ČSN EN 12255-13

This document specifies the requirements for chemical treatment of wastewater by precipitation/flocculation for removal of phosphorus and suspended solids.
The application of polymers is not described in this document.
This document has not attempted to specify all available practices.
NOTE - Chemical treatment can be performed in combination with primary and more commonly with secondary treatment, but it can also be performed as separate tertiary treatment, usually in combination with filtration. Chemical treatment can provide a potential contribution to the circular economy through the recovery of materials, such as phosphorus, from wastewater or sludge.