Active wall body purification method based on coal gangue solid waste

Abstract

The invention provides an active wall body purification method based on coal gangue solid waste, and relates to the technical field of coal gangue solid waste. The active wall body purification method based on the coal gangue solid waste specifically comprises the following steps: S1, raw material pretreatment; s2, loading a catalyst; s3, high-temperature calcination; and S4, wall body purification unit construction. In the aspect of environmental protection, coal gangue solid waste is efficiently utilized, the problems of pollution and waste are solved, the purpose of treating pollution with waste is achieved, in the process aspect, wet catalyst loading and segmented calcination enable a photocatalyst to be evenly attached to ceramsite, a through pore structure enhances the purification effect and stability, the material performance is good, and compared with a traditional filter material, the ceramsite is high in strength and large in specific surface area; the modular wall body purification unit has the advantages of wear resistance, long service life, low cost, flexible application, low energy consumption, simplicity in operation, no secondary pollution and economic and social benefits, and the modular wall body purification unit is suitable for various building scenes.

Description

Technical Field

[0001] The present invention relates to the technical field of coal gangue solid waste, in particular to an active wall purification method based on coal gangue solid waste. Background Art

[0002] Gangue solid waste is solid waste generated during coal mining and washing. Composed primarily of carbonaceous shale, mudstone, sandstone, and other rocks, it is a dark-gray rock with a low carbon content and harder than coal. It is produced during coal mine construction, tunneling, coal mining, and coal washing, and its emissions generally account for 10%-20% of coal production. Long-term open-air storage of gangue not only occupies significant land but also generates dust and leaching water due to weathering and rain, polluting the atmosphere, soil, and water. The heavy metals and other hazardous substances it contains can harm the ecological environment and human health. However, after processing, gangue can be used as a resource in various applications, including building material production, power generation, and land reclamation.

[0003] Currently, the main wall material used on the market is ceramsite, a filter material primarily made from shale, clay, and sludge. The production of shale ceramsite requires the exploitation of mineral resources, and this large-scale mining activity can have a certain impact on the surrounding ecological environment, such as destroying mountain vegetation and causing soil erosion. While clay ceramsite is widely used, it suffers from poor pressure resistance. Over long-term use, it is prone to fracture when subjected to certain pressures, which in turn affects the overall stability and service life of the wall. Sludge ceramsite, on the other hand, has low compressive strength and may not maintain its physical properties well under high pressure, resulting in a decrease in wall performance. Furthermore, coal gangue, as a solid waste, can cause serious environmental pollution and damage if not properly handled. Its storage not only occupies a large amount of land but can also spontaneously combust, releasing harmful gases such as sulfur dioxide. The leachate from this can also contaminate soil and groundwater. Therefore, the present invention proposes an active wall purification method based on coal gangue solid waste, aiming to solve the many problems caused by the above-mentioned traditional wall materials and coal gangue treatment. Summary of the Invention

[0004] In view of the shortcomings of the existing technology, the present invention provides an active wall purification method based on coal gangue solid waste, which solves the problems of high resource loss and poor performance in the existing technology.

[0005] To achieve the above objectives, the present invention is implemented through the following technical solutions: an active wall purification method based on coal gangue solid waste, specifically comprising the following steps:

[0006] S1. Raw material pretreatment

[0007] The gangue is crushed to a particle size of ≤5mm, mixed with yellow mud, iron powder and additives in a mass ratio of (60-65):(30-35):(0.5-1):(0.1-0.15), water is added to adjust the moisture content to 12% to 18%, and granulated into raw material balls;

[0008] S2. Catalyst loading

[0009] While the surface of the raw material ball is kept moist, titanium dioxide photocatalyst is evenly sprayed into the ball forming plate, with the addition amount being 10% to 15% of the total mass of the raw material ball, so that the catalyst is adsorbed on the surface of the pores of the raw material ball;

[0010] S3. High temperature calcination

[0011] The catalyst-loaded raw material balls are placed in a double-drum rotary kiln and processed through four stages: drying, preheating, sintering at a constant temperature of 1100°C, and cooling. The sintering time is ≥ 60 minutes to form a porous ceramsite carrier.

[0012] S4. Construction of wall purification unit

[0013] The obtained ceramsite is filled into a breathable container and arranged at intervals on the wall surface or in the interlayer at a density of 0.5 to 1 kg of ceramsite per cubic meter of space, so as to purify air pollutants through the adsorption-photocatalytic synergistic effect of the ceramsite.

[0014] Preferably, the catalyst injection in step S2 must meet the following requirements:

[0015] Compressed gas is used to blow titanium dioxide powder into the ball-forming disk;

[0016] The injection rate is controlled at 100-200 g / min to ensure that the catalyst forms a uniform film-like shell on the surface of the raw material ball;

[0017] During the spraying process, the rotation speed of the ball forming disc is 15-25 rpm to maintain the integrity of the raw material balls.

[0018] Preferably, the calcination process of step S3 includes:

[0019] Drying stage: temperature 150-250℃, duration 10-15 minutes;

[0020] Preheating stage: temperature 450-600℃, duration 15-20 minutes;

[0021] Constant temperature firing stage: 1100℃±20℃, duration ≥30 minutes;

[0022] Cooling stage: forced air cooling to below 80℃.

[0023] Preferably, the step S1 specifically includes:

[0024] The gangue is coarsely crushed, dried, and ground to less than 200 mesh in a vertical mill;

[0025] The mixed raw materials were homogenized in a powerful blender for ≥20 minutes;

[0026] The pelletizing process uses a ball-forming disc and the particle size of the raw material balls is controlled at 3 to 8 mm.

[0027] Preferably, the container in step S4 is:

[0028] Porous ceramic box or light-transmitting mesh module;

[0029] Set up 3 to 5 independent purification units per square meter of wall area;

[0030] The unit spacing is 20 to 50 cm, forming a detachable connection structure with the wall.

[0031] Preferably, the target pollutants to be purified in the method include: volatile organic compounds (VOCs), nitrogen oxides (NOx), suspended particulate matter (PM2.5 / PM10), and formaldehyde.

[0032] The present invention provides an active wall purification method based on coal gangue solid waste. It has the following beneficial effects:

[0033] The present invention provides an active wall purification method based on coal gangue solid waste. The present invention solves the traditional solid waste treatment problems through efficient resource utilization of coal gangue solid waste, avoids environmental pollution and waste of resources, achieves the purpose of "using waste to treat pollution", and has outstanding environmental benefits. The process of the present invention is advanced and unique, and the wet catalyst loading is combined with staged calcination to make the photocatalyst uniformly adsorbed on the surface of the expanded clay to form a pore-through structure, thereby enhancing the catalyst adhesion and pollutant retention capacity, and ensuring a stable and long-lasting purification effect. The material prepared by the present invention has excellent performance. Compared with traditional filter materials, the coal gangue expanded clay has high mechanical strength, large specific surface area, strong wear resistance and crushing ability, which extends the service life and reduces operation and maintenance costs. The application of the present invention is flexible and convenient, and the modular design of the wall purification unit is suitable for various building scenes to meet different space requirements. The overall process has low energy consumption, simple operation, and no secondary pollution, and has both economic and social benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 It is a schematic diagram of the process of the present invention. DETAILED DESCRIPTION

[0035] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0036] like Figure 1 As shown, an embodiment of the present invention provides an active wall purification method based on coal gangue solid waste, which specifically includes the following steps:

[0037] S1. Raw material pretreatment

[0038] The gangue is crushed to a particle size of ≤5mm, mixed with yellow mud, iron powder and additives in a mass ratio of (60-65):(30-35):(0.5-1):(0.1-0.15), water is added to adjust the moisture content to 12% to 18%, and granulated into raw material balls;

[0039] S2. Catalyst loading

[0040] While the surface of the raw material ball is kept moist, titanium dioxide photocatalyst is evenly sprayed into the ball forming plate, with the addition amount being 10% to 15% of the total mass of the raw material ball, so that the catalyst is adsorbed on the surface of the pores of the raw material ball;

[0041] S3. High temperature calcination

[0042] The catalyst-loaded raw material balls are placed in a double-drum rotary kiln and processed through four stages: drying, preheating, sintering at a constant temperature of 1100°C, and cooling. The sintering time is ≥ 60 minutes to form a porous ceramsite carrier.

[0043] S4. Construction of wall purification unit

[0044] The obtained ceramsite is filled into a breathable container and arranged at intervals on the wall surface or in the interlayer at a density of 0.5 to 1 kg of ceramsite per cubic meter of space, so as to purify air pollutants through the adsorption-photocatalytic synergistic effect of the ceramsite.

[0045] The catalyst injection in step S2 must meet the following requirements:

[0046] Compressed gas is used to blow titanium dioxide powder into the ball-forming disk;

[0047] The injection rate is controlled at 100-200 g / min to ensure that the catalyst forms a uniform film-like shell on the surface of the raw material ball;

[0048] During the spraying process, the rotation speed of the ball forming disc is 15-25 rpm to maintain the integrity of the raw material balls.

[0049] The calcination process of step S3 includes:

[0050] Drying stage: temperature 150-250℃, duration 10-15 minutes;

[0051] Preheating stage: temperature 450-600℃, duration 15-20 minutes;

[0052] Constant temperature firing stage: 1100℃±20℃, duration ≥30 minutes;

[0053] Cooling stage: forced air cooling to below 80℃.

[0054] Step S1 specifically includes:

[0055] The gangue is coarsely crushed, dried, and ground to less than 200 mesh in a vertical mill;

[0056] The mixed raw materials were homogenized in a powerful blender for ≥20 minutes;

[0057] The pelletizing process uses a ball-forming disc and the particle size of the raw material balls is controlled at 3 to 8 mm.

[0058] The container in step S4 is:

[0059] Porous ceramic box or light-transmitting mesh module;

[0060] Set up 3 to 5 independent purification units per square meter of wall area;

[0061] The unit spacing is 20 to 50 cm, forming a detachable connection structure with the wall.

[0062] The target pollutants to be purified in the method include: volatile organic compounds (VOCs), nitrogen oxides (NOx), suspended particulate matter (PM2.5 / PM10) and formaldehyde.

[0063] Table 1 Moisture content and wear rate of the ball:

[0064]

[0065]

[0066] Table 2 Experiment on plasticity and liquefaction critical point of coal gangue ceramsite:

[0067]

[0068]

[0069] This invention aims to address the environmental pollution and damage caused by coal gangue as solid waste, improve its comprehensive utilization, and promote its application in air purification and pollutant decomposition. Through processing, the gangue is converted into ceramsite with a specific pore structure and specific surface area. This ceramsite possesses adsorption and filtration properties, effectively treating pollutants such as ammonia, nitrogen, total phosphorus, and COD in wastewater.

[0070] In terms of technical background, existing filter media, ceramsite, are mostly made from shale, clay, sludge, and other raw materials. These materials present environmental issues, poor pressure resistance, and low strength. This invention overcomes these shortcomings by utilizing coal gangue to produce a high-strength, recyclable material. Specifically, the coal gangue undergoes processes such as crushing, drying, grinding, stirring, granulation, and sintering to form ceramsite with high mechanical strength and specific surface area. This ceramsite is not only suitable for photocatalyst adsorption, but also effectively removes organic matter, suspended matter, and nitrogen oxides from the air.

[0071] The technical solution of this invention details the production process for gangue filter media, including the steps of raw material crushing, drying, grinding, mixing, granulation, and sintering. Through these steps, the gangue is transformed into ceramsite with high strength and excellent adsorption properties. The key lies in the retention of the raw material pellets, a crucial performance indicator during the calcination process and a key technology for using gangue ceramsite as a catalyst-carrying matrix. By adding a photocatalyst at the appropriate stage, the ceramsite's efficient adsorption and filtration properties can be ensured.

[0072] The key point and key point of this invention lies in the use of coal gangue to produce high-strength, high-specific-surface-area ceramsite. This ceramsite exhibits excellent adsorption and filtration properties, effectively removing pollutants from air and wastewater. Furthermore, this invention offers key advantages such as waste-to-waste pollution control, no secondary pollution, strong catalyst adhesion, excellent suspended solids retention, greater strength compared to traditional materials, and a longer service life. These technological innovations not only enhance the comprehensive utilization of coal gangue but also provide effective technical support for achieving environmental protection goals.

[0073] This technology uses coal gangue solid waste as raw material and transforms it into a high-performance active wall purification material through an innovative process, offering significant environmental benefits and technical advantages. First, this technology achieves efficient resource utilization of coal gangue, addressing the environmental pollution and resource waste associated with traditional solid waste treatment, embodying the dual environmental benefits of "using waste to treat pollution." Second, through wet catalyst loading and staged calcination, the photocatalyst is successfully adsorbed evenly onto the surface of the ceramsite, forming a porous carrier structure. This significantly enhances the catalyst's adhesion and pollutant retention capacity, ensuring the stability and durability of the air purification effect. Compared to traditional filter media, coal gangue ceramsite has higher mechanical strength and specific surface area, effectively resisting wear and breakage, extending its service life, and reducing operation and maintenance costs. Furthermore, the modular design of the wall purification unit allows for flexible integration of air purification functions, making it suitable for a variety of building scenarios and meeting the needs of different spaces. The overall process offers low energy consumption, simple operation, and no secondary pollution, resulting in excellent economic and social benefits. In short, this technology not only solves the problem of coal gangue solid waste treatment, but also provides an efficient, environmentally friendly and sustainable solution for the field of air purification, with broad application prospects and market value.

[0074] While embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions, and variations may be made to these embodiments without departing from the principles and spirit of the invention, and that the scope of the invention is defined by the appended claims and their equivalents.

Claims

1. An active wall purification method based on coal gangue solid waste, specifically comprising the following steps, characterized in that: S1. Raw material pretreatment The gangue is crushed to a particle size of ≤5mm, mixed with yellow mud, iron powder and additives in a mass ratio of (60-65):(30-35):(0.5-1):(0.1-0.15), water is added to adjust the moisture content to 12% to 18%, and granulated into raw material balls; S2. Catalyst loading While the surface of the raw material ball is kept moist, titanium dioxide photocatalyst is evenly sprayed into the ball forming plate, with the addition amount being 10% to 15% of the total mass of the raw material ball, so that the catalyst is adsorbed on the surface of the pores of the raw material ball; S3. High temperature calcination The catalyst-loaded raw material balls are placed in a double-drum rotary kiln and processed through four stages: drying, preheating, sintering at a constant temperature of 1100°C, and cooling. The sintering time is ≥ 60 minutes to form a porous ceramsite carrier. S4. Construction of wall purification unit The obtained ceramsite is filled into a breathable container and arranged at intervals on the wall surface or in the interlayer at a density of 0.5 to 1 kg of ceramsite per cubic meter of space, so as to purify air pollutants through the adsorption-photocatalytic synergistic effect of the ceramsite.

2. The active wall purification method based on coal gangue solid waste according to claim 1, characterized in that: The catalyst injection in step S2 must meet the following requirements: Compressed gas is used to blow titanium dioxide powder into the ball-forming disk; The injection rate is controlled at 100-200 g / min to ensure that the catalyst forms a uniform film-like shell on the surface of the raw material ball; During the spraying process, the rotation speed of the ball forming disc is 15-25 rpm to maintain the integrity of the raw material balls.

3. The active wall purification method based on coal gangue solid waste according to claim 1, characterized in that: The calcination process of step S3 includes: Drying stage: temperature 150-250℃, duration 10-15 minutes; Preheating stage: temperature 450-600℃, duration 15-20 minutes; Constant temperature firing stage: 1100℃±20℃, duration ≥30 minutes; Cooling stage: forced air cooling to below 80℃.

4. The active wall purification method based on coal gangue solid waste according to claim 1, characterized in that: The step S1 specifically includes: The gangue is coarsely crushed, dried, and ground to less than 200 mesh in a vertical mill; The mixed raw materials were homogenized in a powerful blender for ≥20 minutes; The pelletizing process uses a ball-forming disc and the particle size of the raw material balls is controlled at 3 to 8 mm.

5. The active wall purification method based on coal gangue solid waste according to claim 1, characterized in that: The container in step S4 is: Porous ceramic box or light-transmitting mesh module; Set up 3 to 5 independent purification units per square meter of wall area; The unit spacing is 20 to 50 cm, forming a detachable connection structure with the wall.

6. The active wall purification method based on coal gangue solid waste according to claim 1, characterized in that: The target pollutants purified in the method include: volatile organic compounds (VOCs), nitrogen oxides (NOx), suspended particulate matter (PM2.5 / PM10), and formaldehyde.

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