pre-treatment units in the KAI membrane brine process that are not fitted with anti-corrosion measures?
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This post was last edited by sunjl1981 on 2013-1-6 at 22:22. The iron ion level in saltwater is too high; some people suspect that the anti-corrosion coating in the pre-treatment units has come off, while others say that some factories don’t even use such anti-corrosion measures, yet the iron ion level remains within acceptable limits. Is this possible? # hcbbs
Corrosion protection is necessary, but implementing it during the preprocessing stage is difficult; the only method used is applying glass flake coating, and it’s hard to ensure the quality of the result. It’s probably better than doing nothing.
It should be done. The anti-corrosion coating we use is ethylene ester epoxy glass flake; it can be applied by brushing or by using putty, with the latter giving better results
There are also those that use epoxy coatings, which are applied by brushing; Shanghai Chlor-Alkali uses them and the results are good. I believe that anti-corrosion treatment must be carried out in any case – it is not only a requirement for process control but also necessary to prevent equipment damage caused by corrosion.
It seems that no one has dared to refrain from doing it, given the cost of the equipment and the difficulty of maintaining it. However, the pipes that carry our brine under pressure to the floating tank are all thick-walled seamless tubes, and no excess levels of iron ions have been detected during use.
It is said that there are indeed manufacturers that do not use any anti-corrosion measures, and the pipes are made of carbon steel; however, the iron content in them is not above the allowed limits. It’s simply unbelievable.
Corrosion protection should be carried out, as it is beneficial for the equipment. To determine whether it is the preprocessor that causes the excessive iron content, analyses should be conducted before and after preprocessing in order to find the real cause.
Anticorrosion measures should be taken; I think using rubber lining or glass flake coating would be more effective
The excessive iron content in saltwater is caused by the introduction of such elements from raw materials and auxiliary substances, or by corrosion of pipeline equipment; it is recommended to apply anti-corrosion treatment to pipeline equipment.
Was the pre-treater still treated with corrosion inhibitors when ferric trichloride was used as a sedimentation aid?
If the anti-corrosion quality is not up to standard, peeling is possible. We use flake resin for coating, but leaks have occurred at the welds; however, no problems were found after performing repair welding. The high iron content is likely due to the use of raw salt or to the amount of ferric chloride added. It’s unlikely that equipment corrosion is the cause of the high iron content; this is just my personal opinion. I welcome any feedback from everyone