Energy efficiency analysis using the example of the WPP Burgau
As part of Bavaria's Action Plan 2020 the Bavarian State Ministry of the Environment and Health ("Bayerische Staatsministerium für Umwelt und Gesundheit) wants to help Bavaria’s thermal waste treatment plants to increase their energy efficiency. bifa used the example of the waste pyrolysis plant (WPP) in Burgau to analyse possibilities for optimising energy use and pointed out ways in which they can be used. bifa focussed on optimising use of waste heat.
About MPA Burgau
The district waste management of the Landkreis Günzburg administrative district has operated a pyrolysis plant for thermal treatment of wastes in its Burgau location since 1983. The energy acquired is used to heat the low-temperature rotating drums. The remaining thermal energy is converted into electricity via a steam turbine. Due to the system design, a large proportion of the energy is produced as condensation heat at a temperature level of around 60 °C.
In recent years the efficiency of the pyrolysis process has been improved continuously. A significant part of the condensation heat is already used to provide hot water to heat the greenhouses of a neighbouring market garden. Analysis of the courses of action available for further use of the waste heat stream extend from various areas such as drying and burning sewage sludge, downstream conversion into electricity by means of the ORC process, generation of cold using sorption refrigeration systems, supplying external customers, temporary storage of heat to bridge stoppage periods and to balance peaks and light loads.
The results of this energy efficiency analysis can be applied generally to all Bavaria’s thermal waste treatment plants. It was found that very detailed examination of the existing basic parameters is necessary before the listed optimisation alternatives are considered. Realisation of one or several of the completely innovative concepts would help to make Bavaria the pioneer of sustainable energy supply based on thermal waste treatment.