CN112264447A - Thermal desorption device for soil restoration - Google Patents

Abstract

The invention discloses a thermal desorption device for soil remediation, and belongs to the technical field of soil remediation. The technical scheme of the invention is as follows: the cooling liquid in the cooling box is heated and then evaporated and enters the cooling tank, so that the evaporated cooling liquid gas forms a heat protection layer in the cooling tank, the heat exchange efficiency between the inside and the outside of the heat release box is reduced, the continuous high-temperature state in the heat release box is further maintained, the heat of the high-temperature gas is fully utilized, the heat loss is reduced, meanwhile, the temperature in the heat release box is always kept in a stable state, the efficient heat release treatment state can be maintained, and the overall heat release efficiency is improved; secondly, the evaporating liquid of the cooling liquid gradually dissipates the heat of the cooling liquid to the outside and then condenses, and the condensed cooling liquid flows back to the cooling box again, so that the circulating condensation effect is realized.

Description

Thermal desorption device for soil restoration

Technical Field

The invention belongs to the technical field of soil remediation, and particularly relates to a thermal desorption device for soil remediation.

Background

Along with the increasing of organic pollution of soil, the remediation of organic pollution solid waste is one of the key means for the organic pollution recovery of soil; the existing technology for repairing organic pollution solid waste comprises the following steps: biological repair process, chemical leaching process, gas phase extraction technology and thermal desorption method;

the thermal desorption technology is a technology for desorbing volatile substances from the volatile substances by direct or indirect heating, and is one of effective technologies for repairing polluted soil; different from incineration, the thermal desorption technology does not decompose organic pollution components, but heats the organic pollution components in the soil to volatilize by direct or indirect heating, so that the organic pollution components are separated from the soil, and the aim of restoring the soil is fulfilled; the heat of the existing thermal desorption technology cannot be fully utilized in the actual operation process, and most of the heat is rapidly exchanged with the outside in the desorption process so as to dissipate, so that the heat utilization rate is low, a large amount of heat is needed for treating a small amount of soil, the energy consumption required by treatment is large, and the thermal desorption technology is not suitable for repairing and treating a large amount of soil.

Disclosure of Invention

The technical problems to be solved by the invention are as follows: the thermal desorption device for soil restoration is energy-saving and efficient, and aims to solve the problems that the thermal desorption heat utilization rate of soil is low and the heat dissipation is fast in the prior art.

In order to solve the technical problems, the invention adopts the following technical scheme:

a thermal desorption device for soil restoration comprises a cylindrical thermal desorption box, wherein a plurality of groups of supports for supporting the thermal desorption box are symmetrically fixed on the lower side of the circumferential outer wall of the thermal desorption box, a group of discharge holes are formed in the side wall of the thermal desorption box in a penetrating manner, a feed pipe is inserted into the circumferential side wall of the thermal desorption box far away from one end of the discharge holes in a penetrating manner, a fixed cylinder is welded on the inner wall of the thermal desorption box near one end of the discharge holes, an air inlet pipe communicated with the inside of the fixed cylinder is inserted into the circumferential side wall of the thermal desorption box in a penetrating manner, the circumferential side wall of the fixed cylinder is provided with a plurality of vent holes in a penetrating manner, one end of the fixed cylinder far away from the discharge holes is rotatably connected with a rotating shaft, a group of driving rotating blades are welded on the circumferential side wall of the rotating shaft, the rotating shaft is connected with a hollow auger rotating rod rotatably connected, the circumference outer wall of auger bull stick is equipped with the auger blade, the one end outer wall that the discharge opening was kept away from to the hot knockout drum is equipped with the cooling device who is used for gas condensation to collect.

In foretell energy-conserving high-efficient type soil restoration uses thermal desorption system, reflux unit is including seting up a plurality of backward flow holes on the auger bull stick inner wall, cooling device is including fixing the cooler bin of keeping away from on the one end outer wall of discharge opening at the thermal desorption case, the one end outer wall that the discharge opening was kept away from to the thermal desorption case sets up the cooling bath with the cooler bin intercommunication, the inner wall of cooling bath is fixed with the diaphragm.

In the above-mentioned thermal desorption system for energy-saving high-efficient type soil restoration, the diaphragm is waterproof ventilated membrane, the inner wall of discharge opening is fixed with the board that refines that is used for breaing up soil.

In foretell energy-conserving high-efficient type soil remediation is with thermal desorption system, reflux unit includes a plurality of breather pipes that run through sliding connection with the auger bull stick lateral wall, every the breather pipe is located the inside one end welding of auger bull stick and has the pterygoid lamina, every the breather pipe is located the outside one end welding of auger bull stick and has the scraper blade, every the lateral wall of breather pipe all runs through and has seted up a plurality of inlet ports and venthole, the inside that the venthole corresponds the inlet port and is close to the auger bull stick is compared to the venthole.

Compared with other methods, the method has the beneficial technical effects that:

according to the invention, the introduced high-speed high-temperature airflow drives the driving rotating blade to rotate, so that the driving rotating blade drives the auger rotating rod to rotate, soil can be pushed by the pushing action of auger blades on the surface of the auger rotating rod, a continuous thermal desorption process is formed, the soil does not need to be manually replaced, extra driving force does not need to be provided, and the whole process is more convenient, efficient and energy-saving; pollutants evaporated by heating enter the auger rotating rod through the backflow hole, so that the separation of soil and the pollutants is realized, the pollutants are taken out through high-speed airflow, and pollutant gas carried by high-temperature airflow is condensed under the cooling effect of cooling liquid in the cooling box, so that the separation of the pollutants and the high-temperature airflow is realized, the collection of the pollutants is facilitated, and secondary pollution is avoided; the cooling liquid in the cooling box is evaporated and enters the cooling tank after being heated, so that the evaporated gas of the cooling liquid forms a heat protective layer in the cooling tank, the heat exchange efficiency between the inside and the outside of the heat release box is greatly reduced, the continuous high-temperature state in the heat release box can be kept, the heat of the high-temperature gas is fully utilized, the heat loss is avoided, the energy-saving work is realized, meanwhile, the temperature in the heat release box is always kept in a stable state, the efficient heat release treatment state can be kept, and the overall heat release efficiency can be improved; secondly, evaporating liquid of the cooling liquid gradually dissipates heat of the cooling liquid to the outside in the cooling groove and then condenses the cooling liquid into a liquid state, the cooling liquid cannot contact the inner side wall of the cooling groove again under the action of the diaphragm, so that the heat in the heat release box cannot be absorbed, the dissipation speed of the heat in the heat release box is reduced, and the condensed cooling liquid flows back to the cooling box again to realize a circulating condensation effect; according to the invention, when high-temperature airflow flows through the wing plate, air pressure difference occurs on two sides of the wing plate, so that the wing plate on the lower side pushes the scraper on the lower side to be inserted into soil, the scraper pushes the soil to move along with the rotation of the auger rotating rod, the soil on the lower side moves to the upper side, and when the scraper moves to the upper side, the scraper moves downwards under the action of gravity, so that the soil on the scraper is scattered on the upper side of the auger rotating rod, the differentiation and uniform distribution of the soil are realized, the contact area of the soil and the auger rotating rod is increased, and the overall heat removal efficiency is improved.

Drawings

FIG. 1 is a schematic structural diagram of a first embodiment of an apparatus according to the present invention;

FIG. 2 is a cross-sectional view taken along the line A-A in FIG. 1;

FIG. 3 is a schematic structural diagram of another embodiment of the present invention;

FIG. 4 is a cross-sectional view taken along the line B-B in FIG. 3;

1. thermally stripping the box; 2. a support; 3. a discharge hole; 4. a feed pipe; 5. a fixed cylinder; 6. a vent hole; 7. a rotating shaft; 8. driving the rotating blade; 9. a screw conveyor rotating rod; 10. a return orifice; 11. a cooling tank; 12. a cooling tank; 13. a diaphragm; 14. an air inlet pipe; 15. thinning the plate; 16. a screw blade; 17. a breather pipe; 18. a squeegee; 19. a wing plate; 20. an air inlet; 21. and an air outlet.

Detailed Description

The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings in the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention. The words "upper", "lower", "left" and "right" when used herein are merely intended to designate corresponding upper, lower, left and right directions in the drawings, and do not limit the structure thereof.

Example 1

The thermal desorption device for soil restoration comprises a cylindrical thermal desorption box 1, a plurality of groups of supports 2 for supporting the thermal desorption box 1 are symmetrically fixed on the lower side of the circumferential outer wall of the thermal desorption box 1, a group of discharge holes 3 are formed in the side wall of the thermal desorption box 1 in a penetrating manner, a feeding pipe 4 is inserted in the circumferential side wall of one end of the thermal desorption box 1, which is far away from the discharge holes 3, a fixed cylinder 5 is welded on the inner wall of one end of the thermal desorption box 1, which is close to the discharge holes 3, an air inlet pipe 14 communicated with the inside of the fixed cylinder 5 is inserted in the circumferential side wall of the thermal desorption box 1 in a penetrating manner, a plurality of air vents 6 are formed in the circumferential side wall of the fixed cylinder 5, one end of the fixed cylinder 5, which is far away from the discharge holes 3, is rotatably connected with a rotating shaft 7, a group of driving rotating blades 8 are welded on the circumferential side wall of the rotating shaft 7, the rotating blades 8 are driven by high-, the reduction gears is ordinary planetary gear reduction gears, vent 6 is located the inside of auger bull stick 9 and auger bull stick 9 is sealed rotation with solid fixed cylinder 5 and is connected, avoid high temperature gas stream to leak, gu fixed cylinder 5 passes through vent 6 intercommunication with auger bull stick 9, the circumference inner wall of auger bull stick 9 is equipped with the reflux unit who is used for the gaseous pollutants to collect, the circumference outer wall of auger bull stick 9 is equipped with auger blade 16, the one end outer wall that discharge opening 3 was kept away from to heat-stripping case 1 is equipped with the cooling device who is used for the gas condensation to collect.

The reflux device comprises a plurality of reflux holes 10 arranged on the inner wall of the auger rotating rod 9, the cooling device comprises a cooling box 11 fixed on the outer wall of one end of the thermal desorption box 1 far away from the discharge hole 3, and a cooling groove 12 communicated with the cooling box 11 is arranged on the outer wall of one end of the thermal desorption box 1 far away from the discharge hole 3; the cooling box 11 is filled with cooling liquid for absorbing heat, the cooling groove 12 is arc-shaped with five sixths, surrounds the heat release box 1 and avoids the position of the feeding pipe 4, so that the phenomenon that the heat is transferred to untreated soil by evaporated cooling liquid gas to cause that the heat is radiated too fast and a protective layer cannot be formed is avoided, and meanwhile, the phenomenon that the soil which does not completely enter the heat release box 1 is heated to cause that pollutants volatilize to outside air to cause secondary pollution is avoided; the packing auger rotating rod 9 is formed by rotationally connecting a propelling part positioned in the thermal stripping box 1 and a cooling part attached to the side wall of the cooling box 11, and the propelling part of the packing auger rotating rod 9 is in penetrating rotational connection with the side wall of the thermal stripping box 1.

The inner wall of the cooling tank 12 is fixed with a diaphragm 13, the diaphragm 13 is a waterproof breathable film and can only allow gas to pass through, liquid is isolated by the diaphragm 13, the cooling liquid enters the cooling tank 12 after being gasified to form a heat protection layer, so that the heat exchange efficiency between the inside of the thermal desorption tank 1 and the external environment is reduced, the heat exchange is just carried by the gasified cooling liquid instead of the heat exchange, the evaporating liquid of the cooling liquid close to the outside is firstly condensed, the condensed cooling liquid is attached to the outer side wall of the cooling tank 12, the cooling liquid at the upper end drops on the diaphragm 13 under the action of gravity, so that the cooling liquid cannot contact the inner side wall of the cooling tank 12 again, the heat inside the thermal desorption tank 1 is not absorbed, the heat dissipation speed inside the thermal desorption tank 1 is reduced, the condensed cooling liquid slides along the diaphragm 13 and finally flows into the cooling tank 11, the heat of the pollutants is absorbed again to form a circulating cooling treatment effect;

the inner wall of discharge opening 3 is fixed with refines board 15 that is used for breaing up soil, it is latticed to refine board 15, can be at the soil of the in-process dispersion caking that outwards shifts out of soil, refine the processing with soil, convenient subsequent direct use or at processing, and owing to refine board 15 and refine the separation process and have certain resistance, make soil pass and refine board 15 when basically seal discharge opening 3, can avoid the gaseous outflow of the inside evaporation's of thermal desorption case 1 pollutant, make pollutant can only enter into auger bull stick 9 inside and then discharged through backward flow hole 10, avoid forming secondary pollution.

When the thermal desorption remediation is carried out on soil, untreated soil is poured into the thermal desorption box 1 through the feeding pipe 4, then high-temperature steam is injected into the thermal desorption box 1 through the air inlet pipe 14, high-temperature air flow enters the fixed cylinder 5 through the air inlet pipe 14 and enters the auger rotating rod 9 through the vent hole 6, the air flow flows towards the cooling box 11 and contacts the driving rotating blade 8 in the flowing process, so that the driving rotating blade 8 is forced to rotate under the high-speed impact of the air flow, the auger rotating rod 9 is driven to rotate, the auger blade 16 is arranged on the outer wall of the auger rotating rod 9, the rotation of the auger rotating rod 9 can convey the untreated soil in the thermal desorption box 1 to one end of the discharge hole 3 from one end of the feeding pipe 4, and continuous thermal desorption treatment is formed;

in the flowing process of high-temperature air flow, heat is continuously transferred to the auger rotating rod 9 and indirectly transferred to untreated soil, so that pollutants such as organic matters in the soil are heated and evaporated and then are separated from the soil, because the air flow velocity in the auger rotating rod 9 is high and the pressure intensity is small, and because the accumulated pressure intensity of polluted gas is large outside the auger rotating rod 9, air pressure difference exists between two sides, gaseous pollutants enter the auger rotating rod 9 through the backflow hole 10 under the action of air pressure and move to one end of the cooling box 11 under the drive of the high-temperature air flow, so that the pollutants are completely separated from the soil, the soil is continuously treated in the moving process, the pollutants are completely desorbed when the soil is finally discharged through the discharge hole 3, and the soil can be finely treated under the action of the latticed refining plate 15 to prevent caking, influence on subsequent use;

the polluted gas flowing along with the high-temperature airflow passes through the cooling box 11 and is recovered to be liquid under the condensation action of the cooling liquid in the cooling box 11, so that the separation from the high-temperature gas is realized, the collection and the treatment of pollutants are convenient, the cooling liquid in the cooling box 11 can generate a certain degree of evaporation gas after absorbing heat, the evaporated cooling liquid flows into the cooling tank 12 and gradually fills the cooling tank 12 to form a heat protection layer, the efficiency of heat exchange between the inside and the outside of the heat release box 1 is greatly reduced, the continuous high-temperature state in the heat release box 1 can be further maintained, the heat of the high-temperature gas is fully utilized, the heat loss is avoided, the energy-saving purpose is realized, meanwhile, the temperature in the heat release box 1 is always kept in a stable state, the efficient heat release treatment state can be maintained, and the overall heat release efficiency can be improved, the cooling liquid gas evaporated into gaseous state gradually dissipates its heat to the outside in the cooling tank 12 and then condenses into liquid state, and then flows back to the cooling tank 11 again, thereby realizing the circulating condensation effect.

Example 2

The difference from the embodiment 1 is that the reflux device comprises a plurality of vent pipes 17 which are in penetrating sliding connection with the side wall of the packing auger rotating rod 9, one end of each vent pipe 17, which is positioned inside the packing auger rotating rod 9, is welded with a wing plate 19, one end of each vent pipe 17, which is positioned outside the packing auger rotating rod 9, is welded with a scraper 18, the side wall of each vent pipe 17 is provided with a plurality of air inlets 20 and air outlets 21 in a penetrating way, and the air outlets 21 are closer to the inside of the packing auger rotating rod 9 than the corresponding air inlets 20; the inner side of the wing plate 19 is a plane, and the other side of the wing plate 19 is a curved surface, so that when air flows through the wing plate 19, air pressure difference occurs on two sides of the wing plate 19 due to flow speed difference, and the wing plate 19 can push the scraper 18 on the lower side to be inserted into soil.

When high-temperature steam flows in the auger rotating rod 9, the high-temperature steam passes through the surface of the wing plate 19, so that the wing plate 19 moves under the action of air pressure difference, the scraper 18 at the lower end moves downwards under the action of gravity and air pressure and is inserted into soil, the scraper 18 at the upper end moves downwards under the action of gravity to overcome the action of air pressure, the scraper 18 at the lower end pushes the soil to move to the upper end along with the rotation of the auger rotating rod 9, and moves downwards under the influence of gravity when reaching the uppermost end, so that the soil is scattered on the surface of the auger rotating rod 9, the stirring of the soil is realized, the contact area between the soil and the auger rotating rod 9 is increased, the overall heating efficiency is improved, in order to ensure that the soil can be scattered after the soil at the lower side is pushed to the upper side by the scraper 18, the soil conveying capacity in the heat release box 1 is maintained in the discharging and conveying process of the soil, and the soil, so that enough scattering space is reserved inside the heat stripping box 1 and on the upper side of the auger rotating rod 9.

When the breather pipe 17 is located the upside of auger bull stick 9, breather pipe 17 is inside to auger bull stick 9 to remove under the action of gravity for venthole 21 and inlet port 20 are located auger bull stick 9 inside and outside both sides respectively, realize that auger bull stick 9 is inside to take off the inside intercommunication of case 1 with heat, make the gaseous pollutants after the evaporation can enter into auger bull stick 9 inside to realize with the separation and subsequent the collection of soil.

The present invention has been further described with reference to specific embodiments, but it should be understood that the detailed description should not be construed as limiting the spirit and scope of the present invention, and various modifications made to the above-described embodiments by those of ordinary skill in the art after reading this specification are within the scope of the present invention.

Claims (4)

1. The thermal desorption device for soil restoration comprises a cylindrical thermal desorption box (1) and is characterized in that a plurality of groups of supports (2) used for supporting the thermal desorption box (1) are symmetrically fixed on the lower side of the circumferential outer wall of the thermal desorption box (1), a group of discharge holes (3) are formed in the side wall of the thermal desorption box (1) in a penetrating mode, a feeding pipe (4) is formed in the circumferential side wall of the thermal desorption box (1) far away from one end of the discharge holes (3) in a penetrating mode, a fixed cylinder (5) is welded on the inner wall of the thermal desorption box (1) close to one end of the discharge holes (3), an air inlet pipe (14) communicated with the inside of the fixed cylinder (5) is formed in the circumferential side wall of the thermal desorption box (1) in a penetrating mode, a plurality of air vents (6) are formed in the circumferential side wall of the fixed cylinder (5), and a rotating shaft (7) is connected to one end of, the welding of the circumference lateral wall of pivot (7) has a set of drive commentaries on classics leaf (8), pivot (7) are connected with through reduction gears and rotate hollow auger bull stick (9) of being connected with solid fixed cylinder (5), the circumference inner wall of auger bull stick (9) is equipped with the reflux unit who is used for gaseous pollutants to collect, the circumference outer wall of auger bull stick (9) is equipped with auger blade (16), the one end outer wall that discharge opening (3) were kept away from in hot knockout box (1) is equipped with the cooling device who is used for the gas condensation to collect.

2. The thermal desorption device for soil remediation according to claim 1, wherein the reflux device comprises a plurality of reflux holes (10) formed in the inner wall of the auger rotating rod (9), the cooling device comprises a cooling box (11) fixed on the outer wall of one end, away from the discharge hole (3), of the thermal desorption box (1), the outer wall of one end, away from the discharge hole (3), of the thermal desorption box (1) is provided with a cooling tank (12) communicated with the cooling tank (11), and a diaphragm (13) is fixed on the inner wall of the cooling tank (12).

3. The thermal desorption device for soil remediation according to claim 2, wherein the diaphragm (13) is a waterproof and breathable membrane, and a refining plate (15) for scattering soil is fixed on the inner wall of the discharge hole (3).

4. The thermal desorption device for soil remediation of claim 1, wherein the reflux unit includes a plurality of breather pipes (17) that run through sliding connection with the side wall of the auger rotating rod (9), each breather pipe (17) is welded with wing plates (19) at the end inside the auger rotating rod (9), each breather pipe (17) is welded with scraper blades (18) at the end outside the auger rotating rod (9), each side wall of the breather pipe (17) is run through and is opened with a plurality of air inlets (20) and air outlets (21), the air outlets (21) are closer to the inside of the auger rotating rod (9) than corresponding air inlets (20).

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