STP Glasing

Sewage treatment plant Glasing - A recycling oriented energy concept

In the sewage treatment plant in Glasing, in the region of Guessing, waste water of the member communities of the sanitary district “Mittleres Strem und Zickenbachtal” is being cleaned for many years. Two years ago the plants technology was brought up to the state of the art and the cleaning capacity was increased.

The next step will be the development and implementation of a sustainable sewage sludge disposal concept. We expect that soon the agricultural application of sewage sludge will be forbidden. This is why we want to establish a thermal disposal.

The traditional way is to combust the sewage sludge in central incineration plants, but this would bring high additional costs for the sanitary district and almost double the charge for the households. Additionally the sanitary district needs to invest in a sewage sludge drying, because only dry sewage sludge can be transported to the central incineration plants. All wooden and dry feedstock as well as sewage sludge are brought into the thermal gasification, all green and humid feedstock are brought into the fermentation.

The residues from the plants (ash, liquid manure) can either be returned as reusable material into the sewage treatment plant or used as fertilizer.

This way primarily the own energy consumption of the treatment plant (heat & electricity, mostly heat for drying sewage sludge and wood) will be covered. The surplus of heat and electricity as well as the liquid and gaseous fuels are either fed into existing systems like the electricity grids, district heating systems or biogas grids, or delivered to gas stations.

To further increase the efficiency of this energy concept, we plan to use the CO2 from the plants, mix it with parts of the cleaned water and create an algae culture with the help of the sunlight. This new technology was analyzed by Güssing’s research group BIOENERGY 2020+ with international support in a multi-year research project and can now be implemented.

The sun is also used in photovoltaic systems on the roofs of the treatment plant buildings (operations building, computing building, sludge press). This electricity - only occurring when the sun shines - will be buffered into battery systems and equally emitted.

The especially for this energy concept created efficiency analysis shows that aside the sustainable disposal, a very positive financial side effect can be achieved by the communities.