Method for granulating a metallurgical slag

Patent metadata

Field	Value
Publication number	US-12319983-B2
Application number	US-202117796951-A
Country	US
Kind code	B2
Filing date	Jan 28, 2021
Priority date	Feb 3, 2020
Publication date	Jun 3, 2025
Grant date	Jun 3, 2025

Abstract

A method for the granulation of a metallurgical slag includes blowing, from a blower or air nozzle, heated air onto liquid slag to atomize the liquid slag and subsequently form granulated slag as the atomized slag cools. The granulated slag is blown into and collected by a working chamber. In order to ensure a high quality of the granulated slag and operate in an energy-efficient manner, the atomization is provided by blowing a heated air jet free from the addition of water onto the liquid slag. The granulated slag particles are collected in the floor region of the working chamber. Air that is released from the working chamber is either supplied to a heat exchanger, which further heats the air jet blown onto the liquid slag, or the released air is directly recirculated to the blower or air nozzle in order to atomize the supply of liquid slag.

First claim

We claim:

1. A method for the granulation of a metallurgical slag, the method comprising:
blowing, from a blower, heated air onto a supply of liquid slag such that the liquid slag is transformed to atomized slag, wherein atomization is provided by blowing the heated air free of water onto the liquid slag;
directing the atomized slag into a single working chamber in which the atomized slag forms into granulated slag particles which are collected in a floor region of the single working chamber;
releasing, from the single working chamber, the heated air either to a heat exchanger, which further heats the released air and directs the further heated released air to an air inlet of the blower for blowing onto the liquid slag, or directly recirculating the released air from the single working chamber to the air inlet of the blower in order to atomize the liquid slag; and
wherein the supply of the liquid slag and the blowing of heated air from the blower onto the liquid slag occurs in a first section of the single working chamber and the granulated slag particles accumulate in a second section of the single working chamber, at a distance from the first section, wherein the released air from the single working chamber is removed from the single working chamber in a region of the first section, and wherein the first section and the second section of the single working chamber are separated from each other by a baffle plate located in a ceiling region of the single working chamber, wherein a portion of energy contained in the released air is used to supply a consumer.

2. The method according to claim 1 , wherein the liquid slag is kept free from water from the supply of slag and through formation and accumulation of granulated slag particles on the floor region of the single working chamber.

3. The method according to claim 1 , wherein the heated air used to blow onto the liquid slag is preheated to at least 60° C.

4. The method according to claim 1 , wherein the heated air, after having been used for the atomization of the liquid slag, has a temperature of at least 250° C.

5. The method according to claim 1 , wherein the consumer is a steam generator that is connected to a steam turbine/generator system for generating electrical energy.

6. The method according to claim 1 , wherein the further heated released air from the heat exchanger is blown onto the granulated slag particles from a secondary air inlet.

7. The method according to claim 6 , wherein heat recovered in the heat exchanger is used to supply the consumer.

8. The method according to claim 1 , wherein the consumer is a heating system which is used for heating facilities or buildings.

9. The method according to claim 1 , wherein the metallurgical slag is a nonferrous slag.

10. The method according to claim 1 , wherein a venting site provided in the region of the first section for the released air is vertically above a site for supplying the liquid slag and blowing the heated air onto the supply of liquid slag.

11. The method according to claim 1 , wherein the released air from the single working chamber is guided vertically upward, then deflected by 180°, then guided vertically downward, and then supplied again to the single working chamber through the blower.

12. The method according to claim 1 , wherein a receiving or removal element for defective products is located in the first section of the single working chamber and at least one receiving or removal element for granulated slag particles is located in the second section of the single working chamber.

Assignees

• Sms Group Gmbh
• Bergs Monika

Inventors

• Degel Rolf
• Lux Timm
• Bergs Alexander
• Borowski Nikolaus Peter Kurt

Classifications

• C21B2400/062

  Jet nozzles or pressurised fluids for cooling, fragmenting or atomising slag · CPC title

• C21B2400/08

  with energy recovery · CPC title

• C21B2400/026

  using air, inert gases or removable conductive bodies · CPC title

• C22B7/04 Primary

  Working-up slag · CPC title

• C21B3/08 Primary

  Cooling slag · CPC title