Pyreg GmbH

Sewage sludge to phosphorus fertilizer - Waste and Recycling - Sludge Management

Stricter limits, obligation to recycle phosphorus, rising waste disposal costs due to capacity bottlenecks: The recycling of sewage sludge is becoming increasingly sophisticated. We support you with our leading-edge carbonisation technology: With a PYREG system, the dried sewage sludge is carbonised, hygienised and completely recycled into a phosphorus fertiliser substrate approved throughout Europe. The technology has already proven its worth at three wastewater treatment plants in Germany and the USA, but is worth 50,000 p.e. (population equivalent).

The P500 for sewage sludge is a compact plant in series production and fulfils all necessary approval guidelines with its exhaust gas purification system.
In the PYREG process, the sewage sludge is completely recycled into a fertiliser substrate with plant-available phosphorus that is approved throughout Europe. Further treatment is not necessary.
A PYREG system is designed as a decentralised sewage sludge recycling solution: The sewage sludge can be used where it accumulates – directly at the sewage treatment plant. This saves complex logistics (volume reduction by more than 60%). The system can also be scaled up as required.
With the decentralised PYREG technology, all recycling steps remain in one place and you can calculate, plan and control the process in a targeted manner.

The carbonisation of sewage sludge may seem to go against the trend in the age of “decarbonisation”. Rest assured: Exactly the opposite is the case. With carbonisation you actively protect the environment and the climate.


The sewage sludge is thermally treated and hygienised. Hormones, germs, drug residues, microplasty or the like are eliminated.
The recycling process is autothermal, only energy from the sewage sludge is used to operate the plant. Phosphorus is recovered as a secondary raw material in a form available to plants. During carbonisation, a large part of the carbon contained in the sewage sludge is bound over the long term and spread as fertiliser substrate, sequestered in the soil for centuries.
Pyreg carbonation forms the basis for the ultimate circular economy.
This is – together with the advantages – in the Pyreg Carbon Cycle clarified: