阅读说明：本技术 一种用于热脱附系统尾气除尘脱硫的装置及方法 (Device and method for dedusting and desulfurizing tail gas of thermal desorption system ) 是由 邵志国 许世佩 许毓 刘龙杰 于 2020-05-19 设计创作，主要内容包括：本发明提供一种用于热脱附系统尾气除尘脱硫的装置及方法,该装置包括设置有进气管道及排气管道的立式箱体,立式箱体内部设置有若干过滤筛网、若干脱硫剂滤网,若干过滤筛网、若干脱硫剂滤网将立式箱体沿其长度方向划分为若干区域,且第一区域及第二区域由过滤筛网划分而成；若干区域内分别设置有隔板,其分别将若干区域自上至下划分为若干个区块,由过滤筛网划分的相邻区域内所设置的隔板将若干过滤筛网划分为若干过滤筛网段,以使脱附气体沿着螺旋形通道依次流经过滤筛网的各段；由脱硫剂滤网划分的相邻区域内所设置的隔板将若干脱硫剂滤网划分为若干脱硫剂滤网段,以使经过滤筛网过滤除尘后的脱附气体沿着螺旋形通道依次流经脱硫剂滤网的各段。(The invention provides a device and a method for dedusting and desulfurizing tail gas of a thermal desorption system, wherein the device comprises a vertical box body provided with an air inlet pipeline and an exhaust pipeline, a plurality of filter screens and a plurality of desulfurizer filter screens are arranged in the vertical box body, the vertical box body is divided into a plurality of areas along the length direction of the vertical box body by the filter screens and the desulfurizer filter screens, and the first area and the second area are formed by dividing the filter screens; the plurality of areas are respectively provided with a clapboard which divides the plurality of areas into a plurality of blocks from top to bottom, and the plurality of filter screens are divided into a plurality of filter screen segments by the clapboards arranged in the adjacent areas divided by the filter screens, so that desorption gas sequentially flows through each segment of the filter screens along the spiral channel; the partition plates arranged in the adjacent areas divided by the desulfurizer filter screens divide the desulfurizer filter screens into desulfurizer filter screen segments, so that the desorbed gas filtered and dedusted by the filter screens sequentially flows through the segments of the desulfurizer filter screens along the spiral channel.)

1. The utility model provides a device for thermal desorption system tail gas dust removal desulfurization which characterized in that, a device for thermal desorption system tail gas dust removal desulfurization includes: the vertical type box body is internally provided with a plurality of filter screens and a plurality of desulfurizer filter screens, the filter screens and the desulfurizer filter screens divide the vertical type box body into a plurality of areas along the length direction of the vertical type box body, and the first area and the second area are formed by dividing the filter screens;

the plurality of areas are respectively provided with a partition board which divides the plurality of areas into a plurality of blocks from top to bottom, and the plurality of filter screens are divided into a plurality of filter screen segments by the partition boards arranged in the adjacent areas divided by the filter screens, so that desorption gas sequentially flows through the segments of the filter screens along the spiral channel; the partition plates arranged in adjacent areas divided by the desulfurizer filter screens divide a plurality of desulfurizer filter screens into a plurality of desulfurizer filter screen segments, so that desorbed gas filtered and dedusted by the filter screens sequentially flows through all the segments of the desulfurizer filter screens along a spiral channel;

the vertical box body is provided with an air inlet pipeline and an exhaust pipeline.

2. The device according to claim 1, wherein when the number of the plurality of regions is odd, a middle partition plate is arranged in an even region, and the middle partition plate divides the block above the lowest partition plate in the even region into two parts along the length direction of the block;

when the number of the areas is an even number, the even number areas except the last area are internally provided with the middle partition plates, and the middle partition plates divide the blocks above the lowest partition plate in the even number areas except the last area into two parts along the length direction of the blocks.

3. The apparatus according to claim 1 or 2, wherein N partitions are disposed in a plurality of said zones, respectively, and divide the plurality of said zones into N +1 blocks from top to bottom, respectively, and wherein the partitions disposed in adjacent zones divided by the filter screens divide the plurality of said filter screens into 2N +1 filter screen segments, so that the desorption gas flows through the segments of the filter screens in sequence along the spiral path; the partition plates arranged in the adjacent areas divided by the desulfurizer filter screens divide a plurality of desulfurizer filter screens into 2N +1 desulfurizer filter screen sections, so that desorption gas filtered and dedusted by the filter screens sequentially flows through the sections of the desulfurizer filter screens along the spiral channel.

4. The device according to claim 1 or 2, wherein the mesh diameters of a plurality of the filter mesh sections are gradually reduced along with the sequence of the tail gas of the thermal desorption system, or the particle diameters of the filter materials filled in a plurality of the filter mesh sections are gradually reduced along with the sequence of the tail gas of the thermal desorption system.

5. The apparatus of claim 1 or 2, wherein the filter screen is a metal filter screen.

6. The device according to claim 1 or 2, wherein the particle size of the filter material in the plurality of desulfurizer filter screen segments is gradually reduced along with the sequence of tail gas flowing through the thermal desorption system.

7. The device according to claim 1 or 2, characterized in that the thickness of the filter screen is 10-15mm and the thickness of the desulfurizer filter screen is 15-20 mm.

8. The device according to claim 1 or 2, characterized in that the device is further provided with a differential pressure gauge, wherein pressure detection probes thereof are respectively arranged in the lowermost zone of the plurality of zones.

9. The device according to claim 1 or 2, characterized in that it is further provided with thermometers, whose thermocouples are respectively arranged in the lowermost zone of several of said zones.

10. The device according to claim 1 or 2, wherein the front side or the rear side of the vertical box is provided with a plurality of filter screen drawing openings and a plurality of desulfurizer screen drawing openings respectively.

11. The apparatus according to any one of claims 1-10, wherein among a number of said zones, an odd number of zones are provided with electric heating tubes, and wherein said electric heating tubes extend helically through said odd number of zones.

12. A thermal desorption system comprises a material storage unit, a thermal desorption reaction device, a tail gas dedusting unit, a tail gas condensing unit, a non-condensable gas processing unit, an oil-water separation unit and a sewage processing unit, and is characterized in that the system further comprises the device for dedusting and desulfurizing the tail gas of the thermal desorption system according to any one of claims 1 to 11, the device is positioned between the tail gas dedusting unit and the tail gas condensing unit, and an air inlet pipeline and an air outlet pipeline of the device are respectively connected with a gas outlet of the tail gas dedusting unit and a gas inlet of the tail gas condensing unit through pipelines.

13. A method for dedusting and desulfurizing tail gas of a thermal desorption system, which is characterized by utilizing the device for dedusting and desulfurizing tail gas of a thermal desorption system as claimed in any one of claims 1-11, and comprises the following steps:

(1) the desorption gas after being preliminarily dedusted by a tail gas dedusting unit of a thermal desorption system enters the device through a gas inlet pipeline of the device, and in the device, the desorption gas sequentially flows through all sections of a filter screen along a spiral channel so as to carry out filtering and dedusting step by step with a plurality of times of filtering degrees enhanced step by step;

(2) the desorption gas after being filtered and dedusted sequentially flows through each section of the desulfurizer filter screen along the spiral channel to be subjected to gradual desulfurization treatment with a plurality of degrees enhanced section by section, and in the gradual desulfurization treatment process with a plurality of degrees enhanced section by section, the desorption gas after being desulfurized sequentially flows through each section of the filter screen along the spiral channel to be subjected to gradual filtering and dedusting with a plurality of times of filtering degrees enhanced section by section;

(3) and (3) repeating the desulfurization treatment and the filtering and dedusting in the step (2) until the tail gas of the thermal desorption system reaches the standard and is discharged.

14. The method according to claim 13, wherein the desorption gas is maintained at a temperature 10-30 ℃ higher than the desorption gas inlet temperature in steps (1) - (3).

15. The method of claim 13, wherein the filter screen needs to be replaced when the pressure differential between the lowermost zones of adjacent regions of the device divided by the filter screen is greater than 200 and 800 Pa.

16. The method as claimed in claim 13, wherein the desulfurizer filter screen is replaced when the pressure difference between the lowermost zones of adjacent zones of the apparatus divided by the desulfurizer filter screen is higher than 800-1200Pa or the concentration of sulfide in the gas discharged from the exhaust duct exceeds a standard.

17. The method according to claim 13, characterized in that the residence time of the desorption gas in the device is 1.2-3.2 s.

18. The method according to any one of claims 13 to 17, wherein the desorption gas flows through a filter screen and a desulfurizer screen at a flow rate of 6 to 12 m/s.

Technical Field

The invention relates to a device and a method for dedusting and desulfurizing tail gas of a thermal desorption system, belonging to the technical field of oil-containing solid waste recycling treatment in the petrochemical industry.

Background

The thermal desorption technology is originally applied to dry distillation and petroleum cracking of coal and wood, and is applied to the fields of oil-containing solid waste treatment and high-concentration organic contaminated soil remediation. In the process of thermal desorption of the oil-containing solid waste, distillation and thermal decomposition exist at the same time, and the oil-containing solid waste is heated to a certain temperature under the anaerobic condition to decompose hydrocarbons and organic matters, so that the oil-containing solid waste is converted into three phase substances: the gas phase is non-condensable gas such as methane, carbon monoxide and the like; the liquid phase mainly comprises thermal desorption oil and water; the solid phase is inorganic mineral matter and carbon residue. Generally speaking, the thermal desorption process mainly comprises a material storage unit, a thermal desorption reaction device, a tail gas dedusting unit, a tail gas condensing unit, a non-condensable gas treatment unit, an oil-water separation unit and a sewage treatment unit. The method can be divided into electromagnetic heating, fuel oil heating, fuel gas heating and high-temperature flue gas heating according to different heat sources; direct heating, indirect heating, direct-indirect combination and direct flame heating can be classified according to the heating mode; it can be divided into a spiral type desorption furnace and a rotary kiln type desorption furnace according to the furnace type structure. At present, oil sludge thermal desorption treatment engineering projects are built in Daqing oil fields, Xinjiang oil fields and other fields, and organic contaminated soil thermal desorption restoration projects are built in Chongqing fields, Shanghai fields and other fields.

However, in practical application, because the oily solid waste contains a large amount of sulfur-containing substances, the oily solid waste can be evaporated and removed together with oil gas in a thermal desorption process to enter a gas phase, the sulfur content of tail gas discharged after non-condensable gas incineration treatment exceeds the standard and cannot be normally discharged, and sulfide is dissolved in condensed oil, so that the peculiar smell of recovered oil is large, and mineral oil is difficult to recycle. In addition, desorption gas contains a large amount of dust and easily blocks up the condensing system and the supporting pipeline of rear end, and the dust collection efficiency of the cyclone dust collector commonly adopted at present is generally about 60%, and efficient wet water spraying condensation process needs to consume a large amount of cooling water, and the subsequent treatment burden of the produced oily wastewater is heavier, so that the problems of efficient dust removal, desulfurization and peculiar smell removal of thermal desorption gas are the technical problems to be solved urgently in the thermal desorption treatment technology of oily solid waste.

In summary, it has become an urgent technical problem in the art to provide a novel device and method for dust removal and desulfurization of tail gas from a thermal desorption system.

Disclosure of Invention

In order to solve the above disadvantages and shortcomings, an object of the present invention is to provide a device for dust removal and desulfurization of tail gas of a thermal desorption system.

It is also an object of the present invention to provide a thermal desorption system.

The invention also aims to provide a method for dedusting and desulfurizing tail gas of the thermal desorption system.

In order to achieve the above object, in one aspect, the present invention provides an apparatus for dust removal and desulfurization of tail gas of a thermal desorption system, wherein the apparatus for dust removal and desulfurization of tail gas of a thermal desorption system comprises:

the vertical type box body is internally provided with a plurality of filter screens and a plurality of desulfurizer filter screens, the filter screens and the desulfurizer filter screens divide the vertical type box body into a plurality of areas along the length direction of the vertical type box body, and the first area and the second area are formed by dividing the filter screens;

the plurality of areas are respectively provided with a partition board which divides the plurality of areas into a plurality of blocks from top to bottom, and the plurality of filter screens are divided into a plurality of filter screen segments by the partition boards arranged in the adjacent areas divided by the filter screens, so that desorption gas sequentially flows through the segments of the filter screens along the spiral channel; the partition plates arranged in adjacent areas divided by the desulfurizer filter screens divide a plurality of desulfurizer filter screens into a plurality of desulfurizer filter screen segments, so that desorbed gas filtered and dedusted by the filter screens sequentially flows through all the segments of the desulfurizer filter screens along a spiral channel;

the vertical box body is provided with an air inlet pipeline and an exhaust pipeline.

In the device, except that the first area and the second area are formed by dividing the filter screen, the invention does not make specific requirements on the arrangement sequence of other filter screens and desulfurizer screens, and technicians in the field can reasonably select the arrangement quantity and the arrangement sequence of the filter screens and the desulfurizer screens according to the requirements of field dust removal and desulfurization treatment, such as desorption gas quantity to be treated, dust in gas, sulfide concentration and the like; and the invention can realize better dust removal and desulfurization by arranging a plurality of filter screens and a desulfurizer filter screen.

In the above device, preferably, when the number of the plurality of regions is odd, a middle partition is disposed in an even region (such as the second region, the fourth region, etc.), and the middle partition divides the block above the lowest partition in the even region into two parts along the length direction of the block;

when the number of the areas is an even number, the even number areas except the last area are internally provided with the middle partition plates, and the middle partition plates divide the blocks above the lowest partition plate in the even number areas except the last area into two parts along the length direction of the blocks.

In the above-mentioned apparatus, preferably, N partition plates are respectively disposed in a plurality of the regions, and divide the plurality of the regions into N +1 blocks from top to bottom, and the partition plates disposed in adjacent regions divided by the filter screen divide the plurality of the filter screen into 2N +1 filter screen segments, so that the desorption gas sequentially flows through the segments of the filter screen along the spiral channel; the partition plates arranged in the adjacent areas divided by the desulfurizer filter screens divide a plurality of desulfurizer filter screens into 2N +1 desulfurizer filter screen sections, so that desorption gas filtered and dedusted by the filter screens sequentially flows through the sections of the desulfurizer filter screens along the spiral channel.

Wherein N is a positive integer.

In the above apparatus, preferably, the aperture of the sieve mesh of the plurality of filter sieve mesh segments is gradually reduced along with the sequence of the tail gas of the thermal desorption system flowing through, or the particle size of the filter material filled in the plurality of filter sieve mesh segments is gradually reduced along with the sequence of the tail gas of the thermal desorption system flowing through.

In the above-described apparatus, preferably, the filter screen is a metal filter screen.

In the above apparatus, preferably, the particle sizes of the filter materials in the plurality of desulfurizer filter screen segments are gradually reduced along with the sequence of the tail gas flowing through the thermal desorption system.

In the device, the higher number of filter screen and desulfurizer filter screen segments can further prolong the filtering time and the adsorption time and improve the dust removal and desulfurization efficiency.

In the above device, preferably, the thickness of the filter screen is 10-15mm, and the thickness of the desulfurizer filter screen is 15-20 mm.

Preferably, the device is further provided with a differential pressure gauge, and pressure detection probes of the differential pressure gauge are respectively arranged in the lowest blocks of the plurality of zones.

Preferably, the device is further provided with thermometers, the thermocouples of which are respectively arranged in the lowermost zone of the plurality of zones.

In the above device, preferably, the front side surface or the rear side surface of the vertical box body is respectively provided with a plurality of filter screen drawing openings and a plurality of desulfurizer filter screen drawing openings. The number of the filter screen drawing openings and the number of the desulfurizer filter screen drawing openings correspond to the number of the filter screens and the desulfurizer filter screens.

In the operation process, the filter screen and the desulfurizer filter screen can be respectively drawn out from the filter screen drawing opening and the desulfurizer filter screen drawing opening so as to periodically clean or replace the filter material.

In the above-mentioned device, preferably, among a plurality of the zones, an odd-numbered zone (e.g., the first zone, the third zone, etc.) is provided with an electric heating pipe, and the electric heating pipe spirally penetrates (needs to penetrate through the corresponding partition) the odd-numbered zone.

On the other hand, the invention also provides a thermal desorption system which comprises a material storage unit, a thermal desorption reaction device, a tail gas dust removal unit, a tail gas condensation unit, a non-condensable gas treatment unit, an oil-water separation unit and a sewage treatment unit, wherein the system also comprises the device for dust removal and desulfurization of the tail gas of the thermal desorption system, the device is positioned between the tail gas dust removal unit and the tail gas condensation unit, and an air inlet pipeline and an air outlet pipeline of the device are respectively connected with a gas outlet of the tail gas dust removal unit and a gas inlet of the tail gas condensation unit through pipelines.

The device for dedusting and desulfurizing the tail gas of the thermal desorption system is arranged between the tail gas dedusting unit and the tail gas condensing unit of the existing thermal desorption system, so that the gas dedusting efficiency can be further improved, sulfides in the flue gas can be synchronously removed, oil gas can be purified, the risk of blocking a subsequent condensing system and a matched pipeline can be reduced, and the standard of the sulfur content in the tail gas after the non-condensable gas is burnt can be ensured.

In another aspect, the present invention further provides a method for dust removal and desulfurization of tail gas of a thermal desorption system, where the method for dust removal and desulfurization of tail gas of a thermal desorption system utilizes the above apparatus for dust removal and desulfurization of tail gas of a thermal desorption system, and includes:

(1) the desorption gas after being preliminarily dedusted by a tail gas dedusting unit of a thermal desorption system enters the device through a gas inlet pipeline of the device, and in the device, the desorption gas sequentially flows through all sections of a filter screen along a spiral channel so as to carry out filtering and dedusting step by step with a plurality of times of filtering degrees enhanced step by step;

(2) the desorption gas after being filtered and dedusted sequentially flows through each section of the desulfurizer filter screen along the spiral channel to be subjected to gradual desulfurization treatment with a plurality of degrees enhanced section by section, and in the gradual desulfurization treatment process with a plurality of degrees enhanced section by section, the desorption gas after being desulfurized sequentially flows through each section of the filter screen along the spiral channel to be subjected to gradual filtering and dedusting with a plurality of times of filtering degrees enhanced section by section;

(3) and (3) repeating the desulfurization treatment and the filtering and dedusting in the step (2) until the tail gas of the thermal desorption system reaches the standard and is discharged.

In the above-described method, preferably, the desorption gas is maintained at a temperature 10 to 30 ℃ higher than the desorption gas inlet temperature in steps (1) to (3).

In the specific embodiment of the invention, the desorption gas entering the device can be heated and accompanied by heat through the electric heating pipe, so that the temperature of the desorption gas is kept 10-30 ℃ higher than the inlet temperature of the desorption gas.

In the above method, it is preferred that the filter screen needs to be replaced when the pressure difference between the lowermost zones of adjacent regions in the device divided by the filter screen is higher than 200-800 Pa.

In the above method, preferably, when the pressure difference between the lowermost zones of adjacent regions in the apparatus divided by the desulfurizer screen is higher than 800-.

Wherein a person skilled in the art can routinely determine whether the concentration of sulphide in the gas exiting the exhaust line is above a standard.

In the above-described process, the residence time of the desorption gas in the apparatus is preferably 1.2 to 3.2 s. In a particular embodiment of the invention, the residence time may be, for example, from 1.2 to 2.2s, from 1.5 to 2.5s and from 1.8 to 3.2 s.

In the above method, preferably, the flow rate of the desorption gas flowing through the filter screen and the desulfurizer filter screen is 6 to 12 m/s.

In the method, the filtering and dust removing process in the step (1) can be carried out for a plurality of times, after the filtering and dust removing are completed, the desorption gas after the filtering and dust removing is carried out for the desulfurization treatment in the step (2), the desulfurization treatment can also be carried out for a plurality of times, the desulfurization treatment process can be inserted for a plurality of times for filtering and dust removing, and the desulfurization treatment process can be inserted for a plurality of times again in the filtering and dust removing process for a plurality of times until the tail gas of the thermal desorption system reaches the standard and is discharged.

In the method, the used desulfurizer can be a conventional desulfurizer used in the field, and the desulfurizer is not specifically required in the application, so that a person skilled in the art can reasonably select the desulfurizer according to the field operation requirement as long as the aim of desulfurization can be fulfilled; as in one embodiment of the present invention, the desulfurizing agent used is solid calcium oxide.

In the invention, the filter screen can adopt a metal filter screen and can also be filled with filter materials with different particle sizes, the function of the filter screen is to remove dust in desorption gas, and the mesh number or the filter precision of each section of filter screen can be controlled and adjusted according to the property of the treated material and the pressure balance of a pipeline system; the desulfurizer in the desulfurizer filter screen can be properly adjusted according to the property of the treated material, and the particle size of the desulfurizer influences the pressure difference before and after filtration and the retention time in the desulfurizer filter material, and needs to be adjusted and set in combination with the pressure difference resistance of a system pipeline and the sulfur concentration in desorption gas.

The device provided by the invention can be used for high-efficiency synchronous dust removal and desulfurization of thermal desorption gas, can further improve the gas dust removal efficiency on the basis of dust removal of the existing tail gas dust removal unit such as a cyclone dust remover, synchronously removes sulfides in flue gas and purifies oil gas, and has the following advantages:

the adoption of filtration type dust removal improves the dust removal efficiency of the prior art, can avoid the risk of blocking a subsequent condensation system and a matched pipeline, and ensures the continuous and stable operation of a thermal desorption system.

And the desulfurization treatment is carried out before the condensation of the desorption gas, so that the sulfur content in the non-condensable gas is reduced, and the sulfur content in the finally discharged tail gas is ensured to reach the standard.

Filter screen adopts pull formula design, and the dust reaches the certain degree in holding back gas, can dismantle the filter screen and sweep or change, divide into a plurality of sections with filter screen through setting up the baffle, can make gas pass through in spiral cavity passageway in order, has increased gaseous filtration frequency through filter screen, has prolonged the adsorption time when the gas flow passes through the desulfurizer.

The desulfurizer filter screen adopts the design of pull formula, and after adsorbing the sulphide saturation, convenient to detach changes the desulfurizer, divide into a plurality of sections with the desulfurizer filter screen through setting up the baffle, can make gas pass through in spiral cavity passageway in order, has increased the contact time of adsorbent and sulphide, promotes the desorption to sulphide in the gas.

Through setting up electric heating pipe, control and maintain the temperature in the dust removal desulfurization integrated device, prevent to filter and desulfurization in-process flue gas temperature decline and cause oil gas condensation coking jam.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings needed to be used in the description of the embodiments will be briefly introduced below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and it is obvious for those skilled in the art that other drawings can be obtained according to these drawings without creative efforts.

Fig. 1a is a top view of an apparatus for dust removal and desulfurization of tail gas of a thermal desorption system provided in embodiment 1 of the present invention.

Fig. 1b is a sectional view taken along line a-a of the apparatus for dedusting and desulfurizing tail gas of a thermal desorption system in accordance with example 1 of the present invention.

Fig. 1c is a sectional view of the device for dedusting and desulfurizing tail gas of a thermal desorption system in accordance with embodiment 1 of the present invention, taken along line B-B.

Fig. 1d is a schematic structural diagram of a filter screen and a desulfurizer filter screen used in the device for dust removal and desulfurization of tail gas of a thermal desorption system according to embodiment 1 of the present invention.

The main reference numbers illustrate:

1. an air intake duct;

2. filtering the screen;

3. a desulfurizer filter screen;

4. an electric heating tube;

5. a partition plate;

51. a first separator;

52. a second separator;

53. a middle partition plate;

54. a third partition plate;

6. an exhaust duct;

7. a section of filter screen;

8. a second section of filtering screen;

9. three sections of filtering screens;

10. three sections of desulfurizer filter screens;

11. a second section of desulfurizer filter screen;

12. a section of desulfurizer filter screen;

13. a differential pressure gauge;

131. a first pressure probe;

132. a second pressure probe;

133. a third pressure probe;

14. a thermometer;

141. a thermocouple;

15. the filter screen draws the opening;

16. a desulfurizer filter screen drawing opening;

A. a first region;

B. a second zone;

C. and (4) a third area.

Detailed Description

In order to clearly understand the technical features, objects and advantages of the present invention, the following detailed description of the technical solutions of the present invention will be made with reference to the following specific examples, which should not be construed as limiting the implementable scope of the present invention.

It should be noted that the term "comprises/comprising" and any variations thereof in the description and claims of this invention and the above-described drawings is intended to cover a non-exclusive inclusion, such that a process, method, system, article, or apparatus that comprises a list of steps, components, or elements does not have to be limited to those steps, components, or elements expressly listed but may include other steps, components, or elements not expressly listed or inherent to such process, method, system, article, or apparatus.

In the present invention, the terms "upper", "lower", "left", "right", "front", "rear", "middle", and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings. These terms are used primarily to better describe the invention and its embodiments and are not intended to limit the indicated devices, elements or components to a particular orientation or to be constructed and operated in a particular orientation.

Moreover, some of the above terms may be used to indicate other meanings besides the orientation or positional relationship, for example, the term "on" may also be used to indicate some kind of attachment or connection relationship in some cases. The specific meanings of these terms in the present invention can be understood by those skilled in the art as appropriate.

Furthermore, the terms "disposed" and "connected" should be interpreted broadly. The specific meanings of the above terms in the present invention can be understood by those of ordinary skill in the art according to specific situations.

Example 1

This embodiment provides an apparatus for dust removal and desulfurization of tail gas in a thermal desorption system, which is shown in fig. 1 a-1 c in a top view, a sectional view a-a and a sectional view B-B, respectively, and as can be seen from fig. 1 a-1 c, the apparatus includes:

the vertical type box body is internally provided with a filter screen 2 and a desulfurizer filter screen 3, and the filter screen 2 and the desulfurizer filter screen 3 divide the vertical type box body into a first area A, a second area B and a third area C along the length direction of the vertical type box body;

a first partition plate 51 is arranged in the first area A, and divides the first area A into 2 blocks from top to bottom, wherein the two blocks of the first area A are respectively marked as a block I and a block III;

a second partition plate 52 is arranged in the second area B, divides the second area B into 2 blocks from top to bottom, marks the block below the second area B as a block IV, and is also provided with a middle partition plate 53, divides the block above the second area B into a left block and a right block along the length direction of the left block and the right block, wherein the left block and the right block are respectively marked as a block II and a block VI;

the first partition plate 51 arranged in the first zone a and the second partition plate 52 arranged in the second zone B (wherein the height of the first partition plate 51 is higher than that of the second partition plate 52) divide the filtering screen 2 into 3 sections from top to bottom, which are respectively marked as a first section filtering screen 7, a second section filtering screen 8 and a third section filtering screen 9, as shown in fig. 1 d;

a third partition plate 54 is arranged in the three zones C, and divides the three zones C into 2 blocks from bottom to top, wherein the 2 blocks are respectively marked as a block V and a block VII;

the second partition plate 52 arranged in the second zone B and the third partition plate 54 arranged in the third zone C (wherein the height of the third partition plate 54 is higher than that of the second partition plate 52) divide the desulfurizer filter screen 3 into 3 sections from bottom to top, which are respectively marked as a first section desulfurizer filter screen 12, a second section desulfurizer filter screen 11 and a third section desulfurizer filter screen 10, and desulfurizers are filled in the first section desulfurizer filter screen to the third section desulfurizer filter screen, as shown in fig. 1 d;

the left side wall of the upper block (block I) of the first area A is provided with an air inlet pipeline 1, and the right side wall of the upper block (block VI) of the third area C is provided with an exhaust pipeline 6;

in this embodiment, the screen mesh diameters of the first-stage filter screen 7, the second-stage filter screen 8 and the third-stage filter screen 9 are gradually reduced, that is, the first-stage filter screen 7, the second-stage filter screen 8 and the third-stage filter screen 9 are respectively a large-hole screen, a medium-hole screen and a small-hole screen;

in this embodiment, the particle size of the filter material (desulfurizer) in the first section of desulfurizer filter screen 12, the second section of desulfurizer filter screen 11 and the third section of desulfurizer filter screen 10 is gradually reduced, that is, the first section of desulfurizer filter screen 12, the second section of desulfurizer filter screen 11 and the third section of desulfurizer filter screen 10 are respectively large particle size filler, medium particle size filler and small particle size filler;

in this embodiment, the apparatus is further provided with a differential pressure gauge 13, wherein a first pressure probe 131, a second pressure probe 132 and a third pressure probe 133 of the differential pressure gauge are respectively arranged in the block iii, the block iv and the block v;

in this embodiment, the apparatus is further provided with a thermometer 14, wherein thermocouples are respectively disposed in the block iii, the block iv and the block v (only the thermocouple 141 is shown disposed in the block v);

in this embodiment, the rear side surface of the vertical box is respectively provided with a filter screen drawing opening 15 and a desulfurizer filter screen drawing opening 16;

in this embodiment, the electric heating tubes 4 are respectively disposed in the first zone a and the third zone C, and the electric heating tubes 4 spirally penetrate through the first zone a and the third zone C (the electric heating tubes 4 respectively penetrate through the first partition plate 51 and the third partition plate 54), that is, the electric heating tubes 4 spirally penetrate through the first partition plate 51 and the third partition plate 54 and are disposed in the block i and the block iii, and the block vii and the block v, and the starting ends of the electric heating tubes 4 are respectively fixed on the rear side wall of the box body.

Example 2

This embodiment provides a thermal desorption system, including material storage unit, thermal desorption reaction unit, tail gas dust removal unit, tail gas condensing unit, noncondensable gas processing unit, oil-water separation unit and sewage treatment unit, wherein, the system still includes the desulfurated device of thermal desorption system tail gas dust removal that is used for that provides in above embodiment 1, the device is located between tail gas dust removal unit and the tail gas condensing unit, admission line, the exhaust duct of device link to each other through gas outlet, the gas inlet of tail gas condensing unit of pipeline and tail gas dust removal unit respectively.

The device for dedusting and desulfurizing the tail gas of the thermal desorption system provided by the embodiment 1 of the invention is arranged between the tail gas dedusting unit and the tail gas condensing unit of the existing thermal desorption system, so that the gas dedusting efficiency can be further improved, sulfides in the flue gas can be synchronously removed, the oil gas can be purified, the risk of blocking a subsequent condensing system and a matched pipeline can be reduced, and the standard sulfur content in the tail gas after the non-condensable gas is burnt can be ensured.

Example 3

The embodiment provides a method for dedusting and desulfurizing tail gas of a thermal desorption system, wherein the method for dedusting and desulfurizing tail gas of the thermal desorption system utilizes the device for dedusting and desulfurizing tail gas of the thermal desorption system provided in the above embodiment 1, and comprises the following specific steps:

(1) carrying out thermal desorption treatment on the oil-based drilling cuttings by using a thermal desorption reaction device of a thermal desorption system to generate desorption gas, and carrying out primary dust removal on the desorption gas by using a tail gas dust removal unit of the thermal desorption system, wherein the property parameters of the oil-based drilling cuttings are shown in the following table 1;

TABLE 1

Properties of	Oil content (wt%)	Water content (wt%)	Solid content (wt%)
				Oil-based drill cuttings	14.75	5.10	80.15

(2) The desorption gas after primary dust removal of a tail gas dust removal unit (such as a cyclone dust collector) of a thermal desorption system enters the device through an air inlet pipeline of the device under the suction action of a rear-end induced draft fan, the temperature in the box body of the device is controlled to be 280 ℃, and in the device, the desorption gas sequentially flows through all sections of a filter screen along a spiral channel so as to carry out filtering and dust removal step by step with the filtering degree enhanced step by step;

in the embodiment, the thickness of the filtering screen is 10-15 mm; the first-stage filtering screen 7, the second-stage filtering screen 8 and the third-stage filtering screen 9 are all metal screens, and the apertures of the metal screens are 10-30 meshes, 25-50 meshes and 40-60 meshes respectively;

(3) the desorbed gas after being filtered and dedusted sequentially flows through each section of a desulfurizer filter screen along a spiral channel to perform gradual desulfurization treatment with gradually enhanced degree;

in the embodiment, the thickness of the desulfurizer filter screen is 15-20 mm; the first section of desulfurizer filter screen 12, the second section of desulfurizer filter screen 11 and the third section of desulfurizer filter screen 10 are filled with pellets made of solid calcium oxide, and the particle size of the pellets made of the solid calcium oxide in each section is 8-12mm, 5-8mm and 2-5mm respectively; the flow velocity of the gas flowing through the filter screen and the desulfurizer filter screen is 8-12 m/s;

in this example, the residence time of the desorbed gas in the apparatus is 1.2-2.2 s.

Example 4

The embodiment provides a method for dedusting and desulfurizing tail gas of a thermal desorption system, wherein the method for dedusting and desulfurizing tail gas of the thermal desorption system utilizes the device for dedusting and desulfurizing tail gas of the thermal desorption system provided in the above embodiment 1, and comprises the following specific steps:

(1) carrying out thermal desorption treatment on the petroleum-polluted soil by using a thermal desorption reaction device of a thermal desorption system to generate desorption gas, and carrying out primary dust removal on the desorption gas by using a tail gas dust removal unit of the thermal desorption system, wherein the property parameters of the petroleum-polluted soil are shown in the following table 2;

TABLE 2

Properties of	Oil content (wt%)	Water content (wt%)	Solid content (wt%)
				Oil contaminated soil	9.38	16.24	74.38

(2) The desorption gas after primary dust removal of a tail gas dust removal unit (such as a cyclone dust collector) of a thermal desorption system enters the device through an air inlet pipeline of the device under the suction action of a rear-end induced draft fan, the temperature in the box body of the device is controlled to be 320 ℃, and in the device, the desorption gas sequentially flows through all sections of a filter screen along a spiral channel so as to carry out filtering and dust removal step by step with the filtering degree enhanced step by step;

in the embodiment, the thickness of the filtering screen is 10-15 mm; the first-stage filter screen, the second-stage filter screen and the third-stage filter screen are all metal screens, and the apertures of the metal screens are respectively 10-30 meshes, 25-50 meshes and 40-60 meshes;

(3) the desorbed gas after being filtered and dedusted sequentially flows through each section of a desulfurizer filter screen along a spiral channel to perform gradual desulfurization treatment with gradually enhanced degree;

in the embodiment, the thickness of the desulfurizer filter screen is 15-20 mm; the first section of desulfurizer filter screen, the second section of desulfurizer filter screen and the third section of desulfurizer filter screen are filled with pellets made of solid calcium oxide, and the particle size of the pellets made of the solid calcium oxide in each section is 8-12mm, 5-8mm and 2-5mm respectively; the flow velocity of the gas flowing through the filter screen and the desulfurizer filter screen is 8-12 m/s;

in this embodiment, the residence time of the desorbed gas in the apparatus is 1.5-2.5 s.

Example 5

The embodiment provides a method for dedusting and desulfurizing tail gas of a thermal desorption system, wherein the method for dedusting and desulfurizing tail gas of the thermal desorption system utilizes the device for dedusting and desulfurizing tail gas of the thermal desorption system provided in the above embodiment 1, and comprises the following specific steps:

(1) carrying out thermal desorption treatment on the oily sludge by using a thermal desorption reaction device of a thermal desorption system to generate desorption gas, and carrying out primary dust removal on the desorption gas by using a tail gas dust removal unit of the thermal desorption system, wherein the property parameters of the oily sludge are shown in the following table 3;

TABLE 3

Properties of	Oil content (wt%)	Water content (wt%)	Solid content (wt%)
				Oily sludge	15.74	25.33	58.93

(2) The desorption gas after primary dust removal of a tail gas dust removal unit (such as a cyclone dust collector) of a thermal desorption system enters the device through an air inlet pipeline of the device under the suction action of a rear-end induced draft fan, the temperature in the box body of the device is controlled to be 350 ℃, and in the device, the desorption gas sequentially flows through all sections of a filter screen along a spiral channel so as to carry out filtering and dust removal step by step with the filtering degree enhanced step by step;

in the embodiment, the thickness of the filtering screen is 10-15 mm; the first-stage filter screen, the second-stage filter screen and the third-stage filter screen are all metal screens, and the apertures of the metal screens are respectively 10-30 meshes, 25-50 meshes and 40-60 meshes;

(3) the desorbed gas after being filtered and dedusted sequentially flows through each section of a desulfurizer filter screen along a spiral channel to perform gradual desulfurization treatment with gradually enhanced degree;

in the embodiment, the thickness of the desulfurizer filter screen is 15-20 mm; the first section of desulfurizer filter screen, the second section of desulfurizer filter screen and the third section of desulfurizer filter screen are filled with pellets made of solid calcium oxide, and the particle size of the pellets made of the solid calcium oxide in each section is 5-8mm, 2-5mm and 1-2mm respectively; the flow velocity of the gas flowing through the filter screen and the desulfurizer filter screen is 6-8 m/s;

in this example, the residence time of the desorbed gas in the apparatus is 1.8-3.2 s.

The device provided by the embodiment of the invention can be used for high-efficiency synchronous dust removal and desulfurization of thermal desorption gas, can further improve the gas dust removal efficiency on the basis of dust removal of the existing tail gas dust removal unit such as a cyclone dust collector, synchronously removes sulfides in flue gas, and purifies oil gas, and has the following advantages:

the adoption of filtration type dust removal improves the dust removal efficiency of the prior art, can avoid the risk of blocking a subsequent condensation system and a matched pipeline, and ensures the continuous and stable operation of a thermal desorption system.

And the desulfurization treatment is carried out before the condensation of the desorption gas, so that the sulfur content in the non-condensable gas is reduced, and the sulfur content in the finally discharged tail gas is ensured to reach the standard.

Filter screen adopts pull formula design, and the dust reaches the certain degree in holding back gas, can dismantle the filter screen and sweep or change, divide into a plurality of sections with filter screen through setting up baffle 5, can make gas pass through in spiral cavity passageway in order, has increased gaseous filtration frequency through filter screen, has prolonged the adsorption time when the gas flow passes through the desulfurizer.

The desulfurizer filter screen adopts the design of pull formula, and after adsorbing the sulphide saturation, convenient to detach changes the desulfurizer, divide into a plurality of sections with the desulfurizer filter screen through setting up baffle 5, can make gas pass through in spiral cavity passageway in order, has increased the contact time of adsorbent and sulphide, promotes the desorption to sulphide in the gas.

Through setting up electric heating pipe, control and maintain the temperature in the dust removal desulfurization integrated device, prevent to filter and desulfurization in-process flue gas temperature decline and cause oil gas condensation coking jam.

The above description is only exemplary of the invention and should not be taken as limiting the scope of the invention, so that the invention is intended to cover all modifications and equivalents of the embodiments described herein. In addition, the technical features and the technical inventions of the present invention, the technical features and the technical inventions, and the technical inventions can be freely combined and used.