AIRE-064-1-4
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(2) Precautions for Element Chemical Cleaning
a. Inject chemical by gravity. Keep the gravity pressure below 10kPa. Avoid forcibly
applying pressure directly with the pump. A higher pressure will damage elements.
b. Submerge the module completely in the tank and inject chemical. Please maintain
the top of the module at least 500 mm below the liquid surface for the safety reason.
c. Though higher temperature gives more effective cleaning, please maintain the
temperature below 40 degree C. Conversely, lower temperature causes poorer
cleaning effects and hampers the recovery of the membrane permeability. Please
try to maintain the temperature of the liquid as high as possible within the range
below 40 degree C.
d. After chemical cleaning, a small amount of chemical remains inside the elements
and the permeate water line. When resuming the filtration operation, please send
back the permeated water to the raw water tank until the permeated water is free
from effects of the chemical (for a period of at least 2 intermittent cycles), or dispose
of it in accordance with applicable legal standards for waste disposal.
If an abnormality is found in the equipment during chemical
cleaning, immediately stop the operation.
If chemical is injected forcibly directly with the chemical feed pump
or by any other means, the internal pressure of the elements will
increase and the elements will get damaged. Be sure to inject
chemical by gravity with the pressure of lower than 10kPa.
Before starting injecting chemical to elements, confirm that the
liquid surface is more than 500 mm higher than the top of the
module.
Stop the aeration during chemical cleaning, or the membrane may
get damaged.
WARNING
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WARNING
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WARNING
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CAUTION
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