A river sludge in-situ solidification treatment process

Abstract

The present invention discloses an in-situ solidification treatment process for river sludge, which specifically includes the following steps: S1, draining the surface water in the river channel to expose the sludge at the bottom of the river channel; S2, dividing the riverbed sludge into multiple partitions according to the properties of the sludge; S3, sampling the sludge in each partition, measuring the moisture content of each sludge sample to obtain the moisture content of the sludge in the corresponding partition; S4, designing the optimal moisture content of the sludge, and pre-treating the sludge in each partition; S5, designing the mix ratio of sludge and curing agent, and curing the sludge based on the designed mix ratio; S6, curing the solidified sludge, and using it as a construction access road after curing is completed and rolled and leveled. The present invention performs partition treatment on the sludge according to the properties of the sludge, so that the sludge in each partition reaches the optimal moisture content. When the sludge is solidified by a stirring device, the curing agent in the high moisture content area can be prevented from penetrating and diffusing to the surrounding area, which affects the sludge solidification effect.

Description

Technical Field

[0001] The present invention relates to the technical field of sludge solidification, and more specifically, to an in-situ solidification treatment process for river sludge. Background Art

[0002] River silt is stored at the bottom of the river. Pollutants are enriched in the silt. When the external environment is changed, the pollutants are likely to be released again, acting as an internal pollution source and affecting the water function of the river. Therefore, the silt needs to be solidified to prevent pollutants from polluting the surrounding environment. Since most of the two sides of the river are basic farmland, there are no environmental and spatial conditions for the construction of temporary construction roads, and the on-site relocation is difficult and the relocation cycle is long, so the in-situ solidification treatment method is often used.

[0003] In-situ solidification treatment technology is to use solidification materials to stir the silt in-situ to make the soil reach a certain strength. During in-situ mixing, the solidification slurry delivered by the background feeding system is often mixed evenly into the silt through the mixing equipment. However, the silt moisture content in different areas of the riverbed is different. For areas with higher moisture content, when the mixing equipment is performing solidification work, the solidification slurry is sprayed into the silt with the mixing equipment. The solidification slurry is easy to seep outward with the water in the silt, affecting the silt solidification effect at the mixing point. Summary of the invention

[0004] Another object of the present invention is to provide an in-situ solidification treatment process for river sludge that ensures the solidification effect.

[0005] In order to achieve these purposes and other advantages according to the present invention, a river sludge in-situ solidification treatment process is provided, which specifically comprises the following steps:

[0006] S1. Pump out the surface water in the river until the silt at the bottom of the river is exposed; clean the silt in the river and let the silt at the bottom of the river dry naturally;

[0007] S2. Survey the riverbed silt and divide the riverbed silt into multiple zones according to the properties of the silt;

[0008] S3, sampling the sludge in each partition, sieving the sludge to retain the sludge with a particle size of less than 40 mm as the sludge sample, and measuring the moisture content of each sludge sample to obtain the moisture content of the sludge in the corresponding partition;

[0009] S4. Design the optimal moisture content of sludge, pre-treat the sludge in each partition, and make the moisture content of the sludge in each partition reach the optimal moisture content;

[0010] S5. Designing a mix ratio of sludge and curing agent, determining the amount of curing agent required for curing the sludge in each partition based on the designed mix ratio, and stirring the sludge and curing agent by a stirring device to cure the sludge;

[0011] S6. The cured and solidified silt can be used as a construction access road after being rolled and leveled.

[0012] Preferably, the process of measuring the moisture content of sludge in step S3 is:

[0013] S31, selecting a plurality of sampling points in each partition;

[0014] S32, vertically insert the sampling device into one of the sampling points until it cannot be inserted further manually, mark the insertion depth, pull out the sampling device, take out the sludge in the sampling device, crush and screen it, and then test the moisture content; repeat the above steps to complete the sampling of other sampling points, and record the insertion depth and moisture content of each sampling point;

[0015] S33, taking the average value of the insertion depth of each sampling point as the sludge depth of the partition; taking the average value of the sludge moisture content of each sampling point as the sludge moisture content of the partition.

[0016] Preferably, the process of pre-treating the sludge in step S4 is: for sludge with a moisture content above the optimum moisture content, quicklime is added and the sludge and quicklime are stirred by a stirring device to reduce the moisture content of the sludge to the optimum moisture content; for sludge with a moisture content below the optimum moisture content, water is added and the sludge and water are stirred by a stirring device to make the moisture content of the sludge reach the optimum moisture content.

[0017] Preferably, in step S5, the curing agent is composed of a liquid curing agent and cement, and the curing treatment of the sludge specifically comprises the following steps:

[0018] S51, based on the mix ratio of sludge and curing agent, and according to the sludge depth of each partition calculated in step S33, calculate the amount of cement and the amount of liquid curing agent required per cubic meter of sludge in each partition;

[0019] S52, evenly spreading cement on the sludge surface in each partition; selecting a stirring point in each partition, stirring the sludge and cement at the stirring point by a stirring device, and spraying a liquid curing agent to the stirring point while stirring to solidify the sludge.

[0020] Preferably, the mixing ratio of sludge to curing agent is: sludge: cement: liquid curing agent = 1-2: 9-12: 0.020-0.026; the optimal moisture content of the sludge is 45%.

[0021] Preferably, the stirring device comprises:

[0022] A mixer, which is provided with two mixing heads and an ash delivery pipe, wherein the output end of the ash delivery pipe is located between the two mixing heads;

[0023] A mobile feed bin is connected to the input end of the ash delivery pipe through a hose, and the output end of the ash delivery pipe is connected to a spray gun. The mobile feed bin pumps liquid curing agent into the ash delivery pipe, and sprays the liquid curing agent into the sludge to be solidified through the spray gun;

[0024] Two sets of cutting devices are respectively arranged on the two stirring heads and are used for cutting sludge.

[0025] Preferably, any group of cutting devices comprises a plurality of cutting device units, which are arranged circumferentially and spaced apart along the outer side wall of the corresponding stirring head, and any cutting device unit comprises:

[0026] Two shaft plates are arranged between two adjacent blades of the mixing head, and any shaft plate is rotatably connected to the side wall of the corresponding blade;

[0027] The cutting cylinder is arranged between the two shaft plates, and the cutting cylinder includes a plurality of coaxially arranged cutting units with gradually decreasing diameters. Each cutting unit is formed by a plurality of elastic steel wire ropes, and the two ends of each steel wire rope are respectively fixedly connected to the two shaft plates, and the elastic steel wire ropes on the plurality of cutting units are arranged at intervals and staggered.

[0028] The present invention includes at least the following beneficial effects: the present invention performs zoned treatment on the sludge according to the properties of the sludge, so that the sludge in each zone reaches the optimal moisture content. When the sludge is solidified by a stirring device, the curing agent in the high moisture content area can be prevented from penetrating and diffusing to the surrounding area, thereby affecting the sludge solidification effect. At the same time, since the moisture content of the sludge in each zone is the same after pretreatment, the same concentration of curing agent can be used when the sludge is solidified. There is no need to prepare curing agent solutions of different concentrations according to the different moisture contents of the sludge to ensure the solidification effect, thereby reducing the construction difficulty.

[0029] Other advantages, objectives and features of the present invention will be embodied in part through the following description, and in part will be understood by those skilled in the art through study and practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 It is a structural schematic diagram of the stirring device of the present invention;

[0031] Figure 2 It is a structural schematic diagram of the stirring head of the present invention;

[0032] Figure 3 It is a structural schematic diagram of the cutting unit of the present invention;

[0033] Description of the drawings:

[0034] 1. Mixer, 101. Mixing head, 102. Ash delivery pipe, 103. Blade, 2. Mobile feeding bin, 201. Hose, 3. Spray gun, 4. Cutting device unit, 401. Shaft plate, 402. Cutting unit, 403. Elastic steel wire rope. DETAILED DESCRIPTION

[0035] The present invention is further described in detail below in conjunction with the accompanying drawings so that those skilled in the art can implement the invention with reference to the description.

[0036] It should be noted that, in the description of the present invention, the terms "lateral", "longitudinal", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside" and "outside" etc. indicating orientations or positional relationships are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0037] like Figure 1-3 As shown, the present invention provides a river sludge in-situ solidification treatment process, which specifically includes the following steps:

[0038] S1. Pump out the surface water in the river until the mud at the bottom of the river is exposed; clean up the mud in the river, remove the trees, domestic garbage, and construction waste on the river slopes, remove the reed roots, weeds, construction waste, and gravel in the mud, and let the mud at the bottom of the river dry naturally for 1 to 2 days;

[0039] S2. Survey the riverbed silt and divide the riverbed silt into multiple zones according to the properties of the silt;

[0040] S3, sampling the sludge in each partition, sieving the sludge to retain the sludge with a particle size of less than 40 mm as the sludge sample, and measuring the moisture content of each sludge sample to obtain the moisture content of the sludge in the corresponding partition;

[0041] S4. Design the optimal moisture content of sludge, pre-treat the sludge in each partition, and make the moisture content of the sludge in each partition reach the optimal moisture content;

[0042] The process of sludge pretreatment is as follows: for sludge with a moisture content above the optimum moisture content, quicklime is added and the sludge and quicklime are stirred by a stirring device to reduce the moisture content of the sludge to the optimum moisture content; for sludge with a moisture content below the optimum moisture content, water is added and the sludge and water are stirred by a stirring device to make the moisture content of the sludge reach the optimum moisture content;

[0043] S5. Designing a mix ratio of sludge and curing agent, determining the amount of curing agent required for curing the sludge in each partition based on the designed mix ratio, and stirring the sludge and curing agent by a stirring device to cure the sludge;

[0044] S6. The cured and solidified silt can be used as a construction access road after being rolled and leveled.

[0045] In the above technical scheme, the present invention performs zoned treatment on the sludge according to the properties of the sludge, so that the sludge in each zone reaches the optimal moisture content. When the sludge is solidified by a stirring device, the curing agent in the high moisture content area can be prevented from penetrating and diffusing to the surrounding area, thereby affecting the sludge solidification effect. At the same time, since the moisture content of the sludge in each zone is the same after pretreatment, the same concentration of curing agent can be used when the sludge is solidified. There is no need to prepare curing agent solutions of different concentrations according to the different moisture contents of the sludge to ensure the solidification effect, thereby reducing the construction difficulty.

[0046] In another technical solution, the process of measuring the sludge moisture content in step S3 is as follows:

[0047] S31, selecting a plurality of sampling points in each partition;

[0048] S32, vertically insert the sampling device into one of the sampling points until it cannot be inserted further manually, mark the insertion depth, pull out the sampling device, take out the sludge in the sampling device, crush and screen it, and then test the moisture content; repeat the above steps to complete the sampling of other sampling points, and record the insertion depth and moisture content of each sampling point;

[0049] S33, taking the average value of the insertion depth of each sampling point as the sludge depth of the partition; taking the average value of the sludge moisture content of each sampling point as the sludge moisture content of the partition.

[0050] In the present technical solution, multiple sampling points are selected on each partition, and the average value of the moisture content of the multiple sampling points is taken as the moisture content of the corresponding partition, which can improve the detection accuracy of the moisture content of the partition; and the insertion depth is recorded during the sampling process to obtain the sludge depth of each partition, which can provide a data source for the subsequent calculation of the amount of curing agent required for the solidification of the sludge in each partition.

[0051] In another technical solution, in step S5, the curing agent is composed of a liquid curing agent and cement, and the curing treatment of the sludge specifically includes the following steps:

[0052] S51, based on the mix ratio of sludge and curing agent, and according to the sludge depth of each partition calculated in step S33, calculate the amount of cement and the amount of liquid curing agent required per cubic meter of sludge in each partition;

[0053] S52, evenly spreading cement on the sludge surface in each partition; selecting a stirring point in each partition, stirring the sludge and cement at the stirring point by a stirring device, and spraying a liquid curing agent to the stirring point while stirring to solidify the sludge.

[0054] In the present technical scheme, the curing agent is composed of a liquid curing agent and cement. The combination of cement and liquid curing agent can act on the silt to improve the curing strength of the silt, so that after the silt is solidified and rolled flat, it can be directly used as a temporary road without drying, which provides convenience for the subsequent equipment to enter the site and also improves work efficiency. When the silt is solidified, the amount of curing agent required is calculated by zone to ensure calculation accuracy and avoid waste of resources. The zoned stirring can ensure the adequacy of the mixing of the silt and the curing agent and ensure the curing effect of the silt.

[0055] In another technical solution, the mixing ratio of sludge to curing agent is: sludge: cement: liquid curing agent = 1-2: 9-12: 0.020-0.026; the optimal moisture content of the sludge is 45%.

[0056] In the present technical scheme, the mixing ratio of silt and curing agent is preferably silt: cement: liquid curing agent = 1:10:0.022; limiting the mixing ratio of silt and curing agent and the optimal moisture content can ensure the curing strength of the silt while saving material costs; by using the ratio of curing agent and silt of the present invention to solidify the silt, the solidified silt only needs to be cured for 24 hours, which greatly shortens the curing time.

[0057] In another technical solution, the stirring device includes:

[0058] A mixer 1 is provided with two mixing heads 101 and an ash delivery pipe 102, wherein the output end of the ash delivery pipe 102 is located between the two mixing heads 101;

[0059] A mobile feed bin 2 is connected to the input end of the ash delivery pipe 102 through a hose 201, and the output end of the ash delivery pipe 102 is connected to a spray gun 3. The mobile feed bin 2 pumps liquid curing agent into the ash delivery pipe 102, and sprays the liquid curing agent into the sludge to be cured through the spray gun 3;

[0060] Two sets of cutting devices are respectively arranged on the two stirring heads 101 for cutting sludge.

[0061] In the technical solution, the model of the mixer 1 is GH-3000 / GH-5000, and the mixer is provided with an ash delivery pipe 102 and two stirring heads 101. The output end of the ash delivery pipe is located between the two stirring heads 101, and is used to inject the liquid curing agent into the sludge. The two stirring heads rotate to stir the sludge and the liquid curing agent. The present invention provides a spray gun 3 at the output end of the ash delivery pipe 102, and sprays the liquid curing agent into the sludge to be solidified through the spray gun 3. Compared with directly injecting the liquid curing agent into the sludge through the ash delivery pipe 102, the liquid curing agent is released by spraying, and the liquid curing agent is dispersed in a wider range and more effectively. Uniform, better solidification effect; cutting devices are provided on the two stirring heads 101. When the sludge and the solidifying agent are mixed by the stirring head 101, the cutting devices rotate along with the stirring head 101 to cut large agglomerates of sludge, so as to avoid excessive large agglomerates of sludge affecting the uniformity of mixing the sludge and the liquid solidifying agent, thereby ensuring the solidification effect; and before the sludge is solidified, a stirring device is also used to pre-treat the sludge. During the pre-treatment process, the cutting device is also used to cut large agglomerates of sludge. Through multiple cutting, the cutting effect of large agglomerates of sludge is ensured, and the uniformity of subsequent mixing of the sludge and the liquid solidifying agent is ensured.

[0062] In another technical solution, any group of cutting devices includes a plurality of cutting device units 4, which are arranged circumferentially and spaced apart along the outer side wall of the corresponding stirring head 101, and any cutting device unit 4 includes:

[0063] Two shaft plates 401 are arranged between two adjacent blades 103 of the stirring head 101, and any shaft plate 401 is rotatably connected to the side wall of the corresponding blade wing 103;

[0064] The cutting cylinder is arranged between the two shaft plates 401, and the cutting cylinder includes a plurality of coaxially arranged cutting units 402 with gradually decreasing diameters. Any cutting unit 402 is formed by surrounding a plurality of elastic steel wire ropes 403, and the two ends of any steel wire rope are respectively fixedly connected to the two shaft plates 401, and the elastic steel wire ropes 403 on the plurality of cutting units 402 are arranged at intervals and staggered.

[0065] In the present technical solution, a plurality of cutting device units 4 are arranged on the outer wall of any mixing head, and the plurality of cutting device units 4 are located between the plurality of blades of the mixing head. The two ends of any cutting device unit are connected to the two blades located at the two ends thereof through an axis plate. The cutting cylinder comprises a plurality of coaxially arranged cutting units 402 with gradually decreasing diameters. Any cutting unit 402 is surrounded by a plurality of elastic steel wire ropes 403 to form a cylindrical structure. When the mixing head 101 rotates, the cutting unit 402 rotates with the mixing head 101 and cuts the large aggregate silt through the steel wire rope. Since there are uncleaned gravels in the silt, the steel wire rope may cut the gravels when cutting the silt. In order to avoid hard contact between the steel wire rope and the gravel and thus cut the steel wire rope, the steel wire rope adopts an elastic steel wire rope 403. When the cutting unit 402 cuts the gravel, the gravel will squeeze into the cutting unit from the gap between the adjacent steel wire ropes. The cutting unit 402 is arranged coaxially and the steel wire ropes on the cutting units 402 are arranged at intervals and staggered from each other, which can ensure the cutting strength and elastic deformation ability of the cutting cylinder; the cutting cylinder is rotatably connected to the blade wing 103 of the mixing head 101 through the shaft plate 401, so that when the mixing head 101 rotates, the cutting cylinder can also rotate around its own axis under the force of silt or gravel. When the cutting cylinder cuts the gravel, the rotating setting can play a buffering role for the cutting cylinder, further extending the service life of the cutting cylinder; a pin can be welded on the blade wing 103, and a pin hole is opened in the middle of the shaft plate 401. The shaft plate 401 is rotatably connected to the pin through the pin hole to achieve a rotatable connection with the blade wing 103.

[0066] Although the embodiments of the present invention have been disclosed as above, they are not limited to the applications listed in the specification and the implementation modes, and they can be fully applied to various fields suitable for the present invention. For those familiar with the art, additional modifications can be easily implemented. Therefore, without departing from the general concept defined by the claims and the scope of equivalents, the present invention is not limited to the specific details and the illustrations shown and described herein.

Claims

1. A process for in-situ solidification treatment of river sludge, characterized in that: The specific steps include: S1. Pump out the surface water in the river until the silt at the bottom of the river is exposed; clean the silt in the river and let the silt at the bottom of the river dry naturally; S2. Survey the riverbed silt and divide the riverbed silt into multiple zones according to the properties of the silt; S3, sampling the sludge in each partition, sieving the sludge to retain the sludge with a particle size of less than 40 mm as the sludge sample, and measuring the moisture content of each sludge sample to obtain the moisture content of the sludge in the corresponding partition; S4. Design the optimal moisture content of sludge, pre-treat the sludge in each partition, and make the moisture content of the sludge in each partition reach the optimal moisture content; S5. Designing a mix ratio of sludge and curing agent, determining the amount of curing agent required for curing the sludge in each partition based on the designed mix ratio, and stirring the sludge and curing agent by a stirring device to cure the sludge; S6. The silt after curing and solidification is used as a construction access road after curing and rolling; The stirring device comprises two groups of cutting devices, which are respectively arranged on two stirring heads for cutting sludge. Each group of cutting devices comprises a plurality of cutting device units, which are arranged at intervals along the outer side wall of the corresponding stirring head. Each cutting device unit comprises: Two shaft plates are arranged between two adjacent blades of the mixing head, and any shaft plate is rotatably connected to the side wall of the corresponding blade; The cutting cylinder is arranged between the two shaft plates, and the cutting cylinder includes a plurality of coaxially arranged cutting units with gradually decreasing diameters. Each cutting unit is formed by a plurality of elastic steel wire ropes, and the two ends of each steel wire rope are respectively fixedly connected to the two shaft plates, and the elastic steel wire ropes on the plurality of cutting units are arranged at intervals and staggered.

2. The in-situ solidification treatment process for river sludge according to claim 1, characterized in that: The process of measuring the moisture content of sludge in step S3 is as follows: S31, selecting a plurality of sampling points in each partition; S32, vertically insert the sampling device into one of the sampling points until it cannot be inserted further manually, mark the insertion depth, pull out the sampling device, take out the sludge in the sampling device, crush and screen it, and then test the moisture content; repeat the above steps to complete the sampling of other sampling points, and record the insertion depth and moisture content of each sampling point; S33, taking the average value of the insertion depth of each sampling point as the sludge depth of the partition; taking the average value of the sludge moisture content of each sampling point as the sludge moisture content of the partition.

3. The in-situ solidification treatment process for river sludge according to claim 1, characterized in that: The process of pre-treating the sludge in step S4 is as follows: for sludge with a moisture content above the optimum moisture content, quicklime is added and the sludge and quicklime are stirred by a stirring device to reduce the moisture content of the sludge to the optimum moisture content; for sludge with a moisture content below the optimum moisture content, water is added and the sludge and water are stirred by a stirring device to make the moisture content of the sludge reach the optimum moisture content.

4. The in-situ solidification treatment process for river sludge according to claim 2, characterized in that: In step S5, the curing agent is composed of a liquid curing agent and cement, and the curing treatment of the sludge specifically includes the following steps: S51, based on the mix ratio of sludge and curing agent, and according to the sludge depth of each partition calculated in step S33, calculate the amount of cement and the amount of liquid curing agent required per cubic meter of sludge in each partition; S52, evenly spreading cement on the sludge surface in each partition; selecting a stirring point in each partition, stirring the sludge and cement at the stirring point by a stirring device, and spraying a liquid curing agent to the stirring point while stirring to solidify the sludge.

5. The in-situ solidification treatment process for river sludge according to claim 4, characterized in that: The mixing ratio of silt and curing agent is: silt: cement: liquid curing agent = 1~2: 9~12: 0.020~0.026; the optimal moisture content of silt is 45%.

6. The in-situ solidification treatment process for river sludge according to claim 1, characterized in that: The stirring device comprises: A mixer, which is provided with two mixing heads and an ash delivery pipe, wherein the output end of the ash delivery pipe is located between the two mixing heads; A mobile feed bin is connected to the input end of the ash delivery pipe through a hose, and the output end of the ash delivery pipe is connected to a spray gun. The mobile feed bin pumps liquid curing agent into the ash delivery pipe and sprays the liquid curing agent into the sludge to be solidified through the spray gun.

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