A flue gas treatment system and a silicon industry new material production system

Abstract

The utility model discloses a flue gas treatment system and silicon industry new material production system belongs to the flue gas desulfurization and denitrification technology in silicon industry new material production process. The utility model discloses a waste heat boiler, dust collector and fixed bed dry method desulfurization and denitrification reactor, and the flue gas inlet of dust collector is connected the flue gas outlet of waste heat boiler, and the flue gas outlet of dust collector is connected fixed bed dry method desulfurization and denitrification reactor, and fixed bed dry method desulfurization and denitrification reactor includes the desulfurization bin and denitrification bin of horizontal distribution, and the flue gas enters from the front side and passes desulfurization bin and denitrification bin in proper order and discharges from the back side, and the upper end of desulfurization bin and denitrification bin is provided with the feed port respectively, and the lower end is provided with the discharge gate respectively. The utility model discloses can be low -cost reconstruction on the basis of existing system, and the desulfurization and denitrification are pollution -free and better, and the system maintenance cost is low, and by -product microsilica quality is better.

Description

Technical Field

[0001] This utility model relates to flue gas desulfurization and denitrification technology in the production process of new silicon materials, and particularly to a flue gas treatment system and a new silicon material production system. Background Technology

[0002] Combination Figure 1 Understanding: Silicon Industry New Materials refers to novel materials based on silicon. The primary target product of Silicon Industry New Materials production is industrial silicon, with microsilica powder as a byproduct. The main raw materials for producing Silicon Industry New Materials include silica, washed coal, and wood blocks. The production process can be divided into batching (achieved in a batching system), smelting (achieved in a submerged arc furnace), refining, and finished product processing (see...). Figure 1 The stages include pouring, cooling and subsequent processes, and flue gas treatment (treating the flue gas generated in the electric arc furnace, refining and pouring process); Figure 1 Although the diagram does not fully illustrate all the production equipment, the main equipment and facilities include an electric arc furnace production line, supporting waste heat utilization power generation equipment, waste heat recovery system, oxygen refining system, and supporting flue gas dust removal and microsilicon powder densification system.

[0003] In the flue gas treatment stage, the temperature of the flue gas from the electric arc furnace is generally between 450-650 degrees Celsius. After heat recovery by the waste heat boiler, it undergoes desulfurization, dust removal, and denitrification treatment before being discharged into the atmosphere. Depending on the material characteristics and combustion conditions, the basic pollutant content in the flue gas includes: particulate matter concentration of 3000 mg / m³. 3 Around 1000 mg / m² 3 -3000mg / m 3 Between; sulfide concentrations between 100 mg / m³ 3 -150mg / m 3 Approximately; nitrogen oxide concentration around 200 mg / m³ 3 Left and right. For example... Figure 1As shown, existing flue gas desulfurization and denitrification technologies involve directly injecting powdered materials (such as baking soda or calcium-based ultrafine powder) into the flue gas duct for dry desulfurization, thereby removing sulfides. Then, dust is removed using bag filters or other equipment, and the flue gas after dust removal is denitrified using SCR (Sequencing and Catalytic Reduction). However, existing technologies have several problems: First, the desulfurization efficiency is low. This is because the particulate matter concentration in the flue gas from submerged arc furnaces is already high. Injecting powdered materials reduces the efficiency of the desulfurizing agent's contact with the flue gas, thus significantly reducing the desulfurization effect of the powdered materials. This ultimately leads to a high calcium-to-sulfur ratio or sodium-to-sulfur ratio, increasing operating costs and potentially causing environmental standards to be exceeded. Second, bag filters separate microsilica powder, a major byproduct of industrial silicon production lines. However, the addition of baking soda and calcium-based ultrafine powder during desulfurization increases the impurity content in the dust, affecting the quality and purity of the microsilica powder. Third, SCR denitrification uses ammonia as a reducing agent. Ammonia is a chemical, and its transportation and storage requirements are high. Even if urea is used, a series of facilities such as a dissolution tank are required. The overall management and safety on site are quite complex. At the same time, the use of ammonia or urea has the problem of ammonia escape, which has never been solved. Furthermore, the denitrification catalyst is a hazardous waste, with high treatment costs, which is also detrimental to environmental protection. Fourth, the powder conveying system and the dust conveying system are prone to clogging. Related equipment and denitrification system equipment require regular inspection and maintenance, and additional workers are needed. The management and maintenance of the entire system are quite complex and cumbersome.

[0004] Addressing the problems exposed in stages such as flue gas treatment is imperative, but dismantling the entire original flue gas treatment system and redesigning and rebuilding it is too costly. Therefore, this utility model proposes a flue gas treatment system that can be implemented with low cost based on existing technology. Utility Model Content

[0005] The purpose of this invention is to provide a flue gas treatment system that can be implemented at low cost by modifying existing silicon new material production systems.

[0006] The technical solution of this utility model is as follows:

[0007] A flue gas treatment system for the production of new silicon materials includes a waste heat boiler, a dust removal device, and a fixed-bed dry desulfurization and denitrification reactor. The flue gas inlet of the dust removal device is connected to the flue gas outlet of the waste heat boiler, and the flue gas outlet of the dust removal device is connected to the fixed-bed dry desulfurization and denitrification reactor. The fixed-bed dry desulfurization and denitrification reactor includes horizontally distributed desulfurization chambers and denitrification chambers. Flue gas enters from the front and passes through the desulfurization chamber and the denitrification chamber in sequence before being discharged from the rear. The upper end of the desulfurization chamber and the denitrification chamber are respectively provided with a feed inlet, and the lower end is respectively provided with a discharge outlet.

[0008] As an alternative, the dust removal device includes a bag filter.

[0009] As an alternative, the fixed-bed dry desulfurization and denitrification reactor includes a shell and a porous baffle device. The periphery of the porous baffle device is connected to the inner wall of the shell, and the desulfurization chamber and the denitrification chamber are separated within the shell.

[0010] As an alternative, the interior of the shell is divided into three compartments by two porous partitions, at least one of which is used as the desulfurization compartment; or, the interior of the shell is divided into four compartments by three porous partitions, two of which are used as the desulfurization compartments.

[0011] As an alternative, the porous partition device includes a porous plate and a support frame that are stacked and fixedly connected, with the edges of the porous plate and the support frame connected to the inner wall of the housing.

[0012] As an alternative, the porosity of the perforated plate gradually decreases from top to bottom; and / or, the perforated baffle device is vertically arranged and perpendicular to the flow direction of the flue gas.

[0013] As an alternative, the thickness of the desulfurization chamber is the same as the thickness of the denitrification chamber in the direction of flue gas flow.

[0014] As an optional solution, the fixed-bed dry desulfurization and denitrification reactor includes two sets of airflow inlet and outlet devices. Each airflow inlet and outlet device includes a U-shaped airflow pipe and a horn-shaped component. The airflow pipe has a flue gas inlet and outlet in the middle, and each of the two ports is connected to a narrow opening of the horn-shaped component. The wide opening of the horn-shaped component is fixedly connected to the shell. The wide openings of the two horn-shaped components on the same side cover the effective reaction area of ​​the desulfurization chamber or denitrification chamber.

[0015] As an alternative, the airflow inlet / outlet device located on the front side further includes an airflow distribution component disposed between the narrow and wide openings of the horn component. The periphery of the airflow distribution component is fixed to the inner surface of the horn component. The airflow distribution component includes a distribution grid and several guide plates. The holes of the distribution grid are horizontally arranged, and the guide plates are distributed vertically and divergingly. The guide plates divide the flue gas into several streams of airflow and evenly guide the several streams of airflow to various areas of the wide opening of the horn component.

[0016] As an optional solution, the flue gas treatment system also includes a conveyor scraper conveyor located below the desulfurization chamber and the denitrification chamber, for receiving waste materials discharged from the desulfurization chamber and the denitrification chamber.

[0017] A new silicon material production system includes a batching system, a submerged arc furnace, a refining system, and a casting system connected in sequence, and also includes a flue gas treatment system as described in any one of the above. The flue gas outlet of the submerged arc furnace is connected to the waste heat boiler, and the flue gas outlets of the refining system and the casting system are respectively connected to the flue gas inlet of the dust removal device.

[0018] This utility model has at least the following beneficial effects:

[0019] First, based on existing technology, the dry desulfurization and denitrification equipment is dismantled, and a fixed-bed dry desulfurization and denitrification reactor is installed at the original denitrification equipment location. The flue gas outlet of the waste heat boiler is connected to the flue gas inlet of the dust removal device, and the flue gas outlet of the dust removal device is connected to the fixed-bed dry desulfurization and denitrification reactor. This completes the transformation of the existing system. It can be seen that the transformation space does not require major adjustments, the required equipment is not large, and there is no impact on equipment outside the flue gas treatment system. Therefore, the transformation cost is very small.

[0020] Secondly, by eliminating the step of spraying powdered materials such as baking soda or calcium-based ultrafine powder for desulfurization in the existing process before the dust removal device, the dust removal device can be used entirely for collecting microsilica powder. This avoids problems such as insufficient purity of microsilica powder, reduced added value, and economic losses due to the addition of desulfurizing agents. In addition, since the desulfurization and denitrification steps are located after the dust removal device, the quality and purity of microsilica powder are not affected by the desulfurization and denitrification steps.

[0021] Third, after eliminating the original SCR denitrification, there is no longer a need for ammonia / urea transportation devices. Problems such as high safety requirements for ammonia / urea transportation and storage, and cumbersome operation no longer exist. The problem of hazardous waste from denitrification catalysts no longer exists, and the problem of ammonia escape also no longer exists.

[0022] Fourth, the flue gas is first dusted, and then desulfurized and denitrified. After dust removal, the particulate matter concentration in the flue gas is significantly reduced, which solves the problem that the high particulate matter concentration in the original flue gas has a negative impact on the desulfurization effect.

[0023] Fifth, regardless of whether it is a desulfurizing agent or a denitrifying agent, the by-products are all solid wastes. Suppliers can also provide a series of services such as by-product recycling and maintenance, which reduces maintenance costs.

[0024] Sixth, the desulfurizing and denitrifying agents used in fixed-bed dry desulfurization and denitrification technology are solid particles. That is, the desulfurization and denitrification chambers are filled with granular materials. These materials themselves have an adsorption and filtration effect on particles in flue gas, resulting in a lower content of particulate matter in the final discharged flue gas, thus making it more environmentally friendly.

[0025] Seventh, the desulfurization and denitrification chambers are arranged horizontally and are independent of each other. Multiple chambers of each type can be set up. Sufficient number of desulfurization and denitrification chambers should be reserved in advance. When the flue gas volume, sulfide and nitrogen oxide concentration fluctuate, the number of layers of desulfurizing agent and denitrifying agent can be adjusted at any time. In addition, when the desulfurizing agent reaches the end of its life, only the material in the desulfurization chamber needs to be replaced. The replacement of the material in the denitrification chamber is the same.

[0026] Eighth, desulfurization and denitrification during horizontal flue gas flow reduces the probability of uneven reaction of desulfurizing or denitrifying agents in different parts of the storage chamber compared to desulfurization and denitrification during vertical flow.

[0027] Ninth, the desulfurization chamber and the denitrification chamber are relatively independent, and both are fed from the top and discharged from the bottom, making it convenient to change materials. Attached Figure Description

[0028] The technical features and advantages of this utility model can be more fully understood by taking into account the accompanying drawings and the following detailed description.

[0029] Figure 1 This is a flowchart of the production process for new silicon materials in the prior art.

[0030] Figure 2 This is a production process flow diagram of the new silicon material according to an embodiment of this utility model.

[0031] Figure 3 This is a cross-sectional schematic diagram of a fixed-bed dry desulfurization and denitrification reactor according to an embodiment of the present invention, used to illustrate the overall structure and working principle of the fixed-bed dry desulfurization and denitrification reactor.

[0032] Figure 4 This is a schematic diagram of the porous partition device according to an embodiment of the present invention. When fully displayed, the porous plate and the support frame appear slender from this perspective, so only one section is shown.

[0033] Figure 5 This is a schematic diagram of the airflow distribution component according to an embodiment of the present invention.

[0034] Figure label:

[0035] 1. Shell; 11. Desulfurization chamber; 12. Denitrification chamber; 2. Perforated baffle device; 21. Perforated plate; 22. Support frame; 3. Manual slide gate; 4. Rotary rotary valve; 5. Airflow inlet / outlet device; 51. Airflow duct; 52. Horn component; 53. Flue gas inlet / outlet; 54. Airflow distribution assembly; 55. Distribution grid; 56. Guide plate; 57. Connecting plate; 6. Conveying scraper conveyor. Detailed Implementation

[0036] Unless otherwise defined, the technical or scientific terms used in this specification and claims shall have the ordinary meaning as understood by one of ordinary skill in the art to which this utility model pertains.

[0037] Before going into detail, let's explain some information in the accompanying diagram. This is for your convenience. Figure 3 This diagram illustrates the working principle of a fixed-bed dry desulfurization and denitrification reactor. Arrows indicate the directions of flue gas and materials, and the terms "Flue Gas Direction" and "Material Flow Direction" are labeled accordingly. To demonstrate the relationship between the airflow distribution component, the horn-shaped component 52, and the flue gas, Figure 5 The diagram illustrates the direction of the flue gas and is labeled with the words "Flue Gas Direction".

[0038] Combination Figure 2-5 Understanding. This utility model embodiment provides a silicon industry new material production system for producing silicon industry new materials. The system feeds raw materials such as washed silica, washed coal, and wood blocks into a batching system. The flue gas generated in the batching system enters the electric arc furnace after passing through a bag filter. Other products also enter the electric arc furnace. The flue gas generated during the processing in the electric arc furnace enters the flue gas treatment system. Other products enter the refining stage to extract silicon. The flue gas generated in the refining stage also enters the flue gas treatment system. Other products are further cast and cooled, and then processed in two paths. One path is crushed and packaged to obtain industrial silicon, while the other path passes through a jaw crusher, a main crusher, and a square screen to obtain silicon powder or fine powder. The flue gas treatment system performs waste heat recovery, separation of micro silicon powder, and desulfurization and denitrification treatment on the flue gas. The obtained micro silicon powder is further densified and then packaged.

[0039] The flue gas treatment system includes a waste heat boiler, a dust removal device, and a fixed-bed dry desulfurization and denitrification reactor. The waste heat boiler is connected to the exhaust port of the electric arc furnace, and it recovers waste heat from the flue gas to generate electricity. The dust removal device's inlet is connected to the exhaust port of the waste heat boiler to receive the flue gas discharged from it. Additionally, the dust removal device's inlet is also connected to equipment in the refining and casting processes. The dust removal device's exhaust port is connected to the fixed-bed dry desulfurization and denitrification reactor, where it performs gas-solid separation on the flue gas. The separated solids are microsilica powder, while the gaseous gases enter the fixed-bed dry desulfurization and denitrification reactor. The fixed-bed dry desulfurization and denitrification reactor includes horizontally distributed desulfurization chamber 11 and denitrification chamber 12. Flue gas enters from the front of the reactor and passes through desulfurization chamber 11 and denitrification chamber 12 in sequence before exiting from the rear. The upper ends of desulfurization chamber 11 and denitrification chamber 12 are respectively equipped with feed inlets, and the lower ends are respectively equipped with discharge outlets. Desulfurization chamber 11 is used to fill with desulfurizing agent granules, and denitrification chamber 12 is used to fill with denitrification agent granules. Both desulfurizing and denitrification agent granules are introduced from the top of their respective chambers and discharged from the bottom after the reaction reaches a certain stage. There are pores between desulfurization chamber 11 and denitrification chamber 12 to facilitate flue gas flow. Furthermore, "front" and "rear" here indicate the relative positions of flue gas inflow and outflow, meaning the flue gas flows horizontally rather than vertically. "Front" and "rear" can also be represented by "left" and "right."

[0040] Therefore, it can be seen that this utility model has at least the following advantages: First, compared with... Figure 1 and Figure 2Understanding this, based on existing technology, the dry desulfurization and denitrification equipment is dismantled, and a fixed-bed dry desulfurization and denitrification reactor is installed at the original denitrification equipment location. The flue gas outlet of the waste heat boiler is connected to the flue gas inlet of the dust removal device, and the flue gas outlet of the dust removal device is connected to the fixed-bed dry desulfurization and denitrification reactor. This completes the modification of the existing system. It is evident that the modification requires minimal space adjustments, few equipment upgrades, and has no impact on equipment outside the flue gas treatment system, thus resulting in very low modification costs. Secondly, this invention eliminates the step of injecting powdered materials such as baking soda or calcium-based ultrafine powder for desulfurization before the dust removal device in the existing process flow. Therefore, the dust removal device can be used entirely for collecting microsilica powder, avoiding problems such as insufficient purity, reduced added value, and economic losses due to the addition of desulfurizing agents. Furthermore, since the desulfurization and denitrification stages are located after the dust removal device, the quality and purity of the microsilica powder are unaffected by these stages. Third, by eliminating the original SCR denitrification, ammonia / urea transportation devices are no longer needed. Problems such as high safety requirements for ammonia / urea transportation and storage, and cumbersome operation are eliminated. The issue of hazardous waste from the denitrification catalyst is also eliminated, as is the problem of ammonia escape. Fourth, by first removing dust from the flue gas, followed by desulfurization and denitrification, the particulate matter concentration in the flue gas after dust removal is significantly reduced, solving the problem of the high particulate matter concentration in the original flue gas negatively impacting the desulfurization effect. Fifth, in this invention, both the desulfurizing agent and the denitrification agent produce solid waste as byproducts. Suppliers can also provide a series of services such as byproduct recycling and maintenance, reducing maintenance costs. Sixth, the desulfurizing and denitrification agents used in the fixed-bed dry desulfurization and denitrification technology are solid particles. That is, the desulfurization chamber 11 and the denitrification chamber 12 are filled with granular materials. These materials themselves have an adsorption and filtration effect on particles in the flue gas, resulting in a lower particulate matter content in the final discharged flue gas, thus making it more environmentally friendly. Seventh, the desulfurization chamber 11 and denitrification chamber 12 are arranged horizontally and are independent of each other. Multiple chambers of each type can be set up, with sufficient number of chambers 11 and 12 pre-reserved. When the flue gas volume, sulfide, and nitrogen oxide concentrations fluctuate, the number of layers of desulfurizing and denitrifying agents can be adjusted at any time. In addition, when the desulfurizing agent reaches the end of its lifespan, only the material in the desulfurization chamber 11 needs to be replaced, and the replacement of the material in the denitrification chamber 12 is the same. Eighth, desulfurization and denitrification during horizontal flue gas flow reduces the probability of significant uneven reactions of desulfurizing or denitrifying agents in different parts of the chambers compared to desulfurization and denitrification during vertical flow. Ninth, the desulfurization chamber 11 and denitrification chamber 12 are relatively independent, and both are fed from the top and discharged from the bottom, making material replacement more convenient.

[0041] The following section will elaborate on each part of the flue gas treatment system.

[0042] Dust removal equipment includes bag filters, which are commonly used in existing silicon new material production systems. They can be retained during the renovation, and the connection between the bag filters and refining and casting equipment does not need to be changed, thus reducing renovation costs.

[0043] A fixed-bed dry desulfurization and denitrification reactor can be a calcium-based fixed bed, meaning the material in the desulfurization chamber uses a calcium-based desulfurizing agent. The fixed-bed dry desulfurization and denitrification reactor includes a shell 1 and a porous baffle device 2. The areas on the shell 1 used for flue gas inlet and outlet are designed with a porous structure, while other areas prevent flue gas leakage. The periphery of the porous baffle device 2 is connected to the inner wall of the shell 1, and it isolates the desulfurization chamber 11 and the denitrification chamber 12 within the shell 1.

[0044] Because the characteristics of flue gas from different furnaces vary, including flow rate, sulfide content, nitrogen oxide concentration, and permissible emission standards, the number and size of desulfurization chambers 11 and denitrification chambers 12 differ across projects. The length and height of the chambers can be determined based on the flue gas velocity (typically 0.3 m / s-0.5 m / s), while the number of chambers and the material layer thickness are determined based on the permissible system resistance and refueling cycle. The number of porous baffle devices 2 can be set according to the required number of desulfurization chambers 11 and denitrification chambers 12. Figure 3 In the illustrated embodiment, the interior of the shell 1 is divided into four side-by-side compartments by three porous partitions 2, two of which are used as desulfurization compartments 11 and the other two as denitrification compartments 12; in other embodiments, the interior of the shell 1 can also be divided into three compartments by two porous partitions 2, one of which is used as a desulfurization compartment 11 and the other two as denitrification compartments 12, or one of which is used as a denitrification compartment 12 and the other two as desulfurization compartments 11.

[0045] The porous baffle device 2 includes a porous plate 21 stacked and fixedly connected front to back, and a support frame 22, which can be welded together. In some embodiments, porous plates 21 are respectively provided on both sides of the support frame 22, but as an alternative, porous plates 21 can be provided on only one side of the support frame 22. In some embodiments, the thickness of the desulfurization chamber 11 and the thickness of the denitrification chamber 12 are the same in the direction of flue gas flow, that is, the porous baffle devices 2 are evenly distributed.

[0046] The perforated plate 21 is a plate with numerous pores for flue gas flow. The perforated plate 21 is a 3-5mm thick steel plate made of 304 or 316L stainless steel with elongated holes, and the opening ratio is between 30% and 60%, the specific value determined by resistance and air velocity. Simultaneously, considering the different material bulk densities and the upward movement of hot gas along the height direction, the opening ratio gradually decreases from bottom to top. Furthermore, the size of the pores on the perforated plate is insufficient for the desulfurizing and denitrifying agents to pass through; that is, the perforated plate 21 also serves to block the desulfurizing and denitrifying agents. The perforated baffle device 2 is preferably vertically installed, perpendicular to the flue gas flow direction, so that when the desulfurizing and denitrifying agents are discharged, the material falls under the influence of gravity and does not remain on the perforated plate 21, thus preventing easy clogging of the pores.

[0047] The periphery of the support frame 22 is fixed inside the shell 1. The support frame 22 serves to fix and support the perforated plate 21. It can adopt a structure similar to steel grating. The thickness, height, spacing and other data of the stiffeners are calculated according to the load data.

[0048] Additionally, inside the shell 1, the discharge ports of the desulfurization chamber 11 and the denitrification chamber 12 are funnel-shaped to facilitate material unloading. Each discharge port is equipped with a manual gate valve 3 and a rotary valve 4; these valves are opened during unloading. A conveyor scraper conveyor 6 is installed below the desulfurization chamber 11 and the denitrification chamber 12 to receive waste materials discharged from them.

[0049] The fixed-bed dry desulfurization and denitrification reactor also includes two sets of airflow inlet / outlet devices 5. One set supplies flue gas into the desulfurization chamber 11, and the other set supplies flue gas out of the denitrification chamber 12. The airflow inlet / outlet device 5 includes a U-shaped airflow pipe 51 and a horn-shaped component 52. A flue gas inlet / outlet 53 is located in the middle of the airflow pipe 51, and each of the two ends is connected to the narrow opening of a horn-shaped component 52. The wide opening of the horn-shaped component 52 is fixedly connected to the shell 1. Flue gas discharged from the waste heat boiler enters through the flue gas inlet / outlet 53 on the desulfurization chamber 11 side, and then enters the two horn-shaped components 52 through the airflow pipe 51. After a brief buffering process within the horn-shaped components 52, the flue gas sequentially enters the desulfurization chamber 11 and the denitrification chamber 12, and then exits from the airflow inlet / outlet device 5 on the denitrification chamber 12 side.

[0050] The wide openings of the two horn-shaped components 52 on the same side cover the effective reaction area of ​​the desulfurization chamber 11 or the denitrification chamber 12. The effective reaction area is the area filled with material of uniform thickness, for example... Figure 3In the desulfurization chamber 11, the material is uniformly thick in a straight cylindrical section and a conical section at the bottom. The material thickness in the straight cylindrical section is uniform, thus the straight cylindrical sections in the front and rear chambers correspond to the effective reaction zone. The conical section is for easy material discharge and is therefore unrelated to the effective reaction zone. Flue gas enters the desulfurization chamber 11 from the effective reaction zone and reacts with the desulfurizing agent. Similarly, on one side of the denitrification chamber 12, flue gas flows out of the effective reaction zone and immediately enters the horn-shaped component 52. With this design, the desulfurizing agent reaction is relatively uniform throughout the same desulfurization chamber 11, and the reaction in different desulfurization chambers 11 is also relatively synchronous. The same applies to the denitrification chamber 12. Furthermore… Figure 3 In the embodiment shown, the two horn members 52 on the same side are arranged vertically, each covering half of the effective reaction area. As an alternative, the other two horn members 52 on the same side can also be arranged horizontally, each covering half of the effective reaction area.

[0051] The structure at the effective reaction area of ​​the shell 1 can adopt the aforementioned porous partition device 2. For example, the main structure of the shell 1 has an opening at the position corresponding to the effective reaction area, and the support frame 22 in the porous partition device 2 at that position is fixed to the edge of the opening.

[0052] The airflow inlet and outlet device 5 located on the air inlet side also includes an airflow equalization component 54, which is set between the narrow opening and the wide opening of the horn component 52. The periphery of the airflow equalization component 54 is fixed to the inner surface of the horn component 52. It is used to control the flue gas flow to different positions in the desulfurization chamber 11, so that there is flue gas in each position of the desulfurization chamber 11 in the height direction, preventing the flow deviation phenomenon, thereby ensuring that the material reaction in different areas of the desulfurization chamber 11 and the denitrification chamber 12 is relatively balanced.

[0053] The airflow distribution assembly 54 includes a distribution grid 55 and several guide plates 56. The distribution grid 55 includes several fixedly connected plates. The holes of the distribution grid 55 are horizontally arranged, which enables the flue gas entering the horn member 52 to flow horizontally quickly and prevents the flue gas from forming several small airflow vortices in the horn member 52 and causing flow deviation.

[0054] The guide vanes 56 are distributed in a divergent pattern, with each vane positioned vertically. They are used to disperse the flue gas flowing in from the uniform grid 55 to various areas at the wide opening of the horn-shaped component 52. Specifically, one end of each guide vane 56 is directly fixed to the uniform grid 55, or fixed to the horn-shaped component 52 or the uniform grid 55 via a connecting plate 57, or directly fixed to the inner wall of the horn-shaped component 52 via a connecting plate 57. This connecting plate 57 does not obstruct the flue gas flowing in from the uniform grid 55. The other end of each guide vane 56 extends towards the wide opening of the horn-shaped component 52, dividing the flue gas into several streams and evenly guiding these streams to various areas at the wide opening of the horn-shaped component 52. This achieves comprehensive and effective utilization of the desulfurizing agent and denitrifying agent, preventing issues such as flow deviation and premature material penetration in certain areas.

[0055] It will be apparent to those skilled in the art that this invention is not limited to the details of the exemplary embodiments described above, and that it can be implemented in other specific forms without departing from the spirit or essential characteristics of this invention. Therefore, the embodiments should be considered illustrative and non-limiting in all respects, and the scope of this invention is defined by the appended claims rather than the foregoing description. Thus, it is intended that all variations falling within the meaning and scope of equivalents of the claims be included within this invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

Claims

1. A flue gas treatment system, characterized in that, The system includes a waste heat boiler, a dust removal device, and a fixed-bed dry desulfurization and denitrification reactor. The flue gas inlet of the dust removal device is connected to the flue gas outlet of the waste heat boiler, and the flue gas outlet of the dust removal device is connected to the fixed-bed dry desulfurization and denitrification reactor. The fixed-bed dry desulfurization and denitrification reactor includes horizontally distributed desulfurization chambers and denitrification chambers. Flue gas enters from the front and passes through the desulfurization chamber and the denitrification chamber in sequence before being discharged from the rear. The upper end of the desulfurization chamber and the denitrification chamber are respectively provided with a feed inlet, and the lower end is respectively provided with a discharge outlet.

2. The flue gas treatment system according to claim 1, characterized in that, The fixed-bed dry desulfurization and denitrification reactor includes a shell and a porous baffle device. The periphery of the porous baffle device is connected to the inner wall of the shell, and the desulfurization chamber and the denitrification chamber are separated within the shell.

3. The flue gas treatment system according to claim 2, characterized in that, The interior of the shell is divided into three compartments by two porous partitions, at least one of which is used as the desulfurization compartment; or, the interior of the shell is divided into four compartments by three porous partitions, two of which are used as the desulfurization compartments.

4. The flue gas treatment system according to claim 2, characterized in that, The porous partition device includes a porous plate and a support frame that are stacked and fixedly connected, with the edges of the porous plate and the support frame connected to the inner wall of the housing.

5. The flue gas treatment system according to claim 4, characterized in that, The perforation rate of the perforated plate gradually decreases from top to bottom; and / or, the perforated baffle device is vertically arranged and perpendicular to the flue gas flow direction.

6. The flue gas treatment system according to claim 2, characterized in that, In the direction of flue gas flow, the thickness of the desulfurization chamber is the same as the thickness of the denitrification chamber.

7. The flue gas treatment system according to claim 2, characterized in that, The fixed-bed dry desulfurization and denitrification reactor includes two sets of airflow inlet and outlet devices. Each airflow inlet and outlet device includes a U-shaped airflow pipe and a horn-shaped component. The airflow pipe has a flue gas inlet and outlet in the middle, and each of the two ports is connected to a narrow opening of the horn-shaped component. The wide opening of the horn-shaped component is fixedly connected to the shell. The wide openings of the two horn-shaped components on the same side cover the effective reaction area of ​​the desulfurization chamber or denitrification chamber.

8. The flue gas treatment system according to claim 7, characterized in that, The airflow inlet and outlet device located on the front side also includes an airflow equalization component disposed between the narrow opening and the wide opening of the horn component. The periphery of the airflow equalization component is fixed to the inner surface of the horn component. The airflow equalization component includes an equalization grid and several guide plates. The holes of the equalization grid are horizontally arranged. Each of the guide plates is distributed vertically and diverges outward. The guide plates divide the flue gas into several streams of airflow and evenly guide the several streams of airflow to various areas of the wide opening of the horn component.

9. The flue gas treatment system according to any one of claims 1-8, characterized in that, The flue gas treatment system also includes a conveyor scraper conveyor located below the desulfurization chamber and the denitrification chamber, used to receive waste materials discharged from the desulfurization chamber and the denitrification chamber.

10. A new silicon material production system, characterized in that, The system includes a batching system, an electric arc furnace, a refining system, and a casting system connected in sequence, and also includes the flue gas treatment system according to any one of claims 1-9, wherein the flue gas outlet of the electric arc furnace is connected to the waste heat boiler, and the flue gas outlets of the refining system and the casting system are respectively connected to the flue gas inlet of the dust removal device.

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