Calcium Sulfate Looping Cycles for Sour Gas Combustion and Electricity Production

Patent metadata

Field	Value
Publication number	US-2016017799-A1
Application number	US-201414334077-A
Country	US
Kind code	A1
Filing date	Jul 17, 2014
Priority date	Jul 17, 2014
Publication date	Jan 21, 2016
Grant date	—

Abstract

A calcium looping combustion process for sour gas combustion comprising a system that includes several reaction zones. The system is configured to provide oxygen transfer media production, generation of a syngas product stream, and in-situ H 2 S removal from the sour gas. The system is also configured such that the calcium-based transfer media and the calcium-based oxygen carrier are reproduced via reactions in another reaction zone, and recirculated in the system.

First claim

What is claimed is:

1 . A process for in-situ removal of sulfur, oxygen transfer media production, and sour gas combustion using calcium looping combustion while producing a product stream, comprising the steps of:
calcining CaCO 3 in an air reactor to produce a calcium-based transfer media; transferring the calcium-based transfer media from the air reactor to a fuel reactor; delivering sour gas into the fuel reactor; reducing the calcium-based transfer media disposed within the fuel reactor to provide gas-phase oxygen; oxidizing the reduced calcium-based transfer media with air in the air reactor to produce a calcium-based oxygen transfer media; delivering the calcium-based oxygen transfer media from the air reactor to a riser; transferring the clean sour gas (without H 2 S) from the fuel reactor to the riser; combusting the sour gas within the riser to produce the product stream which includes the reduced calcium-based transfer media; removing the reduced calcium-based transfer media from the product stream; re-oxidizing the reduced calcium-based transfer media with air in the air reactor to produce the calcium-based oxygen transfer media; and delivering the calcium-based oxygen transfer media back to the riser.

2 . The process of claim 1 , wherein the calcium-based transfer media comprises a bed that is disposed on a perforated substrate that is disposed in a lower portion of the fuel reactor.

3 . The process of claim 2 , wherein the bed is fluidized by a stream of CO 2 , steam, or depleted air from the air reactor or a combination thereof.

4 . The process of claim 3 , wherein the depleted air contains 2 to 5% of O 2 .

5 . The process of claim 1 , wherein the calcium-based transfer media is CaO.

6 . The process of claim 1 , wherein the reduced calcium-based transfer media is CaS.

7 . The process of claim 1 , wherein the calcium-based oxygen transfer media reacts with the sour gas in the riser, producing the reduced calcium-based transfer media.

8 . The process of claim 1 , wherein the sour gas is a feed that flows into an inlet formed in the bottom of the fuel reactor such that the H 2 S present in the sour gas reacts with the calcium-based transfer media.

9 . The process of claim 1 , wherein CaSO 4 is the calcium-based oxygen transfer media.

10 . The process of claim 1 , wherein the calcium-based oxygen transfer media reacts with the methane present in the sour gas in the riser, producing the product stream.

11 . The process of claim 10 , wherein the product stream comprises CO and H 2 .

12 . The process of claim 11 , wherein the product stream comprises syngas.

13 . The process of claim 1 , wherein the reduced calcium-based transfer media is removed from the product stream using a gas-solid separation device.

14 . The process of claim 13 , wherein the gas-solid separation device is a cyclone.

15 . The process of claim 13 , wherein the step of removing the reduced calcium-based transfer media from the product stream further comprises the step of delivering the reduced calcium-based transfer media to a hopper, injecting air into the hopper to oxidize the reduce calcium-based transfer media to produce the calcium-based oxygen transfer media, which is delivered to the riser.

16 . The process of claim 9 , wherein a ratio of Ca/S is between about 1.2 and 2.5.

17 . The process of claim 1 , wherein heat and steam are generated as products.

18 . The process of claim 1 , wherein gypsum is generated as a byproduct.

19 . The process of claim 1 , wherein a portion of the calcium-based transfer media produced by the calcination step is delivered to the riser to react with the H 2 S present in the sour gas.

20 . A process for in-situ removal of sulfur, oxygen transfer media production, and sour gas combustion using calcium looping combustion while producing a product stream, comprising the steps of:
calcining CaCO 3 in an air reactor to produce a calcium-based transfer media; transferring the calcium-based transfer media from the air reactor to a fuel reactor; delivering sour gas into the fuel reactor such that the sour gas reacts with the calcium-based transfer media and the calcium-based transfer media is reduced; and injecting a calcium-based oxygen transfer media into a riser that is in fluid communication with the fuel reactor, whereby the sour gas is combusted within the riser to produce the product stream which includes the reduced calcium-based transfer media; wherein the step of injecting the calcium-based oxygen transfer media comprises the step of oxidizing the reduced calcium-based transfer media with air in the air reactor to produce the calcium-based oxygen transfer media which is then delivered to the riser.

21 . The process of claim 20 , further including the step of injecting into the riser the calcium-based transfer media which was produced by the step of calcining the CaCO 3 in the air reactor.

22 . The process of claim 20 , wherein the calcium-based transfer media comprises CaO; the reduced calcium-based transfer media comprises CaS and the calcium-based oxygen transfer media comprises CaSO 4 .

23 . The process of claim 21 , wherein the calcium-based transfer media comprises CaO; the reduced calcium-based transfer media comprises CaS and the calcium-based oxygen transfer media comprises CaSO 4 , and wherein at least a portion of both the CaO and the CaSO 4 formed in the air reactor are delivered together to both the fuel reactor and the riser.

24 . The process of claim 23 , wherein the CaSO 4 reacts with methane in the sour gas within the fuel reactor and the riser by providing its oxygen.

25 . The process of claim 22 , further including the step of removing SO 2 from a product stream of the air reactor by reacting the SO 2 with a calcium-based sorbent that is injected into the air reactor and reacts with the SO 2 to produce CaSO 4 which is separated from the product stream of the air reactor.

26 . A process for in-situ removal of sulfur, calcium-based oxygen transfer media production, and sour gas combustion using calcium looping combustion while producing a product stream of syngas, comprising the steps of:
calcining CaCO 3 in an air reactor to produce a calcium-based transfer media; transferring the calcium-based transfer media from the air reactor to a fuel reactor; delivering sour gas into the fuel reactor; reducing the calcium-based transfer media disposed within the fuel reactor; delivering the reduced calcium-based transfer media from the fuel reactor to the air reactor; oxidizing the reduced calcium-based transfer media with air in the air reactor to produce a calcium-based oxygen transfer media; delivering the calcium-based oxygen transfer media from the air reactor to a riser; transferring the sour gas from the fuel reactor to the riser; combusting the sour gas within the riser to produce the syngas product stream which includes the reduced calcium-based transfer media; removing the reduced calcium-based transfer media from the product stream; re-oxidizing the reduced calcium-based transfer media with air in the air reactor to produce the calcium-based oxygen transfer media; and delivering the calcium-based oxygen transfer media back to the riser.

27 . The process of claim 26 , wherein the syngas produced in the riser is used in a combined cycle turbine to pr

Assignees

• Saudi Arabian Oil Co

Inventors

• Hoteit Ali
• Younes Mourad

Classifications

• F23C10/08 Primary

  characterised by the arrangement of separation apparatus, e.g. cyclones, for separating particles from the flue gases · CPC title

• Y02E20/16

  Combined cycle power plant [CCPP], or combined cycle gas turbine [CCGT] · CPC title

• C01B2203/0255

  containing a non-catalytic partial oxidation step · CPC title

• C01B3/36 Primary

  using oxygen; using mixtures containing oxygen as gasifying agents · CPC title

• F23C2900/99008

  Unmixed combustion, i.e. without direct mixing of oxygen gas and fuel, but using the oxygen from a metal oxide, e.g. FeO · CPC title