3M MEMBRANA Liqui-Cel, Инструкция по уборке

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14
Liqui-Cel
®
Membrane Contactors Cleaning Guidelines
VII. Cleaning Protocol for Mineral Deposits Removal
The inlet water should be treated to prevent mineral precipitation. For example, changes in pH
due to carbon dioxide removal may initiate a
precipitation reaction .
If the performance of the contactor decreases and the inlet water source is not treated to remove
minerals, such as calcium carbonate, it is likely that a layer of mineral scale has formed on the
wetted side (normally the shellside) of the contactor. A simple acid cleaning followed by a water
flush should restore the performance. The contactor does not need to be dried after this protocol.
Also, note that phosphoric acid is more efficient for removing hard mineral deposits or other
precipitated deposits.
NOTICE
Avoid contact with surfactants/solvents or oxidants (e.g. ozone, chlorine) to the
hydrophobic membrane to prevent wet-out or oxidation.
Filtered, de-chlorinated, and deionized water is recommended for mixing cleaning
solutions. Water containing metals such as Mg, iron, Al, and SiO
2
may precipitate on to
the membrane surface when there is a pH shift in the water.
CAUTION
To reduce the risks associated with damaging the membrane contactor:
For all 2.5x8-inch, 4-inch and 10-inch membrane contactors, gas side pressure should
never exceed liquid side pressure during cleaning.
Do not expose the membrane to air when liquid or gas temperatures exceed 30° C.
WARNING
To reduce the risks associated with explosion:
Never exceed maximum temperature and pressure ratings. Detailed temperature and
pressure ratings can be found in the Operating Guide at
www.3m.com/liqui-cel .
If cleaning the shellside of the membrane only, the lumenside should be open to
atmosphere.
To reduce the risks associated with chemical exposure:
Use face protection, protective gloves, and appropriate eye protection when handling
and using all cleaning chemicals.
Ensure any tubing or piping used to circulate the cleaning solution is not blocked,
kinked, frayed, cracked or obstructing flow in any way. Ensure the all tubing and piping
connections are leak-free.
Avoid splashing of chemicals while preparing cleaning solutions or during pumping of
solutions.
Cleaning procedures should be conducted using the minimal temperatures and
pressures required to clean the contactor.