Solid Radioactive Waste Strategy Report.pdf - UK EPR

EPR UK
N° NESH-G/2008/en/0123
REV. A PAGE 61 / 257
Following monitoring, clean water leaving the cross flow filtration system can be directly
discharged or sent for additional treatment. The concentrates resulting from the process require
additional conditioning prior to disposal.
Application
· Treatment of all types of liquid effluent containing dissolved and undissolved solids.
Design Data
· System throughput: 10 m³/h (typical);
· Decontamination factor: 10 to1000 (system and nuclide specific, typical values).
Advantages
· Volume reduction;
· High decontamination factor;
· No secondary waste;
· Proven and compact design;
· Automatic operation.
Disadvantages
· Concentrated sludges/slurries have to be conditioned prior to disposal;
· Membrane can be prone to blocking or fouling.
7.3.4 Liquid Effluent Treatment By End of Pipe Filtration
End of pipe filtration systems are used to remove suspended solids from liquid effluent
containing low concentrations of suspended solids [Refs. 36 and 37]. The use of this technique
is not economical for liquid effluent containing high quantities of suspended solids as the filters
are rapidly blinded under these circumstances.
The used filter cartridges are sent for conditioning and disposal. The volume of used filter
cartridges generated from the use of this technique can be minimised by the use of self-cleaning
filters and filter configurations that are amenable to back flushing.
The typical minimum practical pore size of end of pipe filters used for cleaning of the radioactive
liquid effluent is approximately 1 to 5 µm. The smaller the filtration pore size the more difficult it
is to accommodate the volumes and flow rates required during liquid effluent treatment.
Following monitoring, the liquid can be directly discharged or sent for additional treatment.