Urgent help – Selection of hydrochloric acid delivery pipeline
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Urgent help – I am transporting 36% hydrochloric acid, what type of pipeline should I use? Is PVC-U suitable? Please ask the teachers for help. Thank you so much! ! ! (Please ask the teachers to provide a detailed explanation.)
From the perspective of corrosion resistance, PVC, PP, PE-lined steel or PTFE-lined steel, as well as fiberglass-reinforced plastic, are all suitable options. For long-distance, large-diameter pipelines, fiberglass-reinforced plastic is considered the most reliable choice; for shorter distances with lower pressures, PVC and PPH can be used. However, to ensure safety, it is recommended to coat the joints with fiberglass-reinforced plastic to strengthen them and prevent leaks of concentrated hydrochloric acid from causing harm.
Our company has used PE-lined steel, PVC reinforced with fiberglass, and fiberglass pipes, but the performance of these materials was not very good. Firstly, steel-lined PE pipes are prone to bulging, which can cause blockages in the pipes. FRP-reinforced PVC and FRP pipes are susceptible to leakage. What we use now are reinforced polypropylene pipes, which are made through integral molding; they perform well and offer a good cost-performance ratio.
I’m not sure about the conditions of hydrochloric acid on the first floor; if the temperature is below 70 degrees and the pressure is below 1.0–2.0 MPa, it is recommended to use PE pipes with a steel framework. Usually, a lifespan of 5-10 years is no problem.
Our factory uses fiberglass reinforced plastic! !
Thank you, teachers, for your guidance! The operating conditions are: temperature not exceeding 55 degrees, hydrochloric acid concentration of 36%, with above-ground pipelines connected to the equipment.
Additional note: Some people say PVC or PVC-U (UPVC), while others say FRPP can be used as well. I’m really stuck; I hope the teachers can help me solve this. Thank you so much for your participation and guidance.
Reply to 7# gfc_china: It is recommended to use steel-reinforced plastic composite pipes, which are pressure-resistant and corrosion-proof, easy to install, and offer better performance than PVC pipes.
If you want a low cost, use PVC or fiberglass; however, they don’t last long. For durability, use steel-lined PTFE or steel-lined PE. But the price is high.
For the medium conditions you mentioned, using steel-lined PP offers the best results in terms of performance, as well as safety and environmental sustainability
Both fiberglass-reinforced plastic and steel-lined PTFE pipes are available