C-Green

C-Green is a Swedish clean-tech company founded in 2014 that has developed a process to convert wet organic waste, like sludge, into a solid, dry, and sterile biocoal. The firm was established by Fredrik Öhman, with later involvement from founders Erik Odén and Fredrik Lundqvist.

The company's core technology, OxyPower HTC™, utilizes hydrothermal carbonization (HTC) to mimic and accelerate the natural process of coal formation, converting wet biomass in hours rather than millions of years. This process is designed to be energy-efficient, running on the chemical energy within the sludge itself without needing external heat once started. The technology addresses the significant environmental and cost challenges associated with managing sludge from municipal wastewater treatment plants, agriculture, and industries like pulp and paper. These waste products often contain hazardous substances and emit substantial greenhouse gases.

C-Green's process transforms sludge into HTC hydrochar, a carbon-enriched biocoal that is sterile, odorless, and has only 20-30% of the original volume. This biocoal can be used as a renewable biofuel, a soil amendment, or for nutrient recovery, particularly phosphorus, a critical raw material. The company operates on a business model that involves providing its biorefineries to clients such as waste handlers, industrial facilities, and municipalities. For instance, C-Green installed its first industrial-scale plant at a Stora Enso pulp mill in Finland and is developing a demonstration plant with waste management company Ragn-Sells in Sweden. The company has also established a partnership with Next Rung Technology to expand into the North American market.

Keywords: hydrothermal carbonization, sludge management, waste-to-energy, biocoal, cleantech, wet waste conversion, nutrient recovery, circular economy, OxyPower HTC, hydrochar, biosolids treatment, sustainable waste management, phosphorus recovery, greenhouse gas reduction, industrial sludge, wastewater treatment, biofuel production, soil improvement