Chloride ion corrosion problem
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We plan to treat the wastewater by using a mist evaporation unit to accelerate the evaporation of water. However, due to the high chloride ion concentration of 120,000 mg/L, the manufacturers of such evaporation units recommend using 316L material along with a phosphated coating to prevent corrosion caused by chloride ions. Our suggestion is to use PPH or PE for the surface coating. We would like to know whether 316L material combined with a PPH surface coating can resist such high levels of chloride ion corrosion Here, the pH value of the wastewater ranges from 7 to 10, and the treatment is carried out at room temperature. I would appreciate some advice from experts in this field. Thank you.
What materials are resistant to such high levels of chloride corrosion? Are Monel alloy and Inconel 625 alloy options available? It’s just that the price of these metals is too high. What are some low-cost materials resistant to chloride corrosion?
Spraying is theoretically possible, but it’s difficult to ensure proper implementation; it is recommended to use a graphite evaporator
This chloride concentration has reached 120 g/l; together with the cations, the salt content is too high. Evaporation using sunlight would be the best solution. For this type of material, it is best not to use stainless steel, as the spraying effect is not very reliable.
316L definitely won’t hold up. Using nickel alloys is costly. Spraying is quite difficult
Impervious graphite material is currently the most cost-effective option for resisting chloride corrosion, and it can be used to manufacture various chemical processing equipment such as heat exchangers, reactors, tower devices, and evaporation concentration units. Impermeable graphite materials can be used for extended periods at the boiling point of hydrochloric acid at any concentration without suffering from corrosion.
On the one hand, manufacturers of atomization evaporators have not produced ones made of titanium or nickel alloys; on the other hand, the cost is too high. We have informed the manufacturers of the atomization evaporators about the situation with chloride ions, and they said that using 316L material with powder coating can resist corrosion caused by such high concentrations of chloride ions; however, we’re not sure if this is true or not.
On the one hand, manufacturers of atomization evaporators have not produced ones made of titanium or nickel alloys; on the other hand, the cost is too high. We have informed the manufacturers of the atomization evaporators about the situation with chloride ions, and they said that using 316L material with powder coating can resist corrosion caused by such high concentrations of chloride ions; however, we’re not sure if this is true or not.
On the one hand, manufacturers of atomization evaporators have not produced ones made of titanium or nickel alloys; on the other hand, the cost is too high. We have informed the manufacturers of the atomization evaporators about the situation with chloride ions, and they said that using 316L material with powder coating can resist corrosion caused by such high concentrations of chloride ions; however, we’re not sure if this is true or not.
Using nickel alloys is too costly, and vaporization evaporator manufacturers have also not used this material before
Is an evaporator made of graphite a heat exchanger that uses steam to evaporate wastewater?