PCA installs iron removal installation at Barry Callebaut
Certain problems can occur when groundwater is used in a production process. One of them is an elevated concentration of iron. Ferrous water is in itself not harmful to our health, but iron gives water an unpleasant taste, odour and colour. Iron also causes deposits on machine parts with which the water comes into contact, and possibly unexpected problems as a consequence. This means iron removal is often unavoidable.
Clean water is also important at Barry Callebaut, the world's largest manufacturer of chocolate and cacao products. Their groundwater contains an excess of iron. As they need this water for the cooling towers and steam boilers, they sought a solution in the form of an iron removal installation to have the softeners work more efficiently.
Iron removal takes place in three phases in the installation that PCA built at the company:
1. The oxidizer or aeration tank
The first phase is aeration and flocculation. The soluble iron is oxidised by the oxidizer air supply and transformed into coarse flocculant. These coarse particles are easier to remove. The speed of this stage depends on the iron concentration in the water and the quantity of oxygen added.
2. The multimedia filter or sand filter
Phase two is the removal of the flakes. The multimedia filter or sand filter is the largest part in the installation. This filter is filled with different types of sand and gravel and a layer of hydro-anthracite. It filters the main contamination from the water.
3. The pyrolox filter
The last phase in the iron removal process is the removal of the last iron residues. This is done by the pyrolox filter. The filter is filled with pyrolox and ensures that the last remains of iron after the multimedia filter are removed from the water.