NIRE-170-1-6
31
air is found not to be evenly distributed between modules it may be necessary to
modify the air line header piping inside diameter to achieve uniform air distribution
to each module.
c. Check the system controls and associated control components for proper operation
and proper sequence of operation.
d. Start the clean water filtration process. At the initial operation of suction pump,
priming (filling the suction piping with water) may be needed for proper pump
suction and in that case avoid pressurizing the filtrate side of "NHP210
Series” over
10kPa. Measure and record the trans-membrane pressure and water temperature at
designed filtration rates (
at normal, maximum and minimum flow rates
). It is
beneficial to periodically record flow rates and TMP values.
e. Stop the clean water filtration process and discontinue the air supply as soon as the
above tests have been satisfactorily completed.
Do not conduct clean water operation for a long time. Clean water
operation may cause membrane clogging.
Keep the membranes wet once they get wet. If the membranes are
allowed to dry out, the permeability of the membranes may be
permanently reduced.
Avoid pressurizing the filtrate side of "NHP210 Series
” over 10
kPa.
2. Seeding Sludge Injection
Do not attempt to produce filtrate from any wastewater that has not first been seeded with
activated sludge. Failure to do so will result in severe clogging of the membrane pores
Follow these steps when seeding sludge in the membrane tank with activated sludge:
(1)
Locate a nearby wastewater treatment facility that treats wastewater similar in
composition to the wastewater to be treated with the new “NHP210 Series”. Make
arrangements to transport some of that healthy, activated slugged from the
nearby wastewater facility to the facility needing the seeding sludge. Activated
sludge with higher MLSS concentration and higher MLVSS/MLSS ratio is
preferable.
Initial MLSS concentration of the membrane tank should be at
least 3,000 mg/L or higher. Higher than 7,000 mg/L is preferred.
(2)
Supply the seed sludge through the <3mm screen to the tank.
(3)
Begin feeding the raw wastewater as soon as possible after the activated sludge
has been introduced into the membrane tank.
CAUTION
!
CAUTION
!
CAUTION
!