CN111978063A - Underground goaf filling roof-contacting expanding agent - Google Patents
Underground goaf filling roof-contacting expanding agent Download PDFInfo
- Publication number
- CN111978063A CN111978063A CN202010890338.4A CN202010890338A CN111978063A CN 111978063 A CN111978063 A CN 111978063A CN 202010890338 A CN202010890338 A CN 202010890338A CN 111978063 A CN111978063 A CN 111978063A
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- Prior art keywords
- contacting
- sodium
- expanding agent
- goaf
- powder
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- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
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Links
- 238000011049 filling Methods 0.000 title claims abstract description 24
- 239000000843 powder Substances 0.000 claims abstract description 21
- 239000003795 chemical substances by application Substances 0.000 claims abstract description 19
- 239000010881 fly ash Substances 0.000 claims abstract description 11
- FAPWRFPIFSIZLT-UHFFFAOYSA-M Sodium chloride Chemical compound [Na+].[Cl-] FAPWRFPIFSIZLT-UHFFFAOYSA-M 0.000 claims abstract description 10
- 229910052602 gypsum Inorganic materials 0.000 claims abstract description 9
- 239000010440 gypsum Substances 0.000 claims abstract description 9
- 239000004115 Sodium Silicate Substances 0.000 claims abstract description 7
- 239000001768 carboxy methyl cellulose Substances 0.000 claims abstract description 7
- NTHWMYGWWRZVTN-UHFFFAOYSA-N sodium silicate Chemical compound [Na+].[Na+].[O-][Si]([O-])=O NTHWMYGWWRZVTN-UHFFFAOYSA-N 0.000 claims abstract description 7
- 229910052911 sodium silicate Inorganic materials 0.000 claims abstract description 7
- 235000008733 Citrus aurantifolia Nutrition 0.000 claims abstract description 6
- 235000011941 Tilia x europaea Nutrition 0.000 claims abstract description 6
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 claims abstract description 6
- 239000004571 lime Substances 0.000 claims abstract description 6
- ITCAUAYQCALGGV-XTICBAGASA-M sodium;(1r,4ar,4br,10ar)-1,4a-dimethyl-7-propan-2-yl-2,3,4,4b,5,6,10,10a-octahydrophenanthrene-1-carboxylate Chemical compound [Na+].C([C@@H]12)CC(C(C)C)=CC1=CC[C@@H]1[C@]2(C)CCC[C@@]1(C)C([O-])=O ITCAUAYQCALGGV-XTICBAGASA-M 0.000 claims abstract description 6
- 239000011398 Portland cement Substances 0.000 claims abstract description 5
- DPXJVFZANSGRMM-UHFFFAOYSA-N acetic acid;2,3,4,5,6-pentahydroxyhexanal;sodium Chemical compound [Na].CC(O)=O.OCC(O)C(O)C(O)C(O)C=O DPXJVFZANSGRMM-UHFFFAOYSA-N 0.000 claims abstract description 5
- 229910052782 aluminium Inorganic materials 0.000 claims abstract description 5
- 235000019812 sodium carboxymethyl cellulose Nutrition 0.000 claims abstract description 5
- 229920001027 sodium carboxymethylcellulose Polymers 0.000 claims abstract description 5
- 239000011780 sodium chloride Substances 0.000 claims abstract description 5
- 239000010883 coal ash Substances 0.000 abstract description 4
- 230000007613 environmental effect Effects 0.000 abstract description 3
- 238000005516 engineering process Methods 0.000 abstract description 2
- 238000003912 environmental pollution Methods 0.000 abstract 1
- 239000004568 cement Substances 0.000 description 9
- 239000002002 slurry Substances 0.000 description 9
- 238000000034 method Methods 0.000 description 6
- 238000001035 drying Methods 0.000 description 4
- 239000000203 mixture Substances 0.000 description 4
- 239000002245 particle Substances 0.000 description 4
- 210000004243 sweat Anatomy 0.000 description 4
- 239000002699 waste material Substances 0.000 description 4
- 239000003245 coal Substances 0.000 description 3
- 238000001514 detection method Methods 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- 238000012986 modification Methods 0.000 description 3
- 230000004048 modification Effects 0.000 description 3
- 239000002893 slag Substances 0.000 description 3
- 229920002134 Carboxymethyl cellulose Polymers 0.000 description 2
- 235000010948 carboxy methyl cellulose Nutrition 0.000 description 2
- 239000008112 carboxymethyl-cellulose Substances 0.000 description 2
- 230000007547 defect Effects 0.000 description 2
- 238000005065 mining Methods 0.000 description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 2
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 1
- 238000003723 Smelting Methods 0.000 description 1
- 238000010521 absorption reaction Methods 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000005422 blasting Methods 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 239000002274 desiccant Substances 0.000 description 1
- 230000008034 disappearance Effects 0.000 description 1
- 238000005553 drilling Methods 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 238000000227 grinding Methods 0.000 description 1
- 229910052739 hydrogen Inorganic materials 0.000 description 1
- 239000001257 hydrogen Substances 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000002156 mixing Methods 0.000 description 1
- 238000004806 packaging method and process Methods 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- 230000002787 reinforcement Effects 0.000 description 1
- 239000012744 reinforcing agent Substances 0.000 description 1
- 238000003756 stirring Methods 0.000 description 1
- 239000002562 thickening agent Substances 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B28/00—Compositions of mortars, concrete or artificial stone, containing inorganic binders or the reaction product of an inorganic and an organic binder, e.g. polycarboxylate cements
- C04B28/24—Compositions of mortars, concrete or artificial stone, containing inorganic binders or the reaction product of an inorganic and an organic binder, e.g. polycarboxylate cements containing alkyl, ammonium or metal silicates; containing silica sols
- C04B28/26—Silicates of the alkali metals
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B18/00—Use of agglomerated or waste materials or refuse as fillers for mortars, concrete or artificial stone; Treatment of agglomerated or waste materials or refuse, specially adapted to enhance their filling properties in mortars, concrete or artificial stone
- C04B18/04—Waste materials; Refuse
- C04B18/06—Combustion residues, e.g. purification products of smoke, fumes or exhaust gases
- C04B18/062—Purification products of smoke, fume or exhaust-gases
- C04B18/064—Gypsum
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B18/00—Use of agglomerated or waste materials or refuse as fillers for mortars, concrete or artificial stone; Treatment of agglomerated or waste materials or refuse, specially adapted to enhance their filling properties in mortars, concrete or artificial stone
- C04B18/04—Waste materials; Refuse
- C04B18/06—Combustion residues, e.g. purification products of smoke, fumes or exhaust gases
- C04B18/08—Flue dust, i.e. fly ash
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B24/00—Use of organic materials as active ingredients for mortars, concrete or artificial stone, e.g. plasticisers
- C04B24/24—Macromolecular compounds
- C04B24/38—Polysaccharides or derivatives thereof
- C04B24/383—Cellulose or derivatives thereof
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B38/00—Porous mortars, concrete, artificial stone or ceramic ware; Preparation thereof
- C04B38/02—Porous mortars, concrete, artificial stone or ceramic ware; Preparation thereof by adding chemical blowing agents
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK 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
-
- 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
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Ceramic Engineering (AREA)
- Organic Chemistry (AREA)
- Materials Engineering (AREA)
- Structural Engineering (AREA)
- Environmental & Geological Engineering (AREA)
- Combustion & Propulsion (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Civil Engineering (AREA)
- Mining & Mineral Resources (AREA)
- General Chemical & Material Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Geochemistry & Mineralogy (AREA)
- Geology (AREA)
- Inorganic Chemistry (AREA)
- Curing Cements, Concrete, And Artificial Stone (AREA)
Abstract
The invention discloses a filling roof-contacting expanding agent for an underground goaf, which is prepared from the following components in parts by weight: 40% of portland cement clinker, 35% of fly ash, 15% of dry lime powder, 5% of desulfurized gypsum powder, 1% of sodium chloride, 1% of sodium silicate, 1% of aluminum paste, 1% of sodium abietate and 1% of sodium carboxymethylcellulose. Compared with similar products, the coal ash and the desulfurized gypsum powder are effectively utilized to meet the requirements of national environmental protection science and technology industries, so that the coal ash with serious environmental pollution is changed into valuable to generate economic benefit.
Description
Technical Field
The invention relates to the technical field of coal mining, in particular to a top contacting expanding agent for filling of an underground goaf.
Background
With the increase of the coal mining depth, more and more goafs and empty roadways are reserved, so that disasters such as large land collapse on the ground, landslide, river cutoff, lake disappearance, building collapse and collapse are caused; in particular, the ground goaf of many villages collapses to make the house collapse and cause casualties and great production loss.
At present, in order to solve the problem of collapse of a buried goaf, methods such as a goaf blasting caving collapse method, a goaf top drilling anchor grouting reinforcement method, a gangue filling method and the like are generally adopted for a coal mine to prevent the goaf from collapsing; however, the methods have defects, cannot fill and closely compact the goaf space, and cannot effectively prevent the goaf from collapsing.
Disclosure of Invention
Aiming at the technical defects, the invention aims to provide the goaf filling and roof-contacting expanding agent which is low in cost and convenient to operate and use, the filling expanding agent can be mixed with waste slag, coal ash, various smelting waste residues, gangue residues and the like of a power plant to form slurry, the slurry is injected into the goaf to be filled, and the filling slurry made of the waste residues can expand to contact the roof due to the addition of the filling expanding agent, so that the purpose of expanding and filling the goaf is achieved.
In order to solve the technical problems, the invention adopts the following technical scheme:
the invention provides a filling roof-contacting expanding agent for an underground goaf, which is prepared from the following components in parts by weight: 40% of portland cement clinker, 35% of fly ash, 15% of dry lime powder, 5% of desulfurized gypsum powder, 1% of sodium chloride, 1% of sodium silicate, 1% of aluminum paste, 1% of sodium abietate and 1% of sodium carboxymethylcellulose.
The aluminum powder paste and the sodium abietate powder can be excited by the alkaline function of the dry lime powder to generate chemical reaction in the process of sweat absorption of the cement paste to generate particles, and the particles expand by hydrogen bubbles to fill the cement paste, so that the expansion rate reaches 80%;
the carboxymethyl cellulose is used as a cement slurry thickening agent, so that the viscosity and the consistency of the cement slurry can be increased, and expanded particles generated in the cement slurry are not easy to disperse, so that high-strength framework cement expanded particles are formed;
the sodium silicate powder has high-viscosity gel property, viscosity and quick-drying property, and can be mixed with expansion agent formed from flyash and cement, and ground to synthesize quick-drying expansion agent, so that it can greatly raise activity of flyash, raise cement strength and accelerate sweat-absorbing and quick-drying speed of cement.
The preparation method of the underground goaf filling roof-contacting expanding agent comprises the following steps: mixing 40% of portland cement clinker, 35% of fly ash, 15% of dry lime powder, 5% of desulfurized gypsum powder, 1% of sodium chloride, 1% of sodium silicate, 1% of aluminum paste, 1% of sodium abietate and 1% of sodium carboxymethylcellulose, placing the mixture in a ball mill, grinding the mixture to 200 meshes, drying and packaging, wherein each bag is 25 kg.
The invention has the beneficial effects that:
1. the product is added with 35% of fly ash and 5% of desulfurized gypsum powder to prepare the underground goaf filling roof-contacting expanding agent, compared with similar products: the effective utilization of the fly ash and the desulfurized gypsum powder is in accordance with the national environmental protection science and technology industry, so that the fly ash and the desulfurized gypsum powder which seriously pollute the environment are changed into valuable, and economic benefits and social environmental protection benefits are generated.
2. The' underground goaf filling roof-contacting expanding agent prepared from the sodium silicate powder and the carboxymethyl cellulose as the reinforcing agents and the quick-drying agent has the advantages of high slip property and high fluidity during grouting, is not easy to block a filling pump and a slurry conveying pipe, and has the advantages of good grouting fluidity and difficult occurrence of pump pipe blockage compared with similar products.
3. Compared with the expansion rate of 10% of similar products, the expansion rate of 80% is higher in the underground goaf filling roof-contacting expansion agent developed by the company, and the addition amount of the underground goaf filling expansion agent added when a large amount of waste coal ash powder or gangue slag powder of a power plant is used for filling on a mine is small, so that the filling cost is reduced.
4. In conclusion, the underground goaf filling roof-contacting expanding agent provided by the invention is an environment-friendly novel filling expanding material with low cost and good effect.
Detailed Description
The technical solution of the present invention will be clearly and completely described below with reference to the embodiments of the present invention.
The underground goaf filling roof-contacting expanding agent is prepared from the following components in parts by weight: 40% of portland cement clinker, 35% of fly ash, 15% of dry lime powder, 5% of desulfurized gypsum powder, 1% of sodium chloride, 1% of sodium silicate, 1% of aluminum paste, 1% of sodium abietate and 1% of sodium carboxymethylcellulose.
Performance detection
1. The detection method comprises the following steps: the underground goaf is filled with a roof-contacting expanding agent, fly ash (or gangue slag powder) and water according to the proportion of 10%: 50%: after 40 percent of the mixture is uniformly mixed and stirred, the mixture is conveyed by a filling pump and injected into a goaf, and the effect index is observed and recorded;
2. and (3) detection results:
(1) initial setting time after stirring, conveying and injecting into the goaf: 1-2 hours;
(2) and final setting time after conveying and injecting into the goaf: 12-24 hours;
(3) the expansion rate of the conveying belt after being injected into the goaf and when sweat is collected is less than or equal to 10 percent;
(4) compressive strength after 2 days: not less than 5 MPa;
(5) compressive strength after 7 days: less than or equal to 15 MPa.
And (3) expansion rate test:
1000 ml of underground goaf with fineness of 200 meshes is measured and filled with a roof-contacting expanding agent and placed in a measuring cylinder with measuring range of 3000 ml, 1000 ml of clean water is added, the slurry is uniformly stirred to reach 2000 ml scale and is placed still for 12 hours, the slurry basically expands and absorbs sweat and hardens within the 12 hours, the expansion scale after absorbing sweat and hardening in the measuring cylinder is 2800 ml, and the experiment proves that the expansion rate of the product can reach 80%.
It will be apparent to those skilled in the art that various changes and modifications may be made in the present invention without departing from the spirit and scope of the invention. Thus, if such modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include such modifications and variations.
Claims (1)
1. The underground goaf filling roof-contacting expanding agent is characterized by being prepared from the following components in parts by weight: 40% of portland cement clinker, 35% of fly ash, 15% of dry lime powder, 5% of desulfurized gypsum powder, 1% of sodium chloride, 1% of sodium silicate, 1% of aluminum paste, 1% of sodium abietate and 1% of sodium carboxymethylcellulose.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010890338.4A CN111978063A (en) | 2020-08-29 | 2020-08-29 | Underground goaf filling roof-contacting expanding agent |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010890338.4A CN111978063A (en) | 2020-08-29 | 2020-08-29 | Underground goaf filling roof-contacting expanding agent |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN111978063A true CN111978063A (en) | 2020-11-24 |
Family
ID=73440336
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202010890338.4A Pending CN111978063A (en) | 2020-08-29 | 2020-08-29 | Underground goaf filling roof-contacting expanding agent |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN111978063A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114907138A (en) * | 2022-04-14 | 2022-08-16 | 华南理工大学 | Grouting material for filling underground cavity |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102815963A (en) * | 2012-09-14 | 2012-12-12 | 淄博矿业集团有限责任公司 | High-water-content micro-expansion filling material composition |
| CN103011742A (en) * | 2012-12-05 | 2013-04-03 | 山东科技大学 | Actively-pressing high-swelling pasty filling material |
| CN103373827A (en) * | 2012-04-17 | 2013-10-30 | 都江堰科普达新型材料有限公司 | Cement-based material |
| CN108609964A (en) * | 2018-07-26 | 2018-10-02 | 成都理工大学 | A kind of goaf grouting filler |
-
2020
- 2020-08-29 CN CN202010890338.4A patent/CN111978063A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103373827A (en) * | 2012-04-17 | 2013-10-30 | 都江堰科普达新型材料有限公司 | Cement-based material |
| CN102815963A (en) * | 2012-09-14 | 2012-12-12 | 淄博矿业集团有限责任公司 | High-water-content micro-expansion filling material composition |
| CN103011742A (en) * | 2012-12-05 | 2013-04-03 | 山东科技大学 | Actively-pressing high-swelling pasty filling material |
| CN108609964A (en) * | 2018-07-26 | 2018-10-02 | 成都理工大学 | A kind of goaf grouting filler |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114907138A (en) * | 2022-04-14 | 2022-08-16 | 华南理工大学 | Grouting material for filling underground cavity |
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| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| RJ01 | Rejection of invention patent application after publication | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20201124 |