To achieve climate protection goals, the use of wastewater heat provides a huge and largely untapped potential for the development of resource-efficient building heating. The idea of wastewater heat recovery with heat pumps is certainly not new. Since the 1980s, centralized systems in Germany, Switzerland and the Scandinavian countries have been using wastewater heat, either collected in sewers or in wastewater treatment plants.
The wastewater temperature is higher than most other regenerative energy sources such as water or geothermal energy and reaches an average temperature of over 21 ° C when it leaves the building. Wastewater is a stable source of renewable heat supply throughout the year.
So, in the city of Mosty, the administrative building and the air pumping station of the sewage treatment facilities are now heated and receive hot water by recuperating heat from the wastewater entering the treatment. This became possible after the installation of a heat pump and replacement of the heating system as part of an environmental initiative. Heat is removed from the sewage undergoing preliminary treatment. The custom-made heat exchanger is housed in a «settling tank».
The incoming wastewater heats the heat carrier in the heat exchanger and the resulting heat energy enters the heat pump and is used to heat water for hot water supply and heating buildings. Additional thermal renovation of two buildings now also saves the heat generated.
Saving is at least 18.2 Gcal per year of thermal energy due to thermal renovation of buildings and 8760 kWh per year of electricity due to the use of waste water heat. The new system also improves the quality of ambient air by eliminating air pollutant emissions by approximately 0.785 tons per year, including greenhouse gases by 0.517 tons per year (compared to the old heating system).
The system also allows to stop using 12.4 tons of briquettes and 39.3 sq. m³ of wood per year due to the creation of the possibility of heat supply with environmentally friendly heat based on alternative energy sources without the use of fossil fuel combustion.
But the result of the implementation of the ecological initiative was not only an economic effect. Within the framework of the project, the partner of the environmental initiative State Educational Institution “Center for Correction and Development Education and Rehabilitation of Mosty” was equipped with multimedia equipment and educational videos that help to form the environmental consciousness of the younger generation.
Children with special psychophysical development got the opportunity of visual «green» education in the framework of the curriculum «Man and the World», «Orientation in the outside world / Fundamentals of life» and extracurricular activities. Through the holding of information and training events, they will be provided with equal opportunities for active participation in the socio-ecological life of society, “green” learning will be adapted, attention will be focused on the necessary skills and abilities for the maximum possible independent life in harmony with nature.
Within the framework of the initiative, lessons-disputes on environmental topics «Save energy — save the world» were also held at the State Educational Institution «Secondary School No. 5 of the city of Mosty», State Educational Institution «Lunno Secondary School named after Hero of the Soviet Union Ivan Sheremet» . During the lessons, the children learned about the problems associated with climate change, got acquainted with the environmental initiative and went on a virtual tour of their city’s sewage treatment plants through a presentation.
At the State Educational Institution “Pravomostovskaya Secondary School”, students were told about renewable energy sources, as well as energy and resource conservation within the framework of the information and training event “Alternative energy sources and environmental protection”.
The ecological initiative “Reducing greenhouse gas emissions by installing a heat pump at the sewage treatment plant in the city of Mosty” was implemented by the organization of the public association “Belarusian Society of Disabled People within the framework of the project “Civic engagement in environmental monitoring and improving environmental management at the local level”, funded by the European Union and implemented by the United Nations Development Program in Belarus in partnership with the Ministry of Natural Resources and Environmental Protection of the Republic of Belarus.