A method for disposing coal gangue in a layered landfill

Abstract

The present application relates to coal gangue disposal technical field, specifically to a kind of coal gangue layered landfill disposal method, comprising the following steps: S1, landfill site pretreatment;S2, pipeline pre-buried processing: first pre-buried pipe and second pre-buried pipe are arranged on the landfill site, one end of first pre-buried pipe is located on pre-buried site, the other end extends to pre-buried site outside, second pre-buried pipe is vertically arranged on pre-buried site and is communicated with first pre-buried pipe, and a plurality of air holes are arranged on second pre-buried pipe along the length direction;S3, layered landfill processing: coal gangue layer and loess layer are filled on the landfill site, and layered structure of coal gangue layer-loess layer-coal gangue layer is formed, the uppermost layer of layered structure is loess layer, and coal gangue layer and loess layer are both compacted;Second pre-buried pipe is provided with air hole in corresponding position of each layer of coal gangue layer;S4, anti-oxygen gas is transported into second pre-buried pipe through first pre-buried pipe.The present application can reduce the risk of spontaneous combustion of coal gangue layer.

Description

Technical Field

[0001] This invention relates to the field of coal gangue disposal technology, specifically to a method for the layered landfill disposal of coal gangue. Background Technology

[0002] Coal gangue is a waste product generated during coal mining, accounting for approximately 10% of coal production. The coal gangue discharged during mining and washing processes accumulates into gangue mountains, posing a significant environmental hazard: it encroaches on land, impacts the ecosystem, and damages the landscape; the leachate (acidic water) from these gangue mountains pollutes groundwater and rivers, endangering crops and aquaculture; due to the presence of iron sulfide and carbonaceous substances in coal gangue, it can spontaneously combust, emitting large amounts of smoke and dust, severely polluting the atmosphere, harming human health, inhibiting plant growth, and corroding building structures; some coal gangue mountains also pose an explosion hazard, seriously threatening the safety of mining areas.

[0003] The most common way to dispose of coal gangue is to compact it in layers, cover each layer of coal gangue with a layer of loess, compact each layer of loess, and finally cover the surface of the coal gangue with another layer of loess and compact it.

[0004] Regarding the aforementioned technologies, the applicant believes that although the surface of the coal gangue pile has been compacted, the coal gangue has many pores, allowing outside air to easily enter and cause oxidation inside, which in turn leads to spontaneous combustion. Summary of the Invention

[0005] The purpose of this invention is to provide a method for the layered landfill disposal of coal gangue, so as to suppress the oxidation rate inside the coal gangue and reduce the risk of spontaneous combustion of the coal gangue.

[0006] This invention is achieved through the following technical solution:

[0007] A method for the layered landfill disposal of coal gangue includes the following steps:

[0008] S1. Landfill site pretreatment;

[0009] S2, S2, Pipeline pre-embedding treatment: A first pre-embedding pipe and a second pre-embedding pipe are installed on the landfill site. One end of the first pre-embedding pipe is located on the landfill site and the other end extends to the outside of the landfill site. One end of the second pre-embedding pipe is located on the landfill site and is connected to the first pre-embedding pipe, and the other end extends upward. Multiple ventilation holes are opened along the length direction of the second pre-embedding pipe. The top of the second pre-embedding pipe is sealed.

[0010] S3. Layered landfill treatment: A layer of coal gangue is laid at the landfill site, then a layer of loess is laid on the coal gangue layer, and then another layer of coal gangue is laid on the loess layer. The above laying steps are repeated to form a layered structure of coal gangue layer-loess layer-coal gangue layer. The top layer of the layered structure is the loess layer, and both the coal gangue layer and the loess layer are compacted. The second pre-buried pipe is provided with ventilation holes at the corresponding parts of each coal gangue layer.

[0011] S4. Antioxidant gas is delivered into the second pre-embedded pipe through the first pre-embedded pipe.

[0012] Furthermore, in step S1, the landfill site is first leveled and compacted, then a waterproof membrane is laid on the landfill site, and then a hardening layer is set on top of the waterproof membrane.

[0013] Furthermore, in step S1, a concrete retaining wall is set up around the landfill site, and the layered structure is located inside the concrete retaining wall.

[0014] Furthermore, in step S2, a third pre-buried pipe is also installed on the landfill site. One end of the third pre-buried pipe is connected to the landfill site, and the other end extends to the top loess layer. Multiple ventilation holes are opened along the length of the third pre-buried pipe. Ventilation holes are provided at the corresponding parts of the third pre-buried pipe and each coal gangue layer. An oxygen measuring component is installed on the third pre-buried pipe. The oxygen measuring component includes a cap and an oxygen sensor. The cap is detachably installed at the top opening of the third pre-buried pipe. The oxygen sensor is installed inside the third pre-buried pipe and is electrically connected to a controller.

[0015] Furthermore, the cap is connected to the third pre-embedded pipe by threads. A vertical rod is provided on one side of the cap inside the third pre-embedded pipe. The vertical rod extends towards the pre-embedded site, and multiple sealing rings are provided on the vertical rod along its length. All of the sealing rings are in sliding seal with the inner wall of the third pre-embedded pipe. An oxygen sensor is provided between two adjacent sealing rings, and an oxygen sensor is provided at a corresponding location inside each layer of coal gangue.

[0016] Furthermore, a gas storage device is connected to one end of the first pre-buried pipe located outside the landfill site. The gas storage device stores antioxidant gas and is used to deliver the antioxidant gas to the first pre-buried pipe.

[0017] Furthermore, the gas storage device includes a first gas storage tank and a second gas storage tank. A first gas supply pipe is connected between the first gas storage tank and the first pre-embedded pipe, and a second gas supply pipe is connected between the second gas storage tank and the first pre-embedded pipe. A first solenoid valve is installed on the first gas supply pipe, and a second solenoid valve is installed on the second gas supply pipe. The first solenoid valve is electrically connected to a controller. The first gas storage tank stores nitrogen, and the second gas storage tank stores helium.

[0018] Further, in step S4, the first solenoid valve and the second solenoid valve are opened, and nitrogen and helium are delivered into the second pre-embedded pipe through the first pre-embedded pipe. The helium concentration at each part of the outside of the layered structure is detected, and the parts of the outside of the layered structure with a helium concentration higher than that in normal air are further compacted and solidified.

[0019] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0020] 1. Antioxidant gas is delivered from the first pre-embedded pipe to the second pre-embedded pipe. The antioxidant gas flows into the pores inside each coal gangue layer through the vent holes on the second pre-embedded pipe. The antioxidant gas can squeeze out the oxygen inside the coal gangue layer, reduce the oxygen content inside the coal gangue layer, and help inhibit the oxidation reaction inside the coal gangue layer, thereby reducing the possibility of spontaneous combustion inside the coal gangue layer. Attached Figure Description

[0021] The accompanying drawings, which are included to provide a further understanding of the embodiments of the present invention and form part of this application, are not intended to limit the embodiments of the present invention.

[0022] In the attached diagram:

[0023] Figure 1 This is a schematic diagram of the layered landfill structure for coal gangue according to Embodiment 1 of the present invention.

[0024] The attached diagram shows the markings and corresponding component names:

[0025] 1. First embedded pipe; 2. Second embedded pipe; 3. Vent hole; 4. Coal gangue layer; 5. Loess layer; 6. Hardened layer; 7. Concrete retaining wall; 8. Third embedded pipe; 9. Vent hole; 10. Cover; 11. Oxygen sensor; 12. Vertical rod; 13. Mounting plate; 14. Sealing ring; 15. First gas storage tank; 16. Second gas storage tank; 17. First gas transmission pipe; 18. Second gas transmission pipe; 19. First solenoid valve; 20. Second solenoid valve. Detailed Implementation

[0026] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to embodiments and accompanying drawings. The illustrative embodiments and descriptions of this invention are for illustrative purposes only and are not intended to limit the invention. It should be noted that this invention is already in the actual research and development stage.

[0027] Example 1

[0028] A method for layered landfill disposal of coal gangue, referring to Figure 1 This includes the following steps:

[0029] S1. Landfill site pretreatment;

[0030] S2. Pipeline pre-embedding treatment: A first pre-embedding pipe 1 and a second pre-embedding pipe 2 are installed on the landfill site. One end of the first pre-embedding pipe 1 extends to the middle of the pre-embedding site and the other end extends to the outside of the pre-embedding site. One end of the second pre-embedding pipe 2 is located in the middle of the pre-embedding site and is connected to the first pre-embedding pipe 1. The other end extends upward. Multiple ventilation holes 3 are opened on the second pre-embedding pipe 2 along the length direction, and the top end of the second pre-embedding pipe 2 is sealed.

[0031] S3. Layered landfill treatment: A layer of coal gangue 4 is laid in the landfill site, then a layer of loess 5 is laid on the coal gangue layer 4, and then another layer of coal gangue 4 is laid on the loess layer 5. The above laying steps are repeated to form a layered structure of coal gangue layer 4-loess layer 5-coal gangue layer 4. The top layer of the layered structure is the loess layer 5, and both the coal gangue layer 4 and the loess layer 5 are compacted. The top of the second pre-buried pipe 2 extends above the top loess layer 5. The second pre-buried pipe 2 is provided with ventilation holes 3 at the corresponding parts of each coal gangue layer 4. The second pre-buried pipe 2 is buried by the layered structure.

[0032] S4. Antioxidant gas is delivered into the second pre-embedded pipe 2 through the first pre-embedded pipe 1.

[0033] In this scheme, antioxidant gas is delivered from the first pre-embedded pipe 1 to the second pre-embedded pipe 2. The antioxidant gas flows into the pores inside each coal gangue layer 4 through multiple vent holes 3 on the second pre-embedded pipe 2. The antioxidant gas can squeeze out the oxygen inside the coal gangue layer 4, reduce the oxygen content inside the coal gangue layer 4, which helps to inhibit the oxidation reaction inside the coal gangue layer 4, thereby reducing the possibility of spontaneous combustion inside the coal gangue layer 4.

[0034] As a preferred implementation method, refer to Figure 1 In step S1, the landfill site is first leveled and compacted, then a waterproof membrane is laid on the landfill site, and then a hardening layer 6 is set on top of the waterproof membrane. The hardening layer 6 can be a cement layer to enhance the load-bearing capacity and seepage prevention performance of the landfill site, and reduce the seepage of polluted water formed after rainwater comes into contact with the coal gangue layer 4 into the ground to pollute groundwater and rivers.

[0035] As a preferred implementation method, refer to Figure 1 In step S1, a concrete retaining wall 7 is set up around the landfill site. The layered structure is located inside the concrete retaining wall 7, which can reduce the possibility of landslides and collapses of the layered structure. If the layered structure does landslide and collapse, it will easily accelerate the air circulation between the outside air and the layered structure, thereby accelerating the oxidation of the coal gangue layer 4. The concrete retaining wall 7 can help stabilize the layered structure.

[0036] As a preferred implementation method, refer to Figure 1 In step S2, a third pre-buried pipe 8 is also installed on the landfill site. One end of the third pre-buried pipe 8 abuts against the landfill site, and the other end extends above the uppermost loess layer 5. Multiple ventilation holes 9 are opened along the length of the third pre-buried pipe 8. Ventilation holes 9 are provided at corresponding locations on each layer of coal gangue 4. An oxygen measuring component is installed on the third pre-buried pipe 8. The oxygen measuring component includes a cap 10 and an oxygen sensor 11. The cap 10 is detachably installed at the top opening of the third pre-buried pipe 8. The oxygen sensor 11 is installed inside the third pre-embedded pipe 8 and is electrically connected to the controller. The oxygen concentration inside the third pre-embedded pipe 8 can be monitored through the oxygen measuring component. When the oxygen concentration inside the third pre-embedded pipe 8 is high, it indicates that the oxygen concentration inside the coal gangue layer 4 is high and there is good ventilation between the coal gangue layer 4 and the outside. At this time, the controller issues an alarm message and then oxygen-resistant gas can be delivered to the second pre-embedded pipe 2 through the first pre-embedded pipe 1 to control the oxygen content inside the coal gangue layer 4.

[0037] As a preferred implementation method, refer to Figure 1 The cover 10 is bolted to the third pre-embedded pipe 8. A vertical rod 12 is installed on one side of the cover 10 inside the third pre-embedded pipe 8. The vertical rod 12 extends towards the pre-embedded site. An mounting plate 13 is installed on the vertical rod 12. An oxygen sensor 11 is located on the mounting plate 13. Multiple sealing rings 14 are installed along the length of the vertical rod 12. All sealing rings 14 are slidably sealed to the inner wall of the third pre-embedded pipe 8. An oxygen sensor 11 is installed between two adjacent sealing rings 14. An oxygen sensor 11 is also installed at the corresponding part inside each layer of coal gangue 4. The oxygen content inside each layer of coal gangue 4 is monitored by multiple oxygen sensors 11, which makes it easier to intuitively detect that the oxygen content inside a specific layer of coal gangue 4 is too high, and thus focus on and treat the corresponding coal gangue layer 4.

[0038] As a preferred implementation method, refer to Figure 1The first pre-buried pipe 1 is connected to a gas storage device at one end outside the landfill site. The gas storage device stores oxygen gas and is used to deliver oxygen gas to the first pre-buried pipe 1. When the oxygen sensor 11 detects that the oxygen content inside a certain coal gangue layer 4 is too high, the gas storage device can conveniently and promptly deliver oxygen gas to the second pre-buried pipe 2 through the first pre-buried pipe 1, and then deliver oxygen gas into the coal gangue layer 4, which facilitates the control of the oxygen content inside the coal gangue layer 4. In addition, when the oxygen gas flows inside the coal gangue layer 4, it can carry away the heat generated by the oxidation reaction inside the coal gangue layer 4 due to the presence of a small amount of oxygen. The heat inside the coal gangue layer 4 is finally carried out of the layered structure with the oxygen gas, which destroys the oxygen supply and heat storage conditions of the coal gangue layer 4 and can prevent spontaneous combustion of the coal gangue layer 4 to a certain extent.

[0039] As a preferred implementation method, refer to Figure 1 The gas storage device includes a first gas storage tank 15 and a second gas storage tank 16. A first gas supply pipe 17 is connected between the first gas storage tank 15 and the first pre-embedded pipe 1, and a second gas supply pipe 18 is connected between the second gas storage tank 16 and the first pre-embedded pipe 1. A first solenoid valve 19 is installed on the first gas supply pipe 17, and a second solenoid valve 20 is installed on the second gas supply pipe 18. The first solenoid valve 19 is electrically connected to the controller. The first gas storage tank 15 stores nitrogen, and the second gas storage tank 16 stores helium. When the oxygen sensor 11 detects that the oxygen content inside the coal gangue layer 4 is high, the controller opens the first solenoid valve 19, and the first gas storage tank 15 supplies nitrogen to the first pre-embedded pipe 1 through the first gas supply pipe 17, thereby supplying nitrogen to all the coal gangue layers 4 to control the oxygen content in the layered structure.

[0040] As a preferred implementation method, refer to Figure 1 In step S4, the first solenoid valve 19 and the second solenoid valve 20 are opened, and nitrogen and helium are supplied to the second pre-embedded pipe 2 through the first pre-embedded pipe 1. The helium concentration at various parts of the outer layer structure is detected. For parts of the outer layer structure where the helium concentration is higher than that in normal air, further compaction and solidification are carried out. Since helium has strong diffusivity, helium flows quickly from the second pre-embedded pipe 2 through the coal gangue layer 4 and diffuses to the outer layer structure. By detecting the helium content outside the layer structure, parts where the flow between the layer structure and the outside air is relatively smooth can be found. At this time, loess can be spread on the corresponding parts, and the loess and the layer structure can be further compacted. Grouting can also be carried out on the corresponding parts to isolate the communication channel between the coal gangue layer 4 and the outside air.

[0041] It should be noted that flowers, grasses and trees can be planted on the loess surface of the layered structure to stabilize the loess layer 5, reduce soil erosion on the surface of the loess layer 5, and reduce the exposure of the coal gangue layer 4 to the air.

[0042] Example 2

[0043] The difference between this embodiment and embodiment 1 is that, in this embodiment, the antioxidant gas stored in the first gas storage tank 15 can be neon, argon, krypton or xenon.

[0044] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for the layered landfill disposal of coal gangue, characterized in that: Includes the following steps: S1. Landfill site pretreatment; S2, Pipeline pre-embedding treatment: A first pre-embedding pipe (1) and a second pre-embedding pipe (2) are set on the landfill site. One end of the first pre-embedding pipe (1) is located on the landfill site and the other end extends to the outside of the landfill site. One end of the second pre-embedding pipe (2) is located on the landfill site and is connected to the first pre-embedding pipe (1), and the other end extends upward. Multiple ventilation holes (3) are opened on the second pre-embedding pipe (2) along the length direction. The top of the second pre-embedding pipe (2) is sealed. S3, Layered landfill treatment: A layer of coal gangue (4) is laid in the landfill site, and then a layer of loess (5) is laid on the coal gangue layer (4). The coal gangue layer (4) is laid on the loess layer (5) again. The laying steps are repeated to form a layered structure of coal gangue layer (4)-loess layer (5)-coal gangue layer (4). The uppermost layer of the layered structure is the loess layer (5). Both the coal gangue layer (4) and the loess layer (5) are compacted. The second pre-buried pipe (2) is provided with ventilation holes (3) at the corresponding parts of each coal gangue layer (4). S4. Antioxidant gas is delivered into the second pre-embedded pipe (2) through the first pre-embedded pipe (1). The antioxidant gas can squeeze out the oxygen inside the coal gangue layer, reduce the oxygen content inside the coal gangue layer, and help suppress the oxidation reaction inside the coal gangue layer, thereby reducing the spontaneous combustion inside the coal gangue layer. In step S2, a third pre-buried pipe (8) is also set on the landfill site. One end of the third pre-buried pipe (8) is connected to the landfill site, and the other end extends to the top loess layer (5). Multiple ventilation holes (9) are opened along the length direction of the third pre-buried pipe (8). Ventilation holes (9) are provided at the corresponding parts of the third pre-buried pipe (8) and each coal gangue layer (4). An oxygen measuring component is set on the third pre-buried pipe (8). The oxygen measuring component includes a cover (10) and an oxygen sensor (11). The cover (10) is detachably set at the top opening end of the third pre-buried pipe (8). The oxygen sensor (11) is set inside the third pre-buried pipe (8). The oxygen sensor (11) is electrically connected to a controller. The cap (10) is connected to the third pre-embedded pipe (8) by a thread. The cap (10) is provided with a vertical rod (12) on one side inside the third pre-embedded pipe (8). The vertical rod (12) extends towards the pre-embedded site. Multiple sealing rings (14) are provided on the vertical rod (12) along the length direction of the vertical rod (12). The multiple sealing rings (14) are all in sliding seal with the inner wall of the third pre-embedded pipe (8). An oxygen sensor (11) is provided between two adjacent sealing rings (14). The oxygen sensor (11) is provided at the corresponding part inside each layer of coal gangue (4). The first pre-buried pipe (1) is connected to a gas storage device at one end outside the landfill site. The gas storage device stores antioxidant gas and is used to deliver antioxidant gas to the first pre-buried pipe (1). The gas storage device includes a first gas storage tank (15) and a second gas storage tank (16). A first gas supply pipe (17) is connected between the first gas storage tank (15) and the first pre-embedded pipe (1). A second gas supply pipe (18) is connected between the second gas storage tank (16) and the first pre-embedded pipe (1). A first solenoid valve (19) is installed on the first gas supply pipe (17). A second solenoid valve (20) is installed on the second gas supply pipe (18). The first solenoid valve (19) is electrically connected to the controller. The first gas storage tank (15) stores nitrogen gas, and the second gas storage tank (16) stores helium gas. In step S4, the first solenoid valve (19) and the second solenoid valve (20) are opened, and nitrogen and helium are delivered into the second pre-embedded pipe (2) through the first pre-embedded pipe (1). The helium concentration of each part outside the layered structure is detected, and the parts outside the layered structure with helium concentration higher than that in normal air are further compacted and solidified.

2. The method for layered landfill disposal of coal gangue according to claim 1, characterized in that: In step S1, the landfill site is first leveled and compacted, then a waterproof membrane is laid on the landfill site, and then a hardening layer is set on top of the waterproof membrane (6).

3. The method for layered landfill disposal of coal gangue according to claim 1, characterized in that: In step S1, a concrete retaining wall (7) is set up around the landfill site, and the layered structure is located inside the concrete retaining wall (7).

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