TDS high / delta p and productivity are OK
TDS high / delta p and productivity are OK
(OP)
Dears
please advise the TDS of my RO becomes high after frequent CIP but delta p and productivity are good I heard there is special treatment for membrane element
Thank you
please advise the TDS of my RO becomes high after frequent CIP but delta p and productivity are good I heard there is special treatment for membrane element
Thank you





RE: TDS high / delta p and productivity are OK
You should concentrate your efforts to reduce the frequency of CIP.
RE: TDS high / delta p and productivity are OK
Normally, cleaning, if properly done, even frequently, should not degrade the membrane salt rejection. I would encourage you to check on your procedure. It must be adapted to the nature of foulants. Also are you doing some normalization to follow the performance reduction of your unit to decide when to clean ?
There exist some specialty chemicals to enhance membrane rejection, check with water conditonning chemicals supppliers.
RE: TDS high / delta p and productivity are OK
Thank you for your answer
In fact, we do CIP when delta P goes high
Could you please tell me more about normalization advantages
Thank you in advance
RE: TDS high / delta p and productivity are OK
Check membrane manufacturers sites like dow or hydranautics. They provide free spreadsheets to do this.
Delta P alone is not necessarily an accurate way to quantify fouling (even if generally speaking its upward variation indicates that something is wrong.)
The problem is that there are other factors at play. For instance temperature will play an important role due to viscosity variations. Salinity also has an influence.
Flow normalization enables you to compare your actual operating conditions to a reference (usually the starting conditions of the unit or the last time you cleaned) while removing the "seasonal" interference. That way you can have a clear view of the evolution of the performance of your unit vs time and can anticipate on the decision to clean.
RE: TDS high / delta p and productivity are OK
It is advisable to do probing test to check whether all membranes were damaged or not
Krunal Bhosale
http://waterengineer.co.in
All about Water and Wastewater Treatment
RE: TDS high / delta p and productivity are OK
Several mechanical damage of the element or permeate tubing can also allow the concentrate to penetrate the permeate.
RE: TDS high / delta p and productivity are OK
RE: TDS high / delta p and productivity are OK
Regards,
Franz
RE: TDS high / delta p and productivity are OK
RE: TDS high / delta p and productivity are OK
RE: TDS high / delta p and productivity are OK
For Fujiwara test check for instance
http://www.membrane.unsw.edu.au/wp-content/uploads...
As for rejection enhancer, I think that Kurita (ex BKGiulini) used to have some specialty for that. It should be some tannin containing formulation that "coats" or adsorbs on the membrane surface.