Innovation in the Koblenz wastewater treatment plant

Energy self-sufficiency and sustainable phosphorus use


On August 12, 2020 SÜLZLE KOPF SynGas reached an important milestone in the Koblenz project. After successful trial operation, the functional acceptance of the thermal sewage sludge utilisation plant was granted by Stadtentwässerung Koblenz. This confirmed the performance data of the SynGas process and initiated the handover of the plant to the customer. After the five-week plant tour, all those involved in the project were able to enjoy a joint review of the operating data: In 32 days of plant operation, 228 MWh of electrical and 293 MWh of thermal energy were generated from 395 tons of dry sludge and made available to the sewage treatment plant. The thermal sewage sludge utilisation of SÜLZLE KOPF SynGas thus makes a significant contribution to the complete energy self-sufficiency of the entire large sewage treatment plant in Koblenz as an elementary component of the EU-funded pilot project “SusTreat”. The Stadtentwässerung Koblenz and the other project participants play a pioneering role in this project. They demonstrate that sustainability and resource conservation can be achieved at all levels. The innovative technology of SÜLZLE KOPF SynGas has proven to be particularly advantageous for this project.

  • Due to the compact plant design, the module for thermal sludge utilization could be installed directly on the sewage treatment plant site and integrated into the existing network.
  • The process enables a particularly efficient conversion of the energy bound in the sewage sludge by directly converting the synthesis gas produced into electricity in a CHP engine.
  • The monitoring and control of the plant was made easier for the plant operator through the use of state-of-the-art process control technology and the
    required presence times for plant personnel were minimized.
  • Finally, the phosphorus contained in the sewage sludge is discharged via the SynGas ash produced during thermal utilization and can thus be used as an additive in the fertilizer industry, for example. In this way, the raw material phosphorus, which is essential for survival, is returned to the environment without pollutants and the material cycle is closed.

“The high utilization potential of the sewage sludge is thus completely exhausted and makes a climate-friendly sewage sludge treatment possible for sewage plant operators. Where the sewage sludge accumulates, without environmentally harmful transports and at a calculable price.”

Björn van Deest, commercial manager of SÜLZLE KOPF SynGas, on the day of acceptance.