An underwater blasting environmental protection method

Abstract

This application relates to the field of underwater environmental protection, and in particular to a method for underwater blasting environmental protection. It includes sequentially deploying a bubble curtain and an antifouling curtain around a predetermined blasting zone; placing a package containing a water treatment flocculant within the blasting zone or in the water immediately above it; linking the release trigger condition to the blasting operation; and implementing underwater blasting to trigger the release of the flocculant, allowing it to mix with suspended sediment. The bubble curtain weakens the shock wave and, in conjunction with the antifouling curtain, hinders sediment diffusion, while the flocculant promotes the settling of suspended solids. The application also describes the flocculant composition, packaging material and placement method, the formation and fixing method of the bubble curtain and antifouling curtain, their placement distance, and the steps of monitoring water turbidity and replenishing flocculant. This application achieves the technical effects of weakening underwater shock waves, hindering the diffusion of suspended sediment, accelerating the settling of fine suspended solids, and realizing rapid water purification after blasting.

Description

Technical Field

[0001] This application relates to the field of underwater environmental protection, and in particular to an underwater blasting environmental protection method. Background Technology

[0002] In engineering fields such as waterway blasting and port construction, underwater blasting is an extremely important method. It can efficiently remove underwater rock obstacles, facilitating the smooth progress of related projects and possessing irreplaceable value for waterway dredging and port infrastructure construction. With the continuous expansion of project scale and ongoing technological development, the application of underwater blasting is becoming increasingly widespread, playing a crucial role in promoting water transport development and enhancing port throughput capacity. However, a series of environmental problems caused by underwater blasting have gradually emerged, attracting widespread attention.

[0003] Currently, the industry mainly adopts two types of measures to address environmental protection issues related to underwater blasting: passive interception and post-explosion treatment. Passive interception commonly involves using anti-fouling curtains (or anti-fouling screens). This method sets up a physical barrier downstream of the blasting zone to attempt to prevent the spread of suspended sediment. Another commonly used technology is the bubble curtain, which releases compressed air through underwater pipes to form a rising bubble wall, primarily used to reduce the damage of underwater shock waves to surrounding structures such as bridge piers and dams. Post-explosion treatment typically involves purifying the water after the blasting is completed.

[0004] However, these existing technologies have significant drawbacks. Pollution curtains have poor impact resistance; under strong blast shock waves, they are prone to tearing, anchoring failure, or even being washed away entirely, leading to complete protection failure. While bubble curtains can weaken shock waves to some extent, their effect on impeding suspended sediment is limited, and fine particles can easily diffuse through the gaps between the bubbles. Moreover, neither pollution curtains nor bubble curtains can effectively address the long-term suspension of sediment caused by river disturbances, resulting in poor protection, low efficiency, and high costs. Summary of the Invention

[0005] To address the aforementioned technical problems, this application provides an underwater blasting environmental protection method.

[0006] The underwater blasting environmental protection method provided in this application adopts the following technical solution: An environmental protection method for underwater blasting includes the following steps: S1: A bubble curtain and a dirt-proof curtain are sequentially deployed around the perimeter of the predetermined blasting zone, with the dirt-proof curtain located downstream of the bubble curtain. S2: Place a package containing water treatment flocculant in the blast zone or in the water body immediately above it, and associate the release triggering condition of the package with the blasting operation; S3: Conduct underwater blasting. The blasting operation simultaneously triggers the flocculant packaging to release the flocculant inside. The released flocculant rapidly mixes with the suspended sediment in the violently turbulent water generated by the blast. S4: The bubble curtain weakens the underwater shock wave generated by the explosion and works together with the antifouling curtain to block the spread of suspended sediment downstream. At the same time, the flocculant promotes the flocculation of fine suspended particles and accelerates their sedimentation, thereby achieving rapid purification of the water after the explosion.

[0007] By adopting the above technical solution, a multi-level protection and purification system with synergistic effects is constructed by organically combining the bubble curtain, the antifouling curtain, and the immediate addition of flocculant. The bubble curtain, as the first line of defense, effectively weakens the shock wave from the blast center, protecting the downstream antifouling curtain from damage; simultaneously, both physically block the spread of suspended sediment. By synchronously triggering the release of flocculant with the blasting process, the agent can rapidly and thoroughly mix with high-concentration suspended sediment through the intense hydraulic turbulence generated at the moment of blasting, greatly improving the efficiency of flocculation and sedimentation. This method replaces the passive interception method of traditional transmission, changing to "interception + active purification," controlling pollution from both the source and process, significantly shortening the time for water to clear from turbid, and solving the problems of weak protection and delayed purification in traditional methods.

[0008] Preferably, the flocculant is a composite flocculant, comprising inorganic coagulants and organic polymeric flocculants.

[0009] By adopting the above technical solution and using a composite flocculant containing inorganic coagulants and organic polymeric flocculants, a synergistic effect can be achieved by utilizing their different mechanisms of action. The inorganic coagulant primarily functions by neutralizing and compressing the electrical double layer, destabilizing and agglomerating fine colloidal particles to form micro-flocs. The organic polymeric flocculant, on the other hand, utilizes the adsorption, bridging, and entrapment effects of its long molecular chains to rapidly connect these micro-flocs into large, dense flocs. This two-stage process of "coagulation followed by flocculation" removes fine suspended particles from water more quickly and thoroughly than using a single flocculant, thereby significantly accelerating sedimentation and improving purification efficiency.

[0010] Preferably, the inorganic coagulant is polyaluminum chloride, and the organic polymeric flocculant is biodegradable anionic polyacrylamide.

[0011] By adopting the above technical solution, the inorganic coagulant is specifically limited to polyaluminum chloride (PAC), which has the advantages of a wide pH range adaptability, rapid and robust floc formation, and stable turbidity removal effect; the organic polymeric flocculant is limited to biodegradable anionic polyacrylamide (APAM), which, while leveraging its efficient bridging and trapping effects to greatly improve settling velocity, avoids the long-term environmental residue risks that may arise from traditional polyacrylamide due to its biodegradable properties. This combination, while ensuring excellent rapid water purification efficiency, enhances its friendliness to the aquatic environment and meets the requirements of green and environmentally friendly engineering.

[0012] Preferably, the flocculant packaging is a sealed capsule made of a water-soluble or water-degradable material.

[0013] By adopting the above technical solution and using water-soluble or water-degradable materials to make the flocculant packaging, precise controlled release of the agent and self-elimination of the packaging material are achieved. At the moment of explosion, the shock wave or high-speed water flow can easily destroy, dissolve, or degrade the packaging, allowing the flocculant to be released instantly and completely, ensuring that the agent intervenes at the very beginning of pollution formation. Simultaneously, the packaging material itself dissolves or degrades in water, eliminating the need for recycling and avoiding secondary pollutants that may be generated by traditional packaging materials. This simplifies subsequent cleanup work and makes the entire dosing process more environmentally friendly and convenient.

[0014] Preferably, the flocculant packaging body is mounted on an independent suspended carrier within the blast zone via a connector, and the shock wave or high-speed water flow generated by the blast is sufficient to destroy the packaging body material, thereby achieving instantaneous release.

[0015] By employing the above technical solution, the flocculant packaging is placed on an independent suspended carrier within the blast zone, ensuring the carrier remains stably suspended in a predetermined water layer before blasting. Upon blasting, the shockwave and the resulting extremely high-velocity water flow instantly tear the packaging, allowing the flocculant to be released directly into the most contaminated and concentrated area. This method fully utilizes the immense energy generated by the blast as the driving force for flocculant diffusion and mixing, achieving optimal initial mixing of the flocculant and pollutants. This creates the most critical conditions for subsequent efficient flocculation and sedimentation, with mixing efficiency far exceeding that of subsequent additions to already diffused areas.

[0016] Preferably, the bubble curtain is formed by releasing compressed air through an air distribution pipe laid on the riverbed or seabed, and the air distribution pipe is fixed to the seabed by an anchoring device; the antifouling curtain includes a float, a curtain fabric and a bottom counterweight component, and is fixed to a set position by anchor ropes and anchor blocks.

[0017] By employing the above technical solution, the air distribution pipe is fixed to the bottom of the water using an anchoring device, ensuring the structural stability and positional stability of the bubble curtain when subjected to the impact of bursting water flow, thus forming a continuous and complete bubble barrier. The antifouling curtain adopts a classic structure including a float, curtain fabric, and bottom counterweight components, and is fixed by anchor ropes and anchor blocks, allowing it to deploy vertically in the water, forming a three-dimensional interception surface from the water surface to near the bottom. The float provides buoyancy, the curtain fabric constitutes the main body of the barrier, and the counterweight components keep the lower end of the curtain fabric taut and close to the riverbed, effectively preventing sediment from bypassing from the bottom. The combination of these two achieves effective interception of suspended sediment across the entire cross-section.

[0018] Preferably, the distance L1 from the location of the bubble curtain to the edge of the blast zone is set according to the blasting equivalent, which is used to weaken the shock wave to the point that it does not damage the strength of the downstream anti-fouling curtain; the distance L2 from the location of the anti-fouling curtain to the downstream side of the bubble curtain is 10-30m.

[0019] By adopting the above technical solution, the distance L1 of the bubble curtain is set according to the explosive equivalent. Its core purpose is to ensure, through precise distance control, that the intensity of the shock wave reaching the antifouling curtain after sufficient attenuation by the bubble curtain has decreased to within its structural safety threshold, thus scientifically solving the problem of the antifouling curtain being easily damaged. Setting the antifouling curtain 10-30 meters downstream ensures that it is within the effective protection range of the bubble curtain while also placing it in an area where turbulence is still relatively strong and sediment has not yet fully dispersed. This allows for the most effective interception of most of the floating and dispersing suspended sediment, achieving a balance between protective effectiveness and structural safety.

[0020] Preferably, step S3 further includes a monitoring step based on the turbidity of the water body, and a step of adding flocculant to the downstream side of the antifouling curtain.

[0021] By employing the above technical solution, turbidity monitoring downstream of the antifouling curtain allows for real-time and objective evaluation of the initial blasting purification effect. If the turbidity exceeds the predetermined standard, it indicates that some fine particles of sediment have penetrated or bypassed the pre-filter. In this case, adding flocculant downstream can perform secondary purification on these "escaped" pollutants. This step, as a final safeguard, ensures that regardless of the initial purification effect, the downstream water will ultimately meet the clarity requirements, greatly improving the reliability and adaptability of the entire method.

[0022] In summary, this application includes at least one of the following beneficial technical effects: 1. The bubble curtain effectively weakens underwater shock waves, protects the downstream antifouling curtain from damage, and together the two physically block the spread of suspended sediment. 2. The use of composite flocculants can remove fine suspended particles in water more quickly and thoroughly, significantly accelerating the settling speed and improving the purification effect; 3. The flocculant packaging releases the flocculant at the moment of blasting, using the blast energy to fully mix the agent with the sediment, achieving instantaneous addition, and adding it in situ, improving purification efficiency and significantly shortening the time it takes for the water to change from turbid to clear. Attached Figure Description

[0023] Figure 1 This is a flowchart illustrating the steps of an underwater blasting environmental protection method according to an embodiment of this application. Detailed Implementation

[0024] The following is in conjunction with the appendix Figure 1 This application will be described in further detail.

[0025] This application discloses an underwater blasting environmental protection method, referring to... Figure 1 The process includes several steps: sequentially deploying bubble curtains and antifouling curtains around the predetermined blasting zone; setting up packaging containing water treatment flocculants; conducting underwater blasting to release and mix the flocculants; and using bubble curtains and antifouling curtains to trap sediment and accelerate the settling of flocculants to purify the water. Specifically, by sequentially deploying bubble curtains and antifouling curtains, the bubble curtains weaken the shock wave and protect the antifouling curtains, both working together to trap suspended sediment. Simultaneously, the flocculant packaging is linked to the blasting operation, releasing the flocculants during the blast to mix with the suspended sediment. This achieves effective protection against shock waves, interception of suspended matter, and rapid water purification. This is because the bubble curtains reflect, scatter, and absorb energy from the shock wave, weakening its intensity; the antifouling curtains physically intercept suspended sediment; and the flocculants cause fine suspended particles to flocculate and settle. This addresses the environmental problems caused by underwater blasting from multiple perspectives.

[0026] Specifically, in the step of sequentially deploying the bubble curtain and anti-fouling curtain around the predetermined blasting zone, the formation of the bubble curtain requires air distribution pipes and an air compressor. The air distribution pipes are generally made of PVC, a material with good corrosion resistance and a certain degree of strength. Their shape is typically a closed or U-shaped pipe loop surrounding the blasting zone, with multiple air distribution pipes connected by flanges. Air holes are drilled into the air distribution pipes, for example, two rows of staggered 3mm diameter holes spaced 10cm apart, to ensure even release of compressed air and form the bubble curtain. Alternatively, steel pipes can be used as the air distribution pipe material; steel pipes are stronger but relatively heavier, and installation may be more difficult. An air compressor is used to provide compressed air. Its exhaust pressure and volume need to be adjusted according to the actual situation. For example, with an exhaust pressure of 0.8 MPa and an exhaust volume of 20 m³ / min, the air compressor is turned on before the blast, and the supply pressure is adjusted to 0.5-0.6 MPa. This will create a continuous, dense rising bubble wall, or bubble curtain, about 1-2 meters thick, above the air distribution pipe. The air distribution pipe is fixed to the seabed by an anchoring device, which can be a heavy block such as a concrete anchor, to ensure the structural stability and positional fixation of the air distribution pipe when subjected to the impact of the blasting water flow.

[0027] A pollution control curtain consists of a float, a curtain fabric, and a bottom counterweight. The float is typically made of HDPE buoys, offering good buoyancy and corrosion resistance, and can be up to 300mm in diameter. The curtain fabric is usually made of high-strength polyester filament spun clay fabric, such as 500g / m², which has excellent tensile strength and permeability. The bottom counterweight can be a steel chain, for example, weighing 20kg / m, which keeps the lower end of the curtain fabric taut and close to the riverbed, preventing silt from flowing around from the bottom. Multiple pollution control curtains are spliced ​​together to the required total length using connectors, and then connected to weighted blocks such as grab buckets via anchor ropes. These anchor blocks are placed on the riverbed to ensure the stability of the entire pollution control curtain system under the action of water flow and impact currents. Alternative floats can be foam blocks, and the curtain fabric can also be made of other high-strength, permeable materials.

[0028] The step of placing the package containing the water treatment flocculant in or immediately above the blast zone involves using a sealed capsule made of a water-soluble or water-degradable material, such as a water-soluble polyvinyl alcohol (PVA) film. This film dissolves completely in room temperature water within approximately 10 minutes, enabling precise controlled release of the agent and self-elimination of the packaging material. Alternatively, starch-based biodegradable materials can be used, with the appropriate biodegradable material selected based on the installation and blast timing. The only requirement is that the package does not dissolve in the water before the explosive detonates. The package is then attached to an independent suspended carrier within the blast zone via connectors. This suspended carrier can be made of polylactic acid, starch-based plastics, wood, bamboo, or waterproofed plant fibers (such as coconut fiber) to form buoys or floats. In the natural environment, these buoys can be decomposed by microorganisms over months to years, ultimately transforming into water, carbon dioxide, and biomass, without persistent pollution. The suspended carrier is then evenly secured to the buoys with thin ropes. When the shock wave or high-speed water flow generated by the explosion acts on the packaging, it is enough to destroy the packaging material and achieve instantaneous release, allowing the flocculant to be released directly in the area with the most core pollution and the highest concentration.

[0029] Underwater blasting is conducted, and the blasting operation simultaneously triggers the release of flocculant from its packaging. The released flocculant rapidly mixes with the suspended sediment in the violently turbulent water generated by the blast. At the moment of blast, the shock wave and high-speed water flow cause the packaging to rupture and dissolve, rapidly dispersing and releasing the internal composite flocculant into the water. The extreme turbulence generated by the explosion provides intense mixing conditions between the flocculant and sediment particles, allowing the flocculant to come into full contact with fine sediment particles in a short time.

[0030] The bubble curtain weakens the underwater shock wave generated by the blast and, together with the antifouling curtain, hinders the downstream diffusion of suspended sediment. Simultaneously, the flocculant promotes the flocculation and accelerated sedimentation of fine suspended particles, thus achieving rapid purification of the water body after the blast. The bubble curtain reflects, scatters, and absorbs energy from the shock wave, significantly attenuating its intensity. The rising bubble flow also lifts and disturbs coarser sediment particles. The antifouling curtain, with its robust structure and anchoring system, remains intact, effectively blocking most of the floating and horizontally diffusing suspended sediment flocs. Polyaluminum chloride in the flocculant rapidly neutralizes the surface charge of sediment particles, destabilizing them to form micro-flocs. The long molecular chains of biodegradable anionic polyacrylamide, through adsorption bridging and trapping, connect the micro-flocs into large, dense "lump flocs," which rapidly settle to the riverbed under gravity.

[0031] Step S3 also includes a monitoring step based on water turbidity and a step of adding flocculant downstream of the antifouling curtain. Approximately 10 minutes after the blast, a portable turbidimeter is used to monitor the water about 50 meters downstream of the antifouling curtain 3. If the monitoring results show that the turbidity is lower than the predetermined standard, it indicates that the purification is successful. If the monitoring finds that the turbidity in some areas is still high, a small dosing boat is used to add a small amount of the same type of liquid polyaluminum chloride or biodegradable anionic polyacrylamide solution to the high-turbidity area downstream of the antifouling curtain for "point-to-point" enhanced flocculation to ensure that the downstream water finally meets the standards.

[0032] The implementation principle of this embodiment is as follows: This method organically combines a bubble curtain, a fouling screen, and the immediate addition of flocculant to construct a synergistic multi-level protection and purification system. The bubble curtain, as the first line of defense, effectively weakens the shock wave and protects the downstream fouling screen; both work together to physically block the spread of suspended sediment. By synchronously triggering the release of flocculant with the blasting process, the intense hydraulic turbulence at the moment of blasting allows the agent to mix rapidly and thoroughly with high-concentration suspended sediment, greatly improving the efficiency of flocculation and sedimentation. Simultaneously, through turbidity monitoring and supplementary flocculant addition, it is ensured that regardless of the initial purification effect, the downstream water body will ultimately meet the clarity requirements. This solves the problems of weak protection and delayed purification in traditional methods, improves the reliability and adaptability of the entire method, and reduces the environmental impact of underwater blasting.

Claims

1. A method for environmental protection during underwater blasting, characterized in that: Includes the following steps: S1: A bubble curtain and a dirt-proof curtain are sequentially deployed around the perimeter of the predetermined blasting zone, with the dirt-proof curtain located downstream of the bubble curtain. S2: Place a package containing water treatment flocculant in the blast zone or in the water body immediately above it, and associate the release triggering condition of the package with the blasting operation; S3: Conduct underwater blasting. The blasting operation simultaneously triggers the flocculant packaging to release the flocculant inside. The released flocculant rapidly mixes with the suspended sediment in the violently turbulent water generated by the blast. S4: The bubble curtain weakens the underwater shock wave generated by the explosion and works together with the antifouling curtain to block the spread of suspended sediment downstream. At the same time, the flocculant promotes the flocculation of fine suspended particles and accelerates their sedimentation, thereby achieving rapid purification of the water after the explosion.

2. The underwater blasting environmental protection method according to claim 1, characterized in that: The flocculant is a composite flocculant, comprising inorganic coagulants and organic polymeric flocculants.

3. The underwater blasting environmental protection method according to claim 2, characterized in that: The inorganic coagulant is polyaluminum chloride, and the organic polymeric flocculant is biodegradable anionic polyacrylamide.

4. A method for environmental protection during underwater blasting according to any one of claims 1-3, characterized in that: The flocculant packaging is a sealed capsule made of water-soluble or water-degradable materials.

5. The underwater blasting environmental protection method according to claim 4, characterized in that: The flocculant package is mounted on an independent suspended carrier within the blast zone via a connector. The shock wave or high-speed water flow generated by the blast is sufficient to destroy the package material, thereby achieving instantaneous release.

6. The underwater blasting environmental protection method according to claim 1, characterized in that: The bubble curtain is formed by releasing compressed air through air distribution pipes laid on the riverbed or seabed, and the air distribution pipes are fixed to the seabed by anchoring devices; the antifouling curtain includes a float, a curtain fabric and a bottom counterweight component, and is fixed to a set position by anchor ropes and anchor blocks.

7. The underwater blasting environmental protection method according to claim 6, characterized in that: The distance L1 between the location of the bubble curtain and the edge of the blast zone is set according to the blasting equivalent, and is used to weaken the shock wave to the point that it will not damage the strength of the downstream anti-fouling curtain; the distance L2 between the location of the anti-fouling curtain and the downstream side of the bubble curtain is 10-30m.

8. The underwater blasting environmental protection method according to claim 1, characterized in that: Step S3 also includes a monitoring step based on the turbidity of the water body, and a step of adding flocculant to the downstream side of the antifouling curtain.

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