Foldable in-situ electro-phytoremediation device for heavy metal contaminated sediment in river and lake

Abstract

This invention belongs to the field of river and lake sediment remediation technology, and discloses a foldable in-situ electrodynamic-phytoremediation device for heavy metal-contaminated river and lake sediments, comprising: a horizontal frame; including horizontally arranged insulating tubes; a longitudinal frame including two vertically arranged support tubes respectively connected to the bottom of the two insulating tubes, a first connector, and a second connector, the first connector having a first through hole and a second through hole arranged vertically, the second connector having a third through hole, each support tube being connected to two diagonal braces; and the two diagonal braces being detachably connected to the two ends of the same insulating tube, the longitudinal frame being made of insulating material; a horizontal rotating shaft passing through the first through hole of the first connector; an aquatic plant planting tray being arranged on the horizontal frame; a horizontally arranged cathode electrode rod and a horizontally arranged anode electrode rod being installed in the second and third through holes with multiple perforations on the wall surface, respectively; and connected to the negative and positive terminals of a power supply respectively through wires.

Description

Technical Field

[0001] This invention pertains to river and lake sediment remediation technology, and specifically relates to an in-situ electrodynamic-phytoremediation device for heavy metal-contaminated river and lake sediments. Background Technology

[0002] Heavy metals in water bodies accumulate in the surface sediment through adsorption, complexation, and precipitation. When environmental conditions change, some heavy metals in the sediment may be released into the water through desorption, dissolution, and redox reactions, causing secondary water pollution, damaging the ecological environment, and accumulating through the food chain to harm human health. Therefore, the safe disposal of heavy metal-contaminated sediment is particularly necessary.

[0003] Currently, there are two main methods for remediating pollutants in sediment, both domestically and internationally: in-situ remediation and ex-situ remediation. In-situ remediation refers to directly applying physical, chemical, and biological methods to adsorb, degrade, or solidify / stabilize pollutants in the sediment without dredging. Ex-situ fixation or treatment involves dredging the contaminated sediment and then treating it. In-situ treatment generally cannot fundamentally reduce the content of heavy metal pollutants in sediment and may cause significant damage to the aquatic environment. Ex-situ remediation methods have a significant impact on aquatic ecosystems, exacerbating the release of pollutants from the sediment in the short term, and the dredged sediment also poses problems of land occupation and secondary pollution. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to overcome the deficiencies and defects mentioned in the background art above, and to provide a foldable in-situ electrodynamic-phytoremediation device for heavy metal-contaminated sediments in rivers and lakes that is simple in structure and can effectively remediate heavy metal-contaminated sediments in rivers and lakes.

[0005] To solve the above-mentioned technical problems, the technical solution proposed by the present invention is: a foldable in-situ electrodynamic-phytoremediation device for heavy metal contaminated sediment in rivers and lakes, comprising: a horizontal frame; an insulating tube connected end to end and arranged horizontally; and two insulating tubes arranged opposite each other with symmetrically opened pivot holes in the middle.

[0006] The longitudinal frame includes two vertically arranged support tubes connected to the bottom of two insulating tubes, a first connector connected to the top of the two support tubes, and a second connector connected to the bottom of the two support tubes. The first connector has a first through hole and a second through hole arranged vertically, and the second connector has a third through hole. Each support tube is connected to two diagonal braces. The other ends of the two diagonal braces are detachably connected to the two ends of the same insulating tube. The longitudinal frame is made of insulating material.

[0007] A horizontal rotating shaft is inserted into the first through hole of the first connector, and the two ends of the horizontal rotating shaft are respectively connected to the rotating shaft holes of two insulating tubes, so that the horizontal frame can rotate around the horizontal rotating shaft.

[0008] Aquatic plant planting trays, set on a horizontal frame, are used to plant metal-rich emergent or submerged plants.

[0009] The cathode electrode rod is horizontally installed in the second through hole of the first connector;

[0010] The anode electrode rod is horizontally installed in the third through hole of the second connector; the cathode electrode rod and the anode electrode rod are connected to the negative and positive terminals of the power supply respectively by wires, and multiple through holes are provided on the wall surface where the second and third through holes are located.

[0011] In one embodiment, the two support tubes are telescopic tubes with adjustable length.

[0012] In one embodiment, the first connector is a double-hole tube, with a first through hole and a second through hole formed inside the double-hole tube.

[0013] In one embodiment, the bottom of the second connector is formed with an acute-angled tip.

[0014] In one embodiment, the ends of the two oppositely arranged insulating tubes are provided with limit holes, and the diagonal brace and the insulating tube are detachably connected by rivets and limit holes.

[0015] In one embodiment, the horizontal frame is a square frame.

[0016] In one embodiment, a diagonal brace mounting hole is provided at the midpoint of each support tube for mounting two diagonal braces.

[0017] Compared with existing technologies, the beneficial effects of this invention are as follows: The foldable in-situ electrodynamic-phytoremediation device for heavy metal-contaminated river and lake sediments combines electrodynamic remediation with phytoremediation technology. Utilizing horizontally positioned electrode rods within the heavy metal-contaminated sediment, the electric field can be controlled within the sediment layer, reducing the impact of overlying water on the remediation process. The anode electrode rod is located in the lower sediment layer; electrolysis reduces heavy metal ions in the sediment near the anode, facilitating the precipitation of heavy metals from the sediment. These ions then migrate to the shallower sediment layer under the influence of the electric field, allowing for absorption by aquatic plants in the planting tray. The low-voltage electric field promotes plant growth and facilitates the diffusion and transport of pollutants, overcoming the drawbacks of long phytoremediation cycles and limited remediation scope to the rhizosphere, while also mitigating the destructive effects of the electrodynamic process on soil structure. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 A schematic diagram of a foldable in-situ electro-phytoremediation device for heavy metal contaminated sediment in rivers and lakes, as one embodiment.

[0020] Figure 2 A schematic diagram of the structure of a foldable in-situ electro-phytoremediation device for heavy metal contaminated sediments in rivers and lakes after removing the aquatic plant planting tray, as one embodiment.

[0021] Figure 3 A schematic diagram of the longitudinal frame structure of a foldable in-situ electro-phytoremediation device for heavy metal contaminated sediments in rivers and lakes, as one embodiment.

[0022] Figure 4 A schematic diagram of the horizontal frame structure of a foldable in-situ electro-phytoremediation device for heavy metal contaminated sediments in rivers and lakes, as one embodiment.

[0023] Figure 5 A plan view of the remediation status of a foldable in-situ electro-phytoremediation device for heavy metal contaminated sediments in rivers and lakes, according to one embodiment.

[0024] Reference numerals: 1: Longitudinal frame, 2: Horizontal frame, 3: Horizontal pivot, 4: Diagonal brace, 5: Cathode electrode rod, 6: Anode electrode rod, 7: Wire, 8: Power supply, 9: Aquatic plant planting tray, 20: Insulating tube, 10: Support tube, 12: First connector, 14: Second connector, 1-2: Diagonal brace mounting hole, 2-1: Pivot hole, 2-2: Limiting hole. Detailed Implementation

[0025] To facilitate understanding of the present invention, the present invention will be described more fully and in detail below with reference to the accompanying drawings and preferred embodiments, but the scope of protection of the present invention is not limited to the following specific embodiments.

[0026] Unless otherwise defined, all technical terms used herein have the same meaning as commonly understood by those skilled in the art. The technical terms used herein are for the purpose of describing particular embodiments only and are not intended to limit the scope of the invention.

[0027] Unless otherwise specified, all raw materials, reagents, instruments and equipment used in this invention can be purchased from the market or prepared by existing methods.

[0028] Please see Figure 1-5 One embodiment of the foldable in-situ electrodynamic-phytoremediation device for heavy metal contaminated sediment in rivers and lakes mainly includes a longitudinal frame 1, a horizontal frame 2, a horizontal rotating shaft 3, a diagonal brace 4, a cathode electrode rod 5, an anode electrode rod 6, a wire 7, a power supply 8, and an aquatic plant planting tray 9. Specifically, the horizontal frame 2 includes an insulating tube 20 connected end to end and arranged horizontally; a rotating shaft hole 2-1 is symmetrically opened in the middle of two oppositely arranged insulating tubes 20. The longitudinal frame 1 includes two vertically arranged support tubes 10 respectively connected to the bottom of the two insulating tubes 20, a first connector 12 connected to the top of the two support tubes 10, and a second connector 14 connected to the bottom of the two support tubes. The first connector 12 has a first through hole and a second through hole arranged vertically, and the second connector 14 has a third through hole. Multiple perforations are provided on the wall surface where the second and third through holes are located. Each support tube 10 is connected to two diagonal braces 4; the other ends of the two diagonal braces 4 are detachably connected to the two ends of the same insulating tube 20, and the longitudinal frame 1 is made of insulating material. A horizontal rotating shaft 3 passes through the first through hole of the first connector 12, and the two ends of the horizontal rotating shaft 3 are respectively connected to the rotating shaft holes 2-1 of the two insulating tubes 20, allowing the horizontal frame 2 to rotate around the horizontal rotating shaft 3. An aquatic plant planting tray 9 is set on the horizontal frame 2 and is used to plant metal-rich emergent or submerged plants. The cathode electrode rod 5 is horizontally installed in the second through hole of the first connector 12. The anode electrode rod 6 is horizontally installed in the third through hole of the second connector 14; the cathode electrode rod 5 and the anode electrode rod 6 are connected to the negative and positive terminals of the power supply 8 respectively via wires 7.

[0029] Specifically, in one embodiment, the horizontal frame 2 is a square frame structure, with four insulating tubes 20 connected end to end to form a square frame. A pivot hole 2-1 is symmetrically opened at the midpoint of opposite insulating tubes 20 on the horizontal frame, and a limiting hole 2-2 is symmetrically opened at both ends of the insulating tubes 20.

[0030] Specifically, in one embodiment, the longitudinal frame 1 is made of insulating material and is also made of rigid material. Preferably, the longitudinal frame 1 is a square frame structure, specifically including two support pipes 10, a first connector 12 connected to the top of the two support pipes 10, and a second connector 14 connected to the bottom of the two support pipes 10. The support pipes 10, the first connector 12, and the second connector 14 are all hollow pipes. More preferably, the second connector 14 has an acute-angled tip at the bottom. The cross-section of the second connector 14 can be triangular or wedge-shaped, thus facilitating insertion into the heavy metal-contaminated sediment of rivers and lakes. Specifically, in one embodiment, the first connector 12 can be a figure-eight shaped double-hole pipe; in other embodiments, it can also be a square pipe with a first through hole and a second through hole. A diagonal brace mounting hole 1-2 is provided at the midpoint of the support pipe 10, and the part below the midpoint is a telescopic pipe with a limiting function to adjust the length of the support pipe 10, thus making it suitable for heavy metal-contaminated sediment of rivers and lakes at different depths.

[0031] Specifically, in one embodiment, the horizontal rotating shaft 3 passes through the first through hole of the first connecting member 12, and both ends of the horizontal rotating shaft 3 are connected to the rotating shaft holes 2-1 on the opposite insulating tubes 20 of the horizontal frame 2. The horizontal frame 2 can rotate around the horizontal rotating shaft 3. The foldable in-situ electrodynamic-phytoremediation device for heavy metal contaminated sediment in rivers and lakes is generally 1 to 2 meters in length, and the height is adjusted according to the depth of the sediment. During storage and transportation, the support tube 10 is retracted to its shortest distance, and the horizontal frame 2 is rotated to be on the same horizontal plane as the longitudinal frame 1, thereby folding the entire device and greatly reducing the floor space occupied.

[0032] Specifically, in one embodiment, there are four diagonal braces 4, with each support tube 10 connecting two diagonal braces 4. Specifically, a diagonal brace mounting hole 1-2 is provided at the midpoint of the support tube 10. One end of each of the two diagonal braces 4 is installed in the diagonal brace mounting hole 1-2 by a rivet, and the other end is riveted to the limiting holes 2-2 at both ends of an insulating tube 20 of the horizontal frame 2 by a rivet. After installation in the above manner, the diagonal braces 4 can restrict the rotation of the horizontal frame 2. That is to say, the foldable in-situ electrodynamic-phytoremediation device for heavy metal contaminated sediment in rivers and lakes is stable in its unfolded state.

[0033] Specifically, in one embodiment, the cathode electrode rod 5 is installed in the second through hole of the first connector 12. The anode electrode rod 6 is installed in the third through hole of the second connector 14. Since both the first connector 12 and the second connector 14 are horizontally arranged, the cathode electrode rod 5 and the anode electrode rod 6 are also horizontally arranged. The cathode electrode rod 5 and the anode electrode rod 6 are connected to the negative and positive terminals of the power supply 8 respectively via wires 7. The horizontal arrangement of the cathode electrode rod 5 and the anode electrode rod 6 can control the electric field within the bottom sediment layer, reducing the impact of the water covering the bottom sediment on the remediation process. The anode electrode rod 6 is located in the lower layer of the bottom sediment. Electrolysis can reduce the content of heavy metal ions near the anode, and then the ions migrate to the shallow bottom sediment layer near the cathode through the electric field, facilitating absorption by aquatic plants.

[0034] Specifically, in one embodiment, the aquatic plant planting tray 9 is connected to the horizontal frame 2. Emergent or submerged plants that accumulate heavy metals are planted in the aquatic plant planting tray 9 according to the type of heavy metal and the depth of the overlying water. Specifically, the aquatic plants can be reeds, cattails, calamus, hornwort, hydrangea, or myriophyllum, etc.

[0035] The method of using the foldable in-situ electrodynamic-phytoremediation device for heavy metal contaminated sediments in rivers and lakes according to one embodiment is as follows:

[0036] Before general use, the foldable in-situ electrodynamic-phytoremediation device for heavy metal contaminated river and lake sediments is in a folded state. At this time, the geometric center lines of the horizontal frame 2, diagonal braces 4, and longitudinal frame 1 are all located on the same plane, facilitating transportation. When the device arrives at its destination, it must first be unfolded before being placed on the contaminated sediment for in-situ remediation. The specific operation is as follows:

[0037] S10, Device Deployment: The horizontal frame 2 rotates around the horizontal pivot 3 until the horizontal frame 2 is perpendicular to the longitudinal frame 1; the diagonal bracing rod 4 is riveted to both ends of the insulating tube 20; an aquatic plant planting tray 9 is installed above the horizontal frame 2, and heavy metal enrichment emergent or submerged plants are planted in the aquatic plant planting tray 9 according to the type of heavy metals in the polluted sediment and the depth of the overlying water.

[0038] S20. Repair Operation: Select and adjust the length of the support rod 10 according to the depth of the bottom mud repair, and connect the wire 7 to the cathode electrode rod 5 and the anode electrode rod 6; insert the repair device in the unfolded state into the bottom mud to be repaired, and make the horizontal frame 2 flush with the mud-water interface; select a power supply 8 with a suitable voltage, connect the wire 7 to the power supply 8, and start the in-situ electric-phytoremediation.

[0039] The above are merely preferred embodiments of the present invention. It should be noted that the present invention is not limited to the above embodiments. For those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principle of the present invention should also be considered within the scope of protection of the present invention.

Claims

1. A foldable, in-situ electrodynamic-phytoremediation device for heavy metal-contaminated sediment in rivers and lakes, characterized in that, include: Horizontal frame; Including horizontally arranged insulating pipes connected end to end; Two insulating tubes positioned opposite each other have symmetrically spaced pivot holes in the middle. The longitudinal frame includes two vertically arranged support tubes connected to the bottoms of two oppositely arranged insulating tubes, a first connector connected to the tops of the two support tubes, and a second connector connected to the bottoms of the two support tubes. The first connector has a first through hole and a second through hole arranged vertically, and the second connector has a third through hole. Each support tube is connected to two diagonal braces. The other ends of the two diagonal braces are detachably connected to the two ends of the same insulating tube. The longitudinal frame is made of insulating material. A horizontal rotating shaft is inserted into the first through hole of the first connector, and the two ends of the horizontal rotating shaft are respectively connected to the rotating shaft holes of two insulating tubes, so that the horizontal frame can rotate around the horizontal rotating shaft. Aquatic plant planting trays, set on a horizontal frame, are used to plant metal-rich emergent or submerged plants. The cathode electrode rod is horizontally installed in the second through hole of the first connector; The anode electrode rod is horizontally installed in the third through hole of the second connector; the cathode electrode rod and the anode electrode rod are connected to the negative and positive terminals of the power supply respectively by wires, and multiple through holes are provided on the wall surface where the second and third through holes are located.

2. The foldable in-situ electrodynamic-phytoremediation device for heavy metal contaminated sediments in rivers and lakes according to claim 1, characterized in that, The two support pipes are telescopic pipes with adjustable length.

3. The foldable in-situ electrodynamic-phytoremediation device for heavy metal contaminated sediments in rivers and lakes according to claim 1, characterized in that, The first connector is a double-hole tube, with a first through hole and a second through hole formed inside the double-hole tube.

4. The foldable in-situ electrodynamic-phytoremediation device for heavy metal contaminated sediments in rivers and lakes according to claim 1, characterized in that, The bottom of the second connector has an acute-angled tip.

5. The foldable in-situ electrodynamic-phytoremediation device for heavy metal contaminated sediments in rivers and lakes according to claim 1, characterized in that, The ends of the two oppositely arranged insulating tubes are provided with limit holes, and the diagonal brace and the insulating tube are detachably connected by rivets and limit holes.

6. The foldable in-situ electrodynamic-phytoremediation device for heavy metal contaminated sediments in rivers and lakes according to claim 1, characterized in that, The horizontal frame is a square frame.

7. The foldable in-situ electro-phytoremediation device for heavy metal contaminated sediment of river and lake according to claim 1, characterized in that, Each support tube has a diagonal brace mounting hole at its midpoint for mounting two diagonal braces.

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