CN109647113B - Dust removal, mist removal and white smoke elimination integrated system - Google Patents

Abstract

The invention discloses a dust and mist removing and white smoke removing integrated system, which comprises a dust and mist removing device and a plurality of surrounding heat exchangers, wherein the dust and mist removing device is arranged in a desulfurization absorption tower and/or a clean smoke flue, the surrounding heat exchangers are arranged to surround the outside of the desulfurization absorption tower and/or the clean smoke flue, the surrounding heat exchangers are arranged in series and/or in parallel, the surrounding heat exchangers are communicated with the dust and mist removing device, so that a heat exchange medium flows in the surrounding heat exchangers and exchanges heat with ambient air to cool, and the cooled heat exchange medium enters the dust and mist removing device and exchanges heat with saturated wet smoke to remove white smoke; the invention can perfectly combine the existing environment-friendly requirement of 'whitening' with the environment-friendly requirement of ultralow emission, and utilizes the high-efficiency dust-removing demisting device as the flue gas condensation in 'whitening', and simultaneously achieves the effect of removing wet flue gas fog drops and dust.

Description

Dust removal, mist removal and white smoke elimination integrated system

Technical Field

The invention relates to the field of flue gas purification, in particular to a dust and fog removal and white smoke removal integrated system which can be used for tail gas treatment systems of thermal power plants, steel plants, paper mills, glass plants, chemical plants and the like.

Background

When the existing coal-fired tail gas is discharged, a series of environment-friendly processes such as denitration, desulfurization, dust removal and the like are required. The existing main flow technology of flue gas desulfurization is wet desulfurization, the flue gas after wet desulfurization is saturated wet flue gas, and the phenomenon of white smoke can be generated when the flue gas is discharged to the atmosphere from the outside of a chimney. The existing dedusting, mist removing and whitening technology generally adopts a mode of spraying and cooling cold slurry in a single multilayer demister and a single tower, but the method has a plurality of defects: 1. spraying cold slurry is a common method for reducing the temperature of saturated flue gas, and although the temperature and the water content of the flue gas can be reduced, small slurry mist drops are discharged along with the flue gas due to cold slurry spraying, so that the dust content is higher; 2. the water content is reduced by simply spraying cold slurry so as to achieve the whitening effect, the application range of the method is narrow, the requirement on the environmental temperature and humidity is high, and the energy consumption is high and the economical efficiency is poor; 3. the independent multilayer demister structure is required, the occupied space is large, the structure and the implementation mode are unfavorable for flushing or cleaning, and after a period of operation, besides the corrosion problem, the equipment body also can generate the blockage and scaling problem.

Therefore, the person skilled in the art is dedicated to develop a dust-removing, mist-removing and smoke-eliminating integrated system with low energy consumption, low cost, high reliability and stable performance.

Disclosure of Invention

In view of the above-mentioned drawbacks of the prior art, the present invention aims to provide a dust-removing, mist-removing and smoke-eliminating integrated system with low energy consumption, low cost, high reliability and stable performance.

The invention provides a dust and mist removing and white smoke removing integrated system which comprises a dust and mist removing device and a plurality of surrounding heat exchangers, wherein the dust and mist removing device is arranged in a desulfurization absorption tower and/or a clean smoke flue, the surrounding heat exchangers are arranged to surround the outside of the desulfurization absorption tower and/or the clean smoke flue, the surrounding heat exchangers are arranged in series and/or in parallel, the surrounding heat exchangers are communicated with the dust and mist removing device, so that a heat exchange medium flows in the surrounding heat exchangers and exchanges heat with ambient air to cool, and the cooled heat exchange medium enters the dust and mist removing device and exchanges heat with saturated wet smoke to remove white smoke.

Further, the surrounding heat exchanger includes a heat exchange medium flow passage, an ambient air flow passage, and a spacing member for spacing the heat exchange medium flow passage and the ambient air flow passage and for exchanging heat between the heat exchange medium flow passage and the ambient air flow passage, the spacing member having a contact surface for exchanging heat with ambient air.

Further, the number of the spacer members is plural, and a plurality of repeating spacer member groups are formed, the spacer member groups include a first spacer member and a second spacer member, the heat exchange medium flow passage is defined by the first spacer member and the second spacer member, and the ambient air flow passage is defined by two adjacent spacer member groups.

Further, the first spacer member and the second spacer member are integrally formed, or the spacer member group further includes a connecting member for connecting the first spacer member and the second spacer member, or the spacer member group further includes a welding material for connecting the first spacer member and the second spacer member.

Further, the first spacer member and the second spacer member are plate-shaped.

Further, the spacer member group is a hollow plate, and the heat exchange medium flow passage is defined by a hollow structure of the hollow plate.

Further, the distance between two adjacent hollow plates is 10-80 mm.

Further, the plurality of hollow plates are arranged in parallel in the cross-sectional direction.

Further, the hollow plate has a sinusoidal wave-shaped cross section.

Further, the wall surface of the hollow plate extends in a straight line, a broken line, a curved line, or an arc shape in a direction perpendicular to the sine wave-shaped cross section.

Further, the sine waveform is a sine wave shape including half or more wavelengths.

Further, the hollow plate has an extension at one end thereof adjacent to the ambient air flow inlet and at the other end corresponding thereto, respectively.

Further, the extension is a solid structure.

Further, the number of the partition members is plural, the partition members are hollow tubes, the ambient air flow passage is defined by the outer walls of the adjacent two partition members, and the heat exchange medium flow passage is defined by the inner walls of the partition members.

Further, the wrap-around heat exchanger includes one or more spacer component assemblies, each spacer component assembly including a plurality of spacer components.

Further, the distance between two adjacent spacer members is 10 to 80mm.

Further, the plurality of spacer members are arranged in an aligned or staggered manner in the cross-sectional direction.

Further, a plurality of spacer member assemblies are connected in series or parallel.

Further, the cross section of the spacer member is a circular-like closed curve.

Further, the wall surface of the spacer member extends in a straight line, a broken line, a curved shape in a direction perpendicular to the cross section of the quasi-circular closed-shape curve.

Further, buffer water tanks are arranged at two ends of the surrounding type heat exchanger, and the buffer water tanks can contain 50-200L of circulating water. Preferably, the circulating water amount is set according to the number of the surrounding heat exchangers.

The invention also provides a method for removing dust, mist and white smoke, which is characterized by comprising the following steps:

(1) Providing a dedusting and demisting device and a plurality of surrounding heat exchangers;

(2) The dedusting and demisting device is arranged in the desulfurization absorption tower and/or the clean flue gas flue, the plurality of surrounding heat exchangers are arranged to surround the outside of the desulfurization absorption tower and/or the clean flue gas flue, and the dedusting and demisting device and the plurality of surrounding heat exchangers;

(3) The heat exchange medium exchanges heat with the flue gas in the dedusting and demisting device to raise the temperature;

(4) The warmed heat exchange medium flows from the dedusting and demisting device to the surrounding heat exchangers and self-circulates in the surrounding heat exchangers to exchange heat with ambient air to cool;

(5) The cooled heat exchange medium flows from the surrounding heat exchanger to the dedusting and demisting device, so that circulation is formed.

Compared with the prior art, the invention has the following beneficial effects:

1. the dust removing, mist removing and whitening integrated system can perfectly combine the existing environment-friendly requirement of 'whitening' with the environment-friendly requirement of ultralow emission, and the efficient dust removing and defogging device is used for condensing smoke in 'whitening', so that the effect of removing wet smoke mist drops and dust is achieved.

2. The dust removing, mist removing and white eliminating integrated system has small investment, and the high-efficiency dust removing and mist removing device is combined with white eliminating, so that compared with the original independently arranged multi-layer mist eliminator device and independently arranged in-tower heat exchange system, the total investment is saved by more than 50%.

3. The operation energy consumption is low, and the national energy conservation and emission reduction development strategy is met.

4. The surrounding type heat exchanger is made of corrosion-resistant plastic optimally, so that the reliability is high, and the corrosion phenomenon is avoided.

5. Reasonable and even arrangement, suitability for flushing and purging and cleaning, and blockage and scaling phenomena are avoided.

The conception, specific structure, and technical effects of the present invention will be further described with reference to the accompanying drawings to fully understand the objects, features, and effects of the present invention.

Drawings

FIG. 1 is a schematic diagram of an integrated dust and mist and white smoke removal system according to a preferred embodiment of the present invention;

FIG. 2 is a schematic diagram of the operation of a heat exchange medium flow between a desulfurization absorber and a surrounding heat exchanger in accordance with a preferred embodiment of the present invention;

FIG. 3 is a schematic diagram of the operation of a heat exchange medium flow between a desulfurization absorber and a surrounding heat exchanger in accordance with a preferred embodiment of the present invention;

FIG. 4 is a cross-sectional view of a hollow tube in accordance with a preferred embodiment of the present invention;

FIG. 5 is a cross-sectional view of a finned hollow tube in accordance with a preferred embodiment of the present invention;

FIG. 6 is a cross-sectional view of a straight hollow tube along the flow direction of a heat exchange medium according to a preferred embodiment of the present invention;

FIG. 7 is a cross-sectional view of a zigzag hollow tube along the flow direction of a heat exchange medium according to a preferred embodiment of the present invention;

FIG. 8 is a cross-sectional view of a curved hollow tube along the flow direction of a heat exchange medium according to a preferred embodiment of the present invention;

FIG. 9 is a cross-sectional view of a circular arc type hollow tube according to a preferred embodiment of the present invention along the flow direction of a heat exchange medium;

FIG. 10 is a cross-sectional view of a plurality of hollow tubes aligned in accordance with a preferred embodiment of the present invention;

FIG. 11 is a cross-sectional view of a staggered arrangement of a plurality of hollow tubes in accordance with a preferred embodiment of the present invention;

FIG. 12 is a cross-sectional view of a straight hollow plate of a preferred embodiment of the present invention along the flow direction of a heat exchange medium;

FIG. 13 is a cross-sectional view of a sinusoidal wave hollow plate along the flow direction of a heat exchange medium according to a preferred embodiment of the present invention;

FIG. 14 is a cross-sectional view of a zigzag hollow plate along the flow direction of a heat exchange medium according to a preferred embodiment of the present invention;

FIG. 15 is a cross-sectional view of a plurality of hollow plates arranged in parallel in accordance with a preferred embodiment of the present invention;

FIG. 16 is a flow schematic of the cool medium ambient air of a preferred embodiment of the present invention;

FIG. 17 is a schematic diagram of an integrated dust and mist and white smoke removal system according to a preferred embodiment of the present invention;

FIG. 18 is a flow schematic of a heat exchange medium flow between a clean flue gas duct and a surrounding heat exchanger in accordance with a preferred embodiment of the present invention;

Fig. 19 is a schematic structural view of an integrated dust and mist and white smoke removing system according to a preferred embodiment of the present invention.

Detailed Description

The following description of the preferred embodiments of the present invention refers to the accompanying drawings, which make the technical contents thereof more clear and easy to understand. The present invention may be embodied in many different forms of embodiments and the scope of the present invention is not limited to only the embodiments described herein.

In the drawings, like structural elements are referred to by like reference numerals and components having similar structure or function are referred to by like reference numerals. The dimensions and thickness of each component shown in the drawings are arbitrarily shown, and the present invention is not limited to the dimensions and thickness of each component. The thickness of the components is exaggerated in some places in the drawings for clarity of illustration.

Example 1

The dedusting and demisting device 11 in the embodiment is arranged in the desulfurization absorption tower 19, the surrounding type heat exchanger is arranged outside the desulfurization absorption tower 19, and heat exchange medium circulates between the surrounding type heat exchanger and the dedusting and demisting device 11. The smoke concentration of the tail smoke of the boiler enters the desulfurization absorption tower 19 at the concentration of less than or equal to 20mg/Nm3 after passing through the electric dust collector. 4-5 spraying layers are arranged in the desulfurization absorption tower 19, the flue gas is formed into saturated wet flue gas after passing through the spraying layers, the saturated wet flue gas is cooled after passing through the dedusting and demisting device 11, so that dust and/or fog are separated out, and the saturated wet flue gas is changed into unsaturated clean flue gas, so that the generation of white smoke is reduced. Arrow 100 represents the direction of flue gas flow.

As shown in fig. 1 and 2, the circumferential heat exchanger in this embodiment is provided with two. The first circulating heat exchanger 121 is disposed at a first side outside the desulfurization absorbing tower 19, and the second circulating heat exchanger 122 is disposed at a second side outside the desulfurization absorbing tower 19 with respect to the first circulating heat exchanger 121. The first surrounding type heat exchanger 121 supplies the cooled heat exchange medium to the dedusting and demisting device 11 in the desulfurizing absorption tower 19, and the cooled heat exchange medium exchanges heat with saturated wet flue gas passing through the dedusting and demisting device 11, so that the saturated wet flue gas is cooled to separate out a large amount of water vapor, the generated water vapor automatically searches residual tiny fog drops and tiny dust in the flue gas to serve as condensation nuclei, the tiny fog drops and tiny dust absorb a large amount of water vapor and grow up, the flue gas is condensed, and the effect of whitening can be achieved, and meanwhile, the effect of removing the fog drops and dust of the wet flue gas is achieved. Meanwhile, the heat exchange medium absorbs heat and then heats up, the warmed heat exchange medium is output to the second surrounding type heat exchanger 122 through the dust and mist removing device 11, the warmed heat exchange medium sequentially flows through the second surrounding type heat exchanger 122 and the first surrounding type heat exchanger 121 and exchanges heat with an ambient air cold source in a dividing wall mode to cool down, the cooled heat exchange medium is supplied into the dust and mist removing device 11 through the first surrounding type heat exchanger 121 again, circulation is formed, and the heat exchange medium self-circulates in the surrounding type heat exchanger to cool down. Arrow 200 indicates the direction of heat exchange medium flow and arrow 300 indicates the direction of ambient air flow.

In other embodiments, as shown in fig. 3, a plurality of circulating heat exchangers are provided, specifically, a plurality of circulating heat exchangers are uniformly distributed around the desulfurization absorption tower 19, the primary circulating heat exchanger 124 supplies a cooled heat exchange medium to the dedusting and demisting device 11 in the desulfurization absorption tower 19, the cooled heat exchange medium exchanges heat with saturated wet flue gas passing through the dedusting and demisting device 11 to cool the saturated wet flue gas, at the same time, the warmed heat exchange medium absorbs heat and then warms up, the warmed heat exchange medium is output to the secondary circulating heat exchanger 123 through the dedusting and demisting device 11, and the heat exchange medium in the secondary circulating heat exchanger 123 returns to the primary circulating heat exchanger 124 after being cooled by the tertiary, quaternary or even multi-stage circulating heat exchanger, so that circulation is formed, and the heat exchange medium self-circulates in the multi-stage circulating heat exchanger to cool down. Arrow 200 indicates the direction of heat exchange medium flow and arrow 300 indicates the direction of ambient air flow.

The circumferential heat exchanger in this embodiment comprises a heat exchange medium flow channel 1212, an ambient air flow channel and a spacing member for spacing the heat exchange medium flow channel 1212 and the ambient air flow channel and for exchanging heat between the heat exchange medium flow channel 1212 and the ambient air flow channel, the spacing member having a contact surface for exchanging heat with ambient air. The heat exchange medium is configured to flow in the heat exchange medium flow channel 1212, and in this embodiment, the heat exchange medium is water, and in other embodiments, oil may be used.

In this embodiment, the two ends of the surrounding heat exchanger are respectively provided with an inlet water tank and an outlet water tank, both of which are communicated with the hollow plates or the hollow tubes in the surrounding heat exchanger, and the heat exchange medium enters the surrounding heat exchanger through the inlet water tank and is cooled therein, and is then discharged from the outlet water tank to enter the next surrounding heat exchanger. The inlet water tank and the outlet water tank contain 50-200L of circulating water. Preferably, the circulating water amount is set according to the number of the surrounding heat exchangers.

In this embodiment, the number of the spacer members is plural, the spacer members are hollow tubes 1211, the cross section of the hollow tubes 1211 is a circular-like closed curve, the hollow tubes 1211 have smooth outer walls (see fig. 4), and in other embodiments, fins are arranged on the outer walls of the hollow tubes 1211 (see fig. 5). The ambient air flow channel is defined by the outer walls of adjacent hollow tubes 1211, the heat exchange medium flow channel 1212 is defined by the inner walls of the hollow tubes 1211, one end of the hollow tubes 1211 is a flow inlet of the heat exchange medium, the other end of the hollow tubes 1211 is a flow outlet of the heat exchange medium, and the flow inlet and the flow outlet of the heat exchange medium can be arranged on the hollow tubes 1211 as required. Preferably, the ambient air flow channel is a venturi flow channel formed between the outer walls of adjacent hollow tubes 1211. In other embodiments, the hollow tube 1211 may also be a concentric tube, with the ambient air flow channel being defined by the interlayer between the inner tube and the outer tube of the concentric tube and the outer wall of the adjacent concentric tube. The wall surface of the hollow tube 1211 extends in a straight line (see fig. 6), a broken line (see fig. 7), a curved line (see fig. 8), or a circular arc shape (see fig. 9) in a direction perpendicular to the sinusoidal waveform section. The distance between two adjacent hollow tubes 1211 is 10 to 80mm, preferably 40mm. The plurality of hollow tubes 1211 constitutes one or more repeating hollow tube assemblies, and the number of hollow tubes 1211 in each hollow tube assembly is preferably 4 to 200. The hollow pipe assemblies are connected in series or in parallel. The plurality of hollow tubes 1211 are arranged in alignment (see fig. 10) or offset (see fig. 11) in the cross-sectional direction.

In other embodiments, the number of spacer members is a plurality and a plurality of repeating sets of spacer members are formed. The spacer member may also take the form of a plate, preferably having a rectilinear (see fig. 12), sinusoidal (see fig. 13) and a bent (see fig. 14) cross-section. As shown in fig. 15, the spacer member group includes a first spacer member and a second spacer member, the heat exchange medium flow passage 1212 is defined by the first spacer member and the second spacer member, and the ambient air flow passage is defined by two adjacent spacer member groups. The first spacer member and the second spacer member are integrally formed, or the spacer member group further comprises a connecting member for connecting the first spacer member and the second spacer member, or the spacer member group further comprises a welding material for connecting the first spacer member and the second spacer member. Preferably, the spacer member assembly is a hollow plate and the heat exchange medium flow passage 1212 is defined by the hollow structure of the hollow plate. The spacing between two adjacent hollow plates is 10-80 mm, preferably 40mm. The hollow plates are connected in series or in parallel. The plurality of hollow plates are arranged in parallel in the vertical direction.

Preferably, the hollow plate has a sinusoidal wave-shaped cross section. Wherein the sine wave form is a sine wave form comprising half or more wavelengths. Preferably, the sine wave is in the shape of a sine wave comprising 1.0 to 2.5 wavelengths. The wall surface of the hollow plate extends in a straight line, a fold line, a curve or an arc shape in a direction perpendicular to the sine wave-shaped section.

Preferably, the hollow plate has a bent section, the bent section comprising 1 to 10 folds. The wall surface of the hollow plate extends in a straight line, a broken line, a curve or an arc shape in a direction perpendicular to the bent section.

Preferably, the hollow plate has a straight-line cross section, and the wall surface of the hollow plate extends in a straight line, a fold line, a curve, or an arc shape in a direction perpendicular to the bent cross section.

As shown in fig. 12-15, the hollow plate has an extension 17 at one end thereof adjacent to the ambient air flow inlet and at the other end corresponding thereto, respectively. The extension 17 is of solid construction.

In this embodiment, the surrounding heat exchanger is provided with a descaling device, which is a flushing pipe provided with a nozzle or a descaling device provided with a brush.

The dust and mist removing device 11 of the present embodiment is a condensation dust and mist removing device including a cooling medium flow passage, a flue gas flow passage, and a partition member for partitioning the cooling medium flow passage and the flue gas flow passage and for exchanging energy between the cooling medium flow passage and the flue gas flow passage, the partition member having a flue gas contact surface for collecting dust and/or mist in flue gas. The number of the spacing parts is plural, and a plurality of repeated spacing part groups are formed, each spacing part group comprises a third spacing part and a fourth spacing part, the cooling medium flow channel is defined by the third spacing part and the fourth spacing part, and the flue gas flow channel is defined by two adjacent spacing part groups. Specifically, the third spacer member and the third spacer member are plate-shaped. The spacer member group is preferably a hollow plate, and the cooling flow passage is defined by a hollow structure of the hollow plate. The hollow plate has a sinusoidal wave-shaped cross section. The wall surface of the hollow plate extends in a straight line, a fold line, a curve or an arc shape in a direction perpendicular to the sine wave-shaped section. The hollow plate is provided with one or more hook parts; the hooks are located at the peaks and/or troughs of the sinusoidal waveform. The structure of the hollow plate-type spacer member group in the condensation dust removal demister of the present embodiment can be referred to the structure of the hollow plate-type spacer member group in the heat exchange device described above.

In other embodiments, the spacer members in the condensing dust collector mist eliminator are hollow tubes, the flue gas flow passage being defined by outer walls of the plurality of spacer members, and the cooling medium flow passage being defined by inner walls of the spacer members. For the specific structure, reference may be made to the structure of the hollow tube 1211 type spacer member in the above-described surrounding type heat exchanger.

In order to further reduce the smoke content, a two-stage or multi-stage condensation dedusting demister can be adopted, so that the smoke content in the smoke is less than or equal to 5mg/Nm3 or even lower.

In other embodiments, the flue gas mist droplet preseparator 13 is used in combination with a condensing dust and mist eliminator, the flue gas mist droplet preseparator 13 being mounted upstream of the condensing dust and mist eliminator in the direction of flue gas flow. Preferably, the flue gas mist droplet preseparator 13 is a tube mist eliminator and/or a roof-type mist eliminator. Specifically, as shown in fig. 1, the tail flue gas of the boiler enters the desulfurization absorption tower 19, passes through the flue gas mist droplet preseparator 13 and the condensation dust removal demister in sequence for dust removal and/or demisting, and finally the obtained clean flue gas is discharged from a flue opening. The specific structure of the smoke mist preseparator 13 has been described in the prior application CN105983287 a.

In other embodiments, the dust and mist removal and white smoke removal integrated system further comprises a smoke temperature reduction device 15, a smoke temperature rising device 16 and a circulating medium control device and a flushing and/purging device 14. The flue gas cooling device 15 is arranged in the raw flue gas flue, more specifically, the flue gas cooling device 15 is arranged in front of or behind the electric dust removal raw flue gas section, and preferably, is arranged in behind the electric dust removal raw flue gas section. The flue gas temperature increasing device 16 is arranged in the desulfurization absorption tower 19 and/or the clean flue gas flue 18. The flushing and/or purging device 14 is arranged upstream and/or downstream of the flue gas temperature reducing means 15 and the flue gas temperature increasing means 16 to ensure a clean operation of the heat exchange means. Fig. 1 shows that a flushing and/or purging device 14 is arranged downstream of the flue gas cooling device 15 in the raw flue gas stack 100. At the outlet section of the desulfurization absorption tower 19, as shown in fig. 1, a flushing and/or purging device 14 is provided downstream of the flue gas temperature increasing device 16, and in the clean flue gas duct 18, a flushing and/or purging device 14 is provided downstream of the flue gas temperature increasing device 16. The tail flue gas of the boiler enters the original flue gas flue at the concentration of less than or equal to 20mg/Nm3 after passing through the electric dust remover, and in the original flue gas flue, the circulating medium conveyed by the circulating medium control equipment exchanges heat with the original flue gas in the flue gas cooling device 15, so that the original flue gas is cooled, and meanwhile, the circulating medium is heated.

The heated circulating medium is conveyed to the desulfurization absorption tower 19 and/or the flue gas temperature rising device 16 in the clean flue gas flue 18 through a circulating medium control device. The warmed heat exchange medium conveyed from the flue gas cooling device 15 through the circulating medium control equipment exchanges heat with clean flue gas in the flue gas warming device 16, so that the clean flue gas is warmed, meanwhile, the circulating medium is cooled, and the cooled heat exchange medium is conveyed to the flue gas cooling device 15 through the heat exchange medium control equipment, so that circulation is formed. Preferably, the flue gas temperature rising device 16 is arranged in both the desulfurization absorption tower 19 and the clean flue gas flue 18. Specifically, as shown in fig. 1, the tail flue gas of the boiler enters the original flue and is cooled by the flue gas cooling device 15, the cooled flue gas is sprayed by 4-5 layers of spraying layers to form saturated wet flue gas, the saturated wet flue gas is further subjected to a flue gas droplet preseparator and/or a condensation dust removal demister, at the moment, dust and/or mist in the saturated wet flue gas are separated out and settled into cooled unsaturated clean flue gas, and the unsaturated clean flue gas is heated by the flue gas heating device 16, so that the chimney emission condensation phenomenon is reduced, and the white flue gas is reduced.

In order to improve the effect of "white smoke elimination", the smoke temperature reducing device 15 and/or the smoke temperature increasing device 16 are provided with one or more stages, preferably, as shown in fig. 1, in the smoke temperature reducing device 15 and/or the smoke temperature increasing device 16 of the multiple stages, circulating medium flows from the first stage to the last stage, the smoke temperature reducing device 15 and/or the smoke temperature increasing device 16 of the first stage is arranged at the downstream of smoke, and the smoke temperature reducing device 15 and/or the smoke temperature increasing device 16 of the last stage is arranged at the upstream of smoke. This arrangement allows the hottest heat exchange medium to be at a higher temperature flue gas than the colder heat exchange medium to be at a lower temperature flue gas to ensure full heat utilization.

In other embodiments, as shown in fig. 16, a fan 20 is used to replace a surrounding heat exchanger, the fan 20 is arranged at a first side outside the desulfurization absorption tower 19, and cool medium ambient air is continuously blown into the dedusting and demisting device 11, and heat exchange is performed between the cool medium ambient air and saturated wet flue gas so as to cool the saturated wet flue gas and heat the cool medium ambient air, and the heated cool medium ambient air is discharged from the other side of the desulfurization absorption tower 19 opposite to the fan.

Example 2

As shown in fig. 17, the dedusting and demisting apparatus 21 in this embodiment is installed in the clean flue gas duct 28, the surrounding heat exchanger is installed outside the clean flue gas duct 28, and the heat exchange medium circulates between the surrounding heat exchanger and the dedusting and demisting apparatus 21. The clean flue gas refers to the flue gas which is dedusted and/or fogged by the dedusting and defogging device 21, and a clean flue gas flue 28 is positioned at the outlet of the desulfurizing tower so as to enable the clean flue gas to flow. The smoke concentration of the tail smoke of the boiler enters the desulfurization absorption tower 19 at the concentration of less than or equal to 20mg/Nm < 3 >, 4-5 layers of spraying layers are arranged in the desulfurization absorption tower 19, the smoke forms saturated wet smoke after passing through the spraying layers, and the saturated wet smoke is cooled after passing through the dedusting and demisting device 21 in the clean smoke flue 28 so as to separate out dust and/or fog, and becomes unsaturated clean smoke so as to reduce the generation of white smoke. Arrow 100 represents the direction of flue gas flow.

The designs of this embodiment include the structure of heat exchange medium cooling and the structure of other devices of the dust and mist removal and white smoke removal integrated system, see embodiment 1.

Still further, if the space of the clean flue gas duct 28 is limited or the product separation performance is improved, the condensing dust and mist eliminator in the clean flue gas duct 28 may be designed in a V-shape, i.e., a roof-type design. The direction of the V-shaped peak is the same as or opposite to the direction of the smoke flow, and is preferably selected to be opposite to the direction of the smoke flow so as to improve the structural stability of the product.

In other embodiments, the fan 20 is used to replace the surrounding heat exchanger, the fan 20 is arranged on the first side outside the clean flue gas flue 28, and cool medium ambient air is continuously blown into the dedusting and demisting device 21, and heat exchange is performed between the cool medium ambient air and saturated wet flue gas so as to cool the saturated wet flue gas and heat the cool medium ambient air, and the heated cool medium ambient air is discharged from the other side of the clean flue gas flue 28 opposite to the fan.

Example 3

As shown in fig. 19, the dust and mist removing device 31 in this embodiment is installed inside the desulfurization absorption tower 39 and the clean flue gas duct 38, and the surrounding heat exchanger is installed outside the desulfurization absorption tower 39 and the clean flue gas duct 38. The smoke concentration of the tail smoke of the boiler enters the desulfurization absorption tower 39 at the concentration of less than or equal to 20mg/Nm < 3 >, 4-5 layers of spraying layers are arranged in the desulfurization absorption tower 39, the smoke forms saturated wet smoke after passing through the spraying layers, and the saturated wet smoke is cooled after passing through the desulfurization absorption tower 39 and the dedusting and demisting device 31 in the clean smoke flue 38 so as to separate out dust and/or fog, and becomes unsaturated clean smoke so as to reduce the generation of white smoke. Arrow 100 represents the direction of flue gas flow.

The designs of this embodiment include the structure of the surrounding heat exchanger and other devices of the dust and mist and white smoke removal integrated system, see embodiment 1.

Still further, if the space of the clean flue gas duct 38 is limited or the product separation performance is improved, the condensing dust and mist eliminator in the clean flue gas duct 38 may be designed in a V-shape, i.e., a roof-type design. The direction of the V-shaped peak is the same as or opposite to the direction of the smoke flow, and is preferably selected to be opposite to the direction of the smoke flow so as to improve the structural stability of the product.

In other embodiments, the fan 20 is used in place of the surrounding heat exchanger, the fan 20 is disposed on a first side of the clean flue gas duct 38, and the cool medium ambient air is continuously blown into the dust and mist removing device 31, and the cool medium ambient air exchanges heat with the saturated wet flue gas to cool the saturated wet flue gas and raise the temperature of the cool medium ambient air, and the heated cool medium ambient air exits from the other side of the clean flue gas duct 38 opposite to the fan.

The foregoing describes in detail preferred embodiments of the present invention. It should be understood that numerous modifications and variations can be made in accordance with the concepts of the invention without requiring creative effort by one of ordinary skill in the art. Therefore, all technical solutions which can be obtained by logic analysis, reasoning or limited experiments based on the prior art by the person skilled in the art according to the inventive concept shall be within the scope of protection defined by the claims.

Claims (21)

1. The integrated system for dedusting, demisting and whitening is characterized by comprising a dedusting and demisting device and a plurality of surrounding heat exchangers, wherein the dedusting and demisting device is arranged in a desulfurization absorption tower and/or a clean flue gas flue, the surrounding heat exchangers are arranged to surround outside the desulfurization absorption tower and/or the clean flue gas flue, the surrounding heat exchangers are arranged in series and/or in parallel, the surrounding heat exchangers are communicated with the dedusting and demisting device, so that a heat exchange medium flows in the surrounding heat exchangers and exchanges heat with ambient air to cool, the cooled heat exchange medium enters the dedusting and demisting device and exchanges heat with saturated wet flue gas to whiten the flue gas, and the surrounding heat exchanger comprises a heat exchange medium flow channel, an ambient air flow channel and a spacing part for spacing the heat exchange medium flow channel and the ambient air flow channel and for exchanging heat between the heat exchange medium flow channel and the ambient air flow channel, and the spacing part is provided with a contact surface for exchanging heat with the ambient air.

2. The dust and mist removal and white smoke removal integrated system of claim 1, wherein said plurality of spacer members is a plurality and forms a plurality of repeating spacer member sets, said spacer member sets including a first spacer member and a second spacer member, said heat exchange medium flow passage being defined by said first spacer member and said second spacer member, said ambient air flow passage being defined by adjacent two of said spacer member sets.

3. The dust and mist removal and white smoke removal integrated system of claim 2, wherein the first spacer member and the second spacer member are integrally formed, or the spacer member group further comprises a connector for connecting the first spacer member and the second spacer member, or the spacer member group further comprises a welding material for connecting the first spacer member and the second spacer member.

4. The dust and mist removal and white smoke removal integrated system of claim 3, wherein said first spacer member and said second spacer member are plate-shaped.

5. The dust and mist removal and white smoke removal integrated system of claim 4, wherein said set of spacer members is a hollow plate, said heat exchange medium flow passage being defined by a hollow structure of said hollow plate.

6. The dust and mist removing and white smoke removing integrated system of claim 5, wherein the distance between two adjacent hollow plates is 10-80 mm.

7. The dust and mist removal and white smoke removal integrated system of claim 5, wherein a plurality of said hollow plates are arranged in parallel in a cross-sectional direction.

8. The dust and mist removal and white smoke removal integrated system of claim 5, wherein said hollow plate has a sinusoidal wave shaped cross section.

9. The dust and mist removal and white smoke removal integrated system of claim 8, wherein the wall surface of the hollow plate extends in a straight line, a broken line, a curve or a circular arc shape in a direction perpendicular to the sinusoidal waveform section.

10. The dust and mist removal and white smoke removal integrated system of claim 9, wherein said sinusoidal waveform is a sinusoidal waveform comprising half or more wavelengths.

11. The dust and mist and white smoke removal integrated system of any one of claims 5 to 10, wherein the hollow plate has an extension at one end thereof adjacent to the ambient air flow inlet and at the other end thereof, respectively.

12. The dust and mist and white smoke removal integrated system of claim 11, wherein said extension is a solid structure.

13. The dust and mist removal and white smoke removal integrated system of claim 1, wherein the number of said spacer members is plural, said spacer members are hollow tubes, said ambient air flow passage is defined by outer walls of adjacent two of said spacer members, and said heat exchange medium flow passage is defined by inner walls of said spacer members.

14. The dust and mist removal and white smoke removal integrated system of claim 13, wherein said surrounding heat exchanger comprises one or more spacer component assemblies, each of said spacer component assemblies comprising a plurality of said spacer components.

15. The dust and mist and white smoke removal integrated system of claim 13, wherein a distance between two adjacent said spacing members is 10-80 mm.

16. The dust and mist removal and white smoke removal integrated system of claim 13, wherein a plurality of said spacer members are arranged in an aligned or staggered manner in a cross-sectional direction.

17. The dust and mist and white smoke removal integrated system of any of claims 13-16, wherein a plurality of said spacer member assemblies are connected in series or parallel.

18. The dust and mist and white smoke removal integrated system of claim 17, wherein said spacer member is circular-like closed curve in cross-section.

19. The dust and mist removal and white smoke removal integrated system of claim 18, wherein the wall surface of the spacer member extends in a straight line, broken line, curved shape in a direction perpendicular to the cross section of the circular-like closed-shaped curve.

20. The integrated system for dedusting, defogging and whitening as recited in claim 1, wherein the two ends of the surrounding heat exchanger are provided with buffer water tanks which can hold 50-200L of circulating water.

21. A method of dedusting, mist and white smoke removal, characterized in that the integrated dedusting, mist and white smoke removal system according to any one of claims 1 to 20 is used, comprising the steps of:

(1) Providing a dedusting and demisting device and a plurality of surrounding heat exchangers;

(2) The dedusting and demisting device is arranged in the desulfurization absorption tower and/or the clean flue gas flue, the plurality of surrounding heat exchangers are arranged to surround the outside of the desulfurization absorption tower and/or the clean flue gas flue, and the dedusting and demisting device is communicated with the plurality of surrounding heat exchangers;

(3) The heat exchange medium exchanges heat with the flue gas in the dedusting and demisting device to raise the temperature;

(4) The warmed heat exchange medium flows from the dedusting and demisting device to the surrounding heat exchangers and self-circulates in a plurality of the surrounding heat exchangers to exchange heat with ambient air so as to cool;

(5) The cooled heat exchange medium flows from the surrounding type heat exchanger to the dedusting and demisting device, so that circulation is formed.