TORAY UF
Instruction Manual
06-G-MB2-HFUG-B2315AN-220930
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Take appropriate measures to prevent the mis-operation
or accidents that could cause the chemicals to get into
the product water. Check the piping and correctly
position of each valve before starting the chemical
cleaning.
(7) The standard conditions for chemical cleaning are shown in Table 6.
The concentration and the circulation time shown in Table 6 should be observed.
Otherwise, the membrane module may get damaged and/or the life of membrane may
be shortened.
The cleaning temperature should be 1 to 40 deg C.
The circulation flow rate for each type of the module is as follows.
Flow rate for chemical cleaning: 52.5 L/min (13.8 gpm)
Table 6. Standard conditions for chemical cleaning
Pollutants
Chemicals
Maximum
Concentration
Circulation
Time (hr)
Inorganic substances
Citric acid *
7)
3.0 wt%
1 - 3
Organic substances
Sodium hypochlorite
3,000 mg/L
as Cl
2
(10 < pH < 12)
1 - 3
*7): Besides citric acid, hydrochloric acid (with the maximum concentration of 1.0 mol/L), oxalic acid
(with the maximum concentration of 1.0 wt%), sulfuric acid (with the maximum concentration of 0.05
mol/L), and nitric acid (with the maximum concentration of 0.1 mol/L) are acceptable.
