ProKläR-mission: Process optimisation of sewage sludge incineration systems for raw material recovery and emission reduction
In January 2023, the joint project “ProKläR-mission – Process optimisation of sewage sludge incineration systems for raw material recovery and emission reduction” started. The sub-project “Process optimization for nitrous oxide reduction and improvement of ash quality” is being worked on by TEER.
The project aims at researching process-side measures to reduce nitrous oxide emissions from stationary fluidised bed furnaces for thermal treatment of sewage sludge. At the same time, the ash quality is to be optimised with the aim of phosphorus recovery. An increase in the fluidised bed temperature is essential for this. To realise this, an online agglomeration monitor will be researched and tested in order to reliably observe the fluidisation state and thus realise higher temperatures in the fluidised bed. Tests in two laboratory plants – a fluidised bed incineration system (45 kWth) and a fluidization furnace (100 kWth) – will firstly serve as a proof of concept of the agglomeration monitor and secondly show the influence of temperature increases and additive usage on nitrous oxide emissions and ash quality. Finally, the optimal operating parameters and additives determined in the laboratory plants as well as the agglomeration monitor are tested in practice in three industrial scale plants.
The project will be carried out in collaboration with the Chair of Energy Process Engineering at Friedrich-Alexander-Universität Erlangen-Nürnberg and Küttner GmbH & Co. KG. Associated partners in the project are Eigenbetrieb Stadtentwässerung Stuttgart, Thermische Verwertung Mainz GmbH and Gemeinschaftsklärwerk Bitterfeld-Wolfen GmbH. The project is funded for three years by the Federal Ministry for Economic Affairs and Climate Action.