A coal-fired boiler flue gas treatment system and flue gas treatment process

Abstract

The present invention relates to the technical field of flue gas treatment, and in particular to a flue gas treatment system and a flue gas treatment process for a coal-fired boiler, wherein a flue gas treatment system for a coal-fired boiler comprises a dust removal module, a denitration module and a desulfurization module, the flue gas treated by the denitration module is transported to the interior of a desulfurization tower of the desulfurization module through a smoke inlet, the flue gas enters a first chamber through a through hole on a partition plate, slurry enters a second chamber through the through hole, the slurry reacts with oxygen again to generate a precipitate, and the precipitate is discharged from the denitration tower through a discharge pipe, and at the same time, a control unit changes the liquid level in the second chamber when the oxygen concentration in the first chamber is greater than a second preset value, after the liquid level in the second chamber is changed, the movement path of oxygen in entering the second chamber increases, and the contact time between the slurry and oxygen is increased, thereby ensuring that the slurry can fully react with the oxygen, thereby improving the desulfurization efficiency of the flue gas.

Description

Technical Field

[0001] The present invention relates to the technical field of flue gas treatment, and in particular to a flue gas treatment system and a flue gas treatment process for a coal-fired boiler. Background Art

[0002] During the operation of coal-fired boilers, the flue gas contains a large amount of pollutants, especially sulfur dioxide, which can cause great harm to the environment and human health. Therefore, the flue gas treatment system of coal-fired boilers usually needs to be equipped with a desulfurization tower to reduce the emission of sulfur dioxide in the flue gas. Among the current desulfurization technologies, wet desulfurization is the most widely used method. It mainly passes lime slurry and oxidizing air into the flue gas in the desulfurization tower, so that sulfur dioxide reacts with the slurry to form calcium sulfate, thereby achieving the desulfurization effect.

[0003] During the operation of the desulfurization tower, the oxidizing air in the bottom slurry pool is difficult to fully contact and react with the slurry, resulting in partial oxidizing air escaping and being unable to be fully absorbed by the slurry, which not only causes a waste of oxidizing air, but also may affect the desulfurization effect. In addition, in long-term operation, the slurry pool in the desulfurization tower is prone to accumulate impurities, resulting in increased slurry viscosity, which hinders the slurry from fully contacting with flue gas and oxidizing air. This phenomenon not only causes wear and corrosion of the equipment, but also increases the maintenance cost and downtime of the system, thereby reducing the desulfurization efficiency. Summary of the invention

[0004] The invention provides a coal-fired boiler flue gas treatment system and a flue gas treatment process to solve the problem of low desulfurization efficiency of the existing desulfurization tower for the flue gas of the coal-fired boiler.

[0005] A coal-fired boiler flue gas treatment system and flue gas treatment process of the present invention adopts the following technical solutions:

[0006] A coal-fired boiler flue gas treatment system comprises a dust removal module, a denitrification module and a desulfurization module.

[0007] The dust removal module is used to filter the flue gas; the denitrification module is used to denitrify the flue gas treated by the dust removal module; the desulfurization module is used to desulfurize the flue gas treated by the denitrification module; wherein the desulfurization module includes a desulfurization tower, an oxygen supply pipe, a discharge pipe and a regulating bag; the desulfurization tower has a desulfurization chamber inside, and the desulfurization tower is provided with a smoke inlet and a smoke outlet connecting the external environment and the desulfurization chamber, wherein the smoke inlet is arranged below the smoke outlet; a partition plate is arranged in the desulfurization chamber, and the partition plate is arranged between the smoke inlet and the smoke outlet, and the partition plate can separate the desulfurization chamber into a first chamber and a second chamber, and a plurality of through holes are arranged on the partition plate, and the first chamber is located above the second chamber ; A shotcrete pipe is provided in the first chamber, a reflux pipe is provided in the second chamber, and a circulating pump is provided on the desulfurization tower. The circulating pump can supply desulfurizer into the shotcrete pipe, and the circulating pump can extract excess desulfurizer from the second chamber through the reflux pipe; the oxygen supply pipe is used to supply oxygen into the second chamber; the discharge pipe runs through the denitrification tower, one end of the discharge pipe is provided at the lower end of the second chamber, and a filter is provided at one end of the discharge pipe in the second chamber, and the filter is used to prevent materials with a diameter greater than a first preset value from entering the discharge pipe; the adjustment control is used to change the liquid level in the second chamber when the oxygen concentration in the first chamber is greater than a second preset value, and the second preset value is a manually set parameter.

[0008] Furthermore, the spraying pipe is provided with a plurality of spraying holes in the first chamber, and the plurality of spraying holes are all opened downward, and each spraying hole is on the same vertical line as a through hole.

[0009] Furthermore, a plurality of spoiler blades are arranged on the partition plate, and the spoiler blades are used to guide the flue gas to fully contact with the desulfurizer.

[0010] Furthermore, a plurality of oxygen supply tubes are provided, and the plurality of oxygen supply tubes are located at the same horizontal plane in the second chamber. A plurality of air outlet holes are provided on each oxygen supply tube, and the plurality of air outlet holes are all opened upward.

[0011] Furthermore, the control unit includes a gas detector, a control panel and a plurality of control capsules, wherein the plurality of control capsules are fixedly arranged in the second chamber, and the volumes of the plurality of control capsules can change; the gas detector is arranged in the first chamber, and the gas detector is used to detect the concentration of oxygen in the first chamber, and when the concentration of oxygen in the first chamber is greater than a second preset value, the control panel adjusts the volume of the control capsules to increase.

[0012] Furthermore, the control unit also includes a control pump, which is fixedly mounted on the denitrification tower. The control pump has multiple air supply pipes, each of which is connected to a control bag. The control panel can control the control pump. When the concentration of oxygen in the first chamber is greater than the second preset value, the control panel controls the control pump to supply air to the multiple control bags.

[0013] Furthermore, a fixed plate is provided in the second chamber, and a plurality of regulating capsules are fixedly provided on the fixed plate; a plurality of discharge holes are provided on the fixed plate, and a plurality of discharge pipes are provided, each discharge hole is connected to a discharge pipe, and a plurality of regulating capsules are provided around each discharge hole. When the volume of the plurality of regulating capsules increases, the plurality of regulating capsules can extrude and crush materials with a diameter greater than the first preset value.

[0014] Furthermore, the filter element includes a plurality of filter plates, a plurality of filter holes are arranged on the filter plates, the aperture of the filter holes is a first preset value, and each filter plate is arranged on a discharge hole.

[0015] Furthermore, a demister is provided at the smoke outlet, and the demister is used to process the water vapor discharged from the desulfurization chamber.

[0016] A coal-fired boiler flue gas treatment process, using the above-mentioned coal-fired boiler flue gas treatment system, comprises the following steps:

[0017] S1, transports the flue gas generated by the coal-fired boiler to the dust removal module;

[0018] S2, transporting the flue gas treated by the dust removal module to the denitrification module;

[0019] S3, transporting the flue gas treated by the denitrification module to the desulfurization module;

[0020] S4, discharges the flue gas treated by the desulfurization module into the atmosphere.

[0021] The beneficial effects of the present invention are as follows: a coal-fired boiler flue gas treatment system and a flue gas treatment process of the present invention, wherein the coal-fired boiler flue gas treatment system includes a dust removal module, a denitrification module and a desulfurization module. When the flue gas generated by the coal-fired boiler is treated, the flue gas generated by the coal-fired boiler is transported to the dust removal module, the dust removal module can treat large particle impurities in the flue gas, and then the denitrification module is used to treat the flue gas treated by the dust removal module to reduce the concentration of nitrogen oxides in the flue gas. Subsequently, the flue gas treated by the denitrification module is transported to the inside of the desulfurization tower of the desulfurization module through the smoke inlet. Under the action of the partition plate, the flue gas is in the second chamber, and the flue gas enters the first chamber through the through hole on the partition plate. At this time, the circulating pump supplies desulfurizer to the shotcrete pipe, and at the same time, the oxygen supply pipe supplies the desulfurizer to the first chamber. Oxygen is supplied to the second chamber, and the product after the sulfur-containing substances in the flue gas react with the desulfurizer forms slurry with part of the desulfurizer. The slurry enters the second chamber through the through hole, and the slurry reacts with oxygen again to generate precipitate. The precipitate accumulates at the bottom of the second chamber, and the precipitate is discharged from the denitrification tower through the discharge pipe. The filter element prevents materials with a diameter greater than the first preset value from entering the discharge pipe, thereby preventing materials with a diameter greater than the first preset value from clogging the discharge pipe. At the same time, the control element changes the liquid level in the second chamber when the oxygen concentration in the first chamber is greater than the second preset value. After the liquid level in the second chamber changes, the movement path of oxygen in entering the second chamber increases, which increases the contact time between the slurry and oxygen, thereby ensuring that the slurry can fully react with oxygen, thereby improving the desulfurization efficiency of the flue gas. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0023] Figure 1 A schematic structural diagram of a desulfurization module in a coal-fired boiler flue gas treatment system provided in an embodiment of the present invention;

[0024] Figure 2 A simplified flow chart of a coal-fired boiler flue gas treatment system provided by an embodiment of the present invention;

[0025] Figure 3 A schematic diagram of a partially cutaway structure of a desulfurization module in a coal-fired boiler flue gas treatment system provided by an embodiment of the present invention;

[0026] Figure 4 for Figure 3 A partial enlarged view of point A in the middle.

[0027] In the figure: 110, desulfurization tower; 120, smoke inlet; 130, smoke outlet; 140, partition plate; 160, spraying pipe; 170, reflux pipe; 180, circulation pump; 190, discharge pipe; 210, spoiler blade; 220, regulating bag; 230, filter plate; 240, fixed plate; 250, demister; 260, filter press; 270, oxygen supply pipe; 280, connecting pipe; 310, regulating pump; 320, air supply pipe. DETAILED DESCRIPTION

[0028] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0029] The serial numbers assigned to the components herein, such as "first", "second", etc., are only used to distinguish the objects described and do not have any order or technical meaning. The "connection" and "coupling" mentioned in this application, unless otherwise specified, include direct and indirect connections (couplings). In the description of the present invention, it should be understood that the orientation or position relationship indicated by the terms "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", etc. are based on the orientation or position relationship shown in the accompanying drawings, which is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation to the present invention.

[0030] 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 that 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.

[0031] like Figures 1 to 4 As shown, an embodiment of the present invention provides a coal-fired boiler flue gas treatment system, which includes a dust removal module, a denitrification module and a desulfurization module.

[0032] The dust removal module is used to filter the flue gas. Specifically, the dust removal module is a bag dust removal module. The flue gas from the coal-fired boiler is passed into the bag. The flue gas can diffuse outward through the bag. The large particles in the flue gas can be intercepted inside the bag. After the flue gas passes through the bag, the concentration of particulate matter in the flue gas is less than or equal to 10 mg per standard cubic meter.

[0033] The denitrification module is used to denitrify the flue gas treated by the dust removal module. Denitrification treatment is to reduce the concentration of nitrogen oxides in the flue gas. After denitrification treatment, the emission concentration of nitrogen oxides in the flue gas is less than or equal to 50 mg per standard cubic meter.

[0034] The desulfurization module is used to desulfurize the flue gas treated by the denitrification module. The desulfurization treatment is to reduce the concentration of sulfur dioxide in the flue gas. After the desulfurization treatment, the sulfur dioxide emission concentration in the flue gas is less than or equal to 35 mg per standard cubic meter. Specifically, the desulfurization module includes a desulfurization tower 110, an oxygen supply pipe 270, a discharge pipe 190 and a control capsule 220.

[0035] The desulfurization tower 110 is slightly cylindrical in shape, the axis of the desulfurization tower 110 is vertically arranged, the interior of the desulfurization tower 110 is hollow, the hollow chamber inside the desulfurization tower 110 is a desulfurization chamber, the desulfurization tower 110 is provided with a smoke inlet 120 and a smoke outlet 130 connecting the external environment and the desulfurization chamber, the smoke inlet 120 is arranged in the middle of the desulfurization tower 110 in the vertical direction, and the flue gas after denitrification is transported to the desulfurization chamber through the smoke inlet 120. The smoke outlet 130 is arranged at the upper end of the desulfurization tower 110, and the flue gas passes through the interior of the desulfurization tower 110 and is discharged from the desulfurization chamber through the smoke outlet 130. A partition plate 140 is provided in the desulfurization chamber. The partition plate 140 is provided between the smoke inlet 120 and the smoke outlet 130. The partition plate 140 can separate the desulfurization chamber into a first chamber and a second chamber. The first chamber is located above the second chamber. The partition plate 140 is provided with a plurality of through holes. The plurality of through holes can connect the first chamber with the second chamber. The smoke inlet 120 is connected with the second chamber, and the smoke outlet 130 is connected with the first chamber. After the flue gas enters the second chamber, the flue gas can pass through the through holes and enter the first chamber. A spraying pipe 160 is provided in the first chamber, a reflux pipe 170 is provided in the second chamber, and a circulating pump 180 is provided on the desulfurization tower 110. The circulating pump 180 can supply desulfurizer to the spraying pipe 160, and the circulating pump 180 can extract the excess desulfurizer from the second chamber through the reflux pipe 170. Specifically, when the circulation pump 180 is started, the desulfurizer is sprayed into the first chamber through the spray pipe 160. When the flue gas enters the first chamber through the through hole, the flue gas contacts the desulfurizer, the sulfur dioxide in the flue gas contacts the water in the desulfurizer and reacts chemically to generate sulfurous acid, the sulfur trioxide in the flue gas contacts the water in the desulfurizer and reacts chemically to generate sulfuric acid, the sulfurous acid and sulfuric acid react with the desulfurizer to generate calcium sulfate and calcium sulfite, the calcium sulfate, calcium sulfite and the excess desulfurizer that does not participate in the reaction form a slurry, the slurry enters the second chamber through the through hole, and accumulates in the second chamber, the desulfurizer that does not participate in the reaction leaves the second chamber through the reflux pipe 170, and returns to the first chamber again through the spray pipe 160, and at the same time, calcium sulfate and calcium sulfite may still be carried away by the reflux pipe 170. In this embodiment, the desulfurizer is a calcium carbonate solution.

[0036] The oxygen supply pipe 270 is used to supply oxygen to the second chamber. When the oxygen enters the second chamber, the oxygen reacts chemically with calcium sulfite to generate calcium sulfate. When the calcium sulfate contacts water, the calcium sulfate can react with water to generate calcium sulfate dihydrate, which can be deposited at the bottom of the second chamber.

[0037] The discharge pipe 190 is arranged through the denitration tower, one end of the discharge pipe 190 is arranged at the lower end of the second chamber, and a filter is arranged at one end of the discharge pipe 190 in the second chamber, and the filter is used to prevent materials with a diameter greater than the first preset value from entering the discharge pipe 190. Specifically, one end of the discharge pipe 190 is in the second chamber, and the other end of the discharge pipe 190 is provided with an extraction pump, which can extract calcium sulfate dihydrate deposited at the bottom of the second chamber from the second chamber, and the filter prevents materials with a diameter greater than the first preset value from entering the discharge pipe 190, thereby preventing materials with a diameter greater than the first preset value from damaging the discharge pipe 190.

[0038] The control unit is used to change the liquid level in the second chamber when the oxygen concentration in the first chamber is greater than a second preset value. When oxygen enters the first chamber, it proves that the oxygen is not completely consumed in the second chamber, and further proves that the calcium sulfite in the second chamber has not fully reacted with the oxygen. At this time, the control unit increases the liquid level in the second chamber. After the liquid level in the second chamber is changed, the movement path of oxygen entering the second chamber increases, which increases the contact time between the slurry and oxygen, thereby ensuring that the slurry can fully react with oxygen, thereby improving the desulfurization efficiency of the flue gas.

[0039] A coal-fired boiler flue gas treatment system of the present invention, when treating the flue gas generated by the coal-fired boiler, transports the flue gas generated by the coal-fired boiler to a dust removal module, the dust removal module can treat large particle impurities in the flue gas, and then uses a denitrification module to treat the flue gas treated by the dust removal module to reduce the concentration of nitrogen oxides in the flue gas. Subsequently, the flue gas treated by the denitrification module is transported to the inside of a desulfurization tower 110 of a desulfurization module through a smoke inlet 120. Under the action of a partition plate 140, the flue gas is in a second chamber, and the flue gas enters the first chamber through a through hole on the partition plate 140. At this time, a circulating pump 180 supplies a desulfurizer to a spraying pipe 160, and at the same time, an oxygen supply pipe 270 supplies oxygen to the second chamber, and sulfur-containing substances in the flue gas are The product after the desulfurizer reaction forms slurry with part of the desulfurizer, and the slurry enters the second chamber through the through hole, and the slurry reacts with oxygen again to generate precipitate, which accumulates at the bottom of the second chamber, and is discharged from the denitrification tower through the discharge pipe 190. The filter element prevents materials with a diameter greater than the first preset value from entering the discharge pipe 190, and prevents materials with a diameter greater than the first preset value from clogging the discharge pipe 190. At the same time, the control element changes the liquid level in the second chamber when the oxygen concentration in the first chamber is greater than the second preset value. After the liquid level in the second chamber changes, the movement path of oxygen in entering the second chamber increases, which increases the contact time between the slurry and oxygen, thereby ensuring that the slurry can fully react with oxygen, thereby improving the desulfurization efficiency of the flue gas.

[0040] In one embodiment, the spray pipe 160 is provided with a plurality of spray holes in the first chamber, and the plurality of spray holes are all opened downward, and each spray hole is on the same vertical line as a through hole. Specifically, the spray pipe 160 is spirally arranged in the first chamber, and the plurality of spray holes are evenly distributed along the length direction of the spray pipe 160. A nozzle is provided at each spray hole, and the desulfurizer can be sprayed outward through the nozzle. By arranging each spray hole and a through hole on the same vertical line, it is ensured that the desulfurizer sprayed from the nozzle can fully contact the flue gas flowing into the first chamber at the through hole, thereby ensuring that the sulfur dioxide gas in the flue gas can fully react with the calcium carbonate solution after reacting with water.

[0041] In one embodiment, a plurality of spoiler blades 210 are provided on the partition plate 140, each of which can rotate in a through hole, and the spoiler blades 210 are used to guide the flue gas to fully contact with the desulfurizer. Furthermore, the spoiler blades 210 can form a turbulence enhancer when combined with the through hole, and the turbulence enhancer can also flow part of the gas, while also greatly improving the turbulence effect, increasing the mass transfer efficiency, and thus improving the stability of the flue gas entering the first chamber through the through hole.

[0042] In one embodiment, a plurality of oxygen supply pipes 270 are provided, and the plurality of oxygen supply pipes 270 are located at the same horizontal plane in the second chamber, and the horizontal plane where the plurality of oxygen supply pipes 270 are located is located below the smoke inlet 120, and the plurality of oxygen supply pipes 270 are arranged parallel to each other in the second chamber, and each oxygen supply pipe 270 is provided with a plurality of air outlets, and the plurality of air outlets are all opened upward, and the plurality of oxygen supply pipes 270 all penetrate the desulfurization tower 110, and one end of the plurality of oxygen supply pipes 270 outside the desulfurization tower 110 is connected to each other through a connecting pipe 280. An oxygen supply pump is provided on the connecting pipe 280, and the oxygen supply pump is used to continuously supply oxygen into the connecting pipe 280. The oxygen enters the second chamber from the air outlet on each oxygen supply pipe 270. Since there is slurry formed by calcium sulfate, calcium sulfite and excess desulfurizer that does not participate in the reaction in the second chamber, when oxygen contacts the slurry, the oxygen reacts with the calcium sulfite in the slurry. By providing multiple oxygen supply pipes 270 and each oxygen supply pipe 270 with multiple air outlets, it is ensured that oxygen can fully convert calcium sulfite into calcium sulfate.

[0043] In one embodiment, the control unit includes a gas detector, a control panel, and a plurality of control capsules 220. The plurality of control capsules 220 are fixedly disposed in the second chamber. The volumes of the plurality of control capsules 220 can change. Furthermore, in the initial state, the volumes of the control capsules 220 are in the minimum state. The gas detector is disposed in the first chamber. The gas detector is used to detect the concentration of oxygen in the first chamber. During normal operation, the oxygen supply of the oxygen supply pump is regulated to ensure that the oxygen entering the second chamber can be just absorbed by the calcium sulfite in the second chamber, and then there is no oxygen in the first chamber. If the concentration of oxygen in the first chamber is greater than the second preset value, the control board adjusts the volume of the control capsule 220 to increase. Specifically, the second preset value is a manually set parameter, and the second preset value can be set on the control board. When the data detected by the gas detector is transmitted to the control board, the control board can compare and analyze the received data with the second preset value. If the data detected by the gas detector is greater than the second preset value, the control board controls the volume of the control capsule 220 to increase. Since the control capsule 220 is fixed in the second chamber, when the volume of the control capsule 220 increases, the control capsule 220 squeezes the slurry in the second chamber, so that the liquid level of the slurry in the second chamber increases. Accordingly, the path of oxygen flowing from bottom to top in the second chamber increases, ensuring that the oxygen can fully react with the calcium sulfite in the slurry.

[0044] In one of the embodiments, the control unit also includes a control pump 310, which is fixedly mounted on the denitrification tower. The control pump 310 has multiple air supply pipes 320, each of which is connected to a control bag 220. When the control pump 310 is started, the control pump 310 can extract the gas inside the control bag 220 through the air supply pipe 320, or the control pump 310 can supply gas to the inside of the control bag 220 through the air supply pipe 320. In the initial state, the gas inside the control bag 220 is in the minimum state, that is, the volume of the control bag 220 is in the minimum state. The control panel can regulate the regulating pump 310. When the concentration of oxygen in the first chamber is greater than the second preset value, the control panel controls the regulating pump 310 to supply air to the multiple regulating capsules 220. The volume of the regulating capsules 220 increases, and the regulating capsules 220 squeeze the slurry in the second chamber, so that the liquid level of the slurry in the second chamber increases. Accordingly, the path of oxygen flowing from bottom to top in the second chamber increases, ensuring that the oxygen can fully react with the calcium sulfite in the slurry.

[0045] In one embodiment, a fixed plate 240 is provided in the second chamber, a plurality of regulating capsules 220 are fixedly provided on the fixed plate 240, the fixed plate 240 is provided below the horizontal plane where the plurality of oxygen supply pipes 270 are located, and the fixed plate 240 is fixedly connected to the inner side wall of the desulfurization tower 110. In this embodiment, the fixed plate 240 is fixedly connected to the lower end surface of the desulfurization tower 110. A plurality of discharge holes are provided on the fixed plate 240, and a plurality of discharge pipes 190 are provided, each discharge hole is connected to a discharge pipe 190. Since the discharge pipe 190 passes through the lower end surface of the desulfurization tower 110, the discharge pipe 190 is connected to the discharge hole after passing through the lower end of the desulfurization tower 110, and the calcium sulfate dihydrate deposited at the bottom of the second chamber can enter the inside of the discharge pipe 190 through the discharge hole, and the calcium sulfate dihydrate can be discharged from the desulfurization tower 110 through the discharge pipe 190. There are multiple regulating capsules 220 around each discharge hole. Specifically, the discharge hole and the regulating capsules 220 are both arranged on the fixed plate 240. By adjusting the positions of the discharge hole and the regulating capsules 220, it is ensured that there are multiple regulating capsules 220 around each discharge hole. When the volume of the multiple regulating capsules 220 increases, the multiple regulating capsules 220 can squeeze and crush materials with a diameter greater than a first preset value. Materials with a diameter greater than the first preset value cannot enter the discharge pipe 190, and materials with a diameter greater than the first preset value accumulate on the fixed plate 240. When the volume of the regulating capsules 220 increases, the multiple regulating capsules 220 squeeze and crush calcium sulfate dihydrate with a diameter greater than the first preset value, ensuring that the calcium sulfate dihydrate can be discharged from the desulfurization tower 110 through the discharge pipe 190.

[0046] In one embodiment, the filter element includes a plurality of filter plates 230, a plurality of filter holes are provided on the filter plates 230, the aperture of the filter holes is a first preset value, and each filter plate 230 is provided on a discharge hole. Specifically, by setting the aperture of the filter holes, it is ensured that calcium sulfate dihydrate with a diameter greater than the first preset value cannot enter the discharge pipe 190, thereby reducing the probability of damage to the discharge pipe 190.

[0047] In one embodiment, a demister 250 is provided at the smoke outlet 130, and the demister 250 is used to process the water vapor discharged from the desulfurization chamber. In order to reduce the water content of the smoke discharged from the smoke outlet 130, the demister 250 is provided to process the water vapor in the smoke, so as to ensure that the water content of the smoke discharged from the smoke outlet 130 is within a preset range.

[0048] In one embodiment, a filter press 260 is provided on the discharge pipe 190, and the filter press 260 is used to filter and remove impurities from the calcium sulfate dihydrate and calcium carbonate solution entering the discharge pipe 190, ensuring that the material discharged from the discharge pipe 190 is only calcium sulfate dihydrate.

[0049] A coal-fired boiler flue gas treatment process, using a coal-fired boiler flue gas treatment system, specifically includes the following steps:

[0050] S1, the flue gas generated by the coal-fired boiler is transported to the dust removal module. Specifically, the dust removal module is a bag dust removal module, which passes the flue gas from the coal-fired boiler into the bag, and the flue gas can diffuse outward through the bag, and the large particles in the flue gas can be intercepted inside the bag. After the flue gas passes through the bag, the concentration of particulate matter in the flue gas is less than or equal to 10 mg per standard cubic meter.

[0051] S2, transporting the flue gas treated by the dust removal module to the denitration module. Specifically, the denitration module is used to denitrate the flue gas treated by the dust removal module. The denitration treatment is to reduce the concentration of nitrogen oxides in the flue gas. After the denitration treatment, the emission concentration of nitrogen oxides in the flue gas is less than or equal to 50 mg per standard cubic meter.

[0052] S3, transporting the flue gas treated by the denitration module to the desulfurization module. Specifically, the sulfur module is used to perform desulfurization treatment on the flue gas treated by the denitration module. The desulfurization treatment is to reduce the concentration of sulfur dioxide in the flue gas. After the desulfurization treatment, the sulfur dioxide emission concentration in the flue gas is less than or equal to 35 mg per standard cubic meter.

[0053] S4, the flue gas treated by the desulfurization module is discharged into the atmosphere. After being treated by the dust removal module, the denitrification module and the desulfurization module, the components in the flue gas meet the emission standards, so the flue gas is discharged into the atmosphere, thereby reducing the impact on the air environment.

[0054] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A coal-fired boiler flue gas treatment system, characterized in that: include: Dust removal module, the dust removal module is used to filter the smoke; Denitrification module: the denitrification module is used to denitrify the flue gas after being treated by the dust removal module; Desulfurization module, which is used to desulfurize the flue gas treated by the denitrification module; The desulfurization module includes a desulfurization tower, an oxygen supply pipe, a discharge pipe and a control bag; The desulfurization tower has a desulfurization chamber inside, and is provided with a smoke inlet and a smoke outlet connecting the external environment and the desulfurization chamber, wherein the smoke inlet is arranged below the smoke outlet; a partition plate is arranged in the desulfurization chamber, and the partition plate is arranged between the smoke inlet and the smoke outlet, and the partition plate can separate the desulfurization chamber into a relatively isolated first chamber and a second chamber, and a plurality of through holes are arranged on the partition plate, and the first chamber is located above the second chamber; a spraying pipe is arranged in the first chamber, and a reflux pipe is arranged in the second chamber, and a circulating pump is arranged on the desulfurization tower, and the circulating pump can supply desulfurizer to the spraying pipe, and the circulating pump can extract excess desulfurizer from the second chamber through the reflux pipe; The oxygen supply tube is used for supplying oxygen into the second chamber; A discharge pipe is arranged to pass through the denitration tower, one end of the discharge pipe is arranged at the lower end of the second chamber, and a filter is arranged at one end of the discharge pipe in the second chamber, and the filter is used to prevent materials with a diameter greater than a first preset value from entering the discharge pipe; a control unit includes a gas detector, a control board and a plurality of control capsules, a fixed plate is arranged in the second chamber below the horizontal plane where the oxygen supply pipe is located, and a plurality of control capsules are fixedly arranged on the fixed plate, and the volumes of the plurality of control capsules can change; the gas detector is arranged in the first chamber to detect the concentration of oxygen in the first chamber, and when the concentration of oxygen in the first chamber is greater than the second preset value, the control board adjusts the volume of the control capsule to increase so as to change the liquid level in the second chamber; a plurality of discharge holes are arranged on the fixed plate, and a plurality of discharge pipes are arranged, each discharge hole is connected to a discharge pipe, and a plurality of control capsules are arranged around each discharge hole, and when the volumes of the plurality of control capsules increase, the plurality of control capsules can squeeze and crush materials with a diameter greater than the first preset value.

2. The coal-fired boiler flue gas treatment system according to claim 1, characterized in that: The spraying pipe is provided with a plurality of spraying holes in the first chamber, and the plurality of spraying holes are all opened downward, and each spraying hole is on the same vertical line as a through hole.

3. The coal-fired boiler flue gas treatment system according to claim 1, characterized in that: A plurality of spoiler blades are arranged on the partition plate, and the spoiler blades are used to guide the flue gas to fully contact with the desulfurizer.

4. The coal-fired boiler flue gas treatment system according to claim 1, characterized in that: A plurality of oxygen supply pipes are provided, and the plurality of oxygen supply pipes are located at the same horizontal plane in the second chamber. A plurality of air outlet holes are provided on each oxygen supply pipe, and the openings of the plurality of air outlet holes are all arranged to face upward.

5. The coal-fired boiler flue gas treatment system according to claim 1, characterized in that: The control unit also includes a control pump, which has multiple air supply pipes, each of which is connected to a control bag. The control panel can control the control pump. When the concentration of oxygen in the first chamber is greater than the second preset value, the control panel controls the control pump to supply air to the multiple control bags.

6. The coal-fired boiler flue gas treatment system according to claim 1, characterized in that: The filter element comprises a plurality of filter plates, on which a plurality of filter holes are arranged, the aperture of the filter holes is a first preset value, and each filter plate is arranged on a discharge hole.

7. The coal-fired boiler flue gas treatment system according to claim 1, characterized in that: A demister is provided at the smoke outlet, and is used to process the water vapor discharged from the desulfurization chamber.

8. A coal-fired boiler flue gas treatment process, using the coal-fired boiler flue gas treatment system according to any one of claims 1 to 7, characterized in that: The following steps are involved: S1, transports the flue gas generated by the coal-fired boiler to the dust removal module; S2, transporting the flue gas treated by the dust removal module to the denitrification module; S3, transporting the flue gas treated by the denitrification module to the desulfurization module; S4, discharges the flue gas treated by the desulfurization module into the atmosphere.

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