Dust treatment equipment of direct thermal desorption system

Abstract

The utility model relates to the technical field of soil remediation, and particularly discloses direct thermal desorption system dust treatment equipment which mainly comprises a cyclone dust collector, a dust collection chamber, a high-pressure atomization spraying chamber, a double-shaft dust stirrer, a spiral feeder, a double-roller extrusion granulator, a closed conveyor and an automatic control system. After tail gas in the rotary kiln is subjected to cyclone dust removal, large-particle dust is enriched in a dust collection chamber, flows into a high-pressure atomization spraying chamber through an automatic dust discharging valve after a certain amount, enters a double-shaft dust stirrer after being humidified, and is fed to a double-roller extrusion pelletizer through spiral prepressing, so that the dust forms a ball shape; and then the materials are transferred to the feeding hopper through the closed conveyor to be treated again. On one hand, after the dust is humidified, stirred, extruded and granulated, the pollution of the dust to the environment can be reduced. On the other hand, dust does not need to directly return into the kiln, and therefore the overall stability of the system is improved.

Description

Technical Field

[0001] The utility model belongs to the technical field of soil remediation, and particularly relates to a dust treatment device for a direct thermal desorption system. Background Art

[0002] The direct thermal desorption technology is to feed the pretreated contaminated soil into a rotary kiln through a conveyor and a feeding screw after metering, and directly heat the contaminated soil with high-temperature flue gas generated by natural gas combustion in the rotary kiln for thermal desorption treatment, so as to promote the gasification and volatilization of pollutants and the separation from soil particles. At present, after the tail gas in the rotary kiln passes through cyclone dust removal, large-particle dust is screened out and mainly transported to the rotary kiln or the feeding hopper through a closed conveyor for re-treatment. However, due to reasons such as low moisture content, small particle size and poor wettability of the dust, when it falls into the conveyor, dust will be raised, polluting the environment; when the dust is directly transferred into the feeding hopper, it will affect the feeding rate of the quantitative belt scale and the volume of the quantitative feeding amount, resulting in an increase in the volume of the feeding amount in the rotary kiln, causing the overall system to lose pressure and emit dust; at the same time, after the dust entering the kiln passes through the cyclone dust collector again, it is screened out again, continuously accumulating and circulating, reducing the treatment efficiency of the overall system. Therefore, applying a dust treatment device to spray and stir the dust under high pressure atomization, then pre-press and feed it through a screw to roll and granulate it into a spherical shape, and then transport it to the feeding hopper through a closed conveyor for re-treatment can not only reduce dust, improve the treatment efficiency and reduce energy consumption, but also make the overall system operate more stably.

[0003] The dust treated by the existing cyclone dust removal system is mainly transported to the rotary kiln or the feeding hopper through a closed conveyor for re-treatment. The dust in the feeding hopper will affect the feeding rate of the quantitative belt scale and the volume of the quantitative feeding amount, resulting in an increase in the volume of the feeding amount in the rotary kiln, causing the overall system to lose pressure and emit dust. At the same time, under a certain negative pressure, after the dust entering the kiln passes through the cyclone dust removal system again, it is screened out again, continuously accumulating and circulating, reducing the treatment efficiency of the overall system. Summary of the Utility Model

[0004] In order to improve the problem in the related technology that the dust after cyclone dust removal is directly transported to the rotary kiln or the feeding hopper, causing dust pollution to the environment and destroying the stability of the overall system. At the same time, the dust accumulates and circulates continuously in the system, reducing the soil treatment efficiency. The present application provides a dust treatment device for a direct thermal desorption system, which reduces environmental pollution, improves production efficiency and ensures the stability of the direct thermal desorption overall system by changing the state of the dust and the way of entering the kiln body.

[0005] The utility model provides a dust treatment device for a direct thermal desorption system, which comprises a cyclone dust collector (, a cylinder body, a cone body, an air inlet, an air outlet, a dust collection chamber, an infrared induction start switch, an infrared induction stop switch, an automatic ash discharging valve, a high-pressure atomizing spray chamber, a double-shaft dust stirrer, a double-shaft dust stirrer variable-frequency motor, a screw feeder, a screw feeder variable-frequency motor, a pair-roller extrusion granulator, a pair-roller extrusion granulator variable-frequency motor, an enclosed conveyor, a temperature thermocouple, a pressure transmitter and an automatic control system. After the tail gas in the rotary kiln passes through the cyclone dust collection, large-particle dust stays in the lower dust collection chamber below. When the dust in the dust collection chamber reaches a certain amount, it will trigger the infrared induction start switch, causing the whole set of equipment to operate automatically. The dust in the dust collection chamber flows into the high-pressure atomizing spray chamber through the automatic ash discharging valve, enters the double-shaft dust stirrer after being humidified, and the stirred dust enters the screw feeder, is pre-pressed by the screw and fed to the pair-roller extrusion granulator to form spherical dust, and then is transported to the feed hopper through the enclosed conveyor for re-treatment. When the dust is reduced to a certain amount, it triggers the infrared induction stop switch and the equipment stops running. On the one hand, after the dust is humidified, stirred and extruded into granules, it can reduce the environmental pollution caused by the dust. On the other hand, the dust does not need to be directly returned to the kiln, thus improving the overall stability of the system.

[0006] As a further technical solution of the utility model, the cyclone dust collector is arranged between the rotary kiln and the secondary combustion chamber and is used for dust removal treatment of the tail gas in the rotary kiln, and mainly consists of parts such as a cylinder body, a cone body, an air inlet, an air outlet, a dust collection chamber and an automatic ash discharging valve.

[0007] Furthermore, a temperature thermocouple is installed at the air inlet of the cyclone dust collector, and a pressure transmitter is installed at the air outlet.

[0008] Furthermore, an infrared induction start switch is arranged at the top of the dust collection chamber below the cyclone dust collector, and an infrared induction stop switch is arranged at the bottom.

[0009] Furthermore, a high-pressure atomizing spray chamber is installed at the bottom of the automatic ash discharging valve, and the spray makes the moisture content of the dust 10% - 15%.

[0010] Furthermore, in order to make the dust and the spray water stir evenly and have sufficient fusion time, the double-shaft dust stirrer adopts double-shaft co-rotation and is driven by a double-shaft dust stirrer variable-frequency motor.

[0011] Furthermore, in order to make the screw feeder cooperate well with the pair-roller extrusion granulator, it is driven by a screw feeder variable-frequency motor.

[0012] Furthermore, the pressure of the pair-roller extrusion granulator is adjusted by the pressure of the hydraulic cylinder, so as to achieve precise control of the material.

[0013] By changing the dust state and the way of entering the kiln body, the environmental pollution can be reduced, the production efficiency can be improved, and the stability of the direct thermal desorption system can be ensured.

[0014] This equipment has a high degree of automatic control, is relatively simple to operate, has a high processing efficiency, good overall stability, is safe and reliable, has a low failure rate, and reduces costs. Brief Description of the Drawings

[0015] Figure 1 It is a schematic structural diagram of the present utility model.

[0016] In the figure, 1. Cyclone dust collector, 2. Cylinder body, 3. Cone, 4. Air inlet, 5. Air outlet, 6. Dust collection chamber, 7. Infrared induction start switch, 8. Infrared induction stop switch, 9. Automatic ash discharge valve, 10. High-pressure atomizing spray chamber, 11. Double-shaft dust stirrer, 12. Double-shaft dust stirrer variable-frequency motor, 13. Screw feeder, 14. Screw feeder variable-frequency motor, 15. Roller extrusion granulator, 16. Roller extrusion granulator variable-frequency motor, 17. Enclosed conveyor, 18. Temperature thermocouple, 19. Pressure transmitter. Detailed Description of the Preferred Embodiment

[0017] The following will further elaborate on this application in conjunction with the attached Figure 1 drawings.

[0018] Please refer to Figure 1 , the present utility model provides a dust treatment device for a direct thermal desorption system, which includes a cyclone dust collector 1, a cylinder body 2, a cone 3, an air inlet 4, an air outlet 5, a dust collection chamber 6, an infrared induction start switch 7, an infrared induction stop switch 8, an automatic ash discharge valve 9, a high-pressure atomizing spray chamber 10, a double-shaft dust stirrer 11, a double-shaft dust stirrer variable-frequency motor 12, a screw feeder 13, a screw feeder variable-frequency motor 14, a roller extrusion granulator 15, a roller extrusion granulator variable-frequency motor 16, an enclosed conveyor 17, a temperature thermocouple 18, a pressure transmitter 19 and an automatic control system.

[0019] Please refer to Figure 1 , the present utility model provides a dust treatment device for a direct thermal desorption system. Its technological process is that the tail gas in the rotary kiln passes through cyclone dust removal, and the large-particle dust stays in the lower dust collection chamber 6. When the dust in the dust collection chamber 6 reaches a certain amount, it will trigger the infrared induction start switch 7, making the whole set of equipment run automatically. The dust in the dust collection chamber 6 flows into the high-pressure atomizing spray chamber 10 through the automatic ash discharge valve 9, enters the double-shaft dust stirrer 11 after humidification, and the stirred dust enters the screw feeder 13, is pre-pressed by the screw and fed to the roller extrusion granulator 15 to form spherical dust, and then is transported to the feed hopper through the enclosed conveyor 17 for re-treatment. When the dust is reduced to a certain amount, it triggers the infrared induction stop switch 8, and the equipment stops running.

[0020] Please refer to Figure 1 , the cyclone dust collector 1 is installed between the rotary kiln and the secondary combustion chamber, and is used for dust removal of the tail gas in the rotary kiln. It mainly consists of a cylinder body 2, a cone 3, an air inlet 4, an air outlet 5, a dust collection chamber 6, an automatic ash discharge valve 9 and other parts. After the tail gas enters the cylinder body 2, it rotates under the action of centrifugal force, and large particle dust falls into the bottom dust collection chamber, and fine dust is discharged from the air outlet.

[0021] Please refer to Figure 1 , the temperature thermocouple 18 is installed at the air inlet 4 of the cyclone dust collector 1 and is used to monitor the temperature of the flue gas.

[0022] Please refer to Figure 1 , the pressure transmitter 19 is installed at the air outlet 5 of the cyclone dust collector 1 and is used to monitor the pressure of the system and judge the dust removal effect.

[0023] Please refer to Figure 1 , an infrared induction start switch 7 is set at the top of the dust collection chamber 6, and an infrared induction stop switch 8 is set at the bottom. When the dust in the dust collection chamber 6 is full, the infrared induction switch 7 is turned on and the equipment starts; when the dust decreases to the bottom, the infrared induction switch 8 is turned off and the equipment stops.

[0024] Please refer to Figure 1 , the high-pressure atomizing spray chamber 10 sends water to the nozzle through a high-pressure pump to form a water mist, and the water mist reacts with the dust particles, so that the dust is wetted and settled.

[0025] Please refer to Figure 1 , the double-shaft dust stirrer 11 is used to continuously stir and mix the atomized dust under the action of the spiral stirring blades to make wet ash with a moisture content of 10% - 15% and continuously push it to the discharge port.

[0026] Please refer to Figure 1 , the screw feeder 13 is used to supply the stirred dust to the roll extrusion granulator 15. It mainly drives the screw blade to rotate through the motor, and the feeding material is carried downward by the rotating screw blade, so that the material is degassed and pre-pressed by the screw for feeding the roll extrusion granulator 15.

[0027] Please refer to Figure 1 , the roll extrusion granulator 15 is used to extrude the dust into a shape. Mainly, the material is subjected to a great extrusion force between two rotating rollers, resulting in plastic deformation of the material and being pressed into a spherical shape. The magnitude of the extrusion force is adjusted by the pressure of the hydraulic cylinder, so as to achieve precise control of the material.

[0028] Please refer to Figure 1, the enclosed conveyor 17 is used to convey the dust balls formed by the pair-roller extrusion granulator 15 to the feed hopper through the enclosed conveyor 17 for reprocessing.

[0029] The electrical control system of this equipment includes temperature thermocouples, pressure transmitters, infrared induction switches, frequency conversion motors, hydraulic cylinders, cables, cable trays, PLCs, and control cabinets.

[0030] This equipment has a high degree of automation control, is relatively simple to operate, has a high processing efficiency, good overall stability, is safe and reliable, has a low failure rate, and reduces costs.

[0031] The above describes the basic principles, main features, and advantages of the present invention. The present invention is not limited by the above specific embodiments, and the above specific implementation and the description in the specification are only to further illustrate the principle of the present invention. Without departing from the spirit scope of the present invention, the present invention will have various changes and improvements, and these changes and improvements all fall within the scope of the present invention claimed. The scope of protection claimed by the present invention is defined by the claims and their equivalents.

Claims

1. A direct thermal desorption system dust treatment equipment, characterized in that: The rotary kiln comprises a cyclone dust collector (1), a cylinder (2), a cone (3), an air inlet (4), an air outlet (5), a dust collecting chamber (6), an infrared sensor start switch (7), an infrared sensor shut-off switch (8), an automatic ash discharge valve (9), a high-pressure atomizing spray chamber (10), a double-shaft dust mixer (11), a double-shaft dust mixer frequency conversion motor (12), a screw feeder (13), a screw feeder frequency conversion motor (14), a double-roll extrusion granulator (15), a double-roll extrusion granulator frequency conversion motor (16), a closed conveyor (17), a temperature thermocouple (18), a pressure transmitter (19) and an automatic control system. The tail gas in the rotary kiln passes through the cyclone After dust removal, large dust particles remain in the dust collecting chamber (6) below. When the dust in the dust collecting chamber (6) reaches a predetermined amount, an infrared sensing start switch (7) is triggered to automatically operate the entire equipment. The dust in the dust collecting chamber (6) flows into the high-pressure atomizing spray chamber (10) through the automatic dust discharge valve (9), and enters the double-axis dust mixer (11) after humidification. The stirred dust enters the screw feeder (13), and is fed to the roller extrusion granulator (15) through the screw pre-pressing, so that the dust is formed into a ball shape, and then transported to the feed hopper through the closed conveyor (17) and re-processed. When the dust is reduced to a predetermined amount, the infrared sensing close switch (8) is triggered, and the equipment stops running.

2. The direct thermal desorption system dust treatment equipment according to claim 1, characterized in that: The cyclone dust collector (1) is installed between the rotary kiln and the secondary combustion chamber and is used for dust removal of tail gas in the rotary kiln. The cyclone dust collector (1) mainly comprises a cylinder (2), a cone (3), an air inlet (4), an air outlet (5), a dust collecting chamber (6) and an automatic ash discharge valve (9).

3. The direct thermal desorption system dust treatment equipment according to claim 1, characterized in that: A temperature thermocouple (18) is installed at the air inlet (4) of the cyclone dust collector (1), and a pressure transmitter (19) is installed at the air outlet (5).

4. The direct thermal desorption system dust treatment equipment according to claim 1, characterized in that: An infrared induction start switch (7) is arranged at the top of the dust collecting chamber (6) below the cyclone dust collector (1), and an infrared induction close switch (8) is arranged at the bottom.

5. The direct thermal desorption system dust treatment equipment according to claim 1, characterized in that: A high-pressure atomizing spray chamber (10) is installed at the bottom of the automatic ash discharge valve (9).

6. The direct thermal desorption system dust treatment equipment according to claim 1, characterized in that: The double-shaft dust agitator (11) is driven by a double-shaft co-rotating and double-shaft dust agitator variable frequency motor (12).

7. The direct thermal desorption system dust treatment equipment according to claim 1, characterized in that: The screw feeder (13) is driven by a screw feeder variable frequency motor (14).

8. The direct thermal desorption system dust treatment equipment according to claim 1, characterized in that: The pressure of the roller extrusion granulator (15) is adjusted by the pressure of the hydraulic cylinder.

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