Coal gangue suspension roasting equipment and roasting process

Abstract

The invention relates to the field of coal gangue roasting, in particular to coal gangue suspension roasting equipment and a roasting technology.The roasting equipment comprises a preheating device, a roasting device, a hot air device, a cooling device and a heat recovery device, and a feeding port of the preheating device communicates with a coal gangue feeding channel and is used for preheating coal gangue; a feed port of the roasting device is communicated with a discharge port of the preheating device, an air outlet of the roasting device is communicated with a feed port of the preheating device, and the roasting device is used for roasting coal gangue; an air outlet of the hot air device is communicated with a feeding hole of the roasting device and is used for generating hot air; a feed port of the cooling device is communicated with a discharge port of the roasting device, an air outlet of the cooling device is communicated with the hot air device, a discharge port of the cooling device is communicated with the stock bin, and the cooling device is used for cooling roasted coal gangue; by means of the coal gangue waste heat utilization device, coal gangue can be burnt more stably, waste heat of waste gas is utilized, and the content of harmful gas in exhausted gas is reduced.

Description

Technical Field

[0001] The present application relates to the technical field of suspended roasting of coal gangue, and in particular to a suspended roasting device and a roasting process for coal gangue. Background Art

[0002] Gangue often contains a lot of combustible materials, and the combustion temperature range of combustible materials is wide. When using suspended preheating decomposition technology, the combustion in the calciner is unstable and the temperature distribution is uneven, which will lead to unstable quality of the calcined product. At the same time, the flame of the traditional suspended roasting furnace is in the main furnace of the roasting furnace. When the gangue is roasted, some materials will pass through the activation center, resulting in excessively high roasting temperatures for some gangue and loss of material activity. The cooling air of the traditional suspended roasting furnace enters the roasting furnace from the bottom of the main furnace of the roasting furnace. The cooling air carries a large amount of material, which will still pass through the center of the roasting furnace flame, resulting in excessively high roasting temperatures for some gangue and loss of material activity. Gangue contains a large amount of coal. The material residence time in traditional roasting furnaces is short, and the gangue decarbonization effect in the reaction tank is poor, making it difficult to meet the activation and decarbonization requirements of gangue roasting. In addition, coal gangue contains a certain amount of harmful organic volatile gases, which will produce carbon monoxide, nitrogen oxides and volatile organic compounds after roasting, leading to excessive emissions of waste gas pollutants. Summary of the Invention

[0003] The present application provides a coal gangue suspension roasting device and roasting process, which are used to solve the problems of unstable combustion in the calcining furnace and excessive emission of roasting waste gas pollutants in the prior art.

[0004] In one aspect, the present application provides a coal gangue suspension roasting device, comprising:

[0005] A preheating device, wherein the feed port of the preheating device is connected to the gangue feed channel and is used to preheat the gangue;

[0006] A roasting device is provided on the downstream side of the preheating device, wherein the feed port of the roasting device is connected to the discharge port of the preheating device, and the gas outlet of the roasting device is connected to the feed port of the preheating device, and is used to roast the preheated coal gangue;

[0007] A hot air device, the air outlet of the hot air device is connected to the feed inlet of the roasting device, and is used to generate hot air;

[0008] A cooling device is provided on the downstream side of the roasting device, wherein the feed port of the cooling device is connected to the discharge port of the roasting device, the air outlet of the cooling device is connected to the hot air device, and the discharge port of the cooling device is connected to the silo, for cooling the coal gangue after roasting;

[0009] A heat recovery device is provided, wherein an air inlet of the heat recovery device is communicated with an air outlet of the preheating device.

[0010] In one possible design, the preheating device includes a first-stage preheater, a second-stage preheater and a third-stage preheater. The discharge port of the first-stage preheater is connected to the feed port of the second-stage preheater, and the discharge port of the second-stage preheater is connected to the feed port of the third-stage preheater.

[0011] In one possible design, the roasting apparatus includes:

[0012] A roasting furnace, wherein the feed port of the roasting furnace is connected to the discharge port of the three-stage preheater;

[0013] The retention tank has a feed port connected to the discharge port of the roasting furnace, and a gas outlet of the retention tank is connected to the feed port of the roasting furnace.

[0014] In one possible design, the hot air device includes:

[0015] Blower, used to transport fuel, combustible gas and combustion-supporting gas;

[0016] A combustion chamber, wherein the air inlet of the combustion chamber is connected to the fan, and the air outlet of the combustion chamber is connected to the air inlet of the retention tank;

[0017] The mixing chamber is communicated with the gas outlet of the combustion chamber, and the gas outlet of the mixing chamber is communicated with the feed port of the roasting furnace.

[0018] In one possible design, the cooling device includes:

[0019] A primary cooler, wherein the feed port of the primary cooler is connected to the discharge port of the retention tank;

[0020] A secondary cooler, wherein the feed port of the secondary cooler is connected to the discharge port of the primary cooler, and the air outlet of the secondary cooler is connected to the feed port of the primary cooler;

[0021] A three-stage cooler, wherein the feed port of the three-stage cooler is connected to the discharge port of the two-stage cooler, and the air outlet of the three-stage cooler is connected to the feed port of the two-stage cooler;

[0022] A fourth-stage cooler, wherein the feed port of the fourth-stage cooler is connected to the discharge port of the third-stage cooler, and the air outlet of the fourth-stage cooler is connected to the feed port of the third-stage cooler;

[0023] A cooling bed, wherein the feed port of the cooling bed is connected to the discharge port of the four-stage cooler, and the discharge port of the cooling bed is connected to the silo;

[0024] The centrifugal separator has a feed port connected to the air outlet of the primary cooler, a discharge port of the centrifugal separator is connected to the feed port of the primary cooler, and a air outlet of the centrifugal separator is connected to the mixing chamber.

[0025] In one possible design, the heat recovery device includes:

[0026] A first-stage heat recovery device, wherein the air inlet of the first-stage heat recovery device is connected to the air outlet of the first-stage preheater;

[0027] The air inlet of the secondary heat recovery device is connected to the air outlet of the primary heat recovery device.

[0028] In one possible design, the primary heat recovery unit and the secondary heat recovery unit each include:

[0029] The first reaction tank is provided with an air inlet;

[0030] The second reaction tank is provided with a heat recovery gas inlet and a purified gas outlet;

[0031] An intermediate pipeline, both ends of which are connected to the interiors of the first reaction tank and the second reaction tank respectively;

[0032] The oxygen carrier can flow in the middle pipeline to realize the circulation flow in the first reaction tank and the second reaction tank;

[0033] The first heat exchange tube is sleeved on the outer circumference of the first reaction tank and is filled with heat exchange medium.

[0034] In one possible design, the equipment also includes a powder separator, which is arranged between the first-level preheater and the first-level heat recovery device, the feed port of the powder separator is connected to the air outlet of the first-level preheater, the discharge port of the powder separator is connected to the feed port of the first-level preheater, and the air outlet of the powder separator is connected to the air inlet of the first-level heat recovery device.

[0035] In one possible design, the equipment further includes a dust collector, which is disposed between the primary heat recovery device and the secondary heat recovery device, and the discharge port of the dust collector is connected to the feed port of the primary preheater.

[0036] On the other hand, the present application also provides a gangue suspension roasting process, including the gangue suspension roasting equipment as described above, and the roasting process includes:

[0037] The ground coal gangue enters the preheating device for preheating;

[0038] The preheated gangue enters the roasting device for roasting and crystal transformation;

[0039] The coal gangue after crystallization enters the cooling device for cooling and is collected into the silo after cooling;

[0040] The hot air during the roasting process enters the heat recovery device for purification and heat recovery.

[0041] The beneficial effects of this application are as follows:

[0042] The gangue suspension roasting equipment of the present application, by providing a multi-stage preheating device, roasting device, and multi-stage cooling device, can achieve more stable gangue combustion and improve the quality of the calcined product. It can prevent the material from directly contacting the flame, meet the material's high-temperature crystallization time requirements, and achieve the gangue decarbonization requirements. The heat recovery device can fully utilize the waste heat of the exhaust gas and greatly reduce the production of carbon monoxide, nitrogen oxides, and volatile organic compounds, which helps reduce pollution to the atmospheric environment.

[0043] The gangue suspension roasting process provided in the present application adopts the gangue suspension roasting equipment in the present application, and therefore includes all the above-mentioned advantages of the gangue suspension roasting equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] In order to more clearly illustrate the specific implementation methods of the present application or the technical solutions in the prior art, the following is a brief introduction to the drawings required for use in the specific implementation methods or the description of the prior art. Obviously, the drawings described below are some implementation methods of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0045] Figure 1 Schematic diagram of the equipment flow of the gangue suspension roasting equipment provided in the embodiment of the present application;

[0046] Figure 2 This is a schematic structural diagram of the primary heat recovery device and the secondary heat recovery device of the gangue suspension roasting equipment provided in the embodiment of the present application.

[0047] Reference numerals:

[0048] 110. Primary preheater; 120. Secondary preheater; 130. Tertiary preheater; 210. Roasting furnace; 220. Stay tank; 230. Blower; 240. Combustion chamber; 250. Mixing chamber; 310. Primary cooler; 320. Secondary cooler; 330. Tertiary cooler; 340. Fourth-stage cooler; 350. Cooling bed; 360. Centrifugal separator; 410. Primary heat recovery device; 420. Secondary heat recovery device; 411. First reaction tank; 412. Second reaction tank; 413. Intermediate pipeline; 414. Oxygen carrier; 415. First heat exchange tube; 416. Air inlet; 417. Heat recovery gas inlet; 418. Purified gas outlet; 500. Powder separator; 600. Dust collector; 700. Induced draft fan. DETAILED DESCRIPTION

[0049] The following will clearly and completely describe the technical solutions of this application in conjunction with the embodiments. Obviously, the embodiments described are only part of the embodiments of this application, not all of them. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0050] The following combination Figure 1-Figure 2 , describing the gangue suspension roasting equipment and roasting process provided in the embodiments of the present application.

[0051] Reference Figure 1 As shown, the coal gangue suspension roasting equipment provided in the embodiment of the present application includes a preheating device, a roasting device, a hot air device, a cooling device, and a heat recovery device. The feed port of the preheating device is connected to the feed channel of the ground coal gangue. The ground coal gangue first enters the preheating device for preheating, then enters the roasting device for roasting and crystallization. The crystallized coal gangue enters the cooling device for cooling. After cooling, it is collected in a silo. The hot air during the roasting process enters the heat recovery device for purification and heat recovery.

[0052] Reference Figure 1 As shown, in some specific embodiments, the preheating device includes a primary preheater 110, a secondary preheater 120, and a tertiary preheater 130. The discharge port of the primary preheater 110 is connected to the feed port of the secondary preheater 120, and the discharge port of the secondary preheater 120 is connected to the feed port of the tertiary preheater 130. The primary preheater 110, the secondary preheater 120, and the tertiary preheater 130 are each a cyclone preheater.

[0053] The roasting device is arranged on the downstream side of the preheating device, and the feed port of the roasting device is connected to the discharge port of the preheating device, and the gas outlet of the roasting device is connected to the feed port of the preheating device. In some specific embodiments, the roasting device includes a roasting furnace 210 and a retention tank 220, the feed port of the roasting furnace 210 is connected to the discharge port of the three-stage preheater 130, and the preheated coal gangue is roasted in the roasting furnace 210; the feed port of the retention tank 220 is connected to the discharge port of the roasting furnace 210, and the gas outlet of the retention tank 220 is connected to the feed port of the roasting furnace 210, and the roasted coal gangue is transformed into crystals in the retention tank 220.

[0054] The heat source of the roasting device is a hot air device, and the air outlet of the hot air device is connected to the feed inlet of the roasting device to generate hot air. In some specific embodiments, the hot air device includes a blower, a combustion chamber 240 and a mixing chamber 250. The air inlet of the combustion chamber 240 is connected to the blower 230. The blower 230 is used to transport fuel, combustible gas and combustion-supporting gas. For example, natural gas, air or oxygen, combustion-supporting air, etc. are respectively transported to the combustion chamber 240 through multiple Roots blowers. The air outlet of the combustion chamber 240 is connected to the air inlet of the retention tank 220, which is used to increase the high-temperature gas to the retention tank 220 so as to fluidize the roasted coal gangue and perform crystallization in the retention tank 220. The mixing chamber 250 is connected to the air outlet of the combustion chamber 240, and the air outlet of the mixing chamber 250 is connected to the feed inlet of the roasting furnace 210, so as to provide high-temperature fluidizing gas to the roasting furnace 210.

[0055] The cooling device is arranged on the downstream side of the roasting device, the feed port of the cooling device is connected to the discharge port of the roasting device, the air outlet of the cooling device is connected to the hot air device, and the discharge port of the cooling device is connected to the hopper, so as to cool the coal gangue after roasting. Specifically, the cooling device includes a primary cooler 310, a secondary cooler 320, a tertiary cooler 330, a fourth cooler 340, a cooling bed 350 and a centrifugal separator 360, the feed port of the primary cooler 310 is connected to the discharge port of the retention tank 220, the feed port of the secondary cooler 320 is connected to the discharge port of the primary cooler 310, the air outlet of the secondary cooler 320 is connected to the feed port of the primary cooler 310, the feed port of the tertiary cooler 330 is connected to the discharge port of the secondary cooler 320, and the air outlet of the tertiary cooler 330 is connected to the secondary cooler The feed port of the fourth-stage cooler 340 is connected to the discharge port of the third-stage cooler 330, the air outlet of the fourth-stage cooler 340 is connected to the feed port of the third-stage cooler 330, the feed port of the cooling bed 350 is connected to the discharge port of the fourth-stage cooler 340, and the discharge port of the cooling bed 350 is connected to the silo; the feed port of the centrifugal separator 360 is connected to the air outlet of the first-stage cooler 310, the discharge port of the centrifugal separator 360 is connected to the feed port of the first-stage cooler 310, and the air outlet of the centrifugal separator 360 is connected to the mixing chamber 250.

[0056] The air inlet of the heat recovery device is connected to the air outlet of the preheating device. Specifically, the heat recovery device includes a primary heat recovery unit 410 and a secondary heat recovery unit 420. The air inlet of the primary heat recovery unit 410 is connected to the air outlet of the primary preheater 110, and the air inlet of the secondary heat recovery unit 420 is connected to the air outlet of the primary heat recovery unit 410. In some embodiments, the primary heat recovery unit 410 and the secondary heat recovery unit 420 can be boilers or other heat exchangers.

[0057] Reference Figure 2As shown, in some specific embodiments, the primary heat recovery unit 410 and the secondary heat recovery unit 420 are heat recovery structures that utilize a chemical reaction chain to achieve heat recovery. Specifically, they include a first reaction tank 411, a second reaction tank 412, an intermediate pipeline 413, an oxygen carrier 414, and a first heat exchange tube 415. The oxygen carrier 414 is filled in the first and second reaction tanks 411, 412. For example, the oxygen carrier 414 is iron oxide powder or nickel oxide powder, and is driven by airflow to flow between the first and second reaction tanks 411, 412. Specifically, an air inlet 416 is provided on the first reaction tank 411, and a heat recovery gas inlet 417 and a purified gas outlet 418 are provided on the second reaction tank 412; the two ends of the intermediate pipeline 413 are respectively connected to the interior of the first reaction tank 411 and the second reaction tank 412; the oxygen carrier 414 can flow in the intermediate pipeline 413 to realize a circulation flow in the first reaction tank 411 and the second reaction tank 412; the first heat exchange tube 415 is sleeved on the outer periphery of the first reaction tank 411, and the first heat exchange tube 415 is filled with a heat exchange medium, for example, the heat exchange medium is desalted water.

[0058] During the heat recovery process, the intermediate pipeline 413 always remains open and unobstructed. Since the oxygen carrier 414 always flows to a space with low air pressure, when the air inlet 416 is opened and the heat recovery gas inlet 417 and the purge gas outlet 418 are closed, the air pressure in the first reaction tank 411 is higher than that in the second reaction tank 412, prompting the oxygen carrier 414 to flow to the second reaction tank 412; when the air inlet 416 and the purge gas outlet 418 are closed and the heat recovery gas inlet 417 is opened, the air pressure in the first reaction tank 411 is higher than that in the second reaction tank 412, prompting the oxygen carrier 414 to flow to the first reaction tank 411. When the purge gas outlet 418 is opened and the heat recovery gas inlet 417 is closed, the purge gas is discharged from the purge gas outlet 418. A filter element is installed at the purge gas outlet 418 to prevent the oxygen carrier from being discharged. In this way, the reduced oxygen carrier 414 undergoes a fluidized oxidation reaction with the air in the first reaction tank 411 to form an oxidized oxygen carrier 414. The reduced oxygen carrier 414 undergoes a fluidized oxidation reaction with the air, and the oxidation reaction releases a large amount of heat energy. The heat energy is absorbed by the first heat exchange tube 415 and transmitted to other coal gangue production equipment for use, thereby realizing the recovery and utilization of heat energy; the air pressure in the first reaction tank 411 gradually increases, prompting the oxidized oxygen carrier 414 to enter the second reaction tank 412 through the intermediate pipeline 413, and the oxidized oxygen carrier 414 undergoes a reduction combustion reaction with the heat recovery gas in the second reaction tank 412 to form the reduced oxygen carrier 414. The oxidized oxygen carrier 414 and the heat recovery gas remove hydrocarbons, carbon monoxide, nitrogen oxides, and sulfides in the exhaust gas through the combustion reaction, and generate harmless carbon dioxide, water, sulfates, metal oxides, etc., thereby realizing the purification and removal of harmful gases in the exhaust gas. The gas pressure in second reaction tank 412 gradually increases. Under the influence of the gas pressure, oxidized oxygen carrier 414 flows back to first reaction tank 411 through intermediate pipeline 413. By alternating the opening of air inlet 416 and heat recovery gas inlet 417, oxygen carrier 414 is circulated, thereby purifying the exhaust gas and recovering the exhaust gas heat. Furthermore, this application utilizes chemical looping combustion, transferring oxygen atoms through oxygen carrier 414. The reaction temperature is relatively low, and the combustion process is controllable, significantly suppressing the formation of thermal nitrogen oxides and reducing pollution to the atmospheric environment.

[0059] In some embodiments, the equipment also includes a powder separator 500, which is a centrifugal separator 360, arranged between the first-level preheater 110 and the first-level heat recovery device 410, the feed port of the powder separator 500 is connected to the air outlet of the first-level preheater 110, the discharge port of the powder separator 500 is connected to the feed port of the first-level preheater 110, and the air outlet of the powder separator 500 is connected to the air inlet of the first-level heat recovery device 410, for separating the gas from the powder.

[0060] In some embodiments, the apparatus further includes a dust collector 600 disposed between the primary heat recovery unit 410 and the secondary heat recovery unit 420. The discharge port of the dust collector 600 is connected to the feed port of the primary preheater 110 to separate the gas from the powder. An induced draft fan 700 is also included, disposed at the rear end of the powder separator 500 and between the primary heat recovery unit 410 and the secondary heat recovery unit 420.

[0061] On the other hand, the present application also provides a coal gangue suspension roasting process, including the coal gangue suspension roasting equipment in the above embodiment, and the roasting process includes: the ground coal gangue enters the preheating device for preheating; the preheated coal gangue enters the roasting device for roasting and crystallization; the coal gangue after crystallization enters the cooling device for cooling, and is collected into the silo after cooling; the hot air during the roasting process enters the heat recovery device for purification and heat recovery.

[0062] The specific steps include:

[0063] Step 1: Start the induced draft fan 700 to maintain a slight negative pressure in the roasting furnace 210 system, and allow air to enter the cooling bed 350, the fourth-stage cooler 340, the third-stage cooler 330, the second-stage cooler 320, the first-stage cooler 310, the centrifugal separator 360, the retention tank 220, the roasting furnace 210, the third-stage preheater 130, the second-stage preheater 120, the first-stage preheater 110, the powder separator 500, the first-stage heat recovery device 410, the dust collector 600, the second-stage heat recovery device 420 and the chimney in sequence, and then be discharged into the atmosphere;

[0064] Step 2: Adjust the frequency of the induced draft fan 700 to gradually increase the exhaust volume and exhaust pressure, so that the negative pressure of the roasting furnace 210 is adjusted to a pressure suitable for ignition, start the burner to start ignition, and when the temperature of the first-stage preheater 110 of the roasting furnace 210 is greater than 480°C, add the ground coal gangue powder;

[0065] Step 3: The raw materials in the gangue powder silo are fed into the primary cyclone preheater through a weighing scale and a feeder. The flue gas and the material enter the primary preheater 110 together for heat exchange and gas-solid separation. The separated dust-laden flue gas enters the powder separator 500 for cyclone separation. The separated powder material enters the primary preheater 110 again. The flue gas from the powder separator 500 enters the primary heat recovery device 410 through the induced draft fan 700 for primary heat recovery and purification, and is then sent to the secondary heat recovery device 420 through the induced draft fan 700 for secondary heat recovery and purification, and is finally discharged into the atmosphere through the chimney. The ash return device sends the collected dust from the waste heat boiler and the dust collector 600 into the primary preheater 110 and enters the roasting system again.

[0066] Step 4: The raw materials in the gangue powder silo are preheated in the primary preheater 110, and the gas-solid separated materials are sequentially fed into the secondary preheater 120, the tertiary preheater 130, the roasting furnace 210, and the retention tank 220, where the materials undergo crystal transformation and decarbonization. The system temperature of the roasting furnace 210 is gradually increased to the required temperature of 950-1100°C. After the gangue powder gradually reaches the expected index, it passes through the discharge port of the retention tank 220 and sequentially passes through the primary cooler 310, the centrifugal separator 360, the secondary cooler 320, the tertiary cooler 330, and the quaternary cooler 340. After the material is cooled to below 300°C, it enters the cooling bed 350 and is finally cooled to below 150°C.

[0067] Step 5: When the temperature in the roasting furnace 210 reaches a predetermined temperature, for example, 950-1100°C, the temperature of the material in the retention tank 220 gradually increases, but the temperature is still lower than the temperature of the roasting furnace 210 and lower than the crystallization temperature required for the coal gangue powder. Start the blower 230 and adjust the fan frequency and wind pressure. Blow the fluidized air heated by the burner into the retention tank 220 to provide high-temperature air for the retention tank 220 and increase the temperature of the retention tank 220 to the temperature required for crystallization. The material stays in the retention tank 220 for 5-30 minutes.

[0068] Step 6: When the feed load is greater than 80%, the high-temperature flue gas coming out of the powder separator 500 enters the primary heat recovery device 410 and the secondary heat recovery device 420 for waste heat recovery and desulfurization and denitrification.

[0069] Step 7: Adjust the flow rate of the primary heat recovery device 410 and the secondary heat recovery device 420 to ensure that the exhaust gas temperature of the induced draft fan 700 is 160-180°C.

[0070] Step 8: The cooling air of the cooling bed 350 is sent into the cooling bed 350 by the fan. The fan frequency is adjusted to adjust the air volume and air pressure. The air after passing through the cooling bed 350 enters the four-stage cooler 340. The insufficient air volume of the system can be supplemented into the roasting furnace 210 through the inlet pipe of the four-stage cooler 340.

[0071] In the description of the present application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0072] 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 the technical features being referred to. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of such features. Throughout the description of this application, "plurality" means at least two, for example, two, three, etc., unless otherwise specifically defined.

[0073] In this application, unless otherwise specified or limited, the terms "installed," "connected," "connect," "fixed," etc. should be understood in a broad sense. For example, they can refer to fixed connection, detachable connection, or integration; mechanical connection, electrical connection, or communication; direct connection or indirect connection through an intermediate medium; internal communication between two elements or interaction between two elements, unless otherwise specified. Those skilled in the art will understand the specific meanings of the above terms in this application based on specific circumstances.

[0074] In this application, the terms "one embodiment", "some embodiments", "examples", "specific examples", or "some examples" mean that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art can combine and combine different embodiments or examples described in this specification and the features of different embodiments or examples without contradiction.

[0075] Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limitations on the present application. Ordinary technicians in this field can change, modify, replace and modify the above embodiments within the scope of the present application.

Claims

1. A coal gangue suspension roasting equipment, characterized in that: include: A preheating device, wherein the feed port of the preheating device is connected to the gangue feed channel and is used to preheat the gangue; a roasting device, disposed on the downstream side of the preheating device, wherein the feed port of the roasting device is connected to the discharge port of the preheating device, and the gas outlet of the roasting device is connected to the feed port of the preheating device, and is used to roast the preheated coal gangue; a hot air device, the air outlet of which is connected to the feed inlet of the roasting device, for generating hot air; A cooling device is provided on the downstream side of the roasting device, wherein the feed port of the cooling device is connected to the discharge port of the roasting device, the air outlet of the cooling device is connected to the hot air device, and the discharge port of the cooling device is connected to the silo, for cooling the coal gangue after roasting; A heat recovery device, wherein the air inlet of the heat recovery device is connected to the air outlet of the preheating device.

2. The gangue suspension roasting equipment according to claim 1, characterized in that: The preheating device includes a primary preheater, a secondary preheater and a tertiary preheater. The discharge port of the primary preheater is connected to the feed port of the secondary preheater, and the discharge port of the secondary preheater is connected to the feed port of the tertiary preheater.

3. The gangue suspension roasting equipment according to claim 2, characterized in that: The roasting device comprises: a roasting furnace, wherein the feed port of the roasting furnace is connected to the discharge port of the three-stage preheater; A retention tank, wherein the feed port of the retention tank is connected to the discharge port of the roasting furnace, and the gas outlet of the retention tank is connected to the feed port of the roasting furnace.

4. The gangue suspension roasting equipment according to claim 3, characterized in that: The hot air device comprises: Blower, used to transport fuel, combustible gas and combustion-supporting gas; a combustion chamber, wherein the air inlet of the combustion chamber is connected to the fan, and the air outlet of the combustion chamber is connected to the air inlet of the retention tank; The mixing chamber is communicated with the gas outlet of the combustion chamber, and the gas outlet of the mixing chamber is communicated with the feed port of the roasting furnace.

5. The gangue suspension roasting equipment according to claim 4, characterized in that: The cooling device comprises: A primary cooler, wherein the feed port of the primary cooler is connected to the discharge port of the retention tank; A secondary cooler, wherein the feed port of the secondary cooler is connected to the discharge port of the primary cooler, and the air outlet of the secondary cooler is connected to the feed port of the primary cooler; A three-stage cooler, wherein the feed port of the three-stage cooler is connected to the discharge port of the two-stage cooler, and the air outlet of the three-stage cooler is connected to the feed port of the two-stage cooler; A fourth-stage cooler, wherein the feed port of the fourth-stage cooler is connected to the discharge port of the third-stage cooler, and the air outlet of the fourth-stage cooler is connected to the feed port of the third-stage cooler; A cooling bed, wherein the feed port of the cooling bed is connected to the discharge port of the four-stage cooler, and the discharge port of the cooling bed is connected to the silo; A centrifugal separator, wherein the feed port of the centrifugal separator is connected to the air outlet of the primary cooler, the discharge port of the centrifugal separator is connected to the feed port of the primary cooler, and the air outlet of the centrifugal separator is connected to the mixing chamber.

6. The gangue suspension roasting equipment according to claim 5, characterized in that: The heat recovery device comprises: a primary heat recovery device, wherein the air inlet of the primary heat recovery device is connected to the air outlet of the primary preheater; A secondary heat recovery device, wherein the air inlet of the secondary heat recovery device is connected to the air outlet of the primary heat recovery device.

7. The gangue suspension roasting equipment according to claim 6, characterized in that: The primary heat recovery device and the secondary heat recovery device respectively include: The first reaction tank is provided with an air inlet; The second reaction tank is provided with a heat recovery gas inlet and a purified gas outlet; an intermediate pipeline, wherein both ends of the intermediate pipeline are respectively connected to the interior of the first reaction tank and the second reaction tank; The oxygen carrier can flow in the intermediate pipeline to realize a circulation flow in the first reaction tank and the second reaction tank; The first heat exchange tube is sleeved on the outer circumference of the first reaction tank and is filled with heat exchange medium.

8. The gangue suspension roasting equipment according to claim 6 or 7, characterized in that: It also includes a powder separator, which is arranged between the first-level preheater and the first-level heat recovery device. The feed port of the powder separator is connected to the air outlet of the first-level preheater, the discharge port of the powder separator is connected to the feed port of the first-level preheater, and the air outlet of the powder separator is connected to the air inlet of the first-level heat recovery device.

9. The gangue suspension roasting equipment according to claim 6 or 7, characterized in that: It also includes a dust collector, which is arranged between the first-level heat recovery device and the second-level heat recovery device, and the discharge port of the dust collector is connected to the feed port of the first-level preheater.

10. A coal gangue suspension roasting process, characterized in that: The gangue suspension roasting equipment according to any one of claims 1 to 9 is used, and the roasting process includes: The ground coal gangue enters the preheating device for preheating; The preheated gangue enters the roasting device for roasting and crystal transformation; The coal gangue after crystallization enters the cooling device for cooling and is collected into the silo after cooling; The hot air during the roasting process enters the heat recovery device for purification and heat recovery.

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