Contaminated soil in-situ thermal desorption treatment heat supply device

Abstract

The utility model relates to the technical field of soil remediation, and particularly discloses a polluted soil in-situ thermal desorption treatment heat supply device which comprises a flue and a plurality of heating wells, one end of the flue is closed, the other end of the flue is connected with a heating furnace, the heating furnace is communicated with a discharge pipe, an exhaust fan is arranged on the discharge pipe, and a backflow air valve is arranged at an air outlet of the exhaust fan. The heating well comprises a combustor, a well head and a heating pipe, the combustor is provided with a natural gas inlet pipe and an air inlet pipe, the combustor and the heating pipe are both communicated with the well head, the heating pipe is buried underground, the lower end of the heating pipe is closed, and a smoke exhaust branch pipe is arranged on the heating pipe and communicated with the flue. Through reasonable temperature control and energy utilization, the problem of non-uniform temperature distribution in the soil remediation process is effectively solved, and uniform heating and effective treatment of the whole remediation area are ensured.

Description

Technical Field

[0001] The utility model belongs to the technical field of soil remediation, and in particular relates to an in-situ thermal desorption treatment and heating device for contaminated soil. Background Art

[0002] In recent years, the rapid development of the industrial economy has also triggered many environmental pollution incidents. Frequent leakage and illegal discharge of industrial products, waste materials, waste liquids, etc. have caused the soil in the original factory area to be polluted to varying degrees. In particular, sites contaminated by highly mobile and highly toxic volatile or semi-volatile organic compounds have attracted much attention. In order to treat these contaminated sites, a variety of remediation technologies have been applied.

[0003] Soil thermal desorption remediation technology is a remediation method for organic contaminated sites, which mainly includes two categories: ex situ thermal desorption and in situ thermal desorption. Ex situ thermal desorption refers to extracting the soil and placing it in a thermal desorption system for treatment; while in situ thermal desorption refers to heating the soil for thermal desorption without changing its position.

[0004] The in-situ thermal desorption system mainly uses heat conduction heating technology to heat the contaminated soil to above the boiling point of the target pollutant. By controlling the system temperature and material residence time, it selectively promotes the gasification and volatilization of pollutants, separates and removes the target pollutants from soil particles, thereby achieving the purpose of soil remediation.

[0005] In the in-situ thermal desorption system, due to the thermal radiation of the heating well and the heat conduction of the soil, a radiation gradient area with the heating well as the core and the soil temperature from high to low is formed. Therefore, the area near the heating well has a better heating effect, while the soil farther away heats up slowly. In order to desorb organic pollutants, a large amount of energy needs to be continuously provided to heat the site, which leads to relatively high energy consumption and cost of thermal conduction heating technology. In addition, in actual soil remediation operations, some areas with lower temperatures are often encountered, reflecting that the temperature distribution on site is uneven and the heating system is not perfect, which needs further improvement.

[0006] Therefore, we propose an in-situ thermal desorption treatment heating device for contaminated soil to solve the above technical problems. Utility Model Content

[0007] In order to solve the technical problems existing in the above-mentioned prior art, the utility model proposes an in-situ thermal desorption treatment and heating device for contaminated soil.

[0008] The technical solution adopted by the utility model is as follows:

[0009] A heating device for in-situ thermal desorption treatment of contaminated soil, comprising a flue and multiple heating wells, wherein one end of the flue is closed and the other end is connected to a heating furnace, the heating furnace is connected to an exhaust pipe, the exhaust pipe is provided with an exhaust fan, and a return air valve is provided at the air outlet of the exhaust fan, the heating well comprises a burner, a wellhead and a heating pipe, the burner is provided with a natural gas inlet pipe and an air inlet pipe, the burner and the heating pipe are both connected to the wellhead, the heating pipe is buried underground and the lower end is closed, the heating pipe is provided with a smoke exhaust branch pipe, and the smoke exhaust branch pipe is connected to the flue.

[0010] In a further technical solution, the heating wells are evenly arranged on both sides of the flue along the radial direction of the flue.

[0011] In a further technical solution, a temperature measuring instrument is provided at a position of the smoke exhaust branch pipe close to the heating pipe.

[0012] In a further technical solution, the temperature measuring instrument adopts a PT100 thermocouple.

[0013] In a further technical solution, the heating pipe includes a heating inner pipe and a heating outer pipe, the heating inner pipe is connected to the wellhead, the heating outer pipe is sleeved on the outside of the heating inner pipe and the end is closed, and the smoke exhaust branch pipe is arranged on the heating outer pipe.

[0014] In a further technical solution, the air inlet pipe is connected to an extension pipe, and the extension pipe is connected to a combustion-supporting fan.

[0015] In a further technical solution, a manual air regulating valve is provided on the smoke exhaust branch pipe.

[0016] In a further technical solution, the outer sides of the flue, the exhaust pipe, the heating pipe and the smoke exhaust branch pipe are all provided with insulation materials, and the outer sides of the insulation materials are provided with galvanized steel plates.

[0017] In summary, due to the adoption of the above technical solution, the beneficial effects of the utility model are:

[0018] 1. The utility model effectively solves the problem of uneven temperature distribution in the soil remediation process through reasonable temperature control and energy utilization, ensuring uniform heating and effective treatment of the entire remediation area.

[0019] 2. The utility model not only improves the utilization rate of fuel but also further utilizes thermal energy through secondary combustion treatment and hot air reflow, effectively reducing energy consumption and use costs.

[0020] 3. The utility model adopts a double-layer structure design of a heating inner tube and a heating outer tube. The heating inner tube is used for the entry of high-temperature flue gas, and the heating outer tube is used for the discharge of high-temperature flue gas. This makes the entry and discharge of high-temperature flue gas flow more stable, avoids mutual interference when the high-temperature flue gas enters and discharges, and is convenient for use. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The present invention will be described by way of examples with reference to the accompanying drawings, in which:

[0022] Figure 1 It is a structural schematic diagram of the utility model;

[0023] Figure 2 It is a structural schematic diagram of the heating well of the utility model.

[0024] Figure markings: 1-flue, 2-heating well, 3-heating furnace, 4-discharge pipe, 5-exhaust fan, 6-return air valve, 7-burner, 8-wellhead, 9-heating pipe, 901-heating inner pipe, 902-heating outer pipe, 10-natural gas inlet pipe, 11-air inlet pipe, 12-smoke exhaust branch pipe, 13-extension pipe, 14-combustion-supporting fan, 15-manual air regulating valve. DETAILED DESCRIPTION

[0025] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0026] Example:

[0027] See also Figure 1 and Figure 2 The present embodiment provides a contaminated soil in-situ thermal desorption treatment heating device, comprising a flue 1 and twenty heating wells 2 uniformly arranged on both sides of the flue 1 along the radial direction of the flue 1, one end of the flue 1 is closed, and the other end is connected to a heating furnace 3, the heating furnace 3 is connected to an exhaust pipe 4, the exhaust pipe 4 is provided with an exhaust fan 5, and the exhaust fan 5 is provided with a return air valve 6 at the air outlet, the heating well 2 comprises a burner 7, a wellhead 8 and a heating pipe 9, the burner 7 is provided with a natural gas inlet pipe 10 and an air inlet pipe 11, the burner 7 and the heating pipe 9 are both connected to the wellhead 8, the heating pipe 9 is buried underground and the lower end is closed, the heating pipe 9 is provided with a smoke exhaust branch pipe 12, and the smoke exhaust branch pipe 12 is connected to the flue 1.

[0028] When conducting in-situ thermal desorption treatment of contaminated soil, the heating device is installed in the contaminated soil area, wherein twenty heating wells 2 are evenly arranged on both sides of the flue 1 radially to ensure that the entire area to be treated is covered, and then the natural gas inlet pipe 10 and the air inlet pipe 11 of the burner 7 are supplied with combustion materials to ensure that the burner 7 can obtain sufficient natural gas and combustion-supporting air. High-temperature flue gas is generated by combustion in the burner 7, and the high-temperature flue gas enters the heating tube 9 from the wellhead, and heats the soil around the heating tube 9 through thermal radiation. Since multiple heating wells 2 are evenly arranged, the heating is more evenly supplied, so that the heating rate in the entire contaminated area is improved, and the soil is effectively heated to above the boiling point of the target pollutants, so that the pollutants are gasified and volatilized, thereby improving the efficiency of thermal desorption treatment and achieving a good soil remediation effect. After the high-temperature flue gas is heat exchanged, it enters the flue 1 through the exhaust branch pipe 12, and is subjected to secondary combustion treatment by the heating furnace 3. The gas is further discharged through the exhaust fan 5, and the return air valve 6 is adjusted to ensure that the high-temperature flue gas can flow back to the heating furnace 3. In this process, through secondary combustion treatment and hot air return, not only the fuel utilization rate is improved, but also the thermal energy is further utilized, effectively reducing energy consumption and use costs. Through reasonable temperature control and energy utilization, the problem of uneven temperature distribution in the soil remediation process is effectively solved, ensuring uniform heating and effective treatment of the entire remediation area.

[0029] In a specific embodiment, a temperature measuring instrument is provided at a position of the smoke exhaust branch pipe 12 close to the heating pipe 9 .

[0030] Specifically, by connecting the temperature measuring instrument to the centralized control box to display the temperature, accurate temperature control and management can be achieved, ensuring the efficiency, safety and energy saving of the heating process, thereby improving the overall effect of in-situ thermal desorption treatment of contaminated soil.

[0031] In a specific implementation, the temperature measuring instrument uses a PT100 thermocouple.

[0032] Specifically, the PT100 thermocouple can work stably in a high temperature environment and is suitable for the high temperature conditions required in the soil thermal desorption process. It has high accuracy and fast response speed, which can make temperature data easier to process and analyze, and help optimize the heating process.

[0033] In a specific embodiment, see Figure 2 The heating tube 9 includes a heating inner tube 901 and a heating outer tube 902 . The heating inner tube 901 is connected to the wellhead 8 . The heating outer tube 902 is sleeved on the outer side of the heating inner tube 901 and has a closed end. The smoke exhaust branch pipe 12 is arranged on the heating outer tube 902 .

[0034] Specifically, by adopting a double-layer structure design of a heating inner tube 901 and a heating outer tube 902, the heating inner tube 901 is used for the entry of high-temperature flue gas, and the heating outer tube 902 is used for the discharge of high-temperature flue gas, so that the flow of the entering and discharged high-temperature flue gas is smoother, avoiding mutual interference when the high-temperature flue gas enters and discharges, and is convenient for use.

[0035] In a specific embodiment, see Figure 2 The air inlet pipe 11 is connected to an extension pipe 13 , and the extension pipe 13 is connected to a combustion-supporting fan 14 .

[0036] Specifically, the combustion-supporting blower 14 provides sufficient air to the burner 7 through the extension pipe 13, ensuring that the natural gas and the air are fully mixed, thereby improving the combustion efficiency.

[0037] In a specific embodiment, see Figure 2 The smoke exhaust branch pipe 12 is provided with a manual air regulating valve 15.

[0038] Specifically, the manual air regulating valve 15 can accurately control the air flow in the smoke exhaust branch pipe 12, adjust the emission speed and amount of high-temperature smoke, help optimize the heat distribution during the heating process, and improve the heating efficiency of the heating device.

[0039] In a specific embodiment, the flue 1, the exhaust pipe 4, the heating pipe 9 and the smoke exhaust branch pipe 12 are all provided with insulation materials on the outside, and the insulation materials are provided with galvanized steel plates on the outside.

[0040] Specifically, the thermal insulation material can reduce heat loss, make the heating device have higher energy efficiency, and provide stable and continuous heating effect, while the galvanized steel plate can effectively protect the thermal insulation material and pipeline, and increase the service life of the equipment.

[0041] In a specific embodiment, the thermal insulation material is aluminum silicate wool.

[0042] Specifically, aluminum silicate wool has excellent thermal isolation effect, is light in weight, has good mechanical strength, and is resistant to high temperatures and corrosion. As a thermal insulation material, it provides a reliable solution for in-situ thermal desorption treatment of contaminated soil.

[0043] The above description is only an embodiment of the present invention, and does not limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made by using the contents of the specification and drawings of the present invention, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A contaminated soil in-situ thermal desorption treatment heating device, characterized in that: The invention comprises a flue (1) and a plurality of heating wells (2) uniformly arranged on both sides of the flue (1) along the radial direction of the flue (1); one end of the flue (1) is closed and the other end is connected to a heating furnace (3); the heating furnace (3) is connected to an exhaust pipe (4); an exhaust fan (5) is provided on the exhaust pipe (4); a return air valve (6) is provided at the air outlet of the exhaust fan (5); the heating well (2) comprises a burner (7), a well head (8) and a heating pipe (9); the burner (7) is provided with a natural gas inlet pipe (10) and an air inlet pipe (11); the burner (7) and the heating pipe (9) are both connected to the well head (8); the heating pipe (9) is buried underground and has a closed lower end; the heating pipe (9) is provided with a smoke exhaust branch pipe (12); the smoke exhaust branch pipe (12) is connected to the flue (1).

2. The in-situ thermal desorption treatment heating device for contaminated soil according to claim 1 is characterized in that: The smoke exhaust branch pipe (12) is provided with a temperature measuring instrument at a position close to the heating pipe (9).

3. The in-situ thermal desorption treatment heating device for contaminated soil according to claim 2 is characterized in that: The temperature measuring instrument adopts PT100 thermocouple.

4. The in-situ thermal desorption treatment heating device for contaminated soil according to claim 1, characterized in that: The heating pipe (9) comprises a heating inner pipe (901) and a heating outer pipe (902); the heating inner pipe (901) is connected to the wellhead (8); the heating outer pipe (902) is sleeved on the outer side of the heating inner pipe (901) and has a closed end; and the smoke exhaust branch pipe (12) is arranged on the heating outer pipe (902).

5. The in-situ thermal desorption treatment heating device for contaminated soil according to claim 1, characterized in that: The air inlet pipe (11) is connected to an extension pipe (13), and the extension pipe (13) is connected to a combustion-supporting fan (14).

6. The in-situ thermal desorption treatment heating device for contaminated soil according to claim 1, characterized in that: The smoke exhaust branch pipe (12) is provided with a manual air regulating valve (15).

7. The in-situ thermal desorption treatment heating device for contaminated soil according to claim 1, characterized in that: The flue (1), the discharge pipe (4), the heating pipe (9) and the smoke exhaust branch pipe (12) are all provided with heat-insulating materials on their outer sides, and the heat-insulating materials are provided with galvanized steel plates on their outer sides.

8. The in-situ thermal desorption treatment heating device for contaminated soil according to claim 7, characterized in that: The thermal insulation material is aluminum silicate wool.

Images