Systems for treating dusty exhaust gases

Abstract

The invention discloses a system for treating dust-containing tail gas, comprising: a combustion-dust removal-dust collection device, comprising: a combustion section, which has a dust-containing tail gas inlet, a combustion-supporting gas inlet and a heat source; a dust removal section, which is connected to the combustion section and has an annular tube, and a plurality of holes facing the inner wall of the dust removal section are evenly distributed along the circumference of the annular tube; a dust collection section, which is connected to the dust removal section and is provided with a filler, a liquid atomizer and a gas outlet after dust collection, the liquid atomizer is located above the filler, and the gas outlet after dust collection is located above the liquid atomizer; a slurry outlet, which is connected to the dust removal section and the dust collection section; a pH adjustment device, which has a slurry inlet, a slurry outlet after slurry adjustment, a pH adjustment agent inlet and a pH detector, and the slurry outlet extends below the liquid surface of the pH adjustment device; a liquid-solid separation device, which is provided with a filter element, a slurry inlet after slurry adjustment, a slag slurry outlet and a liquid outlet after filtration, and the liquid outlet after filtration is connected to the annular tube and the liquid atomizer; a gas purification device, which has an adsorption layer, a gas inlet after dust collection and a gas outlet after purification.

Description

Technical Field

[0001] The present invention belongs to the technical field of tail gas treatment, and in particular, relates to a system for treating dust-containing tail gas. Background Art

[0002] In the manufacturing process of integrated circuits and LED panels, a variety of silicon-containing substances are used in chemical vapor deposition, such as trichlorosilane, dichlorosilane, silane, disilane, tetraethyl orthosilicate, octamethylcyclotetrasiloxane, polysilazane, tetramethylsilane, trimethylsilane, etc.; in the manufacturing process of optical fiber preforms, the main raw material used for vapor deposition is silicon tetrachloride. After these gases participate in the reaction, they are discharged in the form of tail gas. At the same time, the above-mentioned gases will also produce tail gas during the filling and replacement process. Some of the above-mentioned toxic and harmful gases that are process raw materials or reaction by-products have the characteristics of corrosiveness, toxicity, flammability and explosion, and need to be treated to meet the standards before being discharged to avoid safety accidents and environmental pollution.

[0003] Integrated circuit, LED panel and optical fiber manufacturing companies mainly use heat treatment to burn exhaust gas, and the heat treatment is in the form of electric heating or combustion. When treating silicon-containing gas, acidic gases such as silicon dioxide and hydrogen chloride will be produced after combustion. The solid waste and exhaust gas produced need to be treated, otherwise it will cause environmental pollution. Existing technologies mostly use water washing or bag dust collection to treat; there are also a small number of dry adsorption and catalytic oxidation methods to treat exhaust gas, that is, using adsorbents or catalysts to adsorb or catalytically convert exhaust gas for treatment, but due to the high cost of adsorption media and catalysts, and facing the problem of waste disposal, this type of method is less used; plasma exhaust gas processors use electrical energy to excite and decompose the relevant exhaust gas at high temperature, and the processing volume is small. At the same time, supporting dust collection and exhaust gas treatment facilities are also required.

[0004] That is, in the existing tail gas treatment methods, the method of treating tail gas by dry adsorption and catalytic oxidation is less used because of the high cost of adsorption media and catalysts, and faces the problem of waste disposal and small processing volume. Plasma tail gas processors use electrical energy to excite and decompose the relevant tail gas at high temperature, but the processing volume is small, and it also requires supporting dust collection and tail gas treatment facilities, and the scope of use is small. Therefore, at present, combustion combined with water washing or bag dust collection is more commonly used to treat silicon-based tail gas.

[0005] The silica dust generated in the process of treating silicon-containing tail gas is very small and easily condenses to block pipes or equipment, causing the equipment to fail to operate normally, thereby affecting the operation of the main system. To address this problem, a study has adopted the method of setting a scraper inside the combustion cylinder to mechanically remove the silica deposited on the inner wall of the combustion cylinder. There are two problems with this solution. First, the mechanical seal of the transmission part is prone to leakage, especially when dealing with flammable and explosive gases such as silane, which is extremely dangerous. Second, the scraper itself will also deposit silica particles, and the system needs to be shut down for cleaning, affecting the operation of the production system.

[0006] When water is used for leaching, if the leaching water is unevenly distributed, there may be liquid dead zones in some areas, resulting in poor dust collection effects, and fine particles are discharged into the atmosphere, causing environmental pollution; at the same time, the capture of hydrogen chloride in the tail gas will produce acidic wastewater, which will cause environmental pollution if discharged without effective treatment, and the use of neutral circulating water for leaching is poor and consumes a lot of water. In order to reduce operating costs, there is a plan to recycle the leaching water, but the leaching water contains a large amount of solid silica, and the particles are extremely fine, at the micron level, and it is not easy to filter through a simple filter, so that the fine particles of silica enter the spray system and cause blockage. At the same time, the leaching water is acidic wastewater and corrosive, and has certain requirements for the filter material. The solid particles accumulated in the leaching water discharged to the outside are not separated, which is easy to cause blockage of subsequent pipelines and facilities.

[0007] After the exhaust gas is burned, when the bag dust collector is used for dust collection, the cost of replacing the bag is high. When the water content or oil content in the exhaust gas is high, the bag is easy to stick, and eventually the system cannot operate normally. In addition, the acidic gas such as hydrogen chloride produced by the combustion is not effectively treated, causing environmental pollution. And when multiple bags are arranged, if individual bags are broken, it takes a long time to determine the broken bag position.

[0008] Therefore, the existing technology for treating tail gas needs to be further improved. Summary of the invention

[0009] The present invention aims to solve one of the technical problems in the related art to at least a certain extent. To this end, one purpose of the present invention is to propose a system for treating dust-containing exhaust gas. The use of this system can significantly improve the efficiency of treating dust-containing exhaust gas, so that dust and harmful gases in the dust-containing exhaust gas can be efficiently captured, and solid particles can be effectively taken out of the system to avoid solid particles clogging the filler or entering the subsequent system. At the same time, the clean discharge of exhaust gas can be achieved, and the phenomenon of stopping for maintenance during operation can be avoided. The recycling of liquid can be achieved, and the consumption of new water and alkali or acid can be significantly reduced.

[0010] In one aspect of the present invention, the present invention provides a system for treating dust-containing tail gas, wherein the dust-containing tail gas refers to dust-containing tail gas containing dust and harmful gases and / or dust-containing tail gas containing dust and harmful gases after combustion. According to an embodiment of the present invention, the system includes:

[0011] A combustion-dust removal-dust collection device, the combustion-dust removal-dust collection device comprising:

[0012] A combustion section, wherein the combustion section has a dust-containing tail gas inlet, a combustion-supporting gas inlet and a heat source;

[0013] A dust removal section, the dust removal section is connected to the combustion section, and the dust removal section is provided with an annular tube. On the dust removal section provided with the annular tube, the annular tube is located on the cross section of the dust removal section, the outer wall of the annular tube is at a distance from the inner wall of the dust removal section, and a plurality of holes facing the inner wall of the dust removal section are evenly distributed along the circumference of the annular tube;

[0014] A dust collecting section, the dust collecting section is connected to the dust removal section, the dust collecting section is provided with a filler, a liquid atomizer and a gas outlet after dust collection, the liquid atomizer is located above the filler, and the gas outlet after dust collection is located above the liquid atomizer;

[0015] A slurry outlet, the slurry outlet is located between the dust removal section and the dust collection section, is connected to the dust removal section and the dust collection section, and is suitable for discharging the slurry in the dust removal section and the dust collection section;

[0016] A pH adjusting device, wherein the pH adjusting device has a slurry inlet, a slurry outlet after slurry adjustment and a pH adjusting agent inlet, and a pH detector is provided in the pH adjusting device, the slurry inlet is connected to the slurry outlet, and the slurry outlet extends below the liquid surface of the pH adjusting device to form a liquid seal;

[0017] A liquid-solid separation device, wherein the liquid-solid separation device is provided with a filter element, a slurry inlet after slurry adjustment, a slurry outlet and a filtered liquid outlet, the slurry inlet after slurry adjustment is connected to the slurry outlet after slurry adjustment, and the filtered liquid outlet is connected to the ring pipe and the liquid atomizer through a pipeline;

[0018] A gas purification device, wherein an adsorption layer is provided in the gas purification device, and has a dust-collected gas inlet and a purified gas outlet, the adsorption layer is located in the middle of the gas purification device, the dust-collected gas inlet is located at the bottom of the gas purification device and is connected to the dust-collected gas outlet, and the purified gas outlet is located at the top of the gas purification device.

[0019] According to the system for treating dust-containing exhaust gas of an embodiment of the present invention, in the combustion-dust removal-dust collection device, the dust-containing exhaust gas can be fully burned under the action of a heat source and a combustion-supporting gas to obtain dust and harmful gases; an annular tube is provided in the dust removal section, the outer wall of the annular tube is close to the inner wall of the dust removal section, and a plurality of holes facing the inner wall of the dust removal section are evenly distributed along the circumference of the annular tube. When liquid is passed into the annular tube, the liquid can flow out through the holes and form a uniform liquid film on the inner wall of the dust removal section. The liquid film can clean the inner wall of the dust removal section and wash away the dust attached to the inner wall of the dust removal section. At the same time, the liquid film can also capture the gas soluble in the liquid film in the harmful gas, thereby reducing the content of harmful gases entering the subsequent process; when gas is passed into the annular tube, the gas can pass through the annular tube. The liquid flows out through the holes and forms a uniform air film on the inner wall of the dust removal section, so that the liquid and / or adhered dust on the inner wall of the dust removal section are blown off. That is, by arranging an annular tube in the dust removal section and uniformly arranging a plurality of holes on the annular tube along the circumferential direction toward the inner wall of the dust removal section, liquid phase dust removal and / or gas phase dust removal can be achieved in the dust removal section, so as to avoid the deposition of dust and the occurrence of problems such as poor sealing, and there will be no need to stop the machine for cleaning, which is beneficial to extending the operation cycle of the equipment. After dust removal in the dust removal section, dust with larger particle size is discharged from the slurry outlet along with the liquid film and / or air film, and dust with smaller particle size is sent to the dust collecting section along with the airflow. At the same time, the captured harmful gas is also discharged from the slurry outlet, and the uncaptured harmful gas is sent to the dust collecting section along with the airflow. By arranging fillers and liquid atomizers in the dust collecting section, the surface of the fillers is conducive to the landing of small dust particles, and the liquid atomizer atomizes the liquid, which is conducive to increasing the surface area of ​​the liquid particles, thereby increasing the contact area between the liquid particles and the small dust particles, and improving the dust collecting effect. At the same time, it is also conducive to increasing the contact area between the liquid particles and the gas, thereby increasing the yield of harmful gases in the airflow, and further reducing the content of harmful gases in the dust-collected gas discharged from the dust collecting section. The dust recovered by the dust collecting section and the harmful gases dissolved in the liquid can be discharged from the slurry outlet along with the liquid flow. The slurry discharged from the slurry outlet from the dust removal section and the dust collection section is sent to the pH adjustment device. By setting a pH detector in the device, the current pH value of the slurry can be known in real time. When the pH value of the slurry is not conducive to the capture of harmful gases, acid or alkali can be added in time to ensure that the pH value of the slurry is conducive to the capture of harmful gases during the entire treatment process, which is conducive to improving the capture of harmful gases and reducing the content of harmful gases in the gas after dust collection. By extending the slurry outlet to the liquid level of the pH adjustment device to form a liquid seal, harmful gas leakage can be prevented and environmental pollution can be avoided. After the slurry after slurry adjustment is sent to the liquid-solid separation device, under the action of the filter element, the solid particles in the slurry are separated on the outer wall of the filter element, which can effectively take the solid particles out of the system to prevent the solid particles from clogging the filler or entering the subsequent process. The obtained filtered liquid can be sent to the ring pipe and the liquid atomizer as the leaching liquid of the dust removal section and the dust collection section, respectively, to achieve the recycling of liquid and reduce the amount of new water replenishment and the consumption of alkali or acid.The dust-collected gas discharged from the dust collection section can be completely absorbed by the adsorption layer in the gas purification device, which can completely absorb the harmful gases that are not absorbed in the dust removal section and the dust collection section, so that the purified gas meets the national and regional emission standards and achieves clean exhaust gas emission. Therefore, the use of this system can significantly improve the efficiency of treating dust-containing exhaust gas, so that the dust and harmful gases in the dust-containing exhaust gas can be efficiently captured, and the solid particles can be effectively taken out of the system to avoid solid particles clogging the filler or entering the subsequent system. At the same time, the clean exhaust gas emission can be achieved, and the phenomenon of shutdown maintenance during operation can be avoided. It can also realize the recycling of liquids and significantly reduce the consumption of new water and alkali or acid.

[0020] In addition, the system for treating dust-containing tail gas according to the above embodiment of the present invention may also have the following additional technical features:

[0021] In some embodiments of the present invention, the heat source is an electric heating rod or combustible gas combustion for heating.

[0022] In some embodiments of the present invention, a cooling device is provided on the outer wall of the combustion section.

[0023] In some embodiments of the present invention, the cooling device is a heat exchange jacket or an external accompanying pipe.

[0024] In some embodiments of the present invention, a plurality of the ring tubes are included, preferably three.

[0025] In some embodiments of the present invention, the plurality of ring tubes are distributed at equal intervals in the height direction.

[0026] In some embodiments of the present invention, the shortest distance between the outer wall of the annular tube and the inner wall of the dust removal section accounts for 10-20% of the distance from the inner wall of the dust removal section to the central axis of the annular tube.

[0027] In some embodiments of the present invention, each of the ring tubes is provided with no less than 3 holes.

[0028] In some embodiments of the present invention, the diameter of the hole is 1-10 mm, preferably 4 mm.

[0029] In some embodiments of the present invention, the angle between the plane where the hole is located and the inner wall of the dust removal section is 30-70 degrees, preferably 45 degrees.

[0030] In some embodiments of the present invention, the filler is at least one of a ball ring and a wire mesh.

[0031] In some embodiments of the present invention, the material of the filler is selected from at least one of metal, ceramic and tetrafluoroethylene.

[0032] In some embodiments of the present invention, the specific surface area of ​​the wire mesh is 100 to 500 m 2 / m 3 , preferably 200m 2 / m 3 .

[0033] In some embodiments of the present invention, the height of the filler is 10-30 cm, preferably 15 cm.

[0034] In some embodiments of the present invention, in the height direction, the distance between the liquid atomizer and the filler is 30-200 mm.

[0035] In some embodiments of the present invention, a plurality of the fillers and a plurality of the liquid atomizers are included, the number of the fillers being the same as that of the fillers.

[0036] In some embodiments of the present invention, the pH adjusting device includes a slurry collecting tank and a pH adjusting agent containing tank, the slurry inlet, the slurry outlet after slurry adjustment, the pH adjusting agent inlet and the pH detector are located in the slurry collecting tank, the pH adjusting agent containing tank is connected to the pH adjusting agent inlet through a pump, and the pH detector is connected to the pump.

[0037] In some embodiments of the present invention, the filtered liquid outlet is connected to the liquid-solid separation device.

[0038] In some embodiments of the present invention, a plurality of the liquid-solid separation devices are included, preferably two.

[0039] In some embodiments of the present invention, the filtered liquid outlet of each of the liquid-solid separation devices is connected to at least another of the liquid-solid separation devices.

[0040] In some embodiments of the present invention, the liquid-solid separation device includes a plurality of the filter elements, and a filter element distributor is provided in the liquid-solid separation device, and the plurality of the filter elements are detachably connected to the filter element distributor.

[0041] In some embodiments of the present invention, a plurality of the filter elements are evenly distributed on the filter element distributor.

[0042] In some embodiments of the present invention, the filtering accuracy of the filter element is not less than 0.1 μm.

[0043] In some embodiments of the present invention, a first solenoid valve is provided on the pipeline connecting the filtered liquid outlet and the ring pipe.

[0044] In some embodiments of the present invention, a second solenoid valve is provided on the pipeline connecting the filtered liquid outlet and the liquid atomizer.

[0045] In some embodiments of the present invention, a plurality of the gas purification devices are included.

[0046] In some embodiments of the present invention, the purified gas outlet of each gas purification device is connected to the dust-collected gas inlet of another gas purification device.

[0047] In some embodiments of the present invention, the pressure of the liquid or gas introduced into the annular tube is 2-6 bar, preferably 4 bar.

[0048] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0050] Figure 1 is a schematic diagram of the structure of a system for treating dust-containing tail gas according to an embodiment of the present invention;

[0051] Figure 2 is a schematic diagram of the structure of a system for treating dust-containing tail gas according to another embodiment of the present invention;

[0052] Figure 3 is a schematic diagram of the structure of a system for treating dust-containing tail gas according to another embodiment of the present invention;

[0053] Figure 4 is a schematic diagram of the structure of a system for treating dust-containing tail gas according to another embodiment of the present invention;

[0054] Figure 5 is a schematic diagram of the structure of a system for treating dust-containing tail gas according to another embodiment of the present invention;

[0055] Figure 6 is a schematic diagram of the structure of a system for treating dust-containing tail gas according to another embodiment of the present invention;

[0056] Figure 7 It is a schematic diagram of the structure of a system for treating dust-containing exhaust gas according to another embodiment of the present invention. DETAILED DESCRIPTION

[0057] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and should not be construed as limiting the present invention.

[0058] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0059] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0060] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0061] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0062] In one aspect of the present invention, the present invention provides a system for treating dust-containing tail gas. According to an embodiment of the present invention, referring to Figure 1 The system includes: a combustion-dust removal-dust collection device 100, a pH adjustment device 200, a liquid-solid separation device 300 and a gas purification device 400.

[0063] According to an embodiment of the present invention, the combustion-dust removal-dust collection device 100 includes: a combustion section 110 , a dust removal section 120 , a dust collection section 130 and a slurry outlet 101 .

[0064] According to one embodiment of the present invention, the combustion section 110 has a dust-containing tail gas inlet 111, a combustion-supporting gas inlet 112 and a heat source 113, and is suitable for burning the dust-containing tail gas under the action of the heat source and the combustion-supporting gas. The inventor found that the dust-containing tail gas can be fully burned under the action of the heat source and the combustion-supporting gas to obtain dust and harmful gases. It should be noted that the dust-containing tail gas referred to in this application refers to dust-containing tail gas containing dust and harmful gases and / or containing dust and harmful gases after combustion, wherein the specific types of harmful gases can be acidic gases HF, HCl, HNO3, H2SO4 and H3PO4, etc., alkaline gases NH3, etc., toxic and corrosive gases B2H4, P2O5, BF3, etc. and organic solvent tail gases benzene, toluene, chloroform, xylene, etc. Further, the specific form of providing a heat source for the dust-containing tail gas is not particularly limited, and those skilled in the art can choose according to actual needs, such as heating by an electric heating rod or directly burning combustible gas in the combustion section for heating. Furthermore, the specific temperature value provided by the heat source is not particularly limited, and those skilled in the art can select it according to the dust-containing exhaust gas being treated. Furthermore, in order to avoid the outer wall temperature of the combustion section being too high, a cooling device can be provided on the outer wall of the combustion section, but the specific type of cooling device is not particularly limited, and those skilled in the art can select it according to actual needs, such as a heat exchange jacket or an external companion pipe. Similarly, the specific control value of the outer wall temperature of the combustion section is not particularly limited, and can be selected according to the material of the combustion section, or according to the environment in which the combustion section is located. Furthermore, the material of the inner wall of the combustion section is not particularly limited, and can be selected according to the temperature of the dust-containing exhaust gas during combustion, so that the material of the inner wall of the combustion section is suitable for the combustion of the dust-containing exhaust gas being treated.

[0065] According to another embodiment of the present invention, the dust removal section 120 is connected to the combustion section 110, and the dust removal section 120 is provided with an annular pipe 121. On the dust removal section 120 provided with the annular pipe 121, the annular pipe 121 is located on the cross section of the dust removal section 120, that is, the plane where the annular pipe 121 is located is perpendicular to the dust removal section 120 at that location, and the outer wall of the annular pipe 121 is at a distance from the inner wall of the dust removal section 120. A plurality of holes (not shown) facing the inner wall of the dust removal section 120 are evenly distributed along the circumference of the annular pipe 121, and are suitable for passing liquid and / or gas to the dust removal section through the annular pipe and the holes set on the annular pipe. The inventor discovered that an annular tube is provided in the dust removal section, the outer wall of the annular tube is close to the inner wall of the dust removal section, and a plurality of holes facing the inner wall of the dust removal section are evenly distributed along the circumference of the annular tube. When liquid is passed through the annular tube, the liquid can flow out through the holes and form a uniform liquid film on the inner wall of the dust removal section. The liquid film can clean the inner wall of the dust removal section and wash away the dust attached to the inner wall of the dust removal section. At the same time, the liquid film can also capture the gas soluble in the liquid film in the harmful gas, thereby reducing the content of the harmful gas entering the subsequent process. When gas is passed through the annular tube, the gas can flow out through the holes and form a uniform gas film on the inner wall of the dust removal section, And / or adhered dust is blown off, that is, by arranging an annular tube in the dust removal section, and evenly arranging a plurality of holes on the annular tube along the circumferential direction toward the inner wall of the dust removal section, liquid phase dust removal and / or gas phase dust removal can be achieved in the dust removal section, avoiding the deposition of dust and the occurrence of problems such as poor sealing, and there will be no need to stop the equipment for cleaning, which is beneficial to extending the operation cycle of the equipment; after dust removal in the dust removal section, dust with larger particle size is discharged from the slurry outlet along with the liquid film and / or gas film, and dust with smaller particle size is sent to the dust collecting section along with the air flow. At the same time, the captured harmful gas is also discharged from the slurry outlet, and the uncaptured harmful gas is sent to the dust collecting section along with the air flow.

[0066] According to a specific embodiment of the present invention, the dust removal section 120 may include a plurality of loops 121, preferably 3. The inventors have found that by setting a plurality of loops in the dust removal section, the dust removal and the capture effect of harmful gases in the dust removal section can be improved, dust can be prevented from adhering to the inner wall of the dust removal section, and harmful gases can be captured as much as possible. Further, when a plurality of loops are set in the dust removal section, since the loops can pass gas or liquid, during operation, whether each loop is opened at the same time, when to open, and whether each loop passes gas or liquid is not subject to special restrictions, and those skilled in the art can make a choice according to the actual working conditions, such as multiple loops can be opened in sequence from top to bottom, and the next loop can be opened after the previous loop is closed; gas phase dust removal and liquid phase dust removal can be operated continuously or intermittently as needed, such as liquid can be passed to each loop first, and then gas can be passed to the loops in sequence, or liquid and gas can be passed to the exchange loops in a cross manner. Thus, the dust removal effect of the dust removal section can be further improved, which is more conducive to ensuring that all dust is sent to the next process. Furthermore, when the dust removal section contains multiple annular tubes, the distribution form of the multiple annular tubes in the dust removal section is not particularly limited, such as the multiple annular tubes can be distributed at equal intervals in the height direction. Therefore, even if the pressure of the liquid or gas sent to each annular tube is consistent, dust removal and harmful gases can be well captured. Further, when it is necessary to pass gas to the annular tube, the annular tube can be connected to an external gas source. The specific type of gas source is also not particularly limited, such as air or nitrogen. Further, in the horizontal direction, the shortest distance between the outer wall of the annular tube and the inner wall of the dust removal section is not particularly limited. Those skilled in the art can choose according to the pressure of the airflow or liquid flow leading to the annular tube, as long as the airflow can cover the entire inner wall of the dust removal section after being ejected from the hole and the inner wall of the dust removal section can be purged, or the liquid flow can cover the entire inner wall of the dust removal section after being ejected from the hole and the dust adhering to the inner wall of the dust removal section can be removed. Specifically, in the horizontal direction, the shortest distance between the outer wall of the annular tube and the inner wall of the dust removal section can account for 10-20% of the distance from the inner wall of the dust removal section to the central axis of the annular tube. The inventors found that if the shortest distance between the outer wall of the annular tube and the inner wall of the dust removal section is too small, the hole on the annular tube is too close to the inner wall of the dust removal section, so that the contact area between the gas or liquid sprayed from the annular tube hole and the inner wall of the dust collector is too small, and the airflow or liquid flow coverage area is small, resulting in the situation that the airflow or liquid flow cannot effectively cover some areas of the inner wall of the dust collector. If the shortest distance between the outer wall of the annular tube and the inner wall of the dust removal section is too large, the hole on the annular tube is too far away from the inner wall of the dust removal section, so that the force of the airflow or liquid flow sprayed from the annular tube hole when reaching the inner wall of the dust collector is reduced, and the dust with strong adhesion cannot be effectively removed.

[0067] According to another specific embodiment of the present invention, the number, diameter and opening direction of the holes on the annular tube are not particularly limited, and those skilled in the art can select according to actual needs. For example, each annular tube can be provided with no less than 3 holes, the diameter of the hole can be 1-10 mm, preferably 4 mm, and the angle between the plane where the hole is located and the inner wall of the dust removal section can be 30-70 degrees, preferably 45 degrees. The inventor found that if the number of holes is too small, the generated airflow or liquid flow will not be able to completely cover the inner wall of the dust removal section, and the dust cannot be effectively removed; if the number of holes is too large, on the one hand, it will cause the airflow or liquid flow to enter the annular tube. The hole close to the annular tube inlet has a large airflow or liquid flow, and the hole far away from the annular tube inlet has a small airflow or liquid flow, and the small airflow or liquid flow will result in a small injection force of the airflow or liquid flow, and the dust removal effect on the inner wall of the dust removal section is poor; on the other hand, when the airflow and liquid flow are constant, if the number of holes is too large, the average airflow or liquid flow delivered to each hole is small, resulting in a small injection force of the airflow or liquid flow, and the dust removal effect on the inner wall of the dust removal section is poor. If the diameter of the hole is too small, the amount of airflow or liquid ejected from the hole will be small, resulting in a small coverage area of ​​the airflow or liquid flow, and there may be a problem that the inner wall of the dust removal section cannot be fully covered; if the diameter of the hole is too large, the airflow or liquid flow ejected from the hole will be weak, and the dust removal effect on the inner wall of the dust removal section will be poor. If the angle between the plane where the hole is located and the inner wall of the dust removal section is too small, the coverage area of ​​the ejected airflow or liquid flow on the inner wall of the dust removal section will be small, and there may be a problem that the airflow or liquid flow cannot fully cover the inner wall of the dust removal section; if the angle between the plane where the hole is located and the inner wall of the dust removal section is too large, the ejected airflow or liquid flow cannot cover the area corresponding to the ring pipe, resulting in the inability to remove dust from the inner wall of the dust removal section here.

[0068] According to another specific embodiment of the present invention, the pressure of the liquid or gas introduced into the annular tube is not particularly limited, and those skilled in the art can select it according to actual needs, such as 2-6 bar, preferably 4 bar. The inventors found that when the pressure is low, the jet force of the airflow or liquid flow is small, and the dust removal effect on the inner wall of the dust collector is poor. A moderate pressure can meet the use requirements. If the pressure is too high, the requirements for the supporting pipelines, valves and equipment are increased, the operating costs are increased, and the economy is poor.

[0069] According to another embodiment of the present invention, the dust collecting section 130 is connected to the dust removing section 120, and the dust collecting section 130 is provided with a filler 131, a liquid atomizer 132 and a gas outlet 133 after dust collection, the liquid atomizer 132 is located above the filler 131, and the gas outlet 133 after dust collection is located above the liquid atomizer 132, and is suitable for capturing dust and harmful gases in the airflow after dust removal. The inventor found that by arranging the filler and the liquid atomizer in the dust collecting section, the surface of the filler is conducive to the landing of small particles of dust, and the liquid atomizer is conducive to increasing the surface area of ​​the liquid particles by atomizing the liquid, thereby increasing the contact area between the liquid particles and the small particles of dust, improving the dust collection effect, and at the same time, it is also conducive to increasing the contact area between the liquid particles and the gas, thereby increasing the yield of harmful gases in the airflow, and further reducing the content of harmful gases in the gas after dust collection discharged from the dust collecting section, and the dust recovered by the dust collecting section and the harmful gases dissolved in the liquid can be discharged from the slurry outlet along with the liquid flow.

[0070] According to a specific embodiment of the present invention, the specific type and material of the filler are not particularly limited. For example, the filler can be at least one of a ball ring and a wire mesh, and the material of the filler can be selected from at least one of metal, ceramic and tetrafluoroethylene. The inventors have found that this type of filler has a large surface area, which is beneficial to improving the dust collection effect of the dust collection section. Furthermore, when the filler contains a wire mesh, the specific surface area of ​​the wire mesh can be 100 to 500 m 2 / m 3 , preferably 200m 2 / m 3 . The inventors have found that if the specific surface area of ​​the filler is too low, the contact area provided by the filler is small, the liquid-solid contact area is limited, and the solid particles cannot be effectively supplemented; if the specific surface area of ​​the filler is too high, the resistance to gas passing through the filler is too large, which will cause poor airflow inside the equipment, easily leading to particle aggregation and blockage. Furthermore, the height of the filler is not particularly limited, such as 10-30cm, preferably 15cm. The inventors have found that if the height of the filler is too low, the contact area provided by the filler is small, the liquid-solid contact is limited, and the solid particles cannot be effectively supplemented; if the height of the filler is too high, the resistance to gas passing through is too large, resulting in poor airflow inside the equipment, easily leading to particle aggregation and blockage.

[0071] According to another specific embodiment of the present invention, the distance and relative position between the liquid atomizer and the filler are not particularly limited. For example, the liquid atomizer can be located directly above the center of the filler and 30 to 200 mm away from the filler in the height direction. The inventor found that if the distance between the liquid atomizer and the filler is too small, the droplets sprayed by the liquid atomizer will cover a small area and cannot fully cover the filler. There is no liquid or little liquid in the area not covered by the droplets, and the liquid-solid exchange is not thorough, and the solid particles cannot be effectively supplemented. If the distance between the liquid atomizer and the filler is too large, part of the droplets sprayed by the liquid atomizer will be sprayed on the inner wall of the equipment and flow downward along the inner wall of the equipment. When the liquid flow sent to the liquid atomizer is constant, the liquid sprayed directly above the filler will be relatively reduced, which will lead to incomplete liquid-solid exchange and ineffective collection of solid particles. Furthermore, the number of fillers and liquid atomizers in the dust collection section is not particularly limited. For example, it can include multiple fillers and multiple liquid atomizers that match the number of fillers. It should be noted that when there are multiple fillers and multiple liquid atomizers, the liquid atomizer is located between two fillers in the height direction, which is beneficial to improving the dust collection effect and efficiency of the dust collection section.

[0072] According to another embodiment of the present invention, the slurry outlet 101 is located between the dust removal section 120 and the dust collection section 130, and is connected to the dust removal section 120 and the dust collection section 130, and is suitable for discharging the slurry in the dust removal section and the dust collection section.

[0073] According to an embodiment of the present invention, the pH adjusting device 200 has a slurry inlet 201, a slurry outlet 202 after slurry adjustment and a pH adjusting agent inlet 203, and a pH detector 21 is provided in the pH adjusting device 200. The slurry inlet 201 is connected to the slurry outlet 101, and the slurry outlet 101 extends below the liquid surface of the pH adjusting device 200 to form a liquid seal, and is suitable for storing slurry and adjusting the pH value of the slurry when necessary. The inventors found that the slurry discharged from the slurry outlet from the dust removal section and the dust collection section is sent to a pH adjustment device. By setting a pH detector in the device, the current pH value of the slurry can be known in real time. When the pH value of the slurry is not conducive to the capture of harmful gases, acid or alkali solution can be added in time to ensure that the pH value of the slurry in the entire treatment process is conducive to the capture of harmful gases, which is beneficial to improve the capture of harmful gases and reduce the content of harmful gases in the gas after dust collection. By extending the slurry outlet below the liquid surface of the pH adjustment device to form a liquid seal, harmful gases can be prevented from leaking and environmental pollution can be avoided.

[0074] It should be noted that the specific method of adjusting the pH value in the pH adjusting device is not particularly limited. For example, the pH value can be adjusted by manual control, and acid or alkali solution can be added to the pH adjusting device manually; or it can be adjusted by automatic control. For example, according to one embodiment of the present invention, reference Figure 2 The pH adjusting device 200 includes a slurry collecting tank 210 and a pH adjusting agent holding tank 220. The slurry inlet 201, the adjusted slurry outlet 202, the pH adjusting agent inlet 203 and the pH detector 21 are located in the slurry collecting tank 210. The pH adjusting agent inlet 203 is connected to the pH adjusting agent holding tank 220 through a pump 22, and the pH detector 21 is connected to the pump 22. The inventor found that when the pH value of the slurry is not conducive to the capture of harmful gases, that is, when the pH value of the slurry is greater than the upper limit of the required slurry pH value or less than the lower limit of the required slurry pH value, the pH detector transmits a signal to the pump, and the pump connected to the pH detector automatically starts to transport acid or alkali solution to the slurry collecting tank until the pH value of the slurry returns to the set range.

[0075] According to an embodiment of the present invention, a filter element 31, a slurry inlet 301 after slurry adjustment, a slurry outlet 302 and a filtered liquid outlet 303 are provided in the liquid-solid separation device 300. The slurry inlet 301 after slurry adjustment is connected to the slurry outlet 202 after slurry adjustment, and the filtered liquid outlet 303 is connected to the ring pipe 121 and the liquid atomizer 132 through a pipeline, and is suitable for liquid-solid separation of the slurry after slurry adjustment, so as to obtain filtered liquid and slurry. The inventor found that after the slurry after slurry adjustment is sent to the liquid-solid separation device, under the action of the filter element, the solid particles in the slurry are separated on the outer wall of the filter element, which can effectively take the solid particles out of the system, avoid the solid particles from clogging the filler or entering the subsequent process, and the obtained filtered liquid can be sent to the ring pipe and the liquid atomizer for use as the leaching liquid of the dust removal section and the dust collection section respectively, so as to realize the recycling of liquid and reduce the amount of new water replenishment and the consumption of alkali solution or acid solution.

[0076] According to one embodiment of the present invention, referring to Figure 3 , the filtered liquid outlet 303 can be connected to the liquid-solid separation device 300. The inventors found that when the dust attached to the outer wall of the filter element reaches a certain thickness, the operating resistance of the liquid-solid separation device will increase significantly. Before this, the obtained filtered liquid can be returned to the liquid-solid separation device to flush the dust on the outer wall of the filter element and discharge it from the slurry outlet to ensure the smooth operation of the liquid-solid separation device. Furthermore, multiple liquid-solid separation devices can be set, preferably 2. This is conducive to improving the efficiency of liquid-solid separation of the system. Further, refer to Figure 4, the filtered liquid outlet 303 of each liquid-solid separation device 300 can be connected to at least another liquid-solid separation device 300, and is suitable for sending the filtered liquid of one liquid-solid separation device to another liquid-solid separation device. The inventor found that by connecting the filtered liquid outlet of each liquid-solid separation device to at least another liquid-solid separation device, each liquid-solid separation device can be used in turn during the liquid-solid separation process, and when the thickness of dust attached to the outer wall of the filter element in a liquid-solid separation device causes its running resistance to increase significantly, the liquid-solid separation device can be stopped and another liquid-solid separation device can be opened, and the filtered liquid obtained by the liquid-solid separation device opened later can be sent to the previous liquid-solid separation device to wash the filter element in the previous liquid-solid separation device and wash away the dust attached to the outer wall of the filter element, thereby realizing that the liquid-solid separation process is always running and the filtered liquid can be recycled.

[0077] According to yet another embodiment of the present invention, Figure 5 The liquid-solid separation device 300 includes a plurality of filter elements 31, and a filter element distributor 32 is provided in the liquid-solid separation device 300, and the plurality of filter elements 31 are detachably connected to the filter element distributor 32, such as being connected in a threaded manner. Thus, the removal and maintenance of the filter element are convenient. Furthermore, the arrangement of the filter element on the filter element distributor is not particularly limited, such as a plurality of filter elements can be evenly distributed on the filter element distributor, thereby facilitating the even distribution of the filtered dust on the outer wall of the filter element. Furthermore, the filtering accuracy of the filter element is not particularly limited, and those skilled in the art can select it according to the particle size of the dust, such as making the filtering accuracy of the filter element satisfy the requirement of filtering out the dust with the smallest particle size contained in the slurry after slurry adjustment, such as not less than 0.1 μm.

[0078] According to another embodiment of the present invention, referring to Figure 6 A first solenoid valve 11 is provided on the pipeline connecting the filtered liquid outlet 303 and the annular tube 121, and is suitable for controlling whether liquid or gas is introduced into the annular tube; a second solenoid valve 12 is provided on the pipeline connecting the filtered liquid outlet 303 and the liquid atomizer 132, and is suitable for controlling whether liquid is introduced into the liquid atomizer. Thus, the dust removal and dust collection control of the dust removal section and the dust collection section can be realized by controlling the first solenoid valve and the second solenoid valve, thereby improving the automation degree of the system.

[0079] According to an embodiment of the present invention, an adsorption layer 41 is provided in the gas purification device 400, and has a dust-collected gas inlet 401 and a purified gas outlet 402. The adsorption layer 41 is located in the middle of the gas purification device 400, the dust-collected gas inlet 401 is located at the bottom of the gas purification device 400 and is connected to the dust-collected gas outlet 133, and the purified gas outlet 402 is located at the top of the gas purification device 400, and is suitable for adsorbing and purifying the dust-collected gas to obtain purified gas. The inventor found that the dust-collected gas discharged from the dust collection section can be completely absorbed by the adsorption layer in the gas purification device after being adsorbed, which can completely absorb the harmful gases that are not absorbed in the dust removal section and the dust collection section, so that the purified gas meets the national and regional emission standards and realizes the clean emission of tail gas.

[0080] According to one embodiment of the present invention, a plurality of gas purification devices may be included. This is beneficial to improving the purification efficiency of the gas after dust collection. Figure 7 , the purified gas outlet 402 of each gas purification device 400 is connected to the dust-collected gas inlet 401 of another gas purification device 400, thereby, the purification device can not only perform adsorption purification on the dust-collected gas in parallel, but also perform multi-stage adsorption purification on the dust-collected gas in series, thereby further ensuring the clean discharge of the purified gas. Furthermore, the specific type of the adsorption layer is not particularly limited, such as an activated carbon or adsorption resin adsorption layer, and specifically, the activated carbon adsorption layer can be a coal carbon or coconut shell carbon adsorption layer.

[0081] According to the system for treating dust-containing exhaust gas of an embodiment of the present invention, in the combustion-dust removal-dust collection device, the dust-containing exhaust gas can be fully burned under the action of a heat source and a combustion-supporting gas to obtain dust and harmful gases; an annular tube is provided in the dust removal section, the outer wall of the annular tube is close to the inner wall of the dust removal section, and a plurality of holes facing the inner wall of the dust removal section are evenly distributed along the circumference of the annular tube. When liquid is passed into the annular tube, the liquid can flow out through the holes and form a uniform liquid film on the inner wall of the dust removal section. The liquid film can clean the inner wall of the dust removal section and wash away the dust attached to the inner wall of the dust removal section. At the same time, the liquid film can also capture the gas soluble in the liquid film in the harmful gas, thereby reducing the content of harmful gases entering the subsequent process; when gas is passed into the annular tube, the gas can pass through the annular tube. The liquid flows out through the holes and forms a uniform air film on the inner wall of the dust removal section, so that the liquid and / or adhered dust on the inner wall of the dust removal section are blown off. That is, by arranging an annular tube in the dust removal section and uniformly arranging a plurality of holes on the annular tube along the circumferential direction toward the inner wall of the dust removal section, liquid phase dust removal and / or gas phase dust removal can be achieved in the dust removal section, so as to avoid the deposition of dust and the occurrence of problems such as poor sealing, and there will be no need to stop the machine for cleaning, which is beneficial to extending the operation cycle of the equipment. After dust removal in the dust removal section, dust with larger particle size is discharged from the slurry outlet along with the liquid film and / or air film, and dust with smaller particle size is sent to the dust collecting section along with the airflow. At the same time, the captured harmful gas is also discharged from the slurry outlet, and the uncaptured harmful gas is sent to the dust collecting section along with the airflow. By arranging fillers and liquid atomizers in the dust collecting section, the surface of the fillers is conducive to the landing of small dust particles, and the liquid atomizer atomizes the liquid, which is conducive to increasing the surface area of ​​the liquid particles, thereby increasing the contact area between the liquid particles and the small dust particles, and improving the dust collecting effect. At the same time, it is also conducive to increasing the contact area between the liquid particles and the gas, thereby increasing the yield of harmful gases in the airflow, and further reducing the content of harmful gases in the dust-collected gas discharged from the dust collecting section. The dust recovered by the dust collecting section and the harmful gases dissolved in the liquid can be discharged from the slurry outlet along with the liquid flow. The slurry discharged from the slurry outlet from the dust removal section and the dust collection section is sent to the pH adjustment device. By setting a pH detector in the device, the current pH value of the slurry can be known in real time. When the pH value of the slurry is not conducive to the capture of harmful gases, acid or alkali can be added in time to ensure that the pH value of the slurry is conducive to the capture of harmful gases during the entire treatment process, which is conducive to improving the capture of harmful gases and reducing the content of harmful gases in the gas after dust collection. By extending the slurry outlet to the liquid level of the pH adjustment device to form a liquid seal, harmful gas leakage can be prevented and environmental pollution can be avoided. After the slurry after slurry adjustment is sent to the liquid-solid separation device, under the action of the filter element, the solid particles in the slurry are separated on the outer wall of the filter element, which can effectively take the solid particles out of the system to prevent the solid particles from clogging the filler or entering the subsequent process. The obtained filtered liquid can be sent to the ring pipe and the liquid atomizer as the leaching liquid of the dust removal section and the dust collection section, respectively, to achieve the recycling of liquid and reduce the amount of new water replenishment and the consumption of alkali or acid.The dust-collected gas discharged from the dust collection section can be completely absorbed by the adsorption layer in the gas purification device, which can completely absorb the harmful gases that are not absorbed in the dust removal section and the dust collection section, so that the purified gas meets the national and regional emission standards and achieves clean exhaust gas emission. Therefore, the use of this system can significantly improve the efficiency of treating dust-containing exhaust gas, so that the dust and harmful gases in the dust-containing exhaust gas can be efficiently captured, and the solid particles can be effectively taken out of the system to avoid solid particles clogging the filler or entering the subsequent system. At the same time, the clean exhaust gas emission can be achieved, and the phenomenon of shutdown maintenance during operation can be avoided. It can also realize the recycling of liquids and significantly reduce the consumption of new water and alkali or acid.

[0082] The present invention is described below with reference to specific embodiments. It should be noted that these embodiments are merely illustrative and do not limit the present invention in any way.

[0083] Example

[0084] A system for treating dusty exhaust gas, such as Figure 7 As shown, the dust-containing tail gas is a silicon-containing tail gas containing trichlorosilane, dichlorosilane, silane, disilane, ethyl orthosilicate, octamethylcyclotetrasiloxane, polysilazane, tetramethylsilane, trimethylsilane, etc. The system includes:

[0085] The combustion-dust removal-dust collection device 100 comprises:

[0086] The combustion section 110 has a dusty exhaust gas inlet 111, a combustion-supporting gas inlet 112 and a heat source electric heating rod 113. The operating temperature of the electric heating rod is 800°C. The material of the inner wall of the combustion section is a high-temperature resistant material. The outer wall of the combustion section is provided with a heat exchange jacket. The heat exchange medium is water, so that the temperature of the outer wall of the combustion section does not exceed 60°C.

[0087] The dust removal section 120 is connected to the combustion section 110, and the dust removal section 120 is provided with three annular tubes 121 which are evenly spaced in the height direction. In the dust removal section 120 provided with the annular tube 121, the annular tube 121 is located on the cross section of the dust removal section 120, that is, the plane where the annular tube 121 is located is perpendicular to the dust removal section 120 at that location. In the horizontal direction, the shortest distance between the outer wall of the annular tube 121 and the inner wall of the dust removal section 120 accounts for 15% of the distance from the inner wall of the dust removal section to the central axis of the annular tube. The annular tube 121 is externally connected to an air source, and four holes (not shown) with a diameter of 4 mm are evenly distributed along the circumference of the annular tube 121 and face the inner wall of the dust removal section 120, and the angle between the plane where the holes are located and the inner wall of the dust removal section is 45 degrees.

[0088] The dust collecting section 130 is connected to the dust removing section 120. The dust collecting section 130 is provided with two packing ball rings 131 with a height of 15 cm, two liquid atomizers 132 and a gas outlet 133 after dust collection. Each packing 131 is equipped with a liquid atomizer 132. The liquid atomizer 132 is located 200 mm above the center of the packing 131 matched therewith. The gas outlet 133 after dust collection is located above the liquid atomizer 132.

[0089] The slurry outlet 101 is located between the dust removal section 120 and the dust collection section 130, and is connected to the dust removal section 120 and the dust collection section 130;

[0090] The pH adjusting device 200 comprises a slurry collecting tank 210 and a pH adjusting agent holding tank 220. The slurry collecting tank 210 comprises a slurry inlet 201, a slurry outlet 202 after slurry adjustment, a pH adjusting agent inlet 203 and a pH detector 21. The slurry inlet 201 is connected to the slurry outlet 101. The slurry outlet 101 extends below the liquid surface of the pH adjusting device 200 to form a liquid seal. The pH adjusting agent holding tank 220 is connected to the pH adjusting agent inlet 203 via a pump 22, and the pH detector 21 is connected to the pump 22.

[0091] The liquid-solid separation device 300 comprises a filter element distributor 32, a plurality of filter elements 31 with a filtration accuracy of not less than 0.1 μm, a slurry inlet 301 after slurry adjustment, a slurry outlet 302 and a filtered liquid outlet 303, wherein the slurry inlet 301 after slurry adjustment is connected to the slurry outlet 202 after slurry adjustment, the filtered liquid outlet 303 is connected to the annular pipe 121 and the liquid atomizer 132 through a pipeline, a first solenoid valve 11 is provided on the pipeline connecting the filtered liquid outlet 303 and the annular pipe 121, and a second solenoid valve 12 is provided on the pipeline connecting the filtered liquid outlet 303 and the liquid atomizer 132, a plurality of filter elements 31 are evenly distributed on the filter element distributor 32, and the plurality of filter elements 31 are detachably connected to the filter element distributor 32 through threads, and comprises two liquid-solid separation devices, and the filtered liquid outlet 303 of one liquid-solid separation device 300 is connected to the other liquid-solid separation device 300;

[0092] The gas purification device 400 is provided with a coal-based carbon adsorption layer 41, and has a dust-collected gas inlet 401 and a purified gas outlet 402. The adsorption layer 41 is located in the middle of the gas purification device 400, the dust-collected gas inlet 401 is located at the bottom of the gas purification device 400 and is connected to the dust-collected gas outlet 133, and the purified gas outlet 402 is located at the top of the gas purification device 400. It includes two gas purification devices 400, and the purified gas outlet 402 of one gas purification device 400 is connected to the dust-collected gas inlet 401 of the other gas purification device 400.

[0093] When the system is running, turn on the electric heating rod, raise the temperature to 800℃, and introduce air into the combustion section through the combustion-supporting gas inlet to assist combustion; the slurry after adjustment in the pH adjustment device is sent to the liquid-solid separation device, and after precision filtration by the filter element, open the second solenoid valve to send the filtered liquid to the liquid atomizer, and the filtered liquid is atomized by the liquid atomizer; when the pH detector value is set to less than 7, turn on the alkali solution pump to send the alkali solution in the pH adjuster tank to the slurry collection tank to adjust the pH value of the slurry. Silicon-containing tail gas enters from the dust-containing tail gas inlet of the combustion section and burns under the action of air and electric heating rods. The combustion produces silicon dioxide particles. Larger silicon dioxide particles naturally fall into the pH adjustment device. Fine silicon dioxide and hydrogen chloride enter the dust collection section from the dust removal section with the air flow, and come into contact with the filler and micron-level atomized filtered liquid. Fine silicon dioxide particles are deposited on the surface of the filler. The hydrogen chloride gas is neutralized with the alkaline filtered liquid. Both are effectively captured and enter the pH adjustment device with the liquid flow. An extremely small amount of hydrogen chloride enters the gas purification device from the gas outlet after dust collection, and is physically adsorbed by the coal carbon layer to obtain purified gas, thereby achieving safe, environmentally friendly and green emissions. The gas purification device can choose to operate in series or in parallel according to the content of hydrogen chloride in the gas after dust collection.

[0094] Open the first solenoid valves one by one from top to bottom, and the filtered liquid enters the corresponding annular tube in turn. Use a pump to pressurize the filtered liquid to 4 bar, so that it can spray and clean the inner wall of the combustion section through the holes at the bottom of the annular tube for a predetermined time, and wash off the silica attached to the inner wall of the combustion section. After completion, the first solenoid valve corresponding to the annular tube is closed, and the second first solenoid valve at the bottom is opened. In the same way, the inner wall of the combustion section in the corresponding area is cleaned one by one using the annular tube. After all is completed, compressed air is introduced into the annular tube, and the first solenoid valve is opened one by one from top to bottom. The pressure of the compressed air is 4 bar, and the inner wall of the combustion section is purged through the holes at the bottom of the annular tube to blow off the residual filtered liquid and attached silica on the inner wall of the combustion section. After completion, the first solenoid valve corresponding to the annular tube is closed, and the second first solenoid valve at the bottom is opened. In the same way, the inner wall of the combustion section in the corresponding area is purged one by one using the annular tube to clean the inner wall of the combustion section.

[0095] After the liquid-solid separation device performs solid-liquid separation, solid particles are retained and attached to the outside of the filter element. When the attachment thickness reaches a certain level, the operating resistance increases, and the outlet pressure of the liquid-solid separation device decreases, and the device is switched to the second liquid-solid separation device. A portion of the filtered liquid obtained by the second liquid-solid separation device is returned to the first liquid-solid separation device to flush the solid particles attached to the surface of the filter element in the first liquid-solid separation device. The flushing slurry is discharged through the slurry outlet at the bottom of the liquid-solid separation device, completing the cleaning of the first liquid-solid separation device. The cleaned first liquid-solid separation device is put into standby use, and when the second liquid-solid separation device needs to be cleaned, the device is switched according to the above-mentioned operation.

[0096] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0097] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may change, modify, replace and vary the above embodiments within the scope of the present invention.

Claims

1. A system for treating dusty tail gas, wherein the dusty tail gas refers to dusty tail gas containing dust and harmful gases and / or dusty tail gas containing dust and harmful gases after combustion, characterized in that: include: A combustion-dust removal-dust collection device, the combustion-dust removal-dust collection device comprising: A combustion section, wherein the combustion section has a dust-containing tail gas inlet, a combustion-supporting gas inlet and a heat source; A dust removal section, the dust removal section is connected to the combustion section, and the dust removal section is provided with an annular tube. On the dust removal section provided with the annular tube, the annular tube is located on the cross section of the dust removal section, the outer wall of the annular tube is at a distance from the inner wall of the dust removal section, a plurality of holes facing the inner wall of the dust removal section are evenly distributed along the circumference of the annular tube, and liquid and / or gas are passed to the dust removal section through the annular tube and the holes provided on the annular tube; A dust collecting section, the dust collecting section is connected to the dust removal section, the dust collecting section is provided with a filler, a liquid atomizer and a gas outlet after dust collection, the liquid atomizer is located above the filler, and the gas outlet after dust collection is located above the liquid atomizer; A slurry outlet, the slurry outlet is located between the dust removal section and the dust collection section, is connected to the dust removal section and the dust collection section, and is suitable for discharging the slurry in the dust removal section and the dust collection section; A pH adjusting device, wherein the pH adjusting device has a slurry inlet, a slurry outlet after slurry adjustment and a pH adjusting agent inlet, and a pH detector is provided in the pH adjusting device, the slurry inlet is connected to the slurry outlet, and the slurry outlet extends below the liquid surface of the pH adjusting device to form a liquid seal; A liquid-solid separation device, wherein the liquid-solid separation device is provided with a filter element, a slurry inlet after slurry adjustment, a slurry outlet and a filtered liquid outlet, the slurry inlet after slurry adjustment is connected to the slurry outlet after slurry adjustment, and the filtered liquid outlet is connected to the ring pipe and the liquid atomizer through a pipeline; A gas purification device, wherein an adsorption layer is provided in the gas purification device, and has a dust-collected gas inlet and a purified gas outlet, the adsorption layer is located in the middle of the gas purification device, the dust-collected gas inlet is located at the bottom of the gas purification device and is connected to the dust-collected gas outlet, and the purified gas outlet is located at the top of the gas purification device; The heat source is an electric heating rod or combustible gas for heating; It comprises a plurality of the annular tubes, and the plurality of the annular tubes are distributed at equal intervals in the height direction.

2. The system according to claim 1, characterized in that The outer wall of the combustion section is provided with a cooling device; The cooling device is a heat exchange jacket or an external accompanying pipe.

3. The system according to claim 1, characterized in that In the horizontal direction, the shortest distance between the outer wall of the annular tube and the inner wall of the dust removal section accounts for 10-20% of the distance from the inner wall of the dust removal section to the central axis of the annular tube; Each of the ring tubes is provided with no less than 3 holes; The diameter of the hole is 1-10 mm; The angle between the plane where the hole is located and the inner wall surface of the dust removal section is 30-70 degrees.

4. The system according to claim 1, characterized in that The filler is at least one of a ball ring and a wire mesh; The filler material is selected from at least one of metal and ceramic; The specific surface area of ​​the wire mesh is 100-500m 2 / m 3 ; The height of the filler is 10-30 cm; In the height direction, the distance between the liquid atomizer and the filler is 30-200 mm; It comprises a plurality of the fillers and a plurality of the liquid atomizers whose number matches the number of the fillers.

5. The system according to claim 1, characterized in that The pH adjusting device comprises a slurry collecting tank and a pH adjusting agent containing tank, the slurry inlet, the adjusted slurry outlet, the pH adjusting agent inlet and the pH detector are located in the slurry collecting tank, the pH adjusting agent containing tank is connected to the pH adjusting agent inlet through a pump, and the pH detector is connected to the pump.

6. The system according to claim 1, characterized in that The filtered liquid outlet is connected to the liquid-solid separation device; comprising a plurality of the liquid-solid separation devices; The filtered liquid outlet of each liquid-solid separation device is connected to at least another liquid-solid separation device; The liquid-solid separation device comprises a plurality of the filter elements, and a filter element distributor is provided in the liquid-solid separation device, and the plurality of the filter elements are detachably connected to the filter element distributor; A plurality of the filter elements are evenly distributed on the filter element distributor; The filtering accuracy of the filter element is not less than 0.1 μm.

7. The system according to claim 1, characterized in that A first solenoid valve is provided on the pipeline connecting the filtered liquid outlet and the ring pipe; A second solenoid valve is provided on the pipeline connecting the filtered liquid outlet and the liquid atomizer.

8. The system according to claim 1, characterized in that comprising a plurality of said gas purification devices; The purified gas outlet of each gas purification device is connected to the dust-collected gas inlet of another gas purification device.

9. The system according to claim 1 or 3, wherein the pressure of the liquid or gas introduced into the loop pipe is 2-6 bar.

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