(DE58902128-G)      In the treatment of sewage sludge, (a) the sludge is dried to the max. attainable amt. of dry matter, followed by fractionated pyrolysis, with (b) low-temp. conversion under anaerobic conditions at 250-350 deg.C to separate the organic C as an oil, and (c) burning of the residue in pure O2 at at least 1250 deg.C and (d) the residual inorganic components are used in finely divided state as substitute for a hydraulic binder esp. cement. Pref. sludge is dried to at least 85% dry matter. Conversion step (b) is pref. at 300 deg.C. Burning (c) is pref. at 1450 deg.C.    ADVANTAGE -   Because of the high energy content of the sewage slurry, the process is almost independent of external energy. The problem of the disposal of sewage sludge is solved by recycling, and pollution of the environment is avoided. The oil can be used as fuel, and the reaction gas, mainly CO2, can be recycled to maintain the anaerobic conditions. Only small amts. of CO2 and nitrous gases are formed in the high-temp.    sintering, and heavy metals remain as oxides in the final residue.    (SU1794061-A3)      In the treatment of sewage sludge, (a) the sludge is dried to the max. attainable amt. of dry matter, followed by fractionated pyrolysis, with (b) low-temp. conversion under anaerobic conditions at 250-350 deg.C to separate the organic C as an oil, and (c) burning of the residue in pure O2 at least 1250 deg.C and (d) the residual inorganic components are used in finely divided state as substitute for a hydraulic binder esp. cement.    Pref. sludge is dried to at least 85% dry matter. Conversion step (b) is pref. at 300 deg.C. Burning (c) is pref. at 1450 deg.C.    ADVANTAGE -   Because of the high energy content of the sewage slurry, the process is almost independent of external energy. The problem of the disposal of sewage sludge is solved by recycling, and pollution of the environment is avoided. The oil can be used as fuel, and the reaction gas, mainly CO2, can be recycled to maintain the anaerobic conditions. Only small amts. of CO2 and nitrous gases are formed in the high-temp. sintering, and heavy metals remain as oxides in the final residue.