Parker Coral Sea, Owner'S Manual

Page: 191 / 248

TMM-310
Guidelines for RO cleaning
TORAY REVERSE OSMOSIS ELEMENTS section page:
2
/
2
Operation, Maintenance and Handling Manual rev.: 105
v
ersion: October 2012
Selection of cleaning procedure
Once contamination of the membrane surface has been identified, the correct
cleaning procedure must be selected.
z
If foulants are believed to be metal hydroxides, such as ferric
hydroxide, or calcium scale, acidic cleaning procedures are
promising, (see TMM-320: Instructions for chemical cleaning,
TMM-330: Citric acid cleaning procedure).
z
If foulant is believed to be organic or biological fouling, a
cleaning procedure with detergents is recommended, (see
TMM-320 Instructions for chemical cleaning, and TMM-
340.Dodecyl Sodium Sulfate (DSS) Detergent Cleaning
Procedure).
Evaluation of the effectiveness of cleaning
Descriptions of various cleaning procedures are given in TMM-320: Instructions
for chemical cleaning. If the recommendations are followed, good results are
generally obtained in many cases. Pressure drop across the modules should be
reduced to initial value while permeate flow rate and solute rejection will be
restored.
If performance is not sufficiently improved after cleaning, a different cleaning
procedure may lead to a better result. Foulants will frequently adhere to
membrane surface or remain in spacer material. Final removal may take several
successive cleaning procedures. As foulants may be present as layers on the
membrane surface, alternating citric acid and detergent (acid/ alkali) cleans are
frequently more effective than repeated cleans with only one type of cleaner..
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Coral Sea Owner's Manual
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