Method for handling a slag pot or ladle and pyrometallurgical tools

Patent metadata

Field	Value
Publication number	US-11221181-B2
Application number	US-201716467161-A
Country	US
Kind code	B2
Filing date	Dec 7, 2017
Priority date	Dec 8, 2016
Publication date	Jan 11, 2022
Grant date	Jan 11, 2022

Abstract

A method is shown for handling a slag pot or ladle and pyrometallurgical tools made form steel or cast iron, comprising the steps of spraying a mineral suspension onto a wall and bringing said slag pot or ladle or the pyrometallurgical tool into service, wherein said mineral suspension comprises calcic particles in suspension in an aqueous phase forming a calcic particle milk having a calcic particle content of between 20% and 60% by weight with respect to the weight of said calcic particle milk, said mineral layer being a fine layer.

First claim

The invention claimed is:

1. A method for handling a slag pot or ladle being a steel or cast-iron pot or ladle comprising an internal wall and an external wall, said method comprising the steps of:
a) spraying a mineral suspension on said internal wall, the temperature of said slag pot or ladle being greater than 100° C., so as to line said internal wall with a mineral layer, prior to the steps of:
b) collecting slag in said slag pot or ladle, lined on its internal wall with said mineral layer, of a pyrometallurgic tool,
c) transporting said slag pot or ladle from said pyrometallurgic tool to a slag deposition site,
d) emptying said slag pot or ladle at said slag-deposition site in order to eliminate the slag contained in said pot or ladle,
e) wherein step a) is performed with the purpose of bringing said slag pot or ladle lined with said mineral layer into service in order to repeat steps b) to d), and
wherein said mineral suspension comprises calcic particles in suspension in an aqueous phase forming a calcic-particle milk, said calcic particles being chosen from the group consisting of slaked lime, at least partially slaked decarbonated dolomite, limestone and mixtures thereof, the at least partially slaked decarbonated dolomite being obtained from decarbonated dolomite, the decarbonated dolomite having a quick part caused by the release of CO 2 during cooking, the at least partially slaked decarbonated dolomite being obtained by adding water in order to hydrate the quick part of the decarbonated dolomite, the mineral suspension having a calcic particle content of between 20% and 60% by weight with respect to the weight of said calcic-particle milk, said calcic particles in the calcic particle milk of said mineral suspension having a mean particle size d 50 of between 1.5 μm and 10 μm and wherein said mineral layer is a fine layer coated on the internal wall, the layer having a layer thickness of between 0.1 and 0.5 mm, in which said mineral suspension further comprises additives, selected from the group consisting of carbohydrates, dispersants and fluidifying additives and wherein said dispersants and fluidifying additives are selected from the group consisting of polycarbonates, polyacrylates and polyphosphonates.

2. The method of claim 1 , in which said additive is selected from the group consisting of sucrose, saccharose, sorbitol, xylose, glucose, galactose, fructose, mannose, lactose, maltose, glucuronic acid, gluconic acid, erythritol, xylitol, lactitol, maltitol, dextrins, cyclodextrins, inulin, glucitol, uronic acid, rhamnose, arabinose, erythrose, threose, ribose, allose, trehalose, galacturonic acid, and mixtures thereof.

3. The method of claim 2 , in which said additive is selected from the group consisting of sucrose, saccharose, sorbitol and mixtures thereof.

4. The method of claim 1 , in which said calcic particle milk has a viscosity of between 0.1 Pa·s and 2 Pa·s.

5. The method of claim 1 , in which said calcic particles of the calcic particle milk have a particle size d 97 of between 7 and 100 μm.

6. The method of claim 1 , in which said calcic particle milk is a milk-of lime and said calcic particles are slaked lime particles, and in which said milk-of-lime has a reactivity expressed in the form of a dissolution time t(90%) greater than 0.1 seconds and less than 10 seconds.

7. The method of claim 1 , in which said calcic particle milk has a calcic particle content greater than or equal to 25% by weight with respect to the total weight of the calcic particle milk, and a calcic particle content of less than or equal to 55% by weight with respect to the total weight of the calcic particle milk.

8. A method for lining an internal wall of a slag pot or ladle made from steel or cast iron with a mineral layer of calcic particle milk using a milk, wherein the milk of calcic particles is selected from the group consisting of slaked lime, at least partially slaked decarbonated dolomite, limestone and mixtures thereof, the at least partially slaked decarbonated dolomite being obtained from decarbonated dolomite, the decarbonated dolomite having a quick part caused by the release of CO 2 during cooking, the at least partially slaked decarbonated dolomite being obtained by adding water in order to hydrate the quick part of the decarbonated dolomite, in which said calcic particle milk is sprayed to form a fine mineral layer of calcic particles and has a calcic particle content of between 20% and 60% by weight with respect to the total weight of the calcic particle milk, said fine mineral layer of calcic particles having a layer thickness of between 0.1 and 0.5 mm and said calcic particles of said mineral suspension having a mean particle size d 50 of between 1.5 μm and 10 μm.

9. The method of claim 8 , in which said mineral suspension further comprises an additive selected from the group consisting of carbohydrates, dispersants and fluidifying additives, and wherein said dispersants and fluidifying additives are selected from the group consisting of polycarbonates, polyacrylates, and polyphosphonates.

10. The method of claim 9 , in which said additive is selected from the group consisting of sucrose, saccharose, sorbitol, xylose, glucose, galactose, fructose, mannose, lactose, maltose, glucuronic acid, gluconic acid, erythritol, xylitol, lactitol, maltitol, dextrins, cyclodextrins, inulin, glucitol, uronic acid, rhamnose, arabinose, erythrose, threose, ribose, allose, trehalose, galacturonic acid, and mixtures thereof.

11. The method of claim 9 , in which said additives are selected from the group consisting of sucrose, saccharose, sorbitol and mixtures thereof.

12. The method of claim 8 , in which said calcic particle milk has a viscosity of between 0.1 Pa·s and 2 Pa·s.

13. The method of claim 8 , in which said calcic particles of the calcic particle milk have a particle size d 97 of between 7 and 100 μm.

14. The method of claim 8 , in which said calcic particle milk has a calcic particle content greater than or equal to 25% by weight with respect to the total weight of the calcic particle milk, and a calcic particle content of less than or equal to 55% by weight with respect to the total weight of the calcic particle milk.

Assignees

• Lhoist Rech Et Developpement Sa

Inventors

• Denollin Guillaume

Classifications

• C21B3/10 Primary

  Slag pots; Slag cars · CPC title

• F27D3/1545 Primary

  Equipment for removing or retaining slag · CPC title

• F27D1/1636

  Repairing linings by projecting or spraying refractory materials on the lining · CPC title