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pH control-neutralization calculation

pH control-neutralization calculation

pH control-neutralization calculation

(OP)
Hi everybody!
I am looking for an answer on how to determine the amount of chemical (HCl, NaOH) needed for bringing the pH in the 6.5-9.5 value? So, to simplify the question, here is the example:
I have a wastewater with a pH=11 (30 m3 batch). How much HCl (30%) do I need to add to the wastewater in order to bring the pH to 9.5?

Thank you for your answers!

RE: pH control-neutralization calculation

You need a chemical analysis that shows the alkalinity.

RE: pH control-neutralization calculation

(OP)
I don't have the analysis. There is nothing to be analysed yet, because the factory is not yet built. Are there some guidelines that can help with the dimensioning of the equipment?

RE: pH control-neutralization calculation

What type of facility? Do you have a raw water analysis?

RE: pH control-neutralization calculation

Do you know what volume of water you are going to have to treat?

Regards
Ashtree
"Any water can be made potable if you filter it through enough money"

RE: pH control-neutralization calculation

There are textbooks with tables that you can use to determine how much chemical that you need to add to get your resultant pH. The basic numbers that you need are starting ph, starting alkalinity, strarting temperature and the molecular weights of the chemicals that you are using. I have used a particular book. I find it accurate. I have even done tests to confirm its accuracy. There are examples in the book on how to use the tables. I asked this same kind of question 25 years ago. I live in Toronto and decided to go to our City reference library. Did a search and found the book I was looking for. I think I could have gone to the U of T engineering library. But I just checked on line. They do not have the book. It was like finding a needle in a haystack because I did not know where to start. Remember back in those days it was not that easy to find things like today. I am glad I took the effort to find this information. It has really helped me out professionally in the things I do. Go to this site for the name of the book https://www.amazon.com/Emerson-Alkalinity-Changes-....

RE: pH control-neutralization calculation

If you live in a big city you might be able to find this book at the library or at the university. I would scan the pages and save it in your laptop. It is not that big a book. Very handy way of having that information at your fingertips...forever.

RE: pH control-neutralization calculation

You can assume the worst case. That would mean that the entire 30 cubic meters batch is 100% caustic soda and then you calculate the quantity of acid to neutralize the caustic soda.

RE: pH control-neutralization calculation

Wow...that is an expensive book! The book is very good and worth every penny. As I said, they have examples of how to use the tables. It is very easy to use. I am so glad that we have a top notch public library system in Toronto.

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