Abstract: The present invention is directed to methods and systems for pre-treating sewage sludge in a sewage treatment works (STW) to facilitate anaerobic digestion. These methods include (a) passing sewage sludge through one or more pre-treatment devices, wherein each pre-treatment device comprises (i) a passage of substantially constant diameter having an inlet in fluid communication with the STW and an outlet; and (ii) a transport fluid nozzle communicating with the passage and adapted to inject high velocity transport fluid into the passage; (b) passing the sewage sludge treated in step (a) to an anaerobic digester; and (c) collecting methane produced in step (b). Other methods are also provided for pre-treating a bio-degradable waste flow.

Abstract: The present invention provides methods for increasing soluble chemical oxygen demand (sCOD) in sewage sludge. These methods include passing the sewage sludge through one or more devices that contains (a) a hollow body provided with a straight-through passage of substantially constant cross-section, the passage having an inlet end and an outlet end for the entry and discharge respectively of the sewage sludge, (b) a transport fluid nozzle substantially circumscribing and opening into the passage intermediate the inlet and outlet ends thereof, (c) a transport fluid inlet communicating with the transport fluid nozzle for the introduction of a transport fluid, and (d) a mixing chamber being formed within the passage downstream of the transport fluid nozzle. The sewage sludge is then passed through a digester.