Thermal treatment of mineral materials in a reducing atmosphere using alternative fuels

Patent metadata

Field	Value
Publication number	US-2022316800-A1
Application number	US-202017632139-A
Country	US
Kind code	A1
Filing date	Jul 28, 2020
Priority date	Aug 2, 2019
Publication date	Oct 6, 2022
Grant date	—

Abstract

An apparatus for thermal treatment of mineral materials may include a first combustion chamber, a second combustion chamber, and a reactor for the thermal treatment of mineral materials. The first combustion chamber is configured for burning a first fuel fed by a first fuel feed device, and the first combustion chamber and the second combustion chamber are connected via a first conduit for transferring hot gases from the first combustion chamber into the second combustion chamber. The second combustion chamber is configured for burning a second fuel that is different than the first fuel and is fed by a second fuel feed device. The second combustion chamber and the reactor are connected via a second conduit for transferring hot gases from the second combustion chamber into the reactor. The reactor has a third feed conduit for introducing a third fuel.

First claim

1 .- 10 . (canceled)

11 . An apparatus for thermal treatment of mineral materials, the apparatus comprising:
a first combustion chamber configured to burn a first fuel, with the first combustion chamber comprising a first fuel feed device for introducing the first fuel; a second combustion chamber configured to burn a second fuel that is different than the first fuel, the second combustion chamber being connected to the first combustion chamber via a first conduit for transferring hot gasses from the first combustion chamber into the second combustion chamber, wherein the second combustion chamber comprises a second fuel feed device for introducing the second fuel; and a reactor for thermal treatment of mineral materials, wherein the second combustion chamber and the reactor are connected via a second conduit for transferring hot gases from the second combustion chamber into the reactor, wherein the reactor has a third fuel feed conduit for introducing a third fuel.

12 . The apparatus of claim 11 wherein the first fuel is coal, coal dust, oil, natural gas, biogas, methane, ethane, propane, butane, or hydrogen, wherein the second fuel is a substitute fuel.

13 . The apparatus of claim 11 wherein the first combustion chamber includes a first oxygen feed device, wherein the second combustion chamber includes a second oxygen feed device, wherein at least one of the second combustion chamber, the second conduit, or the reactor includes a sensor for measuring oxygen content.

14 . The apparatus of claim 11 wherein the second combustion chamber is configured to burn the second fuel on a grate.

15 . The apparatus of claim 11 wherein the reactor is a calciner.

16 . The apparatus of claim 11 wherein the reactor is an entrained-flow calciner.

17 . The apparatus of claim 11 wherein the reactor is a rotary tube furnace.

18 . A process for thermally treating mineral materials, the process comprising:
combusting a first fuel in a first combustion chamber; transferring hot gasses from the first combustion chamber into a second combustion chamber; combusting a second fuel in the second combustion chamber; transferring hot gasses from the second combustion chamber into a reactor; and substoichiometrically combusting a third fuel in the reactor and thermally treating mineral materials.

19 . The process of claim 18 comprising regulating introduction of the third fuel for substoichiometric combustion based on a color of the thermally treated mineral materials after removal from the reactor.

20 . The process of claim 18 comprising regulating introduction of the third fuel for substoichiometric combustion based on a measured parameter, wherein the measured parameter is oxygen content in the second combustion chamber, oxygen content in a connection between the second combustion chamber and the reactor, oxygen content in the reactor, or a property of a product of the thermally treated mineral materials after removal from the reactor.

21 . The process of claim 18 wherein thermally treating the mineral materials is performed at an oxygen partial pressure pO 2 of less than 10 −8 bar.

22 . The process of claim 18 wherein thermally treating the mineral materials is performed at an oxygen partial pressure pO 2 of less than 10 −11 bar.

23 . The process of claim 18 wherein thermally treating the mineral materials is performed at a volume ratio of CO 2 /CO of less than 1000.

24 . The process of claim 18 wherein thermally treating the mineral materials is performed at a volume ratio of CO 2 /CO of less than 50.

25 . The process of claim 18 wherein thermally treating the mineral materials is performed at an air index of less than 1.

26 . The process of claim 18 wherein thermally treating the mineral materials is performed at an air index of between 0.70 and 0.99.

27 . The process of claim 18 wherein thermally treating the mineral materials is performed at an air index of between 0.85 and 0.98.

Assignees

• Thyssenkrupp Ind Solutions Ag
• Thyssenkrupp Ag

Inventors

• Lemke Jost
• Veckenstedt Ines
• Grund Guido
• Koslowski Lutz
• Brinkmann Christian

Classifications

• F23G2209/26

  Biowaste · CPC title

• F23G7/10

  of field or garden waste {or biomasses} · CPC title

• C04B7/45

  in fluidised beds {, e.g. spouted beds} · CPC title

• C04B7/4446

  the fuel being treated in a separate gasifying or decomposing chamber, e.g. a separate combustion chamber · CPC title

• B01J6/002

  using rotating drums · CPC title