4 replies to this topic

[anni]

Working in a bottled water company and we had installed a new RO system last year.

However, high total plate count (>500cfu/ml) & pseudomonas aeruginosa had been detected from the system since first week of operation.

Sanitation (using hydrogen peroxide/peroxyacetic acid) had been applied to the system but it seems it only suppress the microbe for a few days. If the RO system has not been used for 2-3 days and pseudomonas aeruginosa is detected again when the system is on.

 

Has anyone experienced the same issue or any advices on this issue?

 

Thank you!!

[Tony-C]

Hi Anni,

 

A few questions:

 

What is the loading going into the system?

Are you using UV sterilisation anywhere in your system?

Do you have a CIP facility on the RO plant?

 

Kind regards,

 

Tony

[anni]

Hi Anni,

 

A few questions:

 

What is the loading going into the system?

Are you using UV sterilisation anywhere in your system?

Do you have a CIP facility on the RO plant?

 

Kind regards,

 

Tony

 

 

We've also tested water loading into system. For total plate count, it's around 200-300 cfu/ml and without detection of pseudomonas aeruginosa.
However, when the water flow to the RO membrane, the total plate count seems increasing. We took the water sample after passing through the system and there is decrease in total plate count (usually around 50-100 cfu/ml), sometime pseudomonas aeruginosa can be detected.

 

UV sterilization is not within the system but it's applied in RO water tank.

 

the only CIP is sterilization with the sanitizer every 3 weeks.

[Tony-C]

Hi Anni,

 

Sounds like the membrane is the source of the contamination, are you detecting Pseudomonas aeruginosa in the RO water tank as well?

 

Also, if Pseudomonas aeruginosa had been detected from the system since first week of operation I’d be having the manufacturers in to investigate for you.

 

Kind regards,

 

Tony

[anni]

Hi Anni,

 

Sounds like the membrane is the source of the contamination, are you detecting Pseudomonas aeruginosa in the RO water tank as well?

 

Also, if Pseudomonas aeruginosa had been detected from the system since first week of operation I’d be having the manufacturers in to investigate for you.

 

Kind regards,

 

Tony

 

Yes Tony, Pseudomonas aeruginosa can be detected in RO water tank as well but it is not very often.