Sustainability considerations in the operation of Wastewater Treatment Plant 'Swarzewo'

The Wastewater Treatment Plant (WWTP) 'Swarzewo' plays a special role in the protection of coastal waters of the Baltic Sea area and the management of solid wastes in the region. This paper discusses several options implemented in the WWTP area in order to achieve sustainability. The first one was the inclusion of WWTP into municipal waste management plan to increase the biogas production and to reduce volume of organic waste in the region. Nowadays, daily production of about 2000 m(3) of biogas is gained. The energy balance shows a considerable benefit from the co-fermentation of sludge with municipal organic wastes. The next goal was to obtain a favorable economical balance of energy and high level of pollution reduction. The last one was the involvement of local communities in a conscious segregation of waste 'at source'. For the purpose of this paper bio-energy production, nutrient elimination, composting, and research, have been selected as indicators of sustainable development. Furthermore, in this study the methods of nutrient recovery from wastewater were explored. Struvite precipitation and compost production were presented as an example of nutrient elimination with 'end of waste' production. Depending on the struvite precipitation conditions, recovery of 4 Mg of phosphorous and 1,8 Mg of nitrogen is possible to obtain annually.