Okay, so I had this project where I needed to pump hydrochloric acid, and let me tell you, finding the right pump material was a headache. I mean, this stuff is nasty, it’ll eat through metal like it’s nobody’s business. So, I started digging.
My Research and Trials
First, I checked some online forums and some manufacturer websites. I quickly learned that regular stainless steel? Forget about it. Hydrochloric acid would chew that up in no time. I needed something way tougher.
- Option 1: Plastics. I looked into things like PVC and CPVC. They’re okay for low concentrations, but I was dealing with some pretty strong stuff. So, those were out.
- Option 2: Fancy Plastics. Then I discovered materials like PVDF (Kynar) and PTFE (Teflon). Now we’re talking! These are known for being super resistant to chemicals. I felt like I was getting somewhere.
- Option 3: Even Fancier Stuff. I also stumbled upon Hastelloy and other high-nickel alloys. These are the big guns, the real heavy-duty materials. But, they also come with a hefty price tag.
I decided to do some small-scale tests. I got my hands on some samples of PVDF and a small piece of Hastelloy. I made up a batch of the hydrochloric acid I’d be using and submerged the material samples.
I checked them regularly, looking for any signs of corrosion, swelling, or any change, really. I observed the PVDF for several days. No problems there!
My Solution and Testing Process
Then I tested Hastelloy. I used it for weeks, and no problems. I observed the samples for days, and they both held up great! The PVDF was definitely the more budget-friendly option, and since it passed my tests with flying colors, that’s what I ultimately went with.
For the actual pump, I made sure all the wetted parts – the parts that actually touch the acid – were made of PVDF. The pump casing, impeller, everything. No shortcuts!
It’s been running for months now, and no leaks, no corrosion, nothing. I’m pretty happy with how it all turned out. Picking the right material was the key, and doing those little tests gave me the confidence I needed.