Sludge dewatering and pasteurization process
AssigneeFKC Co., Ltd.
InventorRoger J. Olson
Life of this patent
Estimating the term…
Abstract
A process for dewatering and reducing pathogens in liquid waste sludge having a liquid component and a sludge solids component. Alkaline material is added to the liquid waste sludge. Flocculent may then be mixed with the liquid waste sludge. The liquid waste sludge is then fed into a screw press having a screw. The screw simultaneously heats and dewaters the liquid waste sludge for a sufficient period of time and at a predetermined temperature for the sludge solids component from the screw press to be pasteurized. An apparatus is also provided for carrying out the process for dewatering and reducing pathogens in liquid waste sludge.
Claims15
A process for dewatering and reducing pathogens in liquid waste sludge, having a liquid component and a sludge solids component, comprising:
- adding an alkaline material to the liquid waste sludge;
- mixing flocculent with the liquid waste sludge;
- feeding the liquid waste sludge into a screw press having a screw;
- and
- simultaneously heating the screw and dewatering the liquid waste sludge in the screw press for sufficient period of time and at a predetermined temperature for sludge solids component from the screw press to be pasteurized, wherein the heating of the sludge solids in the screw press is for a time period equal to or greater than defined by the following equation:
- D=131,700,000/(100.14t)
- where “D” is the number of days for a minimum of 20 minutes and “t” is a temperature in Celsius at a minimum of 50 degrees.
A process for dewatering and pasteurizing liquid waste sludge, having a liquid component and a sludge solids component, comprising:
- feeding the liquid waste sludge into a screw press;
- and
- simultaneously heating and dewatering the liquid waste sludge in the screw press for sufficient period of time and at a predetermined temperature for sludge solids component from the screw press to be pasteurized, wherein the heating of the sludge solids in the screw press is for a time period equal to or greater than defined by the following equation:
- D=131,700,000/(100.14t)
- where “D” is the number of days for a minimum of 20 minutes and “t” is a temperature in Celsius at a minimum of 50 degrees.
A process for dewatering and reducing pathogens in liquid waste sludge, having a liquid component and a sludge solids component, comprising:
- adding an alkaline material to the liquid waste sludge;
- feeding the liquid waste sludge into a screw press having a screw;
- and
- simultaneously heating and dewatering the liquid waste sludge in the screw press for sufficient period of time and at a predetermined temperature for sludge solids component from the screw press to be pasteurized, wherein the heating of the sludge solids in the screw press is for a time period equal to or greater than defined by the following equation:
- D=131,700,000/(100.14t)
- where “D” is the number of days for a minimum of 20 minutes and “t” is a temperature in Celsius at a minimum of 50 degrees.
Dependencies are inferred from the claim text.