Parker Coral Sea, Owner'S Manual

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TMM-240
Shutdown considerations for RO systems
TORAY REVERSE OSMOSIS ELEMENTS section page:
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Operation, Maintenance and Handling Manual rev.: 105
Version: October 2012
Shutdown considerations for RO systems
1) When shutting down a RO system the system should be thoroughly
flushed at low pressure with sufficient quality flushing water to displace
all the brine from the pressure vessels. (see TMM-250 Flushing
procedures)
Acceptable water for flushing are: Pre-treated feed water (refer to table
240-1), or RO product water
Water used for flushing should not contain any oxidants, Maintain the
flush water solution pH between 3-8.5 at all times
Table 240-1: Suggested flushing water for various RO
feed water treatment system
RO feed water type Flushing water
Sea water Pre-treated feed water
Brackish water Pre-treated feed water
Waste water RO product water
High pH Feed water,
(such as 2nd pass
high pH feed water)
x
Pre-treated feed
water without NaOH
x
1st pass product
water without NaOH
2) Ensure membrane elements are kept wet, properly sanitized, and
protected from freezing at all times during the shut-down period.
3) Ensure guidelines for temperature and pH of the preservative solution
are observed during shut-down period.
Take care that product back pressure never exceeds 0.05 MPa at any time.
Product back pressure should be assessed on an individual stage basis.
Product backpressure is defined as product pressure minus feed resp. brine
pressure.
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Coral Sea Owner's Manual
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