Microbial contamination in acid tank(CIP)
I have encounter a problem where I've found some bacteria in my concentrated acid tank mainly for the CIP purpose. Few sampling was done but still getting same result. Does anyone encounter the same problem or I need to have your suggestion to caunter attack this issues. thank you.
We have not encountered this problem at the brewery I currently work for but I can speculate on your problem as I am a trained microbiologist. The first thing I would check would be the actual acid concentration as it may not be as high as you think it is. If it is not, simply increasing the concentration of acid may resolve your problem. If the acid level is what it should be, I would suggest removing the acid from the tank and then performing a chlorine wash which should remove any bacteria able to survive in such an environment. There are not many bacteria that can survive in high acid so chances are your tank is not at the concentration it needs to be so as I stated before, that would be my first guess. Good luck to you.
The first post is correct, emptying the CIP tank and doing a chlorine wash. I might also add to replace the tygon tubing site glass on the tank if you have one. Bacteria and especially mold can indeed grow in acid CIP tanks. Good luck and let us know how it goes.
What type of acid is in the tank and at what concentration? I find it hard to believe that you'd see a bacterial problem in an acid tank.
Also be extremely careful about chlorine washing an acid tank. That's asking for trouble.
I had a conversation with this individual a while ago and from what i remember his acid concentration was not high enough, so by increasing his acid his problem was solved. I do agree with you that chlorine washing an acid tank is dangerous - but if you know what you are doing it should not be a problem. just need to remember to wear protective gear including a respirator in case something was to happen.
Firstly, if you are storing your acid in a stainless steel tank, then using hypochlorite to debug it is likely to corrade the SS unless you rinse it carefully first, then preferably give it a caustic wash, rinse then treat with hypo. After treating with hypo in a caustic solution, rinse off VERY carefully before refilling.
Re the contamination, we have suffered this in dilute solutions (1 - 2 % acid). The bugs develop a degree of resistance to the acid. Adding some peracetic acid to the dilute acid should counteract the growth OK. I wold be extremely surprised to find anything growing in concentrated acid though.