Page 155 - Bluebook Sereco english

Water filters

• FSQ
• FCA
• FTG
• FDG www.sereco.it
• ABSWF

The filtration processes considered in this section are ing the only back washing cycle. The back washing
usually used for the tertiary treatments of civil or indus- occurs without any interruption of the normal filtration.
trial sewages. In particular SERECO offers equipment In particular, the FDG type allows very small overall
for the filtration on sand, activated carbon or through dimensions and high specific flow rates; in fact it has a
clothes. In particular the pressure filters FSQ and FCA wide effective filtration surface in very limited areas.
carried out the filtration respectively on sand and acti- SERECO can also boasts a long experience in the
vated carbon. They are used if an effluent with very installation of sand or activated gravity beds, with tra-
good characteristics is required; in particular the FCA ditional back washing carried out with the interrup-
type, combining the filtration to the adsorbing effect tion of the filtering process and insufflating back-
of the activated carbon, noticeably better the sewage washing air and water from adequate nozzles provid-
characteristics with regard the residual load and sus- ed on the bottom.
pended solids. The filtration process on sand or activated carbon can
The filtration on sand or activated carbon is possible be also carried out, in an integrated way, within the
also by using the model FPVR. In this case the filtra- frame of a chemical-physical treatment of CFF type.
tion occurs by gravity and the back-washing system of The sand or activated carbon filters FSQ and FCA types
the filtering bed allows the back washing without inter- are however used for the treatment of the potable
rupting the filtration. water and, sometimes, also in the tertiary treatments
Whereas the filtration through cloth is possible thanks of sewage. In this connection SERECO also boasts a
to two types of filters, FTG and FDG. Both of them are long experience about deferrization and demangani-
gravity filters with zero energy consumption during the zation plants normally used for the potabilization
normal filtration and a very low energy requirement dur- treatments.