Both technology and environmental awareness drive legislation for wastewater treatment. Now, the leap from 20/30 (BOD: Biological oxygen demand, mg/l / SS: suspended solids, mg/l) to 10/10 or even 5/5 is possible due to a different design approach. For years, the sewage treatment plant market was dominated by systems from (septic) tank suppliers, but now an engineering company from Holland (DMT Environmental Technology) has implemented its experience from large wastewater treatment plants to design small scale sewage treatment plants (STPs). This downscaling trajectory started in 2000 with concrete systems and developed to light weight modulated systems. The current generation STPs engineered by DMT are two different systems, both extensively tested with a CE-certification period of 40 weeks at the independent university “Van Hall Institute”, an accredited test house based in the Netherlands. Analyzed discharge pollution concentrations showed that qualities lower then 10/10 (The DMT IWOX® Premium-Standard) and even lower than 5/5 (mg/l BOD/SS) (The DMT IWOX® Superior) were reached with complete nitrification. The DMT IWOX® Superior also removes Nitrogen (N) by denitrification, which is in line with the scope of the European Framework Directive. Future development of treatment technology will lead to further reduction of SS, BOD, Nitrogen and Phosphate. It will also become possible to remove pathogens in the discharge. Viltra and DMT are already anticipating these possibilities by developing special filters and Ultra Filtration membranes for their STPs. With the continuous improving STP’s, easily capable to reach better discharge qualities then described by legislation, the main question at this moment is : is the current legislation out of date?
Viltra IWOX systems engineered by DMT - The next standard in small scale wastewater treatment