Waste-free blast furnace slag treatment equipment and method

Abstract

The invention discloses waste-free blast furnace slag treatment equipment and method, and the waste-free blast furnace slag treatment equipment comprises a tempering device for reacting liquid blast furnace slag with a tempering agent to generate modified slag and high-heat waste gas, and a modified slag processing device for receiving the modified slag and processing the modified slag into slag wool boards, the first waste heat power generation device is used for converting the high-heat waste gas into low-heat waste gas and first electric energy; the first connecting pipeline is used for communicating the tempering device with the first waste heat power generation device; the second waste heat power generation device is used for converting the low-heat waste gas into low-temperature waste gas and second electric energy; the second connecting pipeline is used for communicating the first waste heat power generation device with the second waste heat power generation device; and the air inducing device is used for providing gas flow gravitation in the slag treatment equipment. The blast furnace slag is reprocessed into the slag wool board, meanwhile, the two-stage waste heat power generation device is used for fully utilizing high-temperature flue gas for power generation, and maximum utilization of the blast furnace slag can be achieved.

Description

Technical Field

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

[0002] The blast furnace slag treatment process is divided into dry method and wet method. The wet method is the water quenching method, which is a blast furnace slag treatment process in which the molten blast furnace slag is poured into water for rapid cooling and granulated under the action of thermal stress. The current water quenching methods include the Lhasa method (RASA), the Tula method (TYNA), the Minter method (MTC), the bottom filtration method (OCP), and the Inba method (INBA). The wet blast furnace slag treatment process consumes a large amount of water resources to ensure that the slag is in full contact with water. At the same time, in the process of contact with the high-temperature slag, a large amount of water evaporates and dissipates, and the waste heat generated is mostly low-temperature waste heat below 100°C, with low energy density, great difficulty in recovery, and dispersed heat distribution, which increases the recovery cost. Due to the cost and system complexity, the waste heat utilization of wet slag treatment systems often remains in low-end areas such as heating, and a large amount of waste heat is wasted; the blast furnace dry slag treatment process is a blast furnace slag treatment process that utilizes direct contact and heat exchange between air and high-temperature slag, including the drum method and the centrifugal method, but no matter which method is used, large-scale professional equipment is required, the equipment is complex, the equipment maintenance requirements are high, and there is serious loss in daily operation. At the same time, the quality of the slag after treatment is unstable, and it is difficult to meet the subsequent resource utilization needs. Therefore, although the waste heat source of the dry slag treatment process is concentrated, the heat is difficult to fully utilize, and no good recovery plan has been proposed.

[0003] 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

[0004] In order to solve the technical problem that the by-products obtained by the slag treatment process in the prior art have low added value, which not only cannot fully realize the comprehensive utilization of resources but also produces a large amount of industrial solid waste, a waste-free blast furnace slag treatment equipment and method are provided.

[0005] In a first aspect, the present invention provides a waste-free blast furnace slag treatment device, comprising:

[0006] A tempering device, used to react liquid blast furnace slag with a tempering agent to generate modified slag and high-temperature exhaust gas;

[0007] A modified slag processing device, used for processing the modified slag into a slag wool board;

[0008] a first waste heat power generation device, used for converting the high-heat exhaust gas generated by the quenching and tempering device into low-heat exhaust gas and first electric energy;

[0009] a second waste heat power generation device, used for converting the low-heat exhaust gas generated by the first waste heat power generation device into low-temperature exhaust gas and second electric energy;

[0010] a connecting pipeline, comprising a first connecting pipeline and a second connecting pipeline; the first connecting pipeline is used to connect the quenching and tempering device with the first waste heat power generation device; the second connecting pipeline is used to connect the first waste heat power generation device with the second waste heat power generation device; and

[0011] The air inducing device is arranged on the connecting pipeline and is used to adjust the flow rate and flow direction of the gas in the connecting pipeline.

[0012] In certain embodiments, the tempering device comprises:

[0013] A slag ditch, used to introduce liquid blast furnace slag into the interior of the quenching and tempering device;

[0014] A first spray gun, the nozzle of which is arranged inside the quenching and tempering device and is used to spray the quenching and tempering agent into the quenching and tempering device;

[0015] An air collecting hood is arranged on the top of the quenching and tempering device and is connected to the first connecting pipeline;

[0016] A valve, arranged at the discharge port at the lower part of the quenching and tempering device, is used to control the switch of the discharge port of the quenching and tempering device;

[0017] A flow meter is arranged at the discharge port at the bottom of the quenching and tempering device, and is used to detect the flow rate at the discharge port of the quenching and tempering device;

[0018] The second spray gun has a nozzle disposed inside the quenching and tempering device and is used for spraying industrial fuel gas into the quenching and tempering device.

[0019] In some embodiments, the temperature of the industrial fuel gas sprayed by the second spray gun of the tempering device is not less than 1400°C, and the spraying carrier of the second spray gun of the tempering device includes compressed air with an oxygen-enriched content in the range of 1% to 3%, so as to control the reaction temperature in the tempering device and the CO content in the tempering device.

[0020] In some embodiments, the modified slag processing device comprises:

[0021] A fiber-forming device, used for processing the modified slag generated by the quenching and tempering device into slag cotton yarn; and

[0022] The curing and forming device is used for curing the slag wool filaments generated by the fiber forming device into a slag wool board by reacting with a binder.

[0023] In some embodiments, the first waste heat power generation device includes:

[0024] A first waste heat boiler is connected to the tempering device through a first connecting pipeline, and is used to convert the high-temperature exhaust gas generated by the tempering device and the distilled water in the first waste heat boiler into superheated saturated steam; and

[0025] The first generator set is used to convert the superheated saturated steam generated by the first waste heat boiler into first electrical energy, low-heat exhaust gas and distilled water condensed and refluxed into the first waste heat boiler.

[0026] In some embodiments, the second waste heat power generation device comprises:

[0027] a second waste heat boiler, connected to the first waste heat power generation device through a second connecting pipeline, and used for converting the low-heat exhaust gas generated by the first waste heat power generation device and the distilled water in the second waste heat boiler into saturated steam by superheating; and

[0028] The second generator set is used to convert the saturated steam generated by the second waste heat boiler into second electric energy, low-temperature exhaust gas and distilled water condensed and refluxed into the first waste heat boiler.

[0029] In certain embodiments, the slag treatment equipment further includes a desulfurization recovery device connected to the second connecting pipeline, the desulfurization recovery device is used to desulfurize the low-heat exhaust gas generated by the first waste heat power generation device and recover the dust generated after desulfurization.

[0030] In some embodiments, the induced draft device is also used to introduce the low-temperature exhaust gas generated by the second waste heat power generation device into the first spray gun in the tempering device as a spraying carrier.

[0031] In a second aspect, a method for treating waste-free blast furnace slag is provided, the slag treatment method comprising the following steps:

[0032] First, a tempering device is used to react liquid blast furnace slag with a tempering agent to generate modified slag and high-heat exhaust gas;

[0033] Then, a modified slag processing device is used to receive the modified slag in the quenching and tempering device, and the modified slag in the quenching and tempering device is processed into a slag wool board;

[0034] Then, the first waste heat power generation device receives the high-heat exhaust gas generated by the quenching and tempering device through the first connecting pipeline and converts the high-heat exhaust gas into low-heat exhaust gas and the first electric energy;

[0035] Finally, the second waste heat power generation device receives the low-heat exhaust gas generated by the first waste heat power generation device through the second connecting pipeline and converts the low-heat exhaust gas into low-temperature exhaust gas and second electric energy;

[0036] During the entire slag treatment process, the induced draft device is in working condition and introduces the gas in the connecting pipeline into the corresponding first waste heat power generation device and the second waste heat power generation device; the induced draft device is arranged on the connecting pipeline, and is used to regulate the flow rate and flow direction of the gas in the connecting pipeline; the connecting pipeline includes a first connecting pipeline and a second connecting pipeline, the first connecting pipeline is used to connect the tempering device with the first waste heat power generation device, and the second connecting pipeline is used to connect the first waste heat power generation device with the second waste heat power generation device.

[0037] Compared with the prior art, the technical effects achieved by the present invention are as follows:

[0038] The present invention integrates the design of blast furnace slag reprocessing technology and high-temperature flue gas waste heat utilization. While reprocessing blast furnace slag into slag wool board, a two-stage waste heat power generation device is used to fully utilize the waste heat generated by the reaction to generate electricity, thereby maximizing the utilization of blast furnace slag resources. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 is a work flow chart of a slag treatment device provided in one embodiment of the present invention;

[0040] Figure 2 It is a schematic structural diagram of a tempering device in a slag treatment equipment provided in one embodiment of the present invention. DETAILED DESCRIPTION

[0041] 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.

[0042] 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.

[0043] Example:

[0044] like Figure 1 As shown, a slag treatment device is provided, including: a tempering device 10, a modified slag processing device 20, a first waste heat power generation device 30, a second waste heat power generation device 50 and a connecting pipeline.

[0045] The tempering device 10 is used to react liquid blast furnace slag 801 with a tempering agent 802 to generate reformed slag 804 and high-temperature exhaust gas 901.

[0046] The modified slag processing device 20 is used to process the modified slag in the quenching and tempering device 10 into a slag wool board. In some embodiments, the modified slag processing device 20 is connected to the quenching and tempering device 10.

[0047] The connecting pipeline includes a first connecting pipeline 40 and a second connecting pipeline 60;

[0048] The two ends of the first connecting pipeline 40 are respectively connected to the quenching and tempering device 10 and the first waste heat power generation device 30, so as to connect the quenching and tempering device 10 with the first waste heat power generation device 30, so that the high-heat exhaust gas generated by the quenching and tempering device 10 can be transported to the first waste heat power generation device 30 through the first connecting pipeline 40, and the first waste heat power generation device 30 is used to convert the received high-heat exhaust gas generated by the quenching and tempering device 10 into low-heat exhaust gas and first electric energy;

[0049] The two ends of the second connecting pipeline 60 are respectively connected to the first waste heat power generation device 30 and the second waste heat power generation device 50, so as to connect the first waste heat power generation device 30 with the second waste heat power generation device 50, so that the low-heat exhaust gas generated by the first waste heat power generation device 30 is transported to the second waste heat power generation device 50 through the second connecting pipeline 60, and the second waste heat power generation device 50 is used to convert the received low-heat exhaust gas generated by the first waste heat power generation device 30 into low-temperature exhaust gas and second electric energy.

[0050] 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.

[0051] When the slag treatment equipment is working, the 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 tempering device 10, and the modified slag 804 in the tempering device 10 is processed into a slag wool board, and then the first waste heat power generation device 30 receives the high-heat waste gas generated by the 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, and finally the second waste heat power generation device 50 receives the low-heat waste gas generated by the first waste heat power generation device 30 through the second connecting pipeline 60 and converts the low-heat waste gas into low-temperature waste gas and the second electric energy. In this process, the induced draft device 70 is in working state and introduces the gas in the connecting pipeline into the corresponding first waste heat power generation device 30 and the second waste heat power generation device 50.

[0052] like Figure 2As shown, in one embodiment, the tempering device 10 includes a slag ditch 101, a first spray gun 102, a gas collecting hood 103, a valve 1041 and a flow meter 1042, a second spray gun 105 and a tempering container 107.

[0053] Among them, 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, high pressure and impact, wear and erosion of internal materials. In some embodiments, 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 performance, 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 supporting part 108 is usually composed of a bracket, a base, anchor bolts and other components, and its structure and strength should be adjusted according to the weight, size and vibration of the tempering device 10 during operation.

[0054] The gas collecting hood 103 is installed at the opening of the upper part of the conditioning container 107, and serves as the top sealing component of the conditioning container 107, and is used to collect the high-temperature exhaust gas discharged from the conditioning container 107, and collect the high-temperature exhaust gas while preventing 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] The slag groove 101 is inserted on the side wall of the gas collecting hood 103 or the side wall of the quenching and tempering container 107, and 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] 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; 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; in some embodiments, the main spray gun 1021 The blowing pressure 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 temper the liquid blast furnace slag so that the composition of the liquid blast furnace slag meets 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] The second spray gun 105 is inserted on the top wall of the gas collecting hood 103 (in one embodiment, the top wall of the gas collecting hood 103 has a hole, and the second spray gun 105 is roughly inserted on the top wall of the gas collecting hood 103), and its nozzle (the lower end of the second spray gun 105) is located just 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, the second spray gun 105 is inserted on the top wall of the gas collecting hood 103, and the second spray gun 105 is inserted on the top wall of the gas collecting hood 103. 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] A valve 1041 and a flow meter 1042 are installed at the discharge port 104 of the quenching and tempering device 10 . The valve 1041 is used to control the switch of the discharge port 104 of the quenching and tempering device 10 , and the flow meter 1042 is used to detect the flow at the discharge port 104 of the valve 1041 .

[0059] Working principle of quenching and 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 iron and steel production process wastes rich in SiO2 and Al2O3, preferably, the SiO2 content is 30%-80%, and the Al2O3 content is 5%- 40%) is sprayed into the tempering container 107 through the first spray gun 102, the weight ratio of liquid blast furnace slag 801 to tempering agent 802 is 85-95:5-15, 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 requires maintenance. To ensure that the temperature of the reformed slag 804 is maintained at 1350-1400°C, the second spray gun 105 is required 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°C, 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 in to supplement the heat. The theoretical combustion temperature of converter gas is 1600-1800°C, and the theoretical combustion temperature of coke oven gas is 1900-2100°C. During the spraying process, the furnace is controlled The CO content is less than 3% (the CO content exceeding 3% will affect the 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 it cannot be solved, the industrial gas can be fully burned by enriching the compressed air with 1-3% oxygen 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 first waste heat power generation device 30 through the first connecting pipeline 40.

[0061] (II) After the blast furnace slag tapping 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 reformed 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 1-3 Pa·s (if the spraying time is too short, the tempering agent 802 will not be completely melted, and if it is too long, it will cause energy waste; if the reformed slag 804 is sticky, it will cause the slag to be sludged and the slag will be sludged. The acidity 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 slag must be centrifuged after modification. If it is not within this range, the centrifugation will not be good and the next step cannot be carried out. If the acidity and viscosity exceed the above range, it will result in long centrifugal fibers, while if the acidity and viscosity are lower than the above range, it will result in short centrifugal fibers). The spraying of the tempering agent 802 and the industrial gas 803 is ended, and the liquid blast furnace slag 801 is converted into modified slag 804 after tempering. The valve 1041 at the discharge port of the tempering container 107 is opened, and the modified slag 804 is added to the fiber-forming device 201 for centrifugal cotton processing. 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 1 As shown, in one embodiment, the modified slag processing device 20 includes a fiber-forming device 201 and a solidification and molding device 202 .

[0063] The fiber-forming device 201 is used to process the modified slag 804 generated by the quenching and 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.

[0064] 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.

[0065] Working principle of the modified slag processing device 20: The modified 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.

[0066] like Figure 1 As shown, in one embodiment, the first waste heat power generation 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 tempering device 10 through a first connecting pipeline 40, and is used to superheat the high-heat exhaust gas 901 generated by the tempering device 10 and the distilled water inside the first waste heat boiler 301 and convert it into superheated saturated steam 902; 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 exhaust 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.

[0067] 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 first waste heat power generation 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 first waste heat power generation 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.

[0068] In one embodiment, a denitrification point is provided inside the first waste heat boiler 301 in the first waste heat power generation 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 ammonia gas, ammonia water, urea and other substances, which can eliminate nitrogen oxides in the exhaust gas.

[0069] like Figure 1 As shown, in one embodiment, the slag treatment equipment also includes a desulfurization recovery device 100 connected to the second connecting pipeline 60, and the desulfurization recovery device 100 is used to desulfurize the low-heat exhaust gas 904 generated by the first waste heat power generation device 30 to obtain a low-heat exhaust gas 904 with a temperature of 140-200°C, a pressure of 0.1Mpa, and CO% <3%, and recover the dust generated after desulfurization.

[0070] Specifically, the first waste heat power generation 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.

[0071] like Figure 1 As shown, in one embodiment, the second waste heat power generation 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 first waste heat power generation device 30 through a second connecting pipeline 60, and is used to convert the low-heat exhaust gas 904 generated by the first waste heat power generation device 30 and the distilled water inside the second waste heat boiler 501 into saturated steam 905 (the 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 to the first waste heat boiler 301. In one embodiment, the second generator set 502 is an ORC generator set.

[0072] 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 second waste heat power generation 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 second waste heat power generation 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 gaseous state. The high-temperature and high-pressure gaseous organic working medium enters the expander of the second generator set 502 in the second waste heat power generation device 50 and expands inside it, thereby driving the rotor of the expander of the second generator set 502 in the second waste heat power generation device 50 to rotate. The expander of the second generator set 502 in the second waste heat power generation 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.

[0073] The second waste heat power generation device 50 outputs the second electric energy 906 and converts the low-heat exhaust gas 904 with a temperature of 140°C-200°C into a low-temperature exhaust gas 907 with a temperature of 50-60°C. The exhaust gas in this state has no economic utilization value and meets the environmental emission requirements. Finally, the low-temperature exhaust gas 907 in the second waste heat power generation device 50 is discharged from the exhaust 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 quenching and tempering device 10, so as to realize the internal circulation of the gas in the system.

[0074] 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 parameters of the low-temperature exhaust gas are: temperature 50-60°C, pressure 0.1Mpa, CO content less than 3%), the investment cost is high and the process difficulty is relatively large. Therefore, two sets of waste heat power generation devices are set up for 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.

[0075] like Figure 1 As shown, in one embodiment, the induced draft device 70 is also used to introduce the low-temperature exhaust gas 907 generated by the second waste heat power generation device 50 into the first spray gun 102 in the tempering device 10 as a spraying carrier.

[0076] In some implementations, the present invention provides a slag treatment method, which is based on a slag treatment device, and the specific steps are as follows:

[0077] First, a tempering device 10 is used to react liquid blast furnace slag 801 with a tempering agent 802 to generate reformed slag 804 and high-temperature exhaust gas 901;

[0078] Then, the modified slag processing device 20 is used to receive the modified slag 804 in the quenching and tempering device 10, and the modified slag 804 in the quenching and tempering device 10 is processed into a slag wool board;

[0079] Then, the first waste heat power generation device 30 receives the high-heat exhaust gas generated by the quenching and tempering device 10 through the first connecting pipeline 40 and converts the high-heat exhaust gas into low-heat exhaust gas and the first electric energy;

[0080] Finally, the second waste heat power generation device 50 receives the low-heat exhaust gas generated by the first waste heat power generation device 30 through the second connecting pipeline 60 and converts the low-heat exhaust gas into low-temperature exhaust gas and second electric energy;

[0081] 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 first waste heat power generation device 30 and the second waste heat power generation device 50; the induced draft device 70 is arranged on the connecting pipeline, and is used 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 tempering device 10 with the first waste heat power generation device 30, and the second connecting pipeline 60 is used to connect the first waste heat power generation device 30 with the second waste heat power generation device 50.

[0082] 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 waste-free blast furnace slag treatment equipment, characterized in that: include: A tempering device, used to react liquid blast furnace slag with a tempering agent to generate modified slag and high-temperature exhaust gas; A modified slag processing device, used for processing the modified slag into a slag wool board; a first waste heat power generation device, used for converting the high-heat exhaust gas generated by the quenching and tempering device into low-heat exhaust gas and first electric energy; a second waste heat power generation device, used for converting the low-heat exhaust gas generated by the first waste heat power generation device into low-temperature exhaust gas and second electric energy; A connecting pipeline, comprising a first connecting pipeline and a second connecting pipeline; the first connecting pipeline is used to connect the quenching and tempering device with the first waste heat power generation device; the second connecting pipeline is used to connect the first waste heat power generation device with the second waste heat power generation device; The air inducing device is arranged on the connecting pipeline and is used to adjust the flow rate and flow direction of the gas in the connecting pipeline.

2. The waste-free blast furnace slag treatment equipment according to claim 1, characterized in that: The quenching and tempering device comprises: a slag ditch for introducing liquid blast furnace slag into the interior of the quenching and tempering device; a first spray gun, the nozzle of which is arranged inside the quenching and tempering device and is used to spray the conditioning agent into the interior of the quenching and tempering device; An air collecting hood is arranged on the top of the conditioning device and is connected to the first connecting pipeline; A valve, arranged at the discharge port at the lower part of the quenching and tempering device, for controlling the switch of the discharge port of the quenching and tempering device; A flow meter, arranged at the discharge port at the bottom of the quenching and tempering device, for detecting the flow at the discharge port of the quenching and tempering device; The second spray gun has a nozzle disposed inside the quenching and tempering device and is used for spraying industrial gas into the interior of the quenching and tempering device.

3. The waste-free blast furnace slag treatment equipment according to claim 1, characterized in that: The modified slag processing device comprises: a fiber-forming device, used for processing the modified slag generated by the quenching and tempering device into slag cotton yarn; and The curing and forming device is used for curing the slag wool filaments generated by the fiber-forming device with a binder to form a slag wool board.

4. The waste-free blast furnace slag treatment equipment according to claim 1, characterized in that: The first waste heat power generation device comprises: a first waste heat boiler, connected to the tempering device through the first connecting pipeline, and used for converting the high-temperature exhaust gas generated by the tempering device and the distilled water inside the first waste heat boiler into superheated saturated steam; The first generator set is used to convert the superheated saturated steam generated by the first waste heat boiler into first electrical energy, low-heat exhaust gas, and distilled water condensed and refluxed into the first waste heat boiler.

5. The waste-free blast furnace slag treatment equipment according to claim 4, characterized in that: The first generator set is a steam turbine generator set.

6. The waste-free blast furnace slag treatment equipment according to claim 4, characterized in that: The second waste heat power generation device comprises: a second waste heat boiler, connected to the first waste heat power generation device through the second connecting pipeline, and used for converting the low-heat exhaust gas generated by the first waste heat power generation device and the distilled water in the second waste heat boiler into saturated steam by superheating; and The second generator set is used to convert the saturated steam generated by the second waste heat boiler into second electric energy, low-temperature exhaust gas and distilled water condensed and refluxed into the first waste heat boiler.

7. The waste-free blast furnace slag treatment equipment according to claim 6, characterized in that: The second generator set is an ORC generator set.

8. The waste-free blast furnace slag treatment equipment according to claim 1, characterized in that: The slag treatment equipment also includes a desulfurization recovery device connected to the second connecting pipeline, and the desulfurization recovery device is used to desulfurize the low-heat exhaust gas generated by the first waste heat power generation device and recover the dust generated after desulfurization.

9. The waste-free blast furnace slag treatment equipment according to claim 2, characterized in that: The induced draft device is also used to introduce the low-temperature exhaust gas generated by the second waste heat power generation device into the first spray gun in the tempering device as a spraying carrier.

10. A method for treating waste-free blast furnace slag, characterized in that: Based on the slag treatment equipment according to any one of claims 1 to 9, the slag treatment method comprises the following steps: First, a tempering device is used to react liquid blast furnace slag with a tempering agent to generate modified slag and high-heat exhaust gas; Then, a modified slag processing device is used to receive the modified slag in the quenching and tempering device, and the modified slag in the quenching and tempering device is processed into a slag wool board; Then, the first waste heat power generation device receives the high-heat exhaust gas generated by the quenching and tempering device through the first connecting pipeline and converts the high-heat exhaust gas into low-heat exhaust gas and the first electric energy; Finally, the second waste heat power generation device receives the low-heat exhaust gas generated by the first waste heat power generation device through the second connecting pipeline and converts the low-heat exhaust gas into low-temperature exhaust gas and second electric energy; During the entire slag treatment process, the induced draft device is in working condition and introduces the gas in the connecting pipeline into the corresponding first waste heat power generation device and the second waste heat power generation device; the induced draft device is arranged on the connecting pipeline, and is used to regulate the flow rate and flow direction of the gas in the connecting pipeline; the connecting pipeline includes a first connecting pipeline and a second connecting pipeline, the first connecting pipeline is used to connect the tempering device with the first waste heat power generation device, and the second connecting pipeline is used to connect the first waste heat power generation device with the second waste heat power generation device.

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