TORAY UF
Instruction Manual
06-G-MB2-HFUG-B2315AN-220930
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3. Toray Maintenance Cleaning
Instead of chemical dosing for every backwash, soaking the membrane in a chemical solution
several tens of minutes a day is also effective for membrane performance retention. This
process is called Toray Maintenance Cleaning (TMC). The TMC is usually held following the
backwash and air-scrubbing which does not contain the chemical dosing. The frequency and
soaking time of the TMC mainly depends on the raw water quality (Normally once a day for 20
minutes. Please contact us for any technical support if necessary). Fig. 6 shows a typical
example of flow diagram for the TMC.
(1)
Open the air exhaust
valve (V-4) and the drainage valve (V-3).
(2) Open the backwashing valve (V-6), run the NaClO feed pump and the backwashing pump
to feed the chemical enhanced backwash water to the membrane module. The chemical
is usually sodium hypochlorite, and the dosing ratio should be up to 300 mg/L as Cl
2
for
Fig. 6. Flow diagram for the TMC
