Method and apparatus for treating carbonaceous material

An installation for treating carbonaceous material, said installation comprising:

• a HTG reactor suitable for hydrothermal gasification, having a first inlet (Icm1) and a first (Os), second (Og1) and third (Of1) outlets, the HTG reactor being configured to be fed at the first inlet (Icm1) of the HTG reactor with a first carbonaceous material CM1 comprising primary sludge, and to produce:
• an inorganic solid residue, recovered at the first outlet (Os) of the HTG reactor,
• a first gaseous fraction G1 comprising CH4, CO, CO2 and H2 recovered at the second outlet (Og1) of the HTG reactor, and
• a liquid product F1, optionally containing readily biodegradable carbons such as VFAs, recovered at the third outlet (Of1) of the HTG reactor,
• and
• an anaerobic tank, suitable for fermentation or anaerobic digestion, having a first inlet (Icm2), and optionally a second inlet (If), and a first (Od) and second (Og2) outlets, the second inlet (If) of the anaerobic tank and/or the first inlet (Icm2) of the anaerobic tank being in fluid connection with the third outlet (Of1) of the HTG reactor, the anaerobic tank being configured to be fed at the first inlet (Icm2) of the anaerobic tank with a second carbonaceous material CM2 comprising biological sludge optionally hydrolyzed and/or hygienized, and to be fed with the liquid product F1 at the first inlet (Icm2) of the anaerobic tank and/or at the second inlet (If) of the anaerobic tank, and to produce:
• a digestate recovered at the first outlet (Od) of the anaerobic tank and
• optionally a second gaseous fraction G2 containing CH4 and CO2 recovered at the second outlet (Og2) of the anaerobic tank.

A method for treating carbonaceous material, said method comprising:

• a) providing a first carbonaceous material CM1 comprising primary sludge, and
• providing a second carbonaceous material CM2 comprising biological sludge optionally hydrolyzed and/or hygienized,
• b) subjecting the second carbonaceous material CM2 together with the first carbonaceous material CM1 to an anaerobic treatment step, leading to a digestate and a second gaseous fraction G2 containing CH4 and CO2,
• c) optionally a step of separating the digestate of step b) into a liquid fraction and a solid fraction,
• c) subjecting the digestate, and/or the solid fraction of the digestate, to hydrothermal gasification, thereby producing an inorganic solid residue, syngas comprising CH4, CO, CO2 and H2 and soluble and readily biodegradable molecules.