CN114233380B - Method for isolating, grouting and filling overlying strata by using coal-based solid wastes - Google Patents
Method for isolating, grouting and filling overlying strata by using coal-based solid wastes Download PDFInfo
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- CN114233380B CN114233380B CN202111611132.4A CN202111611132A CN114233380B CN 114233380 B CN114233380 B CN 114233380B CN 202111611132 A CN202111611132 A CN 202111611132A CN 114233380 B CN114233380 B CN 114233380B
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- overburden
- coal
- grouting
- slurry
- filling
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- 239000003245 coal Substances 0.000 title claims abstract description 75
- 238000011049 filling Methods 0.000 title claims abstract description 49
- 239000002910 solid waste Substances 0.000 title claims abstract description 12
- 238000000034 method Methods 0.000 title claims abstract description 10
- 239000002002 slurry Substances 0.000 claims abstract description 53
- 239000000843 powder Substances 0.000 claims abstract description 34
- 239000010881 fly ash Substances 0.000 claims abstract description 21
- 238000002955 isolation Methods 0.000 claims abstract description 18
- 238000002156 mixing Methods 0.000 claims abstract description 5
- 230000006641 stabilisation Effects 0.000 claims abstract description 5
- 238000011105 stabilization Methods 0.000 claims abstract description 5
- 239000011435 rock Substances 0.000 claims description 12
- 239000010883 coal ash Substances 0.000 claims description 7
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 6
- 239000002245 particle Substances 0.000 claims description 5
- 230000005484 gravity Effects 0.000 claims description 3
- 239000000463 material Substances 0.000 abstract description 7
- 238000005516 engineering process Methods 0.000 abstract description 5
- 230000018109 developmental process Effects 0.000 abstract description 2
- 238000003912 environmental pollution Methods 0.000 abstract description 2
- 230000000977 initiatory effect Effects 0.000 abstract description 2
- 238000005065 mining Methods 0.000 description 5
- 238000001556 precipitation Methods 0.000 description 3
- 238000002485 combustion reaction Methods 0.000 description 2
- 239000002699 waste material Substances 0.000 description 2
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 229910052799 carbon Inorganic materials 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 239000004570 mortar (masonry) Substances 0.000 description 1
- 230000001603 reducing effect Effects 0.000 description 1
- 230000002269 spontaneous effect Effects 0.000 description 1
Classifications
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH DRILLING; MINING
- E21F—SAFETY DEVICES, TRANSPORT, FILLING-UP, RESCUE, VENTILATION, OR DRAINING IN OR OF MINES OR TUNNELS
- E21F15/00—Methods or devices for placing filling-up materials in underground workings
- E21F15/005—Methods or devices for placing filling-up materials in underground workings characterised by the kind or composition of the backfilling material
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH DRILLING; MINING
- E21F—SAFETY DEVICES, TRANSPORT, FILLING-UP, RESCUE, VENTILATION, OR DRAINING IN OR OF MINES OR TUNNELS
- E21F15/00—Methods or devices for placing filling-up materials in underground workings
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02W—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT
- Y02W30/00—Technologies for solid waste management
- Y02W30/50—Reuse, recycling or recovery technologies
- Y02W30/91—Use of waste materials as fillers for mortars or concrete
Abstract
The invention relates to a method for filling a rock-covered isolation grouting by coal-based solid waste, which improves the filling performance of the rock-covered isolation grouting of gangue powder by adding fly ash and coal slime according to different properties of the coal gangue, fly ash and coal slime in the coal-based solid waste during the filling of the rock-covered isolation grouting, and can improve the fluidity of the gangue powder and reduce the settling rate of the gangue powder when the fly ash and the coal slime reach a certain ratio. Furthermore, the invention divides the isolated grouting filling of the overlying strata into four stages of initiation, development, stabilization and termination according to the state of the overlying strata space, and proposes that the isolated grouting filling of the overlying strata is carried out by adopting different mixing proportions at different stages of the isolated grouting filling of the overlying strata according to the development characteristics of cracks under the overlying strata and the flow characteristics of slurry during grouting of the four stages; solves the application problem of gangue in grouting filling, and can effectively improve the dilemma of insufficient material of the overlying strata isolation grouting filling technology and the dilemma of occupation of land and environmental pollution of gangue.
Description
Technical Field
The invention belongs to the field of green mining of mining engineering, and particularly relates to a method for filling overlying strata by using coal-based solid wastes in isolation grouting.
Background
The development of coal exploitation industry in China is always hindered by building (construction) of building coal, and especially in the middle eastern region of China, the exploitation of building coal under the coal is of great significance for releasing coal resources, relieving contradiction between resource exploitation and human living and protecting environment. The green mining technology of the overlying strata isolated grouting filling has the advantages of remarkable sinking reducing effect, economy and reasonability, and obtains a great amount of application, but the original grouting filling material is in short supply and the price is increased. Gangue is waste produced in coal mining, has low carbon content and poor combustion performance, and is mostly treated as waste stacking, so that the gangue occupies a large amount of land and has the risks of spontaneous combustion and the like. The coal gangue is used as a substitute material for the cover rock isolation grouting filling green mining technology, so that the problem of insufficient supply of the filling material in the technology can be solved, and meanwhile, the problems of stacking and pollution of the coal gangue can be solved. Therefore, a method for isolating, grouting and filling the overburden rock by using the coal-based solid waste is needed to be formed, and the problems of coal gangue stacking and pollution and the shortage of grouting and filling materials are solved.
Disclosure of Invention
Aiming at the defects in the prior art, the invention provides a method for filling the overlying strata by using coal-based solid waste for isolating grouting, wherein coal gangue is crushed into coal gangue powder, the coal gangue powder, fly ash and coal slime are mixed and then added into water to prepare grouting slurry, and grouting filling is carried out at different stages of the overlying strata by adopting different mixing proportions;
in the initial stage of the isolation grouting filling of the overburden, an unfilled or unfilled overburden space exists in the overburden, a large amount of slurry is required to be quickly injected, the subsidence of an overburden layer on the overburden space is restrained, and at the moment, the mass ratio of gangue powder, fly ash and coal slime in the injected slurry is (6-8): (2-4): 0;
in the development stage of the isolation grouting filling of the overburden, namely in the initial stage of filling the overburden space with slurry, the grouting pressure in the overburden space is smaller than the gravity of the overburden layer, the collapsed rock begins to be compressed, the fluidity of the slurry injected into the overburden space is reduced, coal slime is required to be added into coal gangue powder and coal slime slurry to increase the fluidity, and the mass ratio of the coal gangue powder, the coal ash and the coal slime in the injected slurry is (4-5): (2-4): (2-4);
in the isolated grouting filling stabilization stage of the overburden, namely after the overburden space is filled with slurry for a period of time, the overburden space is gradually enlarged under the drive of high-pressure slurry, the grouting pressure at the overburden space and the overburden layer generate stress balance, the caving rock in the middle of the goaf is gradually compacted to a certain extent, the fluidity of the slurry injected into the overburden space is continuously reduced, the amount of gangue powder and fly ash in the slurry is required to be reduced again, the amount of coal slime is increased, and the mass ratio of the gangue powder, the fly ash and the coal slime in the injected slurry is (3-5): (1-3): (3-5);
in the final stage of the isolation grouting filling of the overburden, the overburden space is further expanded, the collapsed rock in the middle of the goaf is further compacted, so that the pressure of the slurry injected into the overburden space is larger than the stress generated by the overburden layer, the overburden layer starts to arch, the fluidity of the slurry injected into the overburden space is further reduced, the ratio of coal slime in the slurry needs to be further improved, and the mass ratio of gangue powder, coal ash and coal slime in the injected slurry needs to be kept at (1-2): (2-4): (5-7).
Preferably, the particle size of the gangue powder is 0.5-1.5mm, the fly ash and the coal slime need to pass through a square hole sieve with the particle size smaller than or equal to 2mm, and the mass ratio of water in the injected slurry is smaller than 40%.
The beneficial effects are that: according to the invention, the research shows that the coal gangue, the fly ash and the coal slime in the coal-based solid waste have different properties when the overlying strata are isolated and grouting and filled, the coal gangue powder has the characteristics of large precipitation rate and poor fluidity, the coal gangue powder is not good when being independently used as the overlying strata isolated and grouting and filling material, the fly ash has the characteristics of moderate fluidity and precipitation rate, and the coal slime has the characteristics of excellent fluidity and precipitation rate; therefore, the overlying strata isolation grouting filling performance of the gangue powder is improved by adding the fly ash and the coal slime, and when the fly ash and the coal slime reach a certain ratio, the fluidity of the gangue powder can be improved, and the settling rate of the gangue powder can be reduced. Furthermore, the invention creatively divides the isolated grouting filling of the overlying strata into four stages of initiation, development, stabilization and termination according to the state of the overlying strata space, and proposes that the isolated grouting filling of the overlying strata is carried out by adopting different mixing proportions in different stages of the isolated grouting filling of the overlying strata according to the development characteristics of the space under the overlying strata and the flow characteristics of the slurry during grouting in the four stages; solves the application problem of gangue in grouting filling, and can effectively improve the dilemma of insufficient material of the overlying strata isolation grouting filling technology and the dilemma of occupation of land and environmental pollution of gangue.
Drawings
FIG. 1 is a schematic diagram of a method of using coal-based solid wastes for overburden isolation grouting filling in accordance with the present invention;
in the figure: 1-overburden space; 2-collapse of the rock; 3-lower strata; 4-overburden; 5-slurry.
Detailed Description
The technical scheme of the invention is described in more detail below with reference to the accompanying drawings in the embodiments of the invention.
As shown in figure 1, the method for filling the overlying strata by grouting the solid waste of the coal base is characterized in that the coal gangue is crushed into coal gangue powder with the particle size of 0.5-1.5mm, the coal gangue powder, the coal ash and the coal slime are mixed and then added into water to prepare slurry for grouting, and grouting filling is carried out at different stages of filling by grouting the overlying strata by adopting different mixing proportions; wherein the fly ash and the coal slime pass through a square hole sieve with the diameter of less than or equal to 2mm, and the mass ratio of water in the injected slurry is less than 40 percent;
in the initial stage of the isolation grouting filling of the overburden, an unfilled or unfilled overburden space 1 exists in the overburden, a large amount of slurry needs to be quickly injected, the subsidence of an overburden layer 4 on the overburden space is restrained, and at the moment, the mass ratio of gangue powder, fly ash and coal slime in the injected slurry is (6-8): (2-4): 0;
in the development stage of the isolation grouting filling of the overburden, namely in the initial stage of filling the overburden space 1 with the slurry 5, the grouting pressure in the overburden space 1 is smaller than the gravity of the overburden layer 4, the collapsed rock 2 begins to be compressed, the fluidity of the slurry injected into the overburden space 1 is reduced, the fluidity is increased by adding coal slime into gangue powder and powdered coal mortar, and at the moment, the mass ratio of the gangue powder, the coal ash and the coal slime in the injected slurry is (4-5): (2-4): (2-4);
in the isolated grouting filling stabilization stage of the overburden, namely after the overburden space 1 is filled with slurry for a period of time, the overburden space 1 is gradually enlarged under the drive of high-pressure slurry, the grouting pressure at the overburden space 1 and the overburden layer 4 generate stress balance, the collapsed rock 2 in the middle of the goaf is gradually compacted to a certain degree, the fluidity of the slurry injected into the overburden space 1 is continuously reduced, the amount of gangue powder and fly ash in the slurry is required to be reduced again, the amount of coal slime is increased, and the mass ratio (3-5) of the gangue powder, the fly ash and the coal slime in the injected slurry is: (1-3): (3-5);
in the final stage of the isolation grouting filling of the overburden, the overburden space is further expanded, the collapsed rock 2 in the middle of the goaf is further compacted, so that the pressure of the slurry 5 injected into the overburden space 1 is larger than the stress generated by the overburden layer 4, the overburden layer 4 starts to arch, the fluidity of the slurry injected into the overburden space 1 is further reduced, the proportion of coal slime in the slurry needs to be further improved, and at the moment, the mass ratio of gangue powder, fly ash and coal slime in the injected slurry needs to be kept at (1-2): (2-4): (5-7).
Claims (2)
1. A method for filling the insulating grouting of the overlying strata by using the solid waste of coal base is characterized in that the coal gangue is crushed into coal gangue powder, and the coal gangue powder, the coal ash and the coal slime are mixed and then added into water to prepare grouting slurry, and different mixing proportions are adopted for grouting and filling in different stages of the insulating grouting filling of the overlying strata;
in the initial stage of the isolation grouting filling of the overburden, an unfilled or unfilled overburden space exists in the overburden, a large amount of slurry is required to be quickly injected, the subsidence of an overburden layer on the overburden space is restrained, and at the moment, the mass ratio of gangue powder, fly ash and coal slime in the injected slurry is (6-8): (2-4): 0;
in the development stage of the isolation grouting filling of the overburden, namely in the initial stage of filling the overburden space with slurry, the grouting pressure in the overburden space is smaller than the gravity of the overburden layer, the collapsed rock begins to be compressed, the fluidity of the slurry injected into the overburden space is reduced, coal slime is required to be added into coal gangue powder and coal slime slurry to increase the fluidity, and the mass ratio of the coal gangue powder, the coal ash and the coal slime in the injected slurry is (4-5): (2-4): (2-4);
in the isolated grouting filling stabilization stage of the overburden, namely after the overburden space is filled with slurry for a period of time, the overburden space is gradually enlarged under the drive of high-pressure slurry, the grouting pressure at the overburden space and the overburden layer generate stress balance, the caving rock in the middle of the goaf is gradually compacted to a certain extent, the fluidity of the slurry injected into the overburden space is continuously reduced, the amount of gangue powder and fly ash in the slurry is required to be reduced again, the amount of coal slime is increased, and the mass ratio of the gangue powder, the fly ash and the coal slime in the injected slurry is (3-5): (1-3): (3-5);
in the final stage of the isolation grouting filling of the overburden, the overburden space is further expanded, the collapsed rock in the middle of the goaf is further compacted, so that the pressure of the slurry injected into the overburden space is larger than the stress generated by the overburden layer, the overburden layer starts to arch, the fluidity of the slurry injected into the overburden space is further reduced, the ratio of coal slime in the slurry needs to be further improved, and the mass ratio of gangue powder, coal ash and coal slime in the injected slurry needs to be kept at (1-2): (2-4): (5-7).
2. The method for filling the overlying strata isolated grouting by using the coal-based solid waste according to claim 1, wherein the particle size of the gangue powder is 0.5-1.5mm, the fly ash and the coal slime need to pass through square hole sieves with the particle size of less than or equal to 2mm, and the mass ratio of water in the injected slurry is less than 40%.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111611132.4A CN114233380B (en) | 2021-12-27 | 2021-12-27 | Method for isolating, grouting and filling overlying strata by using coal-based solid wastes |
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| CN202111611132.4A CN114233380B (en) | 2021-12-27 | 2021-12-27 | Method for isolating, grouting and filling overlying strata by using coal-based solid wastes |
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| CN114233380A CN114233380A (en) | 2022-03-25 |
| CN114233380B true CN114233380B (en) | 2023-12-05 |
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| CN114562330B (en) * | 2022-04-02 | 2022-11-08 | 中国矿业大学 | Method for controlling diffusion range of filling slurry for overburden rock isolation grouting |
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