Railing and static sieve – removal of coarse solids
Decantation, grit chamber – technique for physical removal of settleable solids (e.g. sand and slurry);
Flotation – technology for physical-chemical separation of particles which are naturally floatable. It may apply the dissolved air technique to increase efficiency. (e.g. oil, fats)
Equalization - it is used for the equalization of flow and pollutant load in secondary treatment. It may be necessary adjustments of pH and conductivity to improve efficiency of further treatment.