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Relative 'corrosivity' of pH adjusting acids in aqueous waste streams on black iron grease trap components

 

My job is to reduce high strength effluents from industrial waste streams, example - food processing plants, petrochemical plants, fabrication, pulp and paper plants, etc.

Food processing plant waste streams as well as others must adjust pH before releasing to municipal collection systems.

Several food processors adjust pH done by using 'vinegar' which is readily available in-house and obviously an inexpensive source of material to lower pH.

This results in extensive corrosion of the grease trap/skimmer system for all metal parts (walls, gears, drive chains, etc.

Question? Would an alternate acid (SUCH AS PHOSPHORIC)be a better choice to adjust pH lower resulting in a less corrosive environment in the system ultimately resulting in a reduced recurring expensive maintenance schedule for the grease trap system.

I suppose my real question might be which common acids are less corrosive to aqueous food plant waste streams than vinegar [in bulk on eBay or Amazon].

Thanks,

Wayne A Fleming
- Dallas, Texas

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An advantage of vinegar is that, being a food, it is obviously safe.

An idea that may prove impractical, but would be fun to try in the lab, is to electrolyze the solution to raise the pH. I think you will find that the water will separate into H2 gas bubbles and 2OH-, raising the pH. As I say, it may be totally impractical, but give it a thought.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey