CN114854911A - Device and method for utilizing heat energy of high-temperature steel slag - Google Patents

Device and method for utilizing heat energy of high-temperature steel slag Download PDF

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Publication number
CN114854911A
CN114854911A CN202210439083.9A CN202210439083A CN114854911A CN 114854911 A CN114854911 A CN 114854911A CN 202210439083 A CN202210439083 A CN 202210439083A CN 114854911 A CN114854911 A CN 114854911A
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steel slag
temperature
slag
steel
crawler
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CN202210439083.9A
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CN114854911B (en
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晏灏
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Nanjing Yingxin Technology Co ltd
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    • CCHEMISTRY; METALLURGY
    • C21METALLURGY OF IRON
    • C21BMANUFACTURE OF IRON OR STEEL
    • C21B3/00General features in the manufacture of pig-iron
    • C21B3/04Recovery of by-products, e.g. slag
    • C21B3/06Treatment of liquid slag
    • CCHEMISTRY; METALLURGY
    • C21METALLURGY OF IRON
    • C21BMANUFACTURE OF IRON OR STEEL
    • C21B3/00General features in the manufacture of pig-iron
    • C21B3/04Recovery of by-products, e.g. slag
    • C21B3/06Treatment of liquid slag
    • C21B3/08Cooling slag
    • CCHEMISTRY; METALLURGY
    • C21METALLURGY OF IRON
    • C21BMANUFACTURE OF IRON OR STEEL
    • C21B2400/00Treatment of slags originating from iron or steel processes
    • C21B2400/02Physical or chemical treatment of slags
    • CCHEMISTRY; METALLURGY
    • C21METALLURGY OF IRON
    • C21BMANUFACTURE OF IRON OR STEEL
    • C21B2400/00Treatment of slags originating from iron or steel processes
    • C21B2400/02Physical or chemical treatment of slags
    • C21B2400/022Methods of cooling or quenching molten slag
    • C21B2400/024Methods of cooling or quenching molten slag with the direct use of steam or liquid coolants, e.g. water
    • CCHEMISTRY; METALLURGY
    • C21METALLURGY OF IRON
    • C21BMANUFACTURE OF IRON OR STEEL
    • C21B2400/00Treatment of slags originating from iron or steel processes
    • C21B2400/02Physical or chemical treatment of slags
    • C21B2400/022Methods of cooling or quenching molten slag
    • C21B2400/026Methods of cooling or quenching molten slag using air, inert gases or removable conductive bodies
    • CCHEMISTRY; METALLURGY
    • C21METALLURGY OF IRON
    • C21BMANUFACTURE OF IRON OR STEEL
    • C21B2400/00Treatment of slags originating from iron or steel processes
    • C21B2400/05Apparatus features
    • CCHEMISTRY; METALLURGY
    • C21METALLURGY OF IRON
    • C21BMANUFACTURE OF IRON OR STEEL
    • C21B2400/00Treatment of slags originating from iron or steel processes
    • C21B2400/08Treatment of slags originating from iron or steel processes with energy recovery
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02WCLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT
    • Y02W30/00Technologies for solid waste management
    • Y02W30/50Reuse, recycling or recovery technologies

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  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Manufacturing & Machinery (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Furnace Details (AREA)

Abstract

The invention relates to the technical field of industrial energy conservation, in particular to a device and a method for utilizing heat energy of high-temperature steel slag, which comprises the steps of crushing high-temperature solid steel slag (300 ℃ -1100 ℃) into high-temperature steel slag with uniform specification; introducing the high-temperature steel slag with the unified specification into a slag cooler for heat exchange, and discharging cooled steel slag; and (3) treating the cooled steel slag in the conventional steel slag treatment process (thermal braising \ stacking \ magnetic separation and the like) of a steel mill. The invention is embedded into the existing steel slag treatment process of a steel mill, and utilizes air or water to perform dividing wall type heat extraction on the high-temperature steel slag, thereby providing an efficient mode for high-quality application of steel slag heat energy. Meanwhile, the granularity of the steel slag is fine and uniform due to the early crushing treatment, so that the subsequent hot braising effect of the steel slag is promoted. The steel slag after hot braising does not need to be crushed before magnetic separation, thereby reducing the treatment cost of the steel slag.

Description

Device and method for utilizing heat energy of high-temperature steel slag
Technical Field
The invention relates to the technical field of industrial energy conservation, in particular to a device and a method for utilizing heat energy of high-temperature steel slag.
Background
In 2020, the yield of crude steel in China reaches 10.65 hundred million tons, and the first place is global; about 1.20 million tons of steel slag are generated in the steel making process. How to realize the deep and effective utilization of the steel slag is a problem worthy of people. As one of the industries with the most carbon emission in China, the steel industry has great burden and is imperative, so that the opportunity and the challenge coexist. The heat energy released by each ton of steel slag is 1770000KJ when about 0.120.14 tons of steel slag are produced for each ton of steel, the temperature of the steel slag is firstly reduced to be below 500 ℃ by a physical method from 1500 ℃ in the current mainstream steel slag treatment process, then the next treatment is carried out, the utilization of the waste heat of the steel slag is almost zero, and huge energy waste is caused.
Disclosure of Invention
The invention aims to provide a device and a method for utilizing heat energy of high-temperature steel slag, and aims to solve the problem that the waste heat utilization of the steel slag is almost zero in the conventional steel slag treatment process, so that huge energy waste is caused.
In order to achieve the above object, in a first aspect, the present invention provides an apparatus for utilizing heat energy of high temperature steel slag, comprising:
scrape the trigger, connect feed bin, high temperature breaker, receive feed bin, second crawler-type high temperature and scrape trigger, cold sediment ware and crawler-type scraper, receive the feed bin with first crawler-type high temperature scrapes trigger connection, high temperature breaker with receive the feed bin to connect, connect the feed bin with high temperature breaker connects, second crawler-type high temperature scrape trigger with connect the feed bin to connect cold sediment ware with second crawler-type high temperature scrapes trigger connection, crawler-type scraper with cold sediment ware is connected.
The slag cooler is a dividing wall type heat exchange slag cooler, and is equipment for cooling high-temperature materials.
The first crawler-type scraper machine and the second crawler-type scraper machine are a solid lump material conveying tool which is driven by a gear disc driven by a motor through combination of heat-resistant steel and a water-cooled wall.
The crushing working surface of the high-temperature crusher adopts a mode of adding a cooling jacket to heat-resistant high-strength steel to finish continuous crushing of high-temperature materials.
In a second aspect, the present invention also provides a method for utilizing heat energy of high-temperature steel slag, which is applied to the apparatus for utilizing heat energy of high-temperature steel slag according to claim 1, and comprises:
crushing the high-temperature solid steel slag into high-temperature steel slag with uniform specification and inputting the high-temperature steel slag into the material receiving bin;
introducing the high-temperature steel slag from the material receiving bin into a slag cooler through the second crawler-type high-temperature scraper machine for heat exchange to generate high-temperature hot water and hot air and cool the steel slag;
introducing the high-temperature hot water and hot air into other industrial production for recycling;
and discharging the cooled steel slag from the slag cooler, and inputting the steel slag into a subsequent steel slag treatment procedure of a steel mill for treatment through the crawler-type scraper conveyor.
The high-temperature liquid steel slag is liquid steel slag with the temperature of 1500 ℃, the high-temperature solid steel slag is steel slag with the specification of 0mm to 900mm with the temperature of 300 ℃ to 1100 ℃, and the high-temperature steel slag with the unified specification is solid steel slag with the specification of 0mm to 40mm with the temperature of 300 ℃ to 900 ℃.
The device and the method for utilizing the heat energy of the high-temperature steel slag can be embedded into the existing steel slag treatment process of a steel mill, and the high-temperature steel slag is subjected to dividing wall type heat extraction by using air or water, so that an efficient mode is provided for high-quality application of the heat energy of the steel slag. Meanwhile, as the early-stage crushing treatment is carried out, the granularity of the steel slag is fine and uniform, and the subsequent hot stewing effect of the steel slag is promoted: the slag and iron separation is better, and the stability of the steel slag after magnetic separation is better. The steel slag after hot braising does not need to be crushed before magnetic separation, thereby reducing the treatment cost of the steel slag. Has important significance for reducing the comprehensive energy consumption of iron and steel enterprises.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the embodiments or the prior art descriptions will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and other drawings can be obtained by those skilled in the art without creative efforts.
FIG. 1 is a flow chart of a method for utilizing heat energy of high-temperature steel slag according to the present invention.
FIG. 2 is a front view of the apparatus for utilizing heat energy from high temperature steel slag according to the present invention.
FIG. 3 is a top view of an apparatus for utilizing heat energy from high temperature steel slag according to the present invention.
1-a first crawler-type high-temperature scraper, 2-a receiving bin, 3-a high-temperature crusher, 4-a receiving bin, 5-a second crawler-type high-temperature scraper, 6-a slag cooler and 7-a crawler-type scraper.
Detailed Description
Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the drawings are illustrative and intended to be illustrative of the invention and are not to be construed as limiting the invention.
Referring to fig. 2 to 3, in a first aspect, the present invention provides an apparatus for utilizing heat energy of high temperature steel slag, comprising:
comprises a first crawler-type high-temperature scraper conveyor 1, a material receiving bin 2, a high-temperature crusher 3, a material receiving bin 4, a second crawler-type high-temperature scraper conveyor 5, a slag cooler 6 and a crawler-type scraper conveyor 7, wherein the material receiving bin 4 is fixedly connected with the first crawler-type high-temperature scraper conveyor 1 and is positioned on one side of the first crawler-type high-temperature scraper conveyor 1, the water-cooling high-temperature crusher 3 is fixedly connected with the material receiving bin 4 and is positioned on one side of the material receiving bin 4, the material receiving bin 2 is fixedly connected with the high-temperature crusher 3 and is positioned on one side of the high-temperature crusher 3, the second crawler-type high-temperature scraper conveyor 5 is fixedly connected with the material receiving bin 2 and is positioned on one side of the material receiving bin 2, the slag cooler 6 is fixedly connected with the second crawler-type high-temperature scraper conveyor 5 and is positioned on one side of the second crawler-type high-temperature scraper conveyor 5, and the crawler-type scraper conveyor 7 is fixedly connected with the slag cooler 6, and is positioned at one side of the slag cooler 6.
The slag cooler 6 is a dividing wall type heat exchange slag cooler, and the slag cooler 6 is equipment for cooling high-temperature materials.
The first crawler-type high-temperature scraper conveyor 1 and the second crawler-type high-temperature scraper conveyor 5 are solid lump material conveying tools which are driven by a gear disc driven by a motor through combination of heat-resistant steel and a water-cooled wall.
The crushing working surface of the high-temperature crusher 3 adopts a mode of adding a cooling jacket to heat-resistant high-strength steel to finish continuous crushing of high-temperature materials.
In a second aspect, referring to fig. 1, the present invention further provides a method for utilizing heat energy of high temperature steel slag, comprising:
s101, crushing the high-temperature solid steel slag into high-temperature steel slag with uniform specification and inputting the high-temperature steel slag into the receiving bin;
s102, introducing the high-temperature steel slag from the material receiving bin to a slag cooler through the second crawler-type high-temperature scraper machine for heat exchange to generate high-temperature hot water, hot air and cooled steel slag;
s103, introducing the high-temperature hot water and hot air into other industrial production for recycling;
s104, discharging the cooled steel slag from the slag cooler, and inputting the steel slag into a subsequent steel slag treatment procedure of a steel mill for treatment through the crawler-type scraper.
The subsequent steel slag treatment comprises the working procedures of hot disintegration, stockpiling, magnetic separation and the like.
The high-temperature liquid steel slag is liquid steel slag with the temperature of 1500 ℃, the high-temperature solid steel slag is steel slag with the specification of 0mm to 900mm with the temperature of 300 ℃ to 1100 ℃, and the high-temperature steel slag with the unified specification is solid steel slag with the specification of 0mm to 40mm with the temperature of 300 ℃ to 900 ℃.
The method for utilizing the heat energy of the high-temperature steel slag can be embedded into the existing steel slag treatment process of a steel mill, and the high-temperature steel slag is subjected to dividing wall type heat extraction by using air or water, so that an efficient mode is provided for high-quality application of the heat energy of the steel slag. Meanwhile, the granularity of the steel slag is fine and uniform due to the early crushing treatment, so that the subsequent hot braising effect of the steel slag is promoted: the slag and iron separation is better, and the stability of the steel slag after magnetic separation is better. The steel slag after hot braising does not need to be crushed before magnetic separation, thereby reducing the treatment cost of the steel slag.
While the invention has been described with reference to a preferred embodiment, it will be understood by those skilled in the art that various changes in form and detail may be made therein without departing from the spirit and scope of the invention.

Claims (6)

1. A device for utilizing heat energy of high-temperature steel slag, which is characterized in that,
scrape the trigger, connect feed bin, high temperature breaker, receive feed bin, second crawler-type high temperature and scrape trigger, cold sediment ware and crawler-type scraper, receive the feed bin with first crawler-type high temperature scrapes trigger connection, high temperature breaker with receive the feed bin to connect, connect the feed bin with high temperature breaker connects, second crawler-type high temperature scrape trigger with connect the feed bin to connect, cold sediment ware with second crawler-type high temperature scrapes trigger connection, crawler-type scraper with cold sediment ware is connected.
2. The method of claim 1, wherein the steel slag is a steel slag with high temperature, and the steel slag is a steel slag with high temperature,
the slag cooler adopts a dividing wall type heat exchange slag cooler, and the slag cooler is equipment for cooling high-temperature materials.
3. The method of claim 1, wherein the steel slag is a steel slag with high temperature, and the steel slag is a steel slag with high temperature,
the high-temperature crawler scraper conveyor is a solid lump material conveying tool which is driven by a gear disc driven by a motor by combining heat-resistant steel and a water-cooled wall.
4. The method of claim 2, wherein the steel slag is a steel slag with high temperature, and the steel slag is a steel slag with high temperature,
the crushing working surface of the high-temperature crusher adopts a mode of adding a cooling jacket to heat-resistant high-strength steel to finish continuous crushing of high-temperature materials.
5. A method for utilizing the heat energy of the high-temperature steel slag is applied to the device for utilizing the heat energy of the high-temperature steel slag as claimed in claim 1, and is characterized in that,
crushing high-temperature solid steel slag into high-temperature steel slag with uniform specification and inputting the high-temperature steel slag into the receiving bin;
introducing the high-temperature steel slag from the material receiving bin into a slag cooler through the second crawler-type high-temperature scraper machine for heat exchange to generate high-temperature hot water and hot air and cool the steel slag;
introducing the high-temperature hot water and hot air into other industrial production for recycling;
and discharging the cooled steel slag from the slag cooler, and inputting the steel slag into a subsequent steel slag treatment procedure of a steel mill for treatment through the crawler-type scraper conveyor.
6. The method of claim 5, wherein the steel slag is a steel slag with high temperature, and the steel slag is a steel slag with high temperature,
the high-temperature liquid steel slag is liquid steel slag with the temperature of 1500 ℃, the high-temperature solid steel slag is steel slag with the specification of 0mm to 900mm with the temperature of 300 ℃ to 1100 ℃, and the high-temperature steel slag with the unified specification is solid steel slag with the specification of 0mm to 40mm with the temperature of 300 ℃ to 900 ℃.
CN202210439083.9A 2022-04-22 2022-04-22 Device and method for utilizing heat energy of high-temperature steel slag Active CN114854911B (en)

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Citations (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4062672A (en) * 1974-10-21 1977-12-13 Entreprise Gagneraud Pere Et Fils Process for improving the fragmentation capability of metallurgical slags and cinders
DE3102296A1 (en) * 1981-01-24 1982-09-02 Kawasaki Jukogyo K.K. Apparatus for recovering heat from molten slag
JP2011220599A (en) * 2010-04-08 2011-11-04 Jfe Steel Corp Steel slag thermal energy recovery method
CN102443661A (en) * 2012-01-10 2012-05-09 山西太钢不锈钢股份有限公司 Hot stewing one-step water spraying method of converter steel slag
CN102952908A (en) * 2012-10-15 2013-03-06 唐山钢铁国际工程技术有限公司 Equipment for steel slag air quenching and waste heat recycling
US20130240415A1 (en) * 2012-03-19 2013-09-19 Mid-American Gunite, Inc. Method and system for processing slag material
JP2016102261A (en) * 2014-11-12 2016-06-02 Jfeスチール株式会社 Method and system for recovering heat of slag
CN109182628A (en) * 2018-08-27 2019-01-11 浙江哈斯科节能技术有限公司 A kind of cooling equipment of hot melt steel slag dry method
CN110530165A (en) * 2019-09-26 2019-12-03 中冶节能环保有限责任公司 A kind of steel slag waste heat is using device and utilizes method
CN112251548A (en) * 2020-08-29 2021-01-22 钟赛梅 Steel slag waste heat utilization device and operation mode thereof
WO2021115029A1 (en) * 2019-12-12 2021-06-17 青岛理工大学 Iron-containing metallurgical slag granule graded waste heat recovery and direct reduction system and method
CN214422670U (en) * 2021-03-19 2021-10-19 中冶节能环保有限责任公司 High temperature slag waste heat recovery device

Patent Citations (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4062672A (en) * 1974-10-21 1977-12-13 Entreprise Gagneraud Pere Et Fils Process for improving the fragmentation capability of metallurgical slags and cinders
DE3102296A1 (en) * 1981-01-24 1982-09-02 Kawasaki Jukogyo K.K. Apparatus for recovering heat from molten slag
JP2011220599A (en) * 2010-04-08 2011-11-04 Jfe Steel Corp Steel slag thermal energy recovery method
CN102443661A (en) * 2012-01-10 2012-05-09 山西太钢不锈钢股份有限公司 Hot stewing one-step water spraying method of converter steel slag
US20130240415A1 (en) * 2012-03-19 2013-09-19 Mid-American Gunite, Inc. Method and system for processing slag material
CN102952908A (en) * 2012-10-15 2013-03-06 唐山钢铁国际工程技术有限公司 Equipment for steel slag air quenching and waste heat recycling
JP2016102261A (en) * 2014-11-12 2016-06-02 Jfeスチール株式会社 Method and system for recovering heat of slag
CN109182628A (en) * 2018-08-27 2019-01-11 浙江哈斯科节能技术有限公司 A kind of cooling equipment of hot melt steel slag dry method
CN110530165A (en) * 2019-09-26 2019-12-03 中冶节能环保有限责任公司 A kind of steel slag waste heat is using device and utilizes method
WO2021115029A1 (en) * 2019-12-12 2021-06-17 青岛理工大学 Iron-containing metallurgical slag granule graded waste heat recovery and direct reduction system and method
CN112251548A (en) * 2020-08-29 2021-01-22 钟赛梅 Steel slag waste heat utilization device and operation mode thereof
CN214422670U (en) * 2021-03-19 2021-10-19 中冶节能环保有限责任公司 High temperature slag waste heat recovery device

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