Heavy metal contaminated soil remediation and treatment equipment and method thereof

Abstract

The invention belongs to the technical field of soil remediation, and particularly discloses heavy metal contaminated soil remediation treatment equipment and a method thereof.The remediation treatment equipment comprises a microbial agent preparation unit and an in-situ injection unit, the in-situ injection unit is provided with an embedded base body, a drainage branch pipe, a guide rail frame and a covering pad, and the embedded base body is provided with a temporary storage cavity; the guide rail frame forms a warm-keeping area through coaxial inner and outer ring guide rails, and the moving rod is arranged between the guide rails in a sliding mode and connected with the covering pad. The microbial inoculum is uniformly injected into the soil through the drainage branch pipes, meanwhile, the coverage rate of the covering pad is adjusted by sliding the moving rod, the soil temperature of a microbial inoculum acting area is accurately regulated and controlled, a suitable growth environment is created for functional microorganisms, the microbial activity and the soil remediation efficiency are improved, the equipment structure is reasonable, operation is convenient, the coverage rate is flexible to adjust, and the application range is wide. And the method is suitable for different soil temperature environments, green, environment-friendly, free of secondary pollution and good in remediation effect.

Description

Technical Field

[0001] This invention belongs to the field of soil remediation technology, and specifically relates to a device and method for remediating heavy metal contaminated soil. Background Technology

[0002] With the continuous development of human activities such as industrial production and agricultural planting, soil heavy metal pollution has become an increasingly prominent problem. It not only damages the soil ecological structure and reduces soil fertility, but also threatens human health through bioaccumulation in the food chain. Therefore, soil heavy metal pollution remediation has become an important research direction and urgent need in the field of ecological and environmental protection. Among the many soil heavy metal pollution remediation technologies, microbial remediation technology, with its advantages of being environmentally friendly, causing no secondary pollution, being low-cost, and synergistically improving the soil microecology, has become one of the core technologies in the field of green and sustainable remediation, and is widely used in the treatment of large-scale soils contaminated with low to medium concentrations of heavy metals.

[0003] The core principle of microbial remediation technology is to utilize the adsorption, precipitation, redox, methylation, and demethylation processes of functional microorganisms to alter the form of heavy metals in the soil, reducing their bioavailability and mobility, thereby achieving soil purification and remediation. Current microbial remediation equipment mostly employs in-situ injection technology, which involves directly injecting functional microorganisms into the ground without disturbing the contaminated soil. This activates or enhances the microorganisms' degradation / fixation of pollutants, achieving in-situ remediation. However, existing microbial remediation equipment exhibits low conversion efficiency after microorganism injection, resulting in unsatisfactory actual remediation effects.

[0004] For example, Chinese patent application CN119259674A proposes an intelligent underground remediation device for microbial remediation of heavy metal contaminated soil. This device only discharges the remediation medium into the soil to achieve remediation, without considering the internal temperature environment of the soil, resulting in low actual remediation efficiency. Similarly, Chinese patent application CN221515609U discloses an underground application device for bacterial solutions, which remediates heavy metal contaminated soil by injecting the treatment solution underground. This also fails to consider the internal temperature environment of the soil, leading to low actual remediation efficiency. Summary of the Invention

[0005] To address the aforementioned problems, the purpose of this invention is to provide a heavy metal contaminated soil remediation equipment and method that can regulate the soil temperature in the area where the microbial agent acts, create a suitable growth and metabolic environment for functional microorganisms, enhance the remediation activity of microorganisms, and thus improve the remediation efficiency and effectiveness of heavy metal contaminated soil.

[0006] The technical solution of the present invention is: a heavy metal contaminated soil remediation and treatment device, comprising a microbial agent preparation unit and an in-situ injection unit, wherein the microbial agent preparation unit is connected to the in-situ injection unit, the microbial agent preparation unit is used to prepare microbial agents, and the in-situ injection unit injects them into the heavy metal contaminated soil to be remediated; the in-situ injection unit comprises a pre-embedded substrate, a drainage branch pipe, a guide rail frame and a covering pad.

[0007] The bottom of the pre-buried substrate is buried in the heavy metal contaminated soil to be remediated. The interior of the pre-buried substrate has a temporary storage cavity, which is connected to the microbial agent preparation unit.

[0008] There are multiple drainage branches, which are arranged around the pre-buried substrate. All drainage branches are buried in the heavy metal contaminated soil to be remediated. The inlet end of the drainage branch is connected to the temporary storage chamber, and the other end of the drainage branch is closed. Multiple liquid outlets are opened on its side wall. The liquid outlets are used as outlets to discharge microbial agents.

[0009] The guide rail frame includes an inner ring guide rail, an outer ring guide rail, and movable rods. The inner ring guide rail is fixed to the outer wall of the pre-embedded substrate; the outer ring guide rail is coaxially arranged with the inner ring guide rail, and the space between the outer ring guide rail and the inner ring guide rail forms an insulation zone; there are multiple movable rods, which are evenly distributed in the insulation zone, and each movable rod has a slider at both ends, which slides on the inner ring guide rail and the outer ring guide rail respectively.

[0010] The covering pad is made of a flexible pad body. The covering pad has a circular structure and at least one opening in the radial direction. The ends of the covering pad located on both sides of the opening are fixed to two adjacent moving rods. The bottom surface of the covering pad is fixed to other moving rods. By sliding the moving rods, the ends of the covering pad can be moved to adjust the size of the opening, thereby adjusting the coverage of the covering pad above the insulation area.

[0011] Furthermore, the inner ring guide rail includes multiple inner arc tracks connected in sequence, and the outer ring guide rail includes multiple outer ring tracks connected in sequence. Each outer ring track corresponds one-to-one with a single inner arc track and is fixed by a fixing rod. There are two sets of fixing rods, each set used to fix both ends of the inner arc track and the outer ring track. The two sets of fixing rods, along with the inner arc track and the outer ring track, form a fan-shaped structure. At least one movable rod is distributed on each fan-shaped structure, and both ends of the movable rod are slidably positioned within the inner arc track and the outer ring track respectively via sliders.

[0012] Furthermore, the covering pad includes multiple fan-shaped pads, which are distributed one-to-one on multiple fan-shaped structures, and the opposite ends of two adjacent fan-shaped pads form the opening.

[0013] Furthermore, a movable rod is correspondingly distributed on the fan-shaped structure, one end of the fan-shaped pad is fixed to any fixed rod, and the other end is fixed to the movable rod inside the fan-shaped structure.

[0014] Furthermore, multiple movable rods are distributed on the fan-shaped structure, and the two ends of the fan-shaped pad are respectively fixed to two movable rods located at the edge of the fan-shaped structure, while the middle section of the fan-shaped pad is uniformly fixed to other movable rods.

[0015] Furthermore, both the inner arc track and the outer ring track are provided with teeth, and the slider is rotatably provided with gears that mesh with the teeth. Each slider is also provided with a drive motor connected to the gears for driving the gears to rotate.

[0016] Furthermore, the remediation equipment also includes a temperature control unit, which comprises a temperature sensing module and a control module. The temperature sensing module is installed at the bottom of the pre-buried substrate to collect temperature signals from the soil near the bottom of the pre-buried substrate; the control module is electrically connected to the temperature sensing module and the drive motor, respectively, to receive temperature signals and control the operation of the drive motor.

[0017] Furthermore, there are multiple sets of in-situ injection units, each set corresponding to a microbial agent preparation unit, and the temporary storage chamber of each set of in-situ injection units is connected to the microbial agent preparation unit.

[0018] Furthermore, the covering pad includes an insulation blanket and a straw layer covering the insulation blanket. The straw layer includes straw bundles and a woven rope net for binding the straw bundles. The length direction of the straw bundles is consistent with the length direction of the moving rod.

[0019] A method for remediating heavy metal contaminated soil, comprising the following steps, using the aforementioned remediation equipment to remediate heavy metal contaminated soil: Excavate a foundation pit that is consistent with the bottom of the pre-embedded substrate, and dig drip troughs around the foundation pit that correspond to the number and location of the drainage branch pipes.

[0020] Place the pre-embedded substrate in the foundation pit and place the drainage branch pipes one by one in the drip trough; backfill the soil so that the bottom of the pre-embedded substrate and the drainage branch pipes are buried in the soil.

[0021] The microbial agent preparation unit is connected to the temporary storage chamber, and the microbial agent is injected into the temporary storage chamber; the sliding rod adjusts the covering pad to cover the warm area.

[0022] Compared with the prior art, the beneficial effects of the present invention are as follows: This invention utilizes a coaxial inner and outer ring guide rail to form a heat-insulating zone, coupled with an adjustable circular flexible covering pad. This enables controllable heat and moisture retention in the surface soil area where microbial agents are injected, maintaining stable temperatures in the shallow soil layer and around the drainage branch pipes. This provides a suitable temperature environment for the growth, reproduction, and heavy metal fixation / transformation of functional microorganisms, significantly improving the efficiency of microbial adsorption, precipitation, and oxidation-reduction of heavy metals. This fundamentally solves the shortcomings of existing equipment in terms of low remediation and transformation efficiency and poor results.

[0023] The device utilizes a sliding rod positioned between the inner and outer ring guide rails to open and close a radially open annular covering pad. This allows for real-time adjustment of the covering area and opening size based on ambient temperature, seasonal changes, and the microbial growth stage. This effectively prevents heat loss due to insufficient coverage, enabling precise control of the insulation effect and enhancing the adaptability and stability of microbial remediation. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the overall structure of the in-situ injection unit of the present invention; Figure 2 This is a partial top view of the guide rail frame of the present invention; Figure 3 This is a cross-sectional view of the in-situ injection unit of the present invention; Figure 4 This is a partial top view of the guide rail frame of the present invention; Figure 5 This is a cross-sectional view of the covering pad of the present invention; Figure 6 This is a schematic diagram of the structure of Embodiment 3 of the present invention.

[0025] Among them, 1-embedded base, 10-temporary storage cavity, 2-drainage branch pipe, 3-guide rail frame, 31-inner ring guide rail, 310-inner arc track, 32-outer ring guide rail, 320-outer ring track, 33-moving rod, 330-slider, 34-fixed rod, 4-covering pad, 40-fan-shaped pad, 41-insulation blanket, 42-straw layer, 5-temperature control unit, 51-temperature sensing module, 52-control module. Detailed Implementation

[0026] The following is combined with Figures 1 to 6 The specific embodiments of the present invention will be described in detail below. In the description of the present invention, it should be understood that the terms "center," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings and are only for the convenience of describing the present invention and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the present invention.

[0027] The terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature; in the description of this invention, unless otherwise stated, "a plurality of" means two or more.

[0028] The growth, metabolism, and remediation activity of microorganisms are strictly dependent on soil environmental conditions. Among them, temperature is a key environmental factor affecting microbial activity. Most functional microorganisms used for the remediation of heavy metal contaminated soil have an optimal temperature range of 25℃ to 30℃ for growth and metabolism. Within this temperature range, the microorganisms have the strongest activity and the remediation efficiency is optimal. When the soil temperature deviates from this optimal range, the growth and reproduction of microorganisms will be significantly inhibited, the metabolic rate will decrease, and the efficiency of heavy metal transformation will be reduced, which will seriously affect the soil remediation effect and even lead to the failure of the remediation process.

[0029] Current microbial remediation equipment does not consider the impact of temperature and environmental factors on microbial growth, resulting in low conversion efficiency.

[0030] It should be noted that the circuit connections involved in this invention all adopt conventional circuit connection methods and do not involve any innovation.

[0031] Example 1 A heavy metal contaminated soil remediation device includes a microbial agent preparation unit and an in-situ injection unit. The microbial agent preparation unit is connected to the in-situ injection unit. The microbial agent preparation unit is used to prepare microbial agents, which are then injected into the heavy metal contaminated soil to be remediated through the in-situ injection unit. Figure 1 As shown, the in-situ injection unit includes a pre-embedded substrate 1, a drainage branch pipe 2, a guide rail frame 3, and a covering pad 4.

[0032] The bottom of the pre-embedded substrate 1 is buried in the heavy metal contaminated soil to be remediated. The interior of the pre-embedded substrate 1 has a temporary storage cavity 10, which is connected to the microbial agent preparation unit. It should be noted that: in this embodiment, the pre-embedded substrate 1 is a variable-diameter cylindrical structure closed at both ends, with the bottom diameter being smaller than the top diameter. An equipment cavity is also provided at the lower end of the temporary storage cavity 10, which is used to house the temperature control unit 5. Sixteen interfaces, each communicating with the temporary storage cavity 10, are evenly distributed circumferentially on the side wall of the pre-embedded substrate 1 on the lower surface of the temporary storage cavity 10.

[0033] There are multiple drainage branch pipes 2, which are arranged around the pre-buried substrate 1. All drainage branch pipes 2 are buried in the heavy metal contaminated soil to be remediated. The inlet end of each drainage branch pipe 2 is connected to the temporary storage chamber 10, and the other end is closed. Multiple outlets are provided on its side wall, serving as outlets for discharging microbial agents. It should be noted that in this embodiment, there are 16 drainage branch pipes 2, each connected to one of 16 interfaces.

[0034] like Figure 2 , Figure 3 As shown, the guide rail frame 3 includes an inner ring guide rail 31, an outer ring guide rail 32, and moving rods 33. The inner ring guide rail 31 is fixed to the outer wall of the pre-embedded base 1; the outer ring guide rail 32 is coaxially arranged with the inner ring guide rail 31, and the outer ring guide rail 32 and the inner ring guide rail 31 form a heat preservation area; there are multiple moving rods 33, which are evenly distributed in the heat preservation area. Each moving rod 33 has a slider 330 at both ends, and the sliders 330 are slidably mounted on the inner ring guide rail 31 and the outer ring guide rail 32 respectively.

[0035] The covering pad 4 is a flexible pad. The covering pad 4 has a circular structure and at least one opening in the radial direction. The ends of the covering pad 4 located on both sides of the opening are fixed to two adjacent moving rods 33. The bottom surface of the covering pad 4 is fixed to other moving rods 33. By sliding the moving rods 33, the end of the covering pad 4 can be moved to adjust the size of the opening and thus adjust the coverage of the covering pad 4 above the heat preservation area.

[0036] The equipment forms a warming zone by enclosing an inner ring guide rail 31 and an outer ring guide rail 32. With the help of a movable rod 33 that can slide along the guide rail to adjust the coverage of the covering pad 4, it can specifically regulate the soil temperature in the core action area of ​​the microbial agent, stabilizing the temperature within the suitable growth and metabolism range of 25℃~30℃ for the remediation microorganisms. This solves the problem of traditional equipment ignoring the influence of temperature and inhibiting the activity of microorganisms, effectively improving the efficiency of heavy metal transformation and fundamentally improving the soil remediation effect.

[0037] Multiple drainage branch pipes 2 are arranged in a ring around the pre-embedded substrate 1 and are all buried in the soil. The inlet end is connected to the temporary storage chamber 10 inside the pre-embedded substrate 1, and multiple sets of liquid outlets are opened on the side wall. This allows the microbial agent to be buffered by the temporary storage chamber 10 and then evenly diffused to all areas of the soil through the drainage branch pipes 2, avoiding excessively high or low concentrations of the agent in some areas. This achieves comprehensive remediation of heavy metal contaminated soil and improves the uniformity and thoroughness of the remediation.

[0038] The coverage pad 4 achieves stepless adjustment of coverage by sliding the movable rod 33. The sliders 330 at both ends of the movable rod 33 precisely cooperate with the inner ring guide rail 31 and the outer ring guide rail 32. The split structure of the guide rail frame 3 supports zoned control. It can adjust the degree of heat preservation / heat dissipation according to the soil temperature differences in different seasons and regions, as well as the temperature changes in different areas of the soil. It is suitable for a variety of remediation scenarios and has strong versatility.

[0039] The movable rod 33 slides with the inner ring guide rail 31 and the outer ring guide rail 32 through the slider 330, ensuring smooth transmission and guaranteeing that the unfolding / retraction of the covering pad 4 is smooth and without wrinkles or accumulation, thus improving the uniformity of temperature control. The buried design of the pre-embedded substrate 1 and the drainage branch pipe 2 has a high degree of soil adhesion. The addition of microbial agent and the temperature control operation are independent yet coordinated. The overall installation and operation process of the equipment is simple, which is convenient for on-site construction and operation.

[0040] The covering mat 4 has a flexible mat structure that fits the annular insulation area of ​​the guide rail frame 3, allowing it to closely adhere to the soil surface and improve temperature control. Furthermore, the covering mat 4 can adopt a composite structure of insulation blanket and straw layer, which not only has good heat insulation effect, but the straw layer is also a natural and environmentally friendly material. After natural degradation, it can increase soil organic matter and improve soil structure, achieving the dual effects of soil remediation and soil improvement without secondary pollution, which is in line with the concept of green and sustainable remediation.

[0041] The moving rod 33 of the equipment can be adapted to the structure of gear transmission and drive motor, and can be easily connected to temperature control units such as temperature sensing module and control module to realize the automatic linkage of real-time soil temperature monitoring and coverage adjustment of covering pad 4. No manual on-site supervision and adjustment is required, which provides a structural foundation for the intelligent upgrade of the equipment. In the future, it can further reduce manpower input and reduce the labor cost of restoration work.

[0042] Preferably, the inner ring guide rail 31 includes multiple inner arc tracks 310 connected in sequence, and the outer ring guide rail 32 includes multiple outer ring tracks 320 connected in sequence. The multiple outer ring tracks 320 correspond one-to-one with the multiple inner arc tracks 310 and are fixed by fixing rods 34. There are two sets of fixing rods 34, which are used to fix the two ends of the inner arc tracks 310 and the outer ring tracks 320 respectively. The two sets of fixing rods 34, the inner arc tracks 310, and the outer ring tracks 320 form a fan-shaped structure. At least one movable rod 33 is distributed on each fan-shaped structure. The two ends of the movable rod 33 are respectively slidably disposed in the inner arc tracks 310 and the outer ring tracks 320 through sliders 330.

[0043] The inner ring guide rail 31 is divided into multiple inner arc tracks 310, and the outer ring guide rail 32 is divided into multiple outer ring tracks 320. Each track is connected to a fixed rod 34 to form an independent fan-shaped structure. Each fan-shaped structure is individually equipped with a moving rod 33, allowing for independent adjustment of the unfolding / retraction of the covering pad 4 in different zones. To address temperature differences in different areas of the soil, the coverage rate of each fan-shaped structure corresponding to the insulation zone can be adjusted separately, avoiding overall temperature deviation and ensuring more precise temperature control in the microbial agent's action zone.

[0044] Each sector structure is an independent temperature control unit. When the inner arc track 310, outer ring track 320, moving rod 33 or slider 330 in a single sector structure malfunctions, it only affects the temperature control operation of that area. The remaining sector structures can operate normally without causing the overall temperature control of the equipment to fail. This greatly improves the stability and fault tolerance of the equipment operation and reduces the risk of interruption of on-site repair work.

[0045] The slider 330 of the moving rod 33 slides only within the inner arc track 310 and outer ring track 320 of the corresponding fan-shaped structure, which limits the sliding trajectory and avoids the offset and jamming problems when the moving rod 33 slides under the overall ring guide rail; at the same time, a single moving rod 33 corresponds to a single fan-shaped area, so the force is more even when adjusting, and the covering pad 4 is opened / closed more smoothly without wrinkles and accumulation, ensuring the uniformity of heat preservation / heat dissipation effect.

[0046] The inner arc track 310 and outer ring track 320 are modular guide rail components. Compared with the integral inner ring guide rail 31 and outer ring guide rail 32, they are easier to standardize and process, and are smaller and lighter, reducing transportation costs. During on-site installation, the modules can be assembled into a fan-shaped structure and then spliced ​​into an integral guide rail frame 3, which can adapt to the operating space of different construction sites and make the installation process simpler.

[0047] Each sector-shaped structure has independent components. During later equipment maintenance, the faulty inner arc track 310, outer ring track 320, or moving rod 33 can be accurately located. Only the faulty module needs to be disassembled and replaced, without the need to completely remove the guide rail frame 3. This greatly reduces maintenance time and operational difficulty, and lowers the later operation and maintenance costs of the equipment.

[0048] The number of inner arc track 310 and outer ring track 320 can be flexibly adjusted according to the size of the pre-embedded substrate 1 and the core area of ​​the soil to be repaired, thereby changing the number of fan-shaped structures and the area of ​​a single region, so that the size of the guide rail frame 3 can be precisely matched with the repair needs of the insulation area, and the scene adaptability of the equipment can be improved.

[0049] Preferred, such as Figure 1 , Figure 3As shown, the covering pad 4 includes multiple fan-shaped pads 40, which are distributed one-to-one on multiple fan-shaped structures, and the opposite ends of two adjacent fan-shaped pads 40 form an opening.

[0050] The sector-shaped pads 40 correspond one-to-one with the sector-shaped structures formed by the inner arc track 310, the outer ring track 320, and the fixed rod 34, allowing the temperature control adjustment of each sector area to form an independent closed loop. The sliding of the moving rod 33 only causes the sector-shaped pads 40 in the corresponding area to unfold or retract, without affecting the coverage status of other sector-shaped pads 40. This completely realizes precise temperature control of the soil insulation area by zone, solving the problem that the overall covering pad can be adjusted once and for all, and cannot adapt to local temperature differences in the soil.

[0051] The coverage area of ​​a single sector pad 40 is smaller and the force is more concentrated. When the moving rod 33 slides, it drives the sector pad 40 to unfold / fold. The pad is not prone to wrinkles, accumulation or stretching deformation. It can always fit tightly against the soil surface above the corresponding sector structure, avoiding heat loss / poor heat dissipation caused by the pad not fitting properly, and ensuring more stable heat preservation and heat dissipation effects in each zone.

[0052] Each sector pad 40 is independent of the others. If a sector pad 40 in a certain area is damaged due to soil friction, environmental erosion, etc., only that single sector pad 40 needs to be replaced, without replacing the entire cover pad 4, which greatly reduces the cost of replacing parts. At the same time, the replacement operation can be carried out separately in the corresponding sector area without removing other parts, making the operation simpler and not affecting the normal temperature control operation of other areas of the equipment.

[0053] The sector-shaped pad 40 is a modular flexible component, with a volume and weight much smaller than the integral ring-shaped covering pad 4. During on-site construction, it can be laid and fixed in stages along with the assembly of the sector-shaped guide rail structure, without the need for overall winding of a large-sized pad, which reduces the difficulty of laying and is especially suitable for contaminated soil sites with limited construction space. In addition, the fixing points of the sector-shaped pad 40 with the moving rod 33 and the fixed rod 34 are more concentrated, making the installation and positioning more precise.

[0054] The number of fan-shaped structures on the guide rail frame 3 can be flexibly adjusted according to the size of the core area of ​​the soil to be repaired. At the same time, the number of fan-shaped pads 40 can be increased or decreased. There is no need to re-customize the integral covering pad 4, so that the structural adjustment of the covering pad 4 and the guide rail frame 3 can always be adapted, which further improves the adaptability of the equipment to different repair ranges and different pre-embedded substrate 1 sizes.

[0055] During adjustment, the integral ring-shaped cover pad 4 is prone to overall tensile stress due to synchronous sliding of different areas, which can lead to seam cracking and accelerated aging of the pad over long-term use. In contrast, the sector-shaped pad 40 only performs localized expansion and contraction within its respective sector area, significantly reducing the tensile stress on the pad and effectively alleviating aging and damage problems, thus extending the overall service life of the cover pad 4.

[0056] Preferred, such as Figure 4 As shown, a movable rod 33 is distributed on the fan-shaped structure. One end of the fan-shaped pad 40 is fixed to any fixed rod 34, and the other end is fixed to the movable rod 33 inside the fan-shaped structure.

[0057] Each movable rod 33 corresponds to a single sector structure and sector pad 40. The sliding motion of the movable rod 33 along the inner arc track 310 and the outer ring track 320 can directly and precisely drive the sector pad 40 to unfold or retract without interference from extra transmission components. This enables stepless and precise adjustment of the coverage rate of a single sector area. Furthermore, the force transmission of the single rod drive is more direct, and the response speed of temperature control is faster, allowing for rapid adaptation to real-time changes in local soil temperature.

[0058] Each sector structure is equipped with only one moving rod 33, and the sector pad 40 only needs to be fixed at both ends to the fixed rod 34 and the moving rod 33 respectively, without the need for additional support or fixing components, which greatly simplifies the connection structure between the guide rail frame 3 and the cover pad 4. This not only reduces the production material cost of accessories such as the moving rod 33 and the slider 330, but also makes the positioning and fixing operations of on-site assembly simpler and shortens the construction cycle.

[0059] One end of the sector-shaped pad 40 is fixed to the stationary fixed rod 34, while the other end is driven by the moving rod 33 to slide in an arc. The stretching and shrinking of the pad is subject to a single force direction and extends along the arc of the sector structure. This avoids the force offset and localized pulling problems caused by multiple rods, effectively reducing the wrinkles and tearing of the sector-shaped pad 40. At the same time, the load of a single moving rod 33 is only the tension of a single sector-shaped pad 40, and the meshing force between the slider 330 and the track is more uniform, reducing the wear of the guide rail and the slider 330 and extending the service life of the transmission components.

[0060] Temperature control adjustment in a single sector area involves only a single moving rod 33 and a set of sliders 330, resulting in fewer components, more concentrated fault points, and easier troubleshooting. If adjustment becomes stuck or sliding fails in a certain area, the corresponding moving rod 33 or slider 330 can be directly located without disassembling multiple rods. Maintenance only requires inspection and replacement of a single moving rod 33, simplifying operation and not affecting the normal operation of other areas.

[0061] Preferably, both the inner arc track 310 and the outer ring track 320 are provided with teeth, and the slider 330 is rotatably provided with a gear that meshes with the teeth. The slider 330 is also provided with a drive motor connected to the gear for driving the gear to rotate.

[0062] The teeth of the inner arc track 310 and the outer ring track 320 precisely mesh with the gears on the slider 330, forming a rigid transmission structure that completely avoids slippage and offset problems that are prone to occur in conventional sliding fits. The sliding stroke of the moving rod 33 is in a fixed proportional relationship with the number of rotations of the drive motor, which enables precise control of the position of the moving rod 33, thereby precisely adjusting the coverage of the sector pad 40 to meet the precise temperature control requirements for subtle changes in soil temperature.

[0063] The meshing transmission of gears and teeth has a large contact area and low power loss, allowing the power of the drive motor to be efficiently transmitted to the slider 330, which in turn drives the moving rod 33 to slide smoothly along the track. Furthermore, the meshing transmission starts and stops without lag, enabling rapid response to the adjustment commands of the temperature control unit 5. When the soil temperature deviates from the suitable range, the moving rod 33 can be immediately driven to adjust the coverage of the fan-shaped pad 40, achieving rapid temperature correction.

[0064] The gear meshing structure has a mechanical self-locking characteristic. When there is no power input from the drive motor, the gear will not slide along the teeth, allowing the moving rod 33 to remain stably in the preset position, and the coverage of the sector pad 40 to remain fixed. Even when encountering external disturbances such as wind or slight soil settlement, the moving rod 33 will not shift or the pad coverage will change, ensuring the stability of the temperature control effect.

[0065] The drive motor and gear transmission structure can be directly electrically connected to the control module 52 of the temperature control unit 5. The control module 52 can accurately control the forward and reverse rotation and the number of rotations of the drive motor according to the soil temperature signal of the temperature sensing module 51, so as to realize the fully automatic linkage of sliding of the moving rod 33 and adjustment of the coverage of the fan-shaped pad 40. No manual on-site operation is required, which greatly improves the intelligence level of the equipment and reduces labor costs.

[0066] The sliders 330 at both ends of the moving rod 33 engage synchronously with the teeth of the inner arc track 310 and the outer ring track 320, respectively, ensuring that the moving rod 33 slides smoothly along the arc trajectory and avoiding problems such as unilateral deviation and track jamming. This makes the adjustment of the fan-shaped pad 40 by the moving rod 33 smoother, further ensuring the flatness of the pad and the soil adhesion.

[0067] Preferred, such as Figure 3 As shown, the remediation equipment also includes a temperature control unit 5, which includes a temperature sensing module 51 and a control module 52. The temperature sensing module 51 is installed at the bottom of the pre-buried substrate 1 to collect the temperature signal of the soil near the bottom of the pre-buried substrate 1; the control module 52 is electrically connected to the temperature sensing module 51 and the drive motor respectively, and is used to receive the temperature signal and control the operation of the drive motor.

[0068] The temperature sensing module 51 is installed at the bottom of the pre-embedded substrate 1. This location is the core repair area where the microbial agent diffuses through the temporary storage chamber 10 and the drainage branch pipe 2. It can directly and accurately collect the real soil temperature of the functional microorganisms' growth and metabolism, avoid the interference of surface temperature measurement errors, and ensure that the temperature data can truly reflect the growth environment of the microorganisms, providing a precise basis for temperature control.

[0069] The control module 52 is electrically linked with the temperature sensing module 51 and the drive motor to form an unmanned temperature control closed loop: the temperature sensing module 51 transmits temperature signals to the control module 52 in real time, and the control module 52 automatically compares the preset suitable temperature threshold for microorganisms. Without manual judgment and operation, it directly sends forward and reverse rotation and start and stop commands to the drive motor, which drives the moving rod 33 to adjust the coverage of the fan-shaped pad 40, thereby realizing automatic temperature correction and greatly reducing on-site manpower input.

[0070] The real-time acquisition of temperature sensing module 51 and the instant judgment of control module 52 can immediately trigger the drive motor to act when the soil temperature deviates from the suitable range of 25℃~30℃, quickly adjust the heat preservation / heat dissipation state of the covering pad 4, avoid the continuous temperature deviation leading to the inhibition of microbial activity and the decrease in remediation efficiency, and ensure that the temperature of the core remediation area is always stable in the optimal range.

[0071] The temperature control unit 5 is deeply adapted to the toothed gear transmission structure of the inner arc track 310 and the outer ring track 320. The instructions sent by the control module 52 can be accurately transmitted to the slider 330 and the moving rod 33 through the drive motor, so that the temperature signal corresponds precisely with the mechanical adjustment action. This not only ensures the accuracy of temperature control adjustment, but also makes the mechanical structure of the equipment and the electrical control system form an organic whole, improving the overall intelligent coordination of the equipment.

[0072] Preferred, such as Figure 4 As shown, the covering mat 4 includes an insulation blanket 41 and a straw layer 42 covering the insulation blanket 41. The straw layer 42 is a straw mat, which includes straw bundles and woven rope nets for binding the straw bundles. The length direction of the straw bundles is consistent with the length direction of the moving rod 33. In this embodiment, the straw layer 42 uses a rice straw mat with a thickness of 0.5cm to 1cm.

[0073] The insulation blanket 41 serves as the core insulation layer, directly blocking heat exchange between the soil and the outside world, achieving a basic constant temperature insulation effect. The straw layer 42 surrounding it has a natural porous structure, allowing air to fill the gaps in the straw bundles, forming an air insulation layer. Together with the insulation blanket 41, it forms a double-layer temperature control structure, significantly improving the insulation and heat insulation capabilities of the warm area, and more efficiently stabilizing the soil temperature within the suitable range for microorganisms.

[0074] The straw layer 42 uses natural straw bundles as raw materials, without any chemical additives. It will naturally degrade during the soil remediation process. After degradation, it can increase the soil organic matter content, improve the soil aggregate structure, and enhance soil fertility. This allows the cover pad 4 to not only have temperature control functions, but also to simultaneously achieve soil remediation and soil improvement. Unlike traditional rigid / non-degradable insulation materials, it fully complies with the concept of green and environmentally friendly soil remediation and has no secondary pollution.

[0075] The straw layer 42 binds the straw bundles with woven rope netting, which can fix the loose straw bundles into a whole structure and prevent the straw from scattering due to factors such as wind, rain, and sliding of the moving rod 33. This ensures that the straw layer 42 always completely covers the insulation blanket 41 and continues to perform its heat insulation effect. At the same time, the woven rope netting is also made of flexible material, which does not restrict the overall expansion and contraction adjustment of the covering pad 4 and is compatible with the expansion / contraction action driven by the moving rod 33.

[0076] The length direction of the straw bundle is consistent with the length direction of the moving rod 33. When the moving rod 33 drives the fan-shaped pad 40 to unfold or retract, the straw bundle will be subjected to force in the direction of the extension and contraction of the pad. There will be no bending or breakage of the straw bundle due to lateral force, nor will the straw layer 42 be wrinkled or torn. This ensures the structural integrity of the composite covering pad 4 and extends the overall service life.

[0077] The insulation blanket 41 is a conventional temperature control consumable, the straw bundle is agricultural waste, the raw materials are readily available and inexpensive, and the woven rope net is also a common textile material. Compared with high-end insulation pads made entirely of chemical materials, the overall production cost of this composite covering pad 4 is significantly reduced. At the same time, the modular fan-shaped pad 40 design allows for mass production and replacement as needed, fully adapting to the engineering application needs of large-area heavy metal contaminated soil remediation and controlling the overall remediation cost.

[0078] The porous structure of the straw bundle not only provides insulation but also has good air permeability. When the soil temperature is too high and heat dissipation is needed, the fan-shaped pad 40 is partially closed, allowing outside air to enter the soil surface through the gaps in the straw layer 42, thus accelerating heat dissipation. Compared to completely sealed insulation materials, this structure can meet both insulation and heat dissipation needs, making temperature control more flexible and adaptable to temperature changes in different seasons.

[0079] A method for remediating heavy metal contaminated soil, utilizing remediation equipment, includes the following steps: Excavate a foundation pit that is consistent with the bottom of the pre-embedded base 1, and dig drip troughs around the foundation pit that correspond to the number and position of the drainage branch pipes 2.

[0080] Place the pre-embedded base 1 in the foundation pit and place the drainage branch pipes 2 one by one in the dripping tank; backfill the soil so that the bottom of the pre-embedded base 1 and the drainage branch pipes 2 are buried in the soil.

[0081] The microbial agent preparation unit is connected to the temporary storage chamber 10 and the microbial agent is injected into the temporary storage chamber 10; the sliding rod 33 adjusts the covering pad 4 to cover the warm area.

[0082] Example 2 Unlike Embodiment 1, in the preferred embodiment, multiple movable rods 33 are distributed on the fan-shaped structure, the two ends of the fan-shaped pad 40 are respectively fixed on two movable rods 33 located at the edge of the fan-shaped structure, and the middle section of the fan-shaped pad 40 is uniformly fixed on other movable rods 33.

[0083] The fan-shaped pad 40 is fixed at both ends to the movable rods 33 along the edge of the fan-shaped structure, and the middle section is evenly fixed to the remaining movable rods 33. Multiple rods form uniform support and fixing points, ensuring the fan-shaped pad 40 remains flat throughout its unfolding and retraction process, preventing localized sagging, wrinkling, or bulging. It adheres tightly to the soil surface, completely avoiding heat loss due to gaps between the pad and the soil, resulting in a more uniform and stable insulation / heat dissipation effect in the fan-shaped area.

[0084] Multiple movable rods 33 slide synchronously to adjust the fan-shaped pad 40, evenly distributing the tensile and contractile stress of the pad to multiple fixed points. This avoids the problem of stress concentration at one end of the pad when controlled by a single rod. It can effectively reduce cracking and aging of the fan-shaped pad 40 due to localized stretching, and significantly extend the service life of the fan-shaped pad 40, making it especially suitable for long-term outdoor use of flexible pads.

[0085] Multiple movable rods 33 within the fan-shaped structure slide synchronously along the inner arc track 310 and the outer ring track 320, forming a coordinated power transmission that drives the fan-shaped mat 40 to smoothly extend and retract in an arc shape. This avoids the jamming and displacement problems caused by uneven force on the mat body when driven by a single rod. At the same time, the synchronous sliding of multiple rods makes the expansion / contraction speed of the mat body more uniform, enabling precise control of the coverage rate and adapting to subtle changes in soil temperature.

[0086] For large-sized fan-shaped structures that accommodate larger remediation areas, the support and driving capacity of a single moving rod 33 is insufficient, easily leading to pad deformation and adjustment failure. However, the multi-point fixing and synchronous driving of multiple moving rods 33 effectively adapts to the adjustment needs of large-sized fan-shaped pads 40, allowing for flexible adjustment of the fan-shaped structure's size according to the remediation area, further expanding the equipment's adaptability to different contaminated soil areas.

[0087] Multiple movable poles (33) provide multi-point support to the fan-shaped mat (40), making the overall structure of the mat more stable. This effectively resists interference from external factors such as wind, rain erosion, and slight soil surface settlement, preventing the mat from shifting or tilting. Even in complex outdoor soil environments, it maintains a stable coverage state, ensuring continuous temperature control.

[0088] Example 3 Unlike Example 2, the preferred embodiment is as follows: Figure 6 As shown, there are multiple sets of in-situ injection units, and each set of in-situ injection units corresponds to a set of microbial agent preparation units. The temporary storage chamber 10 of each set of in-situ injection units is connected to the microbial agent preparation unit.

[0089] The in-situ injection unit is an independent modular structure. Multiple in-situ injection units can be matched with the same microbial agent preparation unit, allowing for flexible deployment based on the area of ​​contaminated soil. This enables simultaneous agent addition and temperature control for large-area heavy metal contaminated soil, significantly improving remediation efficiency and adapting to large-scale soil remediation needs. Only one core microbial agent preparation unit needs to be deployed, paired with multiple structurally uniform in-situ injection units. The overall equipment layout is simpler, eliminating the need to disperse multiple microbial preparation devices across the remediation site, greatly reducing the amount of piping and wiring work. Furthermore, during operation, only one core microbial preparation area needs to be managed to supply agents to all injection units, significantly reducing the difficulty of on-site construction and subsequent operation management.

[0090] The microbial inoculants are centrally prepared and mixed in a single preparation unit, ensuring that the inoculants delivered to the temporary storage chambers 10 of each in-situ injection unit are completely consistent in key indicators such as concentration, viable cell count, and activity. This avoids the quality differences caused by dispersed inoculant preparation in multiple preparation units, ensuring uniform and consistent microbial remediation effects throughout the entire remediation area and eliminating problems such as inconsistent remediation results and substandard local remediation due to differences in inoculant quality. The single preparation unit can uniformly control and precisely measure the inoculant delivery volume of each in-situ injection unit. It can synchronously adjust the inoculant injection rate and total amount in all temporary storage chambers 10 according to the degree of soil pollution in the remediation area, achieving precise quantitative inoculant dosing throughout the entire remediation area. It can also uniformly start and stop the inoculant supply according to the progress of soil remediation, making the management and control of remediation operations more efficient and precise.

[0091] Each in-situ injection unit is an independent modular structure, which can be flexibly deployed according to the actual shape and terrain characteristics of the contaminated soil, such as corners, gullies, and irregular boundaries. It is only necessary to connect the temporary storage chamber 10 of each pre-embedded substrate 1 to the central preparation unit through pipelines. There is no need to change the structure of the preparation unit. The equipment has stronger adaptability to complex sites and can achieve full coverage remediation of contaminated soil without dead ends. If it is necessary to expand the remediation area during the remediation process, or if the local soil contamination level is found to be higher and additional injection points need to be added, it is only necessary to add an in-situ injection unit in the corresponding area and connect its temporary storage chamber 10 to the original preparation unit. There is no need to add new bacteria preparation equipment. The subsequent expansion of the equipment is more convenient and less costly. It is also possible to flexibly shut down some injection units in the qualified areas according to the remediation progress, so as to realize the dynamic adjustment of the remediation operation.

[0092] The specific models of the above electronic components are not specifically specified; any commercially available ordinary products can be selected, as long as they can meet the usage requirements of this invention.

[0093] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above descriptions are merely specific embodiments of the present invention and do not limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention are included within the protection scope of the present invention.

Claims

1. A heavy metal contaminated soil remediation device, comprising a microbial agent preparation unit and an in-situ injection unit, wherein the microbial agent preparation unit is connected to the in-situ injection unit and is injected into the heavy metal contaminated soil to be remediated through the in-situ injection unit; characterized in that, The in-situ injection unit includes: The pre-embedded substrate is buried at the bottom in the heavy metal contaminated soil to be remediated. The interior of the pre-embedded substrate has a temporary storage cavity, which is connected to the microbial agent preparation unit. There are multiple drainage branches, which are arranged around the pre-embedded substrate. All drainage branches are buried in the heavy metal contaminated soil to be remediated. The inlet end of the drainage branch is connected to the temporary storage chamber, and the other end of the drainage branch is closed. Multiple liquid outlets are opened on its side wall. The liquid outlets are used as outlets to discharge microbial agents. The guide rail frame includes: an inner ring guide rail, fixed on the outer wall of the pre-embedded substrate; an outer ring guide rail, coaxially arranged with the inner ring guide rail, forming a heat preservation area between the outer ring guide rail and the inner ring guide rail; and multiple movable rods, which are evenly distributed in the heat preservation area. Each movable rod has a slider at both ends and is slidably mounted on the inner ring guide rail and the outer ring guide rail through the sliders. The covering pad is made of flexible pad body. The covering pad has a circular structure and at least one opening in the radial direction. The ends of the covering pad located on both sides of the opening are fixed to two adjacent moving rods. The bottom surface of the covering pad is fixed to other moving rods. By sliding the moving rods, the ends of the covering pad can be moved to adjust the size of the opening, thereby adjusting the coverage of the covering pad above the heat preservation area.

2. The heavy metal contaminated soil remediation equipment as described in claim 1, characterized in that, The inner ring guide rail includes multiple inner arc tracks connected in sequence, and the outer ring guide rail includes multiple outer ring tracks connected in sequence. The multiple outer ring tracks correspond one-to-one with the multiple inner arc tracks and are fixed by fixing rods. There are two sets of fixed rods, which are used to fix the two ends of the inner arc track and the outer ring track respectively. The two sets of fixed rods, the inner arc track and the outer ring track form a fan-shaped structure. At least one movable rod is distributed on each fan-shaped structure. The two ends of the movable rod are slidably set in the inner arc track and the outer ring track respectively through the slider.

3. The heavy metal contaminated soil remediation equipment as described in claim 2, characterized in that, The covering pad includes multiple fan-shaped pads, which are distributed one-to-one on multiple fan-shaped structures, and the opposite ends of two adjacent fan-shaped pads form the opening.

4. The heavy metal contaminated soil remediation equipment as described in claim 3, characterized in that, One of the movable rods is distributed on the fan-shaped structure. One end of the fan-shaped pad is fixed to any fixed rod, and the other end is fixed to the movable rod inside the fan-shaped structure.

5. The heavy metal contaminated soil remediation equipment as described in claim 3, characterized in that, The fan-shaped structure has multiple movable rods distributed on it. The two ends of the fan-shaped pad are fixed to two movable rods located at the edge of the fan-shaped structure, and the middle section of the fan-shaped pad is evenly fixed to other movable rods.

6. A heavy metal contaminated soil remediation and treatment equipment as described in any one of claims 2-5, characterized in that, Both the inner arc track and the outer ring track are equipped with teeth, and the slider is rotatably equipped with gears that mesh with the teeth. Each slider is also equipped with a drive motor connected to the gears for driving the gears to rotate.

7. The heavy metal contaminated soil remediation equipment as described in claim 6, characterized in that, It also includes a temperature control unit, which includes: The temperature sensing module is installed at the bottom of the pre-embedded substrate to collect the temperature signal of the soil near the bottom of the pre-embedded substrate. The control module is electrically connected to the temperature sensing module and the drive motor, respectively, and is used to receive temperature signals and control the operation of the drive motor.

8. The heavy metal contaminated soil remediation equipment as described in claim 1, characterized in that, There are multiple sets of in-situ injection units, and each set of in-situ injection units corresponds to a set of microbial agent preparation units. The temporary storage chamber of each set of in-situ injection units is connected to the microbial agent preparation unit.

9. The heavy metal contaminated soil remediation equipment as described in claim 1, characterized in that, The covering pad includes an insulation blanket and a straw layer covering the insulation blanket. The straw layer includes straw bundles and a woven rope net for binding the straw bundles. The length direction of the straw bundles is consistent with the length direction of the moving rod.

10. A method for remediating heavy metal contaminated soil, characterized in that, The remediation and treatment of heavy metal contaminated soil using the remediation and treatment equipment described in claim 1 includes the following steps: Excavate a foundation pit that is consistent with the bottom of the pre-embedded substrate, and excavate drip grooves around the foundation pit that correspond to the number and position of the drainage branch pipes; Place the pre-embedded substrate in the foundation pit and place the drainage branch pipes one by one in the drip trough; backfill the soil so that the bottom of the pre-embedded substrate and the drainage branch pipes are buried in the soil. The microbial agent preparation unit is connected to the temporary storage chamber, and the microbial agent is injected into the temporary storage chamber; the sliding rod adjusts the covering pad to cover the warm area.

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