Clack Water Specialist CI WS1, Installation, Operation, Maintenance Manual

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5. Technical Information
Note: Check the service and backwash flow rates (see technical information). If the
service flow rates are exceeded or the backwash flow rate is not correct then the filter
may not work correctly.
5.1 Process and Operating Data.
Birm
Vessel size
C1054 C1248 C1354 C1465 C1665 C1865 C2160 C2469 C3072 C3672
Service flow rate - m3/hr 0.6 0.9 1.0 1.2 1.6 2.0 2.7 3.6 5.6 8.0
Backwash flow rate - m3/hr 1.1 1.8 2.0 2.3 3.4 3.9 5.7 6.8 11.4 17.1
Birm can be used for iron and manganese removal by oxidation (up to 15ppm). It requires a
pH of 7 or more for iron removal and pH 8 for manganese removal (it uses dissolved oxygen
in the water to oxidise the metal). As it acts a catalyst it is not consumed so Birm doesn’t
require regenerating or topping up (does require backwashing). Birm also has the advantage
of acting as a filter removing relatively high levels of turbidity. It is advised not to use Birm in
combination with chlorination and the water should be free of oil, polyphosphates and
hydrogen sulphide. Alkalinity should be greater than twice the sulphate and chloride level and
the organic loading should be below 5ppm. If the pH of the water is too low pH correction
maybe required by adding a pH correction media such as Juraperle or Corrosex. Birm
requires a dissolved oxygen of at least 15% of the iron and manganese content to work..
Freeboard 30% to 50%
Filox
Vessel size C1054 C1252 C1354 C1465 C1665 C1865 C2160
Service flow rate - m3/hr 2.0 2.7 3.3 4.0 5.3 5.7 6.1
Backwash flow rate - m3/hr 1.8 2.3 3.1 3.7 4.7 5.4 5.7
Filox can be used for iron and manganese and hydrogen sulphide removal by oxidation. It
requires a pH of 7 or more for iron removal and pH 8 for manganese removal plus a dissolved
oxygen level of at least 15% of the iron and manganese content. It needs a high backwash
flow rate to remove the oxidised iron and manganese but can cope with high service flow
rates. Filox can also cope with chlorinated water. NSF certified, Freeboard 30% to 50%
pH Media
Vessel size C1054 C1248 C1354 C1465 C1665 C1865 C2160 C2469 C3072 C3672
Service flow rate - m3/hr 0.6 0.9 1.0 1.2 1.6 2.0 2.7 3.6 5.6 8.0
Backwash flow rate - m3/hr 1.1 1.8 2.0 2.3 3.4 3.9 5.7 6.8 11.4 17.1
Water with a pH below 7 is acidic and can damage copper pipe-work and heating systems.
Raising the pH will neutralise the water stopping the corrosivity, removing the metallic taste.
The pH is raised by passing the water through a vessel containing slowly dissolving calcium
and magnesium salts. These salts slowly dissolve into the water 're-mineralising’ the water
and naturally raising the pH. Make sure that there is 30% freeboard.
Juraperle: a granular media made up of 99.4% calcium carbonate. It has a superior
performance to limestone due to its micro-crystalline structure and dissolves very
slowly. Juraperle is consumed and from time to time new media should be added.