The authoritative public forum
  for Metal Finishing since 1989
-----

Reuse of material

I have a large quantity of spent sulfuric acid solution(3% acid 97% water)with a pH of 1. I was curious as to the uses of such a material. Can it be used to neutralize pH levels at say a wastewater treatment facility? If there are any uses, how would I find interested parties.

Chris Fugate
- Nicholasville, Kentucky, USA
2003

That solution is a little weak for most neutralization uses.

10-15 years ago there used to be a very large number of locally funded "waste exchanges" and you may try that term in a search engine as there are still a few left here and there.

But newer enforcement actions have convinced most shops that I am familiar with that this kind of conservation isn't worth the regulatory hassle. I don't know of a single shop that is interested in this kind of thing anymore now that we are in an age when regulatory agents barge in with a "What's this!?!" attitude. It's bad enough to have to explain your own processes without having to justify a tankful of someone else's waste. Vent mode off :-)

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2003

Dear sir,

Why don't we use that weak acid waste to produce gypsum, simply add it with calcium carbonate? I hope this tailed gypsum will be marketable for any cement plant in your country, or are there any environmental regulation that forbid us to sell this kind material?

Thanks,

Tommy Nugroho
- Indonesia
2003

You might try talking to some farmers in your area. Some may want to use it on their fields for the sulphates.

Kris Heim
- Walkerton, Indiana
2003

---

2003

I would NOT recommend letting farmers spray a pH 1 solution that came from YOUR facility on their fields. If it is not of use to you any longer, it is waste. Furthermore, if it has a pH of 1, it is D002 HAZARDOUS WASTE. Ever heard of Times Beach? (For effect guys, different materials...)

Ted has the right idea of checking out the material exchanges. Unfortunately, he is also correct that the reuse regs can be a hassle. Re-Use of untreated waste as a substitute for virgin/commercial material completely exempts you from the solid waste rules. If it's not "solid waste" it can't be "hazardous waste."

Technically, you first should find a user of your material. Then, ensure that NO Treatment is being done to the material either by you or them. Ensure they have the equipment and process to use it as they have indicated. Most importantly, document all of this. Send this information into your state's environmental agency for a "Regulatory Determination." The good news is that, if you follow these steps and are granted an exclusion, this stream can be removed from your list of hazardous wastes generated. YEAH! This is 40CFR 261.2(e)(1)(i)&(ii).

Traci Harmon
- Joplin, Missouri, USA