Hybrid fluidized bed and pulverized coal combustion system and a process utilizing said system

Patent 4993332 Issued on February 19, 1991. Estimated Expiration Date:

September 13, 2009. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.

Abstract Claims Description Full Text

Patent References

Circulating fluidized bed boiler
Patent #: 4267801
Issued on: 05/19/1981
Inventor: Robinson

Disposal of waste products by combustion
Patent #: 4270468
Issued on: 06/02/1981
Inventor: Robinson , et al.

Coal beneficiation/combustion system
Patent #: 4397248
Issued on: 08/09/1983
Inventor: Mehta , et al.

Plant for the combustion of impure solid fuel
Patent #: 4421036
Issued on: 12/20/1983
Inventor: Brannstrom , et al.

System and method for firing coal having a significant mineral content
Patent #: 4438709
Issued on: 03/27/1984
Inventor: Borio , et al.

Method of controlling combustion Patent #: 4528918
Issued on: 07/16/1985
Inventor: Sato , et al.

Inventors

Assignee

Application

No. 416312 filed on 09/13/1989

US Classes:

110/347, Burning pulverized fuel110/204, Recirculation means110/232, Means for pulverizing solid fuel110/245, Fluidized bed of noncombustible particles110/263UTILIZING POWDERED FUEL

Examiners

Primary: Favors, Edward G.

Attorney, Agent or Firm

Dubno; Herbert

Foreign Patent References

2105606 GB. 03/25/1983

International Class

F23D 001/00

Foreign Application Priority Data

1987-11-17 HU

Abstract

A hybrid combustion system is provided combining advantages of a fluidized bed combustion portion and a pulverized coal combustion portion. The former portion includes a fluidized bed chamber, a coal mill without an air separator, a recycling duct connected to the coal mill, a coal supply duct, and a spray feeder. The fluidized coal combustion portion includes a pulverizing coal mill with air separator, a blowing duct for blowing ground coal, at least one pulverized coal burner and an air recycling duct for recycling combustion air. Fluidized bed combustion takes place in a lower part of the system and pulverized coal combustion takes place above the fluidized bed combustion. Each of the portions may be independently operated of the other. A main combustion chamber is common to both the fluidized bed portion and the pulverized coal portion. A related process is also described.