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Useful Informaon about…..
Gravity Fed Filtraon
Gravity Fed Filtraon is designed to remove high levels of iron and manganese commonly found in many
ground water supplies. The gravity fed system ulises the basic principles of iron removal, which is aeraon
followed by filtraon. Oxygen rich water converts iron from its dissolved state (Ferrous) to its un-dissolved
state (Ferric), whereby the iron forms large parcles big enough to be removed by filtraon. However, the
results may vary and will depend largely on the type of water you have.
IRON & MANGANESE
Iron and manganese are common elements found in nature, and combined, make up around 6% of the
Earths crust. Iron and manganese are essenal nutrients in our diets and even though they are non-harmful,
when levels exceed potable limits bad tastes, odours, heavy staining and deposing can occur. This can
make water un-useable.
Because of other natural elements and minerals in water, iron and manganese can be present in many
different forms. This can dramacally effect how it’s removed. To help idenfy the type of iron and manganese, certain parameters need to be tested. It’s crical to have the water tested correctly. To ensure results
bench-tesng or even small-scale pilot tesng may also be required.
Gravity Fed Filtraon
How to get beer results
The problems with many gravity fed systems is the way they are set-up. To opmise the system and improve water quality the following ps can help:
•
Aeraon: Although a natural oxidiser for iron and manganese removal, it’s slow and very weak. Success with air depends greatly on the waters pH, organics and temperature. To enhance air be0er the
waters pH might need to be adjusted and to combat organics and temperature, a longer retenon
me maybe necessary.
•
Retenon Time: This is important because air is slow. The longer the water has before filtraon the
more likely the iron and manganese will form oxidised parcles for filtraon.
•
Filtraon: The type of filter-aid is important, as this gives the filter its ability to remove oxidised parcles. Common filter sand is frequently used, however there are more advanced medias available with
larger la9ce structures and greater surface areas making them be0er at removing iron and manganese.
•
Bask-Washing: An inadequate supply of water for backwashing cannot li: or clean the filter-aid correctly. Over-me this can lead to a loss in performance and eventually media fouling. The surface area
of a filter determines the back-wash volume, the greater the surface area, the greater the volume required. Air scouring can help break-up and clean medias more efficiently while also picking up any
short-falls in water volume. Air scouring can also reduce the total amount of water needed for backwashing.
Aeraon:
pH adjustment improves
oxidisaon.
Backwashing
High volume backwash pumps
and air scouring improves
media cleaning.
Retenon:
Longer retenon me
improves oxidisaon
Filtraon:
Advanced medias
remove more
For Further informaon Free Phone Ecoworld on 0800-109-202