Waste pulping system

• US 6,776,365 B2
• Filed: 05/14/2002
• Issued: 08/17/2004
• Est. Priority Date: 03/12/2002
• Status: Active Grant

• Current Assignee: Illinois Tool Works Inc.
• Original Assignee: Premark FEG LLC (Illinois Tool Works Inc.)
• Inventors: Eno, Steven M., Smith, Neil B.
• Primary Examiner(s): Rosenbaum, Mark
• Application Number:
  US10/145,473
• Publication Number:
  US 20030173432A1
• Time in Patent Office: 826 Days
• Field of Search: 241/46.17, 241/21, 241/46.15
• US Class Current: 241/46.15
• CPC Class Codes: B02C 18/0092 for waste water or for garbage
• CPC Class Codes: B02C 23/36 the crushing or disintegrating zone being submerged in liquid
• CPC Class Codes: D21B 1/345 Pulpers
• CPC Class Codes: D21B 1/347 Rotor assemblies

Abstract

In a waste pulping apparatus, an impeller assembly comprises a rotating blade for pulping solid waste to form a slurry, the rotating blade having an axis of rotation, a base and a plurality of ears that axially extend away from the base. The impeller assembly also includes a sieve ring having axially opposed first and second ends, an inner cylindrical surface and an outer cylindrical surface, where the sieve ring encircles the base of the rotating blade at the first end so that a portion of the ears are radially spaced inside the inner cylindrical surface so that the ears rotate within the sieve ring. A plurality of pumping vanes are also provided for pumping the slurry, where each pumping vane has a pumping surface that rotates radially outside the outer cylindrical surface of the sieve ring. Preferably, the pumping vanes can be easily changed to allow for various head condition while providing a predetermined pumping capacity.

Claims

1. An impeller assembly for a waste pulping apparatus comprising:

a rotating blade for pulping waste to form a slurry, the rotating blade having an axis of rotation, a base and a plurality of ears that axially extend away from the base;

a sieve ring having axially opposed first and second ends, an inner cylindrical surface and an outer cylindrical surface, wherein the sieve ring encircles the base at the first end and at least a portion of the ears are radially spaced inside the inner cylindrical surface so that the ears rotate within the sieve ring; and

a plurality of pumping vanes for pumping the slurry, wherein each pumping vane has a pumping surface that rotates around the outside of the outer cylindrical surface of the sieve ring.

2. An impeller assembly according to claim 1, further comprising a stationary blade adjacent to the sieve ring inner cylindrical surface and in close proximity to the ears of the rotating blade.

3. An impeller assembly according to claim 1, wherein each ear axially extends past the second end of the sieve ring to form a distal end opposite the base, wherein the ears further comprise winglets connected to the distal ends of the ears.

4. An impeller assembly according to claim 3, further comprising a stationary blade adjacent to the inner cylindrical surface at the second end of the sieve ring and axially extending from the second end of the sieve ring and in close proximity to the rotating blade, the stationary blade having a top surface opposite the second end of the sieve ring, wherein the winglet has a bottom surface that passes within a predetermined clearance from the top surface of the stationary blade.

8. An impeller assembly according to claim 1, wherein the sieve ring includes sizing holes, and wherein the sizing holes have a diameter of between about 1.3 cm and about 1.9 cm.

9. An impeller assembly according to claim 1, further comprising interrupter bars connected to the inner cylindrical surface of the sieve ring so that the interrupter bars project radially inward and are in close proximity with the ears of the rotating blade.

5. An impeller assembly for a waste pulping apparatus, comprising:

a rotating blade for pulping waste to form a slurry, the rotating blade having an axis of rotation, a base and a plurality of ears that axially extend away from the base;

a sieve ring having axially opposed first and second ends, an inner cylindrical surface and an outer cylindrical surface, wherein the sieve ring encircles the base at the first end and at least a portion of the ears are radially spaced inside the inner cylindrical surface so that the ears rotate within the sieve ring; and

a plurality of pumping vanes for pumping the slurry, wherein each pumping vane has a pumping surface that rotates radially outside of the outer cylindrical surface of the sieve ring;

wherein each pumping vane has a leading leg, a middle leg and a trailing leg, wherein a rear portion of the middle leg is directed to the outer cylindrical surface of the sieve ring so that there is a predetermined clearance between the rear portion of the middle leg and the outer cylindrical surface, and wherein a rear portion of the trailing leg is directed away from the outer cylindrical surface.

6. An impeller assembly according to claim 5, wherein each leg is generally planar.

7. An impeller assembly according to claim 5, wherein the pumping surface is provided on the trailing leg of the pumping vane.

10. A waste pulping apparatus comprising:

a tank for containing liquid and solids to be pulped;

a slurry chamber adjacent to the tank, the slurry chamber having a volute;

a sieve ring mounted to the tank at the slurry chamber, the sieve ring having axially opposed first and second ends, an inner cylindrical surface, and an outer cylindrical surface, wherein the second end is mounted to the tank so that the first end and a portion of the cylindrical surfaces are within the slurry chamber;

a rotating blade for pulping waste to form a slurry, the rotating blade having an axis of rotation, a base, and a plurality of ears that axially extend away from the base;

wherein the first end of the sieve ring encircles the base of the rotating blade and at least a portion of the ears are radially spaced inside the inner cylindrical surface of the sieve ring so that the ears rotate within the sieve ring;

a stationary blade adjacent to the inner cylindrical surface at the second end of the sieve ring and axially extending from the second end of the sieve ring, wherein the stationary blade is in close proximity to the ears of the rotating blade; and

a plurality of pumping vanes for pumping the slurry out of the volute of the slurry chamber, wherein each pumping vane has a pumping surface that rotates around the outside of the outer cylindrical surface of the sieve ring.

11. A waste pulping apparatus according to claim 10, wherein the ears axially extend past the second end of the sieve ring to a distal end opposite the base of the rotating blade, further comprising winglets connected to the distal ends of the ears.

12. A waste pulping apparatus according to claim 11, wherein the stationary blades have a top surface opposite the second end of the sieve ring and wherein the winglet has a bottom surface that passes within a predetermined clearance from the top surface of the stationary blade.

14. A waste pulping apparatus according to claim 10, wherein the sieve ring includes sizing holes, and wherein the sizing holes have a diameter of between about 1.3 cm and about 1.9 cm.

15. A waste pulping apparatus according to claim 10, further comprising a flange integrally attached to the second end of the sieve ring, wherein the flange is mounted to the sieve ring.

13. A waste pulping apparatus comprising:

a tank for containing liquid and solids to be pulped;

a slurry chamber adjacent to the tank, the slurry chamber having a volute;

a sieve ring mounted to the tank at the slurry chamber, the sieve ring having axially opposed first and second ends, an inner cylindrical surface, and an outer cylindrical surface, wherein the second end is mounted to the tank so that the first end and a portion of the cylindrical surfaces are within the slurry chamber;

a rotating blade for pulping waste to form a slurry, the rotating blade having an axis of rotation, a base, and a plurality of ears that axially extend away from the base;

wherein the first end of the sieve ring encircles the base of the rotating blade and at least a portion of the ears are radially spaced inside the inner cylindrical surface of the sieve ring so that the ears rotate within the sieve ring;

a stationary blade adjacent to the inner cylindrical surface at the second end of the sieve ring and axially extending from the second end of the sieve ring, wherein the stationary blade is in close proximity to the ears of the rotating blade; and

a plurality of pumping vanes for pumping the slurry out of the volute of the slurry chamber, wherein each pumping vane has a pumping surface that rotates radially outside of the outer cylindrical surface of the sieve ring;

wherein each pumping vane has a leading leg, a middle leg and a trailing leg, wherein a rear portion of the middle leg is directed to the outer cylindrical surface of the sieve ring so that there is a predetermined clearance between the rear portion and the outer cylindrical surface, and wherein a rear portion of the trailing leg is directed away from the outer cylindrical surface.

16. A variable-head impeller assembly for a waste pulping apparatus for use in any of a plurality of expected downstream head conditions, comprising:

a sieve ring having axially opposed first and second ends, an inner cylindrical surface and an outer cylindrical surface;

a rotating blade for pulping waste, the rotating blade having an axis of rotation, a base and a plurality of ears that axially extend away from the base;

wherein the sieve ring encircles the base at the first end and at least a portion of the ears are radially spaced inside the inner cylindrical surface so that the ears rotate within the sieve ring;

a plurality of first pumping vanes providing a predetermined flow rate against a first predetermined head;

a plurality of second pumping vanes providing the predetermined flow rate against a second predetermined head;

wherein one of the pluralities of pumping vanes is selected in order to best match predetermined head with expected downstream head conditions to provide the predetermined flow rate; and

wherein each pumping vane in the selected one of the pluralities has a pumping surface that rotates radially outside of the outer cylindrical surface of the sieve ring.

17. A variable-head impeller assembly according to claim 16, wherein each pumping vane has a leading leg, a middle leg and a trailing leg, wherein a rear portion of the middle leg is directed to the outer cylindrical surface of the sieve ring so that there is a predetermined clearance between the rear portion and the outer cylindrical surface, and wherein a rear portion of the trailing leg is directed away from the outer cylindrical surface.

18. A variable-head impeller assembly according to claim 16, further comprising a stationary blade adjacent to the inner cylindrical surface at the second end of the sieve ring, wherein the stationary blade is in close proximity to the ears of the rotating blade.

19. A variable-head impeller assembly according to claim 16, wherein the selected one of the pluralities of pumping vanes provides a predetermined combined flow rate of about 90 to about 120 gallons per minute.

20. An impeller assembly for a waste pulping apparatus comprising:

a sieve ring having axially opposed first and second ends, an inner cylindrical surface and an outer cylindrical surface;

a rotating blade for pulping waste, the rotating blade having an axis of rotation, a base and a plurality of ears that axially extend away from the base;

wherein the sieve ring encircles the base at the first end and at least a portion of the ears are radially spaced inside the inner cylindrical surface so that the ears rotate within the sieve ring;

means for rotating the rotating blade;

a plurality of pumping vanes for pumping the slurry, each pumping vane having a leading leg connected to the means for rotating the rotating blade and a trailing leg connected to the leading leg;

wherein the leading leg is connected to the means for rotating the rotating blade so that the leading and trailing legs are radially outside of the outer cylindrical surface of the sieve ring;

wherein a rear portion of the leading leg is directed toward the outer cylindrical surface of the sieve ring so that there is a predetermined clearance between the rear portion of the middle leg and the outer cylindrical surface; and

wherein a rear portion of the trailing leg is angled away from the outer cylindrical surface of the sieve ring.

21. An impeller assembly according to claim 20, wherein the rear portion of the leading leg and the trailing leg are generally planar.

22. An impeller assembly according to claim 20, wherein a second portion of the leading leg is generally parallel to a plane that is tangent to the outside surface of the sieve ring.

23. An impeller assembly according to claim 22, wherein the second portion is generally planar.

24. An impeller assembly according to claim 20, further comprising a stationary blade adjacent to the inner cylindrical surface of the sieve ring and in close proximity to the rotating blade.

25. An impeller assembly according to claim 20, wherein the sieve ring includes sizing holes, and wherein the sizing holes have a diameter of between about 1.3 cm and about 1.9 cm.