Channel dredging device and method

Abstract

The invention provides a channel dredging device and method, the channel dredging device comprises a compressed air supply unit, an aeration disc and a large-diameter hose, the compressed air supply unit is connected with an air inlet of the aeration disc through an air source pipeline, and the lower end of the large-diameter hose is fixed right above an air outlet of the aeration disc. The channel dredging device has the beneficial effects that the disturbance and carrying effect of bubble floating and the vertical transportation capacity of the chimney effect are combined, and channel dredging operation can be efficiently and continuously conducted.

Description

Technical Field

[0001] The present invention relates to the technical field of waterway dredging, and in particular to a waterway dredging device and method. Background Art

[0002] Existing channel dredging technologies include cutter suction dredgers, jet silt flushing, ecological silt flushing, and trailing suction dredger assisted aeration silt flushing. Among them, the cutter suction dredger sucks in the bottom silt through mud pumps and cutters and transports it through pipelines. Its advantages are continuous operation, high efficiency, and good applicability to dredging depth. Its disadvantages are large investment, heavy equipment, and poor maneuverability; the stirring of the cutter may cause the suspension and diffusion of sediment; and it has poor adaptability to hard mud layers; jet silt flushing uses high-pressure water jets to flush the bottom sediment, so that it is re-suspended and transported with the water flow. Its advantages are relatively low cost and flexible operation, but its disadvantages are easy to cause It causes large-scale diffusion of silt and secondary sedimentation; it is highly dependent on water flow conditions and is not suitable for areas with slow flow rates; it is difficult to accurately control the scope of dredging; ecological dredging uses biological methods such as microbial degradation or plant absorption to remove pollutants or consolidate silt, which is environmentally friendly. The disadvantage is that the dredging cycle is long and the efficiency is low, and it is not suitable for emergency or large-scale dredging needs; dredging with assisted aeration by aeration vessels attempts to combine an aeration device to disturb the bottom sediment through bubbles. The disadvantage is that after the bubbles are started, the silt will settle quickly, and the suspension effect is very unsatisfactory, resulting in the inability to effectively transport the silt to the designated location, and the dredging efficiency is limited. Summary of the Invention

[0003] The present invention provides a highly efficient, environmentally friendly, low-energy, and adaptable channel desilting device. By combining the disturbance and entrainment of rising bubbles with the vertical transport capability of the chimney effect, the device converts silt at the bottom of the channel into floating mud under specific tidal conditions and transports it out of the channel via natural water flow. This achieves continuous, precise, and economical desilting while minimizing environmental disturbance and secondary pollution. This effectively addresses the challenges of rapid sedimentation and unsatisfactory suspension effects in existing aeration desilting technologies.

[0004] The principle of bubble buoyancy (air flotation) is that when gas forms small bubbles in a liquid, the bubbles, because their density is much lower than that of the liquid, will move upward under the action of buoyancy. If there are suspended particles in the liquid, the bubbles may attach to the surface of the particles during their rise, or the bubbles may disturb the particles, causing the particles to float up with the bubbles. This principle is widely used in air flotation separation technology in wastewater treatment, where bubbles bring fine suspended matter to the liquid surface.

[0005] The chimney effect generally refers to air movement caused by temperature or density differences between the inside and outside of a structure. In high-rise buildings, this manifests as vertical air movement caused by a pressure differential between the inside and outside of the building. This principle can be applied to hydraulics: when the top and bottom ends of a vertical pipe are in different flow rates or pressure zones, the higher-flowing side experiences lower pressure, while the slower-flowing side experiences higher pressure. This pressure differential can create an upward or downward flow within the pipe.

[0006] The technical solution adopted by the present invention is: a waterway dredging device, including a compressed air supply unit, an aeration plate and a large-diameter hose, the compressed air supply unit is connected to the air inlet of the aeration plate through an air source pipeline, and the lower end of the large-diameter hose is fixed directly above the air outlet of the aeration plate.

[0007] In offshore areas, the surface flow velocity is generally 1.5-2 times that of the bottom flow velocity. If the surface flow is dominated by wind, the velocity difference will be even greater. In this case, the surface water flow velocity is fast and the bottom water flow velocity is slow, which will form an upward flow in the pipe.

[0008] Optionally, the compressed air supply unit is an air tank or an air compressor on the ship side.

[0009] Optionally, a high-pressure pump is further included, and the water outlet of the high-pressure pump is connected to the interior of the aeration disk.

[0010] Optionally, the aeration plate is made of a corrosion-resistant material, and the large-diameter hose is made of a flexible and corrosion-resistant material.

[0011] Optionally, an auxiliary water pump is provided in the large-diameter hose, and the auxiliary water pump is fixed near the upper end of the large-diameter hose.

[0012] Optionally, a floating plate or an air bag is connected to the outlet of the large-diameter hose.

[0013] A method for dredging a waterway comprises the following steps:

[0014] (1) The aeration plate is placed in advance at a location in the waterway that is prone to siltation. The upper end of the large-diameter hose is connected to a position in the water close to the water surface but not above the water surface. The environmental parameters such as tidal flow rate, water depth, and siltation in the waterway area are continuously monitored to provide a decision-making basis for dredging operations.

[0015] (2) Based on monitoring data, the optimal time for dredging is determined when the flow velocity is fastest at low tide or when the flow velocity reaches a preset threshold;

[0016] (3) Open the compressed air supply unit to deliver compressed air to the aeration plate located at the bottom of the water through the air source pipeline; when the air outlet of the aeration plate is blocked by silt, start the high-pressure pump and use high-pressure water flow to clean the silt covering the aeration plate;

[0017] (4) The air bubbles carry the floating mud into the large diameter hose. Due to the flow velocity difference at both ends of the large diameter hose, the floating mud entering the large diameter hose rises to the water surface along the large diameter hose and drifts away from the channel with the ebb tide.

[0018] (5) Turn off the compressed air supply unit to complete the dredging operation.

[0019] The advantages and positive effects of the present invention are as follows: due to the adoption of the above-mentioned technical scheme, by combining the disturbance and carrying effect of the rising bubbles with the vertical transport capacity of the chimney effect, the silt at the bottom of the channel can be efficiently and continuously converted into floating mud and lifted to the water surface, effectively solving the problems of rapid sedimentation and unsatisfactory suspension effect of silt in existing aeration dredging, greatly improving the dredging efficiency, and being particularly suitable for deep-water channels that are difficult to reach or inefficient due to traditional mechanical dredging; since the silt is mainly transported vertically in the hose during the dredging process and is directly transported out with the strong ebb tide, the diffusion and suspension of sediment in the channel is minimized, thereby effectively reducing the risk of secondary pollution during the dredging process, and being more friendly to the aquatic environment; it can effectively handle fine particles and loose floating mud that are difficult to remove by traditional methods, and expand the adaptability of dredging operations. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a structural diagram of a device in a specific embodiment of the present invention;

[0021] Figure 2 is a flow chart of a method according to a specific embodiment of the present invention;

[0022] In the figure: 1. Compressed air supply unit; 2. Air source pipeline; 3. Aeration plate; 4. Large diameter hose. DETAILED DESCRIPTION

[0023] The present invention will be further described in detail below with reference to specific embodiments. It should be understood that the specific embodiments described herein are intended only to explain the present invention and are not intended to limit the present invention. In the description of the present invention, it should be understood that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "back," "left," "right," "vertical," "horizontal," "top," "bottom," "inside," "outside," and the like, indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings and are intended only to facilitate the description of the present invention and simplify the description. They do not indicate or imply that the devices or components referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as limiting the present invention. In the description of the present invention, it should be noted that, unless otherwise expressly specified or limited, the terms "installed," "connected," and "connected" should be understood in a broad sense. For example, they can be fixedly connected, detachably connected, or integrally connected; they can be mechanically connected or electrically connected; they can be directly connected, indirectly connected through an intermediate medium, or they can be internally connected between two components. For those skilled in the art, the specific meanings of the above terms in the present invention can be understood based on specific circumstances.

[0024] like Figure 1 As shown, the present invention provides a channel dredging device, including an air compressor, an aeration plate 3 and a large-diameter hose 4. The air compressor is connected to the air inlet of the high aeration plate 3 through an air source pipeline 2, and the lower end of the large-diameter hose 4 is fixed directly above the air outlet of the aeration plate 3.

[0025] The aeration plate 3 is made of corrosion-resistant material, and the large-diameter hose 4 is made of flexible and corrosion-resistant material.

[0026] The large diameter hose 4 is provided with an auxiliary water pump 5 for increasing the upward thrust inside the large diameter hose 4. The auxiliary water pump 5 is fixed near the upper end of the large diameter hose 4. A float or air bag is connected to the outlet of the large diameter hose 4 to increase its buoyancy, so that the outlet position of the large diameter hose 4 is maintained below the water surface. In order to prevent the outlet of the aeration plate 3 from being clogged with silt, the silt removal device also includes a high-pressure water pump. The outlet of the high-pressure water pump is connected to the interior of the aeration plate. When the interior of the aeration plate 3 is clogged, the high-pressure water pump can be used to impact the air holes in the aeration plate. When the outlet of the aeration plate 3 is clogged with silt, the high-pressure water pump can be started to remove the silt at the outlet of the aeration plate 3.

[0027] The above structure is used as follows: the aeration plate 3 is pre-placed at a location prone to siltation in the waterway and fixed at a specified depth. The aeration plate 3 will be buried by the silt deposited above. The aeration plate 3 usually adopts a disc-shaped structure with a large number of fine pores, which can disperse the compressed air transmitted from the air source pipeline 2 into a large number of uniform tiny bubbles. When the bubbles are released from the aeration plate 3, they disturb and stir the silt layer at the bottom, loosening it. During the rising process, some of the tiny bubbles directly adhere to the surface of the silt particles and carry the silt particles upward through the buoyancy of the bubbles; the other part is entrained and suspended by the surrounding silt particles through the disturbed water flow formed by the rising bubbles, thereby converting the solidified or semi-solidified silt at the bottom into "floating mud" with a higher water content and fluidity, and forming an upward-flowing mixing area.

[0028] The lower end of the large-diameter hose 4 directly above the aeration plate 3 can be fixed directly above the bottom aeration plate 3 using a ship-mounted / bottom-mounted bracket, with the other end connected to the sea surface (but not above the water surface). The large-diameter hose 4 is made of a flexible and corrosion-resistant material, such as a reinforced rubber hose or a polymer composite tube. Its diameter does not change significantly due to external water pressure during operation, but the tube body has a certain degree of flexibility and can swing or move appropriately with the direction of water flow (such as tidal flow) to adapt to water flow conditions and ensure that the top outlet is always in the effective flow field. The large diameter helps to reduce water flow resistance and avoid silt blockage.

[0029] The main function of the large diameter hose 4 is to collect the bubbles generated by the aeration plate 3 and the carried floating mud and guide them upward so that the floating mud reaches the water surface position at the designated location. In this process, the floating mud will be confined to a specific area to prevent it from spreading over a large area during the dredging process.

[0030] A method of dredging a waterway, such as Figure 2 As shown, the following steps are included:

[0031] (1) The aeration plate 3 is placed in advance at a location in the waterway where siltation is likely to occur. The upper end of the large-diameter hose 4 is connected to a position in the water close to the water surface but not above the water surface. Environmental parameters such as tidal flow rate, water depth, and siltation in the waterway area are continuously monitored to provide a decision-making basis for dredging operations.

[0032] (2) Based on monitoring data, the optimal time for dredging is determined when the flow velocity is fastest at low tide or when the flow velocity reaches a preset threshold. At this time, the velocity difference between the surface water flow and the bottom water flow is the largest, which is conducive to enhancing the chimney effect. At the same time, the transport capacity of the low tide is the strongest.

[0033] (3) Open the compressed air supply unit 1 to deliver the compressed air to the aeration plate 3 located at the bottom of the water through the air source pipeline 2; if the outlet of the aeration plate 3 is blocked by silt, open the high-pressure water pump to remove the silt at the outlet of the aeration plate 3;

[0034] (4) The aeration plate 3 releases a large number of tiny bubbles, which disturb and stir the silt layer at the bottom during the rising process, and attach to the silt particles, or carry the silt particles upward through the stirring of the water flow. The originally relatively solidified silt gradually becomes loose under the action of the bubbles, forming "floating mud" with good fluidity; the floating mud carried up by the bubbles and the upward water flow formed by the bubbles jointly guide the floating mud into the large diameter hose above; inside the large diameter hose 4, when the ebb tide speed is fast, the surface water flow speed of the channel is much greater than the bottom water flow speed. According to Bernoulli's principle, the surface water flow speed is much faster than the bottom water flow speed. Fast water flow leads to low pressure, while slow bottom water flow leads to high pressure. The top outlet of the large-diameter hose 4 is in the low-pressure area of ​​the surface layer, while the bottom is in the high-pressure area of ​​the bottom layer. This external pressure difference and the upwelling formed by the bubbles inside the large-diameter hose 4 work together to produce a powerful "chimney effect", which transports the floating mud and water mixture in the hose vertically upward to the surface of the seawater. The floating mud transported to the surface of the seawater coincides with the peak of the ebb tide. The strong ebb tide quickly carries the surface floating mud away from the waterway and transports it to a deep water area or a specific sediment accumulation area outside the waterway where it does not affect shipping, thereby achieving the effect of dredging the waterway.

[0035] (5) When the tidal flow rate slows down or the dredging target is achieved, the compressed air supply unit 1 is turned off to complete a dredging operation.

[0036] The embodiments of the present invention are described in detail above, but the contents described are only preferred embodiments of the present invention and should not be considered to limit the scope of the present invention. All equivalent changes and improvements made within the scope of the present invention should still fall within the scope of the patent coverage of the present invention.

Claims

1. A waterway dredging device, characterized in that: It includes a compressed air supply unit, an aeration disk and a large-diameter hose. The compressed air supply unit is connected to the air inlet of the aeration disk through an air source pipeline, and the lower end of the large-diameter hose is fixed just above the air outlet of the aeration disk.

2. The waterway dredging device according to claim 1, characterized in that: The compressed air supply unit is an air storage tank or an air compressor on the ship side.

3. The channel dredging device according to claim 1, characterized in that: It also includes a high-pressure pump, and the water outlet of the high-pressure pump is connected to the interior of the aeration disk.

4. The waterway dredging device according to claim 1, characterized in that: The aeration plate is made of corrosion-resistant material, and the large-diameter hose is made of flexible and corrosion-resistant material.

5. The waterway dredging device according to any one of claims 1 to 4, characterized in that: An auxiliary water pump is arranged in the large-diameter hose and is fixed near the upper end of the large-diameter hose.

6. The waterway dredging device according to claim 5, characterized in that: The outlet of the large-diameter hose is connected with a floating plate or an air bag.

7. A method for clearing a waterway using the waterway clearing device according to any one of claims 3 to 6, comprising the following steps: (1) The aeration plate is placed in advance at a location in the waterway that is prone to siltation. The upper end of the large-diameter hose is connected to a position in the water close to the water surface but not above the water surface. The environmental parameters such as tidal flow rate, water depth, and siltation in the waterway area are continuously monitored to provide a decision-making basis for dredging operations. (2) Based on monitoring data, the optimal time for dredging is determined when the flow velocity is fastest at low tide or when the flow velocity reaches a preset threshold; (3) Open the compressed air supply unit to deliver compressed air to the aeration plate located at the bottom of the water through the air source pipeline; when the air outlet of the aeration plate is blocked by silt, start the high-pressure water pump to use high-pressure water flow to clean the silt covering the aeration plate; (4) The air bubbles carry the floating mud into the large diameter hose. Due to the flow velocity difference at both ends of the large diameter hose, the floating mud entering the large diameter hose rises to the water surface along the large diameter hose and drifts away from the channel with the ebb tide. (5) Turn off the compressed air supply unit to complete the dredging operation.

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