WET - Wastewater & Effluent Treatment for the removal of priority substances

The objectives of the project were to prepare the development of these measures by demonstrating the technical feasibility of:

·  The removal of dissolved organic compounds using coagulants in WWTP-effluent;

·  The simultaneous removal from WWTP-effluent of nitrate and phosphate in a filter bed;

·  The use of activated carbon in granular (GAC) or powdered (PAC) form in WWTP-effluent. GAC is applied in the form of a filter bed. PAC is dosed in line and subsequently filtered from the effluent;

·  The application of advanced oxidation on municipal WWTP-effluent; and

·  Bio filtration at extremely low substrate-concentrations.

Results include:

·  Removal of phosphate by metal salt dosing and nitrate removal using a carbon source supported dentrification process can be combined in a one filter configuration, resulting in a structural achievement of the WFD standards for Ptotal (<0,15 mg Ptotal/l) and Ntotal (<2,2 mg Ntotal/l).

·  The use of Advanced Oxidation Processes resulted in a reduction of medical remnants and pesticides by at least more than 70 % and in a desinfection level up to the hygienic limits set for in the EU Bathing Water Directive (76/160/EEC).

·  Removal of heavy metals and of organic micro-pollutants and suspended solids achieved by using the same combination of techniques.

·  The removal of other priority substances of the WFD has been investigated in the second monitoring phase of the project, in which Advanced Oxidation Processes (using ozone, hydrogen peroxide and uv-light) were tested.