The Energy from Waste Plant in Poznań is being built with a view to the residents and environment. The investment will significantly reduce the amount of landfilled waste, and will additionally create thermal energy and electricity during incineration. Thanks to the use of the latest technologies and a specialist emissions treatment system, the EfWP will be completely safe for the environment and to humans.
Author: Fot. Majątkowe Prawa Autorskie SITA Zielona Energia Sp. z o.o.
The EfWP's technical parameters:
- plant capacity: 210 000 Mg/year
- nominal capacity of one thermal processing line: 13.5 Mg/h
- number of thermal processing lines: 2
- nominal calorific value: 8 400 KJ/kg
- plant operating time: 7 800 h/year
- expected value of the production of energy from thermal waste processing
- approx. 126 000 MWh/year of electricity and up to 300 000 GJ/year of thermal energy in cogeneration (average annual value)
A schematic overview of the EfWP:
- Specially adapted vehicles deliver municipal waste to the EfWP.
- After weighing, the vehicles with the waste drive to the unloading hall, where they are directed straight to the waste bunker. Both the unloading hall and the bunker are vacuums, which eliminates the risk of unpleasant odours escaping outside.
- Before its transformation process, the waste is collected in the bunker. The bunker is a sealed, concrete moat that is recessed into the ground. The air from the unloading hall and bunker is sucked out and carried to incineration under the grate.
- The waste from the bunker is passed to the furnace's hopper using an overhead crane; it then goes to the furnace's grate, where the incineration process takes place. The furnace's grate is movable (the grate bars move) and inclined, which makes the waste move towards the bottom of the grate during incineration. The high temperature – 850ºC – means that the incineration process is safe, and limits the possibility of the formation of harmful substances and their emission into the atmosphere
- Incineration generates very hot air, which flows through the boiler. This air heats water and converts it into steam, which is later used in the energy recovery process.
- The steam from the boiler is directed to a steam turbine, where electricity is created. Some of the steam is used to make thermal energy that is then supplied to the local heating network
- During incineration, exhaust gases are created; these are passed through their treatment systems. There is a decrease in nitrogen oxide emissions, flue gas desulfurisation, decrease in heavy metals and organic pollutants i.e. dioxins, furans, and flue gas dust removal using a high-capacity bag filter.
- Dust caught in the bag filter is then processed further. This waste is stored at a special landfill or used as backfill in salt mines.
- Slags remain after the waste incineration; these go to a deslagger that is integrated with a grate. There they are cooled and passed on for processing. Metals are recovered from the slags from the incinerated waste, and the remaining slags can be used further, after being first prepared, for example as aggregate in road construction.
- All of the parameters of the processes that take place at the EfWP are constantly monitored.