WO2020168875A1

WO2020168875A1 - Rotary indirect thermal desorption device and system

Info

Publication number: WO2020168875A1
Application number: PCT/CN2020/072524
Authority: WO
Inventors: 郭超; 韩增平; 林慧丽; 梁仁刚; 郝燕超; 娄希民; 林纪晓; 张树立
Original assignee: 杰瑞环保科技有限公司
Priority date: 2019-02-22
Filing date: 2020-01-16
Publication date: 2020-08-27
Also published as: CN109692869A

Abstract

A rotary indirect thermal desorption device and a system comprising a rotary indirect thermal desorption device. Said device comprises a kiln head (1), a kiln end (2), a rotary cylinder body (3), a combustion chamber (4), a feed port (7), a discharge port (8) and a chimney (5); the kiln head, the rotary cylinder body, and the kiln end are connected in sequence, the combustion chamber is sleeved on the rotary cylinder body, the chimney is provided on the combustion chamber, the feed port is provided on the kiln head, the discharge port is provided on the kiln end, the kiln head is further provided with an exhaust port (9), and a plurality of burners (10) are provided on the bottom of the combustion chamber. The rotary cylinder body is partitioned according to the attribute change of materials along the path; furthermore, several shovelling plates (20) on an inner wall of the rotary cylinder body also have different welding angles with the inner wall of the rotary cylinder body according to different partitions. The rotary indirect thermal desorption device and the system comprising a rotary indirect thermal desorption device have a high heating temperature and a good thermal desorption effect, and achieve energy recovery and utilization by using heat released from the combustion of a non-condensable gas.

Description

Rotary indirect thermal desorption device and system

Technical field

The invention relates to the field of soil restoration, in particular to a rotary indirect thermal desorption device and system.

Background technique

Due to the burning of fossil fuels, oil spills, industrial sewage and sludge agricultural, industrial and agricultural solid waste stacking, and the widespread use of pesticides, many types of organic pollutants enter the soil environment directly or indirectly, and are absorbed by soil particles and remain in the soil for a long time in. Organic matter polluting the soil is divided into natural organic matter and synthetic organic matter, usually the latter, such as phthalates, polycyclic aromatic hydrocarbons, organochlorines, organophosphorus pesticides, etc. Many of these organic matter are carcinogenic, teratogenic or cause Mutant substances remaining in the soil will not only reduce crop yields or even eliminate crops, but also enter the food chain through animals and plants, which will have a serious impact on human survival and health. Therefore, the development of organic contaminated soil remediation technology has become a hot spot in environmental protection research at home and abroad. .

The traditional screw-propelled indirect thermal desorption equipment has small processing capacity, low heating temperature, and unsatisfactory repair effect. Therefore, it is urgent to develop a device to achieve efficient remediation of organic contaminated soil.

Summary of the invention

The purpose of the present invention is to overcome the shortcomings of the prior art and provide a rotary indirect thermal desorption device and system, which is suitable for materials with low liquid content and high looseness, large processing capacity, high heating temperature and repair effect Good, to achieve efficient restoration of organic contaminated soil and meet the demand for energy reuse.

The purpose of the present invention is achieved through the following technical measures: a rotary thermal desorption device, including a kiln head, a kiln tail, a rotary cylinder, a combustion chamber, a feed port, a discharge port, a chimney, the kiln head, The rotary cylinder and the kiln tail are connected in sequence, the combustion chamber is sleeved on the rotary cylinder, the chimney is provided on the combustion chamber, the feed port is provided on the kiln head, and the discharge port is provided on the kiln end , The kiln head is also provided with an exhaust port, the bottom of the combustion chamber is provided with a plurality of burners, the rotary cylinder is partitioned according to the changes in the properties of the material along the way, and a number of copying on the inner wall of the rotary cylinder According to the different partitions of the plate, the welding angle of the copy plate and the inner wall of the rotary cylinder is also different.

Further, the straight line connecting the kiln head, the rotary cylinder, and the kiln tail forms an angle with the horizontal plane, the angle is 1 to 3°, and the inlet is higher than the outlet.

Further, the rotary cylinder is divided into a heating section, an evaporation section and a dry material section in order from the kiln head to the kiln tail direction according to the property changes along the material.

Further, the copy board is a metal bent board with a height of 20-30 cm, and a V-shaped notch is opened in the middle of the upper end of the copy board.

Further, in the temperature rising section and the dry material section, the angle of the tangent line in the direction of rotation between the root of the plate and the inner wall of the rotary cylinder is 120°-150°.

Further, in the evaporation section, the angle between the root of the sheet and the tangent line in the rotation direction of the inner wall of the rotary cylinder is 60°-90°.

Further, the front end of the combustion chamber is provided with a partition in the axial direction for extending the flue gas stroke.

A rotary thermal desorption system, including a rotary thermal desorption device, a hopper, an air lock, a discharge jacket screw, a ceramic filter, a tubular condenser, an oil-water separator, a buffer tank, a buffer tank, and mist removal The device, the high-pressure fan, the flame arrester, the burner, the hopper, and the air lock are connected in sequence and then connected to the inlet of the rotary thermal desorption device, and the exhaust port of the rotary thermal desorption device is connected to the ceramic filter in sequence , Tube-and-tube condenser, demister, high-pressure fan, flame arrestor, burner connection, the burner is set at the bottom of the front end of the combustion chamber of the rotary thermal desorption device, and the inlet of the oil-water separator is connected to the tube-type The condenser is connected, the outlet of the oil-water separator is respectively connected with a buffer oil tank and a buffer water tank, and the discharge port of the rotary thermal desorption device is screwed with a discharge jacket.

Further, the defogging device is a three-stage defogging device, which is a one-stage defogger, a two-stage defogger, and a three-stage defogging device. The first-stage defogging device is provided with several baffles, so Several corrugated plates are arranged in the two-stage mist eliminator, and a fiber layer is arranged in the three-stage mist eliminator.

Compared with the prior art, the present invention has the following beneficial effects: 1. The multiple burners are arranged evenly horizontally, and the heating temperature and uniformity are guaranteed; 2. The section-designed copy board realizes the effective turning and turning of the contaminated soil. The rapid diffusion and release of pollutant vapor; 3, three-stage defogging to ensure the stability and environmental protection of non-condensable gas combustion; the configuration of 4 burners can fully burn non-condensable gas and release heat to realize energy recovery and utilization.

The present invention will be described in detail below in conjunction with the drawings and specific embodiments.

Description of the drawings

Figure 1 is a schematic structural diagram of a rotary thermal desorption device.

Figure 2 is a schematic diagram of the structure of the copy board.

Figure 3 is a schematic diagram of the welding angle of the plate in the heating section and the dry material section.

Figure 4 is a schematic diagram of the welding angle of the plate in the evaporation section

Figure 5 is a schematic diagram of the distribution of the copy board on the inner wall of the rotating cylinder.

Figure 6 is a schematic structural diagram of a rotary thermal desorption system.

Figure 7 is a schematic diagram of the structure of the burner.

Among them, 1. Kiln head, 2. Kiln tail, 3. Rotary cylinder, 4. Combustion chamber, 5. Chimney, 6. Partition, 7. Feed port, 8. Discharge port, 9. Exhaust port, 10. Burner, 20. Copy plate, 21. Root, 22. Notch, 30. Burner, 31. Non-condensing gas channel, 32. Air channel, 41. Hopper, 42. Air lock, 43. Discharge jacket Spiral, 44. Ceramic filter, 45. Tubular condenser, 46. Oil-water separator, 47. Cache fuel tank, 48. Cache water tank, 49. Primary demister, 50. Secondary demister, 51. Three-stage mist eliminator, 52. High pressure fan, 53. Flame arrestor.

detailed description

As shown in Figure 1, a rotary thermal desorption device includes a kiln head 1, a kiln tail 2, a rotary cylinder 3, and a fixed combustion chamber 4. The kiln head 1 is provided with a feed port 7 and an exhaust port 9. The kiln tail 2 is provided with a discharge port 8, the bottom of the combustion chamber 4 is provided with multiple burners 10, and the chimney 5 is provided at the top of the front end of the combustion chamber 4. A plurality of burners 10 arranged evenly horizontally provide high-temperature flue gas and heat. The organic contaminated soil enters the kiln head 1 and the rotary cylinder 3 through the inlet 7 and is connected by the kiln head 1, the rotary cylinder 3, and the kiln end 2. The formed straight line forms an angle with the horizontal plane. The angle is 1 to 3°. The inlet 7 is higher than the outlet 8, ensuring that the soil in the cylinder has a certain axial flow rate when the rotary cylinder 3 rotates around the central axis. Indirect thermal desorption is achieved during the process of turning and flowing, and finally discharged from the discharge port 8. The front section of the combustion chamber 4 is provided with a partition 6 in the axial direction for extending the flue gas stroke. The flue gas channel is cut off to prevent the flue gas of the front burner 10 from being directly discharged upward from the chimney 5 to form a short circuit and affect the heat exchange efficiency.

The inner wall of the rotary cylinder 3 is welded with a plurality of copy plates 20, the copy plates 20 are metal bent plates, the height is 20-30cm, the upper end of the copy plate 20 is provided with a V-shaped notch 22, and the root 21 of the copy plate 20 It is welded to the inner wall of the rotating cylinder 3, and the specific structure of the plate 20 is shown in FIG. 2. And according to the material properties changes along the way, the partition design is carried out. The specific plan is as follows: for the heating and thermal desorption process of the material in the rotating cylinder 3, the rotating cylinder 3 is divided into a heating section, an evaporation section and a dry material section in the axial direction. : The material in the heating section is heated from the ambient temperature to the superheated steam temperature of about 130°C. The vaporization amount is small and the heat absorption intensity is relatively large at this stage; a large amount of water evaporates in the evaporation section, and some organic pollutants evaporate, and this stage vaporizes The material in the dry material section continues to heat up to the final processing temperature (400～500℃), the remaining organic pollutants in this stage are all evaporated, the gasification amount is the smallest, and the heat absorption intensity Minimal, the overall heating rate is accelerated. Therefore, in view of the characteristics of the heating section, the tangential included angle between the root 21 and the wall of the rotary cylinder 3 is an obtuse angle, usually 120°～150°, as shown in Figure 3; The tangential included angle of the cylinder wall of the rotating cylinder 3 is an acute angle, usually 60°～90°, as shown in Fig. 4; in the dry material section and the heating section, the welding angle of the plate 20 is the same. Welding angles are calculated in a clockwise direction. The number of copy plates 20 in each section of the heating section, the evaporation section and the dry material section is six, and the six copy plates 20 are evenly distributed in the circumferential direction of the inner wall of the rotating cylinder 3, as shown in FIG. 5. The copy board 20 in the heating section is beneficial to increase the paving area of the material and ensure a certain degree of turning; the copy board 20 in the evaporation section is beneficial to increase the degree of material turning and form a "material curtain", which promotes the rapid escape of steam inside the particle layer; On the one hand, the board 20 in the dry material section can promote the diffusion of a small amount of organic pollutant vapor remaining in the material, and on the other hand, it can avoid excessive dust.

A rotary thermal desorption system, including a rotary thermal desorption device, a hopper 41, an air lock 42, a discharge jacket screw 43, a ceramic filter 44, a tubular condenser 45, an oil-water separator 46, and a buffer tank 47. Buffer water tank 48, primary demister 49, secondary demister 50, tertiary demister 51, high-pressure fan 52, flame arrestor 53, etc., as shown in FIG. 6. The specific implementation is as follows: the organic contaminated soil enters the rotary indirect thermal desorption device through the air lock 42 from the hopper 41, and the soil that has completed the thermal desorption process falls into the discharge jacket spiral 43, the discharge jacket spiral 43 The outer jacket is filled with cooling water to cool the high-temperature soil; after the pollutant vapor released by the thermal desorption process of organic polluted soil is discharged from the rotary indirect thermal desorption device, it first passes through the ceramic filter 44, There are several ceramic fiber tubes inside, which can effectively filter out the dust particles in the pollutant vapor; after that, the pollutant vapor enters the tubular condenser 45, and cooling water is passed into the shell side of the tubular condenser 45. The pollutant vapor is indirectly condensed to convert the pollutant vapor into condensate and non-condensable gas; the condensate flows into the oil-water separator 46 for precipitation and separation of moisture and oil, the upper slick oil is connected to the buffer tank 47, and the bottom water is connected Enter the buffer water tank 48; the initially obtained non-condensable gas contains a lot of water mist and oil mist, and is filtered and removed by the first-stage mist eliminator 49, the second-stage mist eliminator 50, and the third-stage mist eliminator 51 in sequence. There are several baffles in the demister 49, several corrugated plates in the secondary demister 50, and a fiber layer in the three-stage demister 51. The three-stage demister ensures the stability and combustion of non-condensable gas. Environmental protection; the non-condensable gas after the three-stage defogging is passed through the high-pressure fan 52 and then passed through the flame arrestor 53, and finally connected to the non-condensable gas burner 30 arranged on the rotary indirect thermal desorption device for full combustion and heat release. Energy recycling. The non-condensable gas burner 30 is a single sleeve type burner structure, and includes a non-condensable gas channel 31 and an air channel 32, as shown in FIG. 7. The non-condensable gas burner 30 also needs to be equipped with an ignition device, a combustion-supporting fan, a control module, etc., so as to fully utilize the non-condensable gas energy.

Claims

A rotary thermal desorption device includes a kiln head, a kiln tail, a rotary cylinder, a combustion chamber, a material inlet, a material outlet, a chimney, the kiln head, the rotary cylinder, and the kiln tail are connected in sequence, and the combustion The cavity is sleeved on the rotary cylinder, the chimney is set on the combustion chamber, the feed port is set on the kiln head, and the discharge port is set on the kiln tail. The feature is that the kiln head is also provided There is an exhaust port, the bottom of the combustion chamber is provided with multiple burners, the revolving cylinder is partitioned according to the changes in the properties of the material along the way, and several copy plates on the inner wall of the revolving cylinder are different according to the partitions. The welding angle of the inner wall of the rotating cylinder is also different.
The rotary thermal desorption device according to claim 1, characterized in that: the straight line connecting the kiln head, the rotary cylinder and the kiln tail forms an angle with the horizontal plane, the angle is 1-3°, and the feed port Higher than the discharge port.
The rotary thermal desorption device according to claim 1, wherein the rotary cylinder is divided into a heating section, an evaporation section and a dry material section in order from the kiln head to the kiln end according to the properties of the material along the way. .
The rotary thermal desorption device according to claim 3, characterized in that: the copy board is a metal bent board with a height of 20-30 cm, and a V-shaped notch is opened in the middle of the upper end of the copy board.
The rotary thermal desorption device according to claim 4, characterized in that: in the heating section and the dry material section, the angle between the root of the sheet and the tangent line in the direction of rotation of the inner wall of the rotary cylinder is 120°～150 °.
The rotary thermal desorption device according to claim 4, wherein in the evaporation section, the angle of the tangent line in the direction of rotation between the root of the sheet and the inner wall of the rotary cylinder is 60°-90°.
The rotary thermal desorption device according to claim 1, wherein the front end of the combustion chamber is provided with a partition for extending the flue gas stroke in the axial direction.
A rotary thermal desorption system, characterized in that it comprises the rotary thermal desorption device according to any one of claims 1-7, a hopper, an air lock, a discharge jacket screw, a ceramic filter, and a tube type The condenser, the oil-water separator, the buffer oil tank, the buffer water tank, the demister, the high-pressure fan, the flame arrestor, the burner, the hopper, and the air lock are connected in sequence and then connected to the inlet of the rotary thermal desorption device. The exhaust port of the rotary thermal desorption device is connected to the ceramic filter, the tubular condenser, the demister, the high-pressure fan, the flame arrester, and the burner in sequence, and the burner is set in the combustion of the rotary thermal desorption device At the bottom of the front end of the cavity, the inlet of the oil-water separator is connected with the tubular condenser, the outlet of the oil-water separator is respectively connected with the buffer oil tank and the buffer water tank, and the discharge port and the discharge port of the rotary thermal desorption device Jacketed screw connection.
The rotary thermal desorption device according to claim 8, wherein the defogging device is a three-stage defogging device, which is a first-stage defogger, a second-stage defogger, and a third-stage defogger. A number of baffles are arranged in the first-stage mist eliminator, a number of corrugated plates are arranged in the second-stage mist eliminator, and a fiber layer is arranged in the third-stage mist eliminator.