3M MEMBRANA Liqui-Cel, Инструкция по уборке

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18
Liqui-Cel
®
Membrane Contactors Cleaning Guidelines
IX. Membrane Drying
The drying process involves two steps:
A. Bulk Water Removal
B. Final Drying
Bulk Water Removal quickly removes liquid from the contactor prior to passing the drying gas
through. The purpose of Final Drying is to evaporate any remaining water from the contactor. Dry
air, nitrogen, and carbon dioxide gas can be used to facilitate drying. Tables 8 and 9 provide
reference points for flow rates and drying times.
Vacuum is not suggested for drying as residual water may remain even after several hours.
A. Bulk Water Removal
To reduce the drying time after cleaning, it is recommended that bulk water be removed by
purging the contactor with gas (normally air) at room temperature for a short period of time
(typically, less than one hour). Introduce gas through the top shellside and lumenside ports. See
the
Bulk Water Removal schematic on page 20. Use clean, dry and filtered (0.2 micron) gas at the
flow rates shown in Table 8. Keep the lower lumen and shellside ports open.
Discontinue the gas flow when the water discharge rate decreases to a few drips. Close the
bottom shellside port when finished.
Table 7: Bulk Water Removal Conditions
Liqui-Cel
®
Membrane Contactor Size Gas Flow Rate scfm*
MiniModules and 2 x 6 0.5 scfm (0.84 m
3
/hr)
2.5 x 8 3 scfm (1.7 m
3
/hr)
4 x 13 10 scfm
4 x 28, 6 x 28, 8 x 20 20 scfm (17 m
3
/hr)
8 x 40 40 scfm
8 x 80 80 scfm
10 x 28 and 14 x 28 50 scfm (120 m
3
/hr)
14 x 40 100 scfm
*Maximum gas pressure = 10 psig (0.7 kg/cm
2
)
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 .