CN113006862A

CN113006862A - Novel technology for treating coal mining subsidence area by backfilling from ground drilling

Info

Publication number: CN113006862A
Application number: CN202110331236.3A
Authority: CN
Inventors: 张连杰
Original assignee: Individual
Current assignee: Individual
Priority date: 2021-03-29
Filing date: 2021-03-29
Publication date: 2021-06-22

Abstract

The invention relates to a novel technology for treating a coal mining subsidence area through ground drilling and backfilling, which is characterized in that a plurality of grouting drill holes are drilled on the ground along the trend of a goaf at certain intervals to the underground goaf before the goaf is not sunk. And sorting and crushing the ground gangue to sand and pouring the sand and the fly ash of the power plant into the artificial pond. And stirring and sucking by a sand suction pump, and adjusting the solid-liquid ratio by a controllable water diversion sieve to be poured into the underground goaf from the grouting drill hole. Because each goaf is provided with a coal pillar and a closed wall when the goaf is closed, the injected gangue mortar can form a good support rock stratum in the goaf. Thereby keeping the original supporting stress unchanged, effectively controlling the ground not to sink or to sink less and not influencing the farming operation. Compared with the existing underground filling and ground gangue back filling, the invention has essential difference. The drilling filling has the advantages of labor saving, time saving, quick effect, simple, reliable and high efficiency. A large amount of land resources can be saved for the country every year, and the ecological environment is protected from being damaged to benefit mankind.

Description

Novel technology for treating coal mining subsidence area by backfilling from ground drilling

Technical Field

The invention relates to a novel technology for treating a coal mining subsidence area by backfilling from a ground drilled hole, in particular to a novel technology which is invented for overcoming the defect of poor single effect of the conventional coal mining subsidence area treatment method. Belongs to the field of homeland resource and ecological environment protection.

Background

With the exploitation of large-scale modern technology in coal industry, more than 2 million hectares of high-quality land in China become wide ditches and lakes due to the collapse of coal mine goafs every year. The discharged gangue cannot be accumulated like a mountain after being treated on the ground, and the discharged gangue occupies a large amount of land resources in China like the fly ash in a power plant. The existing underground filling and ground gangue transporting backfilling is high in cost and labor intensity and is difficult to realize. The land is lost again because of the need of covering with a large amount of soil after the ground is sunk and the gangue is backfilled, but the success rate of the method is less than 10 percent, the area of the coal mining sunk area in China currently exceeds more than 7000 square hectares, and the area of the coal mining sunk area in Shanxi province only accounts for one seventh of the total area of the whole province. The villages on the surface of the indiscriminate subsided lakes disappear to force common people to move, and great burden is caused to the country and people. Therefore, the treatment of the coal mine goaf is not easy and can not be carried out only by relocation.

Disclosure of Invention

In order to solve the problems, the invention is realized by the following technical scheme. A coal mine underground and on-ground comparison map is utilized, a plurality of grouting drill holes (1), (2) and (3) are drilled on the ground along the direction of a goaf at certain intervals, the drill holes are drilled at the inclined upper part (6) of the goaf, and pipelines (4) are installed on a water-bearing layer and a quicksand layer for blocking. The method comprises the steps of sorting waste rocks from a ground waste rock mountain, crushing the large waste rock into small blocks by a jaw crusher, crushing the small blocks into sand by a cone crusher, pouring the fly ash of a power plant into an artificial pond together, moving, stirring and sucking the sand by a sand suction pump, feeding the sand into a controllable water diversion sieve to adjust the solid-liquid ratio, removing excessive water, feeding the water into a grouting drill hole through a pipeline, and filling the water into a downhole goaf. Further reducing the occupation of land resources by industrial waste residues. By adopting the invention, the goaf can be effectively filled when the ground of the goaf is not sunk, and the ground is ensured not to be sunk or the farming operation is not influenced by less sinking. The invention can also continuously extend the drill hole to the next layer of goaf for filling, thus achieving the purpose of one hole for multiple purposes.

The gangue mortar has strong self-setting property and better fly ash flowing property, and can form a firm supporting rock stratum in a goaf by being filled into a well through a hundreds of meters of drill holes. A gob with a kilometer trend inclines, is 150 meters long and 4 meters high, and has a full space volume of about 60 ten thousand cubic meters. The problem that 3 thousands of cubes are accumulated in one drilled hole is solved, and the problem can be solved by only one drilled hole in a goaf of rocks falling from surrounding rocks. According to the conventional jaw crusher capacity design on the market at present, the maximum feeding size is 1000 mm, and the production capacity is 1000 tons per hour. The cone crusher has a maximum feed size of 350 mm and a capacity of 1200 tons per hour. The maximum mixing flow of the sand pump is 5000 cubic meters per hour, the mixed concentration of the conveyed solid and liquid can reach 60 percent, and the conveying distance is hundreds of meters. Can completely meet the filling requirement of a large mine on the underground goaf. Because the underground goaf contains gas accumulation, a gas drainage pump is arranged on the second drill hole when the first drill hole performs grouting, and the drainage pump is started to drain the gas when the gas concentration reaches 1 percent, so that the construction safety is ensured. For important ground sections, the drilling distance can be reduced and proper amount of cement is added for reinforcement protection.

Drawings

The following detailed description of specific embodiments of the invention is provided in conjunction with the accompanying drawings

FIG. 1 is a schematic block diagram of a new technical implementation of the invention for backfilling a coal mining subsidence area from a ground borehole

FIG. 2 is a schematic diagram of the position of a hole drilled in the gob strike zone of the invention

FIG. 3 is a schematic view of the inclined hole location of the present invention driven into the downhole goaf

In the figure, (1), (2) and (3) are the first 3 grouting drill holes which are drilled at intervals along the direction of the goaf, (4) the sleeves are installed in a water-bearing layer and a quicksand layer, the drill holes are (5) waste rocks falling from surrounding rocks along the direction of the goaf, (6) the lower end of a goaf inclined plane, (7) the upper end of the goaf inclined plane, and (8) a gas drainage pump)

Detailed Description

In the figure 1, gangue larger than 300 mm is screened by a 300-300 mm mesh screen near a gangue dump and enters a jaw crusher to be crushed, and gangue smaller than 300 mm directly enters a cone crusher to be crushed into sand. During the crushing process, a plurality of soft waste rocks are crushed into mud, the mud and the fly ash are added into an artificial pond together, the mud is moved by a sand suction pump, stirred and sucked out and sent into a controllable water sieve, redundant water can be removed by adjusting holes and inclination angles of the controllable water sieve, and the adjusted waste rock mortar enters a grouting drill hole along a pipe groove and is backfilled to an underground goaf.

In fig. 2 the first borehole (1) can be doubled back 50 m from the goaf boundary because the borehole slurry will run to both sides. The number of the drilled holes and the solid-liquid ratio can be adjusted in time according to the grouting amount.

In fig. 3 it is shown that all the boreholes are drilled in the upper part (7) of the goaf for the purpose of rapid filling with gangue fly ash slurry. The poured gangue fly ash mortar is deposited around the drilled hole of the goaf due to the dead weight ratio, and redundant water is discharged from the water discharge port of the sealing wall of the lower wind tunnel to the shaft bottom main tunnel and enters the sump. When underground drainage is inconvenient, high-water-speed solidification expansion auxiliary materials can be added into the grouting material.

The underground goaf can be filled before the ground is not sunk by implementing the technology of the invention, so that the original supporting stress of the goaf is kept unchanged, and the ground is ensured not to be sunk or to be sunk less so as not to influence the farming operation. The technical scheme is designed to have simple and reliable production flow of process equipment, labor and time saving and high efficiency, and can reduce the spacing between drilled holes and mix proper amount of cement for strengthening protection on important ground sections. A large amount of high-quality cultivated land can be saved for the country every year, and huge gangue hills and power plant fly ash can be treated at the same time, so that the ecological environment is protected, and beautiful home is protected.

Claims

1. A new technology for treating a coal mining subsidence area by backfilling from a ground borehole comprises the following steps of; a plurality of grouting drill holes (1), (2) and (3) are drilled on the ground along the direction of a goaf at certain intervals, the drill holes are drilled at the inclined upper part (6) of the goaf, pipelines (4) are installed on a water-bearing layer and a quicksand layer, the method is that ground gangue is crushed into sand which is thrown into an artificial pond, the sand is pumped into the goaf underground through a sand suction pump and a controllable water diversion screen, and the grouting drill holes are drilled.

2. The invention relates to a novel technology of claim 1, which overcomes the defects that a large amount of soil is taken for re-cultivation after the ground is sunk and the gangue is transported from a gangue dump and backfilled, which is labor-consuming, time-consuming and low in efficiency.

3. A technology for treating the subsidence area of coal mining by drilling and backfilling on ground features that the large gangue blocks are broken by jaw crusher and the small gangue blocks are broken by cone crusher, or the powdered coal ash from power plant is used by stirring in pond, and the auxiliary material of high-water-speed solidifying and expanding foaming agent is added when the water drainage is not convenient.

4. The novel technology for treating the coal mining subsidence area through ground drilling backfill according to the claim 1, wherein a grouting drill hole can also extend downwards to the next coal seam goaf to continue grouting and filling the next coal seam goaf, the grouting hole (2) exhausts during grouting of the grouting hole (1), the grouting hole (3) exhausts during grouting of the grouting hole (2), and the like, so that the drilling distance of the section can be properly reduced and cement is added for enhancing protection in important ground sections.

5. The exhaust bore according to claim 4 equipped with a mobile gas pump, the pump being activated when the gas in the exhaust hole exceeds a threshold, and cement can be added to seal the hole just before the completion of the grouting.

6. The gangue powder and fly ash filler as claimed in claim 3, which may be other crushed materials of construction and industrial domestic garbage.