Use of HCl in bioprocess

[ildarn]

Could anyone advise if it is possible to use HCl in low concentrations in bioprocesses without having the corrosive effect on the stainless steel equipment (tanks, pipes etc.)? The idea would be to acidify the bioprocess feeding media. The estimated HCl conc. would be 0.07 - 0,21 N HCl.

 

[CKOne]

Hi ildarn

Have you tried H2SO4 as an acidifier instead? Have had problems with HCl before with a bacterial process, we found it actually inhibited bug growth.

If you are in the design phases maybe consider using a higher grade steel - 316 or 2205, if you were looking at using 304 originally?

 

[ildarn]

Thanks Chillipip,

but the idea is to quit using H2SO4 as this gives too much SO4 in the process.

So using HCl would be still good.

ildarn

 

[StoneCold]

ildarn
What about using acetic acid or citric acid?
Both are easier on stainless.


StoneCold

 

[ildarn]

Hi,
tanks for your attention,
H2SO4 is what we actually want to prevent (due the waste water issues, SO4 load etc.).

 

[CKOne]

Does your nutrient mix contain phosphates? If so, you could replace with phosphoric acid. Even if you don't need phosphates, it generally won't do any harm to the bugs. Some of the organic acids can cause toxicity problems with the bugs, you may need to do a tox test first.