Coal gangue mixed firing method

Abstract

The application provides a coal gangue mixed firing method, which comprises the following steps: pretreating coal gangue materials to screen coal gangue raw materials with different particle sizes, collecting coal gangue raw materials with particle sizes in a first preset range as gravel raw materials; collecting coal gangue raw materials with particle sizes in a second preset range and a heat value reaching a first preset heat value as water-retaining ceramic aggregate raw materials, and making the water-retaining ceramic aggregate raw materials into water-retaining ceramic aggregate semi-products; mixing and firing the gravel raw materials and the water-retaining ceramic aggregate semi-products, and screening after the mixing and firing to obtain gravel products and water-retaining ceramic aggregate products; and the value of the first preset range is greater than the value of the second preset range, so as to solve the problem of waste caused by directly discarding part of the coal gangue which is not suitable for making gravel after screening in the prior art.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of comprehensive utilization of coal gangue, in particular to a coal gangue mixed firing method. BACKGROUND

[0002] At present, a kind of black gray rock with low carbon content and hard quality than coal, which is a solid waste, is associated with coal mining and washing process, which is coal gangue. The most common disposal method at present is landfill, which not only occupies a large piece of land, but also pollutes the environment. There are many ways to comprehensively utilize coal gangue, and the application in the building material field is more common, such as brick firing, ecological soil making, and light ceramic particle production. Gravel is an important component of concrete and mortar, and gravel fired by coal gangue has the characteristics of high strength (about 10 Mpa) and low water absorption (less than 10%), which mainly replaces the gravel in concrete.

[0003] However, less than 50% of all coal gangue is suitable for firing coal gangue gravel. Secondly, the gravel raw material has no calorific value, and its firing is a crystal phase consolidation process, which consumes 300 kcal of heat energy per ton of raw material. If only gravel is produced, only natural gas can provide heat. The remaining coal gangue rich in calorific value after screening gravel raw materials is wasted, which is not economical. SUMMARY

[0004] The main purpose of the present application is to provide a coal gangue mixed firing method to solve the problem of waste caused by directly discarding part of the coal gangue that is not suitable for making gravel after screening in the prior art.

[0005] In order to achieve the above purpose, the present application provides a coal gangue mixed firing method, which comprises pretreating coal gangue materials to screen coal gangue raw materials with different particle sizes, collecting coal gangue raw materials with particle size values meeting a first preset range as gravel raw materials; collecting coal gangue raw materials with particle size values meeting a second preset range and calorific value reaching a first preset calorific value as water-retaining ceramic raw materials, and making them into water-retaining ceramic semi-products with particle size values meeting a third preset range; mixing and firing the gravel raw materials and the water-retaining ceramic semi-products, and screening after the mixed firing to obtain gravel products and water-retaining ceramic products; wherein the value of the first preset range is greater than the value of the second preset range.

[0006] Further, the method for screening the coal gangue material comprises: placing the coal gangue material into a first vibrating screen for first screening to obtain coal gangue raw materials with particle sizes in a first preset range, a fourth preset range and a fifth preset range; collecting the coal gangue raw materials with particle sizes in the fourth preset range and placing them into a first crusher to crush them to coal gangue raw materials with particle sizes in the first preset range and the fifth preset range; and placing the coal gangue raw materials with particle sizes in the first preset range and the fifth preset range after being crushed by the first crusher into a second vibrating screen for second screening to obtain coal gangue raw materials with particle sizes in the first preset range and the fifth preset range.

[0007] Further, the method for screening the coal gangue material further comprises: placing the coal gangue raw materials with particle sizes in the first preset range obtained after two times of screening into a dry separator for sorting to obtain coal gangue raw materials suitable for making gravels as gravel raw materials; collecting the coal gangue raw materials with particle sizes in the first preset range unsuitable for making gravels and the coal gangue raw materials with particle sizes in the fifth preset range after two times of screening, and placing the collected coal gangue raw materials into a second crusher for crushing to obtain coal gangue raw materials with particle sizes in a second preset range by the second crusher as water-retaining ceramic aggregate raw materials.

[0008] Further, the method for making the water-retaining ceramic aggregate raw materials into the water-retaining ceramic aggregate semi-finished products comprises: placing the water-retaining ceramic aggregate raw materials in a buffer bin, continuously feeding the vertical mill by the feeder, grinding the water-retaining ceramic aggregate raw materials with particle sizes in the second preset range into water-retaining ceramic aggregate raw materials with fineness in a sixth preset range by the vertical mill, and making the water-retaining ceramic aggregate raw materials with fineness in the sixth preset range into water-retaining ceramic aggregate semi-finished products.

[0009] Further, the method for making the water-retaining ceramic aggregate raw materials into the water-retaining ceramic aggregate semi-finished products further comprises: conveying the water-retaining ceramic aggregate raw materials with fineness in the sixth preset range into a mixer, adding pore-forming agents into the mixer, mixing the water-retaining ceramic aggregate raw materials with fineness in the sixth preset range and the pore-forming agents in a preset proportion, and conveying the mixed raw materials into a balling machine to make them into water-retaining ceramic aggregate semi-finished products by the balling machine.

[0010] Further, the coal gangue mixed firing method further comprises: mixing the water-retaining ceramic bead semi-finished product and the gravel raw material, and dividing them into two parts to be placed on a first material layer with a first preset thickness and a second material layer with a second preset thickness respectively; arranging a bedding material on a third material layer with a third preset thickness, and stacking the first material layer, the second material layer and the third material layer in order from top to bottom to obtain the to-be-fired raw material, and conveying the to-be-fired raw material into the sintering machine for firing to obtain the gravel finished product and the water-retaining ceramic bead finished product.

[0011] Further, the method of conveying the to-be-fired raw material into the sintering machine for firing comprises: conveying the to-be-fired raw material into the ignition drying area of the sintering machine to complete the process of igniting and drying the water-retaining ceramic bead semi-finished product and the gravel raw material; conveying the to-be-fired raw material after drying into the preheating decarburization area of the sintering machine to calcine the water-retaining ceramic bead semi-finished product and the gravel raw material; conveying the to-be-fired raw material after calcination into the cooling area of the sintering machine to cool it to obtain the gravel finished product and the water-retaining ceramic bead finished product; wherein the temperature of the ignition drying area is a first preset temperature, the temperature of the preheating decarburization area is a second preset temperature, and the temperature of the cooling area is a third preset temperature; the first preset temperature is less than the second preset temperature and greater than the third preset temperature.

[0012] Further, the coal gangue mixed firing method further comprises: discharging the heat in the preheating decarburization area to maintain the temperature of the preheating decarburization area at the second preset temperature.

[0013] Further, the coal gangue mixed firing method further comprises: discharging the high-temperature gas in the sintering machine to utilize the discharged high-temperature gas for waste heat power generation treatment.

[0014] Further, the first preset range is 30mm to 100mm; and the second preset range is less than 8mm.

[0015] Further, the fourth preset range is greater than 100mm; and the fifth preset range is less than 30mm.

[0016] Further, the sixth preset range is 50 mesh to 100 mesh.

[0017] Further, the first preset value is 400mm; the second preset value is 450mm; and the third preset value is 50mm.

[0018] Further, the first preset temperature is 180℃; the second preset temperature is 900℃; and the third preset temperature is 300℃.

[0019] Further, the first preset heat value is 300 large calories to 3000 large calories; and the third preset range is 10mm to 16mm.

[0020] The coal gangue mixed firing method comprises the following steps: pretreating coal gangue materials to screen coal gangue raw materials with different particle sizes, collecting coal gangue raw materials with a particle size value in a first preset range as gravel raw materials; collecting coal gangue raw materials with a particle size value in a second preset range and a heat value reaching a first preset heat value as water-retaining ceramic aggregate raw materials, and processing the water-retaining ceramic aggregate raw materials into water-retaining ceramic aggregate semi-products with a particle size value in a third preset range; mixing and firing the gravel raw materials and the water-retaining ceramic aggregate semi-products, and screening after the mixing and firing to obtain gravel products and water-retaining ceramic aggregate products; and the value of the first preset range is greater than the value of the second preset range. The method screens coal gangue materials with different particle size values to obtain coal gangue raw materials with a particle size value in a first preset range as gravel raw materials; meanwhile, coal gangue raw materials with a particle size value not in the first preset range are collected to prevent waste and are crushed and screened to further obtain coal gangue raw materials with a particle size value in the first preset range and not in the first preset range, coal gangue raw materials not in the first preset range and with a first preset heat value are collected and are crushed to obtain coal gangue raw materials with a particle size value in a second preset range as water-retaining ceramic aggregate raw materials and are processed into water-retaining ceramic aggregate semi-products with a particle size value in a third preset range; the gravel raw materials and the prepared water-retaining ceramic aggregate semi-products are mixed and fired to obtain gravel products and water-retaining ceramic aggregate products, thereby solving the problem of waste caused by directly discarding part of the coal gangue not suitable for making gravel after screening in the prior art. BRIEF DESCRIPTION OF DRAWINGS

[0021] The accompanying drawings, which form a part of the specification, are included to provide a further understanding of the application and are incorporated herein by reference. The embodiments disclosed in the drawings are illustrative of the present application and are not meant to limit the present application. In the drawings:

[0022] Figure 1 FIG. 1 shows a structure schematic diagram of an embodiment of a coal gangue mixed firing equipment corresponding to the coal gangue mixed firing method according to the present application;

[0023] Figure 2 FIG. 2 shows a structure schematic diagram of a coal gangue mixed firing equipment corresponding to the coal gangue mixed firing method according to the present application; Figure 1 FIG. 3 shows a structure schematic diagram of a coal gangue mixed firing equipment corresponding to the coal gangue mixed firing method according to the present application.

[0024] In the above drawings, the following reference signs are used:

[0025] 10, first vibrating screen; 20, first crusher; 30, second vibrating screen; 40, dry separator; 50, second crusher; 60, buffer bin; 61, feeder; 62, vertical mill; 63, mixer; 64, balling machine; 70, sintering machine; 71, ignition and drying zone; 72, preheating and decarburization zone; 73, cooling zone. DETAILED DESCRIPTION

[0026] It should be noted that the embodiments in the present application and the features in the embodiments can be combined with each other without conflict. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0027] As shown in Figure 1 and Figure 2 The technical scheme of the present application provides a coal gangue mixed firing method, which comprises the following steps: pretreating coal gangue materials to screen coal gangue raw materials with different particle sizes, collecting coal gangue raw materials with a particle size value within a first preset range as gravel raw materials; collecting coal gangue raw materials with a particle size value within a second preset range and a heat value reaching a first preset heat value as water-retaining ceramsite raw materials, and processing the water-retaining ceramsite raw materials into water-retaining ceramsite semi-products with a particle size value within a third preset range; mixing and firing the gravel raw materials and the water-retaining ceramsite semi-products, and screening after the mixing and firing to obtain gravel products and water-retaining ceramsite products; and the value of the first preset range is greater than the value of the second preset range.

[0028] The above method screens coal gangue materials with different particle size values to obtain coal gangue raw materials with a particle size value within a first preset range as gravel raw materials; at the same time, coal gangue raw materials with a particle size value not within the first preset range are collected to prevent waste and are crushed and screened to further obtain coal gangue raw materials with a particle size value within the first preset range and not within the first preset range, coal gangue raw materials not within the first preset range and with a first preset heat value are collected and are crushed to obtain coal gangue raw materials with a particle size value within a second preset range as water-retaining ceramsite raw materials to process water-retaining ceramsite semi-products with a particle size value within a third preset range; the gravel raw materials and the prepared water-retaining ceramsite semi-products are mixed and fired to obtain gravel products and water-retaining ceramsite products, thereby solving the problem of waste caused by directly discarding part of the coal gangue not suitable for making gravel after screening in the prior art.

[0029] In the present embodiment, the water-retaining ceramsite products prepared from coal gangue materials are mainly used for coal mining subsidence area treatment and soil desertification improvement. Compared with traditional ceramsite, the water-retaining ceramsite has the characteristics of more pores and higher water absorption rate (more than 25%). The fine pores inside the water-retaining ceramsite can accelerate the capillary phenomenon of the ceramsite itself, absorb and store water in a short time, and the excess water is discharged through the pores between the water-retaining ceramsite particles. The water-retaining performance of the water-retaining ceramsite is 4 to 5 times that of traditional ceramsite.

[0030] In the present embodiment, the particle size of the coal gangue is the maximum diameter thereof.

[0031] In the embodiment, the first preset range is 30mm to 100mm; the second preset range is less than 8mm; the third preset range is 10mm to 16mm; the fourth preset range is greater than 100mm; the fifth preset range is less than 30mm; the sixth preset range is 50 to 100 mesh; the first preset value is 400mm; the second preset value is 450mm; the third preset value is 50mm; the first preset temperature is 180℃; the second preset temperature is 900℃; the third preset temperature is 300℃; and the first preset heat value is 300 to 3000 large calories.

[0032] In order to prepare the coal gangue material before processing and perfecting, the method for screening the coal gangue material includes: putting the coal gangue material into the first vibrating screen 10 for the first screening to obtain the coal gangue raw material with the particle size values of the first preset range, the fourth preset range and the fifth preset range; collecting the coal gangue raw material with the particle size values of the fourth preset range and putting it into the first crusher 20 to crush it to the coal gangue raw material with the particle size values in the first preset range and the fifth preset range by the first crusher 20; and putting the coal gangue raw material with the particle sizes in the first preset range and the fifth preset range after the crushing by the first crusher 20 into the second vibrating screen 30 for the second screening to obtain the coal gangue raw material with the particle size values in the first preset range and the fifth preset range. The above method puts the coal gangue material into the double-layer first vibrating screen 10 with the aperture of 30mm and 100mm to obtain the coal gangue raw material with the particle size values of less than 30mm, 30mm to 100mm and greater than 100mm; wherein the coal gangue raw material with the particle size values of 30mm to 100mm is most suitable for making gravel; the coal gangue raw material with the particle size values greater than 100mm is collected to be crushed to the coal gangue raw material with the particle size values less than 100mm by the first crusher 20, and the coal gangue raw material with the particle size values less than 100mm is put into the second vibrating screen 30 with the aperture of 30mm to screen and obtain the coal gangue raw material with the particle size values of less than 30mm and 30mm to 100mm, so as to realize the pretreatment of the coal gangue material.

[0033] Further, the method for screening the coal gangue material further comprises: placing the coal gangue raw material with the particle size value in the first preset range obtained after the two screenings into the dry separator 40 for separation, so as to obtain the coal gangue raw material suitable for making gravel as the gravel raw material through the dry separator 40; collecting the coal gangue raw material unsuitable for making gravel and having the particle size value in the first preset range and the coal gangue raw material having the particle size value in the fifth preset range after the two screenings, and placing the collected coal gangue raw material into the second crusher 50 for crushing, so as to crush the coal gangue raw material to the coal gangue raw material with the particle size value in the second preset range through the second crusher 50, and use the coal gangue raw material as the water-retaining ceramic raw material. The above method screens out the small fine particles and the rough stones mixed in the coal gangue raw material with the particle size value of 30 mm to 100 mm through the dry separator 40, so as to obtain the coal gangue raw material suitable for making gravel, and place the coal gangue raw material into the gravel raw material warehouse for use; collect the coal gangue raw material with the particle size value less than 30 mm after the two screenings and the coal gangue raw material unsuitable for making gravel after the screening through the dry separator 40, crush the coal gangue raw material to the coal gangue raw material with the particle size value less than 8 mm through the second crusher 50, and place the coal gangue raw material into the water-retaining ceramic raw material warehouse for use, and then make the water-retaining ceramic semi-finished product, so as to solve the problem of waste caused by directly discarding the part of the coal gangue unsuitable for making gravel after the screening in the prior art.

[0034] As shown in Figure 1 The method for making the water-retaining ceramic semi-finished product from the water-retaining ceramic raw material comprises: placing the water-retaining ceramic raw material in the buffer bin 60, continuously feeding the vertical mill 62 with the water-retaining ceramic raw material through the feeder 61, and grinding the water-retaining ceramic raw material with the particle size value in the second preset range to the water-retaining ceramic raw material with the fineness value in the sixth preset range through the vertical mill 62, so as to make the water-retaining ceramic semi-finished product from the water-retaining ceramic raw material with the fineness value in the sixth preset range. The above method mainly ensures that the vertical mill 62 is stably operated, and the feeder 61 continuously and stably supplies the water-retaining ceramic raw material to the vertical mill 62, so as to grind the water-retaining ceramic raw material with the particle size value less than 8 mm to the water-retaining ceramic raw material with the fineness value of 50 mesh to 100 mesh through the vertical mill 62. The vertical mill 62 is also provided with auxiliary equipment such as the micro-powder collector and the batching bin, and the coal gangue powder with the fineness value of 50 mesh to 100 mesh is collected for making the water-retaining ceramic semi-finished product.

[0035] Further, the method for manufacturing the water-retaining ceramicite semi-product from the water-retaining ceramicite raw material further comprises: conveying the water-retaining ceramicite raw material with the fineness value in the sixth preset range into the mixing machine 63, adding the pore-forming agent into the mixing machine 63, mixing the water-retaining ceramicite raw material with the fineness value in the sixth preset range and the pore-forming agent at a preset ratio, and conveying the mixed raw material into the balling machine 64 to manufacture the water-retaining ceramicite semi-product by the balling machine 64. In the above method, the coal gangue powder with the fineness value of 50-100 mesh and the pore-forming agent are conveyed into the mixing machine 63 by the rubber belt machine at a preset ratio of 1:3 or 1:7 or 1:9, and the mixed coal gangue powder and pore-forming agent are sent into the balling machine 64 after further humidification for balling. The water-retaining ceramicite has strict requirements for the balling time of the balling machine 64, the rotation speed of the ball disc, the incoming material humidity and the ratio. The water-retaining ceramicite semi-product with the particle size value of 10-16 mm is obtained and stored for use. The manufactured water-retaining ceramicite semi-product is required to have a certain drop strength (not broken after falling 5 times from a height of 1 meter), and the unqualified water-retaining ceramicite semi-product is re-conveyed into the balling machine 64 for balling.

[0036] As shown in Figure 2 In order to mix and sinter the gravel raw material and the water-retaining ceramicite semi-product to obtain the gravel product and the water-retaining ceramicite product, the coal gangue mixing and sintering method further comprises: mixing the water-retaining ceramicite semi-product (with the particle size value of 10-16 mm) and the gravel raw material (with the particle size value of 30-100 mm), and dividing them into two parts placed on the first material layer with the first preset thickness and the second material layer with the second preset thickness respectively; arranging the bottom material on the third material layer with the third preset thickness, and stacking the first material layer, the second material layer and the third material layer in the direction from top to bottom to obtain the sintering raw material, and conveying the sintering raw material into the sintering machine 70 for sintering to obtain the gravel product and the water-retaining ceramicite product.

[0037] In the embodiment, the mixed water-retaining ceramicite semi-product and the gravel raw material are placed on the first material layer and the second material layer with the thicknesses of 400 mm and 450 mm respectively, the bottom material is placed on the third material layer with the thickness of 50 mm, and the mixed water-retaining ceramicite semi-product and the gravel raw material are conveyed into the sintering machine 70 for mixing and sintering to obtain the gravel product and the water-retaining ceramicite product.

[0038] In the first embodiment of the present application, the coal gangue mixing and sintering method further comprises: placing the water-retaining ceramicite semi-product and the gravel raw material on the first material layer and the second material layer with the thicknesses of 400 mm and 450 mm respectively, placing the bottom material on the third material layer with the thickness of 50 mm at the bottom, and conveying the mixed water-retaining ceramicite semi-product and the gravel raw material into the sintering machine 70 for mixing and sintering to obtain the gravel product and the water-retaining ceramicite product.

[0039] Further, the method of transporting the raw material to be fired into the sintering machine 70 for firing includes: transporting the raw material to be fired into the ignition drying area 71 of the sintering machine 70 to complete the ignition drying and water removal process of the water-retaining ceramic semi-finished product and gravel raw material; transporting the dried raw material to be fired into the preheating decarburization area 72 of the sintering machine 70 to calcine the water-retaining ceramic semi-finished product and gravel raw material; transporting the calcined raw material to be fired into the cooling area 73 of the sintering machine 70 to cool it to obtain gravel finished product and water-retaining ceramic finished product; wherein the temperature of the ignition drying area 71 is at a first preset temperature, the temperature of the preheating decarburization area 72 is at a second preset temperature, and the temperature of the cooling area 73 is at a third preset temperature; the first preset temperature is less than the second preset temperature and greater than the third preset temperature.

[0040] The above method transports the raw material to be fired into the ignition drying area 71, the preheating decarburization area 72 and the cooling area 73 of the sintering machine 70 in sequence for mixed firing (at this time the water-retaining ceramic semi-finished product plays a more role as fuel) is an economically feasible method. The temperature of the ignition drying area 71 is about 180°C, mainly for ignition drying of the raw material to be fired, and removing water from the raw material; the temperature of the preheating decarburization area 72 is about 900°C, which can promote the dehydration activation of clay minerals in coal gangue after calcination, thereby dissolving more nutrients such as silicon, calcium, iron, magnesium, sodium, potassium and phosphorus, and also oxidizing excessive pyrite and other minerals in the calcination process to release excess sulfur elements in the form of sulfur oxide gas; at the same time, the calcination process also reduces the inert elements such as carbon, changes the internal micropore channels of the coal gangue, and is beneficial to the retention and slow release of the nutrient composition of the coal gangue, and increases the compressive strength of the raw material. The additional heat required for the firing of the gravel raw material and the water-retaining ceramic semi-finished product is provided by natural gas, and the natural gas burner is installed in the preheating decarburization area 72; the temperature of the cooling area 73 is about 300°C, which cools the calcined gravel raw material and water-retaining ceramic semi-finished product to obtain gravel finished product and water-retaining ceramic finished product.

[0041] Further, the coal gangue mixed firing method further includes discharging heat from the preheating decarburization area 72 to maintain the temperature of the preheating decarburization area 72 at the second preset temperature. The above method controls the firing temperature of the gravel raw material and the water-retaining ceramic semi-finished product to about 900°C, and the additional heat required for firing is provided by natural gas, and the natural gas burner is installed in the preheating decarburization area 72. By setting a fan in the preheating decarburization area 72, the residual heat of the high calorific value coal gangue during the heating and calcination process is discharged by the fan to achieve temperature control of the gravel raw material and the water-retaining ceramic semi-finished product during the mixed firing process, which breaks through the limitation of traditional rotary kiln or sintered brick that cannot use high calorific value (greater than 300 kcal / kg) coal gangue in large amounts.

[0042] Specifically, the coal gangue mixed firing method further comprises discharging high-temperature gas located in the sintering machine 70 to utilize the discharged high-temperature gas for waste heat power generation treatment. The above method, the waste heat utilization system comprises a waste heat boiler, a steam extraction condensing steam turbine and a generator set, mainly utilizing the waste heat released by the gravel raw materials and the water-retaining ceramic aggregate semi-finished product in the mixed firing process to generate superheated steam (pressure 5.3 MPa, temperature 485 DEG C) into a superheated steam main pipe for steam turbine power generation. The waste heat output by the gravel raw materials and the water-retaining ceramic aggregate semi-finished product can be used for heating steam or waste heat power generation, and these waste heat resources not only efficiently utilize the energy properties of coal gangue, but also can be counted as raw material energy according to the national regulations, and the carbon emission and energy consumption are not counted, so the residual carbon burned in the heating process is not counted in the energy consumption and carbon emission, and the output waste heat utilization becomes an important source of negative energy consumption and carbon emission reduction, which makes the mixed firing of gravel and water-retaining ceramic aggregate become a negative energy or carbon emission reduction project because of the utilization of high-calorific-value coal gangue.

[0043] From the above description, it can be seen that the above-mentioned embodiments of the present application achieve the following technical effects:

[0044] The coal gangue mixed firing method comprises pretreating coal gangue materials to screen coal gangue raw materials with different particle sizes, collecting coal gangue raw materials with a particle size value within a first preset range as gravel raw materials; collecting coal gangue raw materials with a particle size value within a second preset range and a heat value reaching a first preset heat value as water-retaining ceramic aggregate raw materials, and preparing water-retaining ceramic aggregate semi-finished products with a particle size value within a third preset range; mixing and firing the gravel raw materials and the water-retaining ceramic aggregate semi-finished products, and screening after the mixed firing to obtain gravel finished products and water-retaining ceramic aggregate finished products; wherein the value of the first preset range is greater than the value of the second preset range. The above method screens coal gangue materials with different particle size values to obtain coal gangue raw materials with a particle size value within a first preset range as gravel raw materials to prepare gravel; at the same time, coal gangue raw materials with a particle size value not within the first preset range are collected to prevent waste and are crushed and screened to further obtain coal gangue raw materials with a particle size value within the first preset range and not within the first preset range, and coal gangue raw materials not within the first preset range and with a first preset heat value are collected and crushed to obtain coal gangue raw materials with a particle size value within a second preset range as water-retaining ceramic aggregate raw materials to prepare water-retaining ceramic aggregate semi-finished products with a particle size value within a third preset range; the gravel raw materials and the prepared water-retaining ceramic aggregate semi-finished products are mixed and fired to obtain gravel finished products and water-retaining ceramic aggregate finished products, to solve the problem of waste caused by directly discarding part of the coal gangue not suitable for making gravel after screening in the prior art.

[0045] It is to be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments in accordance with the present application. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms "comprises" and / or "comprising," when used in this specification, specify the presence of stated features, steps, operations, devices, components and / or combinations thereof, but do not preclude the presence or addition of one or more other features, steps, operations, devices, components and / or combinations thereof.

[0046] The relative arrangement of components and steps, numerical expressions, and numerical values set forth in the examples are not intended to limit the scope of the application unless otherwise specifically stated. It is to be understood that the drawings are not necessarily to scale of the various parts shown in the drawings. Techniques, methods, and apparatus known to those of ordinary skill are not discussed in detail because they would be understood that such techniques, methods, and apparatus are considered part of the art. In all examples shown and discussed herein, any specific values are to be interpreted as merely illustrative and not limiting. Thus, other examples of the example embodiments can have different values. It is noted that like numbers and letters on the figures identify like parts throughout the several views, and thus, once an item is defined in one figure, it is not necessary to discuss it further in connection with other figures where it is understood that the item will be present.

[0047] In the description of the present application, it is to be understood that the orientation or positional relationships indicated by terms such as "front", "back", "up", "down", "left", "right", "lateral", "vertical", "horizontal", and "top", "bottom" are generally based on the orientation or positional relationships shown in the drawings, and are merely for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation or be constructed and operated in a particular orientation, and therefore should not be construed as limiting the scope of protection of the present application. The orientation terms "inner", "outer" refer to the inner and outer relative to the contour of the components themselves.

[0048] For purposes of the description hereinafter, spatial or directional terms, for example, "above", "below", "upper", "lower", and the like, can be used, and relate to the device as illustrated in the figures. However, it is to be understood that no absolute or relative orientation of the device is intended or implied, unless specifically described as such. Terms concerning attachments, coupling and the like, such as "connected" and "coupled" and the like, are to be construed in accordance with their normal meanings, that is, as referring to an indirect or direct connection or coupling. Any reference to "comprising" or "containing" is to be construed as meaning "comprising or containing, but not limited to". Any reference to "comprising" or "containing" is to be construed as meaning "comprising or containing, but not limited to".

[0049] In addition, it should be pointed out that the use of the terms "first", "second" and the like, to describe various elements, is merely intended to differentiate the elements from one another, and does not connote any special order or order of precedence, unless otherwise specifically indicated. Thus, the use of the terms "first", "second" and the like, is not intended to limit the scope of the present application, and is not intended to connote any special order or order of precedence.

[0050] The preferred embodiments herein disclosed are not to be construed as limiting, and the scope of the protection is defined by the appended claims.

Claims

1. A method for coking coal gangue, characterized in that, include: The coal gangue material is pretreated to screen coal gangue raw materials with different particle sizes, and coal gangue raw materials with particle sizes that meet the first preset range are collected as gravel raw materials. Coal gangue raw materials with particle size values ​​within the second preset range and calorific value reaching the first preset calorific value are collected as raw materials for water-retaining ceramsite and processed into water-retaining ceramsite semi-finished products with particle size values ​​within the third preset range. The gravel raw material and the water-retaining ceramsite semi-finished product are mixed and fired, and then screened after mixing and firing to obtain the gravel finished product and the water-retaining ceramsite finished product. Wherein, the value of the first preset range is greater than the value of the second preset range; The coal gangue material is placed into the first vibrating screen (10) for the first screening to obtain coal gangue raw materials with particle size values ​​of the first preset range, the fourth preset range and the fifth preset range respectively; Collect coal gangue raw materials with particle size values ​​within the fourth preset range and put them into the first crusher (20) to crush them into coal gangue raw materials with particle size values ​​within the first preset range and the fifth preset range, respectively. Coal gangue raw materials with particle sizes within the first preset range and the fifth preset range after being crushed by the first crusher (20) are placed into the second vibrating screen (30) for a second screening to obtain coal gangue raw materials with particle sizes within the first preset range and the fifth preset range, respectively. The water-retaining ceramsite semi-finished product and the gravel raw material are mixed and divided into two parts, which are respectively placed on a first fabric layer with a thickness of a first preset value and a second fabric layer with a thickness of a second preset value. The first preset range is 30mm to 100mm; the second preset range is less than 8mm. The first preset value is 400mm; The third preset range is 10mm to 16mm; The fourth preset range is greater than 100mm; the fifth preset range is less than 30mm.

2. The method for coking coal gangue according to claim 1, characterized in that, The method for screening the coal gangue material further includes: The coal gangue raw material with a particle size within the first preset range obtained after two screenings is put into a dry separator (40) for sorting, so that the coal gangue raw material suitable for making gravel obtained by the dry separator (40) is used as gravel raw material. Collect coal gangue raw materials that are unsuitable for gravel production and whose particle size is within the first preset range, obtained by the dry separator (40), and coal gangue raw materials whose particle size is within the fifth preset range after two screenings. Put the collected coal gangue raw materials into the second crusher (50) for crushing, so that the coal gangue raw materials with a particle size within the second preset range are crushed by the second crusher (50) to be used as the water-retaining ceramsite raw material.

3. The method for coking coal gangue according to claim 2, characterized in that, The method for preparing the water-retaining ceramsite raw material into the water-retaining ceramsite semi-finished product includes: The water-retaining ceramsite raw material is placed in a buffer hopper (60), and the feeder (61) continuously feeds it to the vertical mill (62) so that the water-retaining ceramsite raw material with a particle size within the second preset range is ground into water-retaining ceramsite raw material with a fineness within the sixth preset range by the vertical mill (62) so as to produce the water-retaining ceramsite semi-finished product by using the water-retaining ceramsite raw material with a fineness within the sixth preset range.

4. The method for coking coal gangue according to claim 3, characterized in that, The method for preparing the water-retaining ceramsite raw material into the water-retaining ceramsite semi-finished product further includes: The water-retaining ceramsite raw material with a fineness value within the sixth preset range is transported to the mixer (63), and a pore-forming agent is added to the mixer (63) to mix the water-retaining ceramsite raw material with a fineness value within the sixth preset range and the pore-forming agent in a preset ratio. The mixed raw material is then transported to the pelletizer (64) to be processed into the water-retaining ceramsite semi-finished product by the pelletizer (64).

5. The method for coking coal gangue according to claim 1, characterized in that, The coal gangue mixing and calcination method further includes: The base material is arranged on the third fabric layer with a thickness of the third preset value, and the first fabric layer, the second fabric layer and the third fabric layer are stacked in sequence from top to bottom to obtain the raw material to be fired. The raw material to be fired is transported to the sintering machine (70) for firing to obtain gravel product and water-retaining ceramsite product.

6. The method for coking coal gangue according to claim 5, characterized in that, The method of transporting the raw material to be fired into the sintering machine (70) for firing includes: The raw materials to be fired are transported to the ignition drying zone (71) of the sintering machine (70) to complete the process of ignition drying and dehydration of the water-retaining ceramsite semi-finished product and the gravel raw materials. The dried raw materials to be fired are transported to the preheating and decarburization zone (72) of the sintering machine (70) to calcine the water-retaining ceramsite semi-finished product and the gravel raw material; The calcined raw material to be calcined is transported to the cooling zone (73) of the sintering machine (70) to cool it down, so as to obtain the gravel product and the water-retaining ceramsite product. The temperature of the ignition drying zone (71) is at a first preset temperature, the temperature of the preheating decarburization zone (72) is at a second preset temperature, and the temperature of the cooling zone (73) is at a third preset temperature; the first preset temperature is less than the second preset temperature and greater than the third preset temperature.

7. The method for coking coal gangue according to claim 6, characterized in that, The coal gangue mixing and calcination method further includes: Heat located in the preheating decarburization zone (72) is discharged to maintain the temperature of the preheating decarburization zone (72) at the second preset temperature.

8. The method for coking coal gangue according to claim 6, characterized in that, The coal gangue mixing and calcination method further includes: The high-temperature gas located in the sintering machine (70) is discharged to utilize the discharged high-temperature gas for waste heat power generation.

9. The method for coking coal gangue according to claim 4, characterized in that, The sixth preset range is 50 mesh to 100 mesh.

10. The method for coking coal gangue according to claim 5, characterized in that, The second preset value is 450mm; the third preset value is 50mm.

11. The method for coking coal gangue according to claim 6, characterized in that, The first preset temperature is 180℃; the second preset temperature is 900℃; and the third preset temperature is 300℃.

12. The method for coking coal gangue according to claim 1, characterized in that, The first preset calorific value is 300 kcal to 3000 kcal.

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