A question about steam heating
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When heating with saturated steam at around 0.4 MPA, the liquid causes significant corrosion; can I use a PTFE heat exchanger? The quality of that brand is good; it can be used for a long time under such pressure. Those who have used it, please share their experiences. Also, is it possible to pass such steam into a liquid? By heating it to around 110 degrees, can this pressurized steam be passed through directly? It is said that the noise is very loud; is there any way to deal with it?
It has not been used yet, but PTFE is corrosion-resistant and can handle this temperature without issue. Is steam introduced directly into the liquid? This is a mixture; it’s no longer a heat exchanger. Make a large tank lined with PTFE
What is a liquid? Could it be aqua regia? Is it possible to work with stainless steel 316L?
I am a heat exchanger designer. Could you tell me about the medium and operating conditions required?
For corrosive liquids, if steam is directed directly into them, isn’t that the same as adding water? Usually, the corrosion will be even worse. PTFE provides corrosion resistance, but its thermal conductivity is an issue.
Steam is rarely used directly to raise the temperature of the material; it is generally employed for heating water, and there is considerable experience in this area. By providing more holes in the injection pipes, water hammer can be effectively prevented. However, two things need to be taken into account: first, the temperature difference should not be too large, and second, the steam pressure must be higher than that of the material.
Reply to 6# hanwentao: A 40% nitric acid solution, heated to boiling. Some people say that zirconium tubes are good at withstanding nitric acid, and internal heating can be used, but the space inside is quite limited. Approximately 0.8 M2 of heat exchange area is required, and the tubes need to be thin.
Based on experience, 316L can be used at temperatures around the boiling point for 40% dilute nitric acid; at concentrations higher than 70%, it is suitable at room temperature. However, corrosion occurs more rapidly at temperatures above 50°C, especially in acids with a concentration of over 90%. Generally, austenitic stainless steels are only used in concentrated nitric acid at room temperature. You can give it a try, but I can’t guarantee it for too long.