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Convert wet sludge into clean bio-coal.

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Växlarevägen 31, 170 63 Solna, Sweden



Thematic field:

Energy from Chemical Fuels

Market segment:

Bioenery & waste to energy, Industry

The start-up

C-Green’s solution converts wet sludge from sewage treatment and the pulp and paper industry into clean bio-coal using a hydrothermal carbonisation process.

The need

Waste-water treatment plants and industries worldwide produce sewage waste with residue sludge difficult to dewater, containing bacteria, pharmaceuticals, phosphorous, toxins, heavy metals. Disposal costs are high and environmental targets not reached.

The solution

A compact, robust and efficient process solution based on hydrothermal carbonisation that separates phosphorous (for further use in fertilising applications) and heavy metals from sludge, degenerates toxins, deactivates pharmaceuticals and transforms the remaining sludge into bio-coal. It enables waste-water treatment plants to reduce their operating and capital cost, while meeting the environmental target for sludge management.

The value proposition

  • Cost-effective sludge management saving 10 to 30% vs traditional waste disposal costs.
  • Easy-to-use, small, scalable one-size-fits-all solution.
  • Energy-efficient process.
  • Environmental-friendly: turns harmful sludge into homogenous biofuel with a high energy density for power production at CHP plants.

Related News

C-GREEN and partners to build the world’s first sludge-free wastewater treatment plant
Swedish tech company C-Green Technology AB together with the municipality-owned water and wastewater company Roslagsvatten and the Swedish Environmental Research Institute IVL have… Read More
C-GREEN and partners to build the world’s first sludge-free wastewater treatment plant