Abstract: Apparatus and process is provided for hydrolyzing sludge from water treatment and for conditioning the hydrolyzed sludge for optimal anaerobic digestion. Methods provided include dewatering to produce dewatered sludge, hydrolyzing the dewatered sludge in a steam fed process, preheating the dewatered sludge before hydrolysis with sludge-to-sludge heat transfer, and cooling and diluting the sludge using sludge-to-water heat transfer and water injection, and anaerobically digesting the hydrolyzed sludge. Apparatus provided includes a generally vertically oriented counterflow sludge-to-sludge heat exchanger, a hydrolysis reactor and associated source of steam, sludge-to-water heat exchangers, and a dilution unit. Temperature and pressure sensors are configured to command various variable flow pumps and valves for controlling the process.

Abstract: Apparatus and process is provided for hydrolyzing sludge from water treatment and for conditioning the hydrolyzed sludge for optimal anaerobic digestion. Methods provided include dewatering to produce dewatered sludge, hydrolyzing the dewatered sludge in a steam fed process, preheating the dewatered sludge before hydrolysis with sludge-to-sludge heat transfer, and cooling and diluting the sludge using sludge-to-water heat transfer and water injection, and anaerobically digesting the hydrolyzed sludge. Apparatus provided includes a generally vertically oriented counterflow sludge-to-sludge heat exchanger, a hydrolysis reactor and associated source of steam, sludge-to-water heat exchangers, and a dilution unit. Temperature and pressure sensors are configured to command various variable flow pumps and valves for controlling the process.