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User Manual
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CIP duration
The CIP duration describes the length of time required for the entire CIP process.
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Recovery rate
The recovery rate refers to the net amount of filtrate produced as a percentage of the total amount of
filtrate produced.
Recovery = [Net amount of filtrate produced/ Total amount of filtrate produced] x 100%
4.2 Start Up and Shut Down
Before starting up the system, ensure that:
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All the modules are accounted for and their serial numbers recorded.
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All the modules are securely restrained to the skid.
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All piping connections are secured and well-set with no undue stresses.
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All equipment and instrumentation in the system are calibrated, working properly and in their right
setting.
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For newly installed/ unused modules, the preservative solution inside the module should be drained
before operation.
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The pre-treatment processes are working and that the feed water quality is of acceptable standard.
Starting up the system:
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Firstly, conduct a forward flush at a feed flow rate of approximately 2m
3
/h for every module being
flushed for 15 mins. This is to flush out any residual preservative solution inside the module.
▪
After that, conduct an actual filtration process for another 5 mins. It is recommended that the filtrate
for the first 5 mins be discharged as well to ensure that there is no residual preservative solution inside
the module.
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Subsequently, continue filtration as per normal automated process.
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During startup, care must be taken to prevent sudden surges in pressure within the system. The design
flows/ flux should be reached incrementally. These are so as to prevent pressure build-ups or water
hammering incidences within the system that can lead to membrane, module and/ or component
damage. The same principles should be applied when shutting down the system.
▪
It is recommended that the flow/ flux be between 30
–
60% of the design flow/ flux for the first 24
hours of operation. Only after that should the flow/ flux be increased to the actual design flow/ flux.
Shutting down the system:
▪
Sudden pressure/ flow stoppage should be avoided.
▪
When shutting down a system for short-term purposes (e.g. CIP), the modules must be backwashed
prior to shut down. If the system is to be shut down for a longer term (e.g. overall plant maintenance,
etc.), a Recovery CIP (R-CIP) must be conducted and the modules must be filled with water.
▪
However, if the modules are to be idle for more than 3 days, it is recommended that the modules be
backwashed again or taken down for re-preservation and storage.
