Materials resistant to chloride corrosion
Thread Content
Due to project requirements, materials resistant to chloride corrosion are being sought for use as tubes in shell-and-tube heat exchangers； The detailed conditions are as follows: temperature 10–60°C, pH=6.8 (sodium bicarbonate-type solution); chloride ion concentration 1100 mg/l. The solution contains no other corrosive ions, with only trace amounts of ferrous ions ； Upon checking relevant information, excluding the expensive Hastelloy, Monel, and titanium materials ； Can duplex stainless steel 2205 and nickel-copper alloy B10 handle these operating conditions? Are there any available corrosion data on this topic? I would appreciate guidance from those with more experience; I’m very grateful
I’ll start with one first; I hope the experts will be kind enough to offer their guidance
Let me throw out an idea first – I remember that ordinary carbon steel is used along with anodic materials for protection (I’m not exactly sure what kind of materials they are; you can look it up online):D
It is recommended to use titanium plates; titanium has a low density, so the overall performance is not very different from that of 2205.
What is the work pressure? If the pressure is not too high (around 10 kg/cm2), it is recommended to use a graphite heat exchanger to ensure no problems.
Thank you so much for your suggestion! I am mainly selecting materials for heat exchangers. Carbon steel has relatively poor heat transfer properties and corrosion resistance; could this lead to an increased required corrosion allowance and a larger area for the heat exchanger? Also, is the anode material protection you mentioned feasible for such operating conditions? What issues need attention
Won’t graphite heat exchangers be too prone to damage? I plan to use them as heat exchangers, with Freon flowing in the shell side – will graphite heat exchangers work for this purpose?
We actually considered using titanium as well, but it’s too expensive; my project is located in an oil field. What is the impact of this ratio on the material selection for heat exchangers? I would be extremely grateful for any further guidance you could provide
With the same wall thickness, the weight of titanium heat exchangers is nearly 40% less than that of 2205 materials; as a result, their overall prices are similar. Furthermore, if it is made into a plate heat exchanger, more material can be saved. You can provide the parameters so that the plate heat exchanger manufacturers and the shell-and-tube heat exchanger manufacturers can calculate separately and compare the costs of the two materials.
Hello: Our company has just manufactured a 5-meter long heat exchanger, with the inner surface of the steel tubes coated in PTFE; the tube sheets and baffle plates are made of 30mm thick PTFE plates, and the tube bundle is also made of PTFE.
Whether a graphite heat exchanger is prone to damage depends mainly on process parameters such as the medium, temperature, and pressure; if it is properly selected, it can be very durable.