I’d like to (must) make sure my plate chiller is clean. Too many “flavor crystals” are still coming out after long recircs with hot Oxyclean (forward and back-washing). I’d like to try sodium hydroxide (lye/caustic soda).
I have a March 809HS-PL pump. Silicone and thermoplastic hoses with SS camlocks. The only soft metal in the circuit is the copper brazing in the heat exchanger.
Q1: Will I trash any of my equipment recirculating hot caustic soda through?
Q2: What percent solution will give me adequate cleaning with the least corrosive effects?
And yes, I will be super safety-man and use all appropriate ppe (gloves, goggles, splash shield, boots, old clothes, etc.)
No, I have been using it for about 2 years (about 40 batches) without any problems.
2.5% w/w
Would not do it any other way.
I mix mine with a product called chlorinated pipeline cleaner which is used in the dairy farm industry. It has surfactants and chelating agents to help remove stuck on material and aids with rinsing.
Forgive the silly question, but did you try PBW? Is Oxyclean similar? I’ve also wondered about cleaning with NaOH because I used to make soap for a living and still have a few pounds of NaOH (and KOH) around with no real use for it.
One caution - always always always add the NaOH to water and not the other way around. Adding water to a container of NaOH can cause it to volcano up and make for a pretty awful day. Also, if it is possible, mix this stuff outside as it gives off some very wicked fumes initially. Keep in mind that it will also get rather hot (up to about 180 degrees, depending on how much NaOH you’re using). No offense meant if you already know this, but for the sake of other people reading this in the future, I would hate for someone to get hurt.
Also remember you will want to get the caustic soda around 160-170 degrees to make it really effective. Add sodium hydroxide to cool water then heat up. Always add lye to water, never add water to lye as it will have a violent reaction.