Post denitrification is often applied for existing plants revamping when nitrates in the effluent are too high. The problem is diffused, especially when the effluent discharge occurs in sensible areas, where nitrogen limits are very stringent, or when the plant design has been done without a pre-denitrification section.

The dynamic post-denitrification process on a sand filter involves the growth of bacteria on the filter media and the removal of nitrates through transition in anoxic conditions in the presence of a nutrient substrate, where nitrogen gas is developped.

Application of the post-denitrification process to continuous sand filters rather than classic permanent bed filters offers the main benefit of continuous functioning, guaranteeing stationary conditions for the de-nitrifying biomass.

Austep applies its competence and skill in order to find a solution, that is able to solve the problem with reliability and low investment cost. The process produces as by-effect the suspended solids filtration of the effluent.