Biomass boiler flue gas dust removal and denitration device

Abstract

The present application relates to the technical field of biomass material dust removal treatment, in particular to a biomass boiler flue gas dust removal and denitration device, which comprises an industrial kiln, a first-stage waste heat treatment unit, a second-stage waste heat treatment unit, a ceramic catalytic filtration unit, an induced draft fan, a chimney, a pretreatment unit, a reagent adding unit, a water storage tank and a blending unit. The flue gas is mixed with water through the pretreatment unit connecting the flue and the water storage tank, and the mixture is blended into a pickling solution with suitable temperature and pH value through the blending unit. The pickling solution is sprayed into the inner cylinder through the central pipe, and the biomass material is pickled. Meanwhile, the inner cylinder and the central pipe rotate at different speeds, and the excess pickling solution in the inner cylinder flows into the outer cylinder and is discharged to the external waste liquid collecting equipment.

Description

Technical Field

[0001] This invention relates to the field of biomass material dust removal technology, specifically a biomass boiler flue gas dust removal and denitrification device. Background Technology

[0002] Biomass boilers are devices that use biomass materials such as straw, sawdust, nutshells, and biomass pellets for heating. However, biomass fuels, especially straw and nutshells, generally contain high levels of metallic elements such as potassium and sodium. During boiler combustion, biomass materials easily form low-melting-point ash, leading to problems such as slagging, ash accumulation, and corrosion on the boiler's heating surfaces. This generates large amounts of smoke and nitrogen oxides, making it difficult to meet environmental protection requirements for flue gas emissions. Therefore, pretreatment such as dust removal, denitrification, and acid washing of biomass materials is usually required to reduce ash and harmful component content and improve subsequent combustion stability.

[0003] For biomass materials such as straw and fruit shells that contain high levels of metal elements, alkali metals can be released into the flue gas in gaseous or aerosol form during ceramic catalytic filtration. This can lead to alkali metal poisoning of the ceramic catalytic filter tube catalyst in the tail-end flue gas dust removal and denitrification equipment, causing irreversible occupation of catalytic active sites and a decrease in denitrification efficiency. Simultaneously, the generated ash easily adheres to the surface of the ceramic catalytic filter tube, making the filter cake difficult to clean and affecting the service life of the filter tube.

[0004] Existing technologies for acid washing involve large amounts of acid washing agents, resulting in high costs. The optimal pH value required varies slightly depending on the type of biomass fuel. Furthermore, the biomass material itself has a large amount of residual liquid after acid washing, and the dehydration time is long, which is not conducive to the subsequent transportation and combustion of the biomass material.

[0005] Therefore, a dust removal and denitrification device for biomass boiler flue gas is proposed. Summary of the Invention

[0006] The purpose of this invention is to provide a biomass boiler flue gas dust removal and denitrification device. The device mixes flue gas and water by connecting the flue to the water storage tank through a pretreatment unit, and then mixes them into an acid washing solution with suitable temperature and pH value through a blending unit. The acid washing solution is sprayed into the inner cylinder through the central pipe to acid wash the biomass material.

[0007] To achieve the above objectives, the present invention provides the following technical solution:

[0008] A biomass boiler flue gas dust removal and denitrification device includes an industrial kiln, a primary waste heat treatment unit, a secondary waste heat treatment unit, an induced draft fan and a chimney, a pretreatment unit, and a reactant addition unit. The industrial kiln is connected to the primary waste heat treatment unit via a flue, and the primary waste heat treatment unit is connected to the pretreatment unit via a flue. The pretreatment unit is connected to a water storage tank, a blending unit, and a ceramic catalytic filtration unit. After filtration by the ceramic catalytic filtration unit, the flue gas is discharged through the secondary waste heat treatment unit, the induced draft fan, and the chimney. The pretreatment unit includes an outer cylinder, an inner cylinder, a central tube, and a differential speed motor. The central tube is simultaneously connected to the flue of the primary waste heat treatment unit and the water pipe of the water storage tank. The blending unit is located on the axis of the central tube. The central tube sprays pickling liquid into the inner cylinder, and the differential speed motor drives the central tube and the inner cylinder to rotate at different speeds.

[0009] It is known that acid washing of biomass materials is carried out by soaking in acidic solution, which requires a large amount of acid solution. After acid washing, there will be liquid residue in the biomass materials. At this time, it is necessary to remove the liquid for a long time before it can be burned and used. Moreover, the flue gas mixture generated by industrial furnaces and kilns and the flue gas mixture generated by water are not stable. Different materials being burned will lead to instability in the flue gas mixture. Furthermore, the types of biomass materials required are also different, and they cannot be used directly through a uniform model.

[0010] In the above scheme, the central pipe is connected to the flue and water pipe of the primary waste heat treatment unit and the water storage tank, and is also connected to the mixing unit. The mixed pickling solution is sprayed into the inner cylinder as needed. The central pipe and the inner cylinder are driven by a differential speed motor to rotate at different speeds, so that the pickling solution and biomass materials are mixed more evenly. The differential rotation of the central pipe and the inner cylinder increases the impact force of the pickling solution, thereby promoting the rinsing of the biomass materials when excess pickling solution is discharged.

[0011] Preferably, the outer wall of the inner cylinder is evenly provided with several sets of separation holes, the upper part of the inner cylinder is fixedly connected to a rotating shaft, and the bottom of the inner cylinder is provided with a stirring plate; the inner cylinder is rotatably connected to the outer cylinder and the central tube, the rotating shaft is connected to a differential motor, the stirring plate is connected to the central tube, the diameter of the separation holes gradually decreases from high to low, the rotating shaft is fixedly connected to the upper part of the inner cylinder and drives the inner cylinder to rotate, and the bottom of the outer cylinder is connected to a waste liquid collection device.

[0012] In the above scheme, the differential motor drives the inner cylinder and the central tube to rotate at different speeds through the connection with the rotating shaft. The pickling solution flows into the inner cylinder through the central tube. During the relative rotation of the inner and outer cylinders, a certain amount of pickling solution will remain at the bottom of the inner cylinder. The excess flue gas mixture will flow into the outer cylinder through the separation hole under centrifugal action. The separation hole with gradually decreasing diameter from high to low, combined with the centrifugal action of the inner cylinder, will form a U-shaped surface of the biomass material under centrifugal action. The biomass material at the higher horizontal position has less biomass material and requires less pickling solution. At the same time, the biomass material at the higher horizontal position is in contact with less pickling solution and is easier to discharge through the separation hole. This makes the pickling of the biomass material more uniform, reduces the occurrence of excessive liquid residue, and facilitates the subsequent transportation and combustion of the biomass material.

[0013] Preferably, the blending unit includes a blending device and a blending tube; a blade is provided at the bottom of the central tube, the blending tube is disposed inside the central tube, and several sets of through holes are uniformly arranged on the outside of the central tube.

[0014] In the above scheme, since the generated flue gas mixture is not stable, the mixture is transferred to the central tube through the blending equipment and blending pipe to form an pickling solution that meets the preparation requirements. At the same time, the temperature of the flue gas cannot fully meet the requirements after passing through the primary waste heat treatment unit. At this time, the blending equipment adjusts the temperature of the flue gas mixture so that the pH value and temperature of the pickling solution meet the preparation requirements.

[0015] Preferably, a nozzle is provided at the through hole.

[0016] In the above scheme, the nozzles at the through holes increase the flow rate of the pickling solution when it flows out from the central tube, and disperse the pickling solution to form a porous jet, so as to make it more uniformly contacted with the biomass material.

[0017] Preferably, the outer wall of the mixing pipe is provided with several sets of baffles, the baffles are connected to the mixing pipe, and the baffles are inclined on the outer side near the bottom; the baffles include a top plate, a bottom plate provided below the top plate, and several sets of corrugated plates evenly distributed between the top plate and the bottom plate.

[0018] In the above scheme, since the initial flue gas mixture is still at a higher temperature than the optimal temperature required after passing through the first-stage waste heat treatment unit, by setting up several sets of baffles, the blending liquid of the mixed cold water flows from the blending pipe through the baffles into the central pipe. The blending liquid will generate turbulence under the obstruction of multiple sets of corrugated plates, thereby making the blending liquid and the flue gas mixture more uniformly mixed.

[0019] Preferably, the baffles are arranged from top to bottom away from the central pipe axis relative to the inner side of the mixing pipe.

[0020] Preferably, the inner side of the baffle is configured as an inlet perpendicular to the wall of the mixing pipe, and the top plate, the corrugated plate and the bottom plate grow uniformly from top to bottom.

[0021] In the above scheme, the baffle is set to move away from the mixing pipe from top to bottom, so that the water flow velocity gradually slows down from top to bottom. Since the temperature of the flue gas mixture in the central pipe is higher than that of the mixing liquid in the mixing pipe, the flue gas mixture entering the central pipe from the bottom will rise due to buoyancy and form convection with the upper mixing liquid with a higher flow velocity, which further increases the mixing speed and uniformity of the pickling solution.

[0022] Preferably, the tail liquid from the ceramic catalytic filtration unit is collected, filtered, and then transferred to the blending equipment.

[0023] In the above scheme, the ceramic catalytic filtration unit will produce acidic tail liquid after catalysis. By collecting and filtering the acidic tail liquid, it can be used to modulate the blending liquid in the blending unit, thereby further reducing the cost of the optimized system.

[0024] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0025] 1. This invention sets up a pretreatment unit connected to the flue and the water storage tank, mixing the flue gas and water and simultaneously blending them into an acid washing solution with suitable temperature and pH value through a blending unit. The biomass material is pretreated by the acid washing solution, reducing the ash content and metal elements in the biomass material. In this way, the amount of acid purchased can be reduced while achieving real-time control of the acid solution, enabling adaptive adjustment for different boiler combustion materials and biomass materials, saving costs and increasing the pretreatment effect.

[0026] 2. In this invention, the blending unit is equipped with baffles. When the blending unit blends the flue gas mixture, the baffles cause turbulence when the blending liquid in the blending tube enters the central tube, thereby accelerating the fusion of the blending liquid and the flue gas mixture. Since the temperature of the blending liquid is usually lower than that of the flue gas mixture, the angle of the baffles and their arrangement from top to bottom, gradually approaching the outer wall of the blending tube, result in a higher flow velocity of the blending liquid in the upper part of the blending tube. When the blending liquid enters the central tube, the higher-temperature flue gas mixture will convect upward with the blending liquid under the action of buoyancy and the blades, thereby further increasing the mixing rate and uniformity of the blending liquid and the flue gas mixture.

[0027] 3. This invention utilizes a central tube and an inner cylinder in conjunction. During the rotation of the central tube and inner cylinder driven by a differential speed motor, the central tube first sprays pickling solution onto the biomass material in the inner cylinder, thereby pre-treating the metal elements and ash content on the biomass material. Simultaneously, due to the differential rotation of the central tube and the inner cylinder, the pickling solution flows into the outer cylinder through centrifugal force when the inner cylinder rotates relative to the outer cylinder. During the spraying process, the impact force of the pickling solution on the biomass material is increased, thereby improving the efficiency of the pickling solution in carrying metal elements and ash. Under the centrifugal force, the biomass material forms a U-shaped surface, where the biomass material at higher horizontal heights has less material and requires less pickling solution. At the same time, the biomass material at higher horizontal heights comes into contact with less pickling solution and is more easily discharged through the separation hole, making the pickling of the biomass material more uniform and preventing excessive liquid residue on the biomass material after pickling. Attached Figure Description

[0028] Figure 1 This is a schematic diagram of the process of the present invention;

[0029] Figure 2 This is a schematic planar view of the preprocessing unit structure of the present invention;

[0030] Figure 3 This is a side view of the preprocessing unit structure of the present invention;

[0031] Figure 4 This is an exploded view of the pretreatment unit structure of the present invention;

[0032] Figure 5 This is a schematic diagram of the baffle structure of the present invention;

[0033] Figure 6 This is a cross-sectional view of the internal structure of the preprocessing unit of the present invention.

[0034] In the diagram: 100, Industrial kiln; 200, Primary waste heat treatment unit; 300, Secondary waste heat treatment unit; 400, Ceramic catalytic filtration unit; 500, Exhaust fan; 600, Chimney; 700, Pretreatment unit; 701, Outer cylinder; 702, Inner cylinder; 702a, Separation hole; 702b, Rotating shaft; 702c, Stirring plate; 703, Central tube; 703a, Blade; 703b, Through hole; 703c, Nozzle; 704, Differential motor; 705, Baffle plate; 705a, Top plate; 705b, Bottom plate; 705c, Corrugated plate; 800, Reagent addition unit; 900, Water storage tank; 1000, Blending unit; 1001, Blending equipment; 1002, Blending pipe. Detailed Implementation

[0035] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0036] Many specific details are set forth in the following description in order to provide a full understanding of the invention. However, the invention may also be practiced in other ways different from those described herein. Those skilled in the art can obtain other embodiments without departing from the spirit of the invention and without creative effort. Therefore, the invention is not limited to the specific embodiments disclosed below.

[0037] Please see Figures 1 to 6 This invention provides a dust removal and denitrification device for biomass boiler flue gas, the technical solution of which is as follows:

[0038] A biomass boiler flue gas dust removal and denitrification device includes an industrial kiln 100, a primary waste heat treatment unit 200, a secondary waste heat treatment unit 300, a ceramic catalytic filtration unit 400, an induced draft fan 500, a chimney 600, a pretreatment unit 700, a reactant addition unit 800, a water storage tank 900, and a blending unit 1000. The pretreatment unit 700 includes an outer cylinder 701, an inner cylinder 702, a central pipe 703, and a differential speed motor 704. The inner cylinder 702 includes a separation hole 702a, a rotating shaft 702b, and a stirring plate 702c. The central pipe 703 includes blades 703a, through holes 703b, and nozzles 703c. The baffle 705 includes a top plate 705a, a bottom plate 705b, and a corrugated plate 705c. The blending unit 1000 includes a blending device 1001 and a blending pipe 1002.

[0039] As one embodiment of the present invention, a biomass boiler flue gas dust removal and denitrification device includes an industrial kiln 100, a primary waste heat treatment unit 200, a secondary waste heat treatment unit 300, an induced draft fan 500, and a chimney 600, and also includes a pretreatment unit 700 and a reactant addition unit 800; the industrial kiln 100 is connected to the primary waste heat treatment unit 200 through a flue, the primary waste heat treatment unit 200 is connected to the pretreatment unit 700 through a flue, the pretreatment unit 700 is respectively connected to a water storage tank 900, a blending unit 1000, and a ceramic catalytic filter unit 400, the flue gas filtered by the ceramic catalytic filter unit 400 is discharged through the secondary waste heat treatment unit 300, the induced draft fan 500, and the chimney 600; the pretreatment unit 700 is connected to a water storage tank 900, a blending unit 1000, and a ceramic catalytic filter unit 400, the flue gas ... filtered by the ceramic catalytic filter unit 400, and the pretreatment unit 300 is connected to the secondary waste heat treatment unit 300, the induced draft fan 500, and the chimney 600; the pretreatment unit 700 is connected to a water storage tank 900, a blending unit 1000, and a ceramic catalytic filter unit 400, the pretreatment unit 700 is connected to a water storage tank 900, a blending unit 1000, and a ceramic cata The processing unit 700 includes an outer cylinder 701, an inner cylinder 702, a central tube 703, and a differential motor 704. The central tube 703 is connected to the flue of the primary waste heat treatment unit 200 and the water pipe of the water storage tank 900. The mixing pipe 1002 is set on the axis of the central tube 703. The central tube 703 sprays pickling solution into the inner cylinder 702. The differential motor 704 drives the central tube 703 and the inner cylinder 702 to rotate at different speeds. The flue gas and water are mixed through the pretreatment unit 700 connected to the flue and the water storage tank 900. The mixing unit 1000 mixes them into a pickling solution with suitable temperature and pH value. The pickling solution is sprayed into the inner cylinder 702 through the central tube 703 to pickle the biomass materials, thereby reducing ash and metal elements.

[0040] It should be noted that the reactant addition unit 800 is connected to the ceramic catalytic filtration unit 400, and the denitrification reducing agent is introduced through the existing SCR denitrification technology.

[0041] In one embodiment of the present invention, the central tube 703 is connected to the flue of the primary waste heat treatment unit 200 and the water pipe of the water storage tank 900, and is also connected to the mixing unit 1000 to spray the mixed pickling solution into the inner cylinder 702; the differential speed motor 704 drives the central tube 703 and the inner cylinder 702 to rotate at a different speed, so that the pickling solution and biomass material are mixed more evenly, and the impact force of the pickling solution is increased during the differential rotation, which promotes the cleaning and carrying of ash and metal elements on the biomass material.

[0042] In one embodiment of the present invention, a plurality of sets of separation holes 702a are uniformly arranged on the outer wall of the inner cylinder 702. A rotating shaft 702b is fixedly connected to the upper part of the inner cylinder 702, and an agitator 702c is provided at the bottom of the inner cylinder 702. The inner cylinder 702 is rotatably connected to the outer cylinder 701 and the central tube 703. The rotating shaft 702b is connected to the differential motor 704, and the agitator 702c is connected to the central tube 703. The diameter of the separation holes 702a gradually decreases from high to low. The rotating shaft 702b drives the inner cylinder 702 to rotate. The bottom of the outer cylinder 701 is connected to the waste liquid collection device. The agitator 702c agitates the bottom biomass material as the central tube 703 rotates, preventing the biomass material from settling at the bottom and being in contact with the flue gas mixture for too long.

[0043] It should be noted that the bottom of the outer cylinder 701 is connected to the waste liquid collection equipment using existing technology, and the outer cylinder 701 and the inner cylinder 702 are provided with an openable sealed opening on the same side. The flue of the primary waste heat treatment unit 200 and the water pipe of the water storage tank 900 pass through the outer cylinder 701 and are rotatably connected to the central pipe 703, and the rotatable part is sealed. The water volume of the water pipe is controlled by a water pump, and the flue is a branch flue of the primary waste heat treatment unit 200. When arranging, the balance between water pressure and flue pressure needs to be considered. The water pressure is adjusted adaptively after measuring the flue pressure. The flue gas and water will mix at the blade 703a to form a preliminary flue gas mixture.

[0044] The differential motor 704 drives the inner cylinder 702 and the central tube 703 to rotate at different speeds via the rotating shaft 702b. The pickling solution flows into the inner cylinder 702 through the central tube 703. During the rotation of the inner cylinder 702 relative to the outer cylinder 701, a certain amount of pickling solution remains at the bottom of the inner cylinder 702. The excess flue gas mixture flows into the outer cylinder 701 through the separation hole 702a under centrifugal force. The separation hole 702a, whose diameter gradually decreases from high to low, works in conjunction with the centrifugal force of the inner cylinder 702 to form a U-shaped surface of the biomass material under centrifugal force. The biomass material at the higher horizontal position has less material and requires less pickling solution. At the same time, the biomass material at the higher horizontal position comes into contact with less pickling solution and is more likely to be discharged through the separation hole, thus making the pickling more uniform, reducing liquid residue, and facilitating subsequent transportation and combustion.

[0045] It should be noted that the diameter of the separation hole 702a will not be larger than that of the biomass material. When using the differential motor 704, the speed can be gradually increased from a smaller speed. The differential motor 704 meshes with both the inner cylinder 702 and the central tube 703. The inner cylinder 702 and the central tube 703 rotate coaxially at different speeds. The central tube 703 maintains a sealed rotational connection when connected to other equipment. Under the centrifugal force of the inner cylinder 702, the biomass material will move towards the inner wall of the inner cylinder 702, and under the mutual compression of the biomass material, a U-shaped surface with a higher outer surface and a lower inner surface will be generated.

[0046] It should be noted that the differential motor 704 adopts existing technology. Specifically, the differential motor 704 can be equipped with a bevel gear on the drive shaft. The upper gear set meshes with the upper bevel gear, which meshes with the central tube 703 through a first gear. The lower bevel gear set meshes with a reduction gear set, which meshes with the rotating shaft 702b through a second gear, thereby achieving the effect of differential rotation between the rotating shaft 702b and the central tube 703. The differential motor 704 can adopt a single stator, with two independently controllable rotors meshing with the central tube 703 and the rotating shaft 702b respectively through two sets of gear sets, thereby achieving the effect of differential rotation between the central tube 703 and the rotating shaft 702b. The above embodiments are only used to illustrate the technical solution of the present invention so that those skilled in the art can understand and implement it, and are not intended to limit it. Those skilled in the art can make selections or equivalent substitutions according to actual needs.

[0047] As one embodiment of the present invention, the blending unit 1000 includes a blending device 1001 and a blending tube 1002; a blade 703a is provided at the bottom of the central tube 703, the blending tube 1002 is disposed inside the central tube 703, and a plurality of through holes 703b are uniformly disposed outside the central tube 703.

[0048] When the flue gas mixture is unstable, the blending equipment 1001 and the blending pipe 1002 transfer the blended liquid to the central pipe 703 to form an pickling solution that meets the preparation requirements. When the temperature of the flue gas cannot fully meet the requirements after passing through the primary waste heat treatment unit 200, the blending equipment 1001 simultaneously adjusts the temperature of the flue gas mixture so that the pH value and temperature of the pickling solution meet the preparation requirements.

[0049] In one embodiment of the present invention, a nozzle 703c is provided at the through hole 703b.

[0050] The nozzle 703c installed at the through hole 703b increases the flow rate of the pickling liquid when it flows out of the central tube 703 and disperses the pickling liquid to form a porous jet, so that it can contact the biomass material more evenly.

[0051] It should be noted that a detection and control module is installed at the top of the inner wall of the central tube 703. The detection and control module is connected to the nozzle 703c via a solenoid valve. The detection and control module is located above the set of baffles 705 at the highest horizontal height inside the central tube 703. It can detect the pH value and temperature of the pickling solution between the central tube 703 and the mixing tube 1002 through a combination of digital pH electrode sensors and temperature sensors. When the preparation standard is reached, the nozzle 703c is opened by the solenoid valve.

[0052] In one embodiment of the present invention, the outer wall of the mixing pipe 1002 is provided with a plurality of baffles 705. The baffles 705 are connected to the mixing pipe 1002 and are inclined on the outer side near the bottom. The baffles 705 include a top plate 705a, a bottom plate 705b disposed below the top plate 705a, and a plurality of wave plates 705c evenly distributed between the top plate 705a and the bottom plate 705b.

[0053] When the initial flue gas mixture is still above the optimal temperature after passing through the primary waste heat treatment unit 200, the blending liquid mixed with cold water flows through the blending pipe 1002, passes through the baffle 705, and enters the central pipe 703. The blending liquid generates turbulence under the obstruction of multiple sets of corrugated plates 705c, making the blending liquid and flue gas mixture more uniform.

[0054] In one embodiment of the present invention, the baffle 705 is arranged from top to bottom away from the axis of the mixing tube 1002 relative to the inner side of the mixing tube 1002; the baffles 705 on both sides can be staggered vertically.

[0055] The baffles 705 are staggered vertically to increase the tortuosity of the flow path of the blending liquid and enhance the turbulent mixing effect.

[0056] In one embodiment of the present invention, the inner side of the baffle 705 is configured as an inlet perpendicular to the wall of the mixing pipe 1002, and the top plate 705a, the wave plate 705c and the bottom plate 705b grow uniformly from top to bottom.

[0057] It should be noted that those skilled in the art can adjust the position of the baffle 705 according to the actual size and requirements. The baffle 705 and the mixing tube 1002 can be fixed after the position is adjusted.

[0058] The water flow gradually slows down in the structure that grows evenly from top to bottom. The high-temperature flue gas mixture entering from the bottom of the central tube 703 rises due to buoyancy and forms convection with the low-temperature blending liquid with a larger flow velocity in the upper part, increasing the mixing speed and uniformity of the pickling solution.

[0059] In one embodiment of the present invention, the tail liquid of the ceramic catalytic filtration unit 400 is collected, filtered, and then transferred to the blending device 1001.

[0060] The acidic tail liquid produced by the ceramic catalytic filtration unit 400 after catalysis is collected and filtered, and then used to modulate the blending liquid in the blending unit 1000, thereby reducing system costs.

[0061] Working principle: The flue gas discharged from the primary waste heat treatment unit 200 is connected to the central pipe 703. The flue gas mixes with the water in the water storage tank 900, which is also connected to the central pipe 703, to form a preliminary acidic flue gas mixture. At the same time, the mixing pipe 1002 determines the ratio of the mixing liquid according to the combustion material and biomass material of the industrial kiln 100. The mixing liquid is mixed with the flue gas mixture to form an pickling solution that meets the preparation requirements. The pickling solution is sprayed into the inner cylinder 702 through the central pipe 703 and comes into contact with the biomass material in the inner cylinder 702. At the same time, the inner cylinder 702 and the central pipe 703 rotate at different speeds. Excess pickling solution in the inner cylinder 702 flows into the outer cylinder 701 and is then discharged to the external waste liquid collection equipment.

[0062] Specifically, after combustion in the industrial kiln 100, the flue gas flows through the flue and then through the primary waste heat treatment unit 200 before connecting to the central pipe 703. It also passes through a water pipe in a water storage tank 900, which is simultaneously connected to the central pipe 703. The flue gas mixes with the water in the water pipe at the blade 703a. Under the action of the blade 703a, the flue gas and water form a preliminary flue gas mixture, which flows into the interlayer between the central pipe 703 and the blending pipe 1002. At this point, the flue gas mixture mixes with the blending liquid flowing out of the blending pipe 1002. The blending liquid flows through the baffle 705 and enters the central pipe 703. Passing through the corrugated plate 705c in the baffle 705, the blending liquid undergoes turbulence and merges with the flue gas mixture, improving efficiency. To achieve high fusion uniformity and accelerate the fusion rate, the baffle 705 is arranged obliquely with a higher inner horizontal height and a lower outer horizontal height, gradually moving outward from top to bottom. After the mixed liquid flows through the baffle 705, the flow velocity at the top will be greater than the flow velocity at the bottom due to the resistance of the baffle 705. Since the temperature of the flue gas mixture is usually higher than the required preparation temperature, the temperature of the mixed liquid needs to be lower than that of the flue gas mixture. At this time, the lower-temperature mixed liquid flows into the central pipe 703 from the top of the mixing pipe 1002 where the flow velocity is the maximum and begins to descend. At the same time, the flue gas mixture will float up under its own buoyancy and the action of the blades 703a, forming convection between the flue gas mixture and the mixed liquid, further improving the uniformity of the pickling solution.

[0063] The differential motor 704 drives the central tube 703 and the inner cylinder 702 to rotate at different speeds. At the same time, the central tube 703 sprays pickling solution into the inner cylinder 702 through the nozzle 703c. The pickling solution first falls to the bottom and reacts with the biomass material. As the central tube 703 and the inner cylinder 702 rotate, centrifugal force is generated. The centrifugal force of the rotating inner cylinder 702 will make some of the biomass material float upward and stick to the inner wall, thus dispersing the biomass material and reducing bottom sedimentation. Under the action of centrifugation, the biomass material will form a U-shaped surface. The biomass material at the higher horizontal position has less material and requires less pickling solution. At the same time, the biomass material at the higher horizontal position has less contact with pickling solution and is easier to discharge through the separation hole, making the pickling of biomass material more uniform. The pickling solution sprayed from the central tube 703 flows towards the inner wall of the inner cylinder 702 under the action of centrifugal force, flows towards the biomass material with greater impact force, and promotes the efficiency of carrying ash and metal elements when flowing out through the separation hole 702a.

[0064] It should be noted that before preparing the blending solution, the flue gas and flue gas mixture are sampled and measured. Based on the different pH values ​​and temperatures of the flue gas mixtures and the pH values ​​and temperatures of the pickling solutions required for different biomass materials, the proportion of the blending solution is pre-mixed.

[0065] The above embodiments are only used to illustrate some examples of the implementable technical solutions of the present invention and are not intended to limit the implementation. The present invention can be understood in more detail by referring to the embodiments. Those skilled in the art should understand that the technical solutions of the present invention can be modified or equivalently replaced without departing from the scope of the technical solutions of the present invention, and all such modifications and substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A biomass boiler flue gas dust removal and denitrification device, comprising an industrial kiln (100), a primary waste heat treatment unit (200), a secondary waste heat treatment unit (300), an induced draft fan (500), and a chimney (600), characterized in that: It also includes a pretreatment unit (700) and a reactant addition unit (800); the industrial kiln (100) is connected to the primary waste heat treatment unit (200) via a flue, the primary waste heat treatment unit (200) is connected to the pretreatment unit (700) via a flue, the pretreatment unit (700) is connected to a water storage tank (900), a blending unit (1000) and a ceramic catalytic filtration unit (400) respectively, the flue gas after filtration by the ceramic catalytic filtration unit (400) passes through the secondary waste heat treatment unit (300), the induced draft fan (500) and the chimney (600). 0) Discharge; The pretreatment unit (700) includes an outer cylinder (701), an inner cylinder (702), a central tube (703), and a differential motor (704); The central tube (703) is simultaneously connected to the flue of the primary waste heat treatment unit (200) and the water pipe of the water storage tank (900); The blending unit (1000) is located on the axis of the central tube (703); The central tube (703) sprays pickling liquid into the inner cylinder (702); The differential motor (704) drives the central tube (703) and the inner cylinder (702) to rotate at different speeds.

2. The biomass boiler flue gas dust removal and denitrification device according to claim 1, characterized in that: The inner cylinder (702) has several sets of separation holes (702a) evenly arranged on its outer wall; a rotating shaft (702b) is fixedly connected to the upper part of the inner cylinder (702); and a stirring plate (702c) is provided at the bottom of the inner cylinder (702). The inner cylinder (702) is rotatably connected to the outer cylinder (701) and the central tube (703); the rotating shaft (702b) is connected to the differential motor (704); and the stirring plate (702c) is connected to the central tube (703).

3. A biomass boiler flue gas dust removal and denitrification device according to claim 1 or 2, characterized in that: The blending unit (1000) includes a blending device (1001) and a blending tube (1002); the bottom of the central tube (703) is provided with a blade (703a), the blending tube (1002) is disposed inside the central tube (703), and a number of through holes (703b) are uniformly disposed outside the central tube (703).

4. The biomass boiler flue gas dust removal and denitrification device according to claim 3, characterized in that: A nozzle (703c) is provided at the through hole (703b).

5. The biomass boiler flue gas dust removal and denitrification device according to claim 3, characterized in that: The outer wall of the mixing pipe (1002) is provided with a number of baffles (705), the baffles (705) are connected to the mixing pipe (1002), and the baffles (705) are inclined on the outer side and close to the bottom. The baffles (705) include a top plate (705a), a bottom plate (705b) disposed below the top plate (705a), and a number of wave plates (705c) evenly distributed between the top plate (705a) and the bottom plate (705b).

6. The biomass boiler flue gas dust removal and denitrification device according to claim 5, characterized in that: The baffle (705) is arranged from top to bottom away from the axis of the central tube (703) relative to the inner side of the mixing tube (1002).

7. A biomass boiler flue gas dust removal and denitrification device according to claim 5 or 6, characterized in that: The inner side of the baffle (705) is configured as an inlet perpendicular to the wall of the mixing pipe (1002), and the top plate (705a), the wave plate (705c), and the bottom plate (705b) grow uniformly from top to bottom.

8. The biomass boiler flue gas dust removal and denitrification device according to claim 3, characterized in that: The tail liquid from the ceramic catalytic filtration unit (400) is collected, filtered, and then transferred to the blending device (1001).

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