Help: Which is more resistant to corrosion by ethylene glycol solution, copper or 304 stainless steel?
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Help: Which is more resistant to corrosion by ethylene glycol solution, copper or 304 stainless steel? We have installed several chilled water heat exchangers made of copper, and leaks have occurred on multiple occasions during operation. We want to replace them with those made of 304 material, but we’re not sure which one is more durable.
It is estimated that there are chloride ions in the water; be sure to measure it
Given your situation, using a graphite heat exchanger can completely resolve the corrosion issue. Moreover, graphite heat exchangers have a high overall heat transfer coefficient and a low cost (comparable to that of stainless steel).
The vibration is too severe; graphite heat exchangers are not suitable. Also, if the heat exchange area is 30-40 cubic meters, what size graphite heat exchanger should be used?
Graphite heat exchangers with a size of 30–40 square meters have a diameter of 700 mm and a height of over 2 meters.
You might be referring to a refrigeration unit. As for material selection, I’m not very familiar with it, but stainless steel should be avoided in the presence of chloride ions, while copper should be avoided in the presence of hydrogen sulfide. We have encountered corrosion problems with the chiller; the temperature is around minus 5°C, and the medium used is ethylene glycol along with circulating water. The tubes are made of copper, while the tube sheets are made of carbon steel. After one or two years of use, corrosion did occur; there were defects such as corrosion pits in the area of the tube sheets. We repaired them using polymer-ceramic-metal composites and provided protection with cerametal coatings. After 4 years of use, the condition is still excellent – the coatings remain intact with no signs of corrosion. You can take it as a reference.
I have a question: my heat exchange tubes are also made of copper, and the cooling medium is an ethylene glycol solution. However, in less than a week, the ethylene glycol coolant turned blue Do you experience this when using it?
Didn’t your ethylene glycol solution turn blue? The heat exchange tubes I used are also made of copper, and the cooling medium is an ethylene glycol solution; however, in less than a week, the ethylene glycol coolant turned blue Do you experience this when using it?
If it is ethylene glycol free from harmful impurities, using S30408 is no problem.
Our company previously used ethylene glycol solutions, and corrosion and leakage issues occurred as well. We later learned that ethylene glycol solutions tend to acidify when exposed to heat; this acidity can cause corrosion in metals such as carbon steel, stainless steel, and copper that come into contact with it. Therefore, we switched to Chaoyang Sunlight Chemical’s refrigerant medium, and after using it for 5 years, no signs of corrosion have been observed – its performance is indeed excellent.
OP, did you end up using stainless steel? Is it still corroding?