Mitsubishi STERAPORE 5700 Series Instruction Manual page 27

recovery cleaning. In this case, choose a pump based on the flow rates for both.
■Example of a calculation for the flow rate of a chemical pump per 57M0200FF unit (excluding the
amount corresponding to the capacity of the guide pipe)
Assume that the concentration of undiluted NaClO solution is 12 % and that its specific gravity is 1.19.
 Maintenance cleaning
2
200 m × 2 L/m
 Recovery cleaning
2
200 m × 2 L/m
●
Dilution water pump
This is a pump used to dilute NaClO fed by a chemical pump. Homogeneously mix the dilution water in
an in-line mixer (static mixer) after it flows into the NaClO pipe.
■Design example
Pump type: A variable meter pump. Use a pump that can be used for both maintenance and recovery
cleaning.
■Example of a calculation for the flow rate of the dilution water pump per 57M0200FF unit (excluding
the amount corresponding to the capacity of the guide pipe)
× 2 L/m
2
200 m
3-2-2 Cleaning Process Program
As maintenance cleaning and recovery cleaning are basically performed automatically, it is
recommended to incorporate these processes into a program in advance.
On the basis of the schematic diagram of chemical cleaning equipment (p.25, Figure 3-4), an example of
a time chart for recovery cleaning is shown in Table 3-2 for your reference.
Table 3-2 Reference Example of a Time Chart for Chemical Cleaning Processes
Process Process
number
Filtration
A-①
operation
A Filtration
Filtration
A-②
suspension
Feeding tank
B-①
B Diffuser water
cleaning Discharging tank
B-②
water
Injecting NaClO
C-①
out
C Chemical
C-②
Settling
cleaning
Aeration before
C-③
refiltration
D Recovery Pushing NaClO
D-①
cleaning out
process
Settling
D-②
Aeration before
D-③
refiltration
D-③'
Pushing NaClO
out
STERAPORE 5700 Series (FF) Instruction Manual
2
× 500 mg/L ÷ 12 % ÷ 1.19 g/cm
2
× 3,000 mg/L ÷ 12 % ÷ 1.19 g/cm
÷ 30 min = 13.3 L/min
2
Operation Timer Permeate
setting pump
(minutes)
7
1
0.5
0.5
30
90
0 to 15
30
90
0 to 15
0 to t
3
÷ 30 min = 0.05 L/min
3
÷ 30 min = 0.28 L/min
Membrane RAS
scour pump
blower
○ ○ ○
× ○ ○
× × ○
× ○ ○
× × ×
× × ×
× ○ ○
× × ×
× × ×
× ○ ○
× ○ ○
Chapter 3 Chemical Cleaning
NaClO Dilution MV1 MV2
pump water MV3
pump
× × ○ ×
× × × ×
× × × ×
× × × ×
○ ○ × ○
× × × ×
× ○ × ×
○ ○ × ○
× × × ×
× × × ×
× ○ × ○
○: Pump/blower is operating, MV is open
×: Pump/blower is stopped, MV is closed
MC: Maintenance cleaning
MV4 Remarks
Repeat A-① and
×
A-② alternately.
×
○
Go to A－① after
×
completion.
×
Not required during
×
MC
Go to Ａ－① after
×
completion.
×
×
Go to the process
×
A－① after completion.
Implement when
necessary. Start at
×
same time as above.
" t " differs according
to the pipe capacity.
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