Sludge treatment / digestion

Efficient waste water treatment today requires the use of modern technologies and the combination of individual processing components into an efficient overall system. This includes in particular the treatment of sewage sludge with the aim of securing optimum energy and material use and/or recovery. In addition to the classical methods of sludge treatment such as thickening and dewatering, STULZ-PLANAQUA has innovative, energy technologies and technologies optimized for waste material for the disintegration, digestion, dewatering and drying of the resulting sludge in sewage treatment plants. In combination with energy improvements in the mechanical and aerobic biological waste water treatment and use of renewable energies such as wind power and photovoltaics, it is thus possible to operate sewage treatment plants energy self-sufficient, if necessary even with excess energy. For energy and thermal sewage gas use, STULZ-PLANAQUA provides complete cogeneration plants, including gas treatment.

A major component on the road to energy self-sufficient sewage treatment plant is the energy and waste material-optimized treatment of sludge filtrate water. For this purpose, STULZ-PLANAQUA has the DEMON® process, which has now been implemented in more than 10 plants for the treatment of sludge water, landfill water leachate, waste water from biogas plants and industry.

The DEMON ® process provides the maximum possible shortening of classical nitrification/denitrification. Only approx. half the ammonium is oxidized by means of atmospheric oxygen to nitrite. The other half is then converted with the help of the formed nitrite to elemental nitrogen. Compared to conventional nitrification/denitrification, the process needs only 40% of the energy and no external carbon source (e.g. methanol) for this purpose. In addition, the sludge volume is significantly lower.

The DEMON® process has yet another most important climate-related advantage. While other biological processes produce large quantities of carbon dioxide, the DEMON® process even fixes carbon dioxide.