Evaluating new applications of hydrochar in the UK; case study in chirnside

Different applications of hydrochar produced from the sewage and food waste generated by a small town in the UK (Chirnside; 2,250 residents) are assessed. These are: As a solid biofuel used in domestic biomass boilers, use in combined heat and power, as a precusor to activated carbon, and as a soil conditioner. For each application, the process had a positive net energy when using part of hydrochar to power the HTC plant. As a biofuel for domestic combustion, hydrochar would only be able to supply the town with 2.18 % of its thermal energy demand. The highest potential revenues can be obtained when activating all the hydrochar produced (99.08 t yr^-1), with revenues dependant on the characteristics of the final product. Application as a soil conditioner is not certifiable in the UK as of yet and is not the most profitable application. Aging or thermally treating hydrochar for soil conditioner applications should be used to remove phytotoxic compounds.