KR20200094331A - Thermal desorption apparatus of using microwave - Google Patents

Abstract

The present invention discloses a thermal desorption treatment apparatus using microwaves that irradiates a heating element located around contaminated soil and thermally desorbs contaminated soil using radiant heat generated from the heating element. According to the present invention, the thermal desorption treatment apparatus using microwaves comprises: a transfer unit for thermal desorption treatment while transferring contaminated soil; the heating element providing heat for thermal desorption treatment of contaminated soil to the transfer unit; and an oscillation unit for generating microwaves and irradiating the heating element.

Description

Thermal desorption apparatus of using microwave

The present invention is an invention for an apparatus for thermally desorption of contaminated soil by heating a heating element using microwaves. Specifically, microwaves are used as an energy transmission means, but instead of irradiating the microwaves directly to contaminated soils, the surroundings are contaminated. Regarding a device for thermally desorbing contaminated soil using radiant heat generated from the heating element by irradiating the heating element located at the heat generating element, a microwave that allows such a process to be performed in the middle of moving the contaminated soil to a destination through a transfer unit using a screw The present invention relates to a thermal desorption treatment apparatus.

The interest in preventing environmental pollution was mainly focused on water and air purification, and the soil has received relatively little attention because it does not show any effect within a short period of time even if it is contaminated, unlike air or water. Problems such as oil pollution by underground oil storage facilities such as regions have been recently discussed.

In general, oil spills, which are mainly caused by underground oil storage facilities, petrochemical plant-related industries, and other illegal landfills of oil, pollute the soil, which is the basis of survival for all terrestrial ecosystems, including humans. Soil pollution is defined as a condition that damages a person's health or the environment for reasons such as waste from human activities being thrown on the surface of the soil or underground. It does not appear, but once contaminated, the soil itself cannot be used, and the pollution spreads to the groundwater and nearby rivers, which adversely affects the ecosystem.

The technology for purifying such oil contaminated soils can be largely divided into biological methods and physicochemical methods. The physicochemical methods have shortcomings, but have a high cost of treatment and can cause secondary environmental pollution. The biological method is a method of decomposing and removing oil by using microorganisms, which are petroleum hydrocarbon-decomposing strains, and has a disadvantage that it takes a long time to restore contaminated soil.

The prior art has been heating the contaminated soil using microwaves as a heating means to overcome this disadvantage. However, the prior art, as disclosed in Patent Publication No. 10-2009-0117278, used a method of heating the soil in a manner that directly irradiates microwaves to the soil. There was a disadvantage in that it was difficult to penetrate into the soil, and it was difficult to heat the deep part of the contaminated soil. In order to heat the inside of the contaminated soil to a desired temperature, there was a disadvantage in that microwaves of a stronger intensity were generated by using more power.

Patent Publication No. 10-2009-0117278 (released on December 12, 2009)

The problem to be solved by the present invention is to use the microwave as an energy transmission means to solve the problems of the prior art as described above, but not a method of directly irradiating polluted soil, heating the heating element around the polluted soil and radiant heat generated therefrom It is an object to provide a heat desorption treatment apparatus using microwaves to vaporize contaminants in contaminated soil using.

In addition, the object to be solved by the present invention is to provide a thermal desorption treatment apparatus using a microwave capable of thermal desorption treatment while moving a contaminated soil to a destination using a screw while stirring.

In order to achieve the object of the present invention as described above, the present invention, in the heat desorption processing apparatus, the transfer unit for heat desorption while transporting the contaminated soil, the heating element and the microwave to provide heat for heat desorption of the contaminated soil to the transfer unit It provides a heat desorption processing apparatus using a microwave characterized in that it comprises an oscillation unit to generate and irradiate with the heating element.

The transfer part is provided with a casing for receiving contaminated soil, a paddle screw provided inside the casing to move the contaminated soil in one direction by a rotational motion, an axis of rotation of the paddle screw to rotate a paddle screw, and a rotation axis for rotating the paddle screw. It is preferable to include a motor part to rotate.

The casing includes a starting end in the vicinity of where the contaminated soil begins to be transported, and an end portion in the vicinity of the transfer destination of the contaminated soil, and a first outlet for discharging gas generated from the contaminated soil to the outside is provided at the upper end of the casing, It is preferable that a second discharge port for discharging the contaminated soil moved to the end of the casing to the outside is provided at the bottom of the end.

The casing is preferably cylindrical.

It is preferable that the oscillation portion includes a magnetron.

It is preferable to further include an input portion through which contaminated soil is introduced from the outside of the thermal desorption treatment device to the transfer portion.

The input unit is an inlet hopper for introducing contaminated soil into the input unit, a transfer device for transporting the contaminated soil introduced into the input unit, a drying device for drying the contaminated soil transported by the transfer device, and the drying device. It is preferable to include a crushing device for crushing the dried contaminated soil and an inlet for introducing the crushed contaminated soil into the transfer unit.

The crushing device is preferably a stabilizer method is applied.

The heating element is preferably formed in a shape surrounding the casing.

The heating element includes a main heating element provided along the lower outer circumferential surface of the casing and a secondary heating element provided along the upper outer circumferential surface of the casing, and the main heating element is preferably provided in a thicker form than the secondary heating element.

It is preferable that the primary heating element includes a plurality of primary heating element blocks, and the secondary heating element includes a plurality of secondary heating element blocks.

Preferably, the heat desorption treatment apparatus further includes an intake portion that absorbs vaporized contaminants from the first outlet.

Preferably, the intake unit includes a blower that provides a suction force so that the vaporized contaminants in the casing are easily sucked, and a cooling device that cools the inhaled vaporized contaminants.

It is preferable that the transfer part is provided with a material capable of blocking microwaves and includes a blocking part formed to surround the casing and the heating element.

It is preferable that the oscillation portion is provided inside the blocking portion.

Preferably, the oscillation portion is provided outside the blocking portion, and the blocking portion includes a through hole capable of receiving the microwave generated by the oscillation portion inside the blocking portion at a position adjacent to the microwave irradiation position of the oscillation portion.

It is preferable to include a temperature sensor that detects temperature information of the heating element inside the casing and a control unit that receives temperature information of the heating element from the temperature sensor and controls the temperature inside the casing to maintain a constant range.

Further comprising a power supply for supplying power to the oscillation unit, it is preferable that the control unit controls the power supply unit to control the temperature inside the casing.

Preferably, the control unit includes an operation switch capable of turning on/off power supplied from the power supply unit to the oscillation unit.

In the embodiment of the present invention configured as described above, since radiant heat is transmitted to a depth inside the soil, it is possible to heat the entire contaminated soil, thereby enabling more efficient heat desorption treatment.

In addition, in the embodiment of the present invention configured as described above, since the contaminated soil moves through the conveying unit and receives heat from the heating element, thermal desorption treatment is possible for the contaminated soil, thereby reducing the time required for the heat desorption treatment process.

1 is a view showing a heat desorption processing apparatus using microwaves to describe the first embodiment of the present invention.
2 is a view showing a heat desorption processing apparatus using microwaves to describe a second embodiment of the present invention.
3 is a view showing in detail the input part of the heat desorption processing apparatus using the microwave of the second embodiment of the present invention.
4 is a view showing a heat desorption processing apparatus using microwaves to describe a third embodiment of the present invention.
5 is a view showing a heat desorption processing apparatus using microwaves to describe a fourth embodiment of the present invention.
6 is a view showing a cross-section of a thermal desorption processing apparatus using microwaves according to a fifth embodiment of the present invention.
7 is a view showing a cross-section of a thermal desorption processing apparatus using microwaves according to a sixth embodiment of the present invention.
8 is a diagram for a material and a state of the heating element as an experimental example of the present invention.
FIG. 9 is a diagram showing a change in temperature of contaminated soil according to an SIC heating element and a block type heating element as an experimental example of the present invention.
FIG. 10 is a diagram showing a change in temperature of a heating unit when the number of microwave oscillation units (irradiation units) is different as an experimental example of the present invention.
11 is a view showing an arrangement of heat observation sensors on the upper and side surfaces of the heating element after the heating element is covered with contaminated soil as an experimental example of the present invention.
12 is a diagram showing the temperature change of the upper soil and the side soil when the heating element is heated as an experimental example of the present invention.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art to which the present invention pertains may easily practice. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. However, these embodiments are provided to make the disclosure of the present invention complete, and to fully disclose the scope of the invention to those skilled in the art. The same reference numerals will be used for the same names throughout the specification. In addition, the terminology used herein is for describing the embodiments, and is not intended to limit the present invention. In the present specification, the singular form also includes the plural form in some cases unless otherwise specified in the phrase. As used herein, “comprises” and/or “comprising” does not exclude the presence or addition of one or more other components other than the components mentioned. Unless otherwise defined, all terms used in this specification may be used in a sense that can be commonly understood by those skilled in the art to which the present invention pertains. In addition, terms defined in the commonly used dictionary are not ideally or excessively interpreted unless explicitly defined. Other advantages and features of the present invention, and a method of achieving them will become apparent by referring to embodiments described below in detail together with the accompanying drawings.

The thermal desorption treatment applied to the present invention includes applying a thermal desorption method to contaminated soil. In the thermal desorption method, the excavated contaminated soil in a contaminated area is introduced into a thermal desorption device to sufficiently raise the temperature of the soil so that the contaminants contained in the soil can volatilize, and change the contaminant in the soil to a gaseous state. It is a contaminated soil purification method that purifies by combustion and desorption. It is divided into high temperature heat desorption (400~800℃) and low temperature heat desorption (about 400℃ or less) by operating temperature to remove contaminants.

In the past, the low temperature heat desorption method (400°C or less) has been mainly used, but the high temperature heat desorption method (400 to 800°C) is required for efficient heat desorption treatment. However, as a means for applying high-temperature heat, a heating device using fossil fuel or a heating device using electricity may be used, but this is disadvantageous in that it is bulky, heavy, and difficult to transport, and has high installation and operation costs. Therefore, if a microwave generating device that is relatively easy to install, small in volume, and light in weight is used, the above disadvantages can be overcome.

1 is a view showing a heat desorption processing apparatus using microwaves to describe the first embodiment of the present invention.

According to Figure 1, the thermal desorption processing apparatus using a microwave according to the first embodiment of the present invention while transferring the contaminated soil (27), the transfer unit 20 for heat desorption processing, the contaminated soil (27) to the transfer unit 20 It is preferable to include a heating element 32 that provides heat for heat desorption treatment and an oscillation unit 31 that generates microwaves and irradiates the heating element 32.

The transfer unit 20 is provided inside the casing 24 and the casing 24 to accommodate the contaminated soil 27, the paddle screw 23 and the paddle screw 23 to move the contaminated soil 27 in one direction by rotational movement. It is preferable to include a rotating shaft 22 that rotates the paddle screw 23 by a stop rotation and becomes a shaft of rotation, and a motor unit 21 that rotates the rotating shaft 22.

At this time, the casing 24 accommodates the contaminated soil (27). It is preferable that the casing 24 extends in a substantially straight direction from the starting end portion A near the point where the contaminated soil 27 starts to be transferred to the end portion B near the destination for the transfer of the contaminated soil 27, and , The casing 24 is preferably provided in a cylindrical shape.

The contaminated soil 27 inside the casing 24 is moved to the end portion B by the rotational movement of the paddle screw 23, as described again below, by the heat supplied from the heating element 32 during the movement process Heat desorption treatment for the contaminated soil 27 may be performed. The casing 24 is an appropriate length for thermal desorption to be completed until the contaminated soil 27 is moved from the starting end (A) to the end (B) in consideration of the movement speed of the contaminated soil 27 and the heat desorption treatment speed. It can be provided as.

The motor part 21 is connected to the rotating shaft 22 and receives power from the outside to rotate the rotating shaft 22. At this time, the motor unit 21 is preferably provided outside the casing (24).

The rotation shaft 22 receives the rotational force from the motor unit 21 to rotate the paddle screw 23 and becomes the axis of rotation of the paddle screw 23. It is preferable that the rotation of the rotating shaft 22 is a stationary rotation with little movement of the position. The rotating shaft 22 is mostly located inside the casing 24 and a part of it protrudes out of the casing 24 and can be connected to the motor unit 21. It is preferable that the rotation shaft 22 extends in a direction substantially horizontal to the casing 24 from the motor part 21 and is provided at the center of the casing 24.

The paddle screw 23 is provided in a plurality of units inside the casing 24. The paddle screw 23 rotates with the rotating shaft 22 as an axis. The paddle screw 23 may be composed of one or a plurality of paddles.

The paddle (paddle) is preferably a sharp paddle with a sharp tip, and a broad ply shape on the upper side, which is thinner in thickness from the central axis toward the tip of the wing. The paddle screw 23 may include incoloy as a constituent material. By the rotational movement of the paddle screw 23, the contaminated soil 27 of the starting end portion A of the casing 24 moves toward the transfer destination in one direction, that is, near the end portion B of the casing 24.

The first discharge port 25 discharges gas generated from the contaminated soil 27 to the outside. The first outlet 25 is preferably provided at the top of the end portion (B) of the casing 24 so that the gas is naturally discharged to the outside.

The second discharge port 26 discharges the contaminated soil 27 moved to the end portion B of the casing 24 to the outside. The second outlet 26 is preferably provided at the bottom of the end portion B of the casing 24 so that the contaminated soil 27 is easily discharged to the outside, and may be provided in a tapered form.

The heating element 32 provides heat for thermal desorption treatment of the contaminated soil 27 by the transfer unit 20. The heating element 32 generates heat by receiving the energy of the microwave. The heating element 32 is located around the lower portion of the casing 24 to provide heat capable of thermally desorptioning the contaminated soil 27 inside the casing 24.

In addition, the heating element 32 may be composed of a by-product (Fe-Cr-Al-based) containing a large amount of iron components, or may include it as a component. In this case, the heating element 32 has high electrical resistance and can be more stabilized at a high temperature.

In addition, the by-product (Fe-Cr-Al-based) containing a large amount of a particle size of 5.0 mm or less and a quench steel slag particle having a sphericity of 0.5 or more or a particle size of 5.0 mm or less and a quench steel slag particle having a sphericity of 0.5 or more has a binder. It may be characterized in that it contains any one or more of the cured body cured by mixing. When the heating element 32 is formed using the quenched steel slag particles or a cured body thereof, the energy efficiency of the heating element 32 is higher than when the heating element 32 is formed using other materials.

The oscillation unit 31 generates microwaves so that the heating element 32 generates heat and irradiates it with the heating element 32. At this time, the oscillation unit 31 may include a magnetron, which is a device that generates microwaves by using the action of a magnetic field on moving electrons.

Figure 2 is a view showing a heat desorption processing apparatus using microwaves to describe the second embodiment of the present invention, Figure 3 is a second embodiment of the present invention showing a detailed input of the heat desorption processing apparatus using microwaves It is one drawing.

Other examples of the embodiments of the present invention will be described only different points compared to the above-described embodiment, and the same parts will be omitted by replacing the above description. In addition, functions of the above-described parts of other exemplary components of the embodiments of the present invention will be denoted by the same reference numerals as in the above-described examples.

According to FIG. 2, the heat desorption processing apparatus using microwaves according to the second embodiment of the present invention is an input for introducing the contaminated soil 27 from the outside of the apparatus to the starting end (A) of the casing 24 of the transfer unit 20 It may further include a portion (10).

According to FIG. 3, the input unit 10 transfers the polluted soil 27 introduced into the input unit 10 and the input hopper 15 that inputs the polluted soil 27 into the input unit 10. Transfer device 11, drying device 12 for drying the contaminated soil 27 transferred by the transfer device 11, crushing device 13 for crushing the contaminated soil 27 dried by the drying device 12 ) And crushed contaminated soil (27) it is preferable to include an inlet (16) for introducing into the transfer unit (20).

The input hopper 15 injects the contaminated soil 27 from the outside into the input unit 10. The contaminated soil 27 may be directly injected into the transport device 11 by the input hopper 15.

The transfer device 11 transfers the contaminated soil 27 input from the input hopper 15 to the input port 16. The conveying device 11 may be an automatic conveying device such as a conveyor belt.

The drying apparatus 12 dries the contaminated soil 27 moved by the transfer apparatus 11. The drying device 12 may be a device that irradiates heat.

The crushing device 13 crushes the soil dried by the drying device 12. The crushing device 13 can directly crush the contaminated soil 27 on the transport device 11. The crushing device 13 may be applied with a stabilizer method in which soil is crushed and mixed with soils having different particle sizes to improve particle size, and additives are mixed to be uniformly selected and chopped. The crushing device 13 may be made of Teflon or urethane.

The inlet 16 inputs the contaminated soil 27 dried and crushed by the above process to the transfer unit 20. The inlet 16 is preferably provided so that one surface close to the transport device 11 is inclined downward so that the contaminated soil 27 falling from the end of the transport device 11 can descend naturally.

In addition, the input unit 10 may further include a water discharge port 14 for discharging moisture and some vaporized contaminants generated during the process of crushing and drying the contaminated soil 27 to the outside.

4 is a view showing a heat desorption processing apparatus using microwaves to describe a third embodiment of the present invention.

Other examples of the embodiments of the present invention will be described only different points compared to the above-described embodiment, and the same parts will be omitted by replacing the above description. In addition, functions of the above-described parts of other exemplary components of the embodiments of the present invention will be denoted by the same reference numerals as in the above-described examples.

According to FIG. 4, the heating element 32 of the thermal desorption processing apparatus using microwaves of the third embodiment of the present invention may be formed in a form surrounding the casing 24.

In addition, the heating element 32 includes main heating elements 32 and 322 provided along the lower outer circumferential surface of the casing 24 and secondary heating elements 32 and 321 provided along the upper outer circumferential surface of the casing 24. The heating elements 32 and 322 are preferably provided in a thicker form than the auxiliary heating elements 32 and 321. Since the primary heating elements 32 and 322 are provided in a thicker form than the secondary heating elements 32 and 321, the primary heating elements 32 and 322 can generate heat at a higher temperature than the secondary heating elements 32 and 321.

In this way, by placing the main heating elements 32 and 322 at the lower portion of the casing 24 and the secondary heating elements 32 and 321 at the upper portion, the main heating elements 32 and 322 receive microwaves directly from the oscillating portion 31. There is an effect of dissipating heat energy, and the secondary heating elements 32 and 321 have an effect of improving energy efficiency for the heat desorption treatment process by reabsorbing microwaves passing out of the transfer unit 20 to release heat energy.

5 is a view showing a heat desorption processing apparatus using microwaves to describe a fourth embodiment of the present invention.

Other examples of the embodiments of the present invention will be described only different points compared to the above-described embodiment, and the same parts will be omitted by replacing the above description. In addition, functions of the above-described parts of other exemplary components of the embodiments of the present invention will be denoted by the same reference numerals as in the above-described examples.

According to FIG. 5, the thermal desorption processing apparatus using microwaves, which is a fourth embodiment of the present invention, provides suction power to the intake section 40 and the intake section 40 that absorb vaporized contaminants from the first outlet 25. It is preferable to further include a blower device 41, a cooling device 42 for cooling the sucked contaminants into a liquid or solid, and a blocking part 50 for blocking microwaves from escaping to the outside.

The intake unit 40 absorbs high-temperature contaminants (gas) generated inside the transfer unit 20. The intake unit 40 may include a blowing device 41 and a cooling device 42. The blower device 41 provides suction force to the intake unit 40 so that vaporized contaminants in the casing 24 are easily moved to the intake unit 40. The cooling device 42 cools the vaporized contaminants sucked into the intake unit 40. As a result of cooling, the contaminants change state from gas to liquid or solid, so the volume can be minimized to facilitate the disposal of the contaminants.

The blocking part 50 is preferably in the form of a blocking film surrounding the casing 24 and the heating element 32. That is, the blocking portion 50 is provided outside the casing 24 and the heating element 32.

The blocking portion 50 prevents microwaves from being emitted to the outside. The blocking portion 50 is made of a material capable of blocking microwaves. The blocking portion 50 is preferably formed of a metal material capable of blocking microwaves, particularly SUS (Steel Use Stainless).

At this time, the oscillation portion 31 may be included inside the blocking portion 50. The microwaves irradiated from the oscillation part 31 do not radiate outside the blocking part 50, but continue to stay inside the blocking part 50 and reach the heating element 32 through a process such as a straight line or reflection, thereby efficiently generating a heating element. (32) can be heated.

Meanwhile, the blocking portion 50 may be provided in a form in which the oscillation portion 31 is located outside the blocking portion 50. In this case, the blocking portion 50 may include a plurality of through holes 51. The through hole 51 is preferably provided adjacent to the microwave irradiation position of the oscillation portion 31. Accordingly, although the microwave is easily received from the oscillating portion 31 into the blocking portion 50 through the through hole 51, the microwave once accommodated into the blocking portion 50 cannot be diverted to the outside and is blocked inside the blocking portion 50 Since it is reflected from and reaches the heating element 32, the heating element 32 can be heated more efficiently.

6 is a view showing a cross-section of a thermal desorption processing apparatus using microwaves according to a fifth embodiment of the present invention.

Other examples of the embodiments of the present invention will be described only different points compared to the above-described embodiment, and the same parts will be omitted by replacing the above description. In addition, functions of the above-described parts of other exemplary components of the embodiments of the present invention will be denoted by the same reference numerals as in the above-described examples.

According to FIG. 6, the thermal desorption processing apparatus using a microwave according to a fifth embodiment of the present invention measures the temperature inside the casing 24 and transmits the temperature information to the control unit 34, temperature It includes a control unit 34 that receives temperature information from the sensor 33 and analyzes it to control the power supply unit 35, and a power supply unit 35 connected to the control unit 34 to supply power to the oscillation unit 31. desirable.

The control unit 34 receives temperature information inside the casing 24 from the temperature sensor 33. The control unit 34 may control the temperature inside the casing 24 to maintain a constant range. Specifically, the control unit 34 allows the oscillation unit 31 to operate when the temperature inside the casing 24 is lower than the lower limit temperature LT and stops the operation of the oscillation unit 31 when the upper limit temperature UT is reached. Can be controlled.

For example, it is as follows. When the temperature sensor 33 located inside the casing 24 detects a temperature lower than the lower limit temperature LT, power is supplied to the oscillation unit 31 so that the oscillation unit 31 generates microwaves. Then, the temperature of the heating element 32 rises, and as a result, the oscillation unit 31 continues to generate microwaves until the temperature around the heating element 32 reaches the upper limit temperature UT. At this time, the temperature sensor 33 transmits the temperature information of the heating element 32 to the control unit 34, and the control unit 34 automatically analyzes the temperature information.

The control unit 34 receiving the information that the temperature inside the casing 24 has reached the upper limit temperature UT cuts off the power supplied from the power supply unit 35 to the oscillation unit 31. Because the power is cut off, the oscillation unit 31 no longer generates microwaves, and accordingly, the temperature of the heating element 32 starts to drop. When the temperature inside the casing 24 continues to drop and the temperature around the heating element 32 reaches the lower limit temperature LT, the temperature sensor 33 transmits the information to the control unit 34. Upon receiving information that the temperature inside the casing 24 has reached the lower limit temperature LT, the control unit 34 controls the power supply to resume from the power supply unit 35 to the oscillation unit 31. In this case, the upper limit temperature (UT) is 750 to 850°C, the lower limit temperature (LT) is 350 to 450°C, more preferably, the upper limit temperature (UT) is 790 to 810°C, and the lower limit temperature (LT) is in the range of 340 to 410°C. Can be set in

In addition, the control unit 34 may include an operation switch sw capable of turning on/off the power supplied from the power supply unit 35 to the oscillation unit.

7 is a view showing a cross-section of a thermal desorption processing apparatus using microwaves according to a sixth embodiment of the present invention.

Other examples of the embodiments of the present invention will be described only different points compared to the above-described embodiment, and the same parts will be omitted by replacing the above description. In addition, functions of the above-described parts of other exemplary components of the embodiments of the present invention will be denoted by the same reference numerals as in the above-described examples.

The main heating element 322 according to the sixth embodiment of the present invention includes a plurality of main heating element blocks 323 provided along the lower outer circumferential surface of the casing 24. The primary heating element block 323 is preferably provided in a thicker form than the secondary heating element block 324 described below.

In addition, the secondary heating element 321 according to the sixth embodiment of the present invention includes a plurality of secondary heating element blocks 321 provided along the upper outer circumferential surface. The secondary heating element block 321 is preferably provided in a thinner form than the primary heating element block 323.

Compared to the fifth embodiment, in which the primary heating element 322 and the secondary heating element 321 are continuously formed as one unit, respectively, in the sixth embodiment, the primary heating element 322 and the secondary heating element 321 have a plurality of blocks. ) Is formed by being combined, it is possible to easily perform high-temperature treatment using a material of a smaller amount of the heating element, and in the working process of the heating element 32 adjacent to the outer peripheral surface of the casing 24 but formed along the outer peripheral surface It has the effect of reducing the cost.

Hereinafter, a specific experimental example related to the present invention will be described.

<Experimental Example 1>

FIG. 8 is a diagram of a material and a state of a heating element as an experimental example of the present invention, and FIG. 9 is a diagram showing a temperature change of contaminated soil according to an SIC heating element and a block type heating element as an experimental example of the present invention.

This experiment is an experiment to derive a heating element suitable for the thermal desorption method that removes contaminants from contaminated soil using heat generated from the heating element by irradiating microwaves to the heating element.

8(a) is a view showing a SIC (silicon carbide) heating element, which is a non-metallic heating element and is made of a honeycomb structure, which has a high thermal conductivity and is capable of being heated up to a maximum surface temperature of 1,600°C. In this case, the calorific value per unit area is 5 to 10 times higher than that of metal heating elements including nichrome wire.

FIG. 8(b) is a view showing a powdered iron compound heating element, which is a metal heating element and is characterized by being produced as a by-product (Fe-Cr-Al-based) containing a large amount of iron components generated in a steel mill. The heating element in this case has high electrical resistance and is stable at high temperatures. At this time, the by-product (Fe-Cr-Al-based) contained in a large amount is preferably a quenched steel slag particle having a particle size of 5.0 mm or less and a sphericity of 0.5 or more.

Figure 8 (c) is characterized in that the heating element processed in a block form by adding an adhesive material to the powdered iron compound heating element of Figure 8 (b). At this time, the powdered iron compound is preferably a cured product obtained by mixing a binder with quenched steel slag particles having a particle size of 5.0 mm or less and a sphericity of 0.5 or more and curing the particles.

9(a) and 9(b), when the SIC heating element and the block-type iron compound heating element are installed around the contaminated soil, but the same power is supplied to generate the heating element using a microwave oscillation unit (irradiation unit) of the same intensity. This graph shows the temperature change of the heating element.

Looking at the graph above, it can be seen that the peak temperature immediately after microwave irradiation of the SIC heating element and the block-type iron compound heating element is similar, but the width of the initial temperature drop of the SIC heating element is much larger than that of the iron compound heating element. However, since the width of the temperature drop of the block-type iron compound heating element is said to be relatively small, it is judged that better heating efficiency can be expected than the SIC heating element.

<Experimental Example 2>

Research time Heating element 32 position Upper part (℃) Lower part (℃) 5 minutes 132 166 10 minutes 179 275.8 15 minutes 225 338

[Table 1] is heated using two microwave oscillation units (irradiation units) having a capacity of 3 kW (total of 6 kw), and measures the temperature of the heating element at intervals of 5 minutes. The temperature of the heating element was measured by dividing the case where the microwave oscillation portion was at the top of the heating element and the case at the bottom of the heating element. As can be seen from the above data, it can be seen that the microwave oscillation unit has a higher heat transfer efficiency when located in the lower portion of the heating element.

<Experimental Example 3>

FIG. 10 is a diagram showing a change in temperature of a heating unit when the number of microwave oscillation units (irradiation units) is different as an experimental example of the present invention.

This experiment is to check the change in the temperature of the heating element for 50 minutes after irradiating the heating element with the microwave for 30 minutes by varying the number of microwave oscillation units (irradiation units) with a capacity of 3 kw.

The irradiation intensity of the microwave of the above experiment has an irradiation intensity of 3 kw when using one oscillation unit (irradiation unit) and 6 kw when using two oscillation units (irradiation unit).

According to FIG. 9, when two microwave oscillation units (irradiation units) were operated, the initial temperature was higher than 100° C., but the width of the initial temperature drop was larger than when one was operated.

On the contrary, when one microwave oscillation unit (irradiation unit) is operated, the initial temperature is lower than when two microwaves are operated, so it can be confirmed that the temperature continuously decreases without a relatively large falling period.

Accordingly, it was confirmed that even if the initial temperature drop width was large, increasing the number of microwave oscillations and increasing the irradiation intensity helped to increase the average temperature of the heating portion.

In addition, it was confirmed that after the microwave was irradiated for 30 minutes, the residual heat persisted in the heating portion for about 5 minutes.

<Experimental Example 4>

11 is an experimental example of the present invention, after covering the heating element with a contaminated soil, a view showing a heat observation sensor disposed on the upper and side surfaces of the heating element, and FIG. 12 is an experimental example of the present invention. It is a diagram showing the temperature change of soil and side soil.

In this experiment, the microwave oscillation unit (irradiation unit) is located on the top of the heating element, but the microwave oscillation unit and the heating element are installed to face each other in a straight line, then the heating element is covered with contaminated soil, and the heat sensor is placed on the top and side of the heating element to place the microwave. This is an experiment for observing the heat change pattern for each position when the oscillator is operated.

The heating element used in the above experiment is a block-type iron compound heating element, and two microwave oscillation units having a capacity of 3 kw are installed.

At this time, the microwave was irradiated to the heating element for 30 minutes for the first time and 30 minutes for the second time with a rest of 20 minutes.

According to FIG. 12, it was confirmed that, during the first irradiation, both the upper and side surfaces of the heating element gradually warmed up, and the temperature of the upper portion of the heating element that was directly radiated by the microwave was relatively higher.

In addition, it was confirmed that during the second irradiation, the polluted soil at the top of the heating part was heated up to 712.4°C in proportion to time, while the polluted soil at the side of the heating part showed a relatively low temperature change and maintained a low temperature of about 130°C. .

That is, even when the microwave oscillator is intermittently driven, such as the initial operation of the microwave oscillator, the supply of the microwave for a certain period of time, and then the microwave oscillator being operated intermittently, the temperature of the contaminated soil above the heating element is very high. It has been confirmed that the temperature can be increased up to, and it is confirmed that the energy can be relatively reduced.

<Experimental Example 5>

Through the experimental results identified in Experimental Examples 1 to 4, the contents and results of the heat desorption treatment apparatus using microwaves are as follows.

Experiment method Contents (1) Take a soil sample near the dioxin-contaminated site and confirm whether dioxin is detected before conducting the experiment. Soil sample 2.5kg (2) Soil sample dioxin detection confirmation result Toxicity equivalent: 1.1777 pg-TEG/g Actual concentration: 101.378 pg/g (3) Heat desorption treatment method using microwave Heating element: 1 block type heating element Irradiation type: Fixed
Irradiation intensity: 2 3kw oscillations (irradiation) (total 6kw)
Survey time: 1st survey (30 minutes)-Stop (20 minutes)-2nd survey (30 minutes)

unit Soil At the first investigation 2nd investigation ℃ 34.6 142.4 566.6 pg-TEG/g 1.1777 0.613 0.011 pg/g 101.378 35.333 4.060

According to [Table 2] and [Table 3], according to the results of this experiment, about 48% of the first irradiation (30 minutes) of microwave based on the concentration of raw soil of dioxin, and about 99 of the second irradiation (30 minutes) % Purification efficiency was confirmed.

For reference, in the case of the first irradiation (30 minutes) under the same conditions in the case of benzo(a) pyrene, a purification efficiency of about 93.4% appears, and in the case of dioxin, heat treatment is required for a relatively long time compared to benzo(a) pyrene. You can confirm that

Due to these characteristics, it is confirmed that when performing a process of thermal desorption of soil contaminated with dioxins, at least the first irradiation (30 minutes) is insufficient and at least the second irradiation 30 is further required.

10: input part 11: transfer device
12: drying device 13: crushing device
14: water outlet 15: input hopper
16: Inlet
20: transfer unit 21: motor unit
22: rotating shaft 23: paddle screw
24: casing 25: first outlet
26: second outlet 27: contaminated soil
31: oscillation unit 32: heating element
321: secondary heating element 322: primary heating element
323: primary heating element block 324: secondary heating element block
33: temperature sensor 34: control
35: power supply sw: switch
40: intake unit 41: blower
42: chiller
50: blocking portion 51: through

Claims (19)

In the thermal desorption processing apparatus,
A transfer unit for thermal desorption while transporting contaminated soil;
A heating element that provides heat for thermal desorption treatment of contaminated soil to the transfer unit; And
Includes; oscillation unit for generating a microwave to irradiate the heating element
Heat desorption treatment device using microwave. According to claim 1,
The transfer part
A casing that receives contaminated soil;
A paddle screw provided inside the casing to move the contaminated soil in one direction by a rotational movement;
A rotation axis that becomes an axis of rotation of the paddle screw and rotates the paddle screw; And
It includes; a motor unit for rotating the rotating shaft;
Heat desorption treatment device using microwave. According to claim 2,
The casing includes a starting end that is near the beginning of the transfer of the contaminated soil and a terminating end near the destination of the transport of the contaminated soil,
A first outlet for discharging gas generated from contaminated soil to the outside is provided at the upper end of the terminal,
At the lower end of the end portion, a second outlet for discharging the contaminated soil moved to the end portion of the casing is provided.
Heat desorption treatment device using microwave. According to claim 2,
The casing is characterized in that the cylindrical shape
Heat desorption treatment device using microwave. According to claim 1,
The oscillator comprises a magnetron, characterized in that
Microwave heating device. According to claim 1,
Further comprising an inlet to which contaminated soil is introduced from the outside of the heat desorption treatment device to the transfer unit
Heat desorption treatment device using microwave. The method of claim 6,
The input part
Inlet hopper for introducing contaminated soil into the input unit;
A transfer device for transporting the contaminated soil introduced into the input part;
A drying device for drying the soil contaminated by the transport device;
A crushing device for crushing contaminated soil dried by the drying device; And
Containing; an inlet for introducing the crushed soil to the transport unit
Heat desorption treatment device using microwave. The method of claim 7,
The crushing device is characterized in that the stabilizer method is applied
Heat desorption treatment device using microwave. According to claim 2,
The heating element is formed in a shape surrounding the casing
Heat desorption treatment device using microwave. The method of claim 9,
The heating element
A main heating element provided along a lower outer circumferential surface of the casing; And
Includes; secondary heating element provided along the upper outer peripheral surface of the casing,
The primary heating element is provided in a thicker form than the secondary heating element
Heat desorption treatment device using microwave. The method of claim 10,
The main heating element includes a plurality of main heating element blocks,
The secondary heating element includes a plurality of secondary heating element blocks
Heat desorption treatment device using microwave. According to claim 3,
The heat desorption treatment device
Further comprising an intake portion for absorbing vaporized contaminants from the first outlet
Heat desorption treatment device using microwave. The method of claim 12,
The intake section
A blowing device that provides suction force to facilitate suction of vaporized contaminants in the casing; And
Containing; cooling device for cooling the inhaled vaporized pollutants
Heat desorption treatment device using microwave. According to claim 2,
The transfer part
It is provided with a material capable of blocking microwaves, and includes a blocking portion formed to surround the casing and the heating element.
Heat desorption treatment device using microwave. The method of claim 14,
The oscillation unit
It is provided inside the blocking portion
Heat desorption treatment device using microwave. The method of claim 14,
The oscillation unit
It is provided on the outside of the blocking portion
The blocking portion
A hole adjacent to the microwave irradiation position of the oscillation unit including a through hole that can receive the microwave generated by the oscillation unit into the blocking unit
Heat desorption treatment device using microwave. According to claim 2,
A temperature sensor for sensing temperature information of the heating element inside the casing; And
And a control unit receiving temperature information of the heating element from the temperature sensor and controlling the temperature inside the casing to maintain a constant range.
Microwave heating device. The method of claim 17,
Further comprising a power supply for supplying power to the oscillation unit,
The control unit controls the power unit to control the temperature inside the casing
Heat desorption treatment device using microwave. The method of claim 18,
The control unit includes an operation switch capable of turning on/off the power supplied from the power supply unit to the oscillation unit.
Heat desorption treatment device using microwave.

Images