RWE Power AG


In the Gersteinwerk power plant at Werne near Hamm, RWE Power AG uses coal and natural gas to generate power. The three Units #F, G and I are gas-fired, while the Unit #K burns hard coal. In the latter refuse derived fuel (RDF) is co-fired with coal up to 10% of the total thermal input to the boiler. The RDF co-firing leads to a high content of unburned residues in the bottom ash.
The project challenge was to overcome / eliminate a series of problems related to the use of a conventional wet SCC (Submerged Chain Conveyor) for the bottom ash removal and to promote the post-combustion of the unburnt residues present in the bottom ash. This leads to the recovery of a significant amount of energy in terms of ash sensible heat, ash chemical energy from unburnt particles and boiler radiation flux through the throat.
Thanks to the installation of the MAP® (Magaldi Ash Post-combustor) system, the unburned matter in the bottom ash was drastically reduced, thus increasing the boiler efficiency and improving the ash quality that can be sold as a by-product.



RWE Power is Germany’s biggest power producer and a leading player in the extraction of energy raw materials. Their core business consists of low-cost, environmentally sound, safe and reliable generation of electricity and heat as well as fossil fuel extraction.
At the Gersteinwerk power plant RWE Power AG operates Unit #K, a combined-cycle that, thanks to the combination of a steam turbine with a gas turbine, is one of the most efficient conventional power plants. RWE Power banks on a broad energy mix and to a large extent is able to draw on its own raw material base.
This broad energy mix enables the company to act flexibly and successfully and to sustainably manage the targets of climate protection, security of supply and profitability in an increasingly competitive setting. RWE Power pursues the aim of securing its competitive position in the German electricity market by retaining and renewing its generating capacity.



Magaldi’s scope of supply comprised the use of the existing intermediate hopper (additionally equipped with hydraulic bottom doors), the MAP® extractor in place of the existing wet SCC, a primary crusher to grind the bottom ash, an Ecobelt® steel conveyor belt followed by a transfer tank equipped with discharge equipment to load an existing rubber belt.
The MAP® system ensures continuous operation of the boiler in presence of severe post-combustion conditions, improves the entire process of bottom ash handling, meets safety and reliability standards, strongly improves the bottom ash quality to allow its reuse and/or a significant cost reduction for disposal.