Preparation method of environment-friendly cementitious material suitable for coal briquette bonding

Abstract

The present application relates to the technical field of cemented filling body, and discloses a preparation method of environment-friendly cementing material suitable for coal block cementing, 1) coal gangue is placed in a washing machine to form clean material; the washing machine comprises a machine body, the machine body is provided with a washing cavity, the top of the washing cavity is provided with a feeding port, the bottom of the washing cavity is provided with an up-and-down swinging discharge plate, the bottom of the washing cavity is provided with a liquid outlet, and the liquid outlet is provided with a filter screen; washing liquid enters the washing cavity through a liquid inlet on the machine body, the washing liquid flushes the coal gangue in the washing cavity and carries the impurities on the surface of the coal gangue out of the washing cavity through the liquid outlet, and then the discharge port is opened for discharging by swinging the discharge plate; 2) the clean material is crushed to form crushed material; 3) the crushed material is screened through a screening machine, and then dried to obtain fine gangue; 4) the fine gangue, slag, gypsum, fly ash, clinker and steel slag powder are loaded into a ball mill for ball grinding to form powder; and 5) the powder is uniformly mixed to form the environment-friendly cementing material.

Description

Technical Field

[0001] This invention patent relates to the technical field of cemented filling materials, and more specifically, to a method for preparing environmentally friendly cementing materials suitable for coal block cementation. Background Technology

[0002] Coal lumps, as aggregates in cemented backfill, significantly influence the strength of the backfill. Generally, the hardness of aggregates is positively correlated with the strength of cemented backfill. The raw coal, one of the main research subjects in this project, has a strength of 25-35 MPa, corresponding to a hardness f-value of 2.5-3.5, while conventional concrete aggregates, such as limestone and granite, have f-values ​​exceeding 8. Therefore, coal lumps are not advantageous as aggregates for backfill; high-strength, high-bonding cementitious materials are needed to match them in order to prepare cementing materials that meet the support requirements. Summary of the Invention

[0003] The purpose of this invention is to provide a method for preparing environmentally friendly cementitious materials suitable for coal briquette bonding, aiming to solve the problem in the prior art that the strength of cemented backfill is difficult to guarantee when coal briquette is used as aggregate in cemented backfill.

[0004] This invention is achieved through a method for preparing an environmentally friendly cementing material suitable for coal briquettes, comprising the following preparation steps:

[0005] 1) Coal gangue is placed in a washing machine for washing to form clean material; the washing machine includes a machine body, the machine body has a washing chamber, the top of the washing chamber is provided with a feed port, the bottom of the washing chamber is provided with a discharge plate that swings up and down, the discharge plate is covered on the discharge port, the bottom of the washing chamber is provided with a liquid outlet, and a filter screen is provided on the liquid outlet.

[0006] The cleaning fluid enters the cleaning chamber through the inlet on the machine body. The cleaning fluid washes the coal gangue in the cleaning chamber and carries the impurities on the surface of the coal gangue out through the outlet. Then, the discharge plate is swung to open the discharge port, and the clean material rolls downward through the discharge port.

[0007] 2) The cleaned material is crushed to form crushed material;

[0008] 3) The crushed material is screened by a screening machine and then dried to obtain fine gangue;

[0009] 4) The fine gangue, slag, gypsum, fly ash, clinker, and steel slag powder are fed into a ball mill and ball-milled to form powder.

[0010] 5) Mix the powder evenly to form the environmentally friendly cementitious material.

[0011] Optionally, the middle part of the cleaning chamber is provided with a vibrating rod that reciprocates up and down. The bottom of the vibrating rod extends downward to the lower part of the cleaning chamber to form a bottom section. Multiple radially outwardly expanding vibrating disks are formed on the outer periphery of the bottom section. The multiple vibrating disks are arranged at intervals up and down along the height direction of the bottom section. There is an annular gap between the outer periphery of the vibrating disk and the side wall of the cleaning chamber. The top of the vibrating disk forms a vibration surface.

[0012] In step 1), during the process of washing the coal gangue with the cleaning fluid, the vibrating rod vibrates up and down, the coal gangue on the vibrating surface vibrates up and down, and adjacent coal gangue rub against each other, causing impurities on the surface of the coal gangue to fall off.

[0013] Optionally, the vibrating surface is arranged to extend downwards at an angle from the inside out along the radial direction of the vibratory plate;

[0014] In step 1), when the discharge port is open, the clean material on the vibrating surface rolls downward along the inclined direction of the vibrating surface.

[0015] Optionally, the cleaning chamber has a circumferential inner peripheral wall, on which a plurality of external water spray heads are provided. The plurality of external water spray heads are arranged at intervals along the circumferential direction of the inner peripheral wall to form an external water spray ring. The plurality of external water spray rings are arranged at intervals along the height direction of the inner peripheral wall.

[0016] In step 1), the external water spray head sprays the cleaning fluid toward the center of the cleaning chamber.

[0017] Optionally, a plurality of internal water spray holes are formed on the outer periphery of the vibrating rod, the plurality of internal water spray holes are arranged at intervals along the circumference of the vibrating rod to form an internal water spray ring, and the plurality of internal water spray rings are arranged at intervals along the height direction of the vibrating rod.

[0018] In step 1), the inner water spray hole sprays the cleaning fluid toward the inner peripheral wall.

[0019] Optionally, an elastic membrane layer is provided on the outer side of the inner water spray hole, and the middle part of the elastic membrane layer covers the inner water spray hole; an elastic region is formed between the elastic membrane layer and the outer periphery of the vibrating rod, and a plurality of membrane holes are provided on the elastic membrane layer, which are staggered on the elastic membrane layer; a plurality of upwardly protruding elastic strips are provided on the vibrating plate, the top of the elastic strips forming an abutting end, and the plurality of elastic strips are aligned with the respective plurality of elastic membrane layers;

[0020] In step 1), as the inner water spray hole sprays cleaning fluid toward the elastic region, the elastic region expands and deforms outward, and the middle part of the elastic membrane layer bulges outward to form a protrusion. The outer surface of the protrusion squeezes the coal gangue on the vibrating plate, the membrane hole expands and deforms outward, and multiple membrane holes spray water in multiple directions toward the outer side of the elastic membrane layer. The elastic strip vibrates and deforms with the up-and-down vibration of the vibrating plate, and the abutting end repeatedly presses against the protrusion, causing the cleaning fluid in the elastic region to spray outward through the membrane hole.

[0021] Optionally, in step 3), the crushed material is screened to form coarse material larger than the set particle size and fine material smaller than the set particle size, and the fine material is dried in a drying oven to form fine-grained gangue.

[0022] Optionally, the drying oven includes a box body, the box body has a drying chamber, the drying chamber is provided with a heat-conducting plate made of metal, the heat-conducting plate has a plate cavity, the drying chamber is provided with an air outlet, and the air outlet is arranged facing the plate cavity;

[0023] In step 3), the fine material is placed in the disc cavity, and the air outlet dries the fine material with hot air until the fine material is completely dry, forming fine-grained gangue.

[0024] Optionally, push plates that move toward each other or away from each other are respectively provided on both sides of the bottom of the drying chamber, and the push plates are connected to moving rods that move back and forth; the push plates are arranged laterally in the drying chamber, and the bottom of the push plates presses against the bottom of the drying chamber. Each of the two push plates has a front pushing surface arranged opposite to each other, and a plate gap is formed between the two front pushing surfaces. The front pushing surfaces extend inward at an inward angle along the direction from bottom to top.

[0025] In step 3), during the drying process of the fine material, when the two push plates move toward each other, the plate gap narrows, and the fine material at the bottom of the plate gap moves upward along the extension direction of the front push surface.

[0026] Optionally, each of the two push plates has a rear push surface arranged opposite to each other. The rear push surface extends inward at an inward angle along the direction from bottom to top, and a surface gap is formed between the rear push surface and the side of the drying chamber.

[0027] In step 3), during the drying process of the fine material, when the two push plates move away from each other, the surface gap narrows, and the fine material on the bottom of the surface gap moves upward along the extension direction of the rear push surface.

[0028] Compared with existing technologies, the present invention provides a method for preparing environmentally friendly cementing materials suitable for coal block bonding. Fine-grained gangue is ground and mixed with slag, gypsum, fly ash, clinker, and steel slag powder in a certain proportion to form a cementing material for preparing environmentally friendly coal block cemented backfill. This method realizes the utilization of solid waste. By grinding the slag, the hydration reaction rate of the slag during the hardening and strength growth process of the shaped coal block cemented backfill is improved.

[0029] The preparation of environmentally friendly coal-bearing cemented backfill utilizes the divalent metal oxides (CaO+MgO+FeO) in steel slag powder to activate the formation of CSH gel in slag and aggregate. With the participation of gypsum, Al2O3 and Fe2O3 in the slag and tailings are extracted to form iron-containing ettringite-like complex salts. These ettringite complex salts form needle-like crystals with nanometer diameters, thus enhancing and toughening the hardened body. Utilizing the activating effect of steel slag powder, desulfurized gypsum powder, and blast furnace water-quenched slag powder, a large number of needle-like complex salt crystals are formed, along with a large amount of near-amorphous CSH gel, tightly encapsulating the needle-like complex salt crystals and significantly improving the stability of the entire system. Therefore, by configuring environmentally friendly cementing materials to use coal lumps as aggregate in the cemented backfill, the strength of the cemented backfill can be guaranteed. Attached Figure Description

[0030] Figure 1 This is a flowchart illustrating the preparation method of environmentally friendly cementing material suitable for coal bridging provided by the present invention.

[0031] Figure 2 This is a schematic diagram of the structure of the cleaning chamber provided by the present invention;

[0032] Figure 3 This is a partial schematic diagram of the elastic membrane layer provided by the present invention;

[0033] Figure 4 This is a schematic diagram of the drying chamber provided by the present invention. Detailed Implementation

[0034] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0035] The implementation of the present invention will be described in detail below with reference to specific embodiments.

[0036] In the accompanying drawings of this embodiment, the same or similar reference numerals correspond to the same or similar components. In the description of this invention, it should be understood that if terms such as "upper," "lower," "left," and "right" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, they are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, the terms used to describe positional relationships in the accompanying drawings are only for illustrative purposes and should not be construed as limiting this patent. For those skilled in the art, the specific meaning of the above terms can be understood according to the specific circumstances.

[0037] Reference Figure 1-4 The image shows a preferred embodiment of the present invention.

[0038] The present invention provides a method for preparing an environmentally friendly cementing material suitable for coal briquettes, comprising the following preparation steps:

[0039] 1) The coal gangue is placed in a washing machine for washing to form clean material; the washing machine includes a machine body, which has a washing chamber. The top of the washing chamber is provided with a feed port, and the bottom of the washing chamber is provided with a discharge plate 120 that swings up and down. The discharge plate 120 covers the discharge port, and the bottom of the washing chamber is provided with a liquid outlet with a filter screen.

[0040] The cleaning fluid enters the cleaning chamber through the inlet on the machine body. The cleaning fluid washes the coal gangue in the cleaning chamber and carries the impurities on the surface of the coal gangue out through the outlet. Then, the discharge plate 120 is swung to open the discharge port, and the clean material rolls downward through the discharge port.

[0041] 2) The clean material is crushed to form crushed material;

[0042] 3) The crushed material is screened by a screening machine and then dried to obtain fine gangue;

[0043] 4) Fine gangue, slag, gypsum, fly ash, clinker, and steel slag powder are loaded into a ball mill and ball-milled to form powder.

[0044] 5) Mix the powder evenly to form an environmentally friendly cementitious material.

[0045] The above-mentioned method for preparing environmentally friendly cementitious materials suitable for coal block cementing involves grinding and mixing fine-grained gangue with slag, gypsum, fly ash, clinker, and steel slag powder in a certain proportion to form a cementitious material for preparing environmentally friendly coal block cemented backfill. This method realizes the utilization of solid waste and improves the hydration reaction rate of slag in the hardening and strength growth process of the prepared coal block cemented backfill by grinding slag.

[0046] The preparation of environmentally friendly coal block cemented backfill is based on the material basis of the divalent metal oxides (CaO+MgO+FeO) in steel slag powder activating the formation of CSH gel in slag and aggregate. With the participation of gypsum, Al2O3 and Fe2O3 in slag and tailings are extracted to form iron-containing ettringite-like complex salts. The ettringite complex salts form needle-like crystals with nanometer diameter, thus enhancing and toughening the hardened body. Utilizing the activating effect of steel slag powder, desulfurized gypsum powder, and blast furnace water-quenched slag powder, a large number of needle-like complex salt crystals are formed, along with a large amount of near-amorphous CSH gel, which tightly encapsulates the needle-like complex salt crystals, significantly improving the stability of the entire system.

[0047] Based on the design principles of cement-based materials, the following mix proportion range is proposed:

[0048]

[0049] Strength of environmentally friendly cementitious materials:

[0050]

[0051]

[0052] In addition, this environmentally friendly cementitious material also possesses other excellent properties, all of which are superior to ordinary Portland cement:

[0053] The cementitious material has a fine particle size, meeting the requirements for early strength, and requires less water. This is because the material composition contains a certain amount of high-quality fly ash. The initial setting time of the cementitious material is later than 1 hour, and the final setting time is about 6 hours. This ensures that the working performance of the support cementitious material is not affected, while also ensuring that hydration is completed in a short time, achieving the early hardening effect of the material.

[0054] This environmentally friendly cementitious material is designed based on tailings waste rock concrete. To address low-quality aggregates with low mud content and high crushing values, it is necessary to accelerate the hydration reaction on the aggregate surface, increase hydration products with high strength properties, and form a network structure to effectively encapsulate the aggregates. Ultimately, this material can be used for high-strength precast components, artificial reefs, etc.

[0055] Solid waste accounts for more than 60% of the material composition, making it an environmentally friendly material with green and low-carbon properties.

[0056] The slag is blast furnace water-quenched slag.

[0057] The total content of divalent metal oxides (CaO+MgO+FeO) in typical steel slag reaches 70% to 80%.

[0058] The middle part of the cleaning chamber is provided with a vibrating rod 110 that reciprocates up and down. The bottom of the vibrating rod 110 extends downward to the lower part of the cleaning chamber to form a bottom section. Multiple radially outwardly expanding vibrating disks 111 are formed on the outer periphery of the bottom section. The multiple vibrating disks 111 are arranged vertically at intervals along the height direction of the bottom section. There is an annular gap between the outer periphery of the vibrating disk 111 and the side wall of the cleaning chamber. The top of the vibrating disk 111 forms a vibration surface.

[0059] In step 1), during the washing of the coal gangue with the cleaning fluid, the vibrating rod 110 vibrates up and down, causing the coal gangue on the vibrating surface to vibrate up and down. Adjacent coal gangue rubs against each other, promoting the removal of impurities from the surface of the coal gangue. This removes impurities from the surface of the coal gangue, preventing it from affecting the performance of the cementitious material. Thus, the up-and-down vibration of the coal gangue on the vibrating surface by the vibrating plate 111 causes impurities to fall off, and the friction between adjacent coal gangue removes surface dirt and dust. The washing fluid also cleans organic matter and oil stains from the surface of the coal gangue.

[0060] The cleaning solution includes organic solvents.

[0061] Along the radial direction of the vibratory plate 111 from the inside out, the vibrating surface is inclined downwards.

[0062] In step 1), when the discharge port is open, the clean material on the vibrating surface rolls downwards along the inclined direction of the vibrating surface. In this way, the design of the vibrating surface guides the clean material out of the discharge.

[0063] The cleaning chamber has a circumferential inner wall, on which multiple external water spray heads 130 are provided. The multiple external water spray heads 130 are arranged at intervals along the circumference of the inner wall to form an external water spray ring. The multiple external water spray rings are arranged at intervals along the height direction of the inner wall.

[0064] In step 1), the external water nozzle 130 sprays the cleaning fluid toward the center of the cleaning chamber. In this way, the vibrating coal gangue is flushed from the outside to the inside in multiple directions.

[0065] Multiple inner water spray holes 140 are formed on the outer periphery of the vibrating rod 110. The multiple inner water spray holes 140 are arranged at intervals along the circumference of the vibrating rod 110 to form an inner water spray ring. The multiple inner water spray rings are arranged at intervals along the height direction of the vibrating rod 110.

[0066] In step 1), the inner water spray hole 140 sprays the cleaning fluid toward the inner peripheral wall. In this way, the vibrating coal gangue is flushed from the inside out in multiple directions.

[0067] An elastic membrane layer 150 is provided on the outer side of the inner water spray hole 140, and the middle part of the elastic membrane layer 150 covers the inner water spray hole 140; the elastic membrane layer 150 and the outer periphery of the vibrating rod 110 surround to form an elastic region, and the elastic membrane layer 150 is provided with a plurality of membrane holes 151, which are staggered on the elastic membrane layer 150; the vibrating plate 111 is provided with a plurality of upwardly protruding elastic strips 160, the top of the elastic strips 160 forming an abutment end, and the plurality of elastic strips 160 are aligned with the plurality of elastic membrane layers 150 respectively;

[0068] In step 1), as the inner water spray hole 140 sprays cleaning fluid toward the elastic region, the elastic region expands and deforms outward, and the middle part of the elastic membrane layer 150 bulges outward to form a protrusion. The outer surface of the protrusion presses against the coal gangue on the vibrating disk 111, causing the membrane hole 151 to expand and deform outward. Multiple membrane holes 151 spray water in multiple directions toward the outer side of the elastic membrane layer 150. The elastic strip 160 deforms with the up-and-down vibration of the vibrating disk 111, and the contact end repeatedly presses against the protrusion, causing the cleaning fluid in the elastic region to spray outward through the membrane hole 151. In this way, the design of the elastic membrane layer 150 allows water to be sprayed from one water spray hole in multiple directions, and increases the impact force of the water flow. At the same time, the design of the elastic strip 160, under the action of inertia, causes the elastic strip 160 to bend and deform with vibration, like a snake repeatedly pressing on the surface of the elastic membrane layer 150, causing the water in the elastic region to be sprayed out through the membrane hole 151 at an accelerated speed.

[0069] In step 3), the crushed material is screened to form coarse material larger than the set particle size and fine material smaller than the set particle size. The fine material is then dried in a drying oven to form fine-grained gangue. In this way, the coarse-grained gangue can be used as aggregate in the preparation of environmentally friendly coal block cemented backfill, and the fine material is dried in a drying oven to avoid hydration of the cementitious material.

[0070] The drying oven includes a box body, a drying chamber 200 in the box body, a heat-conducting plate made of metal in the drying chamber 200, a plate cavity in the heat-conducting plate, and an air outlet in the drying chamber 200, which is arranged facing the plate cavity.

[0071] In step 3), the fine material is placed in the disc cavity, and hot air is directed through the air outlet to dry it until it is completely dry, forming fine-grained gangue. This unidirectional hot air drying process dehydrates and dries the material, preventing hydration of the cementitious material. The metal heat-conducting disc design ensures that the material in the disc cavity is kept in a high-temperature, environmentally friendly environment.

[0072] The bottom of the drying chamber 200 is provided with push plates 210 on both sides, which can move towards each other or away from each other. The push plates 210 are connected to moving rods that can move back and forth. The push plates 210 are arranged laterally in the drying chamber 200, and the bottom of the push plates 210 presses against the bottom of the drying chamber 200. The two push plates 210 have front push surfaces 211 arranged opposite to each other, and a plate gap is formed between the two front push surfaces 211. The front push surfaces 211 extend inward at an inward angle along the direction from bottom to top.

[0073] In step 3), during the drying process of the fine material, as the two push plates 210 move towards each other, the plate gap narrows, and the fine material at the bottom of the plate gap moves upward along the extension direction of the front push surface 211. Through the design of the push plates 210, the material located at the bottom can be pushed upward during the drying process.

[0074] Each of the two push plates 210 has a rear push surface 212 arranged opposite to each other. The rear push surface 212 extends inwardly along the direction from bottom to top, and a surface gap is formed between the rear push surface 212 and the side of the drying chamber 200.

[0075] In step 3), during the drying process of the fine material, when the two push plates 210 move away from each other, the surface gap shrinks, and the fine material on the bottom of the surface gap moves upward along the extension direction of the rear push surface 212.

[0076] Specifically, the sidewalls of the drying chamber 200 extend outwards at an angle from bottom to top. When material is pressed against the sidewalls of the drying chamber 200, it moves upwards along these sidewalls. This allows material at the bottom to be pushed upwards during the drying process.

[0077] In a preferred embodiment, a plurality of elastic arc plates 220 are arranged in the plate space. The plurality of elastic arc plates 220 are arranged in parallel and spaced apart in the plate space. The two ends of the elastic arc plates 220 are respectively fixed to the bottom of the front push surface 211. The middle part of the elastic arc plates 220 is arranged to arch upward to form an arched part.

[0078] When the two push plates 210 move towards each other, the plate gap decreases, and the elastic arc plate 220 bends and deforms under force, with the arched part deforming upwards, causing the crushed material at the bottom of the plate gap to move upwards. When the two push plates 210 move away from each other, the plate gap increases, the arched part bends downwards, and the material on both sides of the arched part moves downwards. In this way, by utilizing the action of the elastic arc plate 220, the material moves longitudinally and laterally, promoting uniform heating and facilitating the evaporation of water at the bottom.

[0079] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for preparing environmentally friendly cementing materials suitable for coal briquettes, characterized in that, The preparation steps include the following: 1) Coal gangue is placed in a washing machine for washing to form clean material; the washing machine includes a machine body, the machine body has a washing chamber, the top of the washing chamber is provided with a feed port, the bottom of the washing chamber is provided with a discharge plate that swings up and down, the discharge plate is covered on the discharge port, the bottom of the washing chamber is provided with a liquid outlet, and a filter screen is provided on the liquid outlet. The cleaning fluid enters the cleaning chamber through the inlet on the machine body. The cleaning fluid washes the coal gangue in the cleaning chamber and carries the impurities on the surface of the coal gangue out through the outlet. Then, the discharge plate is swung to open the discharge port, and the clean material rolls downward through the discharge port. 2) The cleaned material is crushed to form crushed material; 3) The crushed material is screened by a screening machine and then dried to obtain fine gangue; 4) According to the set ratio, the fine gangue, slag, gypsum, fly ash, clinker and steel slag powder are loaded into a ball mill and ball-milled to form powder. 5) Mix the powder evenly to form the environmentally friendly cementitious material; The cleaning chamber is provided with a vibrating rod that reciprocates up and down in the middle. The bottom of the vibrating rod extends downward to the lower part of the cleaning chamber to form a bottom section. Multiple radially outwardly expanding vibrating discs are formed on the outer periphery of the bottom section. The multiple vibrating discs are arranged at intervals up and down along the height direction of the bottom section. There is an annular gap between the outer periphery of the vibrating disc and the side wall of the cleaning chamber. The top of the vibrating disc forms a vibration surface. In step 1), during the process of washing the coal gangue with the cleaning fluid, the vibrating rod vibrates up and down, the coal gangue on the vibrating surface vibrates up and down, and adjacent coal gangue rub against each other, causing impurities on the surface of the coal gangue to fall off. The vibrating surface extends downwards at an angle along the radial direction of the vibratory plate from the inside out. In step 1), when the discharge port is open, the clean material on the vibrating surface rolls downward along the inclined direction of the vibrating surface; The cleaning chamber has a circumferential inner wall, on which a plurality of external water spray heads are provided. The plurality of external water spray heads are arranged at intervals along the circumference of the inner wall to form an external water spray ring. The plurality of external water spray rings are arranged at intervals along the height direction of the inner wall. In step 1), the external water spray head sprays the cleaning fluid toward the center of the cleaning chamber; Multiple inner water spray holes are formed on the outer periphery of the vibrating rod. The multiple inner water spray holes are arranged at intervals along the circumference of the vibrating rod to form an inner water spray ring. The multiple inner water spray rings are arranged at intervals along the height direction of the vibrating rod. In step 1), the inner water spray hole sprays the cleaning fluid toward the inner peripheral wall.

2. The method for preparing environmentally friendly cementing material suitable for coal lumps as described in claim 1, characterized in that, In step 3), the crushed material is screened to form coarse material larger than the set particle size and fine material smaller than the set particle size. The fine material is dried in a drying oven to form fine gangue. The set particle size is 10 mm.

3. The method for preparing environmentally friendly cementing material suitable for coal lumps as described in claim 2, characterized in that, The drying oven includes a box body, a drying chamber in the box body, a heat-conducting plate made of metal in the drying chamber, a plate cavity in the heat-conducting plate, and an air outlet in the drying chamber, the air outlet being arranged towards the plate cavity; In step 3), the fine material is placed in the disc cavity, and the air outlet dries the fine material with hot air until the fine material is completely dry, forming fine gangue.

4. The method for preparing environmentally friendly cementing material suitable for coal lumps as described in claim 3, characterized in that, The bottom of the drying chamber is provided with push plates on both sides, which can move towards each other or away from each other. The push plates are connected to moving rods that can move back and forth. The push plates are arranged horizontally in the drying chamber, and the bottom of the push plates presses against the bottom of the drying chamber. The two push plates have front pushing surfaces arranged opposite each other, and a plate gap is formed between the two front pushing surfaces. The front pushing surfaces are arranged to extend inward at an inward angle along the direction from bottom to top. In step 3), during the drying process of the fine material, when the two push plates move towards each other, the plate gap narrows, and the fine material at the bottom of the plate gap moves upward along the extension direction of the front push surface.

5. The method for preparing environmentally friendly cementing material suitable for coal lumps as described in claim 4, characterized in that, The two push plates each have a rear push surface arranged opposite to each other. The rear push surface extends inward at an inward angle along the direction from bottom to top, and a surface gap is formed between the rear push surface and the side of the drying chamber. In step 3), during the drying process of the fine material, when the two push plates move away from each other, the surface gap decreases, and the fine material on the bottom of the surface gap moves upward along the extension direction of the rear push surface.

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