NIRE-170-1-6
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aeration blocks are to be installed,
record each block’s serial number and position within the
tank.
The air diffusers should be installed in a horizontal position to achieve uniform
scouring aeration.
The maximum allowable deviation from dead level for the air diffusers is
3/1,000 on the top surface of the aeration block in both lateral and vertical directions.
(2) Plumbing in Air Diffusers
Prior to plumbing in the air diffusers, please flush all pipes out. The air diffuser should be
connected to the pipe from air supply unit with the flanges. When using polypropylene
diffuser, please consider piping material and regulate the load to the flange connection points
less than 20 kg per flange, in order to avoid distortion, leakage or breakage of the plastic air
diffuser. If the load is higher than the limit above shown, put some supports on the piping to
reduce the load.
One air diffuser is shipped from the factory with two rubber gaskets. Please connect air
diffuser to the air-line using rubber gaskets with the tightening torque of 20 N.m.
After plumbing in the air diffusers, fill the membrane tank with clean water until the aeration
blocks are completely submerged in the clean water. Next turn on the air supply, check to
make certain that the air is being evenly distributed throughout the aeration block.
(3) Installation Element Blocks
Put the element blocks onto the aeration blocks. Joint both of them using provided bolts if
guide rail system is not applied.
When installing double-decked module NHP210-600D, use guide rails certainly and do
not connect upper element block and lower element block. Also do not install upper
element block and lower element block all together. Upper/lower element block has to
be installed one by one to avoid distortion or damage to the element block which may
cause severe accident.
