Patent ID: 6608184
Filing Date: 2003-08-19
Classification: C02F,C05F,Y02A

Abstract:
The process for producing carbohydrates from dry sewer sludge by the process consisting of mixing, heating and reacting by the following steps:(1) dried sewer sludge is ground into small particles; (2) aqueous sodium hydroxide is added to and mixed with the sewer sludge; (3) sewer sludge is heated to remove excess water; (4) sewer sludge is heated to 100Â° to 240Â° C. for 5 to 60 minutes; (5) water is added and mixed to form an aqueous solution; (6) carbon dioxide is added and mixed with the aqueous solution to react with the sodium hydroxide to form sodium carbonate; (7) carbohydrates form crystals and the aqueous solution is filtered off thereby recovering the carbohydrates; (8) lime oxide is added and reacted with the aqueous solution of sodium carbonate to form sodium hydroxide and calcium carbonate which precipitates, and the aqueous sodium hydroxide is decanted off to be reused; (9) calcium carbonate is heated in a lime kiln to recover calcium oxide for reuse and the carbon dioxide is collect for reuse.