Industrial silicon smelting flue gas treatment system

Abstract

The utility model discloses an industrial silicon smelting flue gas treatment system, which aims to solve the technical problem that an industrial silicon smelting furnace is forced to be shut down when a first waste heat boiler unit is shut down. Comprising the following parts: a first waste heat recovery unit, which is used for receiving industrial silicon furnace smelting flue gas discharged by an industrial silicon smelting furnace, carrying out first waste heat recovery and utilization, and outputting first cooled flue gas with the temperature reduced to 180-450 DEG C; a flue gas filtering dust remover unit and an SCR denitration reactor unit; a first pipeline connected with the first waste heat recovery unit in parallel is arranged beside the first waste heat recovery unit, a second pipeline is connected to the first pipeline, valves are arranged at an inlet of the first pipeline, an inlet of the first waste heat recovery unit and an inlet of the second pipeline, and a cooling gas inlet device is connected to an inlet of the second pipeline. Even if the first waste heat boiler unit is shut down, the industrial silicon smelting flue gas treatment system can still work continuously, so that the industrial silicon smelting furnace is prevented from being shut down.

Description

Technical Field

[0001] The present disclosure relates to the technical field of industrial silicon smelting flue gas treatment, and in particular to an industrial silicon smelting flue gas treatment system. The present disclosure also relates to an integrated dust removal and denitrification device that can be used in the above industrial silicon smelting flue gas treatment system. Background Art

[0002] The applicant provides an industrial silicon smelting flue gas treatment system in the patent document with publication number CN114887409A, which first adjusts the industrial silicon smelting furnace smelting flue gas with a temperature of 450℃-650℃ discharged from the industrial silicon smelting furnace to a first cooled flue gas with a temperature of 300℃-450℃ through a first waste heat boiler unit, and then adjusts the first cooled flue gas to dust-removed flue gas after filtering and dust-removing the first cooled flue gas through a flue gas filter dust collector unit, and then denitrates the dust-removed flue gas through an SCR denitrification reactor unit to obtain denitrified flue gas, and then adjusts the denitrified flue gas to a second cooled flue gas with a temperature of 100℃-200℃ through a second waste heat boiler unit, and the second cooled flue gas finally enters a desulfurization device for desulfurization. The actual problems of the industrial silicon smelting flue gas treatment system are as follows: First, the desulfurization device is set after the second waste heat boiler unit, and currently dry desulfurization is usually selected for environmental protection considerations. Since the tail gas after dry desulfurization will be mixed with a certain concentration of particulate matter (particulate matter includes residual desulfurizer and the reactants of desulfurizer and sulfur dioxide), it is necessary to set up dust removal equipment after the desulfurization device, which further increases the construction and use costs of the industrial silicon smelting flue gas treatment system. Second, the working conditions of the first waste heat boiler unit are relatively poor. Specifically, the industrial silicon smelting furnace smelting flue gas received by the first waste heat boiler unit has a high temperature and a large dust concentration. When the first waste heat boiler unit is shut down for maintenance and other reasons, the industrial silicon smelting furnace is also forced to shut down, affecting production.

[0003] The applicant provides an industrial silicon smelting flue gas treatment system in the patent document with publication number CN218011732U, which adjusts the flue gas desulfurization unit to be deployed between the first waste heat boiler unit and the flue gas filter dust collector unit, so that the particulate matter mixed in the flue gas after desulfurization is filtered out by the flue gas filter dust collector unit. However, the industrial silicon smelting flue gas treatment system has such a problem that after the flue gas desulfurization unit is adjusted and deployed between the first waste heat boiler unit and the flue gas filter dust collector unit, the dust concentration in the flue gas entering the flue gas filter dust collector unit is further increased, thereby increasing the workload of the flue gas filter dust collector unit. Therefore, in practice, the applicant has added a mechanical dust collector (cyclone dust collector) between the flue gas desulfurization unit and the flue gas filter dust collector unit, and according to convention, the dust recovered by the mechanical dust collector is returned to the flue gas desulfurization unit to realize the recycling of the desulfurizer. However, practice shows that this method cannot effectively improve the problem of heavy workload of the flue gas filter dust collector unit.

[0004] On the other hand, the applicant also adopted a dust removal and denitrification integrated device in the above-mentioned industrial silicon smelting flue gas treatment system, which is formed by assembling the SCR denitrification reactor unit on the flue gas filtering and dust removal unit. The dust removal and denitrification integrated device combines two devices into one, which greatly saves the construction land of the industrial silicon smelting flue gas treatment system. However, the structural design of the dust removal and denitrification integrated device currently adopted is still not reasonable enough, mainly reflected in: first, the specific structure of the dust removal and denitrification integrated device is relatively complex, resulting in high construction costs; second, in the above-mentioned industrial silicon smelting flue gas treatment system, the shell of the flue constituting the first waste heat recovery unit and the shell of the flue constituting the second waste heat recovery unit are connected as a whole so that the first waste heat recovery unit and the second waste heat recovery unit constitute an integrated heat exchange device. Because the exhaust direction of the dust removal and denitrification integrated device is far away from the integrated heat exchange device, the subsequent exhaust pipe of the dust removal and denitrification integrated device needs to be bent by 180° (see Figure 11 in CN114887409A), which not only increases the construction cost of the exhaust pipe, but also increases the airflow pressure loss.

[0005] In short, the composition of the existing industrial silicon smelting flue gas treatment system and the structural design of the first waste heat boiler unit, integrated dust removal and denitrification equipment and other equipment still need to be improved and perfected. Utility Model Content

[0006] The objectives of the present disclosure include: 1) providing an industrial silicon smelting flue gas treatment system to solve the technical problem of heavy workload of the flue gas filtration and dust collector unit when the flue gas desulfurization unit is adjusted and deployed between the first waste heat boiler unit and the flue gas filtration and dust collector unit; 2) providing an industrial silicon smelting flue gas treatment system to solve the technical problem that the industrial silicon smelting furnace is also forced to shut down when the first waste heat boiler unit is shut down; 3) providing an integrated dust removal and denitrification equipment to solve the technical problem of complex structure of the existing integrated dust removal and denitrification equipment; 4) providing an industrial silicon smelting flue gas treatment system to solve the technical problem of high construction cost and large airflow pressure loss of the flue gas pipeline between the integrated dust removal and denitrification equipment and the integrated heat exchange equipment in the existing industrial silicon smelting flue gas treatment system.

[0007] In the first aspect, an industrial silicon smelting flue gas treatment system includes the following parts: a first waste heat recovery unit, which is used to receive the industrial silicon furnace smelting flue gas discharged from the industrial silicon smelting furnace and perform a first waste heat recovery to output a first cooled flue gas whose temperature drops to 180°C-450°C; a flue gas desulfurization unit, which is used to contact the first cooled flue gas with a desulfurizer to remove sulfur in the gas phase in the form of a solid phase or a carrier; a flue gas pre-dust collector unit, which is used to receive the first cooled flue gas and perform pre-dust removal on the first cooled flue gas by a mechanical dust removal method, and then output the pre-dusted flue gas and the first dust respectively; an air filter dust collector unit, for receiving the pre-dust-removed flue gas and filtering and dust-removing the pre-dust-removed flue gas through a filter element, and then outputting the dust-removed flue gas and a second dust respectively; an SCR denitration reactor unit, for receiving the dust-removed flue gas added with an SCR denitration reductant, and then outputting the denitration flue gas after passing through an SCR denitration catalyst; and a dust conveying unit, for conveying the first dust and the second dust to a dust densification device, or for returning a portion of the first dust to the flue gas desulfurization unit and conveying a portion of the first dust and the second dust to a dust densification device.

[0008] The industrial silicon smelting flue gas treatment system of the first aspect mentioned above not only adds a flue gas pre-dust collector unit between the flue gas desulfurization unit and the flue gas filtering dust collector unit, but also transports at least a portion of the first dust recovered by the flue gas pre-dust collector unit to the dust densification device through the dust conveying unit instead of returning it to the flue gas desulfurization unit. In this way, the continuous enrichment of dust in the flue gas desulfurization unit resulting in excessively high dust content in the pre-dust-removed flue gas at the inlet of the flue gas filtering dust collector unit is avoided, thereby reducing the workload of the flue gas filtering dust collector unit and avoiding a too rapid reduction in the filtration flux of the flue gas filtering dust collector unit.

[0009] In the second aspect, an industrial silicon smelting flue gas treatment system includes the following parts: a first waste heat recovery unit, which is used to receive the industrial silicon furnace smelting flue gas discharged from the industrial silicon smelting furnace and perform the first waste heat recovery to output the first cooled flue gas with the temperature dropped to 180℃-450℃; a flue gas filtering and dust collecting unit, which is used to receive the first cooled flue gas and filter and remove the dust in the first cooled flue gas through a filter element to output the dust-removed flue gas; an SCR denitrification reactor unit, which is used to receive the dust-removed flue gas added with an SCR denitrification reductant and output the denitrified flue gas after passing through an SCR denitrification catalyst; wherein a first pipeline connected in parallel with the first waste heat recovery unit is arranged on the side of the first waste heat recovery unit, a second pipeline is connected to the first pipeline, and valves are arranged at the inlet of the first pipeline, the inlet of the first waste heat recovery unit and the inlet of the second pipeline, and a cooling air intake device is connected to the inlet of the second pipeline.

[0010] When the industrial silicon smelting flue gas treatment system of the first aspect is working, when the valve at the inlet of the first pipeline is closed and the valve at the inlet of the first waste heat recovery unit is opened, the industrial silicon furnace smelting flue gas discharged from the industrial silicon smelting furnace passes through the first waste heat recovery unit. At this time, the industrial silicon furnace smelting flue gas becomes the first cooled flue gas after being recycled by the first waste heat; when the first waste heat recovery unit fails or needs maintenance, the valve at the inlet of the first pipeline is opened and the valve at the inlet of the first waste heat recovery unit is closed. At the same time, the inlet valve of the second pipeline is opened, and the cooling gas (such as air) is input into the first pipeline through the second pipeline through the cooling gas intake device to mix with the industrial silicon furnace smelting flue gas to reduce the temperature of the industrial silicon furnace smelting flue gas. At this time, the industrial silicon furnace smelting flue gas becomes the first cooled flue gas after being mixed with the cooling gas. In this way, even if the first waste heat boiler unit is shut down, the industrial silicon smelting flue gas treatment system can continue to work, thereby avoiding the shutdown of the industrial silicon smelting furnace.

[0011] In the third aspect, an integrated dust removal and denitrification device comprises: A) a first box body, wherein the interior of the first box body has the following compartments separated by a partition system in the first box body: A1) a left dust collector main cabin body, wherein the left dust collector main cabin body has one or more left dust collector compartments arranged in sequence along the front-to-back direction, each left dust collector compartment has a left dust collector lower original air cabin and a left dust collector upper clean air cabin, a filter element mounting plate is provided between the left dust collector lower original air cabin and the left dust collector upper clean air cabin, and a filter element is mounted on the filter element mounting plate and extends downward into the left dust collector lower original air cabin; A2) a right dust collector main cabin body, wherein the right The dust collector main cabin body has more than one right dust collector compartment arranged in sequence along the front-to-back direction, each right dust collector compartment has a lower raw air compartment of the right dust collector and an upper clean air compartment of the right dust collector, a filter element mounting plate is provided between the lower raw air compartment of the right dust collector and the upper clean air compartment of the right dust collector, a filter element extending downward into the lower raw air compartment of the left dust collector is mounted on the filter element mounting plate; A3) an intermediate flue main cabin body, the intermediate flue main cabin body is located between the left dust collector main cabin body and the right dust collector main cabin body and has a lower air intake flue cabin and an upper exhaust flue cabin, the lower air intake flue cabin extends along the front-to-back direction and is respectively connected to the lower air intake flue cabin of each left dust collector The original air chamber is connected to the original air chamber at the bottom of each right dust collector, and the upper air inlet flue chamber extends in the front-to-back direction; B) a second box body, the second box body is arranged on the top of the first box body and a channel is reserved on the top surface of the first box body and located around the second box body, and the second box body has the following compartments separated by the partition system in the second box body: B1) a left air collecting chamber, the lower part of the left air collecting chamber is arranged above the main chamber body of the left dust collector and is connected to the upper clean air chamber of each left dust collector, and the upper exhaust port of the left air collecting chamber is provided on the upper right partition of the left air collecting chamber; B2) a right air collecting chamber, the lower part of the right air collecting chamber is arranged A right side air collecting chamber upper exhaust port is provided on the upper left partition plate of the right side air collecting chamber, which is above the right side dust collector main chamber body and connected with the upper clean air chamber of each right side dust collector; B3) An intermediate SCR denitration reaction chamber, wherein the intermediate SCR denitration reaction chamber is located between the left side air collecting chamber and the right side air collecting chamber, and the upper portion of the intermediate SCR denitration reaction chamber is respectively connected with the upper exhaust port of the left side air collecting chamber and the upper exhaust port of the right side air collecting chamber, and the lower portion of the intermediate SCR denitration reaction chamber is arranged above the intermediate flue main chamber body and connected with the upper exhaust flue chamber, and an SCR denitration catalyst bed is provided in the intermediate SCR denitration reaction chamber.

[0012] The integrated dust removal and denitrification equipment of the third aspect has the appearance characteristics of a combination of a large box (first box) and a small box (second box), and the small box is located on the top of the large box. Among them, the internal structure of the large box is relatively common, and the internal structure of the small box and the connection relationship between the small box and the large box are the key innovations of the integrated dust removal and denitrification equipment. The small box uses the left air collecting chamber and the right air collecting chamber to introduce the airflow in the upper clean air chamber of each left dust collector and the upper clean air chamber of each right dust collector from bottom to top into the small box, and then passes through the middle SCR denitrification reaction chamber from top to bottom. The airflow discharged from the middle SCR denitrification reaction chamber continues to enter the upper exhaust flue chamber downward, and then discharges the integrated dust removal and denitrification equipment through the upper exhaust flue chamber. The above-mentioned integrated dust removal and denitrification equipment directly uses the upper exhaust flue chamber in the large box to achieve exhaust, and a simple improvement is made on the basis of the existing dust collector structure to realize the integrated dust removal and denitrification solution. The advantages of the integrated dust removal and denitrification equipment in the third aspect mentioned above include simple structure and saving of construction cost, as well as convenient loading and unloading of SCR denitrification catalyst and saving of floor space.

[0013] In a fourth aspect, an industrial silicon smelting flue gas treatment system includes the following parts: a first waste heat recovery unit, which is used to receive the industrial silicon furnace smelting flue gas discharged from the industrial silicon smelting furnace and perform a first waste heat recovery to output a first cooled flue gas with a temperature dropped to 180°C-450°C; a flue gas filter dust collector unit, which is used to receive the first cooled flue gas and filter and dedust the dust in the first cooled flue gas through a filter element and then output the dust-removed flue gas; an SCR denitration reactor unit, which is used to receive the dust-removed flue gas to which an SCR denitration reducing agent is added and output the denitrated flue gas after passing through an SCR denitration catalyst; a second waste heat recovery unit, which is used to receive the denitrated flue gas and perform a second waste heat recovery to output a second cooled flue gas; a shell of the flue forming the first waste heat recovery unit The body is connected to the shell of the flue constituting the second waste heat recovery unit as a whole, so that the first waste heat recovery unit and the second waste heat recovery unit constitute an integrated heat exchange device, and the integrated heat exchange device has a first cooled flue gas exhaust port and a denitrified flue gas inlet located in a first direction; the SCR denitrification reactor unit is assembled on the flue gas filtration and dust collector unit to form an integrated dust removal and denitrification device, and the integrated dust removal and denitrification device has a first cooled flue gas inlet and a denitrified flue gas exhaust port located in a second direction; the first direction and the second direction are relative directions, the first cooled flue gas exhaust port and the first cooled flue gas inlet are connected to a flue gas supply channel, and the denitrified flue gas inlet and the denitrified flue gas exhaust port are connected to a flue gas reflux channel.

[0014] The industrial silicon smelting flue gas treatment system of the fourth aspect adopts an integrated dust removal and denitrification equipment and an integrated heat exchanger, and designs the first cooled flue gas exhaust port and the denitrified flue gas inlet of the integrated heat exchanger in the first direction, and designs the first cooled flue gas inlet and the denitrified flue gas exhaust port of the integrated dust removal and denitrification equipment in the second direction. The first direction and the second direction are relative directions. In this way, the flue gas recirculation channel connected between the denitrified flue gas inlet and the denitrified flue gas exhaust port does not need to make a 180° bend, which can reduce the construction cost and airflow pressure loss of the flue gas recirculation channel.

[0015] The present disclosure is further described below in conjunction with the accompanying drawings and specific embodiments. Additional aspects and advantages of the present disclosure will be partially given in the following description, partially become apparent from the following description, or be understood through practice. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The drawings constituting a part of this specification are used to assist in understanding the present disclosure. The contents provided in the drawings and their related descriptions in this specification may be used to explain the present disclosure, but shall not constitute an improper limitation on the present disclosure.

[0017] Figure 1 This is a structural principle diagram of an industrial silicon smelting flue gas treatment system according to an embodiment of the present disclosure.

[0018] Figure 2 for Figure 1 The actual three-dimensional design diagram of the industrial silicon smelting flue gas treatment system is shown.

[0019] Figure 3 for Figure 1 The actual three-dimensional design diagram of the industrial silicon smelting flue gas treatment system is shown.

[0020] Figure 4 for Figure 1 The actual three-dimensional design diagram of the industrial silicon smelting flue gas treatment system is shown.

[0021] Figure 5 It is a structural schematic diagram of an integrated dust removal and denitrification equipment according to an embodiment of the present disclosure. DETAILED DESCRIPTION

[0022] The present disclosure is described clearly and completely below in conjunction with the accompanying drawings. A person of ordinary skill in the art will be able to implement the present disclosure based on these descriptions. Before describing the present disclosure in conjunction with the accompanying drawings, it should be particularly noted that:

[0023] The technical solutions and technical features provided in each section, including the following description, can be combined with each other without conflict. In addition, where possible, these technical solutions, technical features and related combinations can be assigned specific technical themes and protected by relevant patents.

[0024] The embodiments of the present disclosure involved in the following description are generally only a part of the embodiments rather than all the embodiments. Based on these embodiments, all other embodiments obtained by ordinary technicians in this field without making creative work should fall within the scope of patent protection.

[0025] Regarding the terms and units in this specification: The terms "include", "comprises", "have" and any variations thereof in this specification, the corresponding claims and related parts are intended to cover non-exclusive inclusions. The terms "front", "rear", "left" and "right" in this specification, the corresponding claims and related parts represent relative positional relationships based on the drawings. In addition, other relevant terms and units can be reasonably interpreted based on the relevant content provided in this specification.

[0026] Figure 1 This is a structural principle diagram of an industrial silicon smelting flue gas treatment system according to an embodiment of the present disclosure. Figure 2 for Figure 1 The actual three-dimensional design diagram of the industrial silicon smelting flue gas treatment system is shown. Figure 3 for Figure 1 The actual three-dimensional design diagram of the industrial silicon smelting flue gas treatment system is shown. Figure 4 for Figure 1 The actual three-dimensional design diagram of the industrial silicon smelting flue gas treatment system is shown in Figure 1. Figure 1-Figure 4 As shown, the industrial silicon smelting flue gas treatment system includes a first waste heat recovery unit 11, a flue gas desulfurization unit 12, a flue gas pre-dust collector unit 13, a flue gas filtration dust collector unit 14, an SCR denitrification reactor unit 15, a second waste heat recovery unit 16, a dust conveying unit 17, a fan 3 and a chimney 4.

[0027] Among them, the first waste heat recovery unit 11 is used to receive the industrial silicon furnace smelting flue gas discharged from the industrial silicon smelting furnace 2 and perform the first waste heat recovery and utilization, and then output the first cooled flue gas with the temperature reduced to 180°C-450°C; the flue gas desulfurization unit 12 is used to contact the first cooled flue gas with a desulfurizer to remove the sulfur in the gas phase in the form of a solid phase or a carrier; the flue gas pre-dust collector unit 13 is used to receive the first cooled flue gas and perform pre-dust removal on the first cooled flue gas by mechanical dust removal, and then output the pre-dust-removed flue gas and the first dust respectively; the flue gas filtering dust collector unit 14 is used to receive the pre-dust-removed flue gas and filter and dedust the pre-dust-removed flue gas through a filter element The dust-removed flue gas and the second dust are output respectively; the SCR denitration reactor unit 15 is used for receiving the dust-removed flue gas to which the SCR denitration reducing agent is added and outputting the denitration flue gas after passing through the SCR denitration catalyst; the second waste heat recovery unit 16 is used for receiving the denitration flue gas and outputting the second cooled flue gas after performing the second waste heat recovery; the dust conveying unit 17 is used for conveying the first dust and the second dust to the dust densification device, or for returning a part of the first dust to the flue gas desulfurization unit and conveying a part of the first dust and the second dust to the dust densification device; the fan 3 is used for drawing the second cooled flue gas into the chimney 4 for discharge.

[0028] Generally speaking, the flue gas pre-dust collector unit 13 adopts a mechanical dust collector, which includes at least one of a gravity dust collector, an inertial dust collector, and a centrifugal dust collector. Optionally, the centrifugal dust collector is a cyclone dust collector.

[0029] In addition, the flue gas pre-dust collector unit 13 may include at least two mechanical dust collectors 131 arranged in series, thereby improving the dust removal efficiency of the flue gas pre-dust collector unit 13.

[0030] In an optional embodiment, the first dust output by the mechanical dust collector close to the flue gas desulfurization unit 12 among the at least two mechanical dust collectors 131 is returned to the flue gas desulfurization unit 12 through the dust conveying unit 17, and the first dust output by the mechanical dust collector close to the flue gas filtration dust collector unit 14 among the at least two mechanical dust collectors 131 is conveyed to the dust encryption device 18 through the dust conveying unit 17.

[0031] In an optional embodiment, the first dust output by the mechanical dust collector close to the flue gas desulfurization unit 12 among the at least two mechanical dust collectors 131 is transported to the dust encryption device 18 through the dust conveying unit 17, and the first dust output by the mechanical dust collector close to the flue gas filtration dust collector unit 14 among the at least two mechanical dust collectors 131 is transported to the dust encryption device 18 through the dust conveying unit 17.

[0032] The dust encryption device 18 is already available and can directly adopt the micro-silicon powder encryption device widely used in the current industrial silicon smelting flue gas treatment system.

[0033] The dust conveying unit 17 may adopt a conventional dust conveying mechanism, such as a pneumatic dust conveying system or a mechanical dust conveying system.

[0034] A flue gas pre-dust collector unit 13 is added between the flue gas desulfurization unit 12 and the flue gas filtering dust collector unit 14, and at the same time, at least a portion of the first dust recovered by the flue gas pre-dust collector unit 13 is conveyed to the dust densification device 18 through the dust conveying unit 17 instead of returning to the flue gas desulfurization unit 12 (according to convention, the dust recovered by the mechanical dust collector 131 is usually returned to the flue gas desulfurization unit 12 to achieve the recycling of the desulfurizer). In this way, the continuous enrichment of dust in the flue gas desulfurization unit 12 resulting in an excessively high dust content in the pre-dust-removed flue gas at the inlet of the flue gas filtering dust collector unit 14 is avoided, thereby reducing the workload of the flue gas filtering dust collector unit 14 and avoiding a too rapid reduction in the filtration flux of the flue gas filtering dust collector unit 14. Since the dust collected in the dust encryption device 18 originally contains unreacted desulfurizer, it needs to be separated from the microsilica powder and then recovered. Therefore, conveying the first dust recovered by the flue gas pre-dust collector unit 13 to the dust encryption device 18 will not cause difficulties and increase consumption in the subsequent separation of the dust collected in the dust encryption device 18.

[0035] Furthermore, since the dust content of the pre-dusted flue gas at the inlet of the flue gas filter dust collector unit 14 is controlled, the flue gas filter dust collector unit 14 can use a flue gas filter dust collector with a filtration wind speed set to 0.8m / min-1.2m / min. The filtration wind speed V is the air volume Q (in m2) passing through the flue gas filter dust collector unit 14. 3 ) and the filtration area S (unit: m 2 ) and time T (unit min), which is expressed as V=Q / (S*T). Among them, the filtration area refers to the sum of the filtration areas of the filter elements in the flue gas filtration dust collector unit 14. In the past, due to the high dust content of the pre-dust-removed flue gas at the inlet of the flue gas filtration dust collector unit 14, the filtration wind speed needs to be set at less than 0.7m / min (for example, 0.5m / min), which results in the need to design a larger filtration area for the flue gas filtration dust collector unit 14, thereby significantly increasing the cost of the flue gas filtration dust collector unit 14. Since the dust content of the pre-dust-removed flue gas at the inlet of the flue gas filtration dust collector unit 14 is controlled, the flue gas filtration dust collector unit 14 adopts a flue gas filtration dust collector with a filtration wind speed set at 0.8m / min-1.2m / min, which reduces the cost of the flue gas filtration dust collector unit 14.

[0036] The desulfurizing agent may be at least one of calcium carbonate powder, calcium hydroxide powder, sodium carbonate powder, and sodium hydroxide powder.

[0037] The flue gas desulfurization unit 12 may be a desulfurization tower. The flue gas desulfurization unit 12 may also be any structure other than a desulfurization tower that can mix the desulfurizer with the first cooled flue gas, including a conveying pipeline for the first cooled flue gas.

[0038] The first waste heat recovery unit 11 can usually use a waste heat boiler. Specifically, the first waste heat recovery unit uses a waste heat boiler that reduces the temperature of the industrial silicon furnace smelting flue gas to 300℃-450℃ or ≥180℃ and <300℃. If the temperature of the first cooled flue gas output by the first waste heat recovery unit is 300℃-450℃, the SCR denitration catalyst in the SCR denitration reactor unit 15 uses a medium-high temperature SCR denitration catalyst; if the temperature of the first cooled flue gas output by the first waste heat recovery unit is ≥180℃ and <300℃, the SCR denitration catalyst in the SCR denitration reactor unit 15 uses a low-temperature SCR denitration catalyst. The second waste heat recovery unit 16 can use a waste heat boiler or an economizer.

[0039] The shell of the flue constituting the first waste heat recovery unit 11 and the shell of the flue constituting the second waste heat recovery unit 16 can also be connected as one so that the first waste heat recovery unit 11 and the second waste heat recovery unit 16 constitute an integrated heat exchange device.

[0040] The SCR denitration reactor unit 15 can be assembled on the flue gas filtration dust collector unit 14 to form an integrated dust removal and denitration device.

[0041] like Figure 1-Figure 4 As shown, in a specific embodiment, the integrated heat exchanger has a first cooled flue gas exhaust port and a denitrified flue gas inlet located in a first direction, and at the same time, the integrated dust removal and denitrification equipment has a pre-dust-removed flue gas inlet and a denitrified flue gas exhaust port located in a second direction, the first direction and the second direction are relative directions, the flue gas desulfurization unit 12 and the flue gas pre-dust collector unit 13 are connected in series on the flue gas air supply channel between the first cooled flue gas exhaust port and the pre-dust-removed flue gas inlet, and the denitrified flue gas inlet and the denitrified flue gas exhaust port are connected to a flue gas reflux channel.

[0042] Since the first cooled flue gas exhaust port and the denitrified flue gas inlet of the integrated heat exchanger equipment are designed in the first direction on the basis of adopting the integrated dust removal and denitrification equipment and the integrated heat exchanger equipment, and the first cooled flue gas inlet (specifically the pre-dust-removed flue gas inlet here) and the denitrified flue gas exhaust port of the integrated dust removal and denitrification equipment are designed in the second direction, the first direction and the second direction are relative directions. In this way, the flue gas recirculation channel connected between the denitrified flue gas inlet and the denitrified flue gas exhaust port does not need to make a 180° bend, which can reduce the construction cost and airflow pressure loss of the flue gas recirculation channel.

[0043] In an improved implementation, a first pipeline 111 connected in parallel with the first waste heat recovery unit 11 is also provided next to the first waste heat recovery unit 11, and a second pipeline 112 is connected to the first pipeline 111. The inlet of the first pipeline, the inlet of the first waste heat recovery unit and the inlet of the second pipeline are all provided with valves 113, 114, 115, and the inlet of the second pipeline 112 is connected to a cooling air intake device 116.

[0044] In this way, when the valve 114 at the inlet of the first pipeline 111 is closed and the valve 113 at the inlet of the first waste heat recovery unit 11 is opened, the industrial silicon furnace smelting flue gas discharged from the industrial silicon smelting furnace 2 passes through the first waste heat recovery unit 11. At this time, the industrial silicon furnace smelting flue gas becomes the first cooled flue gas after being recycled by the first waste heat; when the first waste heat recovery unit 11 fails or needs maintenance, the valve 114 at the inlet of the first pipeline 111 is opened and the valve 113 at the inlet of the first waste heat recovery unit 11 is closed. At the same time, the inlet valve 115 of the second pipeline 112 is opened, and the cooling gas (such as air) is input into the first pipeline 111 through the second pipeline 112 through the cooling gas intake device 116 to mix with the industrial silicon furnace smelting flue gas to reduce the temperature of the industrial silicon furnace smelting flue gas. At this time, the industrial silicon furnace smelting flue gas becomes the first cooled flue gas after being mixed with the cooling gas. Therefore, even if the first waste heat boiler unit 11 is shut down, the industrial silicon smelting flue gas treatment system can continue to work, thereby avoiding the shutdown of the industrial silicon smelting furnace.

[0045] The cooling air intake device 116 may be a fan, which is used to draw outside air into the second pipeline 112 so as to mix with the industrial silicon furnace smelting flue gas.

[0046] Figure 5 It is a structural schematic diagram of an integrated dust removal and denitrification equipment according to an embodiment of the present disclosure. Figure 1-Figure 4 The industrial silicon smelting flue gas treatment system shown in the figure specifically adopts the integrated dust removal and denitrification equipment. Figure 5As shown, an integrated dust removal and denitrification equipment comprises: A) a first box body 51, wherein the first box body has the following compartments separated by a partition system in the first box body: A1) a left dust collector main cabin body, wherein the left dust collector main cabin body has more than one left dust collector compartments arranged in sequence along the front-to-back direction, wherein each left dust collector compartment has a left dust collector lower original air cabin and a left dust collector upper clean air cabin, and a filter element mounting plate is provided between the left dust collector lower original air cabin and the left dust collector upper clean air cabin, and a filter element extending downward into the left dust collector lower original air cabin is mounted on the filter element mounting plate; A2) a right dust collector main cabin body, wherein the right dust collector A3) The main cabin body of the left dust collector has more than one right dust collector compartment arranged in sequence along the front-to-back direction, each right dust collector compartment has a lower raw air compartment of the right dust collector and an upper clean air compartment of the right dust collector, a filter element mounting plate is provided between the lower raw air compartment of the right dust collector and the upper clean air compartment of the right dust collector, a filter element extending downward into the lower raw air compartment of the left dust collector is mounted on the filter element mounting plate; A3) The main cabin body of the middle flue, the main cabin body of the middle flue is located between the main cabin body of the left dust collector and the main cabin body of the right dust collector and has a lower air intake flue compartment 53 and an upper exhaust flue compartment 54, the lower air intake flue compartment extends along the front-to-back direction and is respectively connected to the lower air intake flue compartments of each left dust collector The upper original air chamber is connected with the lower original air chamber of each right dust collector, and the upper air inlet flue chamber extends in the front-to-back direction; B) a second box body 52, the second box body is arranged on the top of the first box body and a channel is reserved on the top surface of the first box body around the second box body, and the second box body has the following compartments separated by the partition system in the second box body: B1) a left air collecting chamber, the lower part of the left air collecting chamber is arranged above the main chamber body of the left dust collector and is connected with the upper clean air chamber of each left dust collector, and the upper right partition of the left air collecting chamber is provided with an upper exhaust port of the left air collecting chamber; B2) a right air collecting chamber, the lower part of the right air collecting chamber is provided It is arranged above the main cabin body of the right dust collector and is communicated with the upper clean air cabin of each right dust collector, and an upper exhaust port of the right air collecting cabin is provided on the upper left partition plate of the right air collecting cabin; B3) An intermediate SCR denitration reaction cabin, wherein the intermediate SCR denitration reaction cabin is located between the left air collecting cabin and the right air collecting cabin, and the upper part of the intermediate SCR denitration reaction cabin is respectively communicated with the upper exhaust port of the left air collecting cabin and the upper exhaust port of the right air collecting cabin, and the lower part of the intermediate SCR denitration reaction cabin is arranged above the main cabin body of the intermediate flue and is communicated with the upper exhaust flue cabin, and an SCR denitration catalyst bed is arranged in the intermediate SCR denitration reaction cabin.

[0047] Wherein, the total air inlet of the lower air inlet flue compartment and the total exhaust outlet of the upper exhaust flue compartment are arranged on the same side in the front-to-back direction of the second box body (see Figure 3 ) or the opposite side.

[0048] The SCR denitration catalyst used in the SCR denitration catalyst bed may be a medium-high temperature SCR denitration catalyst or a low-temperature SCR denitration catalyst.

[0049] Wherein, the filter element can be a metal filter bag, a ceramic tubular filter element or a metal tubular filter element. When the temperature of the flue gas entering the integrated dust removal and denitration equipment is low, the filter element can also be a cloth bag.

[0050] The integrated dust removal and denitrification equipment of the third aspect has the appearance characteristics of a combination of a large box (first box 51) and a small box (second box 52), and the small box is located on the top of the large box. Among them, the internal structure of the large box is relatively common, and the internal structure of the small box and the connection relationship between the small box and the large box are the key innovations of the integrated dust removal and denitrification equipment. The small box uses the left air collecting chamber and the right air collecting chamber to introduce the airflow in the upper clean air chamber of each left dust collector and the upper clean air chamber of each right dust collector from bottom to top into the small box, and then passes through the middle SCR denitrification reaction chamber from top to bottom. The airflow discharged from the middle SCR denitrification reaction chamber continues to enter the upper exhaust flue chamber downward, and then the integrated dust removal and denitrification equipment is discharged through the upper exhaust flue chamber. The above-mentioned integrated dust removal and denitrification equipment directly uses the upper exhaust flue chamber 54 in the large box to achieve exhaust, and a simple improvement is made on the basis of the existing dust collector structure to realize the integrated dust removal and denitrification solution. The advantages of the integrated dust removal and denitrification equipment in the third aspect mentioned above include simple structure and saving of construction cost, as well as convenient loading and unloading of SCR denitrification catalyst and saving of floor space.

[0051] In a preferred embodiment, the second box is located at the center of the top of the first box, and a channel is reserved on the top surface of the first box around the second box. In a common embodiment, both the first box and the second box are rectangular boxes.

[0052] In a preferred embodiment, when the total air inlet of the lower air intake flue compartment and the total exhaust port of the upper exhaust flue compartment are arranged on the same side in the front-to-back direction of the second box body, the top plate of the lower air intake flue compartment and the bottom plate of the upper exhaust flue compartment form a conical structure, so that the cross-sectional area of ​​the lower air intake flue compartment in the front-to-back direction gradually decreases along the air intake direction and the cross-sectional area of ​​the upper exhaust flue compartment in the front-to-back direction gradually increases along the exhaust direction.

[0053] In a common implementation, an ash hopper 55 is provided at the bottom of the raw air chamber at the bottom of each left dust collector and at the bottom of the raw air chamber at the bottom of each right dust collector, and an ash unloading device is provided at the bottom of each ash hopper.

[0054] In an optional implementation, the lower air intake flue chamber 53 is connected to the side of each ash hopper through an independent air intake manifold, and an air intake valve is installed on each air intake manifold.

[0055] In a preferred embodiment, at least two layers of SCR denitration catalyst beds arranged vertically are provided in the intermediate SCR denitration reaction chamber.

[0056] An industrial silicon smelting flue gas treatment system according to another embodiment of the present disclosure includes a first waste heat recovery unit 11, a flue gas desulfurization unit, a second flue gas filter dust collector unit, a flue gas filter dust collector unit 14, an SCR denitrification reactor unit 15, a second waste heat recovery unit 16, a fan 3 and a chimney 4.

[0057] Among them, the first waste heat recovery unit 11 is used to receive the industrial silicon furnace smelting flue gas discharged from the industrial silicon smelting furnace 2 and perform the first waste heat recovery and utilization to output the first cooled flue gas with the temperature reduced to 180°C-450°C; the flue gas filter dust collector unit 14 is used to receive the first cooled flue gas and filter and dedust the first cooled flue gas through a filter element and then output the dust-removed flue gas; the SCR denitration reactor unit 15 is used to receive the dust-removed flue gas added with the SCR denitration reducing agent and then output the denitration flue gas after passing through the SCR denitration catalyst; the second The waste heat recovery unit 16 is used to receive the denitrified flue gas and perform a second waste heat recovery and utilization before outputting a second cooled flue gas; the flue gas desulfurization unit is used to obtain the second cooled flue gas to which a desulfurizer is added and to remove the sulfur in the gas phase from the gas phase in the form of a solid phase or a carrier through the desulfurizer to obtain the desulfurized flue gas; the second flue gas filter and dust collector unit is used to obtain the desulfurized flue gas and filter and remove dust in the desulfurized flue gas through a filter element before outputting a second dust-removed flue gas; the fan 3 is used to draw the second dust-removed flue gas into the chimney 4 for discharge.

[0058] Among them, the shell of the flue constituting the first waste heat recovery unit is connected as a whole with the shell of the flue constituting the second waste heat recovery unit so that the first waste heat recovery unit and the second waste heat recovery unit constitute an integrated heat exchange device, and the integrated heat exchange device has a first cooled flue gas exhaust port and a denitrified flue gas inlet located in a first direction; the SCR denitrification reactor unit is assembled on the flue gas filter and dust collector unit to form an integrated dust removal and denitrification device, and the integrated dust removal and denitrification device has a first cooled flue gas inlet and a denitrified flue gas exhaust port located in a second direction; the first direction and the second direction are relative directions, the first cooled flue gas exhaust port and the first cooled flue gas inlet are connected to a flue gas supply channel, and the denitrified flue gas inlet and the denitrified flue gas exhaust port are connected to a flue gas reflux channel.

[0059] Wherein, the integrated dust removal and denitrification equipment comprises: A) a first box body, the interior of which has the following compartments separated by a partition system in the first box body: A1) a left dust collector main cabin body, the left dust collector main cabin body has more than one left dust collector compartments arranged in sequence along the front-to-back direction, each left dust collector compartment has a left dust collector lower original air cabin and a left dust collector upper clean air cabin, a filter element mounting plate is provided between the left dust collector lower original air cabin and the left dust collector upper clean air cabin, a filter element mounting plate is provided with a filter element extending downward into the left dust collector lower original air cabin; A2) a right dust collector main cabin body, the right dust collector main cabin body has more than one left dust collector compartments arranged in sequence along the front-to-back direction A3) right dust collector compartments arranged in order, each right dust collector compartment has a lower raw air compartment of the right dust collector and an upper clean air compartment of the right dust collector, a filter element mounting plate is provided between the lower raw air compartment of the right dust collector and the upper clean air compartment of the right dust collector, a filter element mounting plate is installed with a filter element extending downward into the lower raw air compartment of the left dust collector; A3) intermediate flue main cabin body, the intermediate flue main cabin body is located between the left dust collector main cabin body and the right dust collector main cabin body and has a lower air intake flue cabin and an upper exhaust flue cabin, the lower air intake flue cabin extends along the front-to-back direction and is respectively communicated with the lower raw air compartments of each left dust collector and the lower raw air compartments of each right dust collector, the upper air intake flue cabin extends along the front-to-back direction Extending toward the top; B) a second box body, which is arranged on the top of the first box body and has a reserved channel on the top surface of the first box body and located around the second box body, and the interior of the second box body has the following compartments separated by the partition system in the second box body: B1) a left-side air collecting cabin, the lower portion of which is arranged above the left-side dust collector main cabin body and is communicated with the upper clean air cabins of each left-side dust collector, and an upper exhaust port of the left-side air collecting cabin is provided on the upper right partition of the left-side air collecting cabin; B2) a right-side air collecting cabin, the lower portion of which is arranged above the right-side dust collector main cabin body and is communicated with the upper clean air cabins of each right-side dust collector, and the upper left partition of the right-side air collecting cabin A right-side gas collecting chamber upper exhaust port is provided; B3) an intermediate SCR denitration reaction chamber, the intermediate SCR denitration reaction chamber is located between the left-side gas collecting chamber and the right-side gas collecting chamber, the upper portion of the intermediate SCR denitration reaction chamber is respectively communicated with the left-side gas collecting chamber upper exhaust port and the right-side gas collecting chamber upper exhaust port, the lower portion of the intermediate SCR denitration reaction chamber is arranged above the intermediate flue main chamber body and is communicated with the upper exhaust flue chamber, and an SCR denitration catalyst bed is provided in the intermediate SCR denitration reaction chamber; wherein the total air inlet of the lower air inlet flue chamber and the total exhaust port of the upper exhaust flue chamber are arranged on the same side of the second box body in the front-to-back direction and face the second direction.

[0060] The above is a description of the relevant contents of the present disclosure. A person skilled in the art will be able to implement the present disclosure based on these descriptions. Based on the above contents of this specification, all other embodiments obtained by a person skilled in the art without making any creative work shall fall within the scope of patent protection.

Claims

1. An industrial silicon smelting flue gas treatment system, characterized by: Includes the following parts: The first waste heat recovery unit is used to receive the industrial silicon furnace smelting flue gas discharged from the industrial silicon smelting furnace and perform first waste heat recovery to output the first cooled flue gas with the temperature reduced to 180°C-450°C; A flue gas filtering and dust removal unit, configured to receive the first cooled flue gas and filter and remove dust in the first cooled flue gas through a filter element and then output dust-removed flue gas; An SCR denitration reactor unit is used to receive the dust-removed flue gas to which an SCR denitration reducing agent is added and output the denitration flue gas after passing through an SCR denitration catalyst; Among them, a first pipeline connected in parallel with the first waste heat recovery unit is arranged beside the first waste heat recovery unit, a second pipeline is connected to the first pipeline, the inlet of the first pipeline, the inlet of the first waste heat recovery unit and the inlet of the second pipeline are all provided with valves, and the inlet of the second pipeline is connected to a cooling air intake device.

2. An industrial silicon smelting flue gas treatment system according to claim 1, characterized in that: It also includes a flue gas desulfurization unit and a flue gas pre-dust collector unit located between the first waste heat recovery unit and the flue gas filter dust collector unit; The flue gas desulfurization unit is used to contact the first cooled flue gas with a desulfurizer to remove sulfur in the gas phase in the form of a solid phase or a carrier; The flue gas pre-dust collector unit is used to receive the first cooled flue gas and perform pre-dust removal on the first cooled flue gas by mechanical dust removal, and then output the pre-dust-removed flue gas and the first dust respectively; The flue gas filtering and dust removal unit is used to receive the pre-dust-removed flue gas and filter and dedust the first cooled flue gas through a filter element, and then output the dust-removed flue gas and the second dust respectively.

3. An industrial silicon smelting flue gas treatment system as claimed in claim 2, characterized in that: It also includes a dust conveying unit for conveying the first dust and the second dust to a dust encryption device, or for returning a portion of the first dust to the flue gas desulfurization unit and conveying a portion of the first dust and the second dust to a dust encryption device.

4. An industrial silicon smelting flue gas treatment system as claimed in claim 3, characterized in that: The flue gas pre-dust collector unit adopts a mechanical dust collector, and the mechanical dust collector includes at least one of a gravity dust collector, an inertial dust collector, and a centrifugal dust collector.

5. An industrial silicon smelting flue gas treatment system as claimed in claim 4, characterized in that: The centrifugal dust collector is a cyclone dust collector.

6. An industrial silicon smelting flue gas treatment system as claimed in claim 4, characterized in that: The flue gas pre-dust collector unit comprises at least two mechanical dust collectors arranged in series.

7. An industrial silicon smelting flue gas treatment system as claimed in claim 6, characterized in that: The first dust output by the mechanical dust collector close to the flue gas desulfurization unit among the at least two mechanical dust collectors is returned to the flue gas desulfurization unit and / or is transported to the dust encryption device through the dust conveying unit, and the first dust output by the mechanical dust collector close to the flue gas filtration dust collector unit among the at least two mechanical dust collectors is transported to the dust encryption device through the dust conveying unit.

8. An industrial silicon smelting flue gas treatment system as claimed in claim 3, characterized in that: The flue gas filter dust collector unit adopts a flue gas filter dust collector with a filtering wind speed set to 0.8m / min-1.2m / min.

9. The industrial silicon smelting flue gas treatment system according to claim 1, characterized in that: include: The second waste heat recovery unit is used to receive the denitrified flue gas and perform a second waste heat recovery and utilization to output a second cooled flue gas.

10. An industrial silicon smelting flue gas treatment system according to claim 9, characterized in that: The shell of the flue constituting the first waste heat recovery unit is connected to the shell of the flue constituting the second waste heat recovery unit as a whole so that the first waste heat recovery unit and the second waste heat recovery unit constitute an integrated heat exchange device, and the integrated heat exchange device has a first cooled flue gas exhaust port and a denitrified flue gas inlet located in a first direction; The SCR denitration reactor unit is assembled on the flue gas filter dust collector unit to form a dust removal and denitration integrated device, and the dust removal and denitration integrated device has a pre-dust-removed flue gas inlet and a denitration flue gas exhaust port located in the second direction; The first direction and the second direction are relative directions, a flue gas supply channel is connected between the first cooled flue gas exhaust port and the pre-dust-removed flue gas inlet, and a flue gas reflux channel is connected between the denitrified flue gas inlet and the denitrified flue gas exhaust port.

Images