Sulfur recovery from fluidized bed which heats gas in a closed circuit gas turbine

• US 3,913,315 A
• Filed: 01/10/1974
• Issued: 10/21/1975
• Est. Priority Date: 05/17/1971
• Status: Expired due to Term

• Current Assignee: Geoffrey Frederick Skinner
• Original Assignee: Geoffrey Frederick Skinner
• Inventors: Skinner, Geoffrey Frederick
• Primary Examiner(s): Freeh, William L.
• Assistant Examiner(s): Ross, Thomas I.
• Application Number:
  US05/432,278
• Time in Patent Office: 649 Days
• Field of Search: 60/39.18R,39.18A,39.18B,39.18C 122/4D
• US Class Current: 60/39.181
• CPC Class Codes: F02C 1/007 combination of cycles
• CPC Class Codes: F02C 1/05 characterised by the type or source of heat, e.g. using nuclear or solar energy
• CPC Class Codes: F02C 3/205 in a fluidised-bed combustor in combination with a steam cycle see F01K23/061; fluidised-bed apparatus in general B01J8/18; fluidised-bed combustors in general F23C10/00

Abstract

The invention described herein is a power plant in which energy is produced by means of a gas turbine driving, for example, an electric generator. The head for the gas turbine is produced by passing the compressed gas through tubes immersed in a fluidised bed burner, the heated gas then driving the turbine. In one preferred form of the invention the fluidised bed burner is fired with a sulfur contaminated fuel such as oil and the bed is constituted by particles, which will react with the sulfur. These sulfur-containing particles are then removed and the sulfur recovered by, for example, burning these particles to give SO2 gas which can be used in the preparation of sulfuric acid. In this way, polution of the atmosphere which occurs with conventional power plants fired with sulfur contaminated fuels can be avoided and the sulfur recovered and used.

Claims

1. A power plant comprising:

a fluidised bed burner;

means for firing said fluidised bed burner to operate at a given pressure;

tubes positioned so that they are immersed within said bed burner during operation of said burner;

a gas turbine, said gas turbine having a compressor of a capacity and operating pressure for compressing gas to be heated to a pressure within one atmosphere greater than said given pressure and an expansion turbine for expanding heated compressed gas and extracting energy therefrom;

a power generator driven by said gas turbine;

a conduit for passing compressed gas from said compressor to said tubes for heating said compressed gas; and

a conduit for passing said heated compressed gas from said tubes to said expansion turbine.

2. A power plant according to claim 1 further comprising a cooler and a heat exchanger, said compressor, said heat exchanger, said tubes, said expansion turbine and said cooler being in a closed loop so that gas passes from said compressor to said heat exchanger for preheating, to said tubes for heating, to said expansion turbine, to said heat exchanger to preheat said gas, to said cooler and back to said compressor.

3. Power plant according to claim 2 in which said gas circulating in said closed loop is helium.

4. Power plant according to claim 2 further comprising an emergency accumulator into which said gas in said closed loop can be vented in the event of a shut-down of said plant.

5. A power plant according to claim 2 further comprising a second compressor for compressing air, an air line connected with said compressor and said fluidised bed for feeding said compressed air to said fluidised bed;

a flue gas expansion turbine;

a flue gas line connecting said flue gas expansion turbine and said fluidised bed and a common shaft on which said compressor and expansion turbine of said gas turbine and said air compressor and flue gas expansion turbine are all mounted so that when said compressor and said expansion turbine of said turbine operate, said air compressor forces air through said air line into said fluidised bed and said flue gas expansion turbine is energized by flue gas.

6. Power plant according to claim 1 further comprising means for operating said fluidised bed burner at elevated pressures, said means including said compressor which compresses gas both for said gas turbine and for combustion in said fluidised bed burner, and a turbine for expanding and recovering energy from said combustion gases, the air expanded in said turbine of said gas turbine being passed back to said common compressor.

7. Power plant according to claim 6 wherein said common compressor, said turbines, and said power generator are all mounted on a common shaft.

8. Power plant according to claim 6 in which said gas turbine further comprises a heat exchanger and a cooler, said air from said common compressor passing to said heat exchanger for preheating, to said tube means for heating, to said expansion turbine, to said heat exchanger to preheat said compressed air, to said cooler and back to said common compressor.

9. Power plant according to claim 2 further comprising an exit turbine through which hot combustion gases pass for expansion before venting to the atmosphere, and a pre-compressor driven by said exit turbine to compress air for combustion in said burner.

10. Power plant according to claim 9 further comprising a burner, means for passing compressed air from said pre-compressor to said burner, and for passing combustion products from said burner to said exit turbine to assist control and start-up of said plant.

11. Power plant according to claim 1 in which said fluidised bed burner contains non-combustible fluidising particles capable of reacting with sulfur contaminants in fuel, means for removing sulfur containing particles from said burner and means for the recovering and use of said slufur.

12. Power plant according to claim 11 wherein said non-combustible particles are chosen from the group consisting of calcium oxide and magnesium oxide and said sulfur containing particles are calcium sulfide and magnesium sulfide respectively.

13. Power plant according to claim 11 further comprising means for burning said sulfur containing particles in air to give sulfur dioxide, and means for converting said sulfur dioxide to sulfuric acid.

14. Power plant according to claim 13 wherein said means for burning said sulfur containing particles is a fluidised bed.

15. Power plant according to claim 11 wherein said fluidised bed burner comprises:

an upper fluidised bed of non-combustible particles, a lower fluidised bed of non-combustible particles capable of reacting with sulfur, means for passing fluidising air in series to said lower bed and then to said upper bed, means for supplying sulfur contaiminated fuel to said lower bed for partial combustion and reaction of said sulfur with said particles, means for supplying further air to said upper bed to complete combustion of said fuel, said tube means being arranged within said upper bed, and recovering sulfur from said particles removed from said lower bed.