Testing device and method for disturbing water quality of underground water by grouting

Abstract

The invention relates to the technical field of environmental engineering, in particular to a testing device and method for disturbing the quality of underground water through grouting. The invention provides a test device and method for disturbing the quality of underground water by grouting, which can systematically research and quantify the disturbance degree of consolidation and water release of grout with different slurrying water distributions on the quality of the underground water of an injected aquifer and provide a scientific basis for evaluating and reducing the potential influence of coal mine grouting operation on an underground water environment. The testing device comprises a grouting barrel, a liquid inlet pipe, a liquid outlet pipe and the like, the upper side of the right portion of the grouting barrel is connected with the liquid inlet pipe, and the upper side of the left portion of the grouting barrel is connected with the liquid outlet pipe. The device can systematically research and quantify the disturbance degree of consolidation and water release of slurry with different slurrying water distributions on the quality of underground water in the injected aquifer, and provides a scientific basis for evaluating and reducing the potential influence of coal mine grouting operation on the underground water environment.

Description

Technical Field

[0001] The invention relates to the technical field of environmental engineering, and in particular to a test device and method for disturbing groundwater quality by grouting. Background Art

[0002] Below the bottom plate of the Carboniferous-Permian coal-bearing strata in the North China Coalfield, there is a set of limestone aquifers, namely the Carboniferous Taiyuan Formation limestone (abbreviated as "Taihui") and the Ordovician limestone (abbreviated as "Aohui"). More than 95% of the super-large well flooding accidents in the North China Coalfield are caused by water inrush from the bottom plate limestone.

[0003] In order to ensure safe mining of coal mines, the main technical measure currently taken is to use ground directional drilling technology to carry out regional grouting reinforcement of the Taiyuan Group Three Ash (L3). This can not only increase the thickness of the coal seam floor waterproof layer and its ability to resist the high water pressure of the floor limestone, but also block the water-conducting channels passing through the L3 ash (such as water-conducting faults, karst collapse columns, etc.), with the best technical and economic benefits, and prevent the water-rich and strong Ordovician ash water from filling the mine.

[0004] However, from the grouting practice of coal mines in the North China Coalfield, the grouting volume is particularly large in mining areas with complex structures. Taking a coal mine in the Huaibei mining area as an example, the amount of cement slurry injected is as high as 800,000 tons. The specific gravity of cement slurry is 1.2t / m3, and the water-cement ratio is 3:1, so the water distribution of 800,000 tons of cement slurry is as high as 600,000 m3. While cement slurry is consolidating in the stratum, the amount of water released is considerable. Experiments have shown that the water release rate of cement slurry with a specific gravity of 1.2t / m3 is between 40% and 50%, that is, the water release of 800,000 tons of cement slurry is 320,000 to 400,000 m3 of water. This water enters the Taihui aquifer, which is bound to cause changes in the quality of the original groundwater.

[0005] The water used for grouting is surface water or shallow groundwater, which has poor water quality and is mostly Class V water. A large amount of slurry released water has high alkalinity (pH usually exceeds 12), and the water quality is even worse, which has an important impact on the groundwater quality of the injected aquifer. Especially in some mining areas (such as Huaibei Zhahe mining area, etc.), Taihui groundwater is an important water supply source for the mining area. Therefore, the study of the response characteristics of the water quality of the injected aquifer to the regional grouting reinforcement disturbance has important practical significance.

[0006] This research is difficult to solve on site. Only through experiments can we obtain the degree of disturbance of the water quality of the aquifer caused by grouting in the bottom limestone area, so as to achieve the dual effects of coal mine water hazard prevention and groundwater environmental protection. Therefore, from the perspective of groundwater environment protection, especially drinking groundwater environmental protection, coal mines urgently need to develop a device and test method to clarify the disturbance characteristics of the groundwater quality of the injected aquifer caused by the consolidation and water release of slurries with different slurry preparations. Summary of the invention

[0007] In order to overcome the shortcomings of the above-mentioned background technology, the present invention provides a test device and method for grouting disturbance of groundwater quality, which can systematically study and quantify the degree of disturbance of groundwater quality in the injected aquifer caused by consolidation and water release of slurry with different slurrying and water distribution, and provide a scientific basis for evaluating and reducing the potential impact of coal mine grouting operations on the groundwater environment.

[0008] The technical solution is: a test device and method for grouting disturbance of groundwater quality, including a grouting bucket, a liquid inlet pipe, a liquid outlet pipe, a bracket, a test bench, a cylinder, a sedimentation tube, a water outlet pipe and a casing, the upper right side of the grouting bucket is connected to the liquid inlet pipe, the upper left side of the grouting bucket is connected to the liquid outlet pipe, a bracket is provided on the left side of the grouting bucket, a test bench is provided on the left side of the bracket, the upper left sides of the front and rear parts of the test bench are connected to the cylinder, a sedimentation tube is connected between the telescopic ends of the cylinder, the lower left side of the sedimentation tube is connected to the water outlet pipe, and the left part of the water outlet pipe is slidably connected to the casing.

[0009] Furthermore, the bracket includes a mud pump, an infusion tube, a connecting tube, a first valve and a sealing sleeve. The mud pump is connected to the top of the bracket, the infusion tube is connected between the right side of the mud pump and the outlet tube, the connecting tube is connected to the left side of the mud pump, the connecting tube is provided with a first valve, and the sealing sleeve is connected to the left side of the connecting tube. The mud pump transports the mud in the grouting bucket to the connecting tube through the infusion tube and the outlet tube. By opening the first valve, the mud in the connecting tube can be sent to the left.

[0010] Furthermore, the test bench includes a servo motor, a bidirectional screw, a sliding seat, a rock tube and an injection hole plug. The right part of the test bench is connected to the servo motor, and the bidirectional screw is connected to the output shaft of the servo motor. The bidirectional screw is rotatably connected to the test bench. The front and rear parts of the test bench are slidably connected to the sliding seats, and the sliding seats are threadedly connected to the bidirectional screw. The tops of the sliding seats are connected to the rock tubes, and injection hole plugs are provided between the tops of the rock tubes. The left parts of the rock tubes are in contact with the sealing sleeves. The rotation of the servo motor output shaft drives the screw to rotate, and the rotation of the screw controls the sliding seats to move away from or closer to each other. The rock tubes are close to each other and closed to form a sealed space. The actual geological conditions and environment are simulated by pulling out the injection hole plugs, filling the rock tube with groundwater samples and placing specific types of rocks.

[0011] Furthermore, seepage holes are opened on the left side of the rock tube.

[0012] Furthermore, the sedimentation cylinder includes an exhaust hole plug and a mud discharge hole plug. The top of the sedimentation cylinder is provided with an exhaust hole plug for discharging gas, and the bottom of the sedimentation cylinder is provided with a mud discharge hole plug for discharging mud particles.

[0013] Furthermore, the water outlet pipe includes a second valve. The water outlet pipe is provided with a second valve.

[0014] Furthermore, the casing includes an online monitoring device for water physical indicators, a third valve and a sampling tube. The top of the casing is connected to an online monitoring device for water physical indicators for monitoring the material properties of the mixture of grouting water and groundwater. The left part of the casing is provided with a third valve, and the left part of the third valve is connected to a sampling tube for outputting the mixed liquid for convenient sampling.

[0015] Furthermore, it also includes a collecting tube, and a collecting tube for collecting the derived liquid is arranged on the lower left side of the sampling tube.

[0016] Furthermore, a control panel is included. The front side of the upper part of the test bench is provided with a control panel for controlling the motor, the mud pump and the cylinder.

[0017] Further, the method further comprises the following steps:

[0018] Step 1: In the preparation stage, the groundwater taken from the field is injected into the rock tube at the injection hole plug until the sedimentation tube stops overflowing, and then the vent hole plug, mud discharge hole plug and injection hole plug are closed, and the groundwater in the rock tube is allowed to stand for a week to simulate the real groundwater environment;

[0019] Step 2: Initial detection. Before the test, open the second valve (half-open), and the groundwater in the sedimentation cylinder flows into the outlet pipe and enters the casing through the outlet pipe. The initial water sample data (such as PH, TDS and water density, etc.) is read by the water physical index online monitoring device. Then close the second valve and open the third valve. The tested water sample flows into the sampling tube, is led out through the sampling tube and falls into the collection tube. The water sample in the collection tube is taken for conventional water chemical index, trace element, stable isotope and other tests;

[0020] Step 3: Grouting and testing, prepare cement slurry with a specific water-cement ratio (such as 3:1), introduce the cement slurry into the grouting bucket, and introduce the cement slurry into the rock tube through a mud pump until the predetermined pressure value is reached and then the first valve is closed. Then a series of time points (such as t1, t2, ... tn) are set, and the following operations are repeated at each time point: open the second valve to read the physical indicators of the water, then open the third valve, take samples and record the data, and close the first valve and the second valve after completion;

[0021] Step 4: Orthogonal test: conduct orthogonal tests with different water-cement ratios (3:1, 2:1, 1.5:1, 1:1) and different grouting pressures (such as 10MPa, 12MPa, 14MPa, 16MPa), repeat the above grouting and monitoring steps under each combination, and perform tests A1Bj to A4Bj (j=1, 2, 3, 4) according to the orthogonal experimental design chart, that is, for each water-cement ratio, conduct water release tests under different grouting pressures, monitor and analyze the changes in the physical properties and chemical composition of water;

[0022] Step 5: Data analysis: collect all test data, analyze the changes in groundwater quality before and after grouting, including differences in physical properties, chemical indicators, trace elements and isotopes, and study the specific effects of different water-cement ratios and grouting pressures on groundwater quality;

[0023] Step 6: Use different water quality ratios such as surface water, shallow groundwater, medium and deep groundwater, etc., prepare cement slurry according to the designed water-cement ratio, repeat the above consolidation and water release test, and analyze the law of different water qualities' effects on the water quality of the injected aquifer.

[0024] The present invention has the following advantages: 1. The present invention can systematically study and quantify the degree of disturbance of groundwater quality in the injected aquifer caused by slurry consolidation and water release with different slurrying and water distribution, and provide a scientific basis for evaluating and reducing the potential impact of coal mine grouting operations on the groundwater environment.

[0025] 2. The present invention can explore the optimal grouting formula and process parameters through orthogonal experimental design, such as combined experiments of A1 to A4 series (different water-cement ratios) and B1 to B4 grouting pressure levels, so as to minimize the negative impact on groundwater quality and provide scientific guidance for actual grouting operations.

[0026] 3. The present invention can take targeted measures to prevent or alleviate water quality deterioration by understanding the specific disturbance law of grouting on aquifer water quality, protect groundwater resources, especially those aquifers that serve as drinking water sources, and ensure drinking water safety for residents around mining areas.

[0027] 4. The present invention helps to balance the needs of coal mine water hazard prevention and control and groundwater environmental protection, reduce the risk of well flooding accidents, and improve the safety and sustainability of coal mining. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 It is a structural schematic diagram of the present invention.

[0029] Figure 2 It is a structural cross-sectional view of the present invention.

[0030] Figure 3 It is a three-dimensional structural cross-sectional view of the present invention.

[0031] Figure 4 Design diagram for orthogonal experiment of the present invention.

[0032] Figure numbers: 1_grouting barrel, 11_liquid inlet pipe, 12_liquid outlet pipe, 2_bracket, 21_mud pump, 22_liquid infusion pipe, 23_connecting pipe, 24_first valve, 25_sealing sleeve, 3_test bench, 31_servo motor, 32_bidirectional screw, 33_sliding seat, 34_rock tube, 35_injection hole plug, 4_cylinder, 41_sedimentation tube, 42_exhaust hole plug, 43_mud discharge hole plug, 44_water outlet pipe, 45_second valve, 5_casing, 51_online monitoring device for water physical indicators, 52_third valve, 53_sampling tube, 6_collecting tube, 7_control panel. DETAILED DESCRIPTION

[0033] The technical solution of the present invention is further described below in conjunction with the accompanying drawings.

[0034] A test device and method for grouting disturbance of groundwater quality, such as Figure 1-Figure 4 As shown, it includes a grouting bucket 1, a liquid inlet pipe 11, a liquid outlet pipe 12, a bracket 2, a test bench 3, a cylinder 4, a sedimentation cylinder 41, a water outlet pipe 44 and a sleeve 5. The upper right side of the grouting bucket 1 is connected to the liquid inlet pipe 11, the upper left side of the grouting bucket 1 is connected to the liquid outlet pipe 12, the left side of the grouting bucket 1 is provided with a bracket 2, the left side of the bracket 2 is provided with a test bench 3, the upper left sides of the front and rear parts of the test bench are both connected to the cylinder 4, the sedimentation cylinder 41 is connected between the telescopic ends of the cylinder 4, the lower left side of the sedimentation cylinder 41 is connected to the water outlet pipe 44, and the left part of the water outlet pipe 44 is slidably connected to the sleeve 5;

[0035] The bracket 2 includes a mud pump 21, a liquid infusion tube 22, a connecting tube 23, a first valve 24 and a sealing sleeve 25. The top of the bracket 2 is connected to the mud pump 21, the liquid infusion tube 22 is connected between the right side of the mud pump 21 and the liquid outlet tube 12, the left side of the mud pump 21 is connected to the connecting tube 23, the connecting tube 23 is provided with a first valve 24, and the left side of the connecting tube 23 is connected to the sealing sleeve 25;

[0036] The test bench 3 includes a servo motor 31, a bidirectional screw 32, a sliding seat 33, a rock tube 34 and a liquid injection hole plug 35. The right part of the test bench 3 is connected to the servo motor 31, and the bidirectional screw 32 is connected to the output shaft of the servo motor 31. The bidirectional screw 32 is rotatably connected to the test bench 3. The front and rear parts of the test bench 3 are both slidably connected to the sliding seats 33. The sliding seats 33 are both threadedly connected to the bidirectional screw 32. The tops of the sliding seats 33 are connected to the rock tubes 34. The liquid injection hole plugs 35 are arranged between the tops of the rock tubes 34. The left parts of the rock tubes 34 are in contact with the sealing sleeves 25, and the left parts of the rock tubes 34 are opened with liquid seepage holes.

[0037] The sedimentation cylinder 41 includes an air vent plug 42 and a mud discharge plug 43. The air vent plug 42 is provided at the top of the sedimentation cylinder 41, and the mud discharge plug 43 is provided at the bottom of the sedimentation cylinder 41.

[0038] The water outlet pipe 44 includes a second valve 45 ; the water outlet pipe 44 is provided with a second valve 45 ;

[0039] The casing 5 includes an online water physical index monitoring device 51, a third valve 52 and a sampling tube 53. The top of the casing 5 is connected to the online water physical index monitoring device 51, the left part of the casing 5 is provided with the third valve 52, and the left part of the third valve 52 is connected to the sampling tube 53;

[0040] It also includes a collecting tube 6, which is disposed on the lower left side of the sampling tube 53;

[0041] It also includes a control panel 7, and a control panel 7 is provided on the upper front side of the test bench 3;

[0042] When the present invention is used, a rubber film is first laid on the inner wall of the rock tube 34 and a specific rock block is placed therein. Then, the servo motor 31 controls the bidirectional screw rod 32, and the bidirectional screw rod 32 is used to control the rock tubes 34 to close each other to form a containing space. The rubber film blocks the gap between the inner walls of the rock tube 34 and can separate the subsequent cement slurry from the inside of the rock tube 34. Then, the mud discharge hole at the bottom of the sedimentation tube 41 is blocked by the mud discharge hole plug 43, while the exhaust hole and the injection hole are kept open, that is, the injection hole plug 35 and the exhaust hole plug 42 are removed, and the liquid is injected. Water is injected into the rock tube 34 through the hole (the water is taken from the groundwater of the injected aquifer on site) until the sedimentation tube 41 stops overflowing, and then the vent hole and the injection hole are blocked by the vent hole plug 42 and the injection hole plug 35. After that, the water in the rock tube 34 and the sedimentation tube 41 is left to stand for a week, and then the second valve 45 is opened, and the groundwater in the sedimentation tube 41 flows into the outlet pipe 44 and enters the casing 5 through the outlet pipe 44. The initial water sample data (such as PH, TDS and water density, etc.) is read by the water physical index online monitoring device 51, and then the second valve 45 is closed and the third valve 45 is opened. The water sample after the test flows into the sampling tube 53, and is led out through the sampling tube 53 and falls into the collecting tube 6. The water sample in the collecting tube 6 is taken for conventional water chemical index, trace element, stable isotope and other tests. Then the water is continued to be discharged. After the water level in the sedimentation tube 41 drops to the same elevation as the outlet pipe 44, it stops dropping. Then the second valve 45 and the third valve 52 are closed. Then the cement slurry is configured according to a specific water-cement ratio. The prepared cement slurry is introduced into the grouting bucket 1 through the liquid inlet pipe 11. Then the first valve 24 is opened to use the mud pump 2 1. The infusion pipe 22 and the connecting pipe 23 transport the cement slurry into the rock tube 34. When the grouting pressure reaches the preset value, the first valve 24 is closed, and then a series of time points (such as t1, t2, ... tn) are set. The consolidation degree of the cement slurry in different time periods is different, so the consolidation and water release state is also different. Therefore, it is necessary to repeat the following operations at each time point: open the second valve 45 to read the physical indicators of the water, then open the third valve 52, take samples and record the data, and after completion, close the first valve 24 and the second valve 45, and then conduct an orthogonal test, such as Figure 4As shown, tests A1Bj to A4Bj (j=1, 2, 3, 4) are performed, that is, for each water-cement ratio, water release tests are performed under different grouting pressures, the physical properties and chemical composition changes of water are monitored and analyzed, the test data are analyzed, and the influence of grouting on groundwater quality is studied. In order to ensure the accuracy of the test data, before each injection of cement slurry with different ratios, the inside of the sedimentation tube 41 and the rock tube 34 are cleaned. During cleaning, the servo motor 31 can control the bidirectional screw rod 32 to drive the rock tube 34 away from each other, and the mud discharge hole plug 43 can be pulled out to clean the sedimentation tube 41 and the inside of the rock, and if necessary, the rubber tube 34 needs to be cleaned. The skin film is replaced; the water for slurry preparation includes surface water, shallow groundwater, medium and deep groundwater, etc., and the cement slurry made with different water preparations and according to the designed water-cement ratio is subjected to a slurry consolidation and water release test, and its "test device" and "test method" are the same as above; through the test data analysis, the disturbance law of slurry consolidation and water release of cement slurry made with different water quality preparations on the water quality of groundwater in the injected aquifer is obtained. In summary, through the above-mentioned device and test operation steps of the present invention, the degree of disturbance of the water quality of groundwater in the injected aquifer by slurry consolidation and water release with different slurry preparations can be systematically studied and quantified, providing a scientific basis for evaluating and reducing the potential impact of coal mine grouting operations on the groundwater environment.

[0043] The above embodiments are provided for persons familiar with the art to implement or use the present invention. Personnel familiar with the art can make various modifications or changes to the above embodiments without departing from the inventive concept of the present invention. Therefore, the protection scope of the present invention is not limited to the above embodiments, but should be the maximum scope of the innovative features mentioned in the claims.

Claims

1. A test device for disturbing groundwater quality by grouting, comprising a grouting bucket (1), a liquid inlet pipe (11), a liquid outlet pipe (12), a bracket (2), a test bench (3), a cylinder (4), a sedimentation cylinder (41), a water outlet pipe (44) and a casing (5), wherein the upper right side of the grouting bucket (1) is connected to the liquid inlet pipe (11), and the upper left side of the grouting bucket (1) is connected to the liquid outlet pipe (12), wherein: A bracket (2) is arranged on the left side of the grouting barrel (1), a test bench (3) is arranged on the left side of the bracket (2), a cylinder (4) is connected to the upper left sides of both the front and rear parts of the test bench, a settling cylinder (41) is connected between the telescopic ends of the cylinder (4), a water outlet pipe (44) is connected to the left side of the lower part of the settling cylinder (41), and a sleeve (5) is slidably connected to the left part of the water outlet pipe (44).

2. A test device for disturbing groundwater quality by grouting according to claim 1, characterized in that: The support (2) comprises a mud pump (21), a liquid infusion pipe (22), a connecting pipe (23), a first valve (24) and a sealing sleeve (25); the top of the support (2) is connected to the mud pump (21); the liquid infusion pipe (22) is connected between the right side of the mud pump (21) and the liquid outlet pipe (12); the left side of the mud pump (21) is connected to the connecting pipe (23); the connecting pipe (23) is provided with a first valve (24); and the left side of the connecting pipe (23) is connected to the sealing sleeve (25).

3. A test device for disturbing groundwater quality by grouting according to claim 2, characterized in that: The test bench (3) comprises a servo motor (31), a bidirectional screw (32), a sliding seat (33), a rock tube (34) and a liquid injection hole plug (35). The right part of the test bench (3) is connected to the servo motor (31), the output shaft of the servo motor (31) is connected to the bidirectional screw (32), the bidirectional screw (32) is rotatably connected to the test bench (3), the front and rear parts of the test bench (3) are both slidably connected to the sliding seat (33), the sliding seat (33) is threadedly connected to the bidirectional screw (32), the top of the sliding seat (33) is connected to the rock tube (34), the top of the rock tube (34) is provided with a liquid injection hole plug (35), and the left part of the rock tube (34) is in contact with the sealing sleeve (25).

4. A test device for disturbing groundwater quality by grouting according to claim 3, characterized in that: The left part of the rock tube (34) is provided with seepage holes.

5. A test device for disturbing groundwater quality by grouting according to claim 4, characterized in that: The sedimentation cylinder (41) comprises an air vent plug (42) and a mud discharge plug (43); the top of the sedimentation cylinder (41) is provided with the air vent plug (42), and the bottom of the sedimentation cylinder (41) is provided with the mud discharge plug (43).

6. A test device for disturbing groundwater quality by grouting according to claim 5, characterized in that: The water outlet pipe (44) includes a second valve (45). The water outlet pipe (44) is provided with the second valve (45).

7. A test device and method for disturbing groundwater quality by grouting according to claim 6, characterized in that: The casing (5) comprises an online water physical index monitoring device (51), a third valve (52) and a sampling tube (53); the top of the casing (5) is connected to the online water physical index monitoring device (51); the left part of the casing (5) is provided with the third valve (52); and the left part of the third valve (52) is connected to the sampling tube (53).

8. A test device for disturbing groundwater quality by grouting according to claim 7, characterized in that: It also includes a collecting tube (6), which is arranged on the lower left side of the sampling tube (53).

9. A test device for disturbing groundwater quality by grouting according to claim 8, characterized in that: It also includes a control panel (7), and the control panel (7) is arranged on the front side of the upper part of the test bench (3).

10. A test method for grouting disturbance of groundwater quality according to any one of claims 1 to 9, characterized in that: The following steps are also included: Step 1: In the preparation stage, groundwater taken from the field is injected into the rock tube (34) at the injection hole plug (35) until the sedimentation tube (41) stops overflowing, and then the vent hole plug (42), mud discharge hole plug (43) and injection hole plug (35) are closed, and the groundwater in the rock tube (34) is allowed to stand for a week, thereby simulating a real groundwater environment; Step 2: Initial detection. Before the test, the second valve (45) is opened (half-opened), and the groundwater in the sedimentation cylinder (41) flows into the outlet pipe (44), and enters the casing (5) through the outlet pipe (44). The initial water sample data (such as pH, TDS and water density, etc.) is read by the water physical index online monitoring device (51). Then, the second valve (45) is closed and the third valve (52) is opened. The water sample after the test flows into the sampling tube (53), and is guided through the sampling tube (53) and falls into the collection cylinder (6). The water sample in the collection cylinder (6) is taken and tested for conventional water chemical indexes, trace elements, stable isotopes, etc.; Step 3: Grouting and testing, preparing cement slurry with a specific water-cement ratio (e.g., 3:1), introducing the cement slurry into a grouting bucket (1), and introducing the cement slurry into a rock tube (34) through a mud pump (21), until a predetermined pressure value is reached and then the first valve (24) is closed, and then a series of time points (e.g., t1, t2, ... tn) are set, and the following operations are repeated at each time point: opening the second valve (45) to read the physical index of the water, then opening the third valve (52), sampling and recording the data, and closing the first valve (24) and the second valve (45) after completion; Step 4: Orthogonal test: conduct orthogonal tests with different water-cement ratios (3:1, 2:1, 1.5:1, 1:1) and different grouting pressures (such as 10MPa, 12MPa, 14MPa, 16MPa), repeat the above grouting and monitoring steps under each combination, and perform tests A1Bj to A4Bj (j=1, 2, 3, 4) according to the orthogonal experimental design chart, that is, for each water-cement ratio, conduct water release tests under different grouting pressures, monitor and analyze the changes in the physical properties and chemical composition of water; Step 5: Data analysis: collect all test data, analyze the changes in groundwater quality before and after grouting, including differences in physical properties, chemical indicators, trace elements and isotopes, and study the specific effects of different water-cement ratios and grouting pressures on groundwater quality; Step 6: Use different water quality ratios such as surface water, shallow groundwater, medium and deep groundwater, etc., prepare cement slurry according to the designed water-cement ratio, repeat the above consolidation and water release test, and analyze the law of different water qualities' effects on the water quality of the injected aquifer.

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