Mine waste slurry reinjection treatment method

Abstract

The invention relates to the technical field of waste slurry treatment, in particular to a mine waste slurry reinjection treatment method. The method comprises the following steps that a mud pit is arranged, and the mud pit comprises a high-pollution mud pit and a low-pollution mud pit; a waste mud storage tank is arranged, an inlet of the waste mud storage tank is connected with the low-pollution mud pool, and an outlet pipeline of the waste mud storage tank is connected with the stirring pool; injecting the low-pollution waste slurry in the waste slurry storage tank into a stirring pool, and mixing the low-pollution waste slurry with cement in the stirring pool in proportion to obtain mixed slurry; cement grouting is adopted in the early stage of reinjection, after a stable grouting structure is formed, mixed grout is adopted for grouting, and in the later stage of grouting, the proportion of waste mud in the mixed grout is reduced till pure cement grouting is adopted, and grouting is completed. According to the mine waste mud reinjection treatment method, the waste mud treatment frequency and cost can be reduced, the grouting amount is increased, meanwhile, the waste mud is sealed in the underground stratum through grouting, ground pollution is reduced, and the ground use area is reduced.

Description

Technical Field

[0001] The invention relates to the technical field of waste mud treatment, and in particular to a method for reinjecting mining waste mud. Background Art

[0002] In the ground grouting area treatment project of mine water hazard, drilling and grouting operations are indispensable links; however, a large amount of waste mud will continue to be generated in this process. As the duration of drilling and grouting operations increases, the accumulation of waste mud shows a significant upward trend.

[0003] The current construction field faces many difficulties in dealing with these waste muds. First, conventional treatment methods often need to be carried out after the waste mud solidifies, which is not only time-consuming but also requires high treatment costs; second, the large amount of accumulated waste mud occupies a considerable area of ​​the construction site, seriously affecting the effective use of the construction site and the layout of the working space. With the continuous increase in the amount of waste mud, the originally limited site has been occupied in large quantities, interfering with the normal construction process and material stacking, equipment parking and other work; third, the waste mud itself is heavy, and the anti-leakage measures at the construction site are difficult to be foolproof. Under the long-term heavy pressure of waste mud and complex construction environment, there is still a risk of waste mud leakage.

[0004] Therefore, it is urgent to develop a method that can treat mine waste sludge efficiently, economically and environmentally friendly. Summary of the invention

[0005] The object of the present invention is to provide a method for reinjection treatment of waste mine mud, which can realize resource utilization of waste mud and minimize its harm to the environment and site occupation.

[0006] The present invention provides a method for reinjection treatment of mining waste sludge, comprising the following steps:

[0007] S1. Setting up a sludge pool, wherein the sludge pool includes a high-sludge pool and a low-sludge pool. After heavy metal ions are precipitated from the high-sludge pool, a low-sludge slurry is formed on the upper layer, and the low-sludge slurry is discharged into the low-sludge pool;

[0008] S2. A waste sludge storage tank is provided, wherein the inlet of the waste sludge storage tank is connected to the low-sludge sludge pool, and the outlet pipe of the waste sludge storage tank is connected to the mixing tank of the grouting station;

[0009] S3. The low-pollution waste sludge in the waste sludge storage tank is injected into the stirring tank, and the low-pollution waste sludge is mixed with the cement in the stirring tank in proportion to obtain a mixed slurry;

[0010] S4. Reinjection is performed. In the early stage of reinjection, cement grouting is used. After a stable grouting structure is formed, the mixed slurry obtained in step S3 is used for grouting. In the later stage of grouting, the proportion of low-pollution waste slurry in the mixed slurry is reduced until pure cement grouting is used to complete the grouting.

[0011] Preferably, in step S1, the volume of the high sludge tank is smaller than that of the low sludge tank.

[0012] Preferably, the inner walls of the high sludge tank and the low sludge tank in step S1 are both provided with an anti-corrosion and wear-resistant coating, and the anti-corrosion and wear-resistant coating is one of epoxy fiberglass coating, polyurea coating and vinyl resin coating.

[0013] Preferably, a stirring device is provided in the waste mud storage tank in step S2, and the stirring device stirs intermittently during the storage process.

[0014] Preferably, a flow regulating valve and a flow meter are provided between the waste mud storage tank and the stirring tank in step S2.

[0015] Preferably, the mass ratio between the low-pollution waste sludge and the cement in step S3 is (1-5):1000.

[0016] Preferably, when the low-pollutant waste sludge and the cement are mixed in step S3, stirring is started in the stirring tank, stirring at a low speed for 10-15 minutes, and then the stirring speed is increased for 15-20 minutes. Preferably, the low speed is 50-100 rpm, and the increased speed is 200-300 rpm.

[0017] Preferably, the specific parameters of grouting in step S4 are: grouting pressure is 4-10 MPa, and grouting flow rate is 20-40 cubic meters per minute.

[0018] Preferably, it also includes:

[0019] Step S5. Pre-treat the high-pollution sludge and the remaining low-pollution waste sludge from step S4 and then carry out centralized landfill treatment.

[0020] Preferably, the centralized landfill treatment adopts layered landfill, with each layer having a thickness of 30-50 cm and a compaction degree greater than 90%.

[0021] Beneficial effects:

[0022] The mine waste sludge reinjection treatment method provided by the present invention can reduce the frequency and cost of treating waste sludge, increase the grouting volume, and at the same time seal the waste sludge in the underground strata through grouting, thereby reducing ground pollution and reducing the ground use area.

[0023] The present invention can effectively classify and process waste mud and reduce pollution risks by zoning the mud pool; the reinjection process is stable and can effectively fill the pores of the formation and reinforce the formation. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0025] Figure 1 It is a schematic diagram of the structure of the present invention;

[0026] Figure 2 It is an underground schematic diagram during the reinjection process of the present invention;

[0027] Figure 3 This is a schematic diagram of the underground after reinjection and solidification according to the present invention.

[0028] 1-high sludge pool, 2-low sludge pool, 3-partition baffle, 4-waste sludge storage tank, 5-mixing tank, 6-plastic pipe. DETAILED DESCRIPTION

[0029] It should be noted that the following detailed descriptions are illustrative and are intended to provide further explanation of the present application. Unless otherwise specified, all technical and scientific terms used herein have the same meanings as those commonly understood by those skilled in the art to which the present application belongs.

[0030] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form also includes the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this description, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0031] The technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0032] Example 1

[0033] A method for reinjecting waste sludge from a mine, comprising the following steps:

[0034] S1. Set up a mud pool, such as Figure 1 As shown, the sludge pool includes a high-sludge pool 1 and a low-sludge pool 2; the volume of the high-sludge pool 1 is smaller than that of the low-sludge pool 2, a partition baffle 3 is provided between the high-sludge pool 1 and the low-sludge pool 2, and the inner walls of the high-sludge pool 1 and the low-sludge pool 2 are both provided with epoxy glass fiber reinforced plastic anti-corrosion and wear-resistant coatings;

[0035] The slurry without adding heavy metal ions and polluting materials can be directly discharged into the low-pollution slurry pool 2, while the slurry with adding other highly polluting materials such as barite is discharged into the high-pollution slurry pool 1. After the high-pollution slurry in the high-pollution slurry pool 1 precipitates heavy metal ions by sedimentation method, pH value and other methods, a low-pollution slurry is formed on the upper layer. After the heavy metal ion concentration is tested to meet the requirements, the low-pollution slurry is discharged into the low-pollution slurry pool 2;

[0036] S2. A waste mud storage tank 4 is provided, and a stirring device is provided in the waste mud storage tank 4. During the storage process, the stirring device stirs the waste mud intermittently to prevent the waste mud from settling and stratifying, thereby ensuring its uniformity and fluidity; the inlet of the waste mud storage tank 4 is connected to the low-sludge slurry pool 2, and the outlet of the waste mud storage tank 4 is connected to the stirring pool 5 of the grouting station through a plastic pipe 6. A flow regulating valve and a flow meter are provided between the waste mud storage tank 4 and the stirring pool 5;

[0037] S3. The low-pollution waste sludge in the waste sludge storage tank 4 is injected into the stirring tank 5, and the low-pollution waste sludge is mixed with the cement in the stirring tank 5 at a mass ratio of 3:1000, and the stirring speed in the stirring tank 5 is low-speed stirred at 80 rpm for 13 minutes, and then the stirring speed is increased to 260 rpm and stirred for 18 minutes to obtain a mixed slurry;

[0038] S4. Reinjection is performed. Cement grouting is used in the early stage of reinjection. After effectively filling the pores of the formation and forming a stable grouting structure, the mixed slurry obtained in step S3 is used for grouting. In the later stage of grouting, the proportion of low-pollution waste slurry in the mixed slurry is reduced until pure cement grouting is used. During the grouting process, the grouting pressure is 8MPa, the grouting flow rate is 30 cubic meters / minute, and the grouting is completed;

[0039] Step S5. After a small amount of high-pollutant waste sludge and the remaining low-pollutant waste sludge in step S4 are pre-treated (sedimentation separation dehydration and solidification treatment), they are centrally landfilled. The centralized landfill treatment adopts layered landfilling, each layer is 40 cm thick and has a compaction degree of 95%, which can prevent the leakage of harmful substances and reduce pollution to the soil and groundwater.

[0040] The pre-treatment process can be carried out by the local waste disposal department.

[0041] Example 2

[0042] A method for reinjecting waste sludge from a mine, comprising the following steps:

[0043] S1. A sludge pool is set up, and the sludge pool includes a high-sludge pool 1 and a low-sludge pool 2; the volume of the high-sludge pool 1 is smaller than that of the low-sludge pool 2, a partition baffle 3 is provided between the high-sludge pool 1 and the low-sludge pool 2, and the inner walls of the high-sludge pool 1 and the low-sludge pool 2 are both provided with a polyurea anti-corrosion and wear-resistant coating;

[0044] The slurry without adding heavy metal ions and polluting materials can be directly discharged into the low-pollution slurry pool 2, while the slurry with adding other highly polluting materials such as barite is discharged into the high-pollution slurry pool 1. After the high-pollution slurry in the high-pollution slurry pool 1 precipitates heavy metal ions by sedimentation method, pH value and other methods, a low-pollution slurry is formed on the upper layer. After the heavy metal ion concentration is tested to meet the requirements, the low-pollution slurry is discharged into the low-pollution slurry pool 2;

[0045] S2. A waste mud storage tank 4 is provided, and a stirring device is provided in the waste mud storage tank 4. During the storage process, the stirring device stirs the waste mud intermittently to prevent the waste mud from settling and stratifying, thereby ensuring its uniformity and fluidity; the inlet of the waste mud storage tank 4 is connected to the low-sludge slurry pool 2, and the outlet of the waste mud storage tank 4 is connected to the stirring pool 5 of the grouting station through a plastic pipe 6. A flow regulating valve and a flow meter are provided between the waste mud storage tank 4 and the stirring pool 5;

[0046] S3. The low-pollution waste sludge in the waste sludge storage tank 4 is injected into the stirring tank 5, and the low-pollution waste sludge is mixed with the cement in the stirring tank 5 at a mass ratio of 1:1000, and the stirring speed in the stirring tank 5 is low-speed stirred at 50 rpm for 15 minutes, and then the stirring speed is increased to 300 rpm and stirred for 15 minutes to obtain a mixed slurry;

[0047] S4. Reinjection is performed. Cement grouting is used in the early stage of reinjection. After a stable grouting structure is formed, the mixed slurry obtained in step S3 is used for grouting. In the later stage of grouting, the proportion of low-pollution waste slurry in the mixed slurry is reduced until pure cement grouting is used. During the grouting process, the grouting pressure is 4MPa, the grouting flow rate is 20 cubic meters / minute, and the grouting is completed;

[0048] Step S5. Pre-treat a small amount of high-pollution sludge and the remaining low-pollution waste sludge from step S4 (sedimentation separation, dehydration and solidification treatment) and then carry out centralized landfill treatment. The centralized landfill treatment adopts layered landfill, each layer has a landfill thickness of 30 cm and a compaction degree of 92%.

[0049] The pre-treatment process can be carried out by the local waste disposal department.

[0050] Example 3

[0051] A method for reinjecting waste sludge from a mine, comprising the following steps:

[0052] S1. Set up a sludge pool, which includes a high-sludge pool 1 and a low-sludge pool 2; the volume of the high-sludge pool 1 is smaller than that of the low-sludge pool 2, and a partition baffle 3 is provided between the high-sludge pool 1 and the low-sludge pool 2. The inner walls of the high-sludge pool 1 and the low-sludge pool 2 are both provided with an anti-corrosion and wear-resistant coating, and the anti-corrosion and wear-resistant coating adopts one of epoxy fiberglass coating, polyurea coating and vinyl resin coating.

[0053] The slurry without adding heavy metal ions and polluting materials can be directly discharged into the low-pollution slurry pool 2, while the slurry with adding other highly polluting materials such as barite is discharged into the high-pollution slurry pool 1. After the high-pollution slurry in the high-pollution slurry pool 1 precipitates heavy metal ions by sedimentation method, pH value and other methods, a low-pollution slurry is formed on the upper layer. After the heavy metal ion concentration is tested to meet the requirements, the low-pollution slurry is discharged into the low-pollution slurry pool 2;

[0054] S2. A waste mud storage tank 4 is provided, and a stirring device is provided in the waste mud storage tank 4. During the storage process, the stirring device stirs the waste mud intermittently to prevent the waste mud from settling and stratifying, thereby ensuring its uniformity and fluidity; the inlet of the waste mud storage tank 4 is connected to the low-sludge slurry pool 2, and the outlet of the waste mud storage tank 4 is connected to the stirring pool 5 of the grouting station through a plastic pipe 6. A flow regulating valve and a flow meter are provided between the waste mud storage tank 4 and the stirring pool 5;

[0055] S3. The low-pollution waste sludge in the waste sludge storage tank 4 is injected into the stirring tank 5, and the low-pollution waste sludge is mixed with the cement in the stirring tank 5 at a mass ratio of 5:1000, and the stirring speed in the stirring tank 5 is low-speed stirred at 100 rpm for 10 minutes, and then the stirring speed is increased to 200 rpm and stirred for 20 minutes to obtain a mixed slurry;

[0056] S4. Reinjection is performed. Cement grouting is used in the early stage of reinjection. After a stable grouting structure is formed, the mixed slurry obtained in step S3 is used for grouting. In the later stage of grouting, the proportion of low-pollution waste slurry in the mixed slurry is reduced until pure cement grouting is used. During the grouting process, the grouting pressure is 10MPa, the grouting flow rate is 40 cubic meters / minute, and the grouting is completed;

[0057] Step S5. Pre-treat a small amount of high-pollution waste sludge and the remaining low-pollution waste sludge in step S4 (sedimentation separation, dehydration and solidification treatment) and then carry out centralized landfill treatment. The centralized landfill treatment adopts layered landfill, each layer of which is 50 cm thick and has a compaction degree greater than 96%.

[0058] The pre-treatment process can be carried out by the local waste disposal department.

[0059] The underground schematic diagram during the reinjection process of the present invention is as follows Figure 2As shown, it can be seen that the mixed slurry starts from the surface injection point and diffuses underground along a specific path, which shows that the moderate slurry of low-pollution waste mud and cement can be effectively injected into the specific underground stratum according to the above-mentioned mixing ratio, ensuring that the mixed slurry is evenly distributed underground. At the same time, the diffusion path of the mixed slurry underground shows that this reinjection method can fill the gaps in the stratum, play a role in strengthening the stratum, and prevent geological problems such as stratum collapse.

[0060] Schematic diagram of underground after grouting solidification Figure 3 As shown, it can be seen that over time, the mixed slurry gradually changes from the initial liquid state to a solid state, and a stable structure is formed underground. It can be seen from the figure that the mixed slurry of low-pollution waste mud and cement can be successfully solidified underground. The solidification process of cement can effectively fix the low-pollution waste mud underground to prevent it from flowing or seeping out again, achieving the purpose of long-term treatment of low-pollution waste mud; the formed solidified structure can enhance the stability of the formation, which is of great significance for the repair and reinforcement of the formation after mining, and also solves the problem of environmental protection treatment of waste mud.

[0061] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for reinjection treatment of mining waste sludge, characterized in that: The following steps are involved: S1. Setting a sludge pool, wherein the sludge pool includes a high-sludge pool and a low-sludge pool, wherein after the high-sludge sludge in the high-sludge pool is precipitated, a low-sludge slurry is formed on the upper layer, and the low-sludge slurry is discharged into the low-sludge pool; S2. A waste sludge storage tank is provided, wherein the inlet of the waste sludge storage tank is connected to the low-sludge sludge pool, and the outlet pipe of the waste sludge storage tank is connected to the mixing tank of the grouting station; S3. The low-pollution waste sludge in the waste sludge storage tank is injected into the stirring tank, and the low-pollution waste sludge is mixed with the cement in the stirring tank in proportion to obtain a mixed slurry; S4. Reinjection is performed. In the early stage of reinjection, cement grouting is used. After a stable grouting structure is formed, the mixed slurry obtained in step S3 is used for grouting. In the later stage of grouting, the proportion of low-pollution waste slurry in the mixed slurry is reduced until pure cement grouting is used to complete the grouting.

2. The method for reinjection treatment of mining waste sludge according to claim 1, characterized in that: In the step S1, the volume of the high sludge tank is smaller than that of the low sludge tank.

3. The method for reinjection treatment of mining waste sludge according to claim 1, characterized in that: In the step S1, the inner walls of the high sludge tank and the low sludge tank are both provided with an anti-corrosion and wear-resistant coating, and the anti-corrosion and wear-resistant coating is one of epoxy fiberglass coating, polyurea coating and vinyl resin coating.

4. The method for reinjection treatment of mining waste sludge according to claim 1, characterized in that: In the step S2, a stirring device is provided in the waste mud storage tank, and the stirring device stirs intermittently during the storage process.

5. The method for reinjection treatment of mining waste sludge according to claim 1, characterized in that: In the step S2, a flow regulating valve and a flow meter are provided between the waste mud storage tank and the stirring tank.

6. The method for reinjection treatment of mining waste sludge according to claim 1, characterized in that: The mass ratio between the low-pollution waste sludge and the cement in step S3 is (1-5):1000.

7. The method for reinjection treatment of mining waste sludge according to claim 1, characterized in that: When the low-pollution waste sludge and the cement are mixed in step S3, stirring is started in the stirring tank, and stirring is carried out at a low speed for 10-15 minutes, and then the stirring speed is increased and stirred for 15-20 minutes.

8. The method for reinjection treatment of mining waste sludge according to claim 1, characterized in that: The specific parameters of the grouting in step S4 are as follows: the grouting pressure is 4-10 MPa, and the grouting flow rate is 20-40 cubic meters per minute.

9. The method for reinjection treatment of mining waste sludge according to claim 1, characterized in that: Also includes: Step S5. Pre-treat the high-pollution waste sludge and the remaining low-pollution waste sludge from step S4 and then carry out centralized landfill treatment.

10. The method for reinjection treatment of mining waste sludge according to claim 9, characterized in that: The centralized landfill treatment adopts layered landfill, each layer has a landfill thickness of 30-50 cm and a compaction degree of more than 90%.

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