Process method for extracting sodium sulfite product through sodium desulfurization post-treatment and dust removal device

Abstract

The invention belongs to the technical field of desulfurization environmental protection, and particularly relates to a process method for extracting a sodium sulfite product through sodium desulfurization post-treatment and a dust removal device. Comprising the following steps: absorbing saturated desulfurization mother liquor in a desulfurization device, conveying the saturated desulfurization mother liquor into a desulfurization mother liquor tank by a slurry discharge pump, adding a sodium hydroxide solution with a certain concentration into the desulfurization mother liquor tank, and reacting and crystallizing to separate out a certain amount of sodium sulfite crystals; conveying the slurry in which a certain amount of crystals are separated out into a cyclone separator through a desulfurization mother liquor pump, and carrying out solid-liquid pre-separation in the cyclone separator; according to the invention, industrial waste gas generated after extraction of sodium sulfite can be reused, and pollution is reduced; the filtering membrane adsorbing sodium sulfite can be thoroughly cleaned; the unextracted sodium sulfite mixed in the dried and separated waste gas can be fully extracted and recovered, so that the extraction rate is increased; and stacking and packaging are carried out while the sodium sulfite is recycled, so that the collecting and packaging efficiency is improved.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of desulfurization and environmental protection technology, and particularly relates to a process method for extracting sodium sulfite product after sodium desulfurization post-treatment and a dust removal device. BACKGROUND

[0002] As the most widely used desulfurization process, wet desulfurization process accounts for about 85% of the total desulfurization installed capacity in the world. Due to the adaptability of the petrochemical industry to sodium hydroxide, sodium desulfurization, as a member of wet desulfurization, is widely used in the petrochemical industry. Anhydrous sodium sulfite, as a kind of sodium sulfite, is widely used in artificial fiber stabilizer, paper industry lignin remover, dyeing and bleaching industry reducing agent, leather industry oxygen inhibitor, photographic developer and food additive. It is widely used and has good economic benefits, and is a good by-product of sodium desulfurization.

[0003] Currently, anhydrous sodium sulfite is mainly produced by evaporation crystallization in industry. By using the principles of salting-out crystallization, common ion effect and solubility difference, evaporation concentration, crystallization growth, solid-liquid separation, drying and packaging are carried out in turn, and finally industrial anhydrous sodium sulfite is obtained. However, the existing process device is complex, has many fault points, consumes a lot of energy, and has high operation cost. At the same time, due to the gradual improvement of environmental protection requirements in recent years, the traditional sodium desulfurization process which produces high-salinity wastewater directly discharges the industrial waste gas generated after extracting sodium sulfite, which cannot meet the latest zero-emission requirements. Moreover, the waste gas after drying and separation still contains part of the unextracted sodium sulfite, which is not fully extracted, and the resource utilization rate is low. The filter membrane after dust removal and extraction of sodium sulfite is difficult to clean, and the high frequency of replacing the filter membrane will cause the equipment to frequently stop production, resulting in economic losses. Moreover, the extracted sodium sulfite needs to be dried, stacked and packaged separately, which consumes a lot of energy. SUMMARY

[0004] In order to solve the problems in the prior art, the present application provides a process method for extracting sodium sulfite product after sodium desulfurization post-treatment, which can utilize the industrial waste gas generated after extracting sodium sulfite again, reduce pollution emissions, has the advantages of simple process device, can reduce fault points and energy consumption, and reduce operation cost. The present application also provides a dust removal device for extracting sodium sulfite product after sodium desulfurization post-treatment, which fully extracts and recovers the unextracted sodium sulfite still contained in the waste gas after drying and separation by the cooperation of the container assembly, the filter assembly and the stacking assembly, improves the resource utilization efficiency, completely cleans the filter membrane adsorbing sodium sulfite, reduces the replacement frequency of the filter membrane, and drives the stacking assembly to stack and package the sodium sulfite while driving the knocking assembly to knock the filter membrane to recover the sodium sulfite, which reduces the energy consumption of the equipment and improves the efficiency of collection and packaging.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: A process for extracting sodium sulfite from sodium desulfurization products includes the following steps: S101: The saturated desulfurization mother liquor absorbed in the desulfurization unit is transported to the desulfurization mother liquor tank by the slurry discharge pump. A certain concentration of sodium hydroxide solution is added to the desulfurization mother liquor tank, and a certain amount of sodium sulfite crystals are precipitated by reaction and crystallization. S102: The slurry that has precipitated a certain amount of crystals is pumped to the hydrocyclone separator by the desulfurization mother liquor pump. Solid-liquid pre-separation is carried out in the hydrocyclone separator. The bottom slurry flows by gravity to the integrated centrifuge for concentration and filtration, and the supernatant flows by gravity to the filtrate tank. S103: Add a certain amount of antioxidant to the filtrate tank, mix it evenly with the clear liquid, and then pump it to the desulfurization tower slurry for recycling, while inhibiting the oxidation of sodium sulfite in the tower. S104: The concentrated phase flows to the integrated centrifuge for concentration and filtration, where it undergoes deep dehydration. After most of the water is removed, the product enters the fluidized bed dryer. After preheating, drying, and cooling in the fluidized bed dryer, anhydrous sodium sulfite is obtained. S105: The dried anhydrous sodium sulfite product is conveyed for stacking and packaging. The exhaust gas discharged from the fluidized bed dryer enters the dust removal device used for sodium desulfurization post-treatment to extract sodium sulfite product, and the sodium sulfite product entrained in the gas is separated and recovered. S106: The separated and recovered sodium sulfite product is transported to the stacking and packaging system, and the exhaust gas after dust removal is returned to the desulfurization tower for flue gas purification treatment, so as not to generate secondary pollution.

[0006] This invention also claims a dust removal device for extracting sodium sulfite products after sodium desulfurization, comprising a container assembly including a filter tank, a collection tank, a conveying tank, and a stacking tank, which are fixedly connected and communicate with each other from top to bottom. The filter tank has an inlet pipe and an outlet pipe connected to its inner cavity, and the inner cavity houses filter components arranged side-by-side. The inlet pipe communicates with the bottom of the filter tank's inner cavity, and the outlet pipe communicates with the bottom of the filter tank's inner cavity. A stacking assembly is fixedly connected to one end of the stacking tank, and the stacking assembly is configured to, when the motor is started, scrape and push particles falling into the inner cavity of the stacking tank toward the other end of the stacking tank, thus stacking them.

[0007] Furthermore, the filter assembly includes a support frame, which is fixedly connected to a corresponding fixing ring on the inner wall of the filter tank, and a filter membrane is placed at the bottom of the support frame. The stacking assembly includes a rotating rod, which passes through the center of the collection tank. The lower end of the rotating rod located outside the collection tank is connected to a motor drive, and the upper end of the rotating rod located inside the filter tank is fixedly connected to the center of multiple filter assemblies.

[0008] Furthermore, multiple pairs of ear plates are fixedly connected to the bracket, with mounting grooves provided between each pair of ear plates. Multiple first levers are fixedly connected to one end of the rotating rod located inside the filter tank. Each first lever is positioned above a corresponding filter assembly, and when the first lever rotates, it actuates the striking assembly to strike the filter membrane.

[0009] Furthermore, the striking assembly includes a mounting plate, with a striking shaft fixedly connected to the center of the mounting plate. Both ends of the striking shaft are rotatably connected to a pair of ear plates on either side of the mounting groove. A hammer rod and a push rod are fixedly connected to the arc surface of the mounting plate. A hammer head is fixedly connected to the end of the hammer rod furthest from the mounting plate, with the hammer head facing the filter membrane. When the first lever rotates, it contacts the push rod.

[0010] Furthermore, the filter assembly includes a mounting column, which is fixedly connected to the bottom center of the support. A membrane transfer assembly is rotatably connected to the outer wall of the mounting column. The membrane transfer assembly includes a fan-shaped body, on which a torsion spring rod is fixedly connected. The torsion spring rod extends in the direction away from the support. Multiple membrane fixing columns are circumferentially arranged on the side of the fan-shaped body facing the support. The filter membrane is fixedly connected to the membrane fixing columns. Multiple second levers are fixedly connected to the rotating rod. Each second lever is located under the corresponding membrane assembly. When the second lever rotates, it will collide with the torsion spring rod.

[0011] Furthermore, the stacking assembly includes a first gear located between the collection tank and the motor and fixedly connected to the rotating rod. A second gear meshes with the first gear and is fixedly connected to one end of the stacking rotating shaft. The other end of the stacking rotating shaft is rotatably connected to one end of a first connecting rod. The other end of the first connecting rod is rotatably connected to one end of a second connecting rod. The other end of the second connecting rod is hinged to one side of the stacking plate.

[0012] Furthermore, the stacking assembly includes a fixing plate, which is fixedly connected to the outer wall of the stacking tank, a motor is fixedly connected to the fixing plate, and the stacking shaft is rotatably fixed to the fixing plate.

[0013] Furthermore, the container assembly includes a housing that is detachably connected to the collection tank and the delivery tank. The cavity formed by the inner wall of the housing, the outer wall of the lower slope of the collection tank, and the side of the delivery tank near the stacking assembly houses the first gear, the second gear, and the motor.

[0014] Furthermore, the container assembly includes a base that is fixedly connected to and in communication with the stacked tank, and the first connecting rod is housed in the inner cavity of the base.

[0015] Compared with the prior art, the present invention has the following beneficial effects: (1) This invention provides a process for extracting sodium sulfite products after sodium desulfurization, which can reuse the industrial waste gas generated after sodium sulfite extraction and reduce pollution emissions; the raw material liquid is deeply dehydrated in a centrifuge with integrated concentration and filtration, and the product after removing most of the water enters a fluidized bed dryer. After drying and cooling in the fluidized bed dryer, anhydrous sodium sulfite is obtained. The anhydrous sodium sulfite product is output and stacked for packaging. The waste gas discharged from the fluidized bed dryer enters the dust removal device for extracting sodium sulfite products after sodium desulfurization, and the sodium sulfite product entrained in the gas is separated and recovered. The separated and recovered sodium sulfite product is transported to the stacking and packaging system. The waste gas after dust removal is returned to the desulfurization tower for flue gas purification treatment, so as not to generate secondary pollution.

[0016] (2) This invention also provides a dust removal device for extracting sodium sulfite products after sodium desulfurization, which can fully extract and recover unextracted sodium sulfite from the waste gas after drying and separation, thereby improving resource utilization efficiency; the waste gas after drying and extraction of sodium sulfite still contains some floating sodium sulfite particles, which will pass through the filter membrane on the filter assembly fixed in the inner cavity of the filter tank in sequence. Under the filtration and adsorption effect of the filter membrane, the sodium sulfite particles entrained in the waste gas will be adsorbed on the filter membrane. A lever rotation triggers a push rod on the striking assembly. The push rod, under pressure, rotates the mounting plate along the striking shaft, causing the hammer rod and hammerhead fixed on the mounting plate to lift up. Once the first lever is disengaged and no longer in contact with the push rod, the hammerhead falls under its own weight and strikes the filter membrane, causing the sodium sulfite particles attached to the filter membrane to be shaken off. The fallen sodium sulfite particles fall into the inner cavity of the stacking tank. Finally, the stacking assembly completes the stacking and packaging process, realizing the recovery and extraction of sodium sulfite entrained in the exhaust gas and improving resource utilization efficiency.

[0017] (3) This invention can also thoroughly clean the filter membrane that adsorbs sodium sulfite, reducing the frequency of filter membrane replacement. The fan-shaped body is located between the bottom ring of the mounting column and the bottom surface of the bracket, and there is a gap between the fan-shaped body and the bottom surface of the bracket for placing the filter membrane. The filter membrane will rotate with the fan-shaped body. At this time, the bracket is fixedly connected to the corresponding fixed ring and the bracket will not rotate. Also, because the second lever fixedly connected to the rotating rod will collide with the torsion spring rod fixedly connected to the side of the fan-shaped body when it rotates with the rotating rod, the torsion spring rod will be forced to drive the fan-shaped body and the filter membrane to rotate until it separates from the second lever and no longer touches it. Then, the torsion spring rod will reset under the action of the torsion spring, and the rotation of the fan-shaped body and the filter membrane will slow down. This makes the rotation speed of the first lever on the rotating rod and the filter membrane inconsistent. The first lever will push the striking component to strike the filter membrane, and the striking point will change constantly, covering every circumferential angle on the filter membrane. Therefore, the filter membrane can be thoroughly and fully cleaned, reducing the frequency of filter membrane replacement and maintenance, and avoiding the economic loss caused by frequent equipment downtime due to excessive filter membrane replacement frequency.

[0018] (4) When the present invention drives the striking component to separate and recover sodium sulfite, it also drives the stacking component to stack and package the sodium sulfite, which reduces equipment energy consumption and improves the efficiency of collection and packaging operations. When the driving rod rotates and drives the striking component to strike the filter membrane to separate sodium sulfite, the first gear fixedly connected to the rotating rod also rotates, and the second gear rotates at the same time. The first connecting rod connected to the stacking shaft rotates. Since one end of the second connecting rod is rotatably connected to the end of the first connecting rod away from the stacking shaft, and the other end is hinged to the stacking plate, the stacking plate will be subjected to force and make a piston-like reciprocating motion in the inner cavity of the stacking tank along the length of the stacking tank. This causes the sodium sulfite particles falling from the conveying tank into the inner cavity of the stacking tank to be scraped and pushed into a stack by the stacking plate, and finally transported to the stacking packaging system to complete the packaging. The simultaneous stacking and packaging of sodium sulfite during recovery reduces equipment energy consumption and improves the efficiency of collection and packaging. Attached Figure Description

[0019] Figure 1 This is a schematic flow chart of a process for extracting sodium sulfite from sodium desulfurization products according to the present invention. Figure 1 ; Figure 2 This is a schematic flow chart of a process for extracting sodium sulfite from sodium desulfurization products according to the present invention. Figure 2 ; Figure 3 This is a schematic diagram of the overall structure of a dust removal device for extracting sodium sulfite products after sodium desulfurization according to the present invention. Figure 4 This is a schematic cross-sectional view of a dust removal device for extracting sodium sulfite after sodium desulfurization according to the present invention. Figure 5This is a schematic cross-sectional view of a container assembly for a dust removal device used in the post-treatment of sodium desulfurization to extract sodium sulfite products according to the present invention. Figure 6 This is a schematic diagram of the filter assembly structure of a dust removal device for extracting sodium sulfite products after sodium desulfurization according to the present invention. Figure 7 This is a schematic diagram of the assembly of the filter components and rotating rod of a dust removal device for extracting sodium sulfite products after sodium desulfurization according to the present invention. Figure 8 This is a schematic diagram of the filter assembly of a dust removal device for extracting sodium sulfite after sodium desulfurization according to the present invention. Figure 9 This is a schematic diagram of the film transfer component structure of a dust removal device for extracting sodium sulfite products after sodium desulfurization according to the present invention; Figure 10 This is a schematic diagram of the knocking component structure of a dust removal device for extracting sodium sulfite products after sodium desulfurization according to the present invention. Figure 11 This is a schematic diagram of the stacking assembly structure of a dust removal device for extracting sodium sulfite products after sodium desulfurization according to the present invention. Figure 12 This is a partial cross-sectional schematic diagram of a dust removal device for extracting sodium sulfite products after sodium desulfurization according to the present invention. Figure 1 .

[0020] The attached figures are labeled as follows: 100. Container assembly; 101. Filter tank; 1011. Fixing ring; 102. Collection tank; 103. Conveying tank; 104. Stacking tank; 105. Shell; 106. Base; 107. Inlet pipe; 108. Outlet pipe; 200. Filter assembly; 201. Support; 202. Filter membrane; 203. Ear plate; 204. Impact assembly; 2041. Mounting plate; 2042. Impact shaft; 2043. Hammer rod; 2044. Hammer head; 2045. Push rod; 205. Mounting slot; 206. Mounting post; 207. Membrane transfer assembly; 2071. Sector; 2072. Torsion spring rod; 2073. Membrane fixing post; 300. Stacking assembly; 301. Rotating rod; 302. First lever; 303. First gear; 304. Second gear; 305. Motor; 306. Fixing plate; 307. Stacking shaft; 308. First connecting rod; 309. Second connecting rod; 310. Stacking plate; 311. Second lever; 1. Desulfurization mother liquor tank; 2. Desulfurization mother liquor pump; 3. Cyclone separator; 4. Integrated centrifuge for concentration and filtration; 5. Filtrate tank; 6. Filtrate pump; 7. Fluidized bed dryer; 8. Dust removal device for extracting sodium sulfite products after sodium desulfurization. Detailed Implementation

[0021] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to embodiments. Of course, the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0022] Although the steps in this invention are arranged by reference numerals, this is not intended to limit the order of the steps. Unless the order of the steps is explicitly stated or the execution of a step requires other steps as a basis, the relative order of the steps can be adjusted. It is understood that the term "and / or" as used herein refers to and covers any and all possible combinations of one or more of the associated listed items.

[0023] Example like Figures 1-2 As shown, a process for extracting sodium sulfite from sodium desulfurization products includes the following steps: S101: The saturated desulfurization mother liquor absorbed in the desulfurization unit is transported to the desulfurization mother liquor tank 1 by the slurry discharge pump. A certain concentration of sodium hydroxide solution is added to the desulfurization mother liquor tank 1, and a certain amount of sodium sulfite crystals are precipitated by reaction and crystallization. S102: The slurry that has precipitated a certain amount of crystals is transported to the hydrocyclone 3 by the desulfurization mother liquor pump 2. Solid-liquid pre-separation is carried out in the hydrocyclone 3. The bottom slurry flows by gravity to the concentration and filtration centrifuge 4, and the supernatant flows by gravity to the filtrate tank 5. S103: Add a certain amount of antioxidant to the filtrate tank 5, mix it evenly with the clear liquid, and then send it to the desulfurization tower slurry via the filtrate pump 6 for recycling, while inhibiting the oxidation of sodium sulfite in the tower. S104: The concentrated phase flows to the integrated centrifuge 4 for concentration and filtration. It is deeply dehydrated in the integrated centrifuge 4. After most of the water is removed, the product enters the fluidized bed dryer 7. After preheating, drying and cooling in the fluidized bed dryer 7, anhydrous sodium sulfite product is obtained. S105: The dried anhydrous sodium sulfite product is conveyed for stacking and packaging. The exhaust gas discharged from the fluidized bed dryer 7 enters the dust removal device 8 used for sodium desulfurization post-treatment to extract sodium sulfite product, and the sodium sulfite product entrained in the gas is separated and recovered. S106: The separated and recovered sodium sulfite product is transported to stacking and packaging. The exhaust gas after dust removal is returned to the desulfurization tower for flue gas purification treatment, so as not to generate secondary pollution.

[0024] In the above process, the salting-out crystallization principle is adopted. Compared with evaporation crystallization, the process flow is shorter, the operation is simpler, the energy consumption is lower, and the operating cost is lower. The supernatant from solid-liquid separation is returned to the tower for recycling, and the drying tail gas is returned to the desulfurization tower for treatment. The entire process does not generate secondary pollution. A special centrifuge for sodium sulfite is used, which overcomes the shortcomings of conventional centrifuges, such as strict requirements on mother liquor, intermittent feeding and discharging, and inability to operate continuously. It has the characteristics of wide adaptability to mother liquor solid content and particle size, good solid-liquid separation effect, and low product moisture content. It can produce continuously and stably, improving the stability and capacity of the system. An antioxidant system is added, with organic antioxidants added to the slurry to inhibit the oxidation of sodium sulfite and sodium bisulfite, improving product quality. The added antioxidants are all organic substances, which are easily separated in subsequent drying processes and do not affect product quality.

[0025] It is worth noting that a certain amount of antioxidant is added to the filtrate tank 5, and after being mixed evenly with the clear liquid, it is pumped to the desulfurization tower slurry for recycling, while inhibiting the oxidation of sodium sulfite in the tower. The desulfurization mother liquor is a mixed solution of sodium bisulfite and sodium sulfite, which can have a certain solid content. The desulfurization mother liquor tank 1 utilizes the differences in solubility and reaction characteristics of sodium bisulfite, sodium sulfite, and sodium hydroxide to react and crystallize sodium sulfite crystals. The concentration of the sodium hydroxide solution added to the desulfurization mother liquor tank 1 can be selected according to the solid content and concentration of the desulfurization mother liquor. The solid content of the concentrated phase in the lower layer of the hydrocyclone 3 can reach 15%~50%. The antioxidant added to the filtrate tank 5 can be organic substances such as hydroquinone, p-phenylenediamine, and ethylenediaminetetraacetic acid.

[0026] A dust removal device 8 for use in the above-mentioned industrial method for extracting sodium sulfite products after sodium desulfurization includes a container assembly 100. The container assembly 100 includes a filter tank 101, a collection tank 102, a conveying tank 103, and a stacking tank 104, which are fixedly connected and communicated from top to bottom. The inner cavity of the filter tank 101 is connected to an air inlet pipe 107 and an air outlet pipe 108. The inner cavity of the filter tank 101 houses filter components 200 arranged side by side. The air inlet pipe 107 communicates with the bottom of the inner cavity of the filter tank 101, and the air outlet pipe 108 communicates with the bottom of the inner cavity of the filter tank 101. One end of the stacking tank 104 is fixedly connected to a stacking assembly 300. The stacking assembly 300 is configured such that when the motor 305 is started, it scrapes and pushes the particles falling into the inner cavity of the stacking tank 104 toward the other end of the stacking tank 104.

[0027] Furthermore, the filter assembly 200 includes a support 201, which is fixedly connected to a fixing ring 1011 corresponding to the inner wall of the filter tank 101, and a filter membrane 202 is placed at the bottom of the support 201. The stacking assembly 300 includes a rotating rod 301, which passes through the center of the collection tank 102. The lower end of the rotating rod 301 located outside the collection tank 102 is connected to a motor 305 for transmission, and the upper end of the rotating rod 301 located inside the cavity of the filter tank 101 is fixedly connected to the center of multiple filter assemblies 200.

[0028] Furthermore, multiple pairs of ear plates 203 are fixedly connected to the bracket 201, and an installation groove 205 is provided between each pair of ear plates 203; The upper part of the rotating rod 301 is fixedly connected to one end of the filter tank 101, which is located in the inner cavity of the filter tank 101. Each first lever 302 is located above a corresponding filter component 200. When the first lever 302 rotates, it moves the striking component 204 to strike the filter membrane 202.

[0029] Furthermore, the striking assembly 204 includes a mounting plate 2041, with a striking shaft 2042 fixedly connected to the center of the mounting plate 2041. The two ends of the striking shaft 2042 are rotatably connected to a pair of ear plates 203 on both sides of the mounting groove 205. A hammer rod 2043 and a push rod 2045 are fixedly connected to the arc surface of the mounting plate 2041. A hammer head 2044 is fixedly connected to the end of the hammer rod 2043 away from the mounting plate 2041, and the hammer head 2044 faces the filter membrane 202. When the first lever 302 rotates, it contacts the push rod 2045.

[0030] In this invention, unextracted sodium sulfite still entrained in the waste gas after drying and separation can be fully extracted and recovered, improving resource utilization efficiency. Even after drying and sodium sulfite extraction, the waste gas still contains some floating sodium sulfite particles. This portion of the waste gas enters the lower part of the inner cavity of the filter tank 101 through the inlet pipe 107. Because the outlet pipe 108 is located at the top of the filter tank 101, the waste gas will float upwards within the inner cavity of the filter tank 101. During this floating process, it will sequentially pass through the filter membrane 202 fixed to the filter assembly 200 within the inner cavity of the filter tank 101. Under the filtration and adsorption effect of the filter membrane 202, the sodium sulfite particles entrained in the waste gas will be adsorbed onto the filter membrane 202. Furthermore, because the first lever 302 fixedly connected to the rotating rod 301 rotates together with the motor 305 when it starts, the first lever 302 rotates... The push rod 2045 on the striking component 204 is activated. After the push rod 2045 is subjected to force, it drives the mounting plate 2041 to rotate along the striking shaft 2042, thereby driving and lifting the hammer rod 2043 and hammer head 2044 fixed on the mounting plate 2041. After the first lever 302 is disengaged and no longer in contact with the push rod 2045, the hammer head 2044 falls down under its own gravity and strikes the filter membrane 202. As the first lever 302 rotates back and forth, the filter membrane 202 is also continuously struck by multiple striking components, causing the sodium sulfite particles attached to the filter membrane to be shaken off. The fallen sodium sulfite particles will pass through the filter tank 101, the collection tank 102, and the transfer tank 103 in sequence before falling into the inner cavity of the stacking tank 104. Finally, under the operation of the stacking component, the stacking and packaging are completed, realizing the recovery and extraction of sodium sulfite entrained in the exhaust gas and improving resource utilization efficiency.

[0031] It is worth noting that three filter membranes 202 are arranged sequentially in the inner cavity of the filter tank 101, with the pores getting smaller from bottom to top. This allows sodium sulfite particles falling from the upper filter membrane 202 to easily pass through the lower filter membrane 202. Moreover, the collection tank 102 is a funnel shape that is wider at the top and narrower at the bottom, which facilitates the smoother collection of the falling sodium sulfite particles into the conveying tank 103.

[0032] Furthermore, the filter assembly 200 includes a mounting post 206, which is fixedly connected to the bottom center of the support 201. A membrane transfer assembly 207 is rotatably connected to the outer wall of the mounting post 206. The membrane transfer assembly includes a fan-shaped body 2071, on which a torsion spring rod 2072 is fixedly connected. The torsion spring rod 2072 extends in the direction away from the support 201. Multiple membrane fixing posts 2073 are arranged circumferentially on the side of the fan-shaped body 2071 facing the support 201. The filter membrane 202 is fixedly connected to the membrane fixing posts 2073. Multiple second levers 302 are fixedly connected to the rotating rod 301. Each second lever 302 is located under the corresponding membrane assembly 207. When the second lever 302 rotates, it will collide with the torsion spring rod 2072.

[0033] In this invention, sodium sulfite extraction can simultaneously clean the filter membrane thoroughly, reducing the frequency of filter membrane replacement. This is because the mounting column 206 is fixedly connected to the bottom center of the support 201, and the fan-shaped body 2071 of the membrane transfer assembly 207 is rotatably connected to the outer wall of the mounting column 206. The fan-shaped body 2071 is located between the bottom ring of the mounting column 206 and the bottom surface of the support 201, with a gap between the fan-shaped body 2071 and the bottom surface of the support 201 for placing the filter membrane 202. The filter membrane 202 is fixedly connected to the membrane fixing column 2073 on the top surface of the fan-shaped body 2071. Therefore, the filter membrane 202 will rotate with the fan-shaped body 2071. At this time, the support 201 is fixedly connected to the corresponding fixing ring 1011 on the inner wall of the filter tank 101, and the support 201 will not rotate. Furthermore, because the second lever 302 fixedly connected to the rotating rod 301 rotates with the rotating rod 301, it will interact with the fan-shaped body... The torsion spring rod 2072, which is fixedly connected to the side of 2071, collides with the filter membrane 202. The torsion spring rod 2072, under the force, drives the sector body 2071 and the filter membrane 202 to rotate. At the same time, the torsion spring rod 2072 rotates under the action of the torsion spring until it separates from the second lever 302 and no longer contacts it. Then, the torsion spring rod 2072 returns to its original position under the action of the torsion spring, and the rotation of the sector body 2071 and the filter membrane 202 slows down. This makes the rotation speed of the first lever 302 on the rotating rod 301 and the filter membrane 202 inconsistent. The first lever 302 moves the striking component 204 to strike the filter membrane 202, so the striking point will change constantly. It can also ensure that the striking point can cover every circumferential angle on the filter membrane 202. Therefore, the filter membrane 202 can be thoroughly cleaned, reducing the frequency of filter membrane 202 replacement and maintenance, and avoiding the economic losses caused by frequent equipment downtime due to excessive frequency of filter membrane 202 replacement.

[0034] It is worth noting that the ring at the bottom of the mounting post 206 of the sector-shaped body 2071 is detachable, which makes it convenient to remove the filter membrane 202 together with the sector-shaped body 2071 when replacing the filter membrane 202.

[0035] Furthermore, the stacking assembly 300 includes a first gear 303, which is located between the collection tank 102 and the motor 305 and is fixedly connected to the rotating rod 301. A second gear 304 meshes with the first gear 303 and is fixedly connected to one end of the stacking rotating shaft 307. The other end of the stacking rotating shaft 307 is rotatably connected to one end of the first connecting rod 308. The other end of the first connecting rod 308 is rotatably connected to one end of the second connecting rod 309. The other end of the second connecting rod 309 is hinged to one side of the stacking plate 310.

[0036] Furthermore, the stacking assembly 300 includes a fixing plate 306, which is fixedly connected to the outer wall of the stacking tank 104, a motor 305 is fixedly connected to the fixing plate 306, and a stacking shaft 307 is rotatably fixed to the fixing plate 306.

[0037] This invention, while driving the striking component to separate and recover sodium sulfite, also simultaneously drives the stacking component to stack and package the sodium sulfite, reducing equipment energy consumption and improving the efficiency of both collection and packaging operations. When the motor 305 starts, it drives the rotating rod 301 to rotate, causing the striking component to strike the filter membrane 202 to separate the sodium sulfite. Simultaneously, the first gear 303 fixedly connected to the rotating rod 301 also rotates, driving the second gear 304, which meshes with the first gear 303, to rotate. The second gear 304, in turn, drives the first connecting rod 308, connected to the stacking shaft 307, to rotate. Furthermore, because one end of the second connecting rod 309 is rotatably connected to the end of the first connecting rod 308 away from the stacking shaft 307, and the other end is hinged to the stacking plate 310, the stacking plate 310 will be subjected to force and make a piston-like reciprocating motion along the length of the stacking tank 104 in the inner cavity of the stacking tank 104. This causes the sodium sulfite particles falling from the conveying tank 103 into the inner cavity of the stacking tank 104 to be scraped and pushed into a stack by the stacking plate 310, and finally transported to the stacking packaging system to complete the packaging. Stacking and packaging are carried out simultaneously when recovering sodium sulfite, which reduces equipment energy consumption and improves the efficiency of collection and packaging.

[0038] Furthermore, the container assembly 100 includes a housing 105, which is detachably connected to the collection tank 102 and the delivery tank 103. The cavity formed by the inner wall of the housing 105, the outer wall of the lower inclined surface of the collection tank 102, and the side of the delivery tank 103 near the stacking assembly 300 houses the first gear 303, the second gear 304, and the motor 305.

[0039] In this invention, since the working environment of the device is a dusty place, a cover 105 is set outside the first gear 303, the second gear 304 and the motor 305 to effectively prevent them from being blocked by dust and affecting the operation of the device. The cover 105 can be detached and installed to facilitate the subsequent maintenance of the only power source motor 305 in the device by the workers.

[0040] Furthermore, the container assembly 100 includes a base 106, which is fixedly connected to and communicates with the stacking tank 104, and the first connecting rod 308 is housed in the inner cavity of the base 106.

[0041] Furthermore, the filter tank 101 includes a plurality of fixing rings 1011, which are fixed side by side on the inner wall of the filter tank 101 along the length of the central axis of the filter tank 101, and each filter assembly 200 is fixedly connected to a corresponding bracket 201.

[0042] The above description is only a preferred embodiment of the present invention. It should be noted that those skilled in the art can make several improvements and modifications without departing from the inventive concept of the present invention, and these all fall within the protection scope of the present invention.

Claims

1. A process for extracting sodium sulfite from sodium desulfurization products, characterized in that, Includes the following steps: S101: The saturated desulfurization mother liquor absorbed in the desulfurization unit is transported to the desulfurization mother liquor tank (1) by the slurry discharge pump. A certain concentration of sodium hydroxide solution is added to the desulfurization mother liquor tank (1), and a certain amount of sodium sulfite crystals are precipitated by reaction crystallization. S102: The slurry that has precipitated a certain amount of crystals is transported to the hydrocyclone (3) by the desulfurization mother liquor pump (2). Solid-liquid pre-separation is carried out in the hydrocyclone (3). The bottom slurry flows by gravity to the integrated centrifuge for concentration and filtration (4), and the supernatant flows by gravity to the filter tank (5). S103: Add a certain amount of antioxidant to the filtrate tank (5), mix it evenly with the clear liquid, and then pump it to the desulfurization tower slurry for recycling, while inhibiting the oxidation of sodium sulfite in the tower; S104: The concentrated phase flows to the integrated centrifuge (4) for concentration and filtration. The product is deeply dehydrated in the integrated centrifuge (4). After most of the water is removed, the product enters the fluidized bed dryer (7). After preheating, drying and cooling in the fluidized bed dryer (7), anhydrous sodium sulfite product is obtained. S105: The dried anhydrous sodium sulfite product is transported for stacking and packaging. The exhaust gas discharged from the fluidized bed dryer (7) enters the dust removal device (8) used for sodium desulfurization post-treatment to extract sodium sulfite products, and the sodium sulfite products entrained in the gas are separated and recovered. S106: The separated and recovered sodium sulfite product is transported to stacking and packaging. The exhaust gas after dust removal is returned to the desulfurization tower for flue gas purification treatment, so as not to generate secondary pollution.

2. The dust removal device (8) for extracting sodium sulfite products after sodium desulfurization as described in claim 1, characterized in that, The dust removal device (8) includes a container assembly (100), which includes a filter tank (101), a collection tank (102), a conveying tank (103), and a stacking tank (104) that are fixedly connected and communicated from top to bottom. The inner cavity of the filter canister (101) is connected to an air inlet pipe (107) and an air outlet pipe (108). The inner cavity of the filter canister (101) contains filter components (200) arranged side by side. The air inlet pipe (107) is connected to the bottom of the inner cavity of the filter canister (101), and the air outlet pipe (108) is connected to the bottom of the inner cavity of the filter canister (101). One end of the stacking tank (104) is fixedly connected to a stacking assembly (300), which is configured to scrape and push the particles falling into the inner cavity of the stacking tank (104) toward the other end of the stacking tank (104) when the motor (305) is started.

3. The dust removal device (8) for extracting sodium sulfite products after sodium desulfurization as described in claim 2, characterized in that, The filter assembly (200) includes a bracket (201), which is fixedly connected to a fixing ring (1011) on the inner wall of the filter tank (101), and a filter membrane (202) is placed at the bottom of the bracket (201). The stacking assembly (300) includes a rotating rod (301) that passes through the center of the collection tank (102). The lower end of the rotating rod (301) located outside the collection tank (102) is connected to the motor (305) for transmission, and the upper end of the rotating rod (301) located inside the filter tank (101) is fixedly connected to the center of a plurality of filter assemblies (200).

4. The dust removal device (8) for extracting sodium sulfite products after sodium desulfurization as described in claim 3, characterized in that, Multiple pairs of ear plates (203) are fixedly connected to the bracket (201), and an installation groove (205) is provided between each pair of ear plates (203). The upper part of the rotating rod (301) is fixedly connected to a plurality of first levers (302) in the inner cavity of the filter tank (101). Each first lever (302) is located above a corresponding filter assembly (200). When the first lever (302) rotates, it actuates the striking assembly (204) to strike the filter membrane (202).

5. The dust removal device (8) for extracting sodium sulfite after sodium desulfurization as described in claim 4, characterized in that, The striking assembly (204) includes a mounting plate (2041), the center of which is fixedly connected to a striking shaft (2042), and the two ends of the striking shaft (2042) are rotatably connected to a pair of ear plates (203) on both sides of the mounting groove (205); A hammer rod (2043) and a push rod (2045) are fixedly connected to the arc surface of the mounting plate (2041). The hammer rod (2043) is fixedly connected to a hammer head (2044) at the end away from the mounting plate (2041). The hammer head (2044) faces the filter membrane (202). When the first lever (302) rotates, it touches the push rod (2045).

6. The dust removal device (8) for extracting sodium sulfite products after sodium desulfurization as described in claim 3, characterized in that, The filter assembly (200) includes a mounting post (206), which is fixedly connected to the bottom center of the bracket (201), and a membrane transfer assembly (207) is rotatably connected to the outer wall of the mounting post (206). The membrane transfer assembly includes a fan-shaped body (2071), on which a torsion spring rod (2072) is fixedly connected. The torsion spring rod (2072) extends in the direction away from the support (201). Multiple membrane fixing columns (2073) are arranged circumferentially on the side of the fan-shaped body (2071) facing the support (201). The filter membrane (202) is fixedly connected to the membrane fixing columns (2073). Multiple second levers (302) are fixedly connected to the rotating rod (301). Each second lever (302) is located on the lower side of the corresponding membrane module (207). When the second lever (302) rotates, it will collide with the torsion spring rod (2072).

7. The dust removal device (8) for extracting sodium sulfite products after sodium desulfurization as described in claim 3, characterized in that, The stacking assembly (300) includes a first gear (303), which is located between the collection tank (102) and the motor (305) and is fixedly connected to the rotating rod (301). A second gear (304) meshes with the first gear (303) and is fixedly connected to one end of the stacking shaft (307). The other end of the stacking shaft (307) is rotatably connected to one end of the first connecting rod (308). The other end of the first connecting rod (308) is rotatably connected to one end of the second connecting rod (309). The other end of the second connecting rod (309) is hinged to one side of the stacking plate (310).

8. The dust removal device (8) for extracting sodium sulfite products after sodium desulfurization as described in claim 7, characterized in that, The stacking assembly (300) includes a fixing plate (306), which is fixedly connected to the outer wall of the stacking tank (104), a motor (305) is fixedly connected to the fixing plate (306), and a stacking shaft (307) is rotatably fixed to the fixing plate (306).

9. The dust removal device (8) for extracting sodium sulfite products after sodium desulfurization as described in claim 7, characterized in that, The container assembly (100) includes a housing (105) which is detachably connected to the collection tank (102) and the delivery tank (103). The cavity formed by the inner wall of the housing (105), the outer wall of the lower slope of the collection tank (102), and the side of the delivery tank (103) near the stacking assembly (300) houses the first gear (303), the second gear (304), and the motor (305).

10. The dust removal device (8) for extracting sodium sulfite products after sodium desulfurization as described in claim 7, characterized in that, The container assembly (100) includes a base (106) which is fixedly connected to and communicates with the stacking tank (104), and the first connecting rod (308) is housed in the inner cavity of the base (106).

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