Blast furnace slag hardening and tempering method and blast furnace slag hardening and tempering device

Abstract

The invention discloses a blast furnace slag hardening and tempering method and a blast furnace slag hardening and tempering device, the blast furnace slag hardening and tempering method comprises the following steps: adding a hardening and tempering agent into liquid blast furnace slag, the hardening and tempering agent being rich in SiO2 and Al2O3; the weight ratio of the liquid blast furnace slag to the hardening and tempering agent is (85-95): (5-15), and after the hardening and tempering agent is added, the acidity of the liquid blast furnace slag is 1.2-1.4, the viscosity is 1-3 Pa.s, and the temperature is 1350-1400 DEG C. The invention further provides a blast furnace slag tempering device, and based on the method and the device, the problems that existing blast furnace slag tempering is poor in chemical stability and component uniformity are solved.

Description

Technical Field

[0001] The invention belongs to the technical field of blast furnace slag tempering, and in particular relates to a blast furnace slag tempering method and a device thereof. Background Art

[0002] Blast furnace slag is a byproduct produced during the blast furnace ironmaking process. Its main components include silicates, aluminates and calcium-magnesium compounds, and it has potential resource utilization value. In the prior art, blast furnace slag is often used as a raw material for slag cement, roadbed material or soil conditioner. However, due to the volatility of the chemical composition of blast furnace slag and the instability of the cooling method, its efficient utilization is limited.

[0003] In order to improve the resource utilization efficiency of blast furnace slag, the existing technology usually adopts the tempering method, which adjusts the chemical composition of blast furnace slag by adding tempering agents to the blast furnace slag. For example, some tempering agents are mainly calcium-rich and magnesium-rich materials, which can optimize the silicon-calcium ratio or silicon-magnesium ratio in blast furnace slag. However, these tempering methods also have obvious defects:

[0004] 1. Insufficient chemical stability: After adding traditional conditioning agents such as limestone or dolomite, the composition fluctuates easily due to the violent high-temperature reaction, which in turn affects the consistency of blast furnace slag performance.

[0005] 2. Poor composition uniformity: Some tempering agents are difficult to mix evenly into liquid blast furnace slag, resulting in uneven distribution of components and reducing the performance quality of subsequent products.

[0006] The information disclosed in this background technology section is only intended to enhance the understanding of the overall background of the invention and should not be regarded as an acknowledgment or any form of suggestion that the information constitutes the prior art already known to a person skilled in the art. Summary of the invention

[0007] In order to solve the technical problems of poor chemical stability and poor composition uniformity in the prior art of blast furnace slag tempering, a blast furnace slag tempering method and a device thereof are provided.

[0008] The first aspect of the present invention provides a blast furnace slag tempering method, comprising: adding a tempering agent to liquid blast furnace slag, wherein the tempering agent is rich in SiO2 and Al2O3; wherein the SiO2 content is 30%-80%, the Al2O3 content is 5%-40%, and the rest is impurities;

[0009] The weight ratio of the liquid blast furnace slag to the tempering agent is 85-95:5-15.

[0010] In some embodiments, the conditioning agent is waste from the steel production process, preferably, the conditioning agent is iron ore waste and / or fly ash;

[0011] and / or, the particle size of the conditioning agent is below 100 μm;

[0012] And / or, after adding the conditioning agent, the liquid blast furnace slag has an acidity of 1.2-1.4, a viscosity of 1-3 Pa·s, and a temperature of 1350-1400°C.

[0013] A second aspect of the present invention provides a blast furnace slag tempering device, comprising:

[0014] The main body has a tempering area inside for the liquid blast furnace slag to react with the tempering agent to generate modified slag and high-heat exhaust gas;

[0015] A liquid blast furnace slag introduction portion is provided on the main body portion and is used to introduce liquid blast furnace slag into the tempering area of ​​the main body portion;

[0016] A conditioning agent spraying portion, disposed on the main body portion, for spraying the conditioning agent to the conditioning area of ​​the main body portion;

[0017] The gas combustion part is arranged on the main body part and is used to provide a heat source to the tempering area of ​​the main body part.

[0018] In some embodiments, the body portion comprises:

[0019] A tempering container, with an opening at the top and a discharge port at the bottom, wherein the tempering container has a tempering area for reacting liquid blast furnace slag with a tempering agent to generate reformed slag and high-temperature exhaust gas;

[0020] The gas collecting hood covering the top opening area of ​​the conditioning container is arranged at the top opening of the conditioning container.

[0021] In some embodiments, the liquid blast-furnace slag introduction part is disposed on the tempering container or the gas collecting hood, and is used to introduce liquid blast-furnace slag into the tempering area.

[0022] In some embodiments, the conditioning agent spraying portion is disposed on the side wall of the conditioning container and is used to spray the conditioning agent into the conditioning area;

[0023] The conditioning agent injection parts are provided with a plurality of groups, and preferably, the conditioning agent injection parts are provided with 2 groups.

[0024] In some embodiments, the gas combustion part is disposed on the gas collecting hood to provide a heat source to the tempering area.

[0025] In some embodiments, the conditioning agent injection unit includes a main spray gun and a branch spray gun, the main spray gun is arranged on the upper part of the branch spray gun, and the branch spray gun is provided in a plurality of groups.

[0026] In some embodiments, when the blast furnace slag tempering device is in use, the tempering agent injection portion sprays the tempering agent into the tempering area of ​​the main part, so that the temperature of the liquid blast furnace slag is reduced to 1100-1400°C, and the temperature of the modified slag generated in the main part is maintained at 1350-1400°C by the gas combustion portion, and the gas combustion portion burns gas to produce CO, the nozzle of the tempering agent injection portion is located below the liquid level in the main part, and the gas combustion portion is located above the liquid level in the main part.

[0027] In some embodiments, after the blast furnace slag tempering device completes the preparation of modified slag, the gas combustion part continues to burn the gas for 30-60 minutes to completely dissolve the tempering agent, and at the same time, the temperature of the modified slag in the main part is controlled at 1350-1400°C, the acidity is controlled at 1.2-1.4, and the viscosity is controlled at 1-3Pa·s.

[0028] In some embodiments, the parameters of the high-temperature exhaust gas are: temperature 1400-1500° C., pressure 0.1 MPa, and CO content less than 3%.

[0029] In some embodiments, the conditioning agent injection unit includes: a first spray gun, the first spray gun includes a main spray gun and a branch spray gun, the spraying pressure of the main spray gun is 0.3-1.0Mpa, and the spraying pressure of the branch spray gun is 0.3-0.8Mpa.

[0030] In some embodiments, the gas combustion part includes a second spray gun, and the spraying pressure of the second spray gun is 0.3-0.7 MPa.

[0031] In some embodiments, a valve and a flow meter are installed at the discharge port of the tempering container, wherein the valve is used to control the discharge of the material generated inside the tempering container, and the flow meter is used to measure the flow rate of the material generated inside the tempering container at the discharge port.

[0032] The branch spray guns are provided with a main spray gun disposed on the upper part of the branch spray guns, and the branch spray guns are provided with a plurality of groups.

[0033] A third aspect of the present invention provides a blast furnace slag treatment method based on the above-mentioned blast furnace slag tempering device, comprising:

[0034] Introducing liquid blast furnace slag into a tempering container, and adding a tempering agent into the tempering container through a main spray gun and a branch spray gun, wherein the weight ratio of the liquid slag to the tempering agent is 85-95:5-15;

[0035] The liquid blast furnace slag and the tempering agent mixture are sprayed and heated to 1350-1400°C through the gas combustion section for 30-60 minutes.

[0036] In some embodiments, after adding the conditioning agent, the liquid blast furnace slag has an acidity of 1.2-1.4 and a viscosity of 1-3 Pa·s;

[0037] And / or, the spraying pressure of the main spray gun is 0.3-1.0Mpa, and the spraying pressure of the branch spray gun is 0.3-0.8Mpa;

[0038] And / or, the injection pressure of the gas combustion part is 0.3-0.7Mpa, and the CO content in the furnace is controlled to be less than 3% during the injection process.

[0039] Compared with the prior art, the technical effects achieved by the present invention are as follows:

[0040] (1) The tempering agent of the present invention is rich in SiO2 and Al2O3, which effectively supplements the deficiency of silicon-aluminum compounds in blast furnace slag, optimizes its chemical composition, improves the chemical composition stability of blast furnace slag, and provides a basis for subsequent processing and high value-added utilization.

[0041] (2) The tempering agent used has good reaction compatibility with liquid blast furnace slag and will not undergo violent reactions under high temperature conditions. The operation is safer, the process is more controllable, and it is convenient for large-scale industrial application.

[0042] (3) The present invention uses industrial solid waste generated during steel processing as a slag conditioning agent to convert the slag into a slag wool product. This not only increases the added value of blast furnace slag products, but also consumes industrial solid waste while recovering slag waste heat, which is beneficial to energy conservation and environmental protection. It effectively solves the technical problem that the by-product added value obtained by the slag treatment process in the prior art is low, which not only fails to fully realize the comprehensive utilization of resources, but also produces a large amount of industrial solid waste. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Figure 1 It is a schematic structural diagram of a blast furnace slag tempering device in a slag treatment device provided in one embodiment of the present invention;

[0044] Figure 2 It is a working flow chart of the slag treatment equipment provided in one embodiment of the present invention. DETAILED DESCRIPTION

[0045] The technical solution of the present invention is described below by specific embodiments in conjunction with the accompanying drawings. It should be understood that one or more steps mentioned in the present invention do not exclude the existence of other methods and steps before and after the combination step, or other methods and steps can be inserted between these explicitly mentioned steps. It should also be understood that these examples are only used to illustrate the present invention and are not used to limit the scope of the present invention. Unless otherwise specified, the numbering of each method step is only for the purpose of identifying each method step, and is not intended to limit the order of arrangement of each method or to define the scope of implementation of the present invention. Changes or adjustments in their relative relationships can also be regarded as the scope of implementation of the present invention without substantial changes in the technical content.

[0046] The sources of the raw materials and instruments used in the examples are not particularly limited and can be purchased from the market or prepared according to conventional methods known to those skilled in the art.

[0047] Example:

[0048] A blast furnace slag treatment method comprises: adding a tempering agent rich in SiO2 and Al2O3 (wherein the SiO2 content is 30%-80%, the Al2O3 content is 5%-40%, and the rest is impurities) to liquid blast furnace slag, preferably waste materials such as iron ore waste rock and / or fly ash generated in the steel production process, the ratio of the liquid blast furnace slag to the tempering agent is 85-95:5-15, and after the tempering agent is added, the liquid blast furnace slag has an acidity of 1.2-1.4, a viscosity of 1-3 Pa·s, and a temperature of 1350-1400°C; the particle size of the tempering agent is below 100 μm.

[0049] like Figure 1 , Figure 2 As shown, in one embodiment, the blast furnace slag tempering device 10 includes a main body, a liquid blast furnace slag introduction part, a tempering agent injection part and a gas combustion part.

[0050] The main body has a tempering area inside for liquid blast furnace slag to react with a tempering agent to generate modified slag and high-temperature exhaust gas.

[0051] The liquid blast-furnace slag introduction portion is disposed on the main body portion and is used to introduce the liquid blast-furnace slag into the tempering region of the main body portion.

[0052] The conditioning agent injection part is arranged on the main body part, and is used to inject the conditioning agent into the conditioning area of ​​the main body part, wherein the injection pressure of the conditioning agent injection part is not less than 0.3Mpa;

[0053] The gas combustion part is arranged on the main body part and is used to provide a heat source to the tempering area of ​​the main body part;

[0054] In some embodiments, the main body includes a tempering container 107 and a gas collecting hood 103. The tempering container 107, as a reaction container, can be understood as a tempering furnace, which is a shell with a top opening and a discharge port 104 on the lower right wall and a tempering area formed inside; in some embodiments, the tempering container 107 is welded from steel plates and can withstand high temperature and high pressure. The inner side of the tempering container 107 is configured with a container lining 106, which directly contacts liquid blast furnace slag and tempering agents in the tempering container 107. The container lining is selected as an acid container lining, which has good heat resistance and heat insulation properties, effectively protects the structure of the tempering container 107 and reduces heat loss. The tempering container 107 is welded from steel plates and can also be used to wrap and protect the internal container lining 106 structure. In some embodiments, a support part 108 is installed on the bottom outer wall of the tempering container 107 to support and fix the tempering container 107 to ensure the stability and safety of the tempering container 107 and its components during operation. The support part 108 is usually composed of components such as a bracket, a base, and anchor bolts. Its structure and strength should be adjusted according to the weight, size, and vibration of the blast furnace slag tempering device 10 during operation. The gas collecting hood 103 is installed at the opening of the upper part of the tempering container 107, and serves as the top sealing component of the tempering container 107. It is used to collect the high-temperature exhaust gas 901 discharged from the tempering container 107, collect the high-temperature exhaust gas, and prevent the high-temperature exhaust gas from leaking into the surrounding environment. The material of the gas collecting hood 103 needs to have high temperature resistance and corrosion resistance to ensure normal operation in a long-term high-temperature exhaust gas environment; the gas collecting hood 103 is connected to the first connecting pipeline 40.

[0055] In some embodiments, the liquid blast furnace slag introduction part includes a slag groove 101. The slag groove 101 is inserted on the side wall of the gas collecting hood 103, and can also be inserted on the side wall of the quenching and tempering container 107. The discharge port of the slag groove 101 (the right end of the slag groove 101) is located above the quenching and tempering area of ​​the quenching and tempering container 107, so that the liquid blast furnace slag 801 can be introduced into the quenching and tempering area of ​​the quenching and tempering container 107 through the slag groove 101 and its discharge port;

[0056] In some embodiments, the tempering agent injection unit includes a first spray gun 102. The first spray gun 102 is installed on the side wall of the tempering container 107, and its nozzle (the right end of the first spray gun 102) is located in the tempering area of ​​the tempering container 107, so that the tempering agent 802 can be introduced into the tempering area of ​​the tempering container 107 through the first spray gun 102 and its nozzle; in some embodiments, the first spray gun 102 includes a main spray gun 1021 and a branch spray gun 1022, and the main spray gun 1021 is arranged above the branch spray gun 1022; in some embodiments, the main spray gun 1021 and the branch spray gun 1022 are both made of stainless steel, and are covered with refractory materials, and the outer refractory materials are selected as acidic refractory materials, and the spray gun cooling method is water cooling; In some embodiments, the blowing pressure of the main spray gun 1021 is 0.3-1.0Mpa, and the blowing pressure of the branch spray gun 1022 is 0.3-0.8Mpa. The main spray gun 1021 and the branch spray gun 1022 serve to temper the liquid blast furnace slag so that the components of the liquid blast furnace slag meet the requirements of the next step of producing slag wool. At the same time, the main spray gun 1021 and the branch spray gun 1022 also stir the liquid blast furnace slag to make the slag tempering and heating process react more evenly. If the blowing pressure is lower than the above range, it cannot be fully stirred. If it is higher than this range, it will cause waste of kinetic energy and damage the spray gun, reduce the service life of the spray gun, and at the same time increase the material requirements of the first spray gun 102.

[0057] In some embodiments, the gas combustion unit includes a second spray gun 105. The second spray gun 105 is inserted on the top wall of the gas hood 103 (in one embodiment, the top wall of the gas hood 103 has a hole, and the second spray gun 105 is roughly inserted on the top wall of the gas hood 103), and its nozzle (the lower end of the second spray gun 105) is located directly above the tempering area of ​​the tempering container 107, so that the industrial gas 803 can be introduced into the tempering area of ​​the tempering container 107 through the second spray gun 105 and its nozzle, which plays a role in heating the tempering area of ​​the tempering container 107; in some embodiments In the example, the second spray gun 105 is made of stainless steel and is covered with refractory material, and the refractory material is selected as acidic refractory material; in some embodiments, the blowing pressure of the second spray gun 105 is 0.3-0.7Mpa, which plays the role of heating and stirring the tempering area of ​​the tempering container 107, improving the reaction efficiency and promoting the uniformity of the reaction; in some embodiments, the industrial gas 803 can be selected from the waste gas generated by the industrial furnace in the steel plant, including but not limited to blast furnace gas, converter gas and coke oven gas.

[0058] In some embodiments, a valve 1041 and a flow meter 1042 are installed at the outlet 104 of the conditioning container 107 . The valve 1041 is used to control the switch of the outlet 104 of the conditioning container 107 , and the flow meter 1042 is used to detect the flow at the outlet 104 of the valve 1041 .

[0059] Working principle of blast furnace slag tempering device 10:

[0060] (i) After the blast furnace tapping process is completed, the blast furnace slag tapping process is started. First, the liquid blast furnace slag 801 (acidity Mk=1.0-1.4, temperature 1450-1550°C) in the blast furnace tapping yard is introduced into the tempering area of ​​the tempering container 107 through the slag groove 101, and at the same time, the tempering agent 802 (the tempering agent 802 can be selected from iron ore waste rock and fly ash and other steel production process wastes rich in SiO2 and Al2O3) with a particle size controlled below 100μm is sprayed into the tempering container 107 through the first spray gun 102. The weight ratio of the liquid blast furnace slag 801 to the tempering agent 802 is 85-9:5-15, so that the nozzle of the first spray gun 102 is located below the liquid surface of the tempering area of ​​the tempering container 107, and the nozzle of the second spray gun 105 is located above the liquid surface of the tempering area of ​​the tempering container 107. In addition, the spraying carrier gas of the first spray gun 102 is compressed air. Since the addition of the tempering agent 802 will reduce the temperature of the liquid blast furnace slag 801 to 1100-1400°C, the production of slag wool needs to ensure that the temperature of the modified slag 804 is maintained at 1350- 1400℃, so the second spray gun 105 is needed to spray industrial gas 803 into the tempering container 107. The industrial gas 803 mainly uses blast furnace gas. The theoretical combustion temperature of blast furnace gas is 1400-1500℃, which can effectively provide a heat source for the tempering container 107. When the heat is insufficient, a small amount of coke oven gas or converter gas can be mixed to supplement the heat. The theoretical combustion temperature of converter gas is 1600-1800℃, and the theoretical combustion temperature of coke oven gas is 1900-2100℃. During the spraying process, the CO content in the furnace is controlled to be less than 3% ( A CO content exceeding 3% will affect subsequent waste gas recovery. The generation of CO is caused by incomplete combustion of industrial gas, which can be solved by introducing compressed air; if the problem cannot be solved, the industrial gas can be fully burned by enriching oxygen in the compressed air by 1-3% to control the CO content) so that the high-temperature exhaust gas 901 can be recycled in the next step. The high-temperature exhaust gas 901 with a temperature of 1400-1500°C, a pressure of 0.1Mpa, and CO% <3% recovered by the gas collecting hood 103 enters the high-temperature exhaust gas recycling device 30 through the first connecting pipeline 40.

[0061] (ii) After the blast furnace slag-discharging process is completed, the tempering container 107 continues to spray the tempering agent 802 and the industrial gas 803 for 30-60 minutes to promote the complete dissolution of the tempering agent 802. At the same time, the temperature of the modified slag 804 in the tempering container 107 is controlled at 1350-1400°C, the acidity is controlled at 1.2-1.4, and the viscosity is controlled at 1-3Pa·s. If the spraying time is too short, the tempering agent 802 cannot be completely melted, and if it is too long, it will cause energy waste. The viscosity of the modified slag 804 increases with the increase of temperature. The temperature of the modified slag is maintained and the viscosity of the modified slag is controlled within a reasonable range to ensure that the modified slag meets the process requirements of the next link. Furthermore, the fiberizing effect of slag is not good if it is not within this range and does not meet the requirements of the next process. If the acidity or viscosity exceeds the above range, the fiberized slag wool fiber will be too long, and if the acidity or viscosity is lower than the above range, the fiberized slag wool fiber will be too short. The reaction is terminated, and the injection of the conditioning agent 802 and the industrial gas 803 is terminated. The liquid blast furnace slag 801 is converted into modified slag 804 after conditioning. The valve 1041 at the discharge port of the conditioning container 107 is opened, and the modified slag 804 is added to the fiberizing device 201 for centrifugal cottonizing. At the same time, the discharge speed and flow rate of the valve 1041 are adjusted according to the feedback data of the flow meter 1042.

[0062] like Figure 2 As shown, the present invention provides a blast furnace slag processing equipment, including: a blast furnace slag tempering device 10, a reformed slag processing device 20, a first waste heat power generation device (high-heat exhaust gas recycling device) 30, a second waste heat power generation device (low-heat exhaust gas recycling device) 50 and connecting pipelines.

[0063] The blast furnace slag tempering device 10 is used to react liquid blast furnace slag 801 with a tempering agent 802 to generate modified slag 804 and high-temperature exhaust gas 901, wherein the weight ratio of liquid blast furnace slag to the tempering agent is 85-95:5-15, the particle size of the tempering agent is controlled below 100μm, and the parameters of the high-temperature exhaust gas are: temperature 1400-1500℃, pressure 0.1Mpa, and CO content less than 3%.

[0064] The reformed slag processing device 20 is connected to the blast furnace slag tempering device 10, and is used to process the reformed slag in the blast furnace slag tempering device 10 into a slag wool board.

[0065] The connecting pipeline includes a first connecting pipeline 40 and a second connecting pipeline 60;

[0066] The two ends of the first connecting pipeline 40 are respectively connected to the blast furnace slag tempering device 10 and the high-heat waste gas recycling device 30, so as to connect the blast furnace slag tempering device 10 with the high-heat waste gas recycling device 30, so that the high-heat waste gas 901 generated by the blast furnace slag tempering device 10 can be transported to the high-heat waste gas recycling device 30 through the first connecting pipeline 40, and the high-heat waste gas recycling device 30 is used to convert the received high-heat waste gas 901 generated by the blast furnace slag tempering device 10 into low-heat waste gas 904 and the first electric energy 903, wherein the parameters of the low-heat waste gas are: temperature 140-200°C, pressure 0.1Mpa, CO content less than 3%;

[0067] The two ends of the second connecting pipeline 60 are respectively connected to the first waste heat power generation device (high-heat exhaust gas recycling device) 30 and the second waste heat power generation device (low-heat exhaust gas recycling device) 50, so as to connect the high-heat exhaust gas recycling device 30 with the low-heat exhaust gas recycling device 50, so that the low-heat exhaust gas 904 generated by the high-heat exhaust gas recycling device 30 is transported to the low-heat exhaust gas recycling device 50 through the second connecting pipeline 60, and the low-heat exhaust gas recycling device 50 is used to convert the received low-heat exhaust gas 904 generated by the high-heat exhaust gas recycling device 30 into low-temperature exhaust gas 907 and second electric energy 906, wherein the parameters of the low-temperature exhaust gas are: temperature 50-60°C, pressure 0.1Mpa, CO content less than 3%.

[0068] The connecting pipeline is provided with an air inducing device 70, which is used to adjust the flow rate and flow direction of the gas in the connecting pipeline.

[0069] When the slag treatment equipment is working, the blast furnace slag tempering device 10 is first used to react the liquid blast furnace slag 801 with the tempering agent 802 to generate modified slag 804 and high-heat waste gas 901, and then the modified slag processing device 20 is used to receive the modified slag 804 in the blast furnace slag tempering device 10, and the modified slag 804 in the blast furnace slag tempering device 10 is processed into slag wool board 807, and then the high-heat waste gas recycling device 30 is used to receive the high-heat waste gas generated by the blast furnace slag tempering device 10 through the first connecting pipeline 40. Gas 901 and converts the high-heat exhaust gas 901 into low-heat exhaust gas 904 and the first electrical energy 903, and finally uses the low-heat exhaust gas recycling device 50 to receive the low-heat exhaust gas 904 generated by the high-heat exhaust gas recycling device 30 through the second connecting pipeline 60 and converts the low-heat exhaust gas 904 into low-temperature exhaust gas 907 and the second electrical energy 906. During this process, the induced draft device 70 is in a working state and introduces the gas in the connecting pipeline into the corresponding high-heat exhaust gas recycling device 30 and the low-heat exhaust gas recycling device 50.

[0070] In one embodiment, the reformed slag processing device 20 includes a fiber-forming device 201 and a solidification and molding device 202 .

[0071] The fiber-forming device 201 is used to process the modified slag 804 generated by the blast furnace slag tempering device 10 into slag cotton yarn 805; it is understandable that the fiber-forming device 201 can be selected to include but not limited to a centrifugal spinning machine, a multi-roller centrifuge or a high-speed blowing machine.

[0072] The curing and forming device 202 is used to react the slag wool filaments 805 generated by the fiber forming device 201 with the binder 806 to form a slag wool board 807. In one embodiment, the curing and forming device 202 includes a cotton collector and a curing furnace.

[0073] Working principle of the reformed slag processing device 20: the reformed slag 804 can be passed through the fiber forming device 201 to obtain slag wool filaments 805, and the slag wool filaments 805 are sent to the cotton collector in the curing and molding device 202. The cotton collector conveys the slag wool filaments 805 to the cotton collector through negative pressure wind; a binder 806 is added to the slag wool filaments 805 to improve the strength of the slag wool filaments 805; the binder 806 can use organic binders such as phenolic resin and urea-formaldehyde resin, and the added amount is preferably 2-10% of the weight of the integrated slag wool filaments 805, which can be adjusted according to actual conditions; the binder 806 can be uniformly added to the slag wool filaments 805 by methods including but not limited to spraying, dipping, etc. The slag wool filaments 805 that have been collected are reduced in volume to form a fluffy cotton felt-like material, and a slag wool board 807 with a thickness of 30-100 mm is obtained by calendering with a pressure roller. The cotton collection process can use processes including but not limited to the pendulum method and the sedimentation method. The slag wool board 807 after the cotton collection is passed through a curing furnace to fully cure the binder 806. The curing temperature is preferably 200-300°C, and the curing time is preferably 2-5 hours. The specific curing parameters can be adjusted according to the type and amount of the binder 806 and the thickness of the slag wool board 807. The slag wool board 807 is cured and formed after leaving the curing furnace. The formed slag wool board 807 is cut and packaged to obtain a finished product, which is finally shipped and sold.

[0074] In one embodiment, the high-heat waste gas recycling device 30 includes a first waste heat boiler 301 and a first generator set 302. The first waste heat boiler 301 is connected to the blast furnace slag conditioning device 10 through a first connecting pipeline 40, and is used to convert the high-heat waste gas 901 generated by the blast furnace slag conditioning device 10 and the distilled water inside the first waste heat boiler 301 into superheated saturated steam 902 by superheating; the first generator set 302 is used to convert the superheated saturated steam 902 generated by the first waste heat boiler 301 into first electric energy 903, low-heat waste gas 904, and distilled water condensed and refluxed into the first waste heat boiler 301. In one embodiment, the first generator set 302 is a steam turbine generator set.

[0075] Specifically, the saturated steam 905 in the present invention refers to water vapor with a temperature of 110-120°C, and the superheated saturated steam 902 refers to water vapor with a temperature of 400-600°C. The high-temperature exhaust gas 901 with a temperature of 1400-1500°C recovered by the gas collecting hood 103 enters the first waste heat boiler 301 in the high-temperature exhaust gas recycling device 30. The high-temperature exhaust gas 901 entering the first waste heat boiler 301 exchanges heat with the distilled water in the first waste heat boiler 301 to form superheated saturated steam 902 with a temperature of 400-600°C. The superheated saturated steam 902 drives the steam turbine of the first generator set 302 in the high-temperature exhaust gas recycling device 30 to work. In this process, the heat energy and pressure energy are converted into the mechanical energy of the steam turbine. The mechanical energy drives the first generator in the first generator set 302 to work to generate the first electric energy 903. The first electric energy 903 is transmitted through the power grid for use within the factory or for civilian use outside the factory. The superheated saturated steam 902 drives the steam turbine in the first generator set 302 to work, and then enters the first condenser in the first generator set 302, exchanges heat with the cooling water, and condenses and re-enters the first waste heat boiler 301.

[0076] In one embodiment, a denitrification point is provided inside the first waste heat boiler 301 in the high-temperature exhaust gas recycling device 30. The denitrification point uses processes including but not limited to SNCR and SCR, and the position of the denitrification point can be adjusted according to different processes. A denitrification agent 3012 is sprayed from the denitrification point into the first waste heat boiler 301. The denitrification agent 3012 includes but is not limited to substances such as ammonia gas, ammonia water and urea, which can eliminate nitrogen oxides in the exhaust gas.

[0077] In one embodiment, the slag treatment equipment also includes a desulfurization recovery device 100 connected to the second connecting pipeline 60. The desulfurization recovery device 100 is used to desulfurize the low-heat waste gas 904 generated by the high-heat waste gas recycling device 30 to obtain a low-heat waste gas 904 with a temperature of 140-200°C, a pressure of 0.1Mpa, and CO% <3%, and to recover the dust generated after desulfurization.

[0078] Specifically, the high-heat exhaust gas recycling device 30 outputs the first electric energy 903 and converts the high-heat exhaust gas 901 with a temperature of 400-600°C into a low-heat exhaust gas 904 with a temperature of 140-200°C. The low-heat exhaust gas 904 enters the desulfurization recovery device 100 through the second connecting pipeline 60. The desulfurization injection point in the desulfurization recovery device 100 injects the Ca-based desulfurizer 1002 into the flue of the desulfurization recovery device 100. The sulfur-containing low-heat exhaust gas 904 and the Ca-based desulfurizer 1002 generate CaSO4-containing dust 1003, which falls into the dust removal bag 1004 in the desulfurization recovery device 100 for recovery. After collection, the finished product can be transported out for use as a sintering mixed material, or as a raw material for brick making or roadbed filling. The desulfurization process can include but is not limited to the SDS dry desulfurization process.

[0079] In one embodiment, the low-heat exhaust gas recycling device 50 includes a second waste heat boiler 501 and a second generator set 502. The second waste heat boiler 501 is connected to the high-heat exhaust gas recycling device 30 through a second connecting pipeline 60, and is used to convert the low-heat exhaust gas 904 generated by the high-heat exhaust gas recycling device 30 and the distilled water inside the second waste heat boiler 501 into saturated steam 905 (saturated steam 905 refers to water vapor with a temperature of 110-120°C); the second generator set 502 is used to convert the saturated steam 905 generated by the second waste heat boiler 501 into second electric energy 906, low-temperature exhaust gas 907, and distilled water condensed and refluxed into the second waste heat boiler 501. In one embodiment, the second generator set 502 is an ORC generator set.

[0080] After desulfurization and dust removal, the low-heat exhaust gas 904 with a temperature of 140-200° C. is sent to the second waste heat boiler 501 in the low-heat exhaust gas recycling device 50 . The low-heat exhaust gas 904 entering the second waste heat boiler 501 exchanges heat with the distilled water in the second waste heat boiler 501. The distilled water in the second waste heat boiler 501 forms saturated steam 905 with a temperature of 110-120°C. The saturated steam 905 transfers heat to the evaporator of the second generator set 502 in the low-heat exhaust gas recycling device 50. The organic working medium in the evaporator absorbs heat and quickly vaporizes, changing from a liquid state to a high-temperature and high-pressure gas state. The high-temperature and high-pressure gaseous organic working medium enters the expander of the second generator set 502 in the low-heat exhaust gas recycling device 50 and expands inside it, thereby driving the rotor of the expander of the second generator set 502 in the low-heat exhaust gas recycling device 50 to rotate. The expander of the second generator set 502 in the low-heat exhaust gas recycling device 50 drives the second generator in the second generator set 502 to work, thereby outputting second electric energy 906. The second electric energy 906 is transmitted through the power grid for use within the factory or for civilian use outside the factory. After working, the saturated steam 905 enters the second condenser of the second generator set 502, exchanges heat with the cooling water and condenses before re-entering the second waste heat boiler 501; after working, the gaseous organic working fluid enters the third condenser of the second generator set 502, exchanges heat with the cooling water and re-condenses into liquid before entering the evaporator of the second generator set 502.

[0081] The low-heat waste gas recycling device 50 outputs the second electric energy 906 and converts the low-heat waste gas 904 with a temperature of 140°C-200°C into a low-temperature waste gas 907 with a temperature of 50-60°C. The waste gas in this state has no economic utilization value and meets the environmental emission requirements. Finally, the low-temperature waste gas 907 in the low-heat waste gas recycling device 50 is discharged from the waste gas chimney 701 through the induced draft device 70, and can be directly discharged to the atmosphere or used as a spray carrier for the first spray gun 102 in the blast furnace slag tempering device 10, so as to realize the internal circulation of the gas in the system.

[0082] In the present invention, the temperature of the high-heat exhaust gas 901 is 1400-1500°C, the temperature of the low-heat exhaust gas 904 is 140-200°C, and the temperature of the low-temperature exhaust gas 907 is 50-60°C. If the high-heat exhaust gas 901 is directly converted into the low-temperature exhaust gas 907 after one treatment, the investment cost is high and the process is difficult. Therefore, two sets of waste heat power generation devices are set up for the waste heat utilization to perform graded utilization of the high-heat exhaust gas 901. The high-heat exhaust gas 901 is first converted into the low-heat exhaust gas 904, and then the low-heat exhaust gas 904 is converted into the low-temperature exhaust gas 907.

[0083] In one embodiment, the induced draft device 70 is also used to introduce the low-temperature exhaust gas 907 generated by the low-heat exhaust gas recycling device 50 into the first lance 102 in the blast furnace slag tempering device 10 as a spraying carrier.

[0084] In some implementations, the present invention provides a blast furnace slag treatment method, which is based on a slag treatment device, and the specific steps are as follows:

[0085] First, a blast furnace slag tempering device 10 is used to react liquid blast furnace slag 801 with a tempering agent 802 to generate modified slag 804 and high-temperature exhaust gas 901, wherein the weight ratio of liquid blast furnace slag to the tempering agent is 85-95:5-15, the particle size of the tempering agent is controlled below 100 μm, and the parameters of the high-temperature exhaust gas are: temperature 1400-1500°C, pressure 0.1Mpa, and CO content less than 3%;

[0086] Then, the reformed slag processing device 20 is used to receive the reformed slag 804 in the blast furnace slag tempering device 10, and the reformed slag 804 in the blast furnace slag tempering device 10 is processed into a slag wool board;

[0087] Then, the high-heat waste gas recycling device 30 receives the high-heat waste gas generated by the blast furnace slag tempering device 10 through the first connecting pipeline 40 and converts the high-heat waste gas into low-heat waste gas and the first electric energy, wherein the parameters of the low-heat waste gas are: temperature 140-200° C., pressure 0.1 MPa, CO content less than 3%;

[0088] Finally, the low-heat exhaust gas recycling device 50 receives the low-heat exhaust gas generated by the high-heat exhaust gas recycling device 30 through the second connecting pipeline 60 and converts the low-heat exhaust gas into low-temperature exhaust gas and second electric energy, wherein the parameters of the low-temperature exhaust gas are: temperature 50-60°C, pressure 0.1Mpa, CO content less than 3%,

[0089] During the entire slag treatment process, the induced draft device 70 is in working condition and introduces the gas in the connecting pipeline into the corresponding high-heat waste gas recycling device 30 and the low-heat waste gas recycling device 50; the induced draft device 70 is arranged on the connecting pipeline to regulate the flow rate and flow direction of the gas in the connecting pipeline; the connecting pipeline includes a first connecting pipeline 40 and a second connecting pipeline 60, the first connecting pipeline 40 is used to connect the blast furnace slag tempering device 10 with the high-heat waste gas recycling device 30, and the second connecting pipeline 60 is used to connect the high-heat waste gas recycling device 30 with the low-heat waste gas recycling device.

[0090] The foregoing description of specific exemplary embodiments of the present invention is for the purpose of illustration and demonstration. These descriptions are not intended to limit the present invention to the precise form disclosed, and it is clear that many changes and variations can be made based on the above teachings. The purpose of selecting and describing the exemplary embodiments is to explain the specific principles of the present invention and its practical application, so that those skilled in the art can realize and utilize various different exemplary embodiments of the present invention and various different selections and changes. The scope of the present invention is intended to be limited by the claims and their equivalents.

Claims

1. A blast furnace slag tempering method, characterized in that: include: Adding a tempering agent to liquid blast furnace slag, wherein the tempering agent is rich in SiO2 and Al2O3; The weight ratio of the liquid blast furnace slag to the tempering agent is 85-95:5-15.

2. The blast furnace slag tempering method according to claim 1, characterized in that: The conditioning agent is waste material from the steel production process, preferably, the conditioning agent is iron ore waste rock and / or fly ash; and / or, the particle size of the conditioning agent is below 100 μm; And / or, after adding the conditioning agent, the acidity of the liquid blast furnace slag is 1.2-1.4, the viscosity is 1-3 Pa·s, and the temperature is 1350-1400°C.

3. A blast furnace slag tempering device, characterized in that: include: The main body has a tempering area inside for the liquid blast furnace slag to react with the tempering agent to generate modified slag and high-heat exhaust gas; A liquid blast furnace slag introduction portion is provided on the main body portion and is used to introduce liquid blast furnace slag into the tempering area of ​​the main body portion; A conditioning agent spraying portion, disposed on the main body portion, for spraying the conditioning agent to the conditioning area of ​​the main body portion; The gas combustion part is arranged on the main body part and is used to provide a heat source to the tempering area of ​​the main body part.

4. The blast furnace slag tempering device according to claim 3, characterized in that: The main body includes: A tempering container, with an opening at the top and a discharge port at the bottom, wherein the tempering container has a tempering area for reacting liquid blast furnace slag with a tempering agent to generate reformed slag and high-temperature exhaust gas; The gas collecting hood covering the top opening area of ​​the conditioning container is arranged at the top opening of the conditioning container.

5. The blast furnace slag tempering device according to claim 4, characterized in that: The liquid blast-furnace slag introduction part is arranged on the tempering container or the gas collecting hood, and is used to introduce liquid blast-furnace slag into the tempering area.

6. The blast furnace slag tempering device according to claim 4, characterized in that: The conditioning agent injection part is arranged on the side wall of the conditioning container and is used to inject the conditioning agent into the conditioning area; The conditioning agent injection parts are provided with a plurality of groups, and preferably, the conditioning agent injection parts are provided with 2 groups.

7. The blast furnace slag tempering device according to claim 4, characterized in that: The gas combustion part is arranged on the gas collecting hood and is used to provide a heat source to the tempering area.

8. The blast furnace slag tempering device according to claim 3, characterized in that: The conditioning agent injection part comprises a main spray gun and a branch spray gun, wherein the main spray gun is arranged on the upper part of the branch spray gun, and the branch spray gun is provided in a plurality of groups.

9. A method for treating blast furnace slag based on the blast furnace slag tempering device according to any one of claims 3 to 8, characterized in that: include: Introducing liquid blast furnace slag into a tempering container, and adding a tempering agent into the tempering container through a main spray gun and a branch spray gun, wherein the weight ratio of the liquid slag to the tempering agent is 85-95:5-15; The liquid blast furnace slag and the tempering agent mixture are sprayed and heated to 1350-1400°C through the gas combustion section for 30-60 minutes.

10. The blast furnace slag treatment method according to claim 9, characterized in that: After adding the conditioning agent, the acidity of the liquid blast furnace slag is 1.2-1.4, and the viscosity is 1-3 Pa·s; And / or, the spraying pressure of the main spray gun is 0.3-1.0Mpa, and the spraying pressure of the branch spray gun is 0.3-0.8Mpa; And / or, the injection pressure of the gas combustion part is 0.3-0.7Mpa, and the CO content in the furnace is controlled to be less than 3% during the injection process.

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