GIRE-097-2-2
59
X.
TROUBLESHOOTING
Most of troubles in the operation of “TMR090 Series” are related to abnormal membrane
scouring aeration, too late chemical cleaning, lack of maintenance of the pretreatment
system. The following table shows such troubles and countermeasures against them:
Table IX-1 Troubleshooting
Problem
Cause
Action
1
The air diffusion rate is below
the standard level.
The blower is broken
Check the blower.
The air diffusers are
clogged.
Clean the air diffusers.
2
The air diffusion is uneven in
the module or between
modules.
The air diffusers are
clogged.
Clean the air diffusers..
Uneven valve opening of
the air supply line to each
module.
Adjust the vale opening rate.
The bottom of the element
block is stuck with trash.
Check the pretreatment system.
Inspect the module.
Correct operation and maintenance works
of the pretreatment system.
3
The permeated water flow rate
has decreased. Or the
trans-membrane pressure has
increased.
Membrane clogging.
Carry out chemical cleaning.
Sludge accumulated on the
membrane surface
because of uneven air
diffusion.
Inspect the blower and clean the air
diffusers to improve air diffusion.
Carry out chemical cleaning.
Abnormal properties of
sludge have worsened its
filterability.
Improve sludge properties.
・
Adjust the excess sludge discharge
rate.
・
Prevent entry of abnormal
components, such as oils.
・
Adjust the BOD load.
・
Adjust the raw water quality (add
nitrogen, phosphorous, etc.)
４
The concentration of
suspended solids in the
permeate water has increased.
An element or tube has
fractured.
Seal the element and manifold nozzle
*1
.
A leakage has occurred in
the permeated water
piping.
Inspect the faulty part
*2
and correct the
fault.
Germs are generated on
the membrane or the
permeate line.
To clean the permeated water piping,
inject into it a sodium hypochlorite solution
with an effective chlorine concentration of
100 to 200 mg/L.
*1: Even if a cause is found in the tube, there still is the possibility of contamination inside the element. Thus,
seal the element and manifold nozzle.
*2: To check the piping joints and welds for leakage with a pressure being applied, be careful not to apply
pressure to the membrane modules.
