Coal-based solid waste and CO2 collaborative filling and sealing process

Abstract

The invention discloses a coal-based solid waste and CO2 collaborative filling and sealing process which comprises the following steps: firstly, designing and arranging a short-wall continuous mining and continuous filling working face, and dividing the working face into n strips along a direction parallel to an open-off cut; then stoping is carried out every m strips from the first strip, the strips are closed after stoping, and paste filling materials are used for filling; m strips left between every two pasty fluid filling materials are sequentially stoped, the m strips are closed after stoping, and a plurality of closed unit spaces are formed; performing jet grouting plugging on cracks and separation layer spaces in overlying strata of the unit spaces; and finally, filling the reaction type slurry filling material into the constructed unit space, and injecting the supercritical CO2 into the unit space to realize the storage of CO2. According to the technology, the coal-based solid waste can be treated, CO2 can be sealed and stored, meanwhile, the underground space after coal mining is effectively utilized, and the effect of achieving three purposes through one stroke is achieved.

Description

Technical Field

[0001] The present invention belongs to the technical field of coal-based solid waste filling and carbon capture and carbon storage, and relates to a method for 2 Collaborative filling and sealing process. Background Art

[0002] In the whole life cycle of coal mining, transportation, processing, utilization and waste treatment, a large amount of coal-based solid waste and CO are emitted at each stage. 2 And other greenhouse gases.

[0003] Therefore, the present invention provides a method for treating coal-based solid waste and CO 2 The collaborative filling and sealing process can not only dispose of coal-based solid waste in a green and efficient manner, but also achieve CO 2 underground storage. Summary of the invention

[0004] The purpose of the present invention is to provide a coal-based solid waste and CO 2 The collaborative filling and sealing process solves the problem of large-scale ground stacking of coal-based solid waste and CO 2 The problem of pollution caused by discharge.

[0005] The technical solution adopted by the present invention is: Coal-based solid waste and CO 2 The collaborative filling and sealing process first designs and arranges a short-wall continuous mining and filling working face, and divides the working face into two parts parallel to the cutting direction. n strips; then starting from the first strip, each m The strips are mined, and the strips are closed after mining, and the paste filling materials are used to fill the strip tunnels after mining; the strips left between each two paste filling materials are mined in turn. m After mining, the strip is closed. m strips to form several closed unit spaces; use strong adhesive slurry filling materials to inject grout to seal the cracks and delamination spaces in the overlying rock strata of the unit space; finally, fill the reactive slurry filling materials into the constructed unit space, and then supercritical CO 2 Injected into the unit space, it reacts with the reactive slurry filling material to produce a mineralized reaction, achieving CO 2 of storage.

[0006] The present invention is also characterized in that: Coal-based solid waste and CO 2 The collaborative filling and sealing process is implemented in the following steps: Step 1, preparing a paste filling material, a strong adhesive slurry filling material and a reactive slurry filling material; Step 2: Design and arrange the short-wall continuous mining and filling working face, and excavate the cutting eye, working face transportation chute, working face return air chute, return air main lane and transportation main lane to form a transportation and ventilation system; Step 3: Divide the short-wall continuous mining and filling working surface into n strips; Step 4: Start from the strip adjacent to the cut eye, m After the strips are mined, the two ends of the strips are sealed with a mobile isolation device, and the paste filling material is filled into the strip tunnel after mining; Step 5: After the paste filling material filled in step 4 solidifies, the remaining paste filling material between each two paste filling materials is collected in turn. m strips, and then use mobile isolation devices to separate the mined m The two ends of each strip are closed to form a number of closed unit spaces; Step 6: Use a strong adhesive slurry filling material to inject grout to seal the cracks and delamination spaces in the overlying rock strata of the unit space; Step 7, drilling a hole on the mobile isolation device, and filling the reactive slurry filling material into the constructed unit space through a pipeline. After filling, the drilled hole on the mobile isolation device is closed; Step 8: Supercritical CO 2 By CO 2 The delivery pipe is injected into the unit space to react with the reactive slurry filling material to achieve CO 2 of storage.

[0007] The paste filling material is prepared from the following raw material components according to mass percentage: 58% coal gangue, 10% cement, 10% fly ash, 2% additives and 20% water; the strong adhesive slurry filling material is prepared from the following raw material components according to mass percentage: 68% coal gangue, 2% additives and 30% water; the reactive slurry filling material is prepared from the following raw material components according to mass percentage: 48% alkaline coal-based solid waste, 2% additives and 50% water.

[0008] The dip length of the short-wall continuous mining and filling working face is 80 to 120 m, and the strike length is 100 to 2000 m.

[0009] The width of the strip is 3~6m.

[0010] Strip mining equipment includes continuous mining machine, multi-purpose excavator or anchor mining unit.

[0011] During the strip mining process, the surrounding rock of the tunnel formed behind must be supported.

[0012] The outer diameter of the conveying pipeline for filling materials is 100~400mm, and the hole diameter of grouting borehole and filling borehole is 100~500mm.

[0013] In step 8, CO 2 The diameter of the delivery pipe is 200~700mm.

[0014] The beneficial effects of the present invention are: (1) Coal-based solid waste and CO 2 The collaborative filling and sealing process can not only realize the disposal of coal-based solid waste, but also realize CO 2 It not only seals up the coal, but also effectively utilizes the underground space after coal seam mining, achieving the effect of "killing three birds with one stone"; (2) The method of the present invention combines coal-based solid waste and CO 2 Combined with the treatment of coal-based solid waste and CO 2 The collaborative filling and sealing process solves the pollution problem caused by the ground stacking of a large amount of coal-based solid waste, as well as the CO 2 The problem of emissions causing global warming and threatening the ecosystem. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a plan view schematic diagram of the arrangement and division of the working surface in Example 1 of the present invention; Figure 2 It is a plan view schematic diagram of the first strip mining and paste filling in Example 1 of the present invention; Figure 3 It is a plan view schematic diagram of constructing a closed unit space in Example 1 of the present invention; Figure 4 The filling material and CO in Example 1 of the present invention 2 Schematic diagram of the mineralization reaction in a closed unit space; Figure 5 The filling material in Example 1 of the present invention blocks the crack separation space and the filling material and CO 2 Schematic cross-sectional view of the mineralization reaction in a closed cell space.

[0016] In the figure, 1. Strip, 2. Cutting eye, 3. Transport chute, 4. Return air chute, 5. Return air tunnel, 6. Transport tunnel, 7. Mobile isolation device, 8. Paste filling material, 9. Unit space, 10. Reactive slurry filling material, 11. Strong adhesive slurry filling material, 12. CO 2 Conveyor pipes, 13. Cracks and abscission spaces. DETAILED DESCRIPTION

[0017] The present invention is described in detail below with reference to the accompanying drawings and specific embodiments.

[0018] The present invention relates to coal-based solid waste and CO 2 The collaborative filling and sealing process is implemented in the following steps: Step 1, prepare three functional coal-based filling materials, the first one is a paste filling material, the second one is a strong adhesive slurry filling material, and the third one is a reactive slurry filling material.

[0019] The preparation sites of the three functional coal-based filling materials can be on the ground or underground. Among them, the paste filling material is prepared by the following raw material components according to mass percentage: 58% coal gangue, 10% cement, 10% fly ash, 2% additives and 20% water, and the strength can reach more than 5MPa; the strong bonding slurry filling material is prepared by the following raw material components according to mass percentage: 68% coal gangue, 2% additives and 30% water, which has certain bonding properties and can seal the cracks between rock masses; the reactive slurry filling material is prepared by the following raw material components according to mass percentage: 48% alkaline coal-based solid waste, 2% additives and 50% water, among which the alkaline coal-based solid waste includes coal gangue, fly ash, gasification ash, desulfurization gypsum, etc., which can react with CO 2 Double decomposition reaction occurs to generate carbonate, realizing CO 2 Mineralization storage.

[0020] Step 2, such as Figure 1 As shown in the figure, a short-wall continuous mining and filling working face is designed and arranged, and its inclined length x 80~120m, strike length y The length of the tunnel is 100 to 2000m, and the cutting eye 2, the working face transport drift 3, the working face return air drift 4, the return air tunnel 5 and the transport tunnel 6 are excavated to form a transport and ventilation system.

[0021] Step 3: Divide the short-wall continuous mining and filling working face into n Stripe 1, stripe width a Determined according to the geological conditions of the coal seam, that is n = y / a ,width a Generally, it is 3~6m, and the strips are numbered in sequence from the opening eye to the stop line, numbered as ①, ②, ③... .

[0022] Step 4, such as Figure 2 As shown, starting from strip ①, each interval m Each strip is mined from the transport chute 3 to the return air chute 4. After each strip is mined, a mobile isolation device 7 is used to seal the two ends of the mined strip, and a pipeline is used to fill the prepared paste filling material 8 into the strip tunnel after mining.

[0023] Step 5, such as Figure 3 As shown, after the paste filling material 8 filled in step 4 solidifies to a strength that meets the requirements, the same mining process as in step 4 is used to sequentially mine the remaining space between each two paste filling materials 8. m strips, 7 pairs of mobile isolation devices are used after mining m The two ends of the strip width are closed to form a plurality of closed unit spaces 9.

[0024] In step 4 and step 5, the strip mining equipment can be excavation equipment such as continuous miners, fully mechanized excavators, anchor and digging units, and the specific equipment depends on the actual situation of the application mine; in addition, during strip mining, it is necessary to support the surrounding rock of the tunnel formed at the rear.

[0025] The length of the unit space 9 formed in step 5 is ma , width is x The surrounding area is composed of paste filling material 8 and mobile isolation device 7. The bottom is the coal seam floor and the top is the coal seam roof. There is a thick and hard geological cover in the overlying rock layer on the roof to prevent CO 2 It then dissipates after entering unit space 9.

[0026] Step 6, such as Figure 5 As shown, a strong adhesive slurry filling material 11 is used to inject grout to seal the cracks and delamination spaces 13 in the overlying rock strata above the unit space 9, thereby improving the overlying rock strength and airtightness.

[0027] Step 7, such as Figure 4 As shown, a hole is drilled on the mobile isolation device 7, and the prepared reactive slurry filling material 10 is filled into the constructed unit space 9 through a pipeline. After the filling, the drilled hole on the mobile isolation device 7 is closed.

[0028] Step 8, such as Figure 4 and Figure 5 As shown, supercritical CO 2 Through the CO with a diameter of 200~700mm 2 The delivery pipe 12 is injected into the unit space 9, and reacts with the reactive slurry filling material 10 to produce a mineralization reaction, thereby achieving CO 2 of storage.

[0029] Among them, the main components of fly ash and gasification ash in the reactive slurry filling material are alkaline metal oxides such as CaO and MgO, which can react with CO after hydration. 2 Double decomposition reaction occurs to generate carbonate, realizing CO 2 The mineralization reaction equation is: CaO+H 2 O=Ca(OH) 2 , Ca(OH)2 +CO 2 =CaCO 3 MgO+H 2 O=Mg(OH) 2 , Mg(OH) 2 +CO 2 =MgCO 3 .

[0030] In the above steps, the outer diameter of the conveying pipeline of the filling material is 100~400mm, and the hole diameter of the grouting borehole and the filling borehole is 100~500mm.

[0031] Embodiment 1: See also Figure 1 , Figure 2 , Figure 3 , Figure 4 and Figure 5 , coal-based solid waste and CO 2 The collaborative filling and sealing process is carried out in the following steps: Step 1, prepare three functional coal-based filling materials, the first one is a paste filling material, the second one is a strong adhesive slurry filling material, and the third one is a reactive slurry filling material.

[0032] Step 2, such as Figure 1 As shown, a short-wall continuous mining and filling working face is designed and arranged, with a dip length of 80m and a strike length of 200m. Cutting eye 2, working face transport drift 3, working face return air drift 4, return air main tunnel 5 and transport main tunnel 6 are excavated to form a transport and ventilation system. Step 3, such as Figure 1 As shown in the figure, the short-wall continuous mining and filling working face is divided into 25 strips 1 along the direction parallel to the cutting eye 2. a According to the geological conditions of the coal seam, 5m is selected, and strip 1 is numbered in sequence from the opening hole 2 to the stop line, numbered as ①, ②, ③... ; Step 4, such as Figure 2 As shown in the figure, starting from strip ①, mining is carried out every three strips, that is, the strips are mined in sequence, numbered as ①, ⑤, ⑨, Each strip is mined from the transport chute 3 to the return air chute 4. After each strip is mined, a mobile isolation device 7 is used to seal the two ends of the mined strip, and a pipeline is used to fill the prepared paste filling material 8 into the strip tunnel after mining; Step 5, such as Figure 3As shown, after the paste filling material 8 filled in step 4 solidifies to the required strength, the same mining process as in step 4 is used to sequentially mine the three strips left between every two paste filling materials 8. After mining, the two ends of the width of the three strips are sealed with a mobile isolation device 7, thereby forming a plurality of closed unit spaces 9; Step 6, such as Figure 5 As shown, a strong adhesive slurry filling material 11 is used to inject grout to seal the cracks and separation spaces 13 in the overlying rock formation above the closed unit space 9, thereby improving the overlying rock strength and airtightness; Step 7, such as Figure 4 As shown, a hole is drilled on the mobile isolation device 7, and the prepared reactive slurry filling material 10 is filled into the constructed unit space 9 through a pipeline. After the filling, the drilled hole on the mobile isolation device 7 is closed; Step 8, such as Figure 4 , Figure 5 As shown, supercritical CO 2 Through the 500mm diameter CO 2 The delivery pipe is injected into the unit space 9, and a mineralization reaction occurs with the reactive slurry filling material 10 to achieve CO 2 of storage.

[0033] Embodiment 2: In this example, coal-based solid waste and CO 2 The collaborative filling and sealing process first designs and arranges a short-wall continuous mining and filling working face, and divides the working face into two parts parallel to the cutting direction. n strips; then starting from the first strip, each m The strips are mined, and the strips are closed after mining, and the paste filling materials are used to fill the strip tunnels after mining; the gaps left between each two paste filling materials are mined in turn. m After mining, the strip is closed. m strips to form several closed unit spaces; use strong adhesive slurry filling materials to inject grout to seal the cracks and delamination spaces in the overlying rock strata of the unit space; finally, fill the reactive slurry filling materials into the constructed unit space, and then supercritical CO 2 Injected into the unit space, it reacts with the reactive slurry filling material to produce a mineralized reaction, achieving CO 2 of storage.

[0034] Embodiment 3: In this example, coal-based solid waste and CO 2 The collaborative filling and sealing process is implemented in the following steps: Step 1, preparing a paste filling material, a strong adhesive slurry filling material and a reactive slurry filling material; Step 2: Design and arrange the short-wall continuous mining and filling working face, and excavate the cutting eye, working face transportation chute, working face return air chute, return air main lane and transportation main lane to form a transportation and ventilation system; Step 3: Divide the short-wall continuous mining and filling working surface into n strips; Step 4: Start from the strip adjacent to the cut eye and cut each m After the strips are mined, the two ends of the strips are sealed with a mobile isolation device, and the paste filling material is filled into the strip tunnel after mining; Step 5: After the paste filling material filled in step 4 solidifies, the remaining paste filling material between each two paste filling materials is collected in turn. m strips, and then use mobile isolation devices to separate the mined m The two ends of each strip are closed to form a number of closed unit spaces; Step 6: Use a strong adhesive slurry filling material to inject grout to seal the cracks and delamination spaces in the overlying rock strata of the unit space; Step 7, drilling a hole on the mobile isolation device, and filling the reactive slurry filling material into the constructed unit space through a pipeline. After filling, the drilled hole on the mobile isolation device is closed; Step 8: Supercritical CO 2 By CO 2 The delivery pipe is injected into the unit space to react with the reactive slurry filling material to achieve CO 2 of storage.

[0035] Embodiment 4: On the basis of Example 3, the paste filling material is prepared from the following raw material components according to mass percentage: 58% coal gangue, 10% cement, 10% fly ash, 2% additives and 20% water; the strong adhesive slurry filling material is prepared from the following raw material components according to mass percentage: 68% coal gangue, 2% additives and 30% water; the reactive slurry filling material is prepared from the following raw material components according to mass percentage: 48% alkaline coal-based solid waste, 2% additives and 50% water.

[0036] Embodiment 5: On the basis of Example 4, the dip length of the short-wall continuous mining and filling working face is 80 to 120 m, and the strike length is 100 to 2000 m.

[0037] The width of the strip is 3~6m.

[0038] Embodiment 6: On the basis of Example 5, the strip mining equipment is a continuous miner, a fully mechanized excavator or an anchor-drilling unit. During the strip mining process, the surrounding rock of the tunnel formed behind needs to be supported.

Claims

1. A coal-based solid waste and CO2 synergistic filling and storage process, characterized in that: First, a short-wall continuous mining and filling working face is designed and arranged, and the working face is divided into n strips; then starting from the first strip, each m The strip is mined, the strip is closed after mining, and the paste filling material is used to fill the strip roadway after mining; The remaining space between each two paste filling materials is mined in sequence. m After mining, the strip is closed. m Strips form several closed unit spaces; Use strong adhesive slurry filling materials to spray grout to seal the cracks and delamination spaces in the overlying rock strata of the unit space; finally, fill the constructed unit space with reactive slurry filling materials, and then inject supercritical CO2 into the unit space to undergo mineralization reaction with the reactive slurry filling materials to achieve CO2 storage.

2. The coal-based solid waste and CO2 synergistic filling and storage process according to claim 1 is characterized in that: Follow the steps below to implement it: Step 1, preparing a paste filling material, a strong adhesive slurry filling material and a reactive slurry filling material; Step 2: Design and arrange the short-wall continuous mining and filling working face, and excavate the cutting eye, working face transportation chute, working face return air chute, return air main lane and transportation main lane to form a transportation and ventilation system; Step 3: Divide the short-wall continuous mining and filling working surface into n strips; Step 4: Start from the strip adjacent to the cut eye, m After the strips are mined, the two ends of the strips are sealed with a mobile isolation device, and the paste filling material is filled into the strip tunnel after mining; Step 5: After the paste filling material filled in step 4 solidifies, the remaining paste filling material between each two paste filling materials is collected in turn. m strips, and then use mobile isolation devices to separate the mined m The two ends of each strip are closed to form a number of closed unit spaces; Step 6: Use a strong adhesive slurry filling material to inject grout to seal the cracks and delamination spaces in the overlying rock strata of the unit space; Step 7, drilling a hole on the mobile isolation device, and filling the reactive slurry filling material into the constructed unit space through a pipeline. After filling, the drilled hole on the mobile isolation device is closed; Step 8: Inject supercritical CO2 into the unit space through the CO2 delivery pipe to undergo a mineralization reaction with the reactive slurry filling material to achieve CO2 storage.

3. The coal-based solid waste and CO2 synergistic filling and storage process according to claim 1 or 2, characterized in that: The paste filling material is prepared from the following raw material components according to mass percentage: 58% coal gangue, 10% cement, 10% fly ash, 2% additives and 20% water; the strong adhesive slurry filling material is prepared from the following raw material components according to mass percentage: 68% coal gangue, 2% additives and 30% water; the reactive slurry filling material is prepared from the following raw material components according to mass percentage: 48% alkaline coal-based solid waste, 2% additives and 50% water.

4. The coal-based solid waste and CO2 synergistic filling and storage process according to claim 1 or 2, characterized in that: The dip length of the short-wall continuous mining and filling working face is 80 to 120 m, and the strike length is 100 to 2000 m.

5. The coal-based solid waste and CO2 synergistic filling and storage process according to claim 1 or 2, characterized in that: The width of the strip is 3 to 6 m.

6. The coal-based solid waste and CO2 synergistic filling and storage process according to claim 1 or 2, characterized in that: Strip mining equipment includes continuous mining machine, multi-purpose excavator or anchor mining unit.

7. The coal-based solid waste and CO2 synergistic filling and storage process according to claim 1 or 2, characterized in that: During the strip mining process, the surrounding rock of the tunnel formed behind must be supported.

8. The coal-based solid waste and CO2 synergistic filling and storage process according to claim 2 is characterized in that: The outer diameter of the conveying pipeline for filling materials is 100~400mm, and the hole diameter of grouting borehole and filling borehole is 100~500mm.

9. The coal-based solid waste and CO2 synergistic filling and storage process according to claim 2 is characterized in that: In step 8, the diameter of the CO2 delivery pipe is 200~700mm.

Images