Dust removal device, dust removal system and dust removal method for dust-containing gas of saturated or nearly saturated steam

Abstract

The invention provides a dust removal device, a dust removal system and a dust removal method for dust-containing gas of saturated steam or nearly saturated steam, and relates to the technical field of dust removal, the dust removal device comprises a horizontal centrifugal mixer and a bag-type dust remover; the horizontal centrifugal mixer comprises a horizontally arranged barrel-shaped shell, a dusty gas pipeline and a mixed gas outlet, the dusty gas pipeline and the mixed gas outlet are respectively positioned at two ends of the barrel-shaped shell, the mixed gas outlet, the dusty gas pipeline and the barrel-shaped shell are coaxially arranged, and a gas inlet of the bag-type dust collector is communicated with the mixed gas outlet; a spiral blade is arranged in the barrel-shaped shell, a hot flue gas pipeline is arranged at the end, close to the dusty gas pipeline, of the barrel-shaped shell, and the gas inlet direction of the hot flue gas pipeline is arranged in the tangential direction of the barrel-shaped shell. The technical problems that in the prior art, dust removal of dust-containing gas which is saturated or close to saturated steam can generate condensed water, dust adheres to the surface of a filtering element, the dust removal effect is poor, the filtering element is blocked, and a dust remover loses efficacy are solved.

Description

Technical Field

[0001] The present invention relates to the technical field of dust removal, and in particular to a dust removal device, a dust removal system and a dust removal method for a dust-containing gas of saturated or nearly saturated steam. Background Art

[0002] In the field of pulverized coal pyrolysis, whether it is coal drying or extracting part of the water vapor in the low-temperature section of the pyrolysis kiln of water-containing pulverized coal, a large amount of coal dust is contained in the water vapor. The treatment of this kind of dust often adopts bag filters, spray towers, impact wet dust collectors, wet electrostatic precipitators, water film cyclone dust collectors, Venturi dust collectors or scrubbers, etc.

[0003] When only using a bag filter, when a dust-containing gas of saturated or nearly saturated steam enters a bag filter with a low ambient temperature, when the steam temperature approaches the dew point temperature, a large amount of condensate will be generated, resulting in dust adhering to the surface of the filter element, poor dust cleaning effect, blockage of the filter element, and failure of the dust collector.

[0004] Similar to spray towers, water film cyclone dust collectors, etc., for pulverized coal with a fineness less than 100 microns, especially when the particulate matter is less than 20 microns, it is difficult to dissolve in water, the dust is easy to fly, the environment is harsh, and the difficulty and cost of water treatment make it difficult for enterprises to survive.

[0005] Wet electrostatic precipitators are usually used as "precision" dust collectors supporting other wet dust collectors, and have strict requirements on the dust concentration at the equipment inlet. In addition, they have high energy consumption, complex equipment, high maintenance costs, and are not suitable for hydrophobic dust. Especially when the dust is also conductive, it will cause production and safety accidents due to the internal generation of electric sparks.

[0006] In view of this, the present invention is specifically proposed. Summary of the Invention

[0007] One of the purposes of the present invention is to provide a dust removal device for a dust-containing gas of saturated or nearly saturated steam, so as to solve the technical problem in the prior art that a large amount of condensate is generated during the dust removal of a dust-containing gas of saturated or nearly saturated steam, resulting in dust adhering to the surface of the filter element, poor dust cleaning effect, blockage of the filter element, and failure of the dust collector.

[0008] The second purpose of the present invention is to provide a dust removal system for a dust-containing gas of saturated or nearly saturated steam.

[0009] The third purpose of the present invention is to provide a dust removal method for a dust-containing gas of saturated or nearly saturated steam.

[0010] In order to achieve the above purposes of the present invention, the following technical solutions are specifically adopted:

[0011] In a first aspect, the present invention provides a dust removal device for a dust-containing gas of saturated or nearly saturated steam, comprising a horizontal centrifugal mixer and a bag filter;

[0012] The horizontal centrifugal mixer includes a barrel-shaped housing arranged horizontally, a dust-containing gas pipeline and a mixed gas outlet respectively located at both ends of the barrel-shaped housing. The mixed gas outlet, the dust-containing gas pipeline and the barrel-shaped housing are coaxially arranged. The air inlet of the bag filter is communicated with the mixed gas outlet;

[0013] A spiral blade is provided inside the barrel-shaped housing. A hot flue gas pipeline is provided at one end of the barrel-shaped housing close to the dust-containing gas pipeline, and the inlet direction of the hot flue gas pipeline is arranged along the tangential direction of the barrel-shaped housing; A dust hopper I for collecting dust removal ash is provided at one end of the lower part of the barrel-shaped housing close to the mixed gas outlet.

[0014] Further, a perforated plate is provided inside the bag filter. The perforated plate divides the bag filter into an upper box body and a middle box body. Filter units are correspondingly provided on the perforated plate and are located inside the middle box body. The air inlet is located on the middle box body;

[0015] Preferably, an upward air guiding channel is provided inside the middle box body, and the air guiding channel is communicated with the air inlet;

[0016] Preferably, a dust hopper II for collecting dust removal ash is provided below the middle box body;

[0017] Preferably, a gas outlet is provided on the upper box body;

[0018] Preferably, an air backwashing unit is provided at the top of the filter unit;

[0019] Preferably, the filtering material of the filter unit is any one of PTFE, PPS or acrylic.

[0020] Further, the air guiding channel includes a flat plate and a vertical plate, and the vertical plate, the flat plate and the middle box body cooperate with each other to form the air guiding channel;

[0021] Preferably, the vertical distance between the plane where the top end of the vertical plate is located and the lower end surface of the perforated plate is 0.3 - 1 m;

[0022] Preferably, a plurality of flow dividing plates are provided inside the air guiding channel, and the plurality of flow dividing plates cooperate with the air guiding channel to disperse the gas in different directions;

[0023] Preferably, the bottom of the flow dividing plate is connected to the flat plate, and the top surface height of the flow dividing plate is the same as the top surface height of the air inlet;

[0024] Preferably, the plurality of flow dividing plates are distributed in a fan shape along the surface of the flat plate.

[0025] Further, the air guiding channel is a pipeline structure;

[0026] Preferably, the vertical distance between the plane where the air outlet end of the pipeline structure is located and the lower end face of the flower plate is 1 / 3 to 1 times the diameter of the pipeline structure;

[0027] Preferably, the pipeline structure includes a vertical straight pipe and an elbow. One end of the elbow is communicated with the air inlet, and the other end of the elbow is communicated with the bottom of the vertical straight pipe.

[0028] Further, annular shells I and II are respectively arranged at both ends of the barrel-shaped outer shell. An annular shell I is provided at the mixed gas outlet as the mixed gas outlet, and the annular shell II is communicated with the dust-containing gas pipeline;

[0029] Preferably, the mixed gas outlet is communicated with the air inlet through Pipeline I.

[0030] In a second aspect, the present invention provides a dust removal system for a dust-containing gas of saturated or nearly saturated steam, including the above-mentioned dust removal device, an induced draft fan, and a dust recovery device. The induced draft fan is communicated with the air outlet of the bag filter, and the dust recovery device is located below the dust removal device.

[0031] Further, the dust recovery device includes a finished product bin, and the finished product bin is respectively communicated with Hopper I and Hopper II;

[0032] Preferably, the dust recovery device further includes an enclosed belt conveyor communicated with the finished product bin;

[0033] Preferably, the finished product bin is communicated with Hopper I through a screw discharger or a disc air lock discharger valve;

[0034] Preferably, the finished product bin is communicated with Hopper II through a screw discharger or a disc air lock discharger valve.

[0035] Further, the induced draft fan is communicated with the gas outlet through Pipeline II.

[0036] In a third aspect, the present invention provides a dust removal method for a dust-containing gas of saturated or nearly saturated steam, including preheating a horizontal centrifugal mixer by introducing hot flue gas through a hot flue gas pipeline, then introducing the dust-containing gas through a dust-containing gas pipeline, mixing the dust-containing gas and the hot flue gas through the horizontal centrifugal mixer to obtain a mixed gas, transporting the mixed gas to a bag filter for dust removal, and simultaneously recovering the dust collected by the horizontal centrifugal mixer and the bag filter.

[0037] Further, the temperature of the preheating is 130 to 160 °C;

[0038] Preferably, the temperature of the mixed gas is 110 to 180 °C;

[0039] Preferably, the moisture content of the dedusted ash is 5-16%;

[0040] Preferably, the temperature of the hot flue gas is 150-300 °C, preferably 180-260 °C;

[0041] Preferably, the hot flue gas is industrial flue gas.

[0042] The dust removal device for a dust-containing gas of saturated or nearly saturated steam provided by the present invention can transport the hot flue gas to the inner cavity of the horizontal centrifugal mixer along the tangential direction of the barrel-shaped housing through the hot flue gas pipeline, which is conducive to uniform distribution to achieve the purpose of uniform preheating. At the same time, it is mixed and heated with the dust-containing gas input through the dust-containing gas pipeline along the rotation direction to form a dust-containing dry gas, and the dust-containing dry gas passes through the bag filter to filter out the dust in the gas. It solves the technical problems in the prior art that a large amount of condensed water is generated during the dust removal of the dust-containing gas of saturated or nearly saturated steam, resulting in dust adhering to the surface of the filter element, poor dust cleaning effect, blockage of the filter element, and failure of the dust collector. It further eliminates the water treatment pressure brought by dust removal methods such as spraying, and has significant advantages compared with any other dust removal scheme.

[0043] On the other hand, the provided dust removal method can avoid condensation due to temperature reduction after the dust-containing gas enters by preheating, heat the dust-containing gas with the hot flue gas to obtain a dust-containing dry gas, ensure the continuous and stable operation of the filtration, avoid the problem of poor falling of the dedusted ash due to too high moisture content of the dedusted ash, and especially can avoid the problems of dust sticking to the bag and filtration failure. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the drawings required to be used in the description of the specific embodiments or the prior art. Obviously, the following drawings are some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0045] Figure 1 Structural schematic of a dust removal device and a dust removal system for a dust-containing gas of saturated or nearly saturated steam provided by the present invention Figure 1 ;

[0046] Figure 2 Structural schematic diagram of the air guiding channel in the bag filter provided by the present invention;

[0047] Figure 3 Structural schematic diagram of the air guiding channels in multiple juxtaposed bag filters provided by the present invention;

[0048] Figure 4Schematic structure of a dust removal device and a dust removal system for a dust-containing gas with saturated or nearly saturated steam provided by the present invention Figure 2 。

[0049] Icon: 1 - Dust-containing gas pipeline; 2 - Hot flue gas pipeline; 3 - Horizontal centrifugal mixer; 31 - Barrel-shaped housing; 32 - Spiral blade; 33 - First annular housing; 34 - Second annular housing; 35 - First ash hopper; 4 - First pipeline; 5 - Bag filter; 51 - Upper box body; 52 - Flower plate; 53 - Middle box body; 54 - Air inlet; 55 - Second ash hopper; 56 - Air guide channel; 561 - Flat plate; 562 - Vertical plate; 563 - Shunt plate; 57 - Filter unit; 58 - Gas outlet; 59 - Backwashing unit; 6 - Second pipeline; 7 - Induced draft fan; 81 - Screw discharger; 82 - Disk type airtight discharging valve; 9 - Enclosed belt conveyor; 10 - Finished product bin. Specific embodiments

[0050] Unless otherwise defined herein, scientific and technical terms used in conjunction with the present invention shall have the meanings commonly understood by those of ordinary skill in the art. The meanings and scopes of the terms should be clear. However, in any case of potential ambiguity, the definitions provided herein shall prevail over any dictionary or extrinsic definition. In this application, unless otherwise specified, the use of "or" means "and / or". In addition, the use of the term "including" and other forms is non-restrictive.

[0051] The technical solutions of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0052] On the one hand, the present invention provides a dust removal device for a dust-containing gas with saturated or nearly saturated steam, including a horizontal centrifugal mixer 3 and a bag filter 5;

[0053] The horizontal centrifugal mixer 3 includes a horizontally arranged barrel-shaped housing 31, a dust-containing gas pipeline 1 and a mixed gas outlet respectively located at both ends of the barrel-shaped housing 31. The mixed gas outlet, the dust-containing gas pipeline 1 and the barrel-shaped housing 31 are coaxially arranged. The air inlet 54 of the bag filter 5 is communicated with the mixed gas outlet;

[0054] A spiral blade 32 is arranged in the barrel-shaped housing 31. A hot flue gas pipeline 2 is arranged at one end of the barrel-shaped housing 31 close to the dust-containing gas pipeline 1. The inlet direction of the hot flue gas pipeline 2 is arranged along the tangential direction of the barrel-shaped housing 31; One end of the barrel-shaped housing 31 close to the mixed gas outlet is provided with a first ash hopper 35 for collecting dust removal ash below.

[0055] The hot flue gas pipeline 2 can convey hot flue gas to the inner cavity of the horizontal centrifugal mixer 3 in the tangential direction of the barrel-shaped housing 31, which is conducive to uniform distribution to achieve the purpose of uniform preheating. At the same time, it is mixed and heated with the dust-containing gas input by the dust-containing gas pipeline 1 along the rotation direction to make it into dust-containing dry gas. The dust-containing dry gas passes through the bag filter 5 to filter out the dust in the gas. It solves the technical problem in the prior art that a large amount of condensed water will be generated during the dust removal of dust-containing gas with saturated or nearly saturated steam, resulting in dust adhering to the surface of the filter element, poor dust cleaning effect, blockage of the filter element, and failure of the dust collector. It further eliminates the water treatment pressure brought by dust removal methods such as spraying, and has significant advantages compared with any other dust removal solutions.

[0056] In some specific embodiments, a perforated plate 52 is provided in the bag filter 5. The perforated plate 52 divides the bag filter 5 into an upper box body 51 and a middle box body 53. Corresponding filter units 57 are provided on the perforated plate 52 and are located in the middle box body 53. The air inlet 54 is located on the middle box body 53.

[0057] In some specific embodiments, an upward air guiding channel 56 is provided in the middle box body 53. The air guiding channel 56 is communicated with the air inlet 54.

[0058] The mixed gas is guided to the upper part space of the middle box body 53 through the upward air guiding channel 56 and then turns back downward, which is consistent with the falling direction of the dust in the filter chamber, improving the dust removal efficiency; otherwise, if the gas flows from bottom to top, the air flow direction is opposite to the dust falling direction, and the dust will fall, move up, and be filtered repeatedly under the drive of the air flow, thus affecting the filtering efficiency.

[0059] In some specific embodiments, a second ash hopper 55 for collecting dust removed is provided below the middle box body 53.

[0060] In some specific embodiments, a gas outlet 58 is provided on the upper box body 51. The gas outlet 58 can be located at the top or side of the upper box body 51.

[0061] In some specific embodiments, a backwashing unit 59 is provided at the top of the filter unit 57.

[0062] In some specific embodiments, the material of the filtering material of the filter unit 57 is any one of PTFE, PPS, or acrylic. Optionally, the filtering material includes filter elements or filter bags, preferably filter bags.

[0063] In some specific embodiments, the air guiding channel 56 includes a flat plate 561 and a vertical plate 562, and the vertical plate 562, the flat plate 561 and the middle box body 53 cooperate with each other to form the air guiding channel 56. In some specific embodiments, the vertical distance between the plane where the top end of the vertical plate 562 is located and the lower end surface of the flower plate 52 is 0.3 to 1 m.

[0064] Among them, the vertical distance between the plane where the top end of the vertical plate 562 is located and the lower end surface of the flower plate 52 can be, but is not limited to, 0.3 m, 0.4 m, 0.5 m, 0.6 m, 0.7 m, 0.8 m, 0.9 m or 1 m, and can also be any value between 0.3 and 1 m.

[0065] In some specific embodiments, a plurality of flow dividing plates 563 are arranged in the air guiding channel 56, and the plurality of flow dividing plates 563 cooperate with the air guiding channel 56 to disperse the gas in different directions, so that the air flow is evenly distributed inside. In some specific embodiments, the bottom of the flow dividing plate 563 is connected to the flat plate 561, and the top height of the flow dividing plate 563 is consistent with the height of the air inlet 54. In some specific embodiments, the plurality of flow dividing plates 563 are distributed in a fan shape along the surface of the flat plate 561.

[0066] In some specific embodiments, the air guiding channel 56 is a pipe structure; in some specific embodiments, the vertical distance between the plane where the air outlet end of the pipe structure is located and the lower end surface of the flower plate 52 is 1 / 3 to 1 of the diameter of the pipe structure. In some specific embodiments, the pipe structure includes a vertical straight pipe and an elbow, one end of the elbow is communicated with the air inlet 54, and the other end of the elbow is communicated with the bottom of the vertical straight pipe.

[0067] In some specific embodiments, a ring-shaped housing one 33 and a ring-shaped housing two 34 are respectively arranged at both ends of the barrel-shaped housing 31, and the ring-shaped housing one 33 is provided at the mixed gas outlet as the mixed gas outlet, and the ring-shaped housing two 34 is communicated with the dust-containing gas pipeline 1.

[0068] In some specific embodiments, the mixed gas outlet is communicated with the air inlet 54 through a pipeline one 4.

[0069] In order to facilitate the adjustment of the gas flow rate, a cut-off valve and a flow regulating valve are arranged on the hot flue gas pipeline 2. So as to open and close the pipeline and adjust the flue gas flow rate, change the mixing ratio of the flue gas flow rate and the dust-containing gas of saturated or near-saturated steam, so as to adjust the mixed gas to have a suitable temperature, the mixed gas can be in a dry gas state, and at the same time ensure that the dust removal ash has a suitable humidity.

[0070] According to another aspect of the present invention, a dust removal system for dust-containing gas of saturated or nearly saturated steam is also provided, comprising the above-mentioned dust removal device, an induced draft fan 7 and a dust ash recovery device, wherein the induced draft fan 7 is connected to the air outlet of the bag filter 5, and the dust ash recovery device is located below the dust removal device.

[0071] The filtered gas is led out by the induced draft fan 7, and the dust collected by the dust removal equipment is recovered by the dust removal equipment. The system is reliable in operation, has low equipment investment, is environmentally friendly, and has low operating costs.

[0072] In order to reduce the difficulty of dust collection, in some specific embodiments, the dust ash recovery device includes a finished product bin 10, which is respectively connected to the ash hopper 1 35 and the ash hopper 2 55. The dust collected by the dust removal device falls into the finished product bin 10 and is mixed with the finished product material, so that the dust (coal fines) collected by the dust collector is directly mixed with the upgraded coal after pyrolysis to become the finished product material, which greatly reduces the difficulty of dust collection.

[0073] In some specific embodiments, the dust recovery device also includes a closed belt conveyor 9 connected to the finished product silo 10.

[0074] In some specific embodiments, the finished product silo 10 is connected to the ash hopper 1 35 via a screw discharger 81 or a disc-type air-locking discharge valve 82; in some specific embodiments, the finished product silo 10 is connected to the ash hopper 2 55 via a screw discharger 81 or a disc-type air-locking discharge valve 82.

[0075] In some specific embodiments, the induced draft fan 7 is connected to the gas outlet 58 through a pipeline 2 6 .

[0076] According to another aspect of the present invention, a method for removing dust from dust-containing gas of saturated or nearly saturated steam is provided, comprising introducing hot flue gas through a hot flue gas duct 2 to preheat a horizontal centrifugal mixer 3, introducing dust-containing gas through a dust-containing gas duct 1, mixing the dust-containing gas with the hot flue gas through the horizontal centrifugal mixer 3 to obtain a mixed gas, conveying the mixed gas to a bag filter 5 for dust removal, and recovering dust collected by the horizontal centrifugal mixer 3 and the bag filter 5.

[0077] Preheating can prevent condensation of dust-laden gas due to temperature drop after it enters the filter. The hot flue gas can heat the dust-laden gas to obtain dust-laden dry gas, thereby ensuring continuous and stable operation of the filtration. This avoids the problem of dust ash not falling smoothly due to excessive moisture content in the dust ash, and especially prevents dust ash from sticking to the bag and causing filtration failure.

[0078] The flow rate of the hot flue gas can also be adjusted according to the dust-containing gas flow rate of saturated or nearly saturated steam, the temperature of the mixed gas, and the humidity of the dust removal ash, so as to control the temperature of the mixed gas in the bag filter to ensure the inlet temperature. In some specific embodiments, the preheating temperature is 130-160°C; in some specific embodiments, the temperature of the mixed gas is 110-180°C.

[0079] In some specific embodiments, the moisture content of the dust removal ash is 5-16%, which avoids the easy dusting of the dust removal ash when it is too dry.

[0080] In some specific embodiments, the temperature of the hot flue gas is 150-300°C. Among them, the temperature of the hot flue gas can be, but is not limited to, 150°C, 180°C, 200°C, 230°C, 260°C, 280°C or 300°C, and can also be any value between 150-300°C, preferably 180-260°C. Optionally. The hot flue gas is industrial flue gas. Using the waste flue gas in this temperature range to mix and heat up the dust-containing gas of saturated or nearly saturated steam makes the steam in a dry gas state, realizing the utilization of industrial flue gas resources and saving costs at the same time.

[0081] The present invention will be further described below through embodiments. Unless otherwise specified, the materials in the embodiments are prepared according to existing methods or directly purchased from the market.

[0082] The dust-containing gas in the following embodiments is a dust-containing gas containing saturated or nearly saturated steam.

[0083] Example 1

[0084] Combined Figure 1 For illustration, a dust removal device for a dust-containing gas of saturated or nearly saturated steam includes a horizontal centrifugal mixer 3 and a bag filter 5; the horizontal centrifugal mixer 3 includes a horizontal barrel-shaped housing 31, a spiral blade 32 is arranged inside the barrel-shaped housing 31, an annular housing one 33 is arranged at one end of the barrel-shaped housing 31, and a pipeline one 4 is used to connect the inner circle of the annular housing one 11 and the air inlet 54 of the bag filter. An annular housing two 34 is arranged at the other end of the barrel-shaped housing 31, and the inner circle of the annular housing two 34 is connected to the dust-containing gas pipeline 1. A hot flue gas pipeline 2 is arranged at the barrel-shaped housing 31 near the annular housing two 34 and in the tangential direction of the barrel-shaped housing 31 of the horizontal centrifugal mixer, and is communicated with the inner cavity of the horizontal centrifugal mixer 3; a hopper one 35 is arranged at the lower part of the barrel-shaped housing 31 near the annular housing one 33 and is communicated with the inside of the barrel-shaped housing 31.

[0085] The bag filter 5 is provided with an upper box body 51, a middle box body 53, and a second ash hopper 55 from top to bottom. Among them, a perforated plate 52 is arranged between the upper box body 51 and the middle box body 53, and a filter unit 57 is arranged corresponding to the perforated plate 52. An inverse blowing unit 59 is arranged at the top of the filter unit 57. A gas outlet 58 is arranged at the top or side of the upper box body 51 and is connected to an induced draft fan 7. An air inlet 54 arranged on the side of the middle box body 53 is connected to the first annular shell of the horizontal centrifugal mixer 3. The upper end of the second ash hopper 55 is connected to the lower end of the middle box body 53, and a disc type airtight discharging valve 82 is arranged below the second ash hopper 55. The disc type airtight discharging valve 82 has the function of isolating the upper and lower parts of the valve and allowing air to pass through, avoiding the escape of gas in the ash hopper, and at the same time, ensuring smooth discharging.

[0086] In this example, the diameter of the dust-containing gas inlet is DN250, and the diameter of the hot flue gas inlet is DN125; the hot flue gas enters radially and forms a turbulent flow with the axially input dust-containing gas under the spiral guidance, making it easy for the two gases to be mixed evenly, causing the dust-containing gas to be heated up and become dry dust-containing gas. And, under the action of centrifugal force, part of the dust can be removed in advance and enter the first ash hopper, reducing the load on the bag filter.

[0087] A cut-off valve and a flow regulating valve are arranged at the front end where the hot flue gas pipeline 2 enters the centrifugal mixer 3, so as to open and close the pipeline and regulate the flow of the hot flue gas, control the ratio of the flue gas flow to the dust-containing gas, and make the temperature of the mixed gas in the bag filter between 110 and 180 °C, and the humidity of the dust removed is between 5 and 16% in terms of moisture content.

[0088] The bag filter is provided with an upper box body 51, a middle box body 53, and a second ash hopper 55 from top to bottom. Among them, a gas outlet 58 is arranged at the top of the upper box body 51. The upper box body 51 serves as a gas collecting chamber and adopts an integral welded structure, and a maintenance manhole with a sealing structure is arranged on its side; a perforated plate 52 is arranged between the upper box body 51 and the middle box body 53, and a filter unit 57 is arranged corresponding to the perforated plate 52. The filter material of the filter unit 57 adopts PTFE material filter bags with high temperature resistance, acid and alkali resistance, and good hydrophobicity. An inverse blowing unit 59 is arranged at the top of the filter unit 57; an air inlet 54 arranged on the side of the middle box body 53 is connected to the first annular shell of the horizontal centrifugal mixer 33, and a gas guiding channel 56 with an upward gas flow direction is arranged at the position opposite to the air inlet 54. The gas guiding channel 56 is connected to the air inlet 54, and the distance from the top of the gas guiding channel 56 to the lower surface of the perforated plate 52 is 0.6 meters.

[0089] Combined with Figure 2For illustration, the air guiding channel 56 is composed of a vertical plate 562 and a flat plate 561. Among them, the position of the flat plate 561 is lower than the lower edge of the air inlet 54. One end of the flat plate 561 is fixedly connected to the side wall of the middle box body 53 on the air inlet side, and the other end is fixedly connected to the vertical plate 562. The cavity formed by the vertical plate 562, the flat plate 561 and the middle box body 53 is the air guiding channel 56. According to the structure of the bag filter 5, multiple fan-shaped vertical flow dividing plates 563 can be arranged in the air guiding channel 56.

[0090] Example 2

[0091] Combined with Figure 3 For illustration, different from Example 1, there are three bag filters 5 arranged in parallel.

[0092] Example 3

[0093] Combined with Figure 4 For illustration, different from Example 1, the air guiding channel 56 is a pipeline. The pipeline includes an upper vertical straight section and a lower elbow. One end of the elbow is communicated with the straight section, and the other end is communicated with the air inlet 54. The distance from the top of the air guiding channel to the lower surface of the flower plate is 0.6 times the diameter of the air guiding channel. No vertical flow dividing plate is arranged in the air guiding channel 56.

[0094] Example 4

[0095] Combined with Figure 1 For illustration, a dust removal system for a saturated or nearly saturated steam-containing dust gas includes the dust removal device provided in Example 1, an induced draft fan 7 and a dust ash recovery device. The inlet end of the induced draft fan 7 is communicated with the gas outlet 58 of the bag filter 5 through a pipeline two 6. The dust ash recovery device includes a finished product bin 10 and an enclosed belt conveyor 9.

[0096] The dust removal device is erected above the enclosed belt conveyor 9 for cooling and humidifying the solid material after coal pyrolysis and the finished product bin 10. Among them, a disc type airtight discharging valve 82 is arranged below the second ash hopper 55 of the bag filter 5, and the dust can directly fall into the finished product bin 10 through the valve. A screw discharging machine 81 is arranged below the first ash hopper 37 to convey the dust into the finished product bin 10.

[0097] Example 5

[0098] Combined with Figure 4 For illustration, different from Example 4, the dust removal device provided in Example 3 is selected to replace the dust removal device provided in Example 1.

[0099] Example 6

[0100] Combined with Figure 1A dust removal method for a dust-containing gas of saturated or near-saturated steam includes the following steps: First, open the hot flue gas pipeline 2 to preheat the horizontal centrifugal mixer 3 and the bag filter 5 to 130-160 °C. Subsequently, introduce the dust-containing gas of saturated or near-saturated steam. According to the flow rate of the dust-containing gas of saturated or near-saturated steam, the temperature of the mixed gas, and the humidity of the dust removal ash, adjust the flow rate of the hot flue gas to control the inlet temperature of the bag filter at 110-180 °C. After detection, the moisture content of the obtained dust removal ash is 5-16%, avoiding the easy dusting of the dust removal ash due to being too dry.

[0101] Application Example

[0102] During the pyrolysis of low-rank coal using the low-temperature rotating bed technology, the dust concentration in the obtained steam is 10-15 g / m 3 , the temperature is 80-110 °C, the humidity is between 50-100%, and the steam contains some oil and gas; the temperature of the flue gas for coal pyrolysis is between 150-300 °C.

[0103] Adopt the dust removal system provided in Example 3. Before production, first preheat the dust removal system to 130-160 °C with waste heat flue gas at 180-260 °C, and then introduce the dust-containing gas. According to the temperature of the mixed gas and the humidity of the dust removal ash, adjust the flow rate of the hot flue gas to control the inlet temperature of the bag filter ≥110 °C. The dust discharge of the dust collector is continuous dry ash, and the external water content of the discharged ash is about 10%. It not only meets the economic requirements of air mixing but also meets the gas transportation requirements of the dust removal ash. After long-term operation, disassemble the dust collector to check the surface of the filter bag, and no bag sticking phenomenon is found, and the gas collection chamber is clean without dust, meeting the requirements of up-to-standard discharge.

[0104] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements on some or all of the technical features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A dust removal device for a dusty gas containing saturated or nearly saturated steam, characterized in that, It includes a horizontal centrifugal mixer (3) and a bag filter (5); The horizontal centrifugal mixer (3) includes a barrel-shaped housing (31) arranged horizontally, a dust-containing gas pipeline (1) located at both ends of the barrel-shaped housing (31) respectively, and a mixed gas outlet. The mixed gas outlet, the dust-containing gas pipeline (1) and the barrel-shaped housing (31) are coaxially arranged. The air inlet (54) of the bag filter (5) is communicated with the mixed gas outlet; A spiral blade (32) is arranged in the barrel-shaped housing (31). A hot flue gas pipeline (2) is arranged at one end of the barrel-shaped housing (31) close to the dust-containing gas pipeline (1). The inlet direction of the hot flue gas pipeline (2) is arranged along the tangential direction of the barrel-shaped housing (31); A hopper one (35) for collecting dust removal ash is arranged at one end of the barrel-shaped housing (31) below and close to the mixed gas outlet.

2. The dust removal device according to claim 1, wherein A perforated plate (52) is arranged in the bag filter (5). The perforated plate (52) divides the bag filter (5) into an upper box body (51) and a middle box body (53). Filter units (57) are correspondingly arranged on the perforated plate (52) and are located in the middle box body (53). The air inlet (54) is located on the middle box body (53); Preferably, an upward air guiding channel (56) is arranged in the middle box body (53). The air guiding channel (56) is communicated with the air inlet (54); Preferably, a hopper two (55) for collecting dust removal ash is arranged below the middle box body (53); Preferably, a gas outlet (58) is arranged on the upper box body (51); Preferably, an air backwashing unit (59) is arranged at the top of the filter unit (57); Preferably, the filtering material of the filter unit (57) is any one of PTFE, PPS or acrylic.

3. The dust removal device according to claim 2, wherein The air guiding channel (56) includes a flat plate (561) and a vertical plate (562). The vertical plate (562), the flat plate (561) and the middle box body (53) cooperate with each other to form the air guiding channel (56); Preferably, the vertical distance between the plane where the top end of the vertical plate (562) is located and the lower end surface of the perforated plate (52) is 0.3 - 1 m; Preferably, a plurality of flow dividing plates (563) are arranged in the air guiding channel (56). The plurality of flow dividing plates (563) cooperate with the air guiding channel (56) to disperse the gas in different directions; Preferably, the bottom of the flow dividing plate (563) is connected to the flat plate (561). The top surface height of the flow dividing plate (563) is the same as the top surface height of the air inlet (54); Preferably, the plurality of flow dividing plates (563) are distributed in a fan shape along the surface of the flat plate (561).

4. The dust removal device according to claim 2, characterized in that, The air guiding channel (56) is a pipeline structure; Preferably, the vertical distance between the plane where the air outlet end of the pipeline structure is located and the lower end surface of the perforated plate (52) is 1 / 3 - 1 of the diameter of the pipeline structure; Preferably, the pipeline structure includes a vertical straight pipe and an elbow. One end of the elbow is communicated with the air inlet (54), and the other end of the elbow is communicated with the bottom of the vertical straight pipe.

5. The dust removal device according to claim 1, characterized in that, Both ends of the barrel-shaped housing (31) are respectively provided with a ring-shaped housing one (33) and a ring-shaped housing two (34). The ring-shaped housing one (33) is provided at the mixed gas outlet, and the ring-shaped housing two (34) is communicated with the dust-containing gas pipeline (1). Preferably, the mixed gas outlet is communicated with the air inlet (54) through a pipeline one (4).

6. A dust removal system for a dusty gas containing saturated or nearly saturated steam, characterized in that, It includes the dust removal device according to any one of claims 1 to 5, a draft fan (7) and a dust removal ash recovery device. The draft fan (7) is communicated with the air outlet of the bag filter (5), and the dust removal ash recovery device is located below the dust removal device.

7. The dust removal system according to claim 6, wherein, The dust removal ash recovery device includes a finished product bin (10), and the finished product bin (10) is respectively communicated with a hopper one (35) and a hopper two (55). Preferably, the dust removal ash recovery device further includes an enclosed belt conveyor (9) communicated with the finished product bin (10). Preferably, the finished product bin (10) is communicated with the hopper one (35) through a screw discharger (81) or a disc air lock discharger (82). Preferably, the finished product bin (10) is communicated with the hopper two (55) through a screw discharger (81) or a disc air lock discharger (82).

8. The dust removal system according to claim 6, wherein, The draft fan (7) is communicated with the gas outlet (58) through a pipeline two (6).

9. A method for removing dust from a dust-containing gas of saturated or nearly saturated steam, characterized in that, It includes preheating the horizontal centrifugal mixer (3) by introducing hot flue gas through a hot flue gas pipeline (2), then introducing dust-containing gas through a dust-containing gas pipeline (1), mixing the dust-containing gas and the hot flue gas through the horizontal centrifugal mixer (3) to obtain a mixed gas, transporting the mixed gas to the bag filter (5) for dust removal, and simultaneously recovering the dust removal ash collected by the horizontal centrifugal mixer (3) and the bag filter (5).

10. The dust removal method according to claim 9, wherein The temperature of the preheating is 130 - 160 °C. Preferably, the temperature of the mixed gas is 110 - 180 °C. Preferably, the moisture content of the dust removal ash is 5 - 16%. Preferably, the temperature of the hot flue gas is 150 - 300 °C, preferably 180 - 260 °C. Preferably, the hot flue gas is industrial flue gas.

Images