TORAY UF
Instruction Manual
06-G-MB2-HFUG-B2315AN-220930
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usually sodium hypochlorite, and the dosing ratio should be up to 50 mg/L as Cl
2
.
The flow rate of backwash water is set up in advance for 1.0 to 1.5 times the filtrate flow
rate. Do not exceed Max. Backwash Flow described in Table 4.
(4) After backwashing for a fixed time (normally 30 seconds, up to 60 seconds), close the
backwashing valve (V-6) and stop the backwashing pump.
(5) Open the air exhaust valve (V-4) and the air-scrubbing valve (V-2) for air-scrubbing for a
fixed time (normally 30 seconds, up to 60 seconds).
The air flow rate for air-scrubbing should be within the
range below. Excessive air flow rate may damage the
hollow fiber membrane.
Air flow rate: 3.6 – 6.7 Nm
3
/h, normally 4.5 Nm
3
/h
(2.1 – 3.9 scfm, normally 2.6 scfm)
The maximum required air pressure during the air-
scrubbing for the inside of the module will be 40 kPa (6
psi).
(6)
Close the air-scrubbing valve (V-2) and open the drainage valve (V-3).
(7)
Close the drainage valve (V-3) after the water is all drained out.
(8)
Run the feed water pump and open the feed water valve (V-1).
(9)
Close the air exhaust valve (V-4) after the air is purged from the module.
Constantly monitor filtrate quality during filtration and
stop the operation if abnormal water quality is detected.
In that case, check the integrity of the element with PDT
(Pressure Decay Test) or DAF (Diffusive Air Flow) Test.
The test procedure is provided as the technical
information by Toray.
