Ammonia-process flue gas desulfurization device
The ammonia-based flue gas desulfurization device, which uses multi-stage filtration and crystallization, solves the problem of incomplete flue gas purification, achieves high-efficiency desulfurization and high-yield ammonium sulfate, and reduces production costs.
Patent Information
- Application Number
- CN202520013137.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-01-03
- Publication Date
- 2026-02-10
- Estimated Expiration
- 2035-01-03
AI Technical Summary
Existing ammonia-based desulfurization units do not thoroughly purify flue gas, which can easily lead to ammonia escape, resulting in low desulfurization efficiency, low ammonium sulfate production, and high production costs.
The desulfurization tower adopts a multi-stage filtration and oxidation section, a concentration and crystallization section, an absorption section, and a demisting section. Combined with spray pipes, an electrostatic precipitator, and a circulating crystallizer, the flue gas is treated through multiple countercurrent contact and crystallization processes to form ammonium sulfite and ammonium sulfate, preventing ammonia escape and increasing ammonium sulfate production.
It achieves complete purification of flue gas, improves desulfurization efficiency, prevents ammonia escape, reduces production costs, and increases ammonium sulfate production.
Smart Images
Figure CN223887737U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The application relates to the technical field of chemical raw material production, in particular to an ammonia flue gas desulfurization device. BACKGROUND
[0002] In industrial production, acid gas harmful substances contained in tail gas flue gas, especially SO2, are the main source of acid rain.
[0003] In the prior art, the method for solving acid rain pollution is usually flue gas desulfurization. Ammonia is used as raw material, and the desulfurization product is ammonium sulfate, which is a kind of chemical fertilizer with high fertilizer efficiency. The unit compound fertilizer efficiency is higher than that of urea, and the sulfur element in the compound fertilizer is also a necessary nutrient element for the growth of crops.
[0004] However, the existing ammonia desulfurization device cannot completely purify flue gas, which is easy to cause ammonia escape, needs repeated purification, has low desulfurization efficiency, and makes the yield of the product ammonium sulfate after flue gas desulfurization low and the production cost high, and therefore has defects. CONTENT OF THE UTILITY MODEL
[0005] In order to make up for the above defects, the utility model provides an ammonia flue gas desulfurization device which can completely purify flue gas, avoid ammonia escape, has high desulfurization efficiency and reduces production cost.
[0006] The application is implemented as follows:
[0007] A preliminary filter is fixedly connected with a desulfurization tower body, the desulfurization tower body is divided into an oxidation section, a concentration crystallization section, an absorption section and a demisting section from bottom to top, the preliminary filter is fixedly connected with the concentration crystallization section, a top end of the desulfurization tower body is connected with an electric dust collector, a spraying pipeline is arranged between the oxidation section and the absorption section, the concentration crystallization section is fixedly connected with a circulating crystallizer, and a bottom end of the circulating crystallizer is fixedly connected with a bottom part of the oxidation section.
[0008] In an embodiment of the application, an oxygen generator and a liquid nitrogen pump are installed at the oxidation section.
[0009] In an embodiment of the application, a first spraying pipe is arranged at the concentration crystallization section, and the first spraying pipe is connected with an upper end of the circulating crystallizer.
[0010] In an embodiment of the application, a filter inclined plate is arranged at the bottom part of the concentration crystallization section, and an inclined tail end of the filter inclined plate is fixedly connected with a bottom end of the circulating crystallizer.
[0011] In an embodiment of the application, a crystallization conveying pump is arranged at a connecting pipeline of the filter inclined plate and the circulating crystallizer.
[0012] In an embodiment of the present application, a plurality of spray pipes are arranged at the absorption section and fixedly communicated with the oxidation section.
[0013] In an embodiment of the present application, the demisting section comprises a filler layer, a water spray pipe and a demister, the filler layer is arranged above the absorption section, the water spray pipe is arranged above the filler layer, and the demister is installed above the water spray pipe.
[0014] In an embodiment of the present application, a discharge pump is arranged on a pipeline connecting the bottom end of the oxidation section with the bottom end of the circulating crystallizer.
[0015] In an embodiment of the present application, a stirrer is arranged in the middle and lower part of the circulating crystallizer.
[0016] The beneficial effects of the present application are as follows: the tail gas formed after industrial production enters the preliminary filter, is preliminarily filtered by the preliminary filter to form primary flue gas, the temperature is high at this time, and the primary flue gas enters the desulfurization tower body and is in the concentration crystallization section, is cooled by the spray in the concentration crystallization section, and continues to rise, at this time, the ammoniation mixed solution is transported to the absorption section through the oxidation section, in the absorption section, the primary flue gas after cooling is in countercurrent contact with the sprayed ammoniation mixed solution to perform a desulfurization reaction, at this time, SO in the flue gas is absorbed to form ammonium sulfite, the flue gas continues to rise to the demisting section, the ammoniacal liquid and water mist in the flue gas are intercepted in the demisting section, and the flue gas containing only a small amount of small particles and aerosol is obtained, at this time, the small particles and aerosol are further removed by the electric dust collector, the flue gas meets the national tail gas emission standard, and the flue gas is discharged into the atmosphere; meanwhile, in the process of purifying the flue gas, the ammonium sulfite formed by the flue gas in the absorption section flows into the oxidation section to form ammonium sulfate solvent, when the content of ammonium sulfate solvent in the ammoniation mixed solution is high, the mixed solution is transported to the circulating crystallizer to perform crystallization, and the crystallization in the circulating crystallizer starts from the bottom, so that the upper solution in the circulating crystallizer is still the ammoniation mixed solution containing dilute ammonium sulfate, the part of the solution is transported to the concentration crystallization section to preliminarily cool and preliminarily desulfurize the flue gas, wherein, due to the cooling of the hot flue gas, the ammoniation mixed solution containing dilute ammonium sulfate evaporates, thereby forming a small amount of ammonium sulfate crystals, the small amount of ammonium sulfate crystals is transported back to the circulating crystallizer through the concentration crystallization section to perform comprehensive crystallization, and then the solid-containing filtrate is transported to the next process to form ammonium sulfate, thereby improving the yield of ammonium sulfate, the desulfurization efficiency of the device is high, the flue gas can be thoroughly purified at one time, the escape of the ammoniation liquid from the desulfurization tower body can be prevented, the ammoniation mixed solution can be fully utilized, the yield of ammonium sulfate is improved, and the production cost is reduced, thereby solving the problems in the prior art, such as incomplete flue gas purification, easy ammonia escape, the need for repeated purification, low desulfurization efficiency, low yield of ammonium sulfate after flue gas desulfurization, and high production cost. Attached Figure Description
[0017] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this utility model and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained from these drawings without creative effort.
[0018] Fig. 1 A schematic diagram of an ammonia-based flue gas desulfurization device is provided for embodiments of this application;
[0019] Fig. 2 A flowchart of an ammonia-based flue gas desulfurization device is provided for embodiments of this application;
[0020] In the diagram: 1-Preliminary filter; 2-Desulfurization tower body; 21-Oxidation section; 22-Concentration and crystallization section; 23-Absorption section; 24-Demisting section; 241-Packing layer; 242-Water spray pipe; 243-Demister; 25-Spray pipe; 26-First spray pipe; 27-Filter inclined plate; 28-Multi-layer spray pipe; 29-Crystallization conveying pump; 3-Electrostatic precipitator; 4-Circulating crystallizer; 5-Oxygen generator; 6-Liquid nitrogen pump; 7-Discharge pump; Detailed Implementation
[0021] The following detailed description, in conjunction with the accompanying drawings, outlines some embodiments of the present invention. Unless otherwise specified, the following embodiments and features can be combined with each other.
[0022] like Figs. 1-2 As shown, an ammonia-based flue gas desulfurization device according to an embodiment of this application includes:
[0023] The preliminary filter 1 is fixedly connected with the desulfurization tower body 2, the desulfurization tower body 2 is divided into an oxidation section 21, a concentration crystallization section 22, an absorption section 23 and a demisting section 24 from bottom to top, and the preliminary filter 1 is fixedly connected with the concentration crystallization section 22, the top end of the desulfurization tower body 2 is connected with an electric dust collector 3, a spray pipeline 25 is arranged between the oxidation section 21 and the absorption section 23, the concentration crystallization section 22 is fixedly connected with a circulating crystallizer 4, and the bottom end of the circulating crystallizer 4 is fixedly connected with the bottom of the oxidation section 21. It should be noted that the initial circulating crystallizer 4 is provided with a solid-liquid cooling mixture containing ammonia and ammonium sulfate, which is used for cooling and preliminary desulfurization of hot flue gas in the concentration crystallization section 22. The tail gas flue gas formed after industrial production enters the preliminary filter 1, and after the large particle dust is preliminarily filtered by the preliminary filter 1, the preliminary flue gas is formed, at this time, the temperature is high, and the preliminary flue gas enters the desulfurization tower body 2 and is in the concentration crystallization section 22. After being cooled by the concentration crystallization section 22, it continues to rise, at this time, the ammoniation mixed solution is transported to the absorption section 23 through the oxidation section 21, in the absorption section 23, the cooled preliminary flue gas is countercurrently contacted with the sprayed ammoniation mixed solution to carry out desulfurization reaction, at this time, SO2 in the flue gas is absorbed to form ammonium sulfite, the flue gas continues to rise to the demisting section 24, and the ammonium liquid and water mist in the flue gas are intercepted through the demisting section 24, so that the flue gas containing only a small amount of small particles and aerosol is obtained. At this time, the electric dust collector 3 is further used for removing small particles and aerosol, so that the flue gas meets the national tail gas emission standard, and the flue gas is discharged into the atmosphere; meanwhile, in the process of purifying the flue gas, the ammonium sulfite formed by the flue gas passing through the absorption section 23 flows into the oxidation section 21 to form an ammonium sulfate solvent, when the content of the ammonium sulfate solvent in the ammoniation mixed solution is high, the mixed solution is transported to the circulating crystallizer 4 for crystallization, and the upper layer solution in the circulating crystallizer 4 is still the ammoniation mixed solution containing dilute ammonium sulfate during crystallization in the circulating crystallizer 4, so that the solution is transported to the concentration crystallization section 22 to preliminarily cool the flue gas and preliminarily desulfurize the flue gas. Due to the cooling of the hot flue gas, the ammoniation mixed solution containing dilute ammonium sulfate evaporates, so that a small amount of ammonium sulfate crystals are formed, the small amount of ammonium sulfate crystals are transported back to the circulating crystallizer 4 through the concentration crystallization section 22 for comprehensive crystallization, and then the solid-containing filtrate is transported to the next process to form ammonium sulfate, so that the yield of ammonium sulfate is improved, the desulfurization efficiency of the device is high, the flue gas can be thoroughly purified at one time, the ammoniation liquid can be prevented from escaping from the desulfurization tower body 2, the ammoniation mixed solution can be fully utilized, the yield of ammonium sulfate is improved, and the production cost is reduced. The problems that the flue gas is not thoroughly purified in the prior art, the ammonia escapes easily, repeated purification is needed, the desulfurization efficiency is low, the yield of ammonium sulfate after flue gas desulfurization is low, and the production cost is high are solved.
[0024] Further, the oxidation section 21 is provided with an oxygen generator 5 and a liquid nitrogen pump 6. The liquid nitrogen pump 6 is used to input liquid nitrogen into the oxidation section 21, and the oxygen generator 5 is used to oxidize the ammonium sulfite formed by the flue gas desulfurization into stable ammonium sulfate when the ammonium sulfite falls into the oxidation section 21.
[0025] Further, the concentration and crystallization section 22 is provided with a first spray pipe 26 connected to the upper end of the circulating crystallizer 4. The first spray pipe 26 is connected to the circulating crystallizer 4 and is used to spray the upper layer of the ammoniated mixed solution containing dilute ammonium sulfate in the circulating crystallizer 4, so that the flue gas and the ammoniated mixed solution contact in countercurrent, and the flue gas is preliminarily desulfurized while being cooled, and the ammoniated mixed solution containing dilute ammonium sulfate is desulfurized with ammonia to form ammonium sulfite flowing into the oxidation section 21. Due to the evaporation effect of the hot flue gas, the ammonium sulfate in the ammoniated mixed solution containing dilute ammonium sulfate is crystallized to form small crystals.
[0026] Further, the bottom of the concentration and crystallization section 22 is provided with a filter inclined plate 27, and the inclined tail end of the filter inclined plate 27 is fixedly connected to the bottom end of the circulating crystallizer 4. The small ammonium sulfate crystals formed by spraying in the concentration and crystallization section 22 are filtered by the filter inclined plate 27 to prevent the small crystals from falling into the oxidation section 21.
[0027] Further, the connecting pipeline between the filter inclined plate 27 and the circulating crystallizer 4 is provided with a crystallization conveying pump 29. After the small ammonium sulfate crystals are collected by the filter inclined plate 27, they are conveyed to the bottom of the circulating crystallizer 4 by the crystallization conveying pump 29, and gradually crystallized into large crystals that can meet the production and use standards by the circulating crystallizer 4.
[0028] Further, the absorption section 23 is provided with a plurality of spray pipes 28 fixedly connected to the oxidation section 21. The ammoniated mixed solution in the oxidation section 21 is uniformly sprayed out by the plurality of spray pipes 28 to contact with the flue gas in countercurrent, and the flue gas is desulfurized to ensure that the SO2 in the flue gas is completely removed.
[0029] Further, the demisting section 24 includes a filler layer 241, a water spray pipe 242, and a demister 243. The filler layer 241 is arranged above the absorption section 23, the water spray pipe 242 is arranged above the filler layer 241, and the demister 243 is arranged above the water spray pipe 242. The flue gas after the desulfurization reaction contains a large amount of water and a small amount of unabsorbed ammonia. The flue gas is distributed more uniformly by the filler layer 241, and then a large amount of water mist is formed by the water spray pipe 242 to trap the escaped ammonia, so that the ammonia is further removed and the ammonia loss is reduced. At this time, the flue gas passes through the demister 243 to remove the water, so that the water content in the flue gas is reduced.
[0030] Further, the bottom end of the oxidation section 21 is connected with the bottom end of the circulating crystallizer 4, and a discharge pump 7 is arranged on the pipeline. When the ammonia mixed solution in the oxidation section 21 is recycled, the ammonium sulfite formed in the concentration crystallization section 22 and the absorption section 23 continuously enters the oxidation section 21, and the ammonium sulfite is continuously formed into an ammonium sulfate solvent through the oxidation of the oxidation section 21, so that the concentration of the ammonium sulfate in the ammonia mixed solution is continuously increased. When the concentration of the ammonium sulfate in the ammonia mixed solution is increased to a certain amount, the discharge pump 7 is used to transport the ammonia mixed solution with a high concentration of ammonium sulfate to the circulating crystallizer 4 to crystallize the ammonium sulfate, and the ammonium sulfate crystals are formed.
[0031] Further, the lower part of the circulating crystallizer 4 is provided with a stirrer. The stirrer is used to increase the crystallization efficiency, and the ammonium sulfate small crystals collected from the filter inclined plate 27 are fully contacted with the mixed solution, so that the ammonium sulfate small crystals are continuously aggregated to form large crystals meeting the industrial standards.
[0032] In summary, the working principle of the ammonia flue gas desulfurization device is as follows: the tail gas formed after industrial production enters the primary filter 1, is filtered by the primary filter 1 to remove large particles, and is filtered to form primary flue gas. At this time, the temperature is high, and the primary flue gas enters the desulfurization tower body 2 and is in the concentration crystallization section 22. The primary flue gas is cooled by the first spray pipe 26 and continues to rise. At this time, the ammonia mixed solution in the oxidation section 21 is uniformly sprayed out through the multi-layer spray pipe 28 and is in countercurrent contact with the flue gas to perform a desulfurization reaction, so that the SO2 in the flue gas is completely removed. At this time, the SO2 in the flue gas is absorbed to form ammonium sulfite, the flue gas continues to rise to the demisting section 24, is distributed more uniformly through the filler layer 241, and is subjected to a large amount of water mist through the water spray pipe 242 to trap escaped ammonia, so that the ammonia is further removed and the ammonia loss is reduced. At this time, the flue gas is subjected to water removal through the demister 243, so that the water content in the flue gas is reduced, and the flue gas contains only a small amount of small particles and aerosols. At this time, the small particles and aerosols are further removed through the electric dust collector 3, so that the flue gas meets the national tail gas emission standard, and the flue gas is discharged into the atmosphere.
[0033] Meanwhile, in the process of purifying the flue gas, the ammonium sulfite formed by the flue gas flowing through the absorption section 23 flows into the oxidation section 21 to form ammonium sulfate solvent after oxidation. When the content of ammonium sulfate solvent in the ammoniated mixed solution is high, the discharge pump 7 is used to transport the mixed solution to the circulating crystallizer 4 for crystallization. When crystallization occurs in the circulating crystallizer 4, crystallization starts from the bottom, so that the upper solution in the circulating crystallizer 4 is still the ammoniated mixed solution containing dilute ammonium sulfate. This part of the solution is transported to the first spray pipe 26, so that the flue gas can be preliminarily cooled and desulfurized. Due to the cooling of hot flue gas, the ammoniated mixed solution containing dilute ammonium sulfate evaporates to form a small amount of ammonium sulfate crystals, which are collected by the filter inclined plate 27 and transported back to the circulating crystallizer 4. The small crystals are in full contact with the mixed solution, so that the small ammonium sulfate crystals can be continuously aggregated to form large crystals meeting the industrial standards. Then the solid-containing filtrate is transported to the next process to form ammonium sulfate, thereby improving the yield of ammonium sulfate. The device has high desulfurization efficiency and can purify the flue gas thoroughly at one time. It can also prevent the ammonia liquid from escaping from the desulfurization tower body 2, fully utilize the ammoniated mixed solution, improve the yield of ammonium sulfate, and reduce the production cost. The problems of incomplete flue gas purification in the prior art, easy ammonia escape, the need for repeated purification, low desulfurization efficiency, low yield of ammonium sulfate after flue gas desulfurization, and high production cost are solved.
[0034] The above is only an embodiment of the present application and does not limit the protection scope of the present application. For those skilled in the art, the present application can have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the present application shall be included in the protection scope of the present application. It should be noted that similar reference numbers and letters represent similar items in the following drawings, so once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings.
Claims
1. An ammonia-based flue gas desulfurization device, characterized in that, include: A preliminary filter (1) is fixedly connected to a desulfurization tower body (2). The desulfurization tower body (2) is divided into an oxidation section (21), a concentration and crystallization section (22), an absorption section (23), and a demisting section (24) from bottom to top. The preliminary filter (1) is fixedly connected to the concentration and crystallization section (22). An electrostatic precipitator (3) is connected to the top of the desulfurization tower body (2). A spray pipe (25) is provided between the oxidation section (21) and the absorption section (23). A circulating crystallizer (4) is fixedly connected to the concentration and crystallization section (22). The bottom end of the circulating crystallizer (4) is fixedly connected to the bottom of the oxidation section (21).
2. The ammonia-based flue gas desulfurization device according to claim 1, characterized in that, An oxygenator (5) and a liquid nitrogen pump (6) are installed at the oxidation section (21).
3. The ammonia-based flue gas desulfurization device according to claim 1, characterized in that, A first spray pipe (26) is provided at the concentration crystallization section (22), and the first spray pipe (26) is connected to the upper end of the circulating crystallizer (4).
4. The ammonia-based flue gas desulfurization device according to claim 3, characterized in that, A filter inclined plate (27) is provided at the bottom of the concentrated crystallization section (22), and the inclined end of the filter inclined plate (27) is fixedly connected to the bottom end of the circulating crystallizer (4).
5. The ammonia-based flue gas desulfurization device according to claim 4, characterized in that, A crystallization delivery pump (29) is provided at the connection pipe between the filter inclined plate (27) and the circulating crystallizer (4).
6. The ammonia-based flue gas desulfurization device according to claim 1, characterized in that, The absorption section (23) is provided with a multi-layer spray pipe (28), which is fixedly connected to the oxidation section (21).
7. The ammonia-based flue gas desulfurization device according to claim 1, characterized in that, The demisting section (24) includes a packing layer (241), a water spray pipe (242), and a demister (243). The packing layer (241) is disposed above the absorption section (23), the water spray pipe (242) is disposed above the packing layer (241), and the demister (243) is installed above the water spray pipe (242).
8. The ammonia-based flue gas desulfurization device according to claim 1, characterized in that, A discharge pump (7) is installed on the pipe connecting the bottom end of the oxidation section (21) and the bottom end of the circulating crystallizer (4).
9. The ammonia-based flue gas desulfurization device according to claim 1, characterized in that, A stirrer is provided in the lower middle part of the circulating crystallizer (4).