Environmentally friendly and state-of-the-art: Flue gas cleaning
In order to minimise emissions of harmful gases during flue gas cleaning, S2E chose state-of-the-art technology. A dry flue gas cleaning system is used for the Halle-Lochau mono-incineration plant. This variant does not produce any wastewater from flue gas cleaning, which is an innovative and sustainable advantage.
The flue gas purification system consists of:
- Fabric filter for pre-separation of the fly ash
- Dry additive dosing: addition of activated coke and hydrated lime to the flue gas stream (sorption reactor).
- Particle recirculation and conditioning
- Fabric filter (sorption filter)
- Ash removal and bufferingg
The quasi-dry, conditioned sorption stage with the dosing of hydrated lime and activated coke in a reactor forms the second stage. The powdered sorbents are separated and removed in the second fabric filter together with the pollutants bound to them, whereby the separated particles are partially recirculated. This results in more efficient separation of the pollutant components while at the same time reducing the need for sorbents.
The cleaned flue gas is conveyed via the induced draught fan into the stack, where the pollutant gas and particle concentrations are continuously measured, which are then evaluated and recorded in the emission measuring station. The dusty ashes are stored separately in silos and can then be transported away.
With the selected flue gas cleaning process, the pollutant gases, dust, heavy metals and polychlorinated dibenzodioxins and dibenzofurans (PCDD/F) can be separated in a very economical way. This design of flue gas cleaning ensures compliance with the required emission limits according to the 17th Ordinance on the Implementation of the Federal Immission Control Act (BImSchV).
Phosphorus recovery: Ashes as valuable raw material
Sewage sludge mono-incineration achieves the highest rates of phosphorus recovery with simultaneous destruction of all pollutants – with subsequent phosphorus recycling from the ash produced. The sewage sludge ash from fluidised bed incineration is very low in pollutants and represents a significant phosphorus carrier. Thus, it will be a valuable feedstock for the future production of fertiliser from phosphorus.
High-quality recycling of phosphorus-containing ash is the future
It can already be observed that, with regard to the mandatory recovery of phosphorus after the expiry of the transitional periods from 2029 or 2032, the mono-incineration of sewage sludge, together with the high-quality recycling of the phosphorus-containing ashes produced, is being intensively pursued in Germany as a matter of priority.
In order to keep an eye on the future obligation to recover phosphorus already today, sludge2energy GmbH is looking at sustainable and efficient recycling routes for the phosphorus-containing ashes.
Cold commissioning since mid-July 2021, hot commissioning at the end of September: The milestones of the project
- November 2018: Application for construction of the plant
- November 2019: Start of construction
- 15 and 16 January 2021: Installation of the fluidised bed furnace
- 31 March 2021: Boiler pressure test passed
- June 2021: Completion of assembly of all plant components and testing of all pressurised component groups
- Since mid-July 2021: Cold commissioning
- Mid-October 2021: First sludge fed, followed by performance tests and trial operation
- Start of regular operation and handover to WTE Betriebsgesellschaft mbH scheduled for 01 March 2022.
Learn more about the this project and the sustainable sludge2energy process at www.sludge2energy.de.