Environment-friendly desilting and sludge dewatering treatment process

Abstract

The invention relates to the technical field of river and lake sludge treatment, and provides an environment-friendly desilting and sludge dewatering treatment process which comprises the following steps: S1, building an artificial grid tank, a sludge sedimentation tank, a grid filtering channel, a turbulent flow mixing tank and a tail water tank near a river and lake to be treated; s2, the environment-friendly cutter suction dredger is placed in the river and lake to be treated, and a sludge conveying floating pipe is laid between the environment-friendly cutter suction dredger and the artificial grating pool; s3, building an overflow weir in the sludge sedimentation tank to form a sludge cavity and a water filtering cavity; a buoy mud pump is mounted in the sludge cavity and is connected with the grating filter tank through a pipeline; s4, the grid filtering channel is communicated with the turbulent flow mixing pool, and chemicals are added into the turbulent flow mixing pool through a chemical adding device for flocculation; and S5, conveying the flocculated sludge in the turbulent flow mixing pool into a high-pressure diaphragm filter press through a plunger pump and a pipeline, dehydrating and carrying away, and discharging filter-pressed effluent into a tail water pool. The process has the advantages of low cost, convenience in operation and simplicity in construction.

Description

Technical Field

[0001] The present application belongs to the technical field of river and lake sludge treatment, and more specifically, to an environmentally friendly dredging and sludge dewatering treatment process. Background Art

[0002] With the development of economy and the continuous acceleration of urbanization, various lakes and rivers in cities have become important carriers of people's domestic sewage discharge. Various industrial and domestic wastewater discharged into urban rivers, even after wastewater treatment, are likely to cause humus to accumulate in the lake bottom mud for a long time. As time goes by, when the deposited humus reaches a certain limit, the bottom mud of the lake is formed and released into the water body to form water pollution, which then affects the ecological balance of the water body, a large number of algae begin to grow, and the water body becomes eutrophic. Therefore, it is necessary to regularly desilt the lake.

[0003] At present, the main dredging methods for different types of lakes in China are dry dredging, semi-dry dredging and wet dredging. The sludge generated during the dredging process needs to be transported to a land mud dump for dehydration and drying. The sludge removed from the lake is generally large in volume, with a large amount of sludge and a high water content, which makes it very fluid. This requires a large area of ​​storage space, and the various pollutants contained in the sludge can easily cause secondary pollution to the environment. It is often difficult to select a suitable temporary mud dump nearby, and the selection of the location of the mud dump directly affects the overall capital investment of the dredging project. That is, the farther the mud dump is arranged, the longer the mud conveying pipeline is. At the same time, the longer the pipeline is, the greater the conveying pressure is, and the more pipeline booster devices are needed, resulting in the problem of difficulty in selecting a temporary land mud dump and large overall capital investment.

[0004] Therefore, in response to the above problems, it is urgent to develop an environmentally friendly dredging and sludge dewatering treatment process, which not only reduces the difficulty of selecting temporary land mud dumps and high capital investment costs in traditional lake dredging operations, but also solves the problems of low treatment efficiency of the sludge dewatering system, rough process design, and relatively high water content after treatment. Summary of the invention

[0005] In view of the technical problem of high investment cost in the above-mentioned prior art, the purpose of the embodiments of the present application is to provide an environmentally friendly dredging and sludge dewatering treatment process.

[0006] To achieve the above purpose, the technical solution adopted in this application is to provide an environmentally friendly dredging and sludge dewatering treatment process, comprising the following steps:

[0007] S1. Construct artificial screen pools, sludge sedimentation tanks, screen filtration channels, turbulent mixing tanks and tailwater tanks near the rivers and lakes to be treated;

[0008] S2, placing an environmental protection cutter suction boat in the river or lake to be treated, and laying a sludge transport floating pipe between the environmental protection cutter suction boat and the artificial grid pool;

[0009] S3, constructing an overflow weir in the sludge sedimentation tank to form a sludge chamber and a water filter chamber; installing a buoy sludge pump in the sludge chamber, and the buoy sludge pump is connected to the grille filter channel through a pipeline;

[0010] S4, the grid filter channel is connected to the turbulent mixing pool, and a dosing device is used to add a drug to the turbulent mixing pool for flocculation;

[0011] S5. The turbulent mixing tank is connected to the high-pressure diaphragm filter press through a pipeline and a plunger pump. After being dehydrated by the high-pressure diaphragm filter press, the sludge is transported away and dehydrated and discharged into the tailwater tank.

[0012] In one embodiment, the artificial grid pool includes a bottom and two side walls, the feed end of the artificial grid pool is open, the bottom is a hard inclined surface, a forklift can drive into the artificial grid pool, and a coarse grid mesh is arranged at the discharge end of the artificial grid pool, the aperture of which is 30-40 mm, and the lowest position of the artificial grid pool is higher than the highest water level of the sludge sedimentation tank.

[0013] In one embodiment, the overflow weir is built by stacking stone sheets or crushed stones, and has a trapezoidal cross-section.

[0014] In one embodiment, a chute is provided on the screen filter channel, a mechanical fine screen is provided in the screen filter channel, the chute includes at least an inclined screen mesh, the aperture of the inclined screen mesh is 10-20 mm, the sludge is discharged onto the inclined screen mesh, and the aperture of the mechanical fine screen is 3-10 mm.

[0015] In one embodiment, the length direction of the inclined grid mesh is perpendicular to the water flow direction of the grid filtration channel; the inclination angle of the inclined grid mesh is 50°-80°.

[0016] In one embodiment, a plurality of turbulent fins are provided in the turbulent mixing pool, a plurality of partitions are provided in the turbulent mixing pool to form a plurality of mixing chambers, and a stirring mechanism and a corresponding dosing device are provided in each mixing chamber.

[0017] In one embodiment, the high-pressure diaphragm filter press is arranged on a two-layer steel support or a board house, and a layer of the two-layer steel support or the board house can be entered and exited by a mud truck.

[0018] In one embodiment, the water pressing pipe of the high-pressure diaphragm filter press is connected to an auxiliary dehydration system through a water distributor and a return pipe, and a control valve is provided on the return pipe.

[0019] The beneficial effects of the environmentally friendly dredging and sludge dewatering treatment process provided by this application are:

[0020] By setting up an artificial screen pool, larger impurities in the sludge can be removed, and the impurities filtered out of the artificial screen pool can be cleaned regularly by a forklift, with low processing costs.

[0021] By setting an overflow weir in the sludge weighing battery, it has a filtering effect and can initially separate the sludge from the water. The construction is simple and the cost is low.

[0022] The sludge is filtered twice by setting up a grid filter channel to remove small and medium-sized impurities. The filtering operation is simple and the cost is low;

[0023] The sludge is dehydrated by setting up a high-pressure diaphragm filter press. A pressure regulating valve is set on the water distributor of the squeezing water pipe to facilitate real-time manual pressure adjustment for squeezing and dehydration, thereby improving the dehydration treatment efficiency. The sludge is transported out in a solid state for environmentally friendly treatment. BRIEF DESCRIPTION OF THE DRAWINGS

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

[0025] Figure 1 A schematic diagram of the overall process structure of the environmentally friendly dredging and sludge dewatering treatment process provided in the embodiment of the present application;

[0026] Figure 2 A schematic diagram of the connection structure between the river and lake to be treated and the artificial grid pool in the environmental dredging and sludge dewatering treatment process provided in the embodiment of the present application;

[0027] Figure 3 A schematic diagram of the positional relationship between an artificial grid pool and a sludge sedimentation pool in an environmentally friendly dredging and sludge dewatering treatment process provided in an embodiment of the present application;

[0028] Figure 4 A schematic diagram of the positional relationship between the grid filter channel, the turbulent mixing tank and the dosing device in the environmental dredging and sludge dewatering treatment process provided in the embodiment of the present application;

[0029] Figure 5 A schematic diagram of the positional relationship between a high-pressure diaphragm filter press, a tailwater tank, and an auxiliary dehydration system in the environmental dredging and sludge dehydration treatment process provided in an embodiment of the present application;

[0030] Figure 6 A schematic diagram of the structure of an artificial grid pool in an environmentally friendly dredging and sludge dewatering treatment process provided in an embodiment of the present application;

[0031] Figure 7 A schematic diagram of the main structure of a grid filter channel in an environmentally friendly dredging and sludge dewatering process provided in an embodiment of the present application;

[0032] Figure 8 A schematic diagram of the side structure of a grid filter channel in the environmental dredging and sludge dewatering treatment process provided in an embodiment of the present application.

[0033] Among them, the reference numerals in the figure are:

[0034] 1. Rivers and lakes to be treated; 2. Artificial screen pool; 3. Sludge sedimentation tank; 4. Screen filter channel; 5. Turbulent mixing tank; 6. Tailwater tank; 7. Environmental protection suction boat; 8. Sludge conveying floating pipe; 9. Overflow weir; 10. Sludge chamber; 11. Filter chamber; 12. Floating mud pump; 13. Dosing device; 14. Plunger pump; 15. High-pressure diaphragm filter press; 16. Bottom; 17. Side wall; 18. Screen mesh; 19. Chute; 20. Inclined screen mesh; 21. Mechanical fine screen; 22. Turbulent fin; 23. Partition; 24. Stirring mechanism; 25. Two-layer steel support; 26. Mud truck; 27. Return pipe; 28. Auxiliary dehydration system. DETAILED DESCRIPTION

[0035] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0036] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it can be directly on the other element or indirectly on the other element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or indirectly connected to the other element.

[0037] It should be understood that the terms "length", "width", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing the present application 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 should not be understood as a limitation on the present application.

[0038] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of this application, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0039] like Figure 1-Figure 8 As shown, an environmentally friendly dredging and sludge dewatering treatment process provided in an embodiment of the present application is now described. The environmentally friendly dredging and sludge dewatering treatment process comprises the following steps:

[0040] S1. Construct an artificial screen pool 2, a sludge sedimentation pool 3, a screen filter channel 4, a turbulent mixing pool 5 and a tailwater pool 6 near the river or lake to be treated 1. The artificial screen pool 2 is located higher than the sludge sedimentation pool 3 and the river or lake to be treated 1.

[0041] S2. Place the environmentally friendly dredging suction boat 7 in the river or lake to be treated 1, and lay a sludge conveying floating pipe 8 between the environmentally friendly dredging suction boat 7 and the artificial screen pool 2; the environmentally friendly dredging suction boat 7 is used to convey the sludge in the river or lake to be treated 1 into the artificial screen pool 2 through the sludge conveying floating pipe 8 for the first filtration of impurities, and the impurities are large-sized materials such as branches, grass, cloth, plastic, and iron.

[0042] S3. An overflow weir 9 is built in the sludge sedimentation tank 3 to form a sludge chamber 10 and a water filter chamber 11; a buoy mud pump 12 is installed in the sludge chamber 10, and the buoy mud pump 12 is connected to the grid filter channel 4 through a pipeline; the overflow weir 9 initially separates the sludge from the sludge, and the separated sludge is sent to the grid filter channel 4 through the buoy mud pump 12 or a small environmentally friendly suction boat 7 and a pipeline for a second filtration. The water filtered out by the overflow weir 9 can be discharged back into the river, lake or tailwater pool 6 to wait for treatment.

[0043] S4, the grid filter channel 4 is connected to the turbulent mixing tank 5, and the dosing device 13 is used to add chemicals into the turbulent mixing tank 5 for mixing and flocculation; after the impurities are removed by the grid filter channel 4, the sludge flows into the turbulent mixing tank 5, and the chemicals are added into the turbulent mixing tank 5 through the dosing device 13, so that the sludge undergoes a mixing and flocculation reaction.

[0044] S5, the turbulent mixing tank 5 is connected to the high-pressure diaphragm filter press 15 through a pipeline and a plunger pump 14. After being dehydrated by the high-pressure diaphragm filter press 15, the sludge is transported away and discharged into the tailwater tank 6 after dehydration. The sludge after the addition of the drug is pumped into the high-pressure diaphragm filter press 15 by the plunger pump 14 for dehydration. After dehydration, the solid mud blocks are obtained and transported away for subsequent environmental protection treatment. The water obtained by dehydration is discharged into the tailwater tank 6 for subsequent environmental protection treatment.

[0045] like Figure 2 , Figure 3 and Figure 6 As shown, in this embodiment, the artificial screen pool 2 includes a bottom 16 and two side walls 17, the two side walls 17 are arranged on the bottom 16 in parallel and at intervals, and the width between the two side walls 17 can be entered by a forklift. The feed end of the artificial screen pool 2 is open, and the bottom 16 is a hard inclined surface. A forklift can drive into the artificial screen pool 2 to transport the filtered impurities away. The discharge end of the artificial screen pool 2 is provided with a coarse screen mesh 18 with an aperture of 30-40mm for filtering large impurities. The lowest position of the artificial screen pool 2 is higher than the highest water level of the sludge sedimentation tank 3, and the sludge in the artificial screen pool 2 can automatically flow into the sludge sedimentation tank 3. In the prior art, mechanical coarse screens are often used for filtration, but their disadvantages are that the equipment consumes electricity, relies on water flow through the screen to operate, has limited operating conditions, requires large investment, and has a large maintenance workload. Compared with the mechanical coarse screens used in the prior art, the artificial screen pool 2 of this embodiment is located at a high position (higher than the position of the sludge sedimentation tank 3), and can automatically filter impurities by the deadweight of the sludge. It adopts an open type, has a large flow area, a low interception speed, a good interception effect, and can be entered by a forklift, which is convenient for regular mechanical cleaning of impurities, does not consume electricity, saves investment, is convenient for maintenance, and saves labor.

[0046] In this embodiment, the overflow weir 9 is made of stone or gravel, and the cross section is trapezoidal. In the prior art, triangular weirs or rectangular weirs are generally used for water distribution, which has the disadvantages of high cost, high construction difficulty, large investment, and the need to cooperate with concrete manufacturing. The overflow weir 9 of this embodiment has the function of rectifying the effluent uniformly and filtering the sludge, realizing the separation of sludge and water, and facilitating the subsequent sludge conditioning and dehydration treatment. In addition, the material of the overflow weir 9 is waste utilization such as stone or gravel, which is convenient for construction, low construction difficulty, low investment cost, and no need to set up a concrete sedimentation tank.

[0047] like Figure 4 , Figure 7 and Figure 8As shown, a chute 19 is provided on the grid filter channel 4, and a mechanical fine grid 21 is provided in the grid filter channel 4. The chute 19 includes at least an inclined grid net 20, and the aperture of the inclined grid net 20 is 10-20 mm. The sludge is discharged onto the inclined grid net 20, and the aperture of the mechanical fine grid 21 is 3-10 mm. Among them, the chute 19 is used to remove 10-20 mm sand and other impurities, and the mechanical fine grid 21 is used to filter fine impurities of 3-10 mm. Among them, the length direction of the inclined grid net 20 is perpendicular to the water flow direction of the grid filter channel 4; the inclination angle of the inclined grid net 20 is 50°-80°, and the lower end of the inclined grid net 20 can use a bucket car to receive the filtered impurities. The inclined grid net 20 can automatically roll down the filtered impurities under its own gravity, which is convenient for mud and water separation. Moreover, the inclined grid net 20 does not need electricity, and uses high-position gravity to automatically remove impurities. The equipment cost is low, the operation is convenient, and the failure is less, and it is convenient to maintain.

[0048] In this embodiment, if Figure 6 As shown, a number of turbulent fins 22 are provided in the turbulent mixing tank 5 for uniformly arranging the incoming water. A number of partitions 23 are provided in the turbulent mixing tank 5 to form a plurality of mixing chambers. A stirring mechanism 24 and a corresponding dosing device 13 are provided in each mixing chamber. The stirring mechanism 24 is used to accelerate the full mixing of sludge and reagents, ensure the coagulation reaction effect, and save time and space. After the sludge is conditioned by the turbulent mixing tank 5 for dosing and coagulation reaction, it is sent to the high-pressure diaphragm filter press 15 for sludge dewatering treatment through the plunger pump 14. Among them, the high-pressure diaphragm filter press 15 is set on a two-layer steel support 25 or a board house, and a mud truck 26 can be docked on one layer of the two-layer steel support 25 or the board house. This arrangement is convenient for the dehydrated sludge to be directly discharged to the sludge truck, without the need for secondary transportation, simplifying the process equipment and reducing costs. In the prior art, a filter press discharge hopper and a belt conveyor are generally configured, and the sludge needs to be secondary transported. There are many unloading and loading processes, a large amount of labor, cumbersome work and a large amount of equipment.

[0049] In this embodiment, the squeezing water pipe of the high-pressure diaphragm filter press 15 is connected to the auxiliary dehydration system 28 through the water divider and the return pipe 27, and a control valve is provided on the return pipe 27. The control valve is installed on the return pipe 27 of the high-pressure diaphragm filter press 15, which is convenient for manually adjusting the valve to make the pressure reach the squeezing requirement, and at the same time, it is close to the filter press, which is convenient for real-time monitoring of the squeezing state and operation. In the prior art, the control valve is installed on the squeezing water pump outlet pipe, which has the disadvantage that it is far away from the high-pressure diaphragm filter press 15, and it is inconvenient to operate and monitor the squeezing state of the filter press.

[0050] The above description is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present application should be included in the protection scope of the present application.

Claims

1. An environmentally friendly dredging and sludge dewatering process, characterized in that: The following steps are involved: S1. Constructing an artificial screen pool (2), a sludge sedimentation pool (3), a screen filtration channel (4), a turbulent mixing pool (5) and a tailwater pool (6) near the river or lake to be treated (1); S2, placing an environmentally friendly dredging vessel (7) in the river or lake to be treated (1), and laying a sludge transport floating pipe (8) between the environmentally friendly dredging vessel (7) and the artificial grid pool (2); S3, constructing an overflow weir (9) in the sludge sedimentation tank (3) to form a sludge chamber (10) and a water filter chamber (11); installing a buoy sludge pump (12) in the sludge chamber (10), and connecting the buoy sludge pump (12) to the grid filter channel (4) through a pipeline; S4, the grid filter channel (4) is connected to the turbulent mixing pool (5), and a drug is added to the turbulent mixing pool (5) through a drug adding device (13) for flocculation; S5. The turbulent mixing tank (5) is connected to the high-pressure membrane filter press (15) through a pipeline and a plunger pump (14). After being dehydrated by the high-pressure membrane filter press (15), the sludge is transported away and discharged into the tailwater tank (6).

2. The environmentally friendly dredging and sludge dewatering process according to claim 1, characterized in that: The artificial grate pool (2) comprises a bottom (16) and two side walls (17); the feed end of the artificial grate pool (2) is open, the bottom (16) is a hard inclined surface, a forklift can drive into the artificial grate pool (2), a coarse grate net (18) with an aperture of 30-40 mm is arranged at the discharge end of the artificial grate pool (2), and the lowest position of the artificial grate pool (2) is higher than the highest water level of the sludge sedimentation tank (3).

3. The environmentally friendly dredging and sludge dewatering process according to claim 2, characterized in that: The overflow weir (9) is built by stacking stone pieces or crushed stones, and has a trapezoidal cross section.

4. The environmentally friendly dredging and sludge dewatering process according to claim 3, characterized in that: The grid filter channel (4) is provided with a chute (19), the grid filter channel (4) is provided with a mechanical fine grid (21), the chute (19) at least comprises an inclined grid net (20), the aperture of the inclined grid net (20) is 10-20 mm, the sludge is discharged onto the inclined grid net (20), and the aperture of the mechanical fine grid (21) is 3-10 mm.

5. The environmentally friendly dredging and sludge dewatering process according to claim 4, characterized in that: The length direction of the inclined grid net (20) is perpendicular to the water flow direction of the grid filtering channel (4); the inclined angle of the inclined grid net (20) is 50°-80°.

6. The environmentally friendly dredging and sludge dewatering process according to claim 5, characterized in that: The turbulent mixing pool (5) is provided with a plurality of turbulent fins (22), and the turbulent mixing pool (5) is provided with a plurality of partitions (23) to form a plurality of mixing chambers, each of which is provided with a stirring mechanism (24) and a corresponding dosing device (13).

7. The environmentally friendly dredging and sludge dewatering process according to claim 6, characterized in that: The high-pressure membrane filter press (15) is arranged on a two-layer steel support (25) or a board house, and a mud truck (26) can enter and exit from one layer of the two-layer steel support (25) or the board house.

8. The environmentally friendly dredging and sludge dewatering process according to claim 7, characterized in that: The squeezing water pipe of the high-pressure membrane filter press (15) is connected to an auxiliary dehydration system (28) via a water distributor and a return pipe (27), and a control valve is provided on the return pipe (27).

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