Methods for operating a furnace

• US 10,641,482 B2
• Filed: 08/24/2015
• Issued: 05/05/2020
• Est. Priority Date: 10/27/2008
• Status: Active Grant

• Current Assignee: Imerys USA Incorporated (Parjointco N.V.)
• Original Assignee: Imerys USA Incorporated (Parjointco N.V.)
• Inventors: Leach, Billie, Landon, Thomas
• Primary Examiner(s): McAllister, Steven B
• Assistant Examiner(s): Bargero, John E
• Application Number:
  US14/833,294
• Publication Number:
  US 20150362186A1
• Time in Patent Office: 1,716 Days
• Field of Search: None
• CPC Class Codes: C01P 2004/61 Micrometer sized, i.e. from 1-100 micrometer
• CPC Class Codes: C01P 2004/62 Submicrometer sized, i.e. from 0.1-1 micrometer
• CPC Class Codes: C01P 2006/80 Compositional purity
• CPC Class Codes: C09C 1/402 Satin white, modifications thereof, e.g. carbonated or silicated; Calcium sulfoaluminates; Mixtures thereof, e.g. with calcium carbonate or kaolin
• CPC Class Codes: F23C 10/00 Fluidised bed combustion apparatus
• CPC Class Codes: F23C 10/01 in a fluidised bed of catalytic particles
• CPC Class Codes: F23C 10/18 Details; Accessories
• CPC Class Codes: F23C 10/28 Control devices specially adapted for fluidised bed, combustion apparatus
• CPC Class Codes: F23C 10/30 for controlling the level of the bed or the amount of material in the bed
• CPC Class Codes: F23C 2206/00 Fluidised bed combustion
• CPC Class Codes: F23G 2200/00 Waste incineration
• CPC Class Codes: F23G 2207/60 Additives supply
• CPC Class Codes: F23G 5/30 having a fluidised bed
• CPC Class Codes: F23J 7/00 Arrangement of devices for supplying chemicals to fire
• CPC Class Codes: F23J 9/00 Preventing premature solidification of molten combustion residues
• CPC Class Codes: F23K 2201/505 with additives

Abstract

A method for combusting fuel in the presence of an alkali-containing material may include introducing fuel into a furnace configured to combust the fuel. The method may also include introducing ball clay having a moisture content of at least about 5% by weight into the furnace, and heating at least a portion of the fuel and ball clay, such that at least a portion of the ball clay is at least partially calcined, and the at least partially calcined ball clay adsorbs at least a portion of alkali present in the furnace.

Claims

1. A method for combusting fuel in the presence of an alkali-containing material, the method comprising:

introducing fuel into a furnace configured to combust the fuel;

introducing ball clay comprising 20-80% kaolinite, 10-25% mica, and 6-65% quartz and having a moisture content of at least about 5% by weight into the furnace; and

heating at least a portion of the fuel and ball clay, such that at least a portion of the ball clay is at least partially calcined and the at least partially calcined ball clay adsorbs at least a portion of alkali present in the furnace.

2. The method of claim 1, wherein the ball clay has a moisture content ranging from about 5% by weight to about 15% by weight.

3. The method of claim 1, wherein the ball clay has a moisture content ranging from about 8% by weight to about 12% by weight.

4. The method of claim 1, wherein the ball clay comprises lump clay.

5. The method of claim 1, wherein the ball clay comprises clay that has been at least one of shredded and crushed.

6. The method of claim 1, wherein the ball clay comprises non-beneficiated ball clay.

7. The method of claim 1, wherein the ball clay has a BET surface area of at least about 9 m²/g.

8. The method of claim 1, wherein the ball clay has a BET surface area of at least about 15 m²/g.

9. The method of claim 1, wherein ball clay comprises clay derived from crude clay having a moisture content of at least about 15%.

10. The method of claim 1, further including introducing calcium carbonate into the furnace.

11. The method of claim 1, further comprising incorporating the furnace into a fluidized-bed reactor system.

12. The method of claim 11, wherein the fluidized-bed reactor system is a circulating fluidized-bed reactor system.

13. The method of claim 1, wherein the step of heating results in calcining at least a portion of the ball clay, and the method further comprises:

adsorbing at least a portion of alkali in the furnace via the calcined clay; and

removing at least a portion of the calcined clay and adsorbed alkali from the furnace.

14. The method of claim 1, wherein the fuel is coal, petroleum coke, or biofuel, or a combination of any of the foregoing.

15. The method of claim 1, wherein the ball clay comprises ball clay agglomerates having a size of no more than about 3 inches.

16. The method of claim 15, wherein the ball clay agglomerates have a size of no more than about 2 inches.

17. The method of claim 16, wherein the ball clay agglomerates have a size of no more than about 1 inch.

20. The method of claim 1, wherein the ball clay is added in an amount sufficient to maintain a boiler temperature in the range of about 930°

C. to about 1010°

C.

18. A method for combusting fuel in the presence of an alkali-containing material, the method comprising:

introducing fuel and calcium carbonate into a furnace configured to combust the fuel;

introducing ball clay into the furnace, the ball clay comprising 20-80% kaolinite, 10-25% mica, and 6-65% quartz and having a moisture content of at least about 5% by weight; and

heating at least a portion of the fuel, calcium carbonate, and ball clay, such that at least a portion of the ball clay is at least partially calcined and the at least partially calcined clay adsorbs at least a portion of alkali present in the furnace.

19. A method for operating a fluidized-bed reactor, the method comprising:

introducing an alkali-containing material into a fluidized-bed reactor;

introducing ball clay into the fluidized-bed reactor, the ball clay comprising 20-80% kaolinite, 10-25% mica, and 6-65% quartz and having a moisture content of at least about 5% by weight;

heating at least a portion of the alkali-containing material and ball clay, such that at least a portion of the ball clay is at least partially calcined and the at least partially calcined clay adsorbs at least a portion of alkali present in the fluidized-bed reactor; and

removing at least a portion of the at least partially calcined clay and adsorbed alkali from the fluidized-bed reactor.