CN210305033U

CN210305033U - Soil thermal desorption clean system

Info

Publication number: CN210305033U
Application number: CN201920987998.7U
Authority: CN
Inventors: 嵇佳伟; 何健; 江建斌; 宋刚练; 殷俊; 顾春杰
Original assignee: Shanghai Geological Construction Co ltd
Current assignee: Shanghai Geological Construction Co ltd
Priority date: 2019-06-28
Filing date: 2019-06-28
Publication date: 2020-04-14
Anticipated expiration: 2029-06-28

Abstract

The utility model relates to a soil thermal desorption clean system, including letter sorting equipment, desicator, condenser, component ratio the control unit, combustor, pyrolysis equipment and the cooling arrangement that connect gradually, one side of condenser is equipped with the cooling tower, the pyrolysis device includes first heating furnace, second heating furnace and pyrolysis gas pipeline, it gets rid of unit and transfer fan to have arranged the foreign matter on the pyrolysis gas pipeline, the desicator is including shifting part and microwave production part, be equipped with rotatable heating chamber in the second heating furnace. The present system is suitable for purifying a large amount of contaminated soil BS composed of soil and sand, preferably using a microwave dryer, which has various advantages such as energy saving, production cost saving, high-speed drying, minimized labor force, minimized installation space, increased drying ratio due to volume heating, moisture content percentage uniformization and automation.

Description

Soil thermal desorption clean system

Technical Field

The utility model relates to a soil purification technology field especially relates to a soil thermal desorption clean system.

Background

When waste or contaminants are illegally dumped on the ground or buried under the ground, the soil is contaminated, and although the soil has a natural self-cleaning function, the natural cleaning of the soil requires a lengthy cleaning period, and the soil loses its natural self-cleaning ability in case of severe contamination, so that it cannot sufficiently cope with the present-day soil contamination. In the past, the process of artificially purifying contaminated soil using a thermal desorption system, which refers to a device for separating and eliminating contaminants contained in a contaminated medium, i.e., soil, by thermal desorption reaction. More specifically, thermal desorption systems apply direct heat to contaminated soil at elevated temperatures to burn the contaminants in the soil. However, since the conventional thermal desorption system directly heats the contaminated soil in the air to separate and oxidize the contaminants contained in the soil, there is a problem in that the combustion of the contaminants is hindered by moisture in the soil and water vapor in the air, thereby causing incomplete combustion of the contaminants contained in the soil. Further, since the incomplete combustion generates a large amount of exhaust gas containing various pollutants, and the exhaust gas contains environmental pollutants, which play a role in atmospheric pollution, there is a serious problem in that the atmospheric pollution becomes worse in spite of the use thereof.

SUMMERY OF THE UTILITY MODEL

In view of this, the utility model aims at providing a soil thermal desorption clean system to solve not enough among the prior art.

In order to achieve the above purpose, the purpose of the present invention is achieved by the following technical solutions:

the utility model provides a soil thermal desorption clean system, wherein, including letter sorting equipment, desicator, condenser, component ratio the control unit, combustor, pyrolysis equipment and the cooling arrangement who connects gradually, one side of condenser is equipped with the cooling tower, the pyrolysis device includes first heating furnace, second heating furnace and pyrolysis gas pipeline, foreign matter removal unit and conveying fan have been arranged on the pyrolysis gas pipeline, the desicator is including shifting part and microwave generation part, be equipped with rotatable heating chamber in the second heating furnace.

The soil thermal desorption purification system is characterized in that a dryness checking part and a bypass are arranged at the outlet of the dryer, one end of the bypass is connected to the transfer device leading to the pyrolysis device, and the other end of the bypass is connected to the transfer device leading to the starting point of the dryer.

The soil thermal desorption purification system, wherein the burner comprises an auxiliary fuel tank.

Compared with the prior art, the utility model has the advantages that:

the present system is suitable for purifying a large amount of contaminated soil BS composed of soil and sand, preferably using a microwave dryer, which has various advantages such as energy saving, production cost saving, high-speed drying, minimized labor force, minimized installation space, increased drying ratio due to volume heating, moisture content percentage uniformization and automation.

Drawings

The accompanying drawings, which form a part hereof, are included to provide a further understanding of the invention, and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the invention without undue limitation. In the drawings:

fig. 1 shows a schematic structural diagram of the present invention.

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 embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative efforts belong to the protection scope of the present invention.

It should be noted that, in the present invention, the embodiments and features of the embodiments may be combined with each other without conflict.

Referring to fig. 1, the utility model discloses soil thermal desorption clean system is including the letter sorting equipment 100 that connects gradually, the desicator 200, the condenser 300, component ratio the control unit 400, the combustor 500, pyrolysis equipment 600 and cooling arrangement 920, one side of condenser 300 is equipped with cooling tower 310, pyrolysis apparatus 600 includes first heating furnace 620, second heating furnace 630 and pyrolysis gas pipeline, foreign matter removal unit 700 and transfer fan 800 have been arranged on the pyrolysis gas pipeline, desicator 200 includes transfer part 210 and microwave generation part 220, be equipped with rotatable heating chamber 610 in the second heating furnace 630. The technical scheme also comprises a plurality of transfer devices for transferring and conveying materials. The temporary storage tank B is transferred to the sorting apparatus 100 by the transfer apparatus 101, such as a transfer conveyor, and then the contaminated soil in the temporary storage tank B is put into the sorting apparatus 100, wherein particles of the contaminated soil are classified by size or separated from heavy (light) metals. Referring to fig. 1, particles in contaminated soil are sorted by size using a sorting apparatus 100, and the contaminated soil is transferred to a dryer 200 by a plurality of

transfer apparatuses

102, 103, and 104 so that they can be manually sorted. The contaminated soil, which has been transferred from the sorting apparatus 100, passes through the dryer 200 while removing moisture contained in the contaminated soil. Moisture contained in the contaminated soil exists in the exhaust gas in the form of water vapor, preventing complete combustion of the exhaust gas in the burner 500, thereby lowering purification efficiency. Therefore, it is preferable that the moisture contained in the contaminated soil is completely separated, and when the contaminated soil passes through the dryer 200, the residual moisture in the contaminated soil is minimized and thus the moisture content of the pyrolysis gas generated at the pyrolysis apparatus 600 is minimized, so that the pyrolysis gas can be re-burned for recycling. As the dryer 200, various types may be applied according to the operation manner, and representative dryers may include a hot air dryer, a vacuum dryer, a microwave dryer, and the like. According to the embodiment of the polluted soil purification system, a microwave dryer is adopted. Since contaminated soil is composed of relatively fine soil particles, ventilation between the outside and the inside of the contaminated soil is insufficient, and a hot air dryer requiring ventilation of the subject to be dried is not suitable for drying the contaminated soil. The use of a microwave dryer has various advantages: saving, saving production cost, high-speed drying, minimizing labor force, minimizing installation space, increasing drying ratio due to volume heating, homogenizing and automating moisture content percentage. As shown, the dryer 200 includes a transferring part 210 and a microwave generating part 220, and may further include a dryness checking part 230 and a bypass 240, if necessary. The transferring part 210 serves to forcibly transfer the contaminated soil introduced into the dryer 200 while rotating in a spiral manner, and the microwave generating part 220 is provided in the drying chamber to dry the contaminated soil introduced into the drying chamber. For reference, the drying chamber may be provided with a conveyor that slowly moves the contaminated soil transferred from the transfer apparatus 210 while sufficiently exposing the contaminated soil to the microwaves generated from the microwave generating part 220. The contaminated soil, which releases a large amount of moisture while passing through the dryer 200, is transferred to the pyrolysis apparatus 600 by the transfer apparatus 202, and the exhaust gas generated from the contaminated soil is sent to the burner 500. The exhaust gas that has been diverted from the dryer 200 is used as fuel in the burner 500.

Of course, when used as fuel, the exhaust gas is completely burned and eliminated. Therefore, it is preferable to optimize the combustibility and combustion efficiency of the exhaust gas transferred to the combustor 500. Although the exhaust gas that has been diverted from the dryer 200 has a significantly reduced water content, it still contains a small amount of moisture.

This residual moisture hinders complete incineration in the burner 500, resulting in incomplete combustion. Subsequently, the offgas that has been transferred from the dryer 200 is conveyed to the condenser 300 along the mixed gas line ML, and the condenser 300 separates moisture from the offgas. The condenser 300 condenses the off-gas that has been supplied along the mixed gas line ML and then discharges the condensed water vapor, thus leaving only pure off-gas. The condenser 300, which is heated to a high temperature while it is operated, is cooled using cooling water, and necessary cooling water may be supplied from the cooling tower 310. For reference, the cooling tower 310 serves to receive water from the outside through a water supply line WL to cool the water, and to supply the cooling water to the condenser 300 through a cooling line CL connected to the condenser 300. The exhaust gas in the condenser 300 may obtain oxygen (air) required for combustion of the exhaust gas during transfer to the burner 500 through the waste line GL. The composition ratio control unit 400 is adapted to mix the exhaust gas delivered through the waste line GL with oxygen (air) delivered through the air supply line AL and generate conditions required for complete combustion in the burner 500. Generally, in order to achieve complete combustion of the exhaust gas, the exhaust gas and oxygen (air) must be mixed in a desired ratio. The composition ratio control unit 400 checks the composition ratio of the exhaust gas delivered through the exhaust gas line GL. As a result of the examination, when the oxygen (air) ratio does not satisfy the ideal ratio, the ratio of oxygen (air) and exhaust gas is controlled by adjusting the supply of oxygen (air). The exhaust gas whose composition ratio has been controlled is supplied to the burner 500 along the combustion gas line FL. Meanwhile, the contaminated soil, which has been dried and released moisture by the dryer 200, is transferred to the pyrolysis apparatus 600 by the transfer apparatus 202. At this time, when the contaminated soil is not sufficiently dried, a moisture content higher than a certain value may remain in the contaminated soil. The dryness of the contaminated soil is checked before transferring the dried contaminated soil to the pyrolysis apparatus 600. As a result of the examination, if the moisture content is found to be higher than a prescribed value, the contaminated soil is dried again. To this end, the dryer 200 is provided at an outlet thereof with a dryness checking part 230 and a bypass 240, and one end of the bypass 240 is connected to the transferring device 202 leading to the pyrolysis device 600, and a portion of the other end of the bypass 240 is connected to the transferring device 201 leading to a starting point of the dryer 200. More specifically, the dryness checking part 230 measures the moisture content of the contaminated soil discharged from the dryer 200, and determines whether the moisture content exceeds a specified value based on the measured value. Here, since a technique for measuring the moisture content is well known in the art, a detailed description of the dryness check portion 230 is omitted. As a result of the determination at the dryness checking part 230, when the moisture content of the dried contaminated soil BS is less than a prescribed value, the other end of the bypass 240 is closed and only one end of the bypass 240 is opened, and thus in order for the contaminated soil BS to be introduced into the pyrolysis apparatus 600. When the moisture content of the contaminated soil BS exceeds a prescribed value, one end of the bypass 240 is closed, and only the other end of the bypass 240 is opened, so as to allow the contaminated soil to be introduced into the transfer facility 201. The transfer device 201 may be connected directly to the dryer 200 or may be connected to a separate collection tank (not shown) so that further drying operations may be performed later. Finally, the contaminated soil having a moisture content higher than the prescribed value is subjected to the drying operation repeatedly two or more times until the moisture content is within the prescribed value. The dried contaminated soil is transferred to the pyrolysis apparatus 600 by the transfer apparatus 202, and the pyrolysis device 600 is heated by heating generated by complete combustion of the exhaust gas in the burner 500, thereby heating the contaminated soil. To this end, the pyrolysis apparatus 600 may include a heating chamber 610 hermetically maintaining contaminated soil, and first and

second heating furnaces

620 and 630 adapted to heat the heating chamber 610 using hot air passed therethrough. In a preferred embodiment, the heating chamber 610 is rotatably installed in the second heating furnace 630 so that contaminated soil is uniformly heated while being stirred. As a result, the contaminated soil is effectively divided into purified soil and pyrolysis gas. The resultant pyrolysis gas is again transferred to the burner 500 through the pyrolysis gas lines HL1, HL2, and HL3, and is mixed with the exhaust gas transferred through the combustion gas line FL and incinerated. The first heating furnace 620 is provided therein with a burner 500 to heat the air existing in the first heating furnace 620 to a high temperature, and the second heating furnace 630 is adapted to communicate with the first heating furnace 620 to allow the heated air to be supplied. Accordingly, the air heated by the first heating furnace 620 is introduced into the second heating furnace 630, thereby heating the heating chamber 610. The contaminated soil in the heating chamber 610 is indirectly heated, allowing pyrolysis gases to escape. Alternatively, in the case where it is not necessary to provide the separate first and

second heating furnaces

620 and 630, the burner 500 may be directly installed at the second heating furnace 630 so as to heat the air required for indirectly heating the heating chamber 610. Since the contaminated soil is heated at a high temperature in the pyrolysis apparatus 600, the pyrolysis gas may be partially oxidized, resulting in the inclusion of carbides. Therefore, in order to ensure complete combustion of the offgas and the pyrolysis gas in the burner 500, the foreign matter removal unit 700 for removing dust is installed on the pyrolysis gas lines HL1, HL2, and HL 3. In this case, the foreign material removal unit 700 may be implemented as a centrifugal type dust collector, and may also be implemented as a gas scrubber for spraying water to remove foreign materials contained in the pyrolysis gas, a filter dust collector for separating dust contained in the pyrolysis gas, an activated carbon filter for removing foreign materials remaining in the pyrolysis gas, or the like. In other words, the foreign material removal unit 700 may be implemented in any of various forms without departing from the scope of the present disclosure, as long as it can remove foreign materials, such as inert materials, environmental pollutants, etc., thereby purifying pyrolysis gas into a state in which it can be completely combusted. The pyrolysis gas having undergone the foreign matter removal stage is again forcibly transferred to the first heating furnace 620 by the transfer fan 800, and the burner 500 is installed in the first heating furnace 620. The transfer fan 800 is adapted to effectively blow pyrolysis gas separated from the pyrolysis apparatus 600 and supply an appropriate amount of pyrolysis gas to allow a continuous combustion operation of the burner 500. As a result, the burner 500 burns a mixed gas of the offgas supplied through the combustion gas line FL and the pyrolysis gas supplied through the pyrolysis gas lines HL1, HL2, and HL 3. The burner 500 further includes an auxiliary fuel tank 510 for driving the burner 500. The auxiliary fuel tank 510 is used to supply fuel required for initial ignition to the burner 500. That is, when the combustion temperature of the burner 500 is decreased, the auxiliary fuel tanks 510 supply fuel to compensate for the decreased temperature, respectively. Subsequently, the cleaned soil, which is a product generated by the thermal decomposition in the pyrolysis apparatus 600, is discharged to the outside through the transfer device. However, since the cleaned soil just discharged from the pyrolysis apparatus 600 has a high temperature, there is a risk that the cleaned soil is exposed to the outside without delay. Therefore, it is preferable that the cleaned soil discharged from the pyrolysis apparatus 600 is transferred to the cooled separate cooling device 920 and then discharged to the outside.

Although the cooling device 920 may be operated in any of various manners, such as an air cooling manner and a water cooling manner, the cooling device 920 according to the present soil purification system is preferably operated in water cooling. The water-cooled cooling apparatus 920 is preferably operated in such a manner that a spraying device such as a sprinkler sprays cooling water from above the purified soil over a large area. Spraying is performed to prevent the purified soil in a dry and heated state from being splashed or splashed as soil, sand or dust, thereby preventing unnecessary diffusion of the purified soil. The cooling apparatus 920 may further include a transfer portion 921 adapted to transfer the cleaned soil in a spiral manner to improve transfer efficiency of the cleaned soil discharged from the pyrolysis apparatus 600. The exhaust gas from the burner 500 has been used to heat the heating chamber 610 of the pyrolysis apparatus 660, and is discharged to the outside through the exhaust lines EL1, EL2, and EL 3. Meanwhile, since the exhaust gas is a product resulting from combustion of the exhaust gas and the pyrolysis gas as pollutants, it may contain some dust and/or ash. Therefore, before being discharged to the outside, the exhaust gas preferably passes through the filter 910, the filter 910 filters out the powder dust and the dust, and then is discharged to the outside at high altitude through the stack, and in order to improve the discharge efficiency of the exhaust gas passing through the stack 913, the exhaust gas having passed through the filter 910 may be compressed. The dust and/or ash filtered by the filter 910 are separately collected and separately treated by the transfer device 911, and the exhaust gas having passed through the filter 910 is compressed using a separate drainage device 912 (e.g., a drainage pump). Since the exhaust gas is maintained at a high temperature even after being discharged from the pyrolysis apparatus 600, it is economical to utilize high-temperature energy in other applications. For example, high temperature energy may be used to drive a waste boiler 930, which is used to heat rooms and water, and the waste boiler 930 may be used to improve indoor conditions in the space where the contaminated soil purification system is located. The invention is installed. The reuse of exhaust gas is not necessarily limited to the above-described application, and may be applied to various uses if necessary.

As can be seen from the above embodiments, the present invention has the advantages that:

The present invention has been described in detail with reference to the specific embodiments, but the present invention is not limited to the specific embodiments described above, and is only exemplary. Any equivalent modifications and substitutions are within the scope of the present invention for those skilled in the art. Accordingly, variations and modifications in equivalents may be made without departing from the spirit and scope of the invention, which is intended to be covered by the following claims.

Claims

1. The utility model provides a soil thermal desorption clean system, its characterized in that, including letter sorting equipment, desicator, condenser, component ratio the control unit, combustor, pyrolysis equipment and the cooling arrangement who connects gradually, one side of condenser is equipped with the cooling tower, the pyrolysis device includes first heating furnace, second heating furnace and pyrolysis gas pipeline, it gets rid of unit and conveying fan to have arranged the foreign matter on the pyrolysis gas pipeline, the desicator is including shifting part and microwave generation part, be equipped with rotatable heating chamber in the second heating furnace.

2. The soil thermal desorption purification system of claim 1, wherein a dryness check portion and a bypass are provided at an outlet of the dryer, one end of the bypass is connected to a transfer device leading to the pyrolysis device, and the other end of the bypass is connected to a transfer device leading to a starting point of the dryer.

3. The soil thermal desorption decontamination system of claim 1, wherein said burner includes an auxiliary fuel tank.