Preparation equipment and preparation method of dredging pollution anti-diffusion medicament

Abstract

The invention discloses a dredging pollution anti-diffusion agent preparation device and a preparation method thereof. The preparation device comprises an anti-diffusion agent matrix preparation unit, a mineral-based anti-diffusion agent preparation unit, an iron powder-based anti-diffusion agent preparation unit and an anti-diffusion agent adding unit. The anti-diffusion agent matrix preparation unit comprises a storage barrel, a storage bin and a stirring tank, an outlet of the storage barrel and an outlet of the storage bin both lead to the stirring tank and are used for stirring to form a chitosan solution, and an outlet of the stirring tank is divided into two paths which are connected in parallel and are respectively communicated with the mineral-based anti-diffusion agent preparation unit and the iron powder-based anti-diffusion agent preparation unit; an outlet of the mineral-based anti-diffusion agent preparation unit and an outlet of the iron powder-based anti-diffusion agent preparation unit are communicated with the anti-diffusion agent adding unit for adding the prepared anti-diffusion agent. Through the combined effect of the mineral-based anti-diffusion agent and the iron-based anti-diffusion agent, the sedimentation rate can be increased through the magnetic adsorption effect, the flocculation agglomeration compactness is improved, and therefore the bottom mud anti-diffusion effect is improved.

Description

Technical Field

[0001] The invention relates to the technical field of environmental protection dredging, and in particular to a dredging pollution prevention and diffusion agent preparation device and a preparation method. Background Art

[0002] The desilting of rivers and lakes is currently the core measure for the internal source management of rivers and lakes. By cleaning the polluted sediments in rivers and lakes, the depth of the water body can be restored, the water quality can be improved, the water flow can be promoted, the ecological balance of the water body can be maintained, and the self-purification capacity of the water body can be improved. At present, the desilting of rivers and lakes generally adopts a cutter suction dredger, which uses a reamer to rotate and cut the sediment. The mud-water mixture formed is sucked into the mud discharge pipe through a sludge suction pump, and then transported to the mud discharge point through a pipeline for disposal. The reamer of a traditional cutter suction dredger is an open structure. The rotating movement of the reamer during the desilting process will disturb the sediment and water body, causing the sediment to suspend and spread, which will cause large-scale water pollution.

[0003] In order to solve the problem of suspended sediment diffusion during suction dredging, most of the current measures are to improve the structure of the reamer, and to reduce the contact area between the reamer and the water body by adding protective covers around the reamer, thereby reducing the diffusion of sediment and alleviating secondary water pollution. In the actual construction process of this technical measure, since part of the reamer will still be in contact with the sediment, and the movement of the protective cover will also disturb the sediment, it is inevitable that some of the sediment will be suspended and diffused due to the disturbance, and the water pollution problem still exists. Therefore, it is necessary to improve the existing dredging technology and process upgrade to form new dredging pollution prevention technology and equipment. Summary of the invention

[0004] The purpose of the present invention is to solve the shortcomings of the above-mentioned background technology and to provide a dredging pollution anti-diffusion agent preparation device and preparation method. By automatically preparing the anti-diffusion agent and adding the anti-diffusion agent to the suspended bottom mud near the dredging cutter head during the dredging process of the dredging vessel, the bottom mud is quickly settled and the suspension and diffusion of the bottom mud are reduced.

[0005] The technical solution of the present invention is: a dredging pollution anti-diffusion agent preparation device, characterized in that it comprises an anti-diffusion agent matrix preparation unit arranged on the hull of a dredger, a mineral-based anti-diffusion agent preparation unit, an iron powder-based anti-diffusion agent preparation unit and an anti-diffusion agent dosing unit arranged on a reamer device of the dredger; The anti-diffusion agent matrix preparation unit includes a storage barrel for storing dilute hydrochloric acid, a storage bin for storing chitosan powder, and a stirring tank. The storage barrel outlet and the storage bin outlet both lead to the stirring tank for stirring to form a chitosan solution. The stirring tank outlet is divided into two parallel paths, which lead to the mineral-based anti-diffusion agent preparation unit and the iron powder-based anti-diffusion agent preparation unit respectively. The outlet of the mineral-based anti-diffusion agent preparation unit and the outlet of the iron powder-based anti-diffusion agent preparation unit both lead to the anti-diffusion agent dosing unit for dosing the prepared anti-diffusion agent.

[0006] Preferably, a first water pump is provided between the storage barrel outlet and the stirring tank for conveying dilute hydrochloric acid, a first screw conveyor is provided between the storage bin outlet and the stirring tank for conveying chitosan, a first pipeline and a second pipeline in parallel are provided at the stirring tank outlet, a second water pump is provided on the first pipeline and the first pipeline outlet is connected to the mineral-based anti-diffusion agent preparation unit, a third water pump is provided on the second pipeline and the second pipeline outlet is connected to the iron powder-based anti-diffusion agent preparation unit.

[0007] Furthermore, the mineral-based anti-diffusion agent preparation unit includes a first mixing and stirring tank, a mineral powder silo, and a first temporary storage stirring tank. The first pipeline outlet and the mineral powder silo outlet both lead to the first mixing and stirring tank, and the first mixing and stirring tank outlet is connected to the first temporary storage stirring tank inlet.

[0008] Furthermore, a second screw conveyor is provided between the mineral powder silo outlet and the first mixing and stirring tank for conveying mineral powder, a fourth water pump is provided between the first mixing and stirring tank and the first temporary storage and stirring tank for conveying a mineral-based anti-diffusion agent, and a first external liquid level gauge is provided above the first temporary storage and stirring tank.

[0009] Furthermore, the iron powder-based anti-diffusion agent preparation unit includes a second mixing and stirring tank, an iron powder silo, and a second temporary storage stirring tank. The second pipeline outlet and the iron powder silo outlet both lead to the second mixing and stirring tank, and the second mixing and stirring tank outlet is connected to the second temporary storage stirring tank inlet.

[0010] Furthermore, a third screw conveyor is provided between the iron powder silo outlet and the second mixing and stirring tank for conveying iron powder, a fifth water pump is provided between the second mixing and stirring tank and the second temporary storage stirring tank for conveying iron powder-based anti-diffusion agent, and a second external liquid level gauge is provided above the second temporary storage stirring tank.

[0011] Furthermore, the anti-diffusion agent addition unit includes a first conduit and a second conduit, the outlet of the mineral-based anti-diffusion agent preparation unit is provided with a first high-pressure water pump connected to the first conduit, and the outlet of the iron powder-based anti-diffusion agent preparation unit is provided with a second high-pressure water pump connected to the second conduit, and the ends of the first conduit and the second conduit are both provided with nozzles on the reamer device.

[0012] Furthermore, the outlet of the first conduit is divided into two parallel paths, and the nozzles include a first nozzle and a second nozzle respectively arranged on the two parallel paths of the first conduit, and a third nozzle arranged at the outlet of the second conduit; The reamer device includes a reamer frame connected to the hull, and a reamer and a protective cover arranged at the end of the reamer frame. The first nozzle and the second nozzle are arranged on the reamer frame near the reamer, and the first nozzle sprays in a direction toward the end where the reamer is located, and the second nozzle sprays in a direction away from the end where the reamer is located. The third nozzle is arranged on the protective cover, and the spray direction is consistent with the direction of the reamer.

[0013] The present invention also provides a method for preparing any of the above dredging pollution prevention and diffusion agent preparation equipment, comprising: The chitosan and the dilute hydrochloric acid solution are stirred in a stirring tank in the anti-diffusion agent matrix preparation unit to prepare the anti-diffusion agent matrix; The anti-diffusion agent matrix and the mineral powder are mixed into the mineral-based anti-diffusion agent by using the first mixing and stirring tank in the mineral-based anti-diffusion agent preparation unit, and the mineral-based anti-diffusion agent is temporarily stored in the first temporary storage mixing tank; the anti-diffusion agent matrix and the iron powder are mixed into the iron powder-based anti-diffusion agent by using the second mixing and stirring tank in the iron powder-based anti-diffusion agent preparation unit, and the iron powder-based anti-diffusion agent is temporarily stored in the second temporary storage mixing tank; The mineral-based anti-diffusion agent in the first temporary storage stirring tank and the iron powder-based anti-diffusion agent in the second temporary storage stirring tank are added by using the anti-diffusion agent adding unit.

[0014] Preferably, when preparing the diffusion prevention agent matrix, the amount of chitosan used is 5-10 g per 1 L of dilute hydrochloric acid solution, and the mass concentration of the dilute hydrochloric acid solution is 1%-3%; When preparing a mineral-based anti-diffusion agent, the amount of mineral powder corresponding to 10-20 g per 1 L of anti-diffusion agent matrix is ​​10-20 g, and the mineral powder is a mixture of magnetite powder and barite powder in a mass ratio of 1:1-3, and the particle size is 50-200 meshes; when preparing an iron powder-based anti-diffusion agent, the amount of iron powder corresponding to 10-20 g per 1 L of anti-diffusion agent matrix is ​​10-20 g, and the iron powder particle size is 50-200 meshes; The injection rate of mineral-based anti-diffusion agent and iron powder-based anti-diffusion agent is 1-3 L / min. The beneficial effects of the present invention are: 1. The method of spreading anti-diffusion agents near the suction cutter is adopted to control the suspended sediment pollution, which can further solve the problem of suspended sediment diffusion outside the anti-diffusion cover; the preparation of the anti-diffusion agent adopts chitosan, mineral materials, and iron powder harmless and environmentally friendly materials. Compared with conventional flocculants, it has less environmental harm and is not easy to cause secondary pollution of water bodies. In addition, the iron powder and magnetite components in the anti-diffusion agent can adsorb and purify some pollutants to purify the water body.

[0015] 2. The aggregates formed after the mineral-based anti-diffusion agent and the iron-based anti-diffusion agent capture the suspended matter have a large specific gravity and a fast sedimentation rate, which effectively reduces the diffusion range of the suspended matter; the combined action of the mineral-based anti-diffusion agent and the iron-based anti-diffusion agent can enhance the sedimentation rate through magnetic adsorption, increase the density of flocculation agglomerates, and thus enhance the sedimentation effect.

[0016] 3. In the anti-diffusion agent matrix preparation unit, the storage barrel is used to store dilute hydrochloric acid, the storage silo is used to store chitosan, and the stirring tank is used to mix the dilute hydrochloric acid and chitosan into a chitosan solution (i.e., the anti-diffusion agent matrix). Moreover, the chitosan solution is transported to the mineral-based anti-diffusion agent preparation unit and the iron powder-based anti-diffusion agent preparation unit respectively through the first pipeline and the second pipeline connected in parallel, so as to quickly and conveniently complete the preparation of the two diffusants.

[0017] 4. In the mineral-based anti-diffusion agent preparation unit, the mineral powder silo is used to store mineral powder, the first mixing and stirring tank is used to mix the mineral powder and chitosan solution into a mineral-based anti-diffusion agent, the first temporary storage stirring tank is convenient for storing the prepared anti-diffusion agent, the stirring operation of the first temporary storage stirring tank is convenient for maintaining the uniform dispersion state of the mineral-based anti-diffusion agent, and the first external liquid level gauge can monitor the liquid level in the barrel in real time, and stop the operation of the front equipment when the liquid level is too high.

[0018] 5. In the iron powder-based anti-diffusion agent preparation unit, the iron powder silo is used to store iron powder, the second mixing and stirring tank is used to mix the iron powder and chitosan solution into the iron powder-based anti-diffusion agent, the second temporary storage stirring tank is convenient for storing the prepared anti-diffusion agent, the stirring operation of the second temporary storage stirring tank is convenient for maintaining the uniform dispersion state of the iron powder-based anti-diffusion agent, and the second external liquid level gauge can monitor the liquid level in the barrel in real time, and stop the operation of the front equipment when the liquid level is too high.

[0019] 6. In the anti-diffusion agent dosing unit, the mineral-based anti-diffusion agent is added through the first and second nozzles, and the iron powder-based anti-diffusion agent is added through the third nozzle. The mineral-based anti-diffusion agent will quickly undergo flocculation and agglomeration after contacting the suspended matter, causing the suspended sludge to aggregate into agglomerates; due to the addition of mineral powder, the specific gravity of the sludge increases after flocculation, and the sedimentation is accelerated. The iron powder-based anti-diffusion agent will also quickly undergo flocculation and agglomeration after contacting the suspended matter, causing the suspended sludge to aggregate into agglomerates. At the same time, the iron powder will also react with the pollutants in the sludge to remove the pollutants in the sludge. The magnetite powder in the mineral-based anti-diffusion agent will produce a magnetic adsorption effect with the iron powder in the iron powder-based anti-diffusion agent during the sinking process, accelerating the sedimentation of the suspended sludge, making the formed flocculation agglomerates denser, thereby improving the anti-diffusion effect of the sludge. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

[0021] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0022] Figure 1 A schematic diagram of the equipment structure for preparing anti-diffusion agents for dredging pollution; Figure 2 Schematic diagram of the method for preparing the anti-diffusion agent for dredging pollution; Wherein: 1-storage barrel 2-first water pump 3-mixing tank 4-storage silo, 5-first screw conveyor 6-third water pump 7-second water pump 8-first mixing and stirring tank 9-second mixing and stirring tank 10-mineral powder silo 11-iron powder silo 12-second screw conveyor 13-third screw conveyor 14-fourth water pump 15-fifth water pump 16-first temporary mixing tank 17-first external measuring liquid level gauge 18-first high-pressure water pump 19-second high-pressure water pump 20-second temporary mixing tank 21-second external measuring liquid level gauge 22-first nozzle 23-second nozzle 24-third nozzle 25-protective cover 26-reamer, 27-reamer frame 28-first conduit 29-second conduit 31-first pipeline 32-second pipeline. DETAILED DESCRIPTION

[0023] In order to make the purpose, technical scheme and advantages of the embodiments of the present application clearer, the technical scheme in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without making creative work belong to the scope of protection of this application. Unless otherwise specified, various raw materials and equipment used in this application can be purchased from the market or prepared by existing methods.

[0024] like Figure 1 As shown, the present invention provides a dredging pollution anti-diffusion agent preparation device, including an anti-diffusion agent matrix preparation unit, a mineral-based anti-diffusion agent preparation unit, an iron powder-based anti-diffusion agent preparation unit, and an anti-diffusion agent addition unit. The anti-diffusion agent matrix preparation unit, the mineral-based anti-diffusion agent preparation unit, and the iron powder-based anti-diffusion agent preparation unit are all arranged on the hull of the dredger, and the anti-diffusion agent addition unit is arranged on the reamer device at the bottom of the dredger.

[0025] The specific structure of the anti-diffusion agent matrix preparation unit is as follows: it includes a storage barrel 1 for storing dilute hydrochloric acid, a storage bin 4 for storing chitosan powder, and a stirring tank 3. The outlets of the storage barrel 1 and the storage bin 4 lead to two inlets on the top of the stirring tank 3 respectively. The stirring tank 3 is used to stir and form a chitosan solution (i.e., an anti-diffusion agent matrix). A first water pump 2 is provided between the outlet of the storage barrel 1 and the stirring tank 3 for conveying dilute hydrochloric acid. A first screw conveyor 5 is provided between the outlet of the storage bin 4 and the stirring tank 3 for uniformly adding chitosan into the stirring tank. The outlet of the stirring tank 3 is provided with a first parallel pipeline 31 and a second pipeline 32. A second water pump 7 is provided on the first pipeline 31 and the outlet of the first pipeline 31 is connected to the mineral-based anti-diffusion agent preparation unit. A third water pump 6 is provided on the second pipeline 32 and the outlet of the second pipeline 32 is connected to the iron powder-based anti-diffusion agent preparation unit.

[0026] The specific structure of the mineral-based anti-diffusion agent preparation unit is as follows: it includes a first mixing and stirring tank 8, a mineral powder silo 10, and a first temporary storage stirring tank 16. The outlet of the first pipeline 31 and the outlet of the mineral powder silo 10 lead to two inlets on the top of the first mixing and stirring tank 8 respectively, and the outlet of the first mixing and stirring tank 8 is connected with the inlet of the first temporary storage stirring tank 16. A second screw conveyor 12 is provided between the outlet of the mineral powder silo 10 and the first mixing and stirring tank 8 for conveying mineral powder, a fourth water pump 14 is provided between the outlet of the first mixing and stirring tank 8 and the inlet of the first temporary storage stirring tank 16 for conveying mineral-based anti-diffusion agent, and a first external liquid level gauge 17 is provided above the first temporary storage stirring tank 16 to monitor the liquid level of the mineral-based anti-diffusion agent in the tank in real time.

[0027] The specific structure of the iron powder-based anti-diffusion agent preparation unit is as follows: it includes a second mixing and stirring tank 9, an iron powder silo 11, and a second temporary storage stirring tank 20. The outlet of the second pipeline 32 and the outlet of the iron powder silo 11 lead to two inlets on the top of the second mixing and stirring tank 9 respectively, and the outlet of the second mixing and stirring tank 9 is connected to the inlet of the second temporary storage stirring tank 20. A third screw conveyor 13 is provided between the outlet of the iron powder silo 11 and the second mixing and stirring tank 9 for conveying iron powder, a fifth water pump 15 is provided between the outlet of the second mixing and stirring tank 9 and the inlet of the second temporary storage stirring tank 20 for conveying iron powder-based anti-diffusion agent, and a second external liquid level gauge 21 is provided above the second temporary storage stirring tank 20 to monitor the liquid level of the iron powder-based anti-diffusion agent in the tank in real time.

[0028] The specific structure of the anti-diffusion agent addition unit is as follows: it includes a first conduit 28 and a second conduit 29, the outlet of the mineral-based anti-diffusion agent preparation unit (i.e., the outlet of the first temporary storage stirring tank 16) is provided with a first high-pressure water pump 18 connected to the first conduit 28, the outlet of the iron powder-based anti-diffusion agent preparation unit (i.e., the outlet of the second temporary storage stirring tank 20) ​​is provided with a second high-pressure water pump 19 connected to the second conduit 29, the outlet of the first conduit 28 is divided into two parallel paths, the ends of the two parallel paths are respectively provided with a first nozzle 22 and a second nozzle 23, and a third nozzle 24 is provided at the outlet of the second conduit 29.

[0029] The reamer device is consistent with the existing structure, including a reamer frame 27 connected to the hull, a reamer 26 and a protective cover 25 arranged at the end of the reamer frame 27. The first nozzle 22 and the second nozzle 23 are arranged on the reamer frame 27 at a position 1 to 2 meters away from the suction cutter head, and the first nozzle 22 sprays toward the end where the reamer is located, and the second nozzle 23 sprays away from the end where the reamer is located. The third nozzle 24 is arranged on the protective cover 25 and the spray direction is consistent with the reamer. The first nozzle 22 and the second nozzle 23 spraying the iron powder-based anti-diffusion agent are arranged in opposite directions, in order to expand the coverage area of ​​the iron powder-based anti-diffusion agent and suppress the suspension and diffusion of the bottom mud as much as possible.

[0030] like Figure 2 As shown, the preparation method using the above dredging pollution prevention and diffusion agent preparation equipment is as follows: Step S1: using the stirring tank 3 in the anti-diffusion agent matrix preparation unit to stir chitosan and dilute hydrochloric acid solution to prepare an anti-diffusion agent matrix, specifically: The first water pump 2 transports the dilute hydrochloric acid solution (mass concentration 1%~3%) in the storage barrel 1 to the stirring tank 3, and then the first screw conveyor 5 operates to add the chitosan powder in the storage bin 4 into the stirring tank 3, and the ratio of dilute hydrochloric acid to chitosan is 1L:5~10g. At the same time, the agitator of the stirring tank 3 operates to uniformly dissolve chitosan in the dilute hydrochloric acid solution to obtain a chitosan solution (i.e., an anti-diffusion agent matrix), and the anti-diffusion agent matrix is ​​transported to the first mixing stirring tank 8 and the second mixing stirring tank 9 by the second water pump 7 and the third water pump 6 respectively.

[0031] Step S2: using the first mixing and stirring tank 8 in the mineral-based anti-diffusion agent preparation unit to mix the anti-diffusion agent matrix and the mineral powder into a mineral-based anti-diffusion agent, and temporarily storing it in the first temporary storage stirring tank 16; using the second mixing and stirring tank 9 in the iron powder-based anti-diffusion agent preparation unit to mix the anti-diffusion agent matrix and iron powder into an iron powder-based anti-diffusion agent, and temporarily storing it in the second temporary storage stirring tank 20.

[0032] Specifically, after the first mixing and stirring tank 8 receives the chitosan solution, the second screw conveyor 12 is operated to add the mineral powder stored in the mineral powder bin 10 into the first mixing and stirring tank 8, the chitosan solution and the mineral powder addition ratio = 1L: 10~20g, the mineral powder is a mixture of magnetite powder and barite powder in a mass ratio of 1:1~3, and the mineral powder particle size is 50~200 mesh. The first mixing and stirring tank 8 is stirred at high speed for 5~10min to disperse the mineral powder in the chitosan solution to form a stable mineral-based anti-diffusion agent. After the mineral-based anti-diffusion agent is stirred, it is input into the first temporary storage stirring tank 16 through the fourth water pump 14. The first temporary storage stirring tank 16 is continuously stirred and operated to maintain the uniform dispersion state of the mineral-based anti-diffusion agent. The first external liquid level gauge 17 on the upper part of the first temporary storage stirring tank 16 monitors the liquid level in the tank in real time, and stops the operation of the dispensing equipment before the first temporary storage stirring tank 16 when the liquid level is too high.

[0033] Similarly, after receiving the chitosan solution, the second mixing and stirring tank 9, the third screw conveyor 13 runs to add the iron powder in the iron powder bin 11 into the second mixing and stirring tank 9, the chitosan solution and iron powder addition ratio = 1L: 10~20g, the iron powder particle size is 50~200 mesh, and the second mixing and stirring tank 9 is stirred at high speed for 5~10min to disperse the iron powder in the chitosan solution to form a stable iron powder-based anti-diffusion agent. After the iron powder-based anti-diffusion agent is stirred, it is input into the second temporary storage stirring tank 20 through the fifth water pump 15. The second temporary storage stirring tank 20 is continuously stirred and operated to maintain the uniform dispersion state of the mineral-based anti-diffusion agent. The second external measurement liquid level gauge 21 on the upper part of the second temporary storage stirring tank 20 monitors the liquid level in the tank in real time, and stops the operation of the dispensing equipment before the second temporary storage stirring tank 20 when the liquid level is too high.

[0034] Step S3: using the anti-diffusion agent adding unit to add the mineral-based anti-diffusion agent in the first temporary storage stirring tank 16 and the iron powder-based anti-diffusion agent in the second temporary storage stirring tank 20 .

[0035] Specifically, the mineral-based anti-diffusion agent in the first temporary storage stirring tank 16 is transported to the first nozzle 22 and the second nozzle 23 through the first high-pressure water pump 18 through the first conduit 28, and is sprayed into the desilting water body. At the same time, the iron powder-based anti-diffusion agent in the second temporary storage stirring tank 20 is transported to the third nozzle 24 through the second high-pressure water pump 19 through the second conduit 29, and is sprayed into the desilting water body. The injection rate of the two anti-diffusion agents is 1~3L / min. After the mineral-based anti-diffusion agent contacts the suspended matter, it will quickly undergo flocculation and agglomeration, causing the suspended sludge to aggregate into agglomerates; due to the addition of mineral powder, the specific gravity of the sludge after flocculation increases, and the sedimentation is accelerated. After the iron powder-based anti-diffusion agent contacts the suspended matter, it will also quickly undergo flocculation and agglomeration, causing the suspended sludge to aggregate into agglomerates. At the same time, the iron powder will also react with the pollutants in the sludge to remove the pollutants in the sludge. The magnetite powder in the mineral-based anti-diffusion agent will produce magnetic adsorption with the iron powder in the iron powder-based anti-diffusion agent during the sinking process, accelerating the sedimentation of suspended sediment and making the formed flocculation clusters denser, thereby improving the sediment anti-diffusion effect.

[0036] The present application is further described below in conjunction with specific embodiments.

[0037] The lake is 3-5m deep and is dredged by a suction dredging vessel. The above-mentioned dredging pollution prevention agent preparation equipment is installed on the dredging vessel. Before the dredging vessel operates, the prevention agent is prepared and stored.

[0038] The preparation method using the above dredging pollution prevention and diffusion agent preparation equipment is as follows: Step S1: The first water pump 2 transports the dilute hydrochloric acid solution (mass concentration 2%) in the storage tank 1 to the stirring tank 3, and the first screw conveyor 5 operates to add chitosan powder into the stirring tank 3, and the ratio of dilute hydrochloric acid to chitosan is 1L:8g. At the same time, the agitator of the stirring tank 3 operates to evenly dissolve the chitosan in the dilute hydrochloric acid solution, and the dissolved chitosan solution is transported to the first mixing stirring tank 8 and the second mixing stirring tank 9 by the second water pump 7 and the third water pump 6 respectively.

[0039] Step S2: After the first mixing and stirring tank 8 receives the chitosan solution, the second screw conveyor 12 is operated to add the mineral powder stored in the mineral powder bin 10 into the first mixing and stirring tank 8, the chitosan solution and the mineral powder addition ratio = 1L: 15g, the mineral powder is a mixture of magnetite powder and barite powder in a mass ratio of 1: 3, and the mineral powder particle size is 50~200 mesh. The first mixing and stirring tank 8 is stirred at high speed for 5~10min to disperse the mineral powder in the chitosan solution to form a stable mineral-based anti-diffusion agent. After the mineral-based anti-diffusion agent is stirred, it is input into the first temporary stirring tank 16 through the fourth water pump 14. The first temporary stirring tank 16 is continuously stirred and operated to maintain the uniform dispersion state of the mineral-based anti-diffusion agent. The first external liquid level gauge 17 on the upper part of the first temporary stirring tank 16 monitors the liquid level in the tank in real time. When the liquid level is too high, the operation of the dispensing equipment before the first temporary stirring tank 16 is stopped.

[0040] Similarly, after the second mixing and stirring tank 9 receives the chitosan solution, the third screw conveyor 13 is operated to add the iron powder in the iron powder bin 11 into the second mixing and stirring tank 9, the chitosan solution and iron powder addition ratio = 1L: 15g, the iron powder particle size is 50~200 mesh, and the second mixing and stirring tank 9 is stirred at high speed for 5~10min to disperse the iron powder in the chitosan solution to form a stable iron powder-based anti-diffusion agent. After the iron powder-based anti-diffusion agent is stirred, it is input into the second temporary storage stirring tank 20 through the fifth water pump 15. The second temporary storage stirring tank 20 is continuously stirred and operated to maintain the uniform dispersion state of the mineral-based anti-diffusion agent. The second external liquid level gauge 21 on the upper part of the second temporary storage stirring tank 20 monitors the liquid level in the tank in real time. When the liquid level is too high, the operation of the dispensing equipment before the second temporary storage stirring tank 20 is stopped.

[0041] Step S3: After the preparation and storage of the anti-diffusion agent are completed, the two anti-diffusion agents are added simultaneously. The process is as follows: The mineral-based anti-diffusion agent in the first temporary storage stirring tank 16 is transported to the first nozzle 22 and the second nozzle 23 through the first high-pressure water pump 18 through the first conduit 28, and is sprayed into the dredging water body. At the same time, the iron powder-based anti-diffusion agent in the second temporary storage stirring tank 20 is transported to the third nozzle 24 through the second high-pressure water pump 19 through the second conduit 29, and is sprayed into the dredging water body. The injection rate of the two anti-diffusion agents is 2L / min. After the two anti-diffusion agents come into contact with the suspended matter, they will quickly undergo flocculation and agglomeration, allowing the suspended sediment to aggregate into agglomerates, which has an anti-diffusion effect on the sediment. When the dredging ship does not use this equipment, there is a 5-10m wide sediment suspension zone during the dredging process; when this equipment is used, the width of the sediment suspension zone during the dredging process is only 1-3m, and the sediment pollution anti-diffusion effect is significant.

[0042] During the addition of the anti-diffusion agent, two types of anti-diffusion agents can be continuously prepared at the front end of the first temporary storage stirring tank 16 and the second temporary storage stirring tank 20, and replenished into the temporary storage stirring tank in time to ensure the demand for anti-diffusion agent during continuous operation.

Claims

1. A dredging pollution prevention and diffusion agent preparation equipment, characterized in that: It includes an anti-diffusion agent matrix preparation unit arranged on the hull of a dredger, a mineral-based anti-diffusion agent preparation unit, an iron powder-based anti-diffusion agent preparation unit, and an anti-diffusion agent dosing unit arranged on a reamer device of the dredger; The anti-diffusion agent matrix preparation unit comprises a storage barrel (1) for storing dilute hydrochloric acid, a storage bin (4) for storing chitosan powder, and a stirring tank (3); the outlet of the storage barrel (1) and the outlet of the storage bin (4) both lead to the stirring tank (3) for stirring to form a chitosan solution; the outlet of the stirring tank (3) is divided into two parallel paths, leading to the mineral-based anti-diffusion agent preparation unit and the iron powder-based anti-diffusion agent preparation unit respectively; The outlet of the mineral-based anti-diffusion agent preparation unit and the outlet of the iron powder-based anti-diffusion agent preparation unit both lead to the anti-diffusion agent dosing unit for dosing the prepared anti-diffusion agent.

2. The dredging pollution prevention and diffusion agent preparation equipment according to claim 1, characterized in that: A first water pump (2) for conveying dilute hydrochloric acid is provided between the outlet of the storage barrel (1) and the stirring tank (3); a first screw conveyor (5) for conveying chitosan is provided between the outlet of the storage bin (4) and the stirring tank (3); a first pipeline (31) and a second pipeline (32) connected in parallel are provided at the outlet of the stirring tank (3); a second water pump (7) is provided on the first pipeline (31) and the outlet of the first pipeline (31) is connected to a mineral-based anti-diffusion agent preparation unit; a third water pump (6) is provided on the second pipeline (32) and the outlet of the second pipeline (32) is connected to an iron powder-based anti-diffusion agent preparation unit.

3. The dredging pollution prevention and diffusion agent preparation equipment according to claim 2, characterized in that: The mineral-based anti-diffusion agent preparation unit comprises a first mixing and stirring tank (8), a mineral powder bin (10), and a first temporary storage and stirring tank (16); the outlet of the first pipeline (31) and the outlet of the mineral powder bin (10) both lead to the first mixing and stirring tank (8); and the outlet of the first mixing and stirring tank (8) is connected to the inlet of the first temporary storage and stirring tank (16).

4. The dredging pollution prevention and diffusion agent preparation equipment according to claim 3, characterized in that: A second screw conveyor (12) is provided between the outlet of the mineral powder silo (10) and the first mixing and stirring tank (8) for conveying mineral powder, a fourth water pump (14) is provided between the first mixing and stirring tank (8) and the first temporary storage and stirring tank (16) for conveying a mineral-based anti-diffusion agent, and a first external liquid level gauge (17) is provided above the first temporary storage and stirring tank (16).

5. The dredging pollution prevention and diffusion agent preparation equipment according to claim 2, characterized in that: The iron powder-based anti-diffusion agent preparation unit comprises a second mixing and stirring tank (9), an iron powder material bin (11), and a second temporary storage and stirring tank (20); the outlet of the second pipeline (32) and the outlet of the iron powder material bin (11) both lead to the second mixing and stirring tank (9); and the outlet of the second mixing and stirring tank (9) is connected to the inlet of the second temporary storage and stirring tank (20).

6. The dredging pollution prevention and diffusion agent preparation equipment according to claim 5, characterized in that: A third screw conveyor (13) is provided between the outlet of the iron powder silo (11) and the second mixing and stirring tank (9) for conveying iron powder, a fifth water pump (15) is provided between the second mixing and stirring tank (9) and the second temporary storage and stirring tank (20) for conveying an iron powder-based anti-diffusion agent, and a second external liquid level gauge (21) is provided above the second temporary storage and stirring tank (20).

7. The dredging pollution prevention and diffusion agent preparation equipment as claimed in claim 1, characterized in that: The anti-diffusion agent dosing unit comprises a first conduit (28) and a second conduit (29); the outlet of the mineral-based anti-diffusion agent preparation unit is provided with a first high-pressure water pump (18) connected to the first conduit (28); the outlet of the iron powder-based anti-diffusion agent preparation unit is provided with a second high-pressure water pump (19) connected to the second conduit (29); and nozzles are provided at the ends of the first conduit (28) and the second conduit (29) on a reamer device.

8. The dredging pollution prevention and diffusion agent preparation equipment as claimed in claim 7, characterized in that: The outlet of the first conduit (28) is divided into two parallel paths, and the nozzles include a first nozzle (22) and a second nozzle (23) respectively arranged on the two parallel paths of the first conduit (28), and a third nozzle (24) arranged at the outlet of the second conduit (29); The reamer device comprises a reamer frame (27) connected to the hull, and a reamer (26) and a protective cover (25) arranged at the end of the reamer frame (27); the first nozzle (22) and the second nozzle (23) are arranged on the reamer frame (27) near the reamer, and the first nozzle (22) sprays in a direction toward the end where the reamer is located, and the second nozzle (23) sprays in a direction away from the end where the reamer is located; the third nozzle (24) is arranged on the protective cover (25), and the spray direction is consistent with the direction of the reamer.

9. A method for preparing a dredging pollution prevention agent using any one of the above 1 to 8 preparation equipment, characterized in that: include: Using a stirring tank (3) in the anti-diffusion agent matrix preparation unit, chitosan and a dilute hydrochloric acid solution are stirred to prepare an anti-diffusion agent matrix; The anti-diffusion agent matrix and the mineral powder are mixed into the mineral-based anti-diffusion agent by using the first mixing and stirring tank (8) in the mineral-based anti-diffusion agent preparation unit, and the mineral-based anti-diffusion agent is temporarily stored in the first temporary storage and stirring tank (16); the anti-diffusion agent matrix and iron powder are mixed into the iron powder-based anti-diffusion agent by using the second mixing and stirring tank (9) in the iron powder-based anti-diffusion agent preparation unit, and the iron powder-based anti-diffusion agent is temporarily stored in the second temporary storage and stirring tank (20); The anti-diffusion agent dosing unit is used to add the mineral-based anti-diffusion agent in the first temporary storage stirring tank (16) and the iron powder-based anti-diffusion agent in the second temporary storage stirring tank (20).

10. The method for preparing the dredging pollution prevention and diffusion agent preparation equipment according to claim 9, characterized in that: When preparing the diffusion prevention agent matrix, the amount of chitosan used is 5-10g per 1L of dilute hydrochloric acid solution, and the mass concentration of the dilute hydrochloric acid solution is 1%-3%; When preparing a mineral-based anti-diffusion agent, the amount of mineral powder corresponding to 10-20 g per 1 L of anti-diffusion agent matrix is ​​10-20 g, and the mineral powder is a mixture of magnetite powder and barite powder in a mass ratio of 1:1-3, and the particle size is 50-200 meshes; when preparing an iron powder-based anti-diffusion agent, the amount of iron powder corresponding to 10-20 g per 1 L of anti-diffusion agent matrix is ​​10-20 g, and the iron powder particle size is 50-200 meshes; The injection rate of mineral-based anti-diffusion agent and iron powder-based anti-diffusion agent is 1~3L / min.

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