Sewage sludge recycling as part of the circular economy

The disposal and further processing of sewage sludge is being increasingly strictly regulated by the legislator, because the importance of recovering finite resources is steadily increasing. As population density increases, so does the amount of sewage sludge produced and, at the same time, the demand for food and the associated need for fertilisers.

The thermal recycling of sewage sludge by SÜLZLE KOPF SynGas makes a significant contribution to closing the nutrient cycle. On the one hand, valuable phosphorus can be recovered, and on the other hand, sewage sludge can continue to be used as a CO2-neutral energy source.
The prerequisite for obtaining phosphorus-rich, detoxified ash is mono-utilisation of the sludge. Here we set new standards with our patented process. Through the thermal sewage sludge utilisation of SÜLZLE KOPF SynGas and the resulting synthesis gas, the energy bound in the sewage sludge can be used far more efficiently. Thus, high efficiencies in energy recovery from sewage sludge are possible even in small sewage treatment plants. Due to the reduced energy costs, the sewage sludge utilisation plant pays for itself within a few years.

Small sewage treatment plants in particular are unable to find a suitable, financially viable solution among the previously established technologies for thermal treatment. A compact, decentralised utilisation plant on the site of the sewage treatment plant creates long-term cost and disposal security. The sewage sludge utilisation process fits optimally into the processes of the sewage treatment plant and ensures flexible energy use on site.

Customers such as cement and power plants, which have used dried sewage sludge as an additional fuel up to now, will also face the challenge of phosphorus recovery in the future. The upstream connection of the SÜLZLE KOPF SynGas fuel gas module separates the material flows in the incineration process and thus ensures that the phosphorus is removed. Finally, an ignitable synthesis gas is made available for the auxiliary firing.