Coal gangue activation calcining equipment and calcining method

Abstract

The invention relates to the technical field of mineral calcining equipment and processes, in particular to coal gangue activation calcining equipment and a calcining method.The calcining equipment comprises a hot blast stove and an activation reactor, the hot blast stove is provided with a combustion cavity, and the combustion cavity is used for generating high-temperature flue gas or introducing hot air; the activation reactor penetrates through the combustion cavity from the upper portion of the hot blast stove to the lower portion of the hot blast stove, the upper end of the activation reactor is a feeding end, the lower end of the activation reactor is a discharging end, and a material cavity is formed in the activation reactor and used for containing coal gangue. Hot air in the combustion cavity is transferred to the coal gangue in the material cavity through the side wall of the activation reactor, so that the coal gangue is subjected to low-oxygen or anaerobic calcination in the material cavity. According to the calcining equipment, indirect calcining is achieved through partition wall heating of the side walls, and the material cavity and the combustion cavity are completely isolated to create an anaerobic or low-oxygen calcining environment. The aluminum-silicon ratio of the coal gangue calcined by the calcining method is greatly increased, the crystal form transformation effect is remarkable, and volatile component recovery, heat-conducting sphere cyclic utilization and waste heat preheating are realized.

Description

Technical Field

[0001] This application relates to the field of mineral calcination equipment and process technology, and in particular to a coal gangue activation calcination equipment and calcination method. Background Technology

[0002] Coal gangue is a general industrial solid waste generated during coal mining and excavation. Its large-scale stockpiling not only occupies land resources but also easily causes serious environmental pollution, making it a large-scale solid waste requiring comprehensive utilization. Currently, the resource utilization of coal gangue is mostly concentrated in low-value-added areas such as pit filling, road construction, and sintered brick production. In terms of high-value utilization, extracting valuable metals such as aluminum, silicon, gallium, and germanium has become an important development direction. A key prerequisite for achieving this goal is to perform high-temperature activation and calcination of the coal gangue, causing a crystal transformation of the aluminum and silicon compounds and improving the aluminum-silicon separation efficiency.

[0003] Coal gangue contains volatile matter and fixed carbon. Existing calcination equipment, such as rotary kilns, tunnel kilns, and suspension kilns, cannot avoid the heat release from the combustion of volatile matter and fixed carbon during the calcination process, which can easily lead to uncontrolled temperature of coal gangue particles, resulting in overburning or deactivation. At the same time, existing equipment is difficult to achieve precise temperature control during the calcination process and cannot stably complete the crystal transformation of coal gangue. To date, there is no mature equipment and process that meets the industrial requirements for efficient aluminum-silicon separation through activated calcination of coal gangue. Summary of the Invention

[0004] This application provides a coal gangue activation and calcination equipment and method to solve the problems of runaway calcination temperature, poor crystal transformation effect, and low equipment adaptability in the prior art. It provides a coal gangue activation and calcination equipment and method to achieve precise calcination of coal gangue in an oxygen-free or low-oxygen environment, effectively control the calcination temperature and time, ensure stable crystal transformation of coal gangue, and improve calcination efficiency and energy utilization.

[0005] On the one hand, this application provides a coal gangue activation and calcination device, comprising: A hot air furnace has a combustion chamber, which is used to generate high-temperature flue gas or to introduce hot air. The activation reactor extends from the top of the hot blast stove through the combustion chamber to the bottom of the hot blast stove. The upper end of the activation reactor is the feed end, and the lower end is the discharge end. A material chamber is formed in the activation reactor, which is used to load coal gangue. Hot air in the combustion chamber is transferred to the coal gangue in the material chamber through the side wall of the activated reactor, so that the coal gangue can be calcined in the material chamber under low oxygen or oxygen-free conditions.

[0006] In one possible design, multiple air guide holes are spaced apart on the sidewall of the activation reactor to guide the volatile gases in the material chamber into the combustion chamber.

[0007] In one possible design, an air guide portion extending into the combustion chamber is formed on the outer wall of the activation reactor at the air guide hole, with the air guide hole extending along the length of the air guide portion.

[0008] In one possible design, a valve is installed at the discharge end of the activation reactor, and the valve can adjust the falling speed of coal gangue in the material chamber by adjusting the opening degree.

[0009] In one possible design, a heat-conducting sphere is also included. The heat-conducting sphere is mixed with coal gangue and placed in the activation reactor. The heat-conducting sphere is used to transfer heat from the inner wall of the activation reactor to the material chamber.

[0010] In one possible design, the thermally conductive sphere is made of alumina or silicon carbide. And / or, the diameter of the thermally conductive sphere is 1 to 20 mm.

[0011] In one possible design, a screen is also included, which is positioned below the discharge end of the activation reactor; And / or, it also includes a cooling zone located below the discharge end of the activation reactor.

[0012] In one possible design, one end of the hot blast stove is connected to the burner, and the other end has an air outlet. A thermocouple is installed inside the hot blast stove.

[0013] On the other hand, this application also provides a method for activating and calcining coal gangue, using the above-mentioned coal gangue activation and calcination equipment, and the calcination method includes: Coal gangue is added to the material chamber from the feed end of the self-activation reactor. The coal gangue in the material chamber is isolated from the high-temperature flue gas or hot air in the combustion chamber of the hot blast stove. The coal gangue is in an oxygen-free or low-oxygen environment in the activation reactor. The high-temperature flue gas or hot air in the combustion chamber is used to heat and activate the reactor. The heat from the activation reactor is transferred to the material chamber. As the coal gangue moves down in the material chamber, it gradually heats up until it reaches the preset calcination temperature. Coal gangue descends in the material chamber for a preset calcination time to complete material decomposition and crystal transformation; The volatile gases generated during the calcination of coal gangue are introduced into the combustion chamber for combustion through the gas guide hole; After calcination, the coal gangue is discharged from the outlet of the activated reactor.

[0014] In one possible design, the preset calcination time is 1-40 hours; And / or, the preset calcination temperature is 900-1150℃.

[0015] The beneficial effects of this application are as follows: The coal gangue activation and calcination equipment disclosed in this application employs a hot blast stove and an activation reactor, achieving indirect calcination through sidewall heating. The material chamber and combustion chamber are completely isolated, creating an oxygen-free or low-oxygen calcination environment. Simultaneously, the vent holes discharge residual oxygen along with volatiles during the initial calcination stage, further reducing the oxygen content. This fundamentally avoids temperature runaway caused by the combustion heat release of fixed carbon and volatiles in the coal gangue, preventing over-burning or deactivation of the material. During subsequent calcination, the vent holes guide volatiles into the hot blast stove combustion chamber for recycling, supplementing the hot blast stove's heat source, reducing burner fuel consumption, and improving energy utilization.

[0016] The heat-conducting spheres can quickly transfer heat from the inner wall of the activation reactor to the center of the material cavity, solving the problem of uneven local temperature in the material during traditional calcination and ensuring a consistent overall crystal transformation of the coal gangue. Furthermore, the spherical structure increases the porosity in the material flow, reduces gas diffusion resistance, and, together with the air guide holes, enables the smooth discharge of volatiles and air. This optimizes the calcination environment and avoids problems such as poor material flow and cross-contamination caused by the accumulation of volatiles.

[0017] The coal gangue activation and calcination method provided in this application, by employing the coal gangue activation and calcination equipment described in this application, simultaneously incorporates all the aforementioned advantages of the equipment. The calcination method described in this application significantly increases the aluminum-silicon ratio of the calcined coal gangue, resulting in a remarkable crystal transformation effect. It also achieves volatile matter recovery, heat-conducting sphere recycling, and waste heat preheating, thus combining environmental friendliness, economy, and practicality. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the specific embodiments of this application or the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0019] Figure 1 A schematic diagram of the structure of the coal gangue activation and calcination equipment provided in the embodiments of this application; Figure label: 1. Hot air furnace; 11. Combustion chamber; 12. Air outlet; 2. Activation reactor; 21. Feeding end; 22. Discharge end; 23. Material chamber; 24. Air guide hole; 25. Air guide section; 3. Valve; 4. Burner; 5. Thermocouple. Detailed Implementation

[0020] The technical solutions of this application will be clearly and completely described below with reference to the embodiments. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0021] The following is combined Figure 1 This application describes a coal gangue activation and calcination device provided in an embodiment. The calcination device includes a hot blast stove 1 and an activation reactor 2. A combustion chamber 11 is formed inside the hot blast stove 1, which is used to generate high-temperature flue gas or introduce hot air to provide a heat source for coal gangue calcination. One end of the hot blast stove 1 is connected to a burner 4, which provides an initial heat source for the hot blast stove 1 and enables the regulation of the hot air temperature in the combustion chamber 11. The other end of the hot blast stove 1 has an air outlet 12 for discharging the waste gas inside the hot blast stove 1. A thermocouple 5 is installed inside the hot blast stove 1, which is used to monitor the hot air temperature inside the combustion chamber 11 in real time, providing data support for temperature regulation and achieving precise temperature control.

[0022] The activation reactor 2 extends from the top of the hot blast stove 1 through the combustion chamber 11 to the bottom of the hot blast stove 1. The upper end of the activation reactor 2 is the feed end 21, and the lower end is the discharge end 22. A material chamber 23 is formed in the activation reactor 2, which is used to load coal gangue. A valve 3 is provided at the discharge end 22 of the activation reactor 2. By adjusting the opening degree of the valve 3, the falling speed of the coal gangue in the material chamber 23 can be adjusted, thereby precisely controlling the residence time of the coal gangue in the calcination temperature zone and ensuring sufficient crystal transformation.

[0023] The number of activation reactors 2 includes multiple reactors, such as ten arranged in sequence. All activation reactors 2 are arranged in the combustion chamber 11 of the same hot blast stove 1, which can realize the large-scale calcination of coal gangue and greatly improve production efficiency.

[0024] Hot air in combustion chamber 11 is transferred through the side wall of activation reactor 2 to the coal gangue in each material chamber 23, raising the coal gangue to the calcination temperature. Because the coal gangue is isolated from the combustion furnace, very little air is introduced into the material chamber 23 through the material gaps, ensuring low-oxygen or oxygen-free calcination of the coal gangue in the material chamber 23. This ensures that the carbon in the coal gangue does not burn during calcination, preventing overburning or deactivation of the material.

[0025] In some embodiments, a plurality of air guide holes 24 are spaced apart on the sidewall of the activation reactor 2, which connect the material chamber 23 to the combustion chamber 11. Volatile gases are generated during the calcination of coal gangue. Firstly, the vent 24 can promptly discharge volatile gases, preventing them from burning and releasing heat in the material chamber 23, thus avoiding temperature runaway and preventing over-burning or deactivation of the material. Secondly, the timely discharge of volatile gases through the vent 24 effectively prevents their accumulation in the coal gangue, ensuring smooth flow of the coal gangue and effective calcination. Thirdly, when the coal gangue begins to calcine and generates volatile gases, these gases push a small amount of air out of the material chamber 23 and discharge it through the vent 24, further reducing the oxygen content in the material chamber 23 and ensuring a low-oxygen or oxygen-free calcination environment for the coal gangue. Fourthly, the volatile gases in the material chamber 23 are introduced into the combustion chamber 11 through the vent 24 to participate in combustion, achieving the recovery and reuse of volatile gases, supplementing the heat source for the hot blast stove 1, and reducing fuel consumption in the burner 4.

[0026] In some specific embodiments, a gas guide section 25 extending into the combustion chamber 11 is formed on the outer wall of the activation reactor 2 at the gas guide hole 24. The gas guide hole 24 extends along the length of the gas guide section 25, rapidly and directionally guiding the volatile gases and the propelled air to the combustion chamber 11, which is far from the outer wall of the activation reactor 2, for combustion. This prevents combustion from spreading through the gas guide hole 24 to the coal gangue on the inner wall of the activation reactor 2, thus preventing over-burning or deactivation of the material. At the same time, it improves the efficiency of gas guiding and oxygen removal, and prevents gas backflow.

[0027] In some specific embodiments, the device further includes thermally conductive spheres, which are mixed with coal gangue and then filled into the material chamber 23 of the activation reactor 2. Specifically, the thermally conductive spheres are made of alumina or silicon carbide, materials with excellent thermal conductivity, high temperature resistance, and stable chemical properties, making them suitable for the high-temperature calcination environment of coal gangue. The diameter of the thermally conductive spheres is 1-20 mm, matching the particle size of the coal gangue, ensuring both uniform heat transfer and maximizing material permeability. The thermally conductive spheres serve two purposes: firstly, they transfer heat from the inner wall of the activation reactor 2 to the material chamber 23, ensuring a uniform temperature distribution of the coal gangue within the material chamber 23, improving heat transfer efficiency, and avoiding localized temperature deviations; secondly, due to their spherical shape, the thermally conductive spheres enhance material permeability during material flow, reducing gas diffusion resistance and facilitating the smooth discharge of volatile gases and air from the air inlet 24 within the material chamber 23.

[0028] In some specific embodiments, the device also includes a screen located below the discharge end 22 of the activation reactor 2, for separating the calcined heat-conducting spheres from the coal gangue, thereby realizing the recycling of the heat-conducting spheres.

[0029] In some specific embodiments, the equipment also includes a cooling belt located below the discharge end 22 of the activation reactor 2, downstream of the screen. The calcined coal gangue is cooled by the cooling belt before being discharged, preventing the high-temperature material from contacting air and igniting. The calcined heat-conducting spheres are directly recycled without passing through the cooling belt and are used to mix with the coal gangue to be calcined for a new batch of calcination. The temperature of the heat-conducting spheres themselves can preheat the next batch of coal gangue to be calcined.

[0030] This application also provides a method for activating and calcining coal gangue, using the coal gangue activation and calcining equipment described in the above embodiments. The calcination method includes the following steps: A mixture of coal gangue and thermally conductive spheres is added to the material chamber 23 of the activation reactor 2. The coal gangue in the material chamber 23 is isolated from the high-temperature flue gas or hot air in the combustion chamber 11 of the hot blast stove 1, so that the coal gangue forms an initial low-oxygen or oxygen-free environment in the activation reactor 2 (the oxygen concentration in the low-oxygen environment is less than 1%), avoiding the temperature runaway caused by the combustion and heat release of fixed carbon and volatiles in the coal gangue.

[0031] The hot air in the combustion chamber 11 heats the activation reactor 2. The heat from the activation reactor 2 is transferred to the material chamber 23 through the side wall and the heat-conducting sphere. The coal gangue and the heat-conducting sphere gradually heat up as they descend in the material chamber 23 under their own gravity. In the initial stage of heating, the volatile gases produced by the coal gangue push the small amount of residual air in the material chamber 23 and discharge it to the combustion chamber 11 through the air guide hole 24, further reducing the oxygen content in the material chamber 23 and stabilizing the oxygen-free or low-oxygen calcination environment. The spherical heat-conducting sphere enhances the permeability of the material during flow, reduces the gas diffusion resistance, and ensures the smooth discharge of volatile gases and air. The coal gangue continues to heat up until the preset calcination temperature is reached.

[0032] Coal gangue descends to the preset calcination temperature zone in the material chamber 23 for a preset calcination time to complete material decomposition and crystal transformation; at the same time, the volatile gases continuously generated during the calcination of coal gangue are introduced into the combustion chamber 11 through the gas guide hole 24 for combustion, supplementing heat to the hot blast stove 1 and realizing energy recovery.

[0033] After calcination, the coal gangue is discharged from the discharge end 22 of the activation reactor 2, completing the calcination process.

[0034] The calcination method includes two feeding modes: continuous feeding mode and non-continuous feeding mode. The continuous feeding mode involves continuous addition, while the non-continuous feeding mode involves batch addition.

[0035] A detailed explanation will be provided using the continuous feeding mode as an example: Granular coal gangue with a particle size of 1-20 mm is mixed with alumina thermally conductive spheres at a mass ratio of 1:2. The mixture is continuously added to the material chamber 23 from the feed end 21 of the activation reactor 2, while the calcined material is continuously discharged from the discharge end 22. This ensures that the material chamber 23 is always filled with the mixture, and the mixture in the material chamber 23 is completely isolated from the high-temperature flue gas or hot air in the combustion chamber 11, forming an initial oxygen-free environment.

[0036] Burner 4 continuously supplies high-temperature flue gas into the combustion chamber 11 of hot blast stove 1. The flue gas temperature is monitored and controlled by thermocouple 5 and maintained at 1050-1250℃. The hot flue gas transfers heat to the material chamber 23 through the side wall of the activation reactor 2. The heat-conducting sphere rapidly transfers heat from the inner wall to the material chamber 23. At the same time, the spherical heat-conducting sphere enhances permeability and reduces gas diffusion resistance during material flow. As the coal gangue descends in the material chamber 23 under its own gravity, it gradually heats up. The volatile gases generated in the early stage of heating push the small amount of air remaining in the material chamber 23 and smoothly discharge it into the combustion chamber 11 through the air guide hole 24 and the air guide section 25, further ensuring that the material chamber 23 is an oxygen-free environment. The coal gangue continues to heat up and eventually reaches the preset calcination temperature of 1050℃.

[0037] Adjust the opening of valve 3 at the discharge end 22 so that the preset calcination time of the coal gangue in the 1050℃ calcination temperature zone of the material chamber 23 is 1.5h. During this process, the kaolinite in the coal gangue undergoes dehydroxylation and crystal transformation to generate metakaolinite, which is further decomposed into amorphous SiO2 and γ-Al2O3. The moisture, volatile matter and other gases continuously generated during the calcination process are introduced into the combustion chamber 11 through the gas guide hole 24 and the gas guide part 25 for combustion, which supplements the heat of the hot blast stove 1.

[0038] The calcined coal gangue and the heat-conducting spheres are continuously discharged from the discharge end 22. They are first separated by a screen, and the separated heat-conducting spheres are recycled back to the feed end 21, mixed with new coal gangue, and then added back to the material chamber 23. The separated coal gangue is then cooled to below 80°C by a cooling belt and continuously collected for later use.

[0039] The difference between the non-continuous feeding mode and the continuous feeding mode described above is as follows: After the coal gangue fills the material cavity 23, the feed end 21 and the discharge end 22 are closed. After the coal gangue in the high-temperature calcination section has completed all calcination, the corresponding amount of coal gangue is discharged from the discharge end 22 and the next batch of coal gangue is added for feeding and calcination.

[0040] During the gradual increase of temperature in the coal gangue in activation reactor 2, the hydroxyl structural water of kaolinite in the coal gangue is gradually removed, and the aluminum-oxygen octahedrons and silicon-oxygen tetrahedra depolymerize, transforming the ordered kaolinite structure into a disordered and easily reactive metakaolinite structure. The specific chemical formula is: Al₂O₃·2SiO₂·2H₂O (kaolinite) → Al₂O₃·2SiO₂ (metakaolinite) + 2H₂O When the coal gangue reaches the preset calcination temperature of 1050℃, metakaolinite decomposes into amorphous SiO2 and γ-Al2O3. The specific chemical formulas are: Al₂O₃·2SiO₂ (metakaolinite) → γ-Al₂O₃ + 2SiO₂ The thermochemical reaction during the calcination of coal gangue is actually a combined result of the dehydroxylation reaction of kaolinite and the combustion and release reaction of organic carbon. The dehydroxylation reaction is endothermic, and its occurrence is influenced to some extent by the combustion of coal gangue. In an oxygen-free or low-oxygen environment, volatiles and organic carbon do not burn, thus not generating excess heat. In this environment, the internal heating rate of the coal gangue particles is slow, and the overall temperature of the material layer rises slowly. Simultaneously, the low oxygen concentration prevents the violent combustion of volatiles and organic carbon, thus avoiding the over-burning of the outer layer and the formation of mullite.

[0041] Three samples, each weighing 1800g, were taken from the raw granular coal gangue and designated as Sample 1, Sample 2, and Sample 3, respectively. Three samples, each weighing 1800g, were also taken from the calcined coal gangue. The silica conversion rate of the above samples was measured.

[0042] Before and after calcination, the quartz in coal gangue remains unchanged, while the crystal structure of kaolinite (containing silicon dioxide) changes. The low activity of natural coal gangue is mainly due to its composition of silicon dioxide and alumina. Silicon dioxide is a tetrahedral crystal with regular silicon and oxygen atoms, making it a very low-activity acidic oxide. In the alumina lattice, oxygen ions are hexagonally close-packed, and aluminum ions are symmetrically distributed around octahedral coordination centers formed by oxygen ions, resulting in high lattice energy, high melting and boiling points, and low activity. Activation calcination disrupts this stable crystal structure of kaolinite, placing silicon dioxide and alumina in a metastable state, thus giving it activity.

[0043] For coal gangue samples before calcination, silica exists in the form of kaolin and is inactive; during alkali dissolution, silica is difficult to react with sodium hydroxide and cannot precipitate from the sample. For coal gangue samples after calcination, silica is in a free state and is active; during alkali dissolution, silica readily reacts with sodium hydroxide and precipitates from the sample.

[0044] The mass of silica in the samples was measured using the silicomolybdenum blue colorimetric method, and the mass of aluminum oxide was measured using the EDTA (ethylenediaminetetraacetic acid) complexometric titration method. For samples before calcination, the aforementioned methods were used directly to measure the mass of silica and aluminum oxide. For samples after calcination, the samples were first subjected to alkaline dissolution to remove silica, and then the aforementioned methods were used to measure the mass of silica and aluminum oxide. The alkaline dissolution process involved adding the calcined sample to a sodium hydroxide solution at a liquid-to-solid ratio of 8:1, at a temperature of 80°C, and for a reaction time of 3 hours. The sodium hydroxide solution had a mass concentration of 300 g / L.

[0045] The activation and calcination effect was evaluated using the aluminum-to-silicon ratio of the samples. The aluminum-to-silicon ratio of the sample was calculated by dividing the mass of aluminum oxide by the mass of silicon dioxide. The results are shown in Table 1.

[0046] Table 1

[0047] As shown in Table 1, the aluminum-silicon ratio of granular coal gangue before calcination using the method described in this application was 0.86-0.9. After calcination using the method described in this application, the aluminum-silicon ratio of granular coal gangue increased to 3.50-3.59. This indicates that after activation and calcination, kaolinite in the coal gangue generated amorphous or metastable silica, which was removed after alkali dissolution. This proves that the kaolinite in the coal gangue underwent a complete crystal transformation, generating highly active amorphous aluminum-silicon compounds, demonstrating a significant activation and calcination effect.

[0048] Therefore, the method of this application adopts moving bed calcination and partition wall heating to calcine coal gangue in an oxygen-free atmosphere and remove volatile gases during the calcination process. The calcination temperature can be controlled to achieve the crystal transformation of silicon-aluminum compounds in coal gangue, produce highly active amorphous substances, and avoid the appearance of low-activity high-temperature crystalline substances, thus achieving precise control of crystal form.

[0049] In the description of this application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0050] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0051] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a connection that allows communication between components; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0052] In this application, the terms "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0053] Although embodiments of this application have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting this application. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of this application.

Claims

1. A coal gangue activation and calcination device, characterized in that, include: A hot air furnace, the hot air furnace having a combustion chamber for combustion to generate high-temperature flue gas or to introduce hot air; An activation reactor extends from above the hot blast stove through the combustion chamber to below the hot blast stove. The upper end of the activation reactor is the feed end, and the lower end is the discharge end. A material chamber is formed in the activation reactor for loading coal gangue. The high-temperature flue gas or hot air in the combustion chamber is transferred to the coal gangue in the material chamber through the side wall of the activation reactor, so that the coal gangue can be calcined in the material chamber under low oxygen or oxygen-free conditions.

2. The coal gangue activation and calcination equipment according to claim 1, characterized in that, The sidewall of the activation reactor is provided with a plurality of air guide holes spaced apart, which are used to introduce the volatile gas in the material chamber into the combustion chamber.

3. The coal gangue activation and calcination equipment according to claim 2, characterized in that, An air guide portion extending into the combustion chamber is formed on the outer wall of the activation reactor at the air guide hole, and the air guide hole extends along the length direction of the air guide portion.

4. The coal gangue activation and calcination equipment according to claim 1, characterized in that, The discharge end of the activation reactor is equipped with a valve, and the valve can adjust the falling speed of coal gangue in the material chamber by adjusting the opening degree.

5. The coal gangue activation and calcination equipment according to any one of claims 1-4, characterized in that, It also includes heat-conducting spheres, which are mixed with coal gangue and placed in the activation reactor. The heat-conducting spheres are used to transfer heat from the inner wall of the activation reactor to the material chamber.

6. The coal gangue activation and calcination equipment according to claim 5, characterized in that, The thermally conductive sphere is made of alumina or silicon carbide. And / or, the diameter of the thermally conductive sphere is 1 to 20 mm.

7. The coal gangue activation and calcination equipment according to any one of claims 1-4, characterized in that, It also includes a screen, which is disposed below the discharge end of the activation reactor; And / or, it also includes a cooling belt disposed below the discharge end of the activation reactor.

8. The coal gangue activation and calcination equipment according to claim 1, characterized in that, One end of the hot air furnace is connected to the burner, and the other end has an air outlet. A thermocouple is installed inside the hot air furnace.

9. A method for activating and calcining coal gangue, characterized in that, The coal gangue activation and calcination equipment according to any one of claims 1-8, wherein the calcination method comprises: Coal gangue is added to the material chamber from the feed end of the self-activation reactor. The coal gangue in the material chamber is isolated from the high-temperature flue gas or hot air in the combustion chamber of the hot blast stove. The coal gangue is in an oxygen-free or low-oxygen environment in the activation reactor. The activation reactor is heated by the hot flue gas or hot air in the combustion chamber. The heat from the activation reactor is transferred to the material chamber. The coal gangue gradually heats up as it moves down in the material chamber until it reaches the preset calcination temperature. The coal gangue descends in the material chamber for a preset calcination time to complete the material decomposition and crystal transformation; The volatile gases generated during the calcination of coal gangue are introduced into the combustion chamber through the gas guide hole for combustion; The calcined coal gangue is discharged from the outlet of the activated reactor.

10. The method for activating and calcining coal gangue according to claim 9, characterized in that, The preset calcination time is 1-40 hours; And / or, the preset calcination temperature is 900-1150℃.

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