Plants for industrial wastewater treatments
According to the type of water to be treated, we can divide these plants into two main groups:
A) biological systems: the nature of these systems is similar to that for civil waste, with particular attention to the pre-treatment, which may include:
- Thin grilling (textile industry)
- Flotation for fat removal (dairy industry)
- Oversized storage and mixing tanks (when there are qualitative and quantitative discontinuity of the water).
B) Chemical-physical systems, including:
- Traditional chemical-physical plants (neutralization plants, clariflocculation)
- "FENTON" plants, especially suitable in treating water containing:
- Dyes
- Surfactants (anionic, cationic and nonionic)
- Phenols
- Formaldehyde
- Substances with very low biodegradability.
The FENTON plants
These systems are mainly composed of the following phases:
- Storage and homogenization tanks
- Reaction tank (with a very low pH), where are dosed chloride or ferrous sulfate and hydrogen peroxide
- Neutralization tank, dosing lime
- Flocculation tank, dosing of polyelectrolyte
- Final sedimentation tank (with or without overhead crane)
- Tank for sludge storage and mechanical dehydration
- Final filtration:
- Sand filters
- Activated carbon filters (F.C.A.)