STERAPORE 5600 Series (FF) Instruction Manual
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Chapter 3
Chemical Cleaning
This section describes cleaning equipment such as chemical tanks and chemical pumps and cleaning
procedures.
WAR N I N G
Handle each chemical according to its SDS
＊
.
Wear protective clothing when handling elements and modules.
Be sure to wear protective clothing such as goggles and rubber gloves when handling chemicals such
as sodium hypochlorite (NaClO) used for membrane cleaning or acid. If any of these chemicals come
into contact with your hands, eyes, or other body parts it may cause loss of eyesight or chemical burns.
In this case, thoroughly rinse the affected part and consult a doctor.
Mixing sodium hypochlorite (NaClO) and acid releases chlorine gas, which is very dangerous. Do not
mix these chemicals under any circumstances. Be sure to take this into account when designing the
system.
*
SDS (Safety Data Sheet) is a type of Safety Data Sheet. Safety data sheets are documents that provide
information about the characteristics of chemicals and how to handle them, and are submitted when transferring
or supplying products that contain the applicable chemicals to other businesses.
3-1
Chemical Cleaning
This section includes chemical cleaning procedures, notes and other information.
Be sure to handle each chemical according to its SDS.
C AU T I O N
Monitor the suction pressure of the module and prevent the pressure from exceeding the set
value (the initial value of suction pressure -15 kPa (trans membrane pressure index, negative
pressure)). The system must be configured so an alarm is triggered if the suction pressure
exceeds the set value. If this happens, perform chemical cleaning immediately to restore the
suction pressure.
Normally, NaClO is used as the chemical solution for cleaning MBR systems, as clogging is primarily
caused by organic matter. However, as clogging caused by inorganic matter increases gradually when
the system is used for long periods, acid cleaning using acidic chemicals should be performed when
necessary.
There are three types of chemical cleaning using NaClO and/or acid.
①
Maintenance cleaning (NaClO)
②
Recovery cleaning (NaClO and acid)
③
Chemical soak cleaning
Normally, system performance is maintained using a combination of maintenance cleaning (
①
) about
once a week and recovery cleaning (
②
) once every 3 months (or when suction pressure exceeds the set
value). These are both cleaning in place (CIP) methods: A chemical solution is injected from the
permeate pump side (hereinafter referred to as "permeate side") with the module immersed in the
membrane tank.
If the trans membrane pressure is not restored during recovery cleaning (
②
), or sludge has adhered
between membranes due to device problems or other reasons, perform chemical soak cleaning (
③
) by
removing the module from the tank, washing it with water, and then immersing it directly in a chemical
solution.