A pressurised biological iron removal unit will include (figure 29):

Note: a biological iron removal system will start up more slowly than physicalchemical treatment.

average or high Fe content and low Mn, NH4+ ≤ 1.5 mg · L–1 : biological iron removal followed by intensive aeration and filtration through sand or nitrifying filter bed depending on the water’s precise NH4+ concentration and temperature;

A pressurised biological iron removal unit will include (figure 29):

Note: a biological iron removal system will start up more slowly than physicalchemical treatment.

simple iron removal without sedimentation (aeration-filtration)

Is the deferrization rate (i.e. iron separation) optimal?

Removal of iron (Fe) and manganese (Mn) from water

Removal of iron (Fe) and manganese (Mn) from water

Examples of physical-chemical iron removal systems including open aeration

When H2S is present, it has to be removed either through aeration at the inlet (gravity iron removal), or biologically (pressurised treatment) (see section h2s removal).

average or high Fe content and low Mn, NH4+ ≤ 1.5 mg · L–1 : biological iron removal followed by intensive aeration and filtration through sand or nitrifying filter bed depending on the water’s precise NH4+ concentration and temperature;

The core active components, termed as de-ironizing inducers (Dll), consist of a reducing agent and a precipitating agent.

Physical-chemical iron removal: typical example of a pressurised unit producing 600 m3 · j–1

Partial carbonate removal at a pH in the region of 8 can, therefore, result in total iron removal.