TORAY MBR
Instruction Manual
06-G-MB2-NHPAF-220801
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a = 1,000 mm (= 10 kPa, 100 mbar), b = 3,000 mm (= 30 kPa, 300 mbar)
PIA readings;
Filtration (pump ON)
Relaxation (pump OFF)
P1 (kPa)
29
30
P2 (kPa)
-15
-10
In this case, TMP is calculated as follows;
TMP= (P1
Filtration
- P1
Relaxation
) - (P2
Filtration
- P2
Relaxation
)= (29) - (30) - [(-15)-(-10)]= 4 kPa
* In case water level is stable, P1
Filtration
is equal to P1
Relaxation
. Then TMP is;
TMP = P2
Relaxation
- P2
Filtration
= -a - P2
Filtration
d. Air supply unit (such as a blower)
This unit supplies air to the air diffusers of "NHPA Series" module. The air flow rate
supplied to the module should be always within the range of "Scouring Air Flow
Rate" indicated in Table III-3.
e. Air flow meter.
An air flow meter is recommended to be installed to check the flow rate of the
scouring air supplied to the module. In case of operating several “NHPA Series”
modules simultaneously in a train, it is advised installing, at a minimum, one air flow
meter for each train.
f. Suction pump
A suction pump is required in the case of pump suction configuration. To achieve an
accurate designed filtrate flow rate, the suction pump should be fitted with a VFD
controller. The use of a volute pump (centrifugal pump) or volumetric pump (screw
pump) with self-priming functions is recommended.
g. Level sensor
Level sensors are required to be installed in the membrane tank to monitor and
control the liquid level of the membrane tank and to facilitate calculating TMP via the
PLC.
h. Siphon breaking device on filtrate piping
When using a suction pump, it may be necessary to have a means to break the
filtrate siphon if the filtrate discharge point is lower than water level of the membrane
tank. This siphon flow has to be avoided and the filtrate flow has to be stopped
whenever the pump stops.
It is required that a screen with openings of 3.0 mm or less be
installed prior to the membrane tank.
A mesh type screen is
recommended. Avoid any overflow or waste carryover at all the times.
CAUTION
!
