A biomass carbon landfill layer structure for adsorbing Cd and a Cd adsorption monitoring method

Abstract

A biochar landfill structure for adsorbing Cd and a Cd adsorption monitoring method relate to the field of soil remediation and Cd adsorption. It includes a sampling column, a first base layer, a second base layer, an adsorption layer, a first covering layer and a second covering layer. The adsorption layer is composed of biochar. The sampling column penetrates the adsorption layer. The sampling column includes an outer tube, a rotating shaft, a turntable and a sampling tube. The rotating shaft is rotatably arranged in the tube cavity of the outer tube, and the turntable is connected to the rotating shaft. The tail end of the sampling tube is hinged to the turntable. The tube wall of the outer tube is provided with a sampling port, and the sampling end of the sampling tube can be slidably matched with the sampling port. The rotating shaft is used to drive the turntable to rotate so that the sampling tube can extend from the sampling port and retract as the turntable rotates further, thereby completing the sampling. It has a simple structure, is easy to implement, and has low implementation difficulty. It can effectively and continuously improve the soil and adsorb Cd in the soil.

Description

Technical Field

[0001] The present invention relates to the field of soil remediation and Cd adsorption, and in particular to a biomass charcoal landfill layer structure for adsorbing Cd and a Cd adsorption monitoring method. Background Art

[0002] Cd contamination of soil and food crops is a widespread environmental problem caused by uncontrolled industrialization, unsustainable urbanization and intensive agricultural practices. As a class of toxic substances, Cd poses a high threat to soil quality, food safety and human health. The control of soil Cd pollution is urgent.

[0003] In view of this, this application is hereby filed. Summary of the invention

[0004] The first purpose of the present invention is to provide a biomass charcoal landfill layer structure for adsorbing Cd, which has a simple structure, is easy to implement, and has low implementation difficulty. It can effectively and continuously improve the soil, adsorb Cd in the soil, and effectively remove Cd in the soil, which helps to continuously improve soil quality and improve crop quality. In addition, it is easy to monitor and control, and can very conveniently evaluate the adsorption situation, which is convenient for subsequent maintenance and continuous optimization, and has positive significance for continuously improving the adsorption effect.

[0005] The second object of the present invention is to provide a Cd adsorption monitoring method, which is simple to operate and easy to implement, and can very conveniently sample the adsorption layer, which has positive significance for continuous monitoring and optimization of the adsorption effect.

[0006] The embodiment of the present invention is achieved as follows:

[0007] A biomass charcoal landfill structure for adsorbing Cd comprises: a sampling column, and a first base layer, a second base layer, an adsorption layer, a first covering layer and a second covering layer arranged in sequence from bottom to top. The first base layer and the first covering layer are both composed of gravel, the second base layer is composed of mud and sand, the second covering layer is a soil layer, and the adsorption layer is composed of biomass charcoal. The sampling column penetrates to the adsorption layer.

[0008] The sampling column includes an outer tube and an inner core, wherein the inner core includes a rotating shaft, a rotating disk and a sampling tube. The rotating shaft is rotatably arranged in the tube cavity of the outer tube and arranged along the length direction thereof, and the rotating disk is fixedly connected to the rotating shaft. The tail end of the sampling tube is hinged to the disk surface of the rotating disk.

[0009] The outer tube wall is provided with a sampling port for the sampling tube to extend out, and the sampling end of the sampling tube can be slidably matched with the sampling port. The rotating shaft is used to drive the rotating disk to rotate so that the sampling tube can extend out of the sampling port and retract as the rotating disk further rotates, thereby completing the sampling.

[0010] Furthermore, the sampling port is provided with a guide sleeve, which is universally rotatable at the sampling port, and the sampling tube is slidably matched with the guide sleeve.

[0011] Furthermore, the guide sleeve is spherical and can be universally rotatably embedded in the sampling port. The guide through hole of the guide sleeve is arranged along its radial direction, and a rubber ring is accommodated at the outer end of the guide through hole. The rubber ring is arranged in a manner that fits the hole wall of the guide through hole and extends in a ring shape along the circumference of the guide through hole. The sampling tube is interference fit with the rubber ring and can slide.

[0012] Furthermore, the guide sleeve also has an extended guide section, which is connected to its outer wall and arranged along its radial direction, and has a guide slide groove for accommodating the sampling tube, which is connected to the guide through hole. Along the axial direction of the guide through hole, the sampling tube can slidably cooperate with the guide slide groove.

[0013] Furthermore, the cross section of the extended guide section is in a fan-shaped ring shape, and the groove wall of the guide groove and the hole wall of the guide through hole are located on the same cylindrical surface.

[0014] Furthermore, a stopper is provided at the end of the sampling end of the sampling tube, one end of the stopper is connected to the end wall of the sampling tube, and the other end extends toward the tail end of the sampling tube and toward the central axis of the sampling tube. The stopper is continuously provided in a ring shape along the circumference of the sampling tube.

[0015] Furthermore, the inner core also includes a sliding frame. Along the axial direction of the outer tube, the sliding frame is slidably matched with the inner wall of the outer tube. Along the circumferential direction of the outer tube, the sliding frame is fixedly matched with the inner wall of the outer tube. The rotating shaft is slidably matched with the sliding frame. The turntable has a first rotation stop point, a second rotation stop point and a third rotation stop point. When the turntable is located at the first rotation stop point, the sampling end of the sampling tube is accommodated in the extended guide section. When the turntable is located at the second rotation stop point, the length of the sampling tube extending through the guide sleeve reaches a maximum value. When the turntable is located at the third rotation stop point, the sampling end of the sampling tube retracts to the extended guide section.

[0016] Furthermore, the inner core has multiple groups of turntables, which are arranged at intervals along the axial direction of the rotating shaft. Each turntable is equipped with a sampling tube, and each sampling tube is provided with a corresponding sampling port. Along the circumference of the outer tube, the sampling ports corresponding to the sampling tubes of all turntables are staggered.

[0017] Furthermore, the inner core also has a reinforcement plate, which is fixedly connected to the sliding frame, and the rotating shaft passes through the reinforcement plate and is rotatably matched with the reinforcement plate.

[0018] A Cd adsorption monitoring method using the above-mentioned biomass carbon landfill structure for adsorbing Cd comprises: driving the rotating shaft to rotate in a directional manner to complete sampling, and extracting the sampling column to take out the sample.

[0019] The beneficial effects of the embodiments of the present invention are:

[0020] The overall structure of the biomass charcoal landfill structure for adsorbing Cd provided by the embodiment of the present invention has a first base layer composed of crushed stone at the bottom, which can play a main supporting role and reduce local collapse and layered structure deformation. The second base layer composed of mud and sand can play an auxiliary supporting role, and the first covering layer composed of mud and sand can "cap" the adsorption layer to avoid tearing of the adsorption layer, enhance the flatness and density of the adsorption layer, and the second base layer and the first covering layer also improve the compatibility of the adsorption layer with the surrounding environment, which is convenient for the smooth adsorption of Cd ions. The second covering layer is a soil layer, which is used to deeply bury the main functional part of the biomass charcoal landfill structure.

[0021] During use, when it is necessary to sample the adsorption layer, the rotating shaft is rotated. During the rotation of the turntable, the tail end of the sampling tube rotates eccentrically with the turntable. Under the guidance of the sampling port, the sampling tube will slide along the sampling port, so that the sampling tube is inserted from the sampling port into the adsorption layer, and the biochar in the adsorption layer is collected into the sampling tube to complete the sampling.

[0022] Through the above operation, the sampling of the adsorption layer can be completed conveniently. After the sampling is completed, the sampling column is extracted, and the sample in the sampling tube is taken out. By detecting the total Cd element adsorbed in the sample, the adsorption capacity of the adsorption layer and the overall effect of the biochar landfill structure can be directly evaluated. Through the detection of the sample, the residual adsorbable amount, adsorption efficiency, and adsorption stability of the biochar landfill structure can also be comprehensively evaluated, which is of positive significance for continuously optimizing the overall performance of the biochar landfill structure and mastering the soil improvement situation.

[0023] For example, if it is detected that the biochar in the adsorption layer has been saturated with the Cd element, the adsorption layer can be dug out for unified recycling, and a new adsorption layer can be redeployed for the next cycle of Cd adsorption.

[0024] In general, the biomass charcoal landfill layer structure for adsorbing Cd provided by the embodiment of the present invention is simple in structure, easy to implement, and has low implementation difficulty. It can effectively and continuously improve the soil, adsorb Cd in the soil, and effectively remove Cd in the soil, which helps to continuously improve the soil quality and improve the quality of crops; in addition, it is easy to monitor and control, and can very conveniently evaluate the adsorption situation, which is convenient for subsequent maintenance and continuous optimization, and has positive significance for continuously improving the adsorption effect. The Cd adsorption monitoring method provided by the embodiment of the present invention is simple to operate and easy to implement, and can very conveniently sample the adsorption layer, which has positive significance for continuously monitoring and optimizing the adsorption effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments are briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without creative work.

[0026] Figure 1 A schematic diagram of the structure of a biomass charcoal landfill layer provided in an embodiment of the present invention;

[0027] Figure 2 for Figure 1 A schematic diagram of the structure of the sampling column of the biomass charcoal landfill structure when the turntable is at the first rotation stop point;

[0028] Figure 3 for Figure 1 A schematic diagram of the structure of the sampling column of the medium biomass charcoal landfill structure when the turntable is in the middle state;

[0029] Figure 4 for Figure 1 A schematic diagram of the structure of the sampling column of the biomass charcoal landfill structure when the turntable is at the third rotation stop point;

[0030] Figure 5 for Figure 2 A schematic diagram of the structure of the guide sleeve of the middle sampling column;

[0031] Figure 6 for Figure 2 A schematic diagram of the structure of the sampling tube of the middle sampling column;

[0032] Figure 7 for Figure 2 Schematic diagram of the matching relationship of the reinforcement plate of the middle sampling column;

[0033] Figure 8 It is a schematic diagram of the structure of the second group of turntables arranged in sequence;

[0034] Fig. 9 It is a schematic diagram of the structure of the third group of turntables arranged in sequence;

[0035] Fig.10 It is a schematic diagram of the structure of the fourth group of turntables arranged in sequence.

[0036] Icon: biochar landfill layer structure 1000; sampling column 100; outer tube 110; guide sleeve 120; guide through hole 121; rubber ring 122; extended guide section 123; guide groove 123a; rotating shaft 130; turntable 140; sampling tube 150; stopper 151; sliding frame 160; reinforcement plate 170; clearance gap 171; first base layer 200; second base layer 300; adsorption layer 400; first covering layer 500; second covering layer 600. DETAILED DESCRIPTION

[0037] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0038] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0039] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0040] The terms “first”, “second”, etc. are only used for distinguishing descriptions and should not be understood as indicating or implying relative importance.

[0041] In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0042] Example

[0043] Please refer to Figure 1This embodiment provides a biomass carbon landfill structure 1000 for adsorbing Cd. The biomass carbon landfill structure 1000 includes: a sampling column 100, and a first base layer 200, a second base layer 300, an adsorption layer 400, a first covering layer 500 and a second covering layer 600 arranged in sequence from bottom to top.

[0044] The first base layer 200 and the first cover layer 500 are both made of gravel, the second base layer 300 is made of mud and sand, the second cover layer 600 is a soil layer, and the adsorption layer 400 is made of biochar. The sampling column 100 penetrates the adsorption layer 400 .

[0045] It should be noted that the biomass charcoal may be tobacco stem biomass charcoal, tobacco stalk biomass charcoal, pine cone biomass charcoal, rape stem biomass charcoal, reed biomass charcoal, etc., but is not limited thereto. In this embodiment, the biomass charcoal of the adsorption layer 400 is reed biomass charcoal.

[0046] Regarding the overall structure of the biochar landfill structure 1000, the bottom is the first base layer 200 composed of crushed stone, which can play a main supporting role and reduce local collapse and layered structure deformation. The second base layer 300 composed of mud and sand can play an auxiliary supporting role, and the first cover layer 500 composed of mud and sand can "cap" the adsorption layer 400 to prevent the adsorption layer 400 from tearing and enhance the flatness and density of the adsorption layer 400. The second base layer 300 and the first cover layer 500 also improve the compatibility of the adsorption layer 400 with the surrounding environment, which is convenient for the smooth adsorption of Cd ions. The second cover layer 600 is a soil layer, which is used to bury the main functional part of the biochar landfill structure 1000.

[0047] It should be noted that the biochar landfill structure 1000 is more suitable for arable land and shallow Cd adsorption, and the thickness of the second cover layer 600 can generally be set at 50-100 cm, the thickness of the first cover layer 500 can generally be set at 10-20 cm, the thickness of the adsorption layer 400 can generally be set at 100-150 cm, the thickness of the second base layer 300 can generally be set at 10-20 cm, and the thickness of the first base layer 200 can generally be set at 25-35 cm. This makes it easier to replace the adsorption layer 400.

[0048] Please combine Figure 2 The sampling column 100 includes an outer tube 110 and an inner core, and the inner core includes a rotating shaft 130, a rotating disk 140 and a sampling tube 150. The rotating shaft 130 is rotatably arranged in the tube cavity of the outer tube 110 and arranged along the length direction thereof, and the rotating disk 140 is fixedly connected to the rotating shaft 130. The tail end of the sampling tube 150 is hinged to the disk surface of the rotating disk 140.

[0049] The outer tube 110 has a sampling port for the sampling tube 150 to extend out of the tube wall, and the sampling end of the sampling tube 150 can be slidably matched with the sampling port. The rotating shaft 130 is used to drive the rotating disk 140 to rotate, so that the sampling tube 150 can extend out of the sampling port and retract as the rotating disk 140 further rotates, thereby completing the sampling.

[0050] During use, when it is necessary to sample the adsorption layer 400, the rotating shaft 130 is rotated. During the rotation of the turntable 140, the tail end of the sampling tube 150 rotates eccentrically with the turntable 140. Under the guidance of the sampling port, the sampling tube 150 slides along the sampling port, so that the sampling tube 150 is inserted into the adsorption layer 400 from the sampling port, and the biomass charcoal in the adsorption layer 400 is collected into the sampling tube 150, and the sampling is completed. Figures 3-4 shown.

[0051] Through the above operation, the sampling of the adsorption layer 400 can be easily completed. After the sampling is completed, the sampling column 100 is extracted, and the sample in the sampling tube 150 is taken out. By detecting the total Cd element adsorbed in the sample, the adsorption capacity of the adsorption layer 400 and the overall effect of the biochar landfill structure 1000 can be directly evaluated. By detecting the sample, the residual adsorbable amount, adsorption efficiency, and adsorption stability of the biochar landfill structure 1000 can also be comprehensively evaluated, which is of positive significance for continuously optimizing the overall performance of the biochar landfill structure 1000 and mastering the soil improvement situation.

[0052] For example, if it is detected that the biochar in the adsorption layer 400 has been saturated with the Cd element, the adsorption layer 400 can be dug out for unified recycling, and a new adsorption layer 400 can be redeployed to perform the next cycle of Cd adsorption.

[0053] In general, the biochar landfill layer structure 1000 for adsorbing Cd has a simple structure, is easy to implement, and has low implementation difficulty. It can effectively and continuously improve the soil, adsorb Cd in the soil, and effectively remove Cd in the soil, which helps to continuously improve soil quality and improve crop quality. In addition, it is easy to monitor and control, and can very conveniently evaluate the adsorption situation, which is convenient for subsequent maintenance and continuous optimization, and has positive significance for continuously improving the adsorption effect.

[0054] In this embodiment, the central axis of the rotating shaft 130 and the central axis of the outer tube 110 are arranged to coincide with each other, the rotating disk 140 is arranged perpendicular to the rotating shaft 130, and the rotating shaft 130 and the rotating disk 140 are arranged coaxially. The central axis of the sampling tube 150 is arranged perpendicular to the central axis of the rotating shaft 130, and the tail end of the sampling tube 150 is eccentrically hinged to the disk surface of the rotating disk 140.

[0055] Furthermore, please combine Figure 5 The sampling port is provided with a guide sleeve 120 , which can be universally rotatably arranged at the sampling port, and the sampling tube 150 can be slidably matched with the guide sleeve 120 .

[0056] Specifically, the guide sleeve 120 is spherical and can be universally rotatably embedded in the sampling port. The guide through hole 121 of the guide sleeve 120 is arranged along its radial direction. The outer end of the guide through hole 121 accommodates a rubber ring 122, which is arranged to fit the hole wall of the guide through hole 121 and extends in a ring shape along the circumference of the guide through hole 121. The sampling tube 150 is interference fit with the rubber ring 122 and can slide. In this embodiment, a plurality of rubber rings 122 are arranged at intervals along the axial direction of the guide through hole 121.

[0057] Through the above design, the guide sleeve 120 and the outer tube 110 are more closely matched, which is not only convenient for guiding the movement of the sampling tube 150, but also more flexible, and can effectively prevent external soil or biochar particles from entering the tube cavity of the outer tube 110. In addition, the rubber ring 122 can improve the stability of the sampling tube 150 during movement, and on the other hand, it can also prevent external soil or biochar particles from entering the tube cavity of the outer tube 110, and at the same time has a cleaning effect on the sampling tube 150.

[0058] Furthermore, the guide sleeve 120 also has an extended guide section 123, which is located in the lumen of the outer tube 110, connected to the outer wall thereof and arranged along its radial direction, and has a guide groove 123a for accommodating the sampling tube 150, and the guide groove 123a is connected to the guide through hole 121. Along the axial direction of the guide through hole 121, the sampling tube 150 is slidably matched with the guide groove 123a.

[0059] Specifically, the cross section of the extended guide section 123 is in the shape of a fan ring, and the groove wall of the guide groove 123a and the hole wall of the guide through hole 121 are located on the same cylindrical surface. The sampling tube 150 is detachably eccentrically hinged to the disk surface of the rotating disk 140.

[0060] Through the above design, the extended guide section 123 is used as a pre-guide for introducing the sampling tube 150 into the guide sleeve 120, which not only improves the matching accuracy of the sampling tube 150 and the guide sleeve 120, but also provides a larger travel space for the movement of the sampling tube 150, and at the same time facilitates the sampling tube 150 to be completely withdrawn from the guide sleeve 120 to the extended guide section 123, so that the sampling tube 150 can be completely retracted into the tube cavity of the outer tube 110, which is convenient for removing the core body from the outer tube 110, so that the sampling tube 150 can be more conveniently removed for sampling.

[0061] Furthermore, please combine Figure 6The end of the sampling end of the sampling tube 150 is provided with a stopper 151, one end of the stopper 151 is connected to the end wall of the sampling tube 150, and the other end extends toward the tail end of the sampling tube 150 and extends toward the central axis of the sampling tube 150. The stopper 151 is continuously arranged in a ring shape along the circumference of the sampling tube 150. Through this design, it is possible to effectively prevent the biomass charcoal sample that has entered the sampling tube 150 from escaping from the sampling tube 150. At the same time, in the process of collecting the sample, the stopper 151 can compress the sample to a certain extent, causing the sample to be compressed into a columnar shape with an outer diameter smaller than the inner diameter of the sampling tube 150. In this way, it is possible to prevent the sample from being blocked in the sampling tube 150 when taking out the sample, making it easier to take out the sample.

[0062] In order to make it easier to take out the sample, the sampling tube 150 is provided with two ends that can be detachably connected. When sampling, the sampling tube 150 is disassembled into two sections, and the sample can be poured out smoothly.

[0063] Please combine Figures 7-10 In this embodiment, the inner core further includes a sliding frame 160. The sliding frame 160 is slidably matched with the inner wall of the outer tube 110 along the axial direction of the outer tube 110. The sliding frame 160 is fixedly matched with the inner wall of the outer tube 110 along the circumferential direction of the outer tube 110. The rotating shaft 130 is slidably matched with the sliding frame 160.

[0064] The turntable 140 has a first rotation stop point, a second rotation stop point, and a third rotation stop point. When the turntable 140 is located at the first rotation stop point, the sampling end of the sampling tube 150 is accommodated in the extended guide section 123. When the turntable 140 is located at the second rotation stop point, the length of the sampling tube 150 extending through the guide sleeve 120 reaches a maximum value. When the turntable 140 is located at the third rotation stop point, the sampling end of the sampling tube 150 retracts to the extended guide section 123.

[0065] Through the above design, the rotating disk 140 is rotated from the first rotation stop point to the second rotation stop point, and the extension amount of the sampling tube 150 reaches the maximum value, and the sample has been obtained in the sampling tube 150. The rotating disk 140 is continued to be rotated, and the rotating disk 140 is rotated from the second rotation stop point to the third rotation stop point, and the sampling tube 150 is retracted again, and the sampling end of the sampling tube 150 is retracted to the extension guide section 123. At this time, the sliding frame 160 is slid to remove the sliding frame 160 from the outer tube 110, and the inner core can be taken out, and the sampling tube 150 is separated from the extension guide section 123 along the axial direction of the outer tube 110. After replacing the new sampling tube 150, the sliding frame 160 is reinstalled on the outer tube 110, and the sampling tube 150 is re-matched to the extension guide section 123, and the inner core is reassembled.

[0066] In order to improve the accuracy of assembly, the guide sleeve 120 is universally hinged to the outer tube 110 with damping.

[0067] It should be noted that the turntable 140 of the inner core can be arranged in multiple groups, and the multiple groups of turntables 140 are arranged at intervals along the axial direction of the rotating shaft 130. Each turntable 140 is equipped with a sampling tube 150, and each sampling tube 150 is correspondingly provided with a sampling port. Along the circumference of the outer tube 110, the sampling ports corresponding to the sampling tubes 150 of all turntables 140 are staggered. To ensure that when the inner core is removed by sliding the sliding member, the guide sleeves 120 corresponding to different sampling tubes 150 will not interfere with the removal work. In this embodiment, there are four groups of turntables 140. Four groups of turntables 140 are arranged at intervals along the axial direction of the rotating shaft 130. The sampling tubes of two adjacent groups of turntables are staggered by 90° along the circumference of the outer tube.

[0068] In this embodiment, the inner core further comprises a reinforcing plate 170, which is fixedly connected to the sliding frame 160, and the rotating shaft 130 passes through the reinforcing plate 170 and is rotatably matched with the reinforcing plate 170. The reinforcing plate 170 is provided with a clearance notch 171 for making way for the guide sleeve 120 and the extended guide section 123.

[0069] It should be noted that the biochar of the adsorption layer 400 can be in granular form or powdered form. In this embodiment, powdered biochar is used. In addition, the rotating shaft 130 extends all the way to the top of the sampling column 100 and extends to the outside of the outer tube 110. In order to facilitate the rotation of the rotating shaft 130, a rotating hand wheel is configured at the end of the rotating shaft 130. Of course, a driving motor, such as a servo motor, can also be configured to drive the rotating shaft 130 to rotate.

[0070] In specific applications, the biochar landfill layer structure 1000 is more suitable for the optimization treatment of shallow soil (such as cultivated soil), wherein the adsorption layer 400 can be completely composed of biochar or a mixture of biochar and cultivated soil.

[0071] This embodiment also provides a method for monitoring Cd adsorption using the biochar landfill layer structure 1000 for adsorbing Cd, which includes: driving the rotating shaft 130 to rotate in a directional manner to complete sampling. Pulling out the sampling column 100 to take out the sample. The specific operation steps have been described in detail above and will not be repeated here.

[0072] The sample taken out can be analyzed by the following method to evaluate the adsorption effect and adsorption amount of Cd, so as to decide whether to replace the adsorption layer 400 or optimize the adsorption capacity of the adsorption layer 400 according to the result. The specific method can be: using an atomic absorption spectrophotometer to detect the amount of Cd absorbed by a unit weight of the sample.

[0073] If the amount of Cd adsorbed per unit weight of the samples obtained at different sampling points is basically the same, it indicates that the adsorption capacity of the adsorption layer 400 is relatively balanced and the overall adsorption capacity is well exerted. If the amount of Cd adsorbed per unit weight of the samples obtained at different sampling points is greatly different, it indicates that the adsorption effect of the adsorption layer 400 is greatly different at different positions. There are two main reasons for this situation:

[0074] 1. Peripheral adsorption takes precedence. The characteristic of this situation is that the adsorption amount of each point in the outer layer is basically the same when sampling along the outer layer of the adsorption layer 400, while the adsorption amount of the inner layer is less than that of the outer layer. This is mainly because the outer layer is closer to the external Cd, and the outer layer takes precedence over the inner layer, and the outer layer is adsorbed first. This situation generally does not require special treatment and is normal. Just continue to monitor the adsorption situation.

[0075] 2. The overall setting of the adsorption layer 400 is unreasonable. This situation is characterized by a large difference in the amount of adsorption between various points in the outer layer, which is generally caused by the adsorption layer 400 itself. For example: (1) the adsorption layer 400 is not filled sufficiently and the density is not enough, resulting in different adsorption effects at different positions; (2) the biochar in the adsorption layer is unevenly distributed; (3) the contact effect between the adsorption layer 400 and the surrounding soil layer is not good, etc. At this time, it is generally necessary to optimize the adsorption layer 400 to eliminate the above problems.

[0076] In summary, the biochar landfill layer structure 1000 for adsorbing Cd has a simple structure, is easy to implement, and has low implementation difficulty. It can effectively and continuously improve the soil, adsorb Cd in the soil, and effectively remove Cd in the soil, which helps to continuously improve the soil quality and improve the quality of crops. In addition, it is easy to monitor and control, and can very conveniently evaluate the adsorption situation, which is convenient for subsequent maintenance and continuous optimization, and has positive significance for continuously improving the adsorption effect. The Cd adsorption monitoring method is simple to operate and easy to implement, and can very conveniently sample the adsorption layer 400, which has positive significance for continuously monitoring and optimizing the adsorption effect.

[0077] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A biomass carbon landfill structure for adsorbing Cd, characterized in that: include: A sampling column, and a first base layer, a second base layer, an adsorption layer, a first covering layer and a second covering layer arranged in sequence from bottom to top; the first base layer and the first covering layer are both composed of gravel, the second base layer is composed of mud and sand, the second covering layer is a soil layer, and the adsorption layer is composed of biomass charcoal; the sampling column penetrates the adsorption layer; The sampling column comprises an outer tube and an inner core, wherein the inner core comprises a rotating shaft, a rotating disk and a sampling tube; the rotating shaft is rotatably arranged in the tube cavity of the outer tube and arranged along the length direction thereof, and the rotating disk is fixedly connected to the rotating shaft; the tail end of the sampling tube is hinged to the disk surface of the rotating disk; The outer tube wall is provided with a sampling port for the sampling tube to extend out, and the sampling end of the sampling tube can be slidably matched with the sampling port; the rotating shaft is used to drive the rotating disk to rotate, so that the sampling tube can extend out of the sampling port and retract as the rotating disk further rotates, thereby completing the sampling; The sampling port is provided with a guide sleeve, the guide sleeve is universally rotatably arranged at the sampling port, and the sampling tube is slidably matched with the guide sleeve; The guide sleeve is spherical and can be universally rotatably embedded in the sampling port; the guide through hole of the guide sleeve is arranged along its radial direction, and a rubber ring is accommodated at the outer end of the guide through hole, and the rubber ring is arranged in contact with the hole wall of the guide through hole and extends in a ring shape along the circumference of the guide through hole; the sampling tube is interference fit with the rubber ring and can slide; The guide sleeve also has an extended guide section, which is connected to its outer wall and arranged along its radial direction, and has a guide slide groove for accommodating the sampling tube, and the guide slide groove is connected to the guide through hole; along the axial direction of the guide through hole, the sampling tube is slidably matched with the guide slide groove; The cross section of the extended guide section is in the shape of a fan ring, and the groove wall of the guide groove and the hole wall of the guide through hole are located on the same cylindrical surface; A stopper is provided at the end of the sampling end of the sampling tube, one end of the stopper is connected to the end wall of the sampling tube, and the other end extends toward the tail end of the sampling tube and toward the central axis of the sampling tube; the stopper is continuously arranged in a ring shape along the circumference of the sampling tube; The inner core also includes a sliding frame; along the axial direction of the outer tube, the sliding frame is slidably matched with the inner wall of the outer tube; along the circumferential direction of the outer tube, the sliding frame is fixedly matched with the inner wall of the outer tube; the rotating shaft is slidably matched with the sliding frame; the turntable has a first rotation stop point, a second rotation stop point and a third rotation stop point; when the turntable is located at the first rotation stop point, the sampling end of the sampling tube is accommodated in the extended guide section; when the turntable is located at the second rotation stop point, the extended length of the sampling tube through the guide sleeve reaches a maximum value; when the turntable is located at the third rotation stop point, the sampling end of the sampling tube retracts to the extended guide section.

2. The biomass carbon landfill structure for adsorbing Cd according to claim 1, characterized in that: The inner core has multiple groups of turntables, which are spaced apart along the axial direction of the rotating shaft; each turntable is provided with the sampling tube, and each sampling tube is provided with the sampling port; along the circumference of the outer tube, the sampling ports corresponding to the sampling tubes of all the turntables are staggered.

3. The biomass carbon landfill structure for adsorbing Cd according to claim 2, characterized in that: The inner core also has a reinforcing plate, which is fixedly connected to the sliding frame, and the rotating shaft passes through the reinforcing plate and is rotatably matched with the reinforcing plate.

4. A method for monitoring Cd adsorption using the biochar landfill structure for adsorbing Cd as claimed in any one of claims 1 to 3, characterized in that: include: The rotating shaft is driven to rotate in a directional manner to complete sampling; the sampling column is pulled out to take out the sample.

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