Complete equipment and process method for extracting and solidifying soil heavy metals by utilizing plants

Abstract

The invention belongs to the technical field of heavy metal extraction, and particularly relates to complete equipment for extracting and solidifying soil heavy metal through plants and a technological method.The complete equipment comprises a main furnace body and a first-stage collector, the first-stage collector is connected with the main furnace body through a pipeline, a second-stage collector is connected with the first-stage collector through a pipeline, and the second-stage collector is connected with the second-stage collector through a pipeline; according to the invention, heavy metals are extracted and separated from plants by adopting special processes such as metal smelting and the like, meanwhile, the plants are subjected to preheating, high-temperature cracking and high-temperature activation in the process of extracting the heavy metals by high-temperature carbonization to form high-temperature biochar, and the high-temperature biochar is rich in pores and is used as a curing agent for soil heavy metals; the pollution to plants is reduced by stable solidification, so that heavy metals are continuously extracted from the plants including various straws, meanwhile, high-temperature biochar is formed as a heavy metal curing agent after high-temperature processing and heavy metal separation of the plants, and the problem of heavy metal pollution of large-area soil can be rapidly solved by repeated utilization.

Description

Technical Field

[0001] This invention relates to the field of heavy metal extraction technology, specifically to a complete set of equipment and processes for extracting and solidifying heavy metals from soil using plants. Background Technology

[0002] Soil is one of the most fundamental material foundations for human survival and the ultimate destination of various pollutants; 90% of the world's pollutants ultimately remain in the soil. Because heavy metal pollution has poor mobility and long retention time in soil, it cannot be degraded by microorganisms and may ultimately affect human health through water, plants, and other media. Therefore, it is necessary to take measures to remediate heavy metal-contaminated soil. According to relevant surveys and studies, approximately 20% of my country's soil is currently severely polluted by heavy metals, with unimaginable consequences. Furthermore, my country's agricultural grain output is declining sharply at a rate of 10 million tons per year, with tens of millions of tons of grain affected by heavy metal contamination, directly leading to significant economic losses.

[0003] Currently, the remediation of soil heavy metal pollution mainly falls into three categories: physical methods, chemical methods, and biological methods (examples are given to illustrate the advantages and disadvantages of each method): physical method Soil replacement and soil exchange methods: These mainly include deep plowing, soil exchange, and soil replacement. Deep plowing is used when the soil is only slightly polluted, while soil replacement is used when treating heavily polluted areas. Soil replacement is very effective in remediating heavy metal pollution in soil, but its disadvantages are that it involves a large amount of engineering work, high investment, and can easily cause problems such as a decline in soil fertility.

[0004] Chemical method (chemical curing method) The primary impact of heavy metals on soil lies in their mobility. The form in which heavy metals exist in soil determines their mobility. Soil properties such as pH and EH values ​​can influence the form in which heavy metals exist, and these parameters can be used to regulate their mobility. Chemical solidification of heavy metals reduces their mobility through adsorption or precipitation. Fixing heavy metals in soil reduces pollution of deeper soil layers and groundwater. However, a drawback is that it doesn't fundamentally solve the problem of separating and removing heavy metals from soil. Saturated solidification agents may fail to adsorb heavy metals, leaving them still in the soil.

[0005] Microbial remediation Microbial remediation is a bioremediation technology that utilizes naturally occurring or cultured functional microbial communities under suitable environmental conditions to promote or enhance microbial metabolic functions, thereby reducing toxic pollutants or degrading them into non-toxic substances. The essence of microbial remediation is biodegradation, that is, the decomposition of environmental pollution by microorganisms. However, the living conditions of microorganisms in contaminated soil are often quite harsh, making it challenging to artificially modify and optimize the microbial environment to achieve this.

[0006] The above examples illustrate three methods, including isolation, thermal methods, chemical solidification, soil leaching, biological methods, phytoremediation, and microbial remediation, but none of them fundamentally remove heavy metals from the soil. Therefore, this invention aims to develop a complete set of equipment and processes for extracting and solidifying heavy metals from soil using plants. Summary of the Invention

[0007] In view of the problems existing in the above and / or the existing complete set of equipment and process methods for extracting and solidifying heavy metals in soil using plants, the present invention is proposed.

[0008] Therefore, the purpose of this invention is to provide a complete set of equipment and process for extracting and solidifying heavy metals from soil using plants, which can solve the aforementioned existing problems.

[0009] To address the aforementioned technical problems, according to one aspect of the present invention, the present invention provides the following technical solution: A complete set of equipment for extracting and solidifying heavy metals from soil using plants, comprising: main furnace body; A primary collector, which is connected to the main furnace body via a pipe; A secondary collector, which is connected to the primary collector via a pipe; A three-stage condenser collector, which is connected to the two-stage collector via a pipeline; An emission purification device is provided, which is connected to the three-stage condenser via a pipeline.

[0010] As a preferred embodiment of the complete set of equipment for extracting and solidifying heavy metals from soil using plants as described in this invention, the top of the main furnace body is provided with a combustion explosion-proof device, and the side wall of the main furnace body is provided with an oxygen supply control device.

[0011] As a preferred embodiment of the complete set of equipment for extracting and solidifying heavy metals from soil using plants as described in this invention, the main furnace body is provided with a multi-layer combustion device in the middle, and the main furnace body is provided with a three-section combustion device in the middle, and the three-section combustion device is provided with a multi-layer combustion device.

[0012] As a preferred embodiment of the complete set of equipment for extracting and solidifying heavy metals from soil using plants as described in this invention, the three-section combustion device consists of a preheating zone, a carbonization and pyrolysis zone, and a high-temperature activation zone, which are arranged sequentially from top to bottom.

[0013] As a preferred embodiment of the complete set of equipment for extracting and solidifying heavy metals from soil using plants as described in this invention, the top of the primary collector is provided with a high-pressure nozzle, and the top of the primary collector is provided with an atomizer, which is located directly below the high-pressure nozzle.

[0014] As a preferred embodiment of the complete set of equipment for extracting and solidifying heavy metals from soil using plants as described in this invention, wherein: the middle of the primary collector is provided with an atomization chamber, and the bottom of the primary collector is provided with a sedimentation chamber.

[0015] As a preferred embodiment of the complete set of equipment for extracting and solidifying heavy metals in soil using plants as described in this invention, the secondary collector has a first spray device at the top, a baffle separation device at the middle, and a first collection and storage device at the bottom.

[0016] As a preferred embodiment of the complete set of equipment for extracting and solidifying heavy metals from soil using plants as described in this invention, the three-stage condenser is provided with a second spray device at the top, a first baffle at the top, a second baffle at the middle, a third baffle at the bottom, and several pipes between the third baffle and the second baffle. The bottom of the three-stage condenser is provided with a second collection and storage device.

[0017] As a preferred embodiment of the complete set of equipment for extracting and solidifying heavy metals from soil using plants as described in this invention, the emission purification device includes: A water vapor separator, wherein the water vapor separator is connected to the three-stage condenser collector via a pipeline; A flue gas separator and purifier, wherein the flue gas separator and purifier are connected to the water vapor separator via a pipeline, and an exhaust fan is provided between the water vapor separator and the flue gas separator and purifier.

[0018] A process for extracting and solidifying heavy metals from soil using plants includes the following specific steps: Step 1: The main furnace body causes metallic cadmium to form a gaseous state, which is then separated from the biochar. At the same time, the biochar is activated at high temperature, and some low-temperature non-combustible organic matter is burned at high temperature to form biochar with rich pores. Step 2: Various gaseous substances formed by high-temperature carbonization in the main furnace are atomized, cooled, and solidified through a primary collector, changing from gaseous to liquid and then to solid, and then collected and stored in the sedimentation chamber. Step 3: The heavy metal dust particles, some of which are small particles, carried out by the primary collector are collected and treated again by the secondary collector. Step 4: The liquid and mixture collected after the first and second collections are water-cooled and collected again through a three-stage condenser to prevent the loss of heavy metals and environmental pollution. Step 5: Treat the flue gas and water vapor in the pipeline through the emission purification device. Purify the gas through the water vapor separator and the flue gas separator and purifier, and finally the emission meets the standards.

[0019] Compared with existing technologies: This invention employs special processes such as metal smelting to extract and separate heavy metals from plants. During the high-temperature carbonization extraction process, the plant body undergoes preheating, combustion, and high-temperature activation to form high-temperature biochar. Due to its rich pores, the high-temperature biochar is used as a solidifying agent for heavy metals in the soil, stabilizing and solidifying them to reduce pollution to plants. In this way, heavy metals can be continuously extracted from plants, including various straws, while the high-temperature processing of the plant body separates the heavy metals into high-temperature char, which serves as a heavy metal solidifying agent. This repeated use can quickly solve the problem of heavy metal pollution in large areas of soil. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the structure of the present invention; Figure 2 This is a front view schematic diagram of the main furnace body structure of the present invention; Figure 3 This is a front view schematic diagram of the primary collector structure of the present invention; Figure 4 This is a front view schematic diagram of the secondary collector structure of the present invention; Figure 5 This is a front view schematic diagram of the three-stage condenser collector structure of the present invention.

[0021] In the diagram: Main furnace body 10, combustion explosion-proof device 11, oxygen supply control device 12, multi-layer combustion device 13, preheating zone 14, carbonization and pyrolysis zone 15, high-temperature activation zone 16, primary collector 20, high-pressure nozzle 21, atomizer 22, atomization chamber 23, sedimentation chamber 24, secondary collector 30, first spray device 31, baffle separation device 32, first collection and storage device 33, tertiary condenser collector 40, second spray device 41, first baffle 42, second baffle 43, pipe 44, third baffle 45, second collection and storage device 46, water vapor separator 50, induced draft device 60, flue gas separator and purifier 70. Implementation

[0022] To make the objectives, technical solutions, and advantages of the present invention clearer, the embodiments of the present invention will be described in further detail below with reference to the accompanying drawings.

[0023] This invention provides a complete set of equipment for extracting and solidifying heavy metals from soil using plants. Please refer to [link / reference]. Figures 1-5 It includes: main furnace body 10, primary collector 20, secondary collector 30, tertiary condenser collector 40, and emission purification device; The primary collector 20 is connected to the main furnace body 10 via a pipe, the secondary collector 30 is connected to the primary collector 20 via a pipe, the tertiary condenser collector 40 is connected to the secondary collector 30 via a pipe, and the emission purification device is connected to the tertiary condenser collector 40 via a pipe.

[0024] The top of the main furnace body 10 is equipped with a combustion explosion-proof device 11, the side wall of the main furnace body 10 is equipped with an oxygen supply control device 12, the middle of the main furnace body 10 is equipped with a multi-layer combustion device 13, the middle of the main furnace body 10 is equipped with a three-section combustion device, and the three-section combustion device is equipped with a multi-layer combustion device 13. The three-section combustion device consists of a preheating zone 14, a carbonization and pyrolysis zone 15 and a high-temperature activation zone 16, and the preheating zone 14, the carbonization and pyrolysis zone 15 and the high-temperature activation zone 16 are arranged in order from top to bottom. Specifically: Main furnace body 10: Made of 6mm thick steel plate, the inner liner of the furnace is made of refractory material silicon dioxide (resistant to 1700 degrees), and the thickness of the inner liner is not less than 50mm; Combustion explosion-proof device 11: A flue gas explosion-proof valve is installed on the upper part of the burner. When the induced draft fan in the furnace is not running properly, causing a rapid change in the pressure inside the furnace, the explosion-proof device can be automatically opened to achieve the explosion-proof protection function. Oxygen supply control device 12: The furnace body is equipped with multiple gas control devices, each with an air control valve. These devices are adjustable according to operating temperature requirements. A three-zone ring control system is provided, which can adjust the oxygen supply and control the temperature at each stage. The oxygen supply control device 12 is connected to a computer to monitor and adjust the temperature, achieving the desired temperature. Multi-layer combustion device 13: Depending on the requirements, single-layer and multi-layer combustion devices are available. For higher temperature requirements, double-layer or multi-layer combustion devices are used, made of 310S stainless steel. Primarily controls the combustion function within the furnace. Three-zone combustion device: To completely remove heavy metals from plants and obtain high-quality biochar with rich porosity, this device innovatively designs a three-zone combustion process for removing heavy metals within the furnace. The process consists of a material preheating zone, a carbonization and pyrolysis zone, and a high-temperature activation zone. This technology uses high-temperature separation to extract heavy metals. Based on the temperature conversion characteristics of cadmium (melting point 320.9°C, boiling point 765°C), when material containing cadmium enters the preheating zone 14 through the feed inlet to remove moisture, it enters the pyrolysis zone 15, a high-temperature pyrolysis furnace, where the temperature reaches approximately 450-550°C. At temperatures exceeding 320.9°C, the cadmium changes from a solid to a liquid state. During this period, the plant matter undergoes high-temperature pyrolysis to form biochar, which then enters the high-temperature activation zone 16 from the carbonization and pyrolysis zone 15. The temperature rises above 800°C, exceeding 765°C, at which point the cadmium forms a gaseous state and separates from the biochar. Simultaneously, the biochar undergoes high-temperature activation, and some low-temperature non-combustible organic matter is burned at high temperatures to form porous biochar. After the combustible material is fully burned by the dual burners, it, along with the gaseous heavy metals, enters the primary collector 20 through pipelines.

[0025] The first-stage collector 20 is provided with a high-pressure nozzle 21 at the top and an atomizer 22 at the top, with the atomizer 22 located directly below the high-pressure nozzle 21. The first-stage collector 20 is provided with an atomization chamber 23 in the middle and a sedimentation chamber 24 at the bottom. Specifically: The primary collector 20 is made of stainless steel and consists of four parts: a high-pressure nozzle, an atomizer, an atomization chamber, and a sedimentation chamber. When a solid is heated, its molecules or atoms gradually increase their kinetic energy, overcoming the attraction and beginning to break away from their tightly packed structure. When the substance reaches its melting point, the solid melts and transforms into a liquid. When the liquid is heated, the kinetic energy of its molecules or atoms further increases, overcoming the internal attraction, and molecules on the liquid surface begin to escape. When the temperature reaches a certain value, the liquid begins to evaporate violently and transforms into a gas. When the gas is cooled, the kinetic energy of its molecules and atoms decreases, and they aggregate to form a liquid. As the liquid continues to cool, the kinetic energy of its molecules or atoms further decreases, and the attraction gradually becomes dominant, causing the liquid molecules to rearrange into a tightly ordered structure. When the liquid reaches its freezing point, the liquid transforms into a solid. Based on the solid-liquid-gas transformation law, this collector utilizes a specially designed water-gas sealing atomization water cooling process to transform the high-temperature gas into a liquid, then from a liquid into a solid, and finally into the sedimentation chamber of the collector for collection.

[0026] The secondary collector 30 has a first spray device 31 at the top, a baffle separation device 32 in the middle, and a first collection and storage device 33 at the bottom. The baffle separation device 32 has the function of adsorbing and filtering particulate heavy metals and mixed gas. Specifically: The secondary collector 30 is made of stainless steel and uses a multi-layer baffle-type purification device. It mainly treats some small particulate metals and mixed gas impurities carried out by the flue gas duct after the primary collection by adsorption, filtration and spraying, so as to recycle the small particulate heavy metals.

[0027] The top of the three-stage condenser 40 is provided with a second spray device 41, the top of the three-stage condenser 40 is provided with a first baffle 42, the middle of the three-stage condenser 40 is provided with a second baffle 43, the bottom of the three-stage condenser 40 is provided with a third baffle 45, and a plurality of pipes 44 are provided between the third baffle 45 and the second baffle 43. The bottom of the three-stage condenser 40 is provided with a second collection and storage device 46. Specifically: The three-stage condenser collector 40 is made of multi-tube stainless steel and is used in conjunction with the cooling tower. After the first and second collection of cold water purification, the liquid and mixture are collected and purified again by water cooling to prevent the loss of heavy metals and other harmful substances and environmental pollution.

[0028] The emission purification device includes: a water vapor separator 50 and a flue gas separator 70; The water vapor separator 50 is connected to the three-stage condenser collector 40 through a pipeline, and the flue gas separator 70 is connected to the water vapor separator 50 through a pipeline. An exhaust fan 60 is provided between the water vapor separator 50 and the flue gas separator 70. Specifically: The emission purification device mainly treats flue gas and water vapor in the pipeline. It purifies the gas through a water vapor separator and a flue gas separator and purifier, and finally the emissions meet the standards.

[0029] A process for extracting and solidifying heavy metals from soil using plants includes the following specific steps: Step 1: The main furnace body 10 causes metallic cadmium to form a gaseous state, which is separated from the biochar. At the same time, the biochar is activated at high temperature, and some low-temperature non-combustible organic matter is burned at high temperature to form biochar with rich pores. Step 2: The various gaseous substances formed by high-temperature carbonization in the main furnace body 10 are atomized, cooled, and solidified through the primary collector 20, changing from gaseous to liquid and then to solid, and then collected and stored in the sedimentation chamber. Step 3: The secondary collector 30 performs secondary collection and treatment on some of the fine heavy metal dust particles carried out by the primary collector 20. Step 4: The liquid and mixture collected after the first and second collections are subjected to water cooling treatment through a three-stage condenser collector 40 to collect and purify them again, in order to prevent the loss of heavy metal substances and environmental pollution. Step 5: The flue gas and water vapor in the pipeline are treated by the emission purification device. The water vapor separator 50 and the flue gas separator purifier 70 are used for purification treatment, and finally the emission meets the standards.

[0030] This complete set of equipment is generally installed with two furnace bodies connected as a group, or four furnace bodies connected as a group. That is to say, the complete set of equipment for extracting and solidifying heavy metals from soil using plants can be equipped with two furnace bodies or four furnace bodies as a group. Alternatively, it can be equipped with one furnace body, depending on the material. If there is a lot of material and a large production capacity is required, a multi-furnace combination can be used.

[0031] The key features of this process are: gasification at this temperature allows for the simultaneous separation of heavy metals such as cadmium, lead, and mercury. The resulting biochar is not only completely free of heavy metals but also exhibits significantly enhanced activity, approaching that of activated carbon. It can be widely used in fertilizers, soil conditioners, and other products.

[0032] Although the present invention has been described above with reference to embodiments, various modifications can be made and components can be replaced with equivalents without departing from the scope of the invention. In particular, as long as there is no structural conflict, the features in the disclosed embodiments can be combined with each other in any manner. The lack of an exhaustive description of these combinations in this specification is merely for the sake of brevity and resource conservation. Therefore, the present invention is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A complete set of equipment for extracting and solidifying heavy metals from soil using plants, characterized in that, include: Main furnace body (10); A primary collector (20) is connected to the main furnace body (10) via a pipe; A secondary collector (30) is connected to the primary collector (20) via a pipe; A three-stage condenser collector (40) is connected to the two-stage collector (30) via a pipeline; The emission purification device is connected to the three-stage condenser (40) via a pipeline.

2. The complete set of equipment for extracting and solidifying heavy metals from soil using plants according to claim 1, characterized in that, The top of the main furnace body (10) is provided with a combustion explosion-proof device (11), and the side wall of the main furnace body (10) is provided with an oxygen supply control device (12).

3. The complete set of equipment for extracting and solidifying heavy metals from soil using plants according to claim 2, characterized in that, The main furnace body (10) is provided with a multi-layer combustion device (13) in the middle, and a three-section combustion device is provided in the middle of the main furnace body (10), and the multi-layer combustion device (13) is provided in the three-section combustion device.

4. The complete set of equipment for extracting and solidifying heavy metals from soil using plants according to claim 3, characterized in that, The three-section combustion device consists of a preheating zone (14), a carbonization and pyrolysis zone (15), and a high-temperature activation zone (16), which are arranged sequentially from top to bottom.

5. The complete set of equipment for extracting and solidifying heavy metals from soil using plants according to claim 1, characterized in that, The top of the primary collector (20) is provided with a high-pressure nozzle (21) and an atomizer (22) is provided at the top of the primary collector (20), and the atomizer (22) is located directly below the high-pressure nozzle (21).

6. A complete set of equipment for extracting and solidifying heavy metals from soil using plants according to claim 5, characterized in that, The primary collector (20) has an atomization chamber (23) at its middle end and a sedimentation chamber (24) at its bottom end.

7. The complete set of equipment for extracting and solidifying heavy metals from soil using plants according to claim 1, characterized in that, The secondary collector (30) has a first spray device (31) at the top, a baffle removal device (32) at the middle, and a first collection storage device (33) at the bottom.

8. A complete set of equipment for extracting and solidifying heavy metals from soil using plants according to claim 1, characterized in that, The top of the three-stage condenser (40) is provided with a second spray device (41), the top of the three-stage condenser (40) is provided with a first baffle (42), the middle of the three-stage condenser (40) is provided with a second baffle (43), the bottom of the three-stage condenser (40) is provided with a third baffle (45), and a plurality of pipes (44) are provided between the third baffle (45) and the second baffle (43). The bottom of the three-stage condenser (40) is provided with a second collection and storage device (46).

9. A complete set of equipment for extracting and solidifying heavy metals from soil using plants according to claim 1, characterized in that, The emission purification device includes: A water vapor separator (50) is connected to the three-stage condenser collector (40) via a pipeline; A flue gas separator (70) is provided, which is connected to the water vapor separator (50) through a pipe, and an exhaust fan (60) is provided between the water vapor separator (50) and the flue gas separator (70).

10. A process for extracting and solidifying heavy metals from soil using plants, characterized in that, The specific steps are as follows: Step 1: The main furnace body (10) causes the metallic cadmium to form a gaseous state and separate it from the biochar. At the same time, the biochar is activated at high temperature and some low-temperature non-combustible organic matter is burned at high temperature to form biochar with rich pores. Step 2: The various gaseous substances formed by high-temperature carbonization in the main furnace body (10) are atomized, cooled and solidified through the primary collector (20), changing from gaseous to liquid and then to solid, and then collected and stored in the sedimentation chamber; Step 3: The heavy metal dust particles that are carried out by the primary collector (20) are collected and treated in a secondary manner by the secondary collector (30); Step 4: The liquid and mixture collected after the first and second collections are water-cooled and collected again through a three-stage condenser (40) to prevent the loss of heavy metal substances and pollution of the environment. Step 5: The flue gas and water vapor in the pipeline are treated by the emission purification device. The water vapor separator (50) and flue gas separator (70) are used for purification treatment, and finally the emission meets the standards.

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