Gasifier ash processing subsystem

• US 8,591,608 B2
• Filed: 09/29/2009
• Issued: 11/26/2013
• Est. Priority Date: 09/29/2009
• Status: Active Grant

• Current Assignee: MSW Power Coporation
• Original Assignee: MSW Power Coporation
• Inventors: Young, Matthew, Anthony, Steven, Armstrong, Stephen, Chase, Steven
• Primary Examiner(s): Handal, Kaity V.
• Application Number:
  US12/586,830
• Publication Number:
  US 20110072722A1
• Time in Patent Office: 1,519 Days
• Field of Search: None
• US Class Current: 48/76
• CPC Class Codes: C10J 2300/0916 Biomass
• CPC Class Codes: C10J 2300/0956 Air or oxygen enriched air
• CPC Class Codes: C10J 2300/1625 with solids treatment
• CPC Class Codes: C10J 3/34 Grates; Mechanical ash-removing devices
• CPC Class Codes: C10J 3/36 Fixed grates
• CPC Class Codes: F23G 2207/102 for pressure
• CPC Class Codes: F23G 5/002 characterised by their grates F23G5/05 takes precedence
• CPC Class Codes: F23G 5/50 Control or safety arrangements
• CPC Class Codes: F23H 13/08 Grates specially adapted for gas generators and also applicable to furnaces

Abstract

A gasifier includes a combustion zone where a gas is introduced and fuel is combusted and at least one sensor for measuring a predetermined condition in the gasifier. A grate subsystem contains the fuel and includes at least one grinding mechanism. A controller is responsive to the at least one sensor and controls the grinding mechanism by activating the grinding mechanism if the predetermined condition exists to reduce the collection of non-fuel products on the grate subsystem.

Claims

1. A gasifier comprising:

a combustion zone where a gas is introduced and fuel is combusted;

at least one sensor for measuring a predetermined condition in the gasifier;

a grate subsystem for containing the fuel, the grate subsystem

including at least one grinding mechanism between downwardly angled grates defining a hopper; and

a controller, responsive to the at least one sensor, for controlling

the grinding mechanism, the controller configured to;

control the grinding mechanism if the predetermined

condition exists to reduce the collection of non-fuel products on the grate subsystem.

2. The gasifier of claim 1 in which the sensor is a pressure sensor.

3. The gasifier of claim 2 in which the pressure sensor is responsive to the pressure below the grate subsystem.

4. The gasifier of claim 2 in which the controller is programmed to:

determine if a pressure output by the pressure sensor meets or

exceeds a predetermined pressure,

activate the grinding mechanism if the pressure meets or exceeds

the predetermined pressure, and

deactivate the grinding mechanism if the pressure does not meet or

exceed the predetermined pressure.

5. The gasifier of claim 4 in which the controller is further programmed to activate the grinding mechanism for increasing time intervals until the pressure does not meet or exceed the predetermined pressure.

6. The gasifier of claim 1 in which the grinding mechanism includes at least two spaced grinding shafts disposed in the hopper area.

7. The gasifier of claim 6 in which each shaft includes a gear meshed with a gear on the other shaft to drive the shafts together.

8. The gasifier of claim 7 in which the grate subsystem further includes a motor for driving a said shaft.

9. The gasifier of claim 8 in which the controller is configured to energize the motor.

10. The gasifier of claim 6 in which each grate includes slots between 0.1 and 0.3 inches wide spaced between 0.5 and 0.8 inches apart and there is a gap of between 0.1 and 0.3 inches between the grinding shafts.

11. The gasifier of claim 6 in which the grate subsystem further includes a housing configured as a tray containing the grates and the grinding shafts.

12. The gasifier of claim 11 in which the tray includes spaced side members connected by spaced end members.

13. The gasifier of claim 12 in which the grinding shafts extend between the spaced end members.

14. The gasifier of claim 13 further including bearings on each shaft rotatably coupling the shafts to said end members.

15. The gasifier of claim 1 in which the grate subsystem includes two pairs of fixed downwardly angled grates defining two hopper areas.

16. The gasifier of claim 15 in which the grinding mechanism includes two pairs of spaced grinding shafts, one pair disposed in each hopper area.

17. A gasifier grate subsystem comprising:

at least two downwardly angled fixed grates defining a hopper area

between the grates;

at least two spaced grinding shafts disposed in the hopper area; and

a controller, responsive to a sensor, configured to control

the grinding shafts if a predetermined condition exists to reduce the collection of non-fuel products on the fixed grates.

18. The gasifier grate subsystem of claim 17 in which each shaft includes a gear meshed with a gear on the other shaft to drive the shafts together.

19. The gasifier grate subsystem of claim 18 in which the grate subsystem further includes a motor for driving a said shaft.

20. The gasifier grate subsystem of claim 18 in which the controller is configured to energize the motor.

21. The gasifier grate subsystem of claim 17 in which the grate subsystem includes two pairs of fixed downwardly angled grates defining two hopper areas.

22. The gasifier grate subsystem of claim 21 in which there are two pairs of spaced grinding shafts, one pair disclosed in each hopper area.

23. The gasifier grate subsystem of claim 17 in which each grate includes slots between 0.1 and 0.3 inches wide spaced between 0.5 and o.s inches

apart and there is a gap of between 0.1 and 0.3 inches between the grinding shafts.

24. The gasifier grate subsystem of claim 17 further including a housing configured as a tray containing the grates and the grinding shafts.

25. The gasifier grate subsystem of claim 24 in which the tray includes spaced side members connected by spaced end members.

26. The gasifier grate subsystem of claim 25 in which the grinding shafts extend between the spaced end members.

27. The gasifier grate subsystem of claim 26 further including bearings on each shaft rotatably coupling the shafts to said end members.

28. A gasifier grate control system comprising:

a grate subsystem for containing fuel in a gasifier, the grate

subsystem including at least one grinding mechanism between downwardly angled grates defining a hopper area; and

a controller, responsive to at least one sensor, for controlling the

grinding mechanism, the controller configured to actuate the grinding mechanism if a predetermined condition exists to reduce the collection of non-fuel products on the grate subsystem.

29. The gasifier grate control system of claim 28 in which the sensor is a pressure sensor.

30. The gasifier grate control system of claim 29 in which the pressure sensor is responsive to the pressure below the grate subsystem.

31. The gasifier grate control system of claim 28 in which the grinding mechanism includes at least two spaced grinding shafts disposed in the hopper area.

32. The gasifier grate control system of claim 31 in which the grate subsystem further includes a housing configured as a tray containing the grates and the grinding shafts.

33. The gasifier grate control system of claim 32 in which the tray includes spaced side members connected by spaced end members.

34. The gasifier grate control system of claim 33 in which the grinding shafts extend between the spaced end members.

35. The gasifier grate control system of claim 28 in which the controller is programmed to:

determine if the sensor output meets or exceeds the predetermined condition,

activate the grinding mechanism if the sensor output meets or

exceeds the predetermined condition, and

deactivate the grinding mechanism if the sensor output does not

meet or exceed the predetermined condition.

36. The gasifier grate control system of claim 35 in which the controller is further programmed to activate the grinding mechanism for increasing time intervals until the sensor output does not meet or exceed the predetermined condition.

37. A gasifier comprising:

combusted;

a combustion zone where a gas is introduced and fuel is

a grate subsystem for containing the fuel

including downwardly angled grates defining a hopper area and including at least one grinding shaft proximate the hopper area; and

a controller configured to control the grinding shaft.

38. A gasifier grate control system comprising:

a grate subsystem for containing fuel in a gasifier, the grate

subsystem including downwardly angled grates defining a hopper area and at least one grinding mechanism proximate the hopper area; and

a controller for controlling the grinding mechanism.

39. A gasifier grate control system comprising:

a grate subsystem for containing fuel in a gasifier, the grate

subsystem including downwardly angled grates defining a hopper and at least two grinding shafts disposed below the hopper; and

a controller for controlling the grinding shafts.