Patent ID: 7276148

Claim:
A multi-stage process for the treatment of organic waste comprising: (a) Drying said waste to reduce water content to below 15%; (b) Subjecting said dried waste to a thermochemical liquefaction process in the presence of a recirculating solvent medium at a temperature of about 275° C. to 375° C. and a pressure of up to 10 atmospheres, thereby obtaining gaseous, liquid and solid products; (c) Separating a formed slurry product from condensable gas, water and other liquid fractions boiling out at up to 250° C.; (d) Transferring said slurry product obtained from thermal extraction from step c to a pyrolysis apparatus and treating the same at a temperature of about 350° C. to 500° C. to cause additional thermal destruction of unconvertible organic matter of feed material and heavy liquid fractions obtained in step c and their evaporation and removal from pyrolysis apparatus; (e) Separating vapor products from condensable oil products; (f) Vacuum distillation of oil products from step e for the removal of fractions having a boiling temperature of between 250° C. and 350° C.; and (g) Recirculating a fraction having a boiling temperature of above 300° C. as the recirculating solvent medium for step b.