Foldable device for in-situ electric-phytoremediation of river and lake heavy metal polluted bottom mud

Abstract

The invention belongs to the technical field of river and lake sediment remediation, and discloses a foldable device for in-situ electric-phytoremediation of river and lake heavy metal polluted sediment. Comprising a horizontally arranged insulating tube; the longitudinal frame comprises two supporting pipes, a first connecting piece and a second connecting piece, the two supporting pipes are vertically arranged and connected to the bottoms of the two insulating pipes respectively, a first through hole and a second through hole which are vertically formed are formed in the first connecting piece, a third through hole is formed in the second connecting piece, and two inclined supporting rods are connected to each supporting pipe; the two inclined supporting rods are detachably connected to the two ends of the same insulating tube respectively, and the longitudinal frame is made of insulating materials. The horizontal rotating shaft is arranged in the first through hole of the first connecting piece in a penetrating manner; the aquatic plant planting plate is arranged on the horizontal frame; the cathode electrode stem and the anode electrode stem are horizontally mounted in a second through hole and a third through hole which are provided with a plurality of through holes in the wall surface respectively; and the anode and the cathode of the power supply are respectively connected through wires.

Description

Technical Field

[0001] The present invention belongs to the technology of river and lake sediment remediation, and particularly relates to a device for in-situ electro-plant remediation of heavy metal contaminated sediments in rivers and lakes. Background Art

[0002] Heavy metals in water bodies are enriched in the surface sediments of water bodies through adsorption, complexation, precipitation and other processes. When environmental conditions change, some heavy metals in the sediments may be released into the water body through desorption, dissolution, redox and other processes, causing secondary pollution of the water body, damaging the ecological environment, and being harmful to human health through food chain enrichment. Therefore, it is particularly necessary to safely dispose of heavy metal contaminated sediments.

[0003] Currently, there are mainly two methods for remediating pollutants in sediments at home and abroad, namely in-situ remediation and ex-situ remediation. In-situ remediation refers to directly using physical, chemical, biological and other methods to adsorb, degrade or solidify / stabilize pollutants in the contaminated sediments without dredging; ex-situ fixation or treatment refers to dredging the contaminated sediments and then treating them. In general, in-situ treatment cannot fundamentally reduce the content of heavy metal pollutants in the sediments, and may also cause great damage to the water environment; the ex-situ remediation method has a greater impact on the aquatic ecosystem, will exacerbate the release of pollutants in the sediments in the short term, and there are also problems of land occupation and secondary pollution for the excavated sediments. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to overcome the above-mentioned deficiencies and defects in the background art, and provide a foldable device for in-situ electro-plant remediation of heavy metal contaminated sediments in rivers and lakes with a simple structure and capable of effectively remediating heavy metal contaminated sediments in rivers and lakes.

[0005] To solve the above technical problem, the technical solution proposed by the present invention is: a foldable device for in-situ electro-plant remediation of heavy metal contaminated sediments in rivers and lakes, comprising: a horizontal frame; including insulating pipes that are horizontally arranged and connected end to end; shaft holes are symmetrically opened in the middle of two relatively arranged insulating pipes; a longitudinal frame, including two support pipes that are vertically arranged and respectively connected to the bottoms of the two insulating pipes, a first connecting member connected to the tops of the two support pipes, and a second connecting member connected to the bottoms of the two support pipes. The first connecting member is provided with a first through hole and a second through hole arranged up and down, and a third through hole is opened in the second connecting member. Two diagonal braces are connected to each support pipe; and the other ends of the two diagonal braces are respectively detachably connected to the two ends of the same insulating pipe. The longitudinal frame is made of insulating material; a horizontal rotating shaft; passing through the first through hole of the first connecting member, and the two ends of the horizontal rotating shaft are respectively connected to the shaft holes of the two insulating pipes, and the horizontal frame can rotate around the horizontal rotating shaft; An aquatic plant planting tray is provided on a horizontal frame for planting metal-enriched emergent plants or submerged plants. A cathode electrode rod is horizontally installed in the second through-hole of the first connecting member. An anode electrode rod is horizontally installed in the third through-hole of the second connecting member. The cathode electrode rod and the anode electrode rod are respectively connected to the negative and positive poles of a power supply through wires, and a plurality of perforations are provided on the wall surfaces where the second through-hole and the third through-hole are located.

[0006] In one embodiment, the two support tubes are telescopic tubes with adjustable lengths.

[0007] In one embodiment, the first connecting member is a double-hole tube, and a first through-hole and a second through-hole are formed inside the double-hole tube.

[0008] In one embodiment, the bottom of the second connecting member forms an acute tip.

[0009] In one embodiment, limiting holes are provided at the ends of the two oppositely arranged insulating tubes, and the diagonal brace and the insulating tube are detachably connected through the cooperation of rivets and the limiting holes.

[0010] In one embodiment, the horizontal frame is a square frame.

[0011] In one embodiment, diagonal brace mounting holes are provided at the midpoints of each support tube for mounting two diagonal braces.

[0012] Compared with the prior art, the beneficial effects of the present invention are as follows: The foldable in-situ electro-plant remediation device for heavy metal contaminated sediment in rivers and lakes combines phytoremediation technology during the electroremediation process of heavy metal contaminated sediment in the bottom mud. By using electrode rods horizontally arranged in the heavy metal contaminated sediment of rivers and lakes, the electric field can be controlled within the bottom mud layer, reducing the impact of the overlying water on the remediation process. The anode electrode rod is located in the lower layer of the bottom mud. The electrolysis effect can reduce the heavy metal ions in the bottom mud near the anode, facilitating the precipitation of heavy metals in the bottom mud, and then migrating to the shallow layer of the bottom mud through the action of the electric field, so as to be absorbed by the aquatic plants in the aquatic plant planting tray. With the effects of promoting plant growth and promoting the diffusion and transportation of pollutants by the low-voltage electric field, it can not only solve the disadvantages of long phytoremediation cycle and limited remediation range within the rhizosphere, but also alleviate the damage to the soil structure during the electroremediation process. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for describing the embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0014] Figure 1 Schematic structural diagram of a foldable in-situ electro-phyto-remediation device for heavy metal contaminated sediment in rivers and lakes in one embodiment; Figure 2 Schematic structural diagram of the foldable in-situ electro-phyto-remediation device for heavy metal contaminated sediment in rivers and lakes in one embodiment after removing the aquatic plant planting tray; Figure 3 Schematic longitudinal frame structure diagram of the foldable in-situ electro-phyto-remediation device for heavy metal contaminated sediment in rivers and lakes in one embodiment; Figure 4 Schematic horizontal frame structure diagram of the foldable in-situ electro-phyto-remediation device for heavy metal contaminated sediment in rivers and lakes in one embodiment; Figure 5 Plan view of the foldable in-situ electro-phyto-remediation device for heavy metal contaminated sediment in rivers and lakes in one embodiment in the remediation state.

[0015] Reference numerals: 1: longitudinal frame, 2: horizontal frame, 3: horizontal rotating shaft, 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: rotating shaft hole, 2-2: limiting hole. Detailed implementation manners

[0016] For the convenience of understanding the present invention, the present invention will be described more comprehensively and meticulously below in conjunction with the accompanying drawings of the specification and preferred embodiments, but the protection scope of the present invention is not limited to the following specific embodiments.

[0017] Unless otherwise defined, all professional terms used below have the same meaning as commonly understood by those skilled in the art. The professional terms used herein are only for the purpose of describing specific embodiments and are not intended to limit the protection scope of the present invention.

[0018] Unless otherwise specifically stated, various raw materials, reagents, instruments, and equipment used in the present invention can be obtained through the market or prepared by existing methods.

[0019] Please refer to Figures 1-5, The device for collapsible in-situ electro-phyto-remediation of heavy metal contaminated sediments in rivers and lakes in one embodiment mainly includes a longitudinal frame 1, a horizontal frame 2, a horizontal rotating shaft 3, diagonal braces 4, a cathode electrode rod 5, an anode electrode rod 6, a wire 7, a power source 8 and an aquatic plant planting tray 9. Specifically, the horizontal frame 2 includes insulating tubes 20 that are connected end to end and arranged horizontally; rotating shaft holes 2-1 are symmetrically opened in the middle of two relatively arranged insulating tubes 20. The longitudinal frame 1 includes two support tubes 10 that are vertically arranged and are respectively connected to the bottoms of the two insulating tubes 20, a first connecting member 12 connected to the tops of the two support tubes 10, and a second connecting member 14 connected to the bottoms of the two support tubes. The first connecting member 12 is provided with a first through hole and a second through hole arranged vertically, and a third through hole is opened in the second connecting member 14. A plurality of through holes are provided on the wall surfaces where the second through hole and the third through hole are located. Two diagonal braces 4 are connected to each support tube 10; and the other ends of the two diagonal braces 4 are respectively detachably connected to both ends of the same insulating tube 20. The longitudinal frame 1 is made of an insulating material. 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 respectively connected to the rotating shaft holes 2-1 of the two insulating tubes 20. The horizontal frame 2 can rotate around the horizontal rotating shaft 3. The aquatic plant planting tray 9 is arranged on the horizontal frame 2 and is used for planting metal-enriched emergent plants or submerged plants. The cathode electrode rod 5 is horizontally installed in the second through hole of the first connecting member 12. The anode electrode rod 6 is horizontally installed in the third through hole of the second connecting member 14; the cathode electrode rod 5 and the anode electrode rod 6 are respectively connected to the negative electrode and the positive electrode of the power source 8 through the wire 7.

[0020] Specifically, in one embodiment, the horizontal frame 2 is a square frame structure, and four insulating tubes 20 are connected end to end to form a square frame. Rotating shaft holes 2-1 are symmetrically opened at the midpoints of the relatively arranged insulating tubes 20 of the horizontal frame, and limiting holes 2-2 are symmetrically opened at both ends of the insulating tubes 20.

[0021] Specifically, in one embodiment, the longitudinal frame 1 is made of insulating material and is of rigid material. Preferably, the longitudinal frame 1 is of a square frame structure, specifically including two support pipes 10, a first connecting piece 12 connected to the tops of the two support pipes 10, and a second connecting piece 14 connected to the bottoms of the two support pipes 10. The support pipes 10, the first connecting piece 12, and the second connecting piece 14 are all hollow pipes. More preferably, the second connecting piece 14 forms an acute tip at the bottom. The cross-section of the second connecting piece 14 can be triangular or wedge-shaped, so that it can be more conveniently inserted into the heavy metal polluted sediment at the bottom of rivers and lakes. Specifically, in one embodiment, the first connecting piece 12 can be a double-hole pipe in the shape of an "8". In other embodiments, it can also be a square pipe provided with a first through hole and a second through hole. An inclined strut 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, so that it can be applicable to heavy metal polluted sediment at different depths at the bottom of rivers and lakes.

[0022] Specifically, in one embodiment, the horizontal rotating shaft 3 passes through the first through hole of the first connecting piece 12, and both ends of the horizontal rotating shaft 3 are respectively connected to the rotating shaft holes 2-1 on the opposite insulating pipes 20 of the horizontal frame 2. The horizontal frame 2 can rotate around the horizontal rotating shaft 3. The device for in-situ electro-phyto-remediation of heavy metal polluted sediment in rivers and lakes that can be folded is generally 1 to 2 meters in length, and the height is adjusted according to the different depths of the sediment. During storage and transportation, the support pipe 10 is contracted to the shortest distance, and the horizontal frame 2 is rotated to the same horizontal plane as the longitudinal frame 1, so as to fold the whole device, greatly reducing the floor area.

[0023] Specifically, in one embodiment, the number of inclined struts 4 is four, and each support pipe 10 is connected to two inclined struts 4. Specifically, an inclined strut mounting hole 1-2 is provided at the midpoint of the support pipe 10. One ends of the two inclined struts 4 are installed in the inclined strut mounting hole 1-2 by rivets, and the other ends are riveted to the limiting holes 2-2 at both ends of an insulating pipe 20 of the horizontal frame 2 by rivets. After being installed in the above manner, the inclined struts 4 can limit the rotation of the horizontal frame 2, that is to say, the device for in-situ electro-phyto-remediation of heavy metal polluted sediment in rivers and lakes that can be folded is stable in the unfolded state.

[0024] Specifically, in one embodiment, the cathode electrode rod 5 is installed in the second through hole of the first connecting member 12. The anode electrode rod 6 is installed in the third through hole of the second connecting member 14. Since both the first connecting member 12 and the second connecting member 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 respectively connected to the negative and positive poles of the power supply 8 through wires 7. The horizontal arrangement of the cathode electrode rod 5 and the anode electrode rod 6 can control the electric field within the sediment layer and reduce the influence of the overlying water of the sediment on the remediation process. Among them, the anode electrode rod 6 is located in the lower layer of the sediment. The electrolysis effect can reduce the content of heavy metal ions near the anode, and then migrate to the shallow layer of the sediment near the cathode through the action of the electric field, which is convenient for aquatic plants to absorb.

[0025] Specifically, in one embodiment, the aquatic plant planting tray 9 is connected to the horizontal frame 2. In the aquatic plant planting tray 9, heavy metal-enriched emergent plants or submerged plants are planted according to the types of heavy metals and the depth of the overlying water. Specifically, the aquatic plants can be reeds, cattails, calamus, hornworts, hydrilla verticillata or myriophyllum verticillatum, etc.

[0026] The usage method of the foldable in-situ electro-phyto-remediation device for heavy metal contaminated sediment in rivers and lakes in one embodiment is as follows: Generally, before use, the foldable in-situ electro-phyto-remediation device for heavy metal contaminated sediment in rivers and lakes is in a folded state. At this time, the geometric centerlines of the horizontal frame 2, the diagonal strut 4 and the longitudinal frame 1 are all located in the same plane, which is convenient for transportation. When the foldable in-situ electro-phyto-remediation device for heavy metal contaminated sediment in rivers and lakes is transported to the destination, first, the foldable in-situ electro-phyto-remediation device for heavy metal contaminated sediment in rivers and lakes needs to be unfolded, and then the device is placed in the heavy metal contaminated sediment in rivers and lakes for in-situ remediation. The specific operations are as follows: S10. Device unfolding: The horizontal frame 2 rotates around the horizontal rotating shaft 3 until the horizontal frame 2 is perpendicular to the longitudinal frame 1; the diagonal strut 4 is riveted to both ends of the insulating tube 20; the aquatic plant planting tray 9 is installed above the horizontal frame 2, and heavy metal-enriched emergent plants or submerged plants are planted in the aquatic plant planting tray 9 according to the types of heavy metals in the contaminated sediment and the depth of the overlying water.

[0027] S20. Remediation operation: Select and adjust the length of the support rod 10 according to the sediment remediation depth, and connect the wire 7 to the cathode electrode rod 5 and the anode electrode rod 6; insert the unfolded remediation device into the remediation sediment, and make the horizontal frame 2 flush with the mud-water interface; select a power supply 8 with an appropriate voltage, connect the wire 7 to the power supply 8, and start the in-situ electro-phyto-remediation.

[0028] The above are only the preferred embodiments of the present invention. It should be noted that the present invention is not limited to the above embodiments. For those of ordinary skill in the art of this technology, without departing from the principle of the present invention, several improvements and refinements can be made. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention should also be regarded as the protection scope of the present invention.

Claims

1. A collapsible in-situ electro-phytoremediation device for heavy metal contaminated sediment in rivers and lakes, characterized in that, Comprising: A horizontal frame; Including insulating tubes that are connected end to end and arranged horizontally; Rotating shaft holes are symmetrically formed in the middle of two relatively arranged insulating tubes; A longitudinal frame, including two support tubes that are vertically arranged and respectively connected to the bottoms of the two insulating tubes, a first connecting member connected to the tops of the two support tubes, and a second connecting member connected to the bottoms of the two support tubes. The first connecting member is provided with a first through hole and a second through hole that are arranged vertically. A third through hole is formed in the second connecting member. Two diagonal braces are connected to each support tube; and the other ends of the two diagonal braces are respectively detachably connected to the two ends of the same insulating tube. The longitudinal frame is made of insulating material; A horizontal rotating shaft; It is inserted into the first through hole of the first connecting member, and the two ends of the horizontal rotating shaft are respectively connected to the rotating shaft holes of the two insulating tubes. The horizontal frame can rotate around the horizontal rotating shaft; An aquatic plant planting tray, arranged on the horizontal frame, for planting metal-enriched emergent plants or submerged plants; A cathode electrode rod, horizontally installed in the second through hole of the first connecting member; An anode electrode rod, horizontally installed in the third through hole of the second connecting member; The cathode electrode rod and the anode electrode rod are respectively connected to the negative and positive electrodes of the power supply through wires. A plurality of through holes are provided on the wall surfaces where the second through hole and the third through hole are located.

2. The collapsible in-situ electro-phytoremediation device for heavy metal contaminated sediment in rivers and lakes according to claim 1, characterized in that, The two support tubes are telescopic tubes with adjustable lengths.

3. The device for in-situ electro-phyto-remediation of heavy metal contaminated sediment in rivers and lakes according to claim 1, wherein The first connecting member is a double-hole tube, and a first through hole and a second through hole are formed inside the double-hole tube.

4. The device for collapsible in-situ electro-phytoremediation of heavy metal contaminated sediment in rivers and lakes according to claim 1, wherein The bottom of the second connecting member forms an acute tip.

5. The device for collapsible in-situ electro-phyto-remediation of heavy metal contaminated sediment in rivers and lakes according to claim 1, characterized in that, Limit holes are formed at the ends of the two relatively arranged insulating tubes, and the diagonal braces and the insulating tubes are detachably connected through the cooperation of rivets and the limit holes.

6. The device for collapsible in-situ electro-phyto-remediation of heavy metal contaminated sediment in rivers and lakes according to claim 1, characterized in that, The horizontal frame is a square frame.

7. The device for collapsible in-situ electro-phyto-remediation of heavy metal contaminated sediment in rivers and lakes according to claim 1, characterized in that, Diagonal brace mounting holes are formed at the midpoints of each support tube for mounting two diagonal braces.

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