Method for stabilizing slag by using a combustion device

Abstract

This invention provides a method for stabilizing furnace slag using a combustion device. The method utilizes a combustion device for combustion (i.e., preparation and combustion steps). When the combustion device generates high-temperature combustion exhaust gas containing carbon dioxide, this exhaust gas reacts with the furnace slag containing free calcium oxide (CaO) (i.e., stabilization step). This involves the free calcium oxide in the furnace slag reacting with the carbon dioxide in the combustion exhaust gas, effectively capturing the carbon dioxide in the combustion exhaust gas. Simultaneously, a calcium carbonate coating forms on the surface of the furnace slag. This allows for rapid and low-cost stabilization of the furnace slag, enabling resource reuse of the stabilized slag.

Claims

1. A method for stabilizing slag using a combustion device, comprising: a preparation step, wherein a combustion device is provided, the combustion device comprising a furnace body having a combustion chamber, a heater disposed in the combustion chamber, a feed inlet connected to the combustion chamber for fuel entry, an air inlet connected to the combustion chamber for gas entry, and an exhaust port connected to the combustion chamber for exhaust of combustion exhaust gas, wherein, The combustion chamber is equipped with an air distribution plate with a plurality of holes, and the air distribution plate is also equipped with slag containing free calcium oxide (CaO). The combustion process includes a combustion step in which the gas is first introduced into the combustion chamber through the air inlet and passes through the holes of the air distribution plate to blow the slag, thereby suspending the slag in the combustion chamber. At this time, the slag is preheated by the heater, and the fuel is introduced into the combustion chamber through the feed inlet to mix the fuel with the slag and start combustion, producing combustion exhaust gas containing carbon dioxide during the combustion process. The process also includes a stabilization step in which, under the high temperature conditions in the combustion chamber, the carbon dioxide contained in the combustion exhaust gas reacts directly with the free calcium oxide contained in the slag to produce a carbonation reaction. In addition to effectively capturing the carbon dioxide contained in the combustion exhaust gas, a calcium carbonate coating is formed on the surface of the slag to remove the free calcium oxide contained in the slag, thereby completing the stabilization process of the slag.

2. The method for stabilizing slag using a combustion device as described in claim 1, wherein, The stabilization step is followed by a carbon capture step, in which a carbon capture device is installed in the combustion chamber and near the exhaust port. The carbon capture device has at least one mesh plate with a plurality of openings and the slag is provided on the mesh plate to perform carbon capture operation on the combustion exhaust gas.

3. A method for stabilizing slag using a combustion device, comprising: a preparation step, wherein a combustion device and a carbon-catching device are provided, the combustion device comprising a furnace body having a combustion chamber, a feed inlet connected to the combustion chamber for fuel entry, and an exhaust port connected to the combustion chamber for exhaust of combustion exhaust gas, and the carbon-catching device having at least one screen plate having a plurality of mesh openings, and slag containing free calcium oxide (CaO) disposed on the screen plate; The combustion process includes a combustion step in which the fuel is fed through the feed inlet and combusted, producing combustion exhaust gas containing carbon dioxide. A stabilization step involves introducing the combustion exhaust gas into the carbon capture device, allowing it to pass through the mesh of the screen and interact with the slag. Under high temperatures within the combustion chamber, the carbon dioxide in the combustion exhaust gas reacts directly with the free calcium oxide in the slag to form a carbonation reaction. This effectively captures the carbon dioxide in the combustion exhaust gas and simultaneously forms a calcium carbonate coating on the surface of the slag, removing the free calcium oxide and thus stabilizing the slag.

4. The method for stabilizing slag using a combustion device as described in claim 3, wherein, The carbon capture device is located in the combustion chamber of the combustion device.

5. The method for stabilizing slag using a combustion device as described in claim 3, wherein, The carbon capture device is connected to the exhaust port of the combustion device.

6. A method for stabilizing slag using a combustion device as described in claims 1, 2, 3, 4, or 5, wherein, These slags are reduction slags.

7. A method for stabilizing slag using a combustion device as described in claims 1, 2, 3, 4, or 5, wherein, These slags are oxide slags.

8. A method for stabilizing slag using a combustion device as described in claims 1, 2, 3, 4, or 5, wherein... The particle size of these slags is less than 500 mm.

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