Anaerobic digester for organic waste
AssigneeEnergy Harvest AS
InventorsEugene M. Dale, Jerry A. Malstrom
Life of this patent
Estimating the term…
Abstract
Organic wastes, such as animal manure, are fed into an elongated digester tank at one end thereof in slurry form. The slurry slowly moves to the other end of the tank for subsequent disposal. During the residence time in the tank decomposition of the waste occurs yielding methane gas and carbon dioxide. A cover over the digester collects the gas generated. A heat exchange arrangement causes transverse stirring of the slurry as it passes through the tank enhancing the decomposition process. Scum suppressors on the surface of the slurry prevent interference with the formation and release of the methane gas. The settling of solids is controlled by the use of gas jets disposed along the bottom of the tank.
Claims8
An anaerobic digester for producing combustible gas from organic waste comprising:
- (a) a digester tank having an input end adapted to receive a fluid slurry containing said organic waste and an output end from which the slurry is discharged from the tank, said tank including an air tight flexible membrane and an outlet therefrom disposed over said tank into which the gas passes as it evolves from the slurry;
- (b) means for introducing the slurry into said tank at said input end and means for removing the slurry from said output end after passage through said tank;
- (c) means for heating the slurry to a temperature conducive to anaerobic digestion of the organic wastes thereby to generate said gas;
- (d) means for suppressing the formation of scum on the surface of the slurry while resident in said tank, said suppressing means including a plurality of panels floatably positioned on the surface of said slurry, whereby scum is maintained below the surface of the slurry in a wet condition to ensure digestion;
- (e) means for maintaining the panels in position to maintain spacing therebetween and means to prevent dislocation thereof when the slurry is above or below normal levels in said tank.
Dependencies are inferred from the claim text.