Device for treating ammonia gas in ammonium paratungstate calcination tail gas
Through multi-stage treatments such as cyclone dust removal, cooling, reaction deaminolysis, fluorochloroadsorption and deep purification, the problems of low ammonia recovery and impurity pollution in ammonium paratungstate calcined tail gas are solved, and efficient ammonia recovery and purification are achieved to generate ammonium phosphate salts that can be used for nitrogen fertilizers.
Patent Information
- Application Number
- CN202510893615.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-06-30
- Publication Date
- 2025-08-26
AI Technical Summary
In the prior art, the ammonium paratungstate calcined tail gas treatment equipment has problems such as low ammonia recovery rate and unseparation of fluorine-chlorochloro-impact impurities, and the direct entry of high-temperature tail gas into the washing section leads to a reduced ammonia dissolution efficiency, and dust is mixed with HF/HCl, making it difficult to meet the ammonia fertilizer standards.
The dust is separated by a cyclone dust collector, the cooling box cools down, the reaction deaming box uses a phosphoric acid solution to generate ammonium phosphate salt, the fluorochloroadsorption box removes HF and HCl, the dust removal box removes dust, the water-eluent ammonia box physically dissolves ammonia, and the deep purification box chemically absorbs residual ammonia, and achieves efficient ammonia recovery and purification through multi-stage treatment.
It has achieved efficient recycling of ammonium phosphate, improved resource utilization, ensured the purity of ammonium phosphate, met environmental protection requirements, reduced the ammonia concentration in waste gas, and generated products that can be used for nitrogen fertilizers.
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Figure CN120532285A_ABST
Abstract
Description
Technical Field
[0001] The invention relates to the technical field of waste gas or similar gas processing equipment, and in particular to a device for processing ammonia in tail gas from the calcination of ammonium paratungstate. Background Art
[0002] During the calcination process of ammonium paratungstate (APT), tail gas containing ammonia and other components will be produced. The concentration of ammonia (NH3) in the tail gas is as high as 5%-15%. It also contains WO3 dust, trace amounts of HF / HCl and water vapor.
[0003] Traditional exhaust gas treatment equipment often uses water scrubbing and absorption, but this suffers from low ammonia recovery rates and the failure to separate fluorine and chlorine impurities, leading to subsequent fertilizer contamination. Existing equipment is mostly single-stage spray towers, which are unable to effectively remove fluorine and chlorine compounds from exhaust gas. High-temperature exhaust gas (200-500°C) enters the absorption stage directly. When traditional water scrubbing and ammonia removal processes are operated above 80°C, ammonia solubility drops sharply (at 60°C, it is only 30% of that at 20°C). This results in temperature-dependent suppression of ammonia dissolution efficiency, and dust mixes with HF / HCl into the liquid phase, causing the recovered ammonium salt to contain excessive fluorine and chlorine, making it difficult to meet ammonia fertilizer standards. Summary of the Invention
[0004] To solve the above problems, the present invention proposes a device for treating ammonia in tail gas from the calcination of ammonium paratungstate, comprising a cyclone dust collector that separates dust from the tail gas using centrifugal force; a cooling box is provided on the side of the cyclone dust collector, and a cold air inlet pipe is connected to the outer wall of the cooling box. The cooling box cools the tail gas, facilitating subsequent reaction of ammonia in the tail gas at room temperature; A reaction deamination box is arranged on the side of the cooling box. The air inlet end of the reaction deamination box and the air outlet end of the cooling box are connected by a connecting pipe. The outer wall of the reaction deamination box is connected to a phosphoric acid spray pipe, which is used to spray 15%-20% phosphoric acid solution. An ammonium phosphate deposition plate is installed on the inner wall of the reaction deamination box, and air holes for exhaust gas to pass through are opened on the ammonium phosphate deposition plate.
[0005] Furthermore, a fluorine and chlorine adsorption box is provided between the cooling box and the cyclone dust collector. The output end of the cyclone dust collector is connected to the air inlet end of the fluorine and chlorine adsorption box through a connecting pipe. An adsorption bed is installed in the fluorine and chlorine adsorption box, and the adsorption bed is filled with alumina. HF and HCl in the high-temperature exhaust gas react with Al2O3 to prevent HF and HCl from intervening in the subsequent deamination process and reacting with the phosphoric acid solution, thereby affecting the purity of the recovered ammonium phosphate salt.
[0006] Furthermore, a dust removal box is provided between the fluorine and chlorine adsorption box and the cooling box. The air outlet of the fluorine and chlorine adsorption box is connected to the air inlet of the dust removal box through a connecting pipe. The air outlet of the dust removal box is connected to the air inlet of the cooling box through a connecting pipe. An atomizing spray pipe is installed on the dust removal box, and the atomizing spray pipe sprays circulating water. A dust deposition plate is installed on the inner wall of the dust removal box. The dust deposition plate is provided with air holes for the exhaust gas to pass through. The dust deposition plate collects the settled WO3 dust. Since the exhaust gas is still in a high-temperature state at this time, the solubility of ammonia in water at high temperature is extremely low, so it does not affect the subsequent deammoniation treatment, and can remove residual dust, thereby avoiding affecting the purity of the ammonium phosphate salt recovered subsequently.
[0007] Furthermore, a water washing deammoniation box is provided on the side of the reaction deammoniation box. The air inlet end of the water washing deammoniation box is connected to the air outlet end of the reaction deammoniation box by a connecting pipe. A process water spray pipe is installed on the water washing deammoniation box to physically dissolve the escaped ammonia by spraying process water and capture the phosphoric acid mist.
[0008] Furthermore, a deep purification box is provided on the side of the water washing and deammonification box. The air inlet end of the deep purification box is connected to the water washing and deammonification box through a connecting pipe. A dilute sulfuric acid spray pipe is installed on the deep purification box. The dilute sulfuric acid spray pipe sprays 0.5% dilute sulfuric acid solution to chemically absorb residual ammonia and generate ammonium sulfate solution. An activated carbon adsorption plate is also installed in the deep purification box, and a discharge pipe is installed on the deep purification box.
[0009] Furthermore, the connecting pipe is connected to an air pump, and an opening and closing valve is also installed on the connecting pipe.
[0010] Furthermore, a temperature sensor A is installed in the cooling box, a temperature sensor B and a pH meter are installed in the reaction deammoniation box, and a temperature sensor C is installed in the fluorine and chlorine adsorption box.
[0011] Furthermore, a spiral guide plate is fixed on the upper end of the inner walls of the fluorine and chlorine adsorption box, the dust removal box and the reaction deammoniation box.
[0012] Furthermore, the fluorine and chlorine adsorption box, dust removal box, reaction deammonification box and deep purification box are all equipped with maintenance windows. By opening their respective maintenance windows, the adsorption bed, dust deposition plate, ammonium phosphate deposition plate and activated carbon adsorption plate can be taken out for cleaning, maintenance and replacement; the outer walls of the fluorine and chlorine adsorption box, dust removal box, reaction deammonification box, water washing deammonification box and deep purification box are all equipped with drainage pipes.
[0013] Furthermore, the reaction tube, fluorine and chlorine adsorption box, dust removal box, cooling box, reaction deammonification box, water washing deammonification box and deep purification box are all made of fiberglass, and the inner walls of the fluorine and chlorine adsorption box, reaction deammonification box and deep purification box are fixed with corrosion-resistant PP / PTFE lining.
[0014] The beneficial effects of the present invention are as follows: 1. By setting up a reaction deammonification box and using phosphoric acid solution to react with ammonia to generate ammonium phosphate, efficient recovery of ammonia in tail gas is achieved. The recovered ammonium phosphate can be further processed to make nitrogen fertilizer, which improves resource utilization and reduces ammonia emissions.
[0015] 2. During the tail gas treatment process, a fluorine and chlorine adsorption box is installed to effectively remove fluorine and chlorine impurities in the tail gas, preventing them from reacting with the phosphoric acid solution during the subsequent deamination process to form impure salts, thereby ensuring the purity of the recovered ammonium phosphate. At the same time, the installation of a dust removal box and cyclone dust collector further removes dust from the tail gas, preventing dust from affecting the purity of the subsequently recovered ammonium phosphate.
[0016] 3. The installation of a water-washing ammonia removal tank and a deep purification tank provides deep purification of the exhaust gas. The water-washing ammonia removal tank physically dissolves escaped ammonia, further reducing the ammonia concentration in the exhaust gas and capturing phosphoric acid mist. The deep purification tank uses dilute sulfuric acid to chemically absorb residual ammonia, generating an ammonium sulfate solution. Simultaneously, activated carbon adsorption plates absorb other residual impurities, ensuring that the exhaust gas meets emission standards and environmental requirements. BRIEF DESCRIPTION OF THE DRAWINGS
[0017] Figure 1 This is a schematic structural diagram of Example 1 of the present invention; Figure 2 This is a schematic structural diagram of Example 2 of the present invention; Figure 3 This is a schematic structural diagram of the fluorine and chlorine adsorption box and the dust removal box in the present invention; Figure 4 It is a structural schematic diagram of the cooling box and the reaction deamination box in the present invention; Figure 5 It is a structural schematic diagram of the water washing and deammonification box and the deep purification box in the present invention.
[0018] The accompanying drawings are marked as follows: 1. Cyclone dust collector; 2. Fluorine and chlorine adsorption box; 201. Adsorption bed; 202. Temperature sensor C; 3. Dust removal box; 301. Atomizing spray pipe; 302. Dust deposition plate; 4. Cooling box; 401. Cold air inlet pipe; 402. Temperature sensor A; 5. Reaction deamination box; 501. Phosphoric acid spray pipe; 502. Ammonium phosphate deposition plate; 503. Temperature sensor B; 504. pH meter; 6. Water washing deamination box; 601. Process water spray pipe; 7. Deep purification box; 701. Dilute sulfuric acid spray pipe; 702. Activated carbon adsorption plate; 8. Connecting pipe; 9. Air pump; 10. On-off valve; 11. Spiral guide plate; 12. Discharge pipe. DETAILED DESCRIPTION
[0019] In the description of the present invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings and are intended solely to facilitate and simplify the description of the present invention. They are not intended to indicate or imply that the devices or components referred to must have a specific orientation, be constructed, or operate in a specific orientation. Therefore, they should not be construed as limitations on the present invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.
[0020] In the description of the present invention, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood in a broad sense. For example, they may refer to fixed, detachable, or integral connections; mechanical or electrical connections; direct or indirect connections through an intermediate medium; and internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on the specific circumstances.
[0021] The present invention will be further described below with reference to the accompanying drawings: Example 1 A device for treating ammonia in tail gas from the calcination of ammonium paratungstate, such as Figure 1 and Figure 2 As shown, the cyclone dust collector 1 is included. The tail gas of ammonium paratungstate calcination first enters the cyclone dust collector 1. Inside the cyclone dust collector 1, under the action of centrifugal force, the dust particles of the tail gas are thrown to the wall of the device and settle along the wall, thereby achieving the initial separation of dust in the tail gas.
[0022] like Figure 1 and Figure 3 As shown, in this embodiment, a pre-treatment link for ammonia removal is provided, a fluorine and chlorine adsorption box 2 is provided on the side of the cyclone dust collector 1, the output end of the cyclone dust collector 1 is connected to the air inlet end of the fluorine and chlorine adsorption box 2 through a connecting pipe 8, an adsorption bed 201 is installed in the fluorine and chlorine adsorption box 2, and the adsorption bed 201 is filled with alumina. HF and HCl in the high-temperature exhaust gas react with Al2O3 to prevent HF and HCl from intervening in the subsequent deammoniation process and reacting with the phosphoric acid solution, thereby affecting the purity of the recovered ammonium phosphate salt. A temperature sensor C202 is installed in the fluorine and chlorine adsorption box 2, and a spiral guide plate 11 is fixed to the upper end of the inner wall of the fluorine and chlorine adsorption box 2.
[0023] The reaction formula in the fluorine and chlorine adsorption box 2 is: 2HF+Al2O3→2AlF3↓+H2O 2HCl+Al2O3→2AlCl3↓+H2O Fluorine and chlorine impurities in the tail gas are removed when the tail gas is still at a high temperature (100-200°C) to prevent contamination of ammonium phosphate fertilizer. The reaction conditions between alumina and ammonia are more stringent, generally occurring above 400°C-500°C, and usually require a sufficiently long time to achieve complete conversion. Therefore, this process will not affect the subsequent recovery of ammonia.
[0024] In this embodiment, a dust removal box 3 is provided on the side of the fluorine and chlorine adsorption box 2. The air outlet end of the fluorine and chlorine adsorption box 2 is connected to the air inlet end of the dust removal box 3 through a connecting pipe 8. The air outlet end of the dust removal box 3 is connected to the air inlet end of the cooling box 4 through a connecting pipe 8. An atomizing spray pipe 301 is installed on the dust removal box 3. The atomizing spray pipe 301 sprays circulating water. A dust deposition plate 302 is installed on the inner wall of the dust removal box 3. The dust deposition plate 302 is provided with air holes for exhaust gas to pass through. A spiral guide plate 11 is fixed to the upper end of the inner wall of the dust removal box 3.
[0025] The dust deposition plate 302 collects the settled WO3 dust. Since the tail gas is still in a high temperature state at this time, the solubility of ammonia in water at high temperature is extremely low, so it does not affect the subsequent deammoniation treatment, and can remove residual dust to avoid affecting the purity of the subsequently recovered ammonium phosphate salt.
[0026] like Figure 1 and Figure 4 As shown, in this embodiment, a cooling box 4 is provided on the side of the dust removal box 3, and a cold air inlet pipe 401 is connected to the outer wall of the cooling box 4. The cooling box 4 cools the exhaust gas to facilitate the subsequent reaction of ammonia in the exhaust gas at room temperature; a reaction deamination box 5 is provided on the side of the cooling box 4, and the air inlet end of the reaction deamination box 5 and the air outlet end of the cooling box 4 are connected by a connecting pipe 8. The outer wall of the reaction deamination box 5 is connected to a phosphoric acid spray pipe 501, and the phosphoric acid spray pipe 501 is used to spray 15%-20% phosphoric acid solution. An ammonium phosphate deposition plate 502 is installed on the inner wall of the reaction deamination box 5, and an air hole for the exhaust gas to pass through is opened on the ammonium phosphate deposition plate 502; a temperature sensor A402 is installed in the cooling box 4, a temperature sensor B503 and a pH meter 504 are installed in the reaction deamination box 5, and a spiral guide plate 11 is fixed to the upper end of the inner wall of the reaction deamination box 5.
[0027] The cold air inlet pipe 401 inputs cold air into the cooling box 4 to cool the exhaust gas. The temperature sensor A402 monitors the exhaust gas temperature and reduces the exhaust gas temperature to room temperature to facilitate the subsequent reaction of ammonia and phosphoric acid solution.
[0028] The reaction formula in the reaction deamination box 5 is: NH3+H3PO4→NH4H2PO4 (ammonium dihydrogen phosphate) NH3+NH4H2PO4→(NH4)2HPO4 (diammonium hydrogen phosphate) In order to achieve efficient recovery of ammonia, ammonium phosphate slurry (containing N10~12%, P2O548~52%) is produced. The recovered ammonium phosphate salt can be separated by temperature-controlled crystallization and used to make nitrogen fertilizer.
[0029] Example 2 On the basis of the above embodiment 1, Figure 2 and Figure 5 As shown, a water washing deammoniation box 6 is further provided on the side of the reaction deammoniation box 5. The air inlet end of the water washing deammoniation box 6 is connected to the air outlet end of the reaction deammoniation box 5 through a connecting pipe 8. A process water spray pipe 601 is installed on the water washing deammoniation box 6.
[0030] The reaction formula in the water washing and deammonification box 6 is: NH3+H2O⇌NH4OH By spraying process water to physically dissolve the escaped ammonia, the recovered ammonia water can be reused in the APT crystallization section to further reduce the ammonia concentration in the exhaust gas and capture phosphoric acid mist.
[0031] In this embodiment, a deep purification box 7 is provided on the side of the water washing and deammonification box 6. The air inlet end of the deep purification box 7 is connected to the water washing and deammonification box 6 through a connecting pipe 8. A dilute sulfuric acid spray pipe 701 is installed on the deep purification box 7. The dilute sulfuric acid spray pipe 701 sprays 0.5% dilute sulfuric acid solution. An activated carbon adsorption plate 702 is also installed in the deep purification box 7 to adsorb other residual impurities. A discharge pipe 12 is installed on the deep purification box 7.
[0032] The reaction formula in the deep purification box 7 is: 2NH3+H2SO4→(NH4)2SO4 The residual ammonia is chemically absorbed to generate ammonium sulfate solution, which can be evaporated to make fertilizer.
[0033] like Figure 1 and Figure 2 As shown, in this embodiment, the connecting pipe 8 is connected to the air pump 9, and the connecting pipe 8 is also equipped with an opening and closing valve 10; the fluorine and chlorine adsorption box 2, the dust removal box 3, the reaction deamination box 5 and the deep purification box 7 are all opened and closed with maintenance windows, and the adsorption bed 201, the dust deposition plate 302, the ammonium phosphate deposition plate 502 and the activated carbon adsorption plate 702 can be taken out by opening their respective maintenance windows for easy cleaning, maintenance and replacement; the outer walls of the fluorine and chlorine adsorption box 2, the dust removal box 3, the reaction deamination box 5, the water washing deamination box 6 and the deep purification box 7 are all equipped with drain pipes; the reaction tube, the fluorine and chlorine adsorption box 2, the dust removal box 3, the cooling box 4, the reaction deamination box 5, the water washing deamination box 6 and the deep purification box 7 are all made of glass fiber reinforced plastics, and the inner walls of the fluorine and chlorine adsorption box 2, the reaction deamination box 5 and the deep purification box 7 are fixed with corrosion-resistant PP / PTFE linings.
[0034] It is further explained that, for the recovered liquid in the reaction deammonification box 5, since there is chloride that may partially escape, ammonium phosphate post-treatment can be performed. By utilizing the difference in solubility between ammonium phosphate and ammonium chloride (solubility at 25°C: NH4Cl29.4g / 100g water, NH4H2PO411g / 100g water), temperature-controlled crystallization separation is performed, and water washing-recrystallization is performed. The reaction formula is as follows: NH4Cl(s)+H2O→NH4⁺(aq)+Cl⁻(aq) (highly soluble) NH4H2PO4(s)+H2O→NH4H2PO4(aq) (low solubility) To reduce the heavy chloride content of ammonia fertilizer and purify ammonium phosphate to meet GB / T10205 standards.
[0035] The basic principles, main features, and advantages of the present invention are shown and described above. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The above embodiments and descriptions are merely illustrative of the principles of the present invention. Various changes and modifications may be made to the present invention without departing from the spirit and scope of the present invention, and such changes and modifications fall within the scope of the invention as claimed.
Claims
1. A device for treating ammonia in tail gas from the calcination of ammonium paratungstate, comprising a cyclone dust collector (1) for separating dust in the tail gas by centrifugal force; characterized in that: A cooling box (4) is provided on the side of the cyclone dust collector (1), and a cold air inlet pipe (401) is connected to the outer wall of the cooling box (4). The cooling box (4) cools the tail gas to facilitate subsequent reaction of ammonia in the tail gas at room temperature. A reaction deamination box (5) is provided on the side of the cooling box (4). The air inlet of the reaction deamination box (5) and the air outlet of the cooling box (4) are connected via a connecting pipe (8). A phosphoric acid spray pipe (501) is connected to the outer wall of the reaction deamination box (5). The phosphoric acid spray pipe (501) is used to spray a 15%-20% phosphoric acid solution. An ammonium phosphate deposition plate (502) is installed on the inner wall of the reaction deamination box (5). The ammonium phosphate deposition plate (502) is provided with air holes for the exhaust gas to pass through.
2. The device for treating ammonia in tail gas from calcination of ammonium paratungstate according to claim 1, wherein: A fluorine and chlorine adsorption box (2) is provided between the cooling box (4) and the cyclone dust collector (1). The output end of the cyclone dust collector (1) is connected to the air inlet end of the fluorine and chlorine adsorption box (2) via a connecting pipe (8). An adsorption bed (201) is installed in the fluorine and chlorine adsorption box (2). The adsorption bed (201) is filled with aluminum oxide. HF and HCl in the high-temperature exhaust gas react with Al2O3 to prevent HF and HCl from intervening in the subsequent deamination process and reacting with the phosphoric acid solution, thereby affecting the purity of the recovered ammonium phosphate salt.
3. The device for treating ammonia in tail gas from calcination of ammonium paratungstate according to claim 2, wherein: A dust removal box (3) is provided between the fluorine and chlorine adsorption box (2) and the cooling box (4). The air outlet of the fluorine and chlorine adsorption box (2) is connected to the air inlet of the dust removal box (3) through a connecting pipe (8). The air outlet of the dust removal box (3) is connected to the air inlet of the cooling box (4) through a connecting pipe (8). An atomizing spray pipe (301) is installed on the dust removal box (3). The atomizing spray pipe (301) sprays circulating water. A dust deposition plate (302) is installed on the inner wall of the dust removal box (3). The dust deposition plate (302) is provided with air holes for the exhaust gas to pass through. The dust deposition plate (302) collects the settled WO3 dust. Since the exhaust gas is still in a high-temperature state at this time, the solubility of ammonia in water at high temperature is extremely low, so it does not affect the subsequent deammoniation treatment, and the residual dust can be removed, thereby avoiding affecting the purity of the ammonium phosphate salt recovered subsequently.
4. The device for treating ammonia in tail gas from the calcination of ammonium paratungstate according to claim 3, wherein: A water washing deammoniation box (6) is further provided on the side of the reaction deammoniation box (5). The air inlet of the water washing deammoniation box (6) is connected to the air outlet of the reaction deammoniation box (5) via a connecting pipe (8). A process water spray pipe (601) is installed on the water washing deammoniation box (6) to physically dissolve the escaped ammonia by spraying process water and to capture phosphoric acid mist.
5. The device for treating ammonia in tail gas from the calcination of ammonium paratungstate according to claim 4, characterized in that: A deep purification box (7) is provided on the side of the water washing and deammonification box (6). The air inlet end of the deep purification box (7) is connected to the water washing and deammonification box (6) via a connecting pipe (8). A dilute sulfuric acid spray pipe (701) is installed on the deep purification box (7). The dilute sulfuric acid spray pipe (701) sprays 0.5% dilute sulfuric acid solution to chemically absorb residual ammonia and generate ammonium sulfate solution. An activated carbon adsorption plate (702) is also installed in the deep purification box (7). A discharge pipe (12) is installed on the deep purification box (7).
6. The device for treating ammonia in tail gas from calcination of ammonium paratungstate according to any one of claims 1 to 5, characterized in that: The connecting pipe (8) is connected to an air pump (9), and an opening and closing valve (10) is also installed on the connecting pipe (8).
7. The device for treating ammonia in tail gas from the calcination of ammonium paratungstate according to claim 3, characterized in that: A temperature sensor A (402) is installed in the cooling box (4), a temperature sensor B (503) and a pH meter (504) are installed in the reaction deammoniation box (5), and a temperature sensor C (202) is installed in the fluorine and chlorine adsorption box (2).
8. The device for treating ammonia in tail gas from the calcination of ammonium paratungstate according to claim 2, wherein: A spiral guide plate (11) is fixed to the upper end of the inner wall of the fluorine and chlorine adsorption box (2), the dust removal box (3) and the reaction deammoniation box (5).
9. The device for treating ammonia in tail gas from the calcination of ammonium paratungstate according to claim 5, characterized in that: The fluorine and chlorine adsorption box (2), the dust removal box (3), the reaction deammoniation box (5) and the deep purification box (7) are all provided with maintenance windows. By opening the respective maintenance windows, the adsorption bed (201), the dust deposition plate (302), the ammonium phosphate deposition plate (502) and the activated carbon adsorption plate (702) can be taken out for easy cleaning, maintenance and replacement. The outer walls of the fluorine and chlorine adsorption box (2), the dust removal box (3), the reaction deammoniation box (5), the water washing deammoniation box (6) and the deep purification box (7) are all provided with drainage pipes.
10. The device for treating ammonia in tail gas from the calcination of ammonium paratungstate according to claim 5, characterized in that: The reaction tube, the fluorine and chlorine adsorption box (2), the dust removal box (3), the cooling box (4), the reaction deammoniation box (5), the water washing deammoniation box (6) and the deep purification box (7) are all made of glass fiber reinforced plastics. The inner walls of the fluorine and chlorine adsorption box (2), the reaction deammoniation box (5) and the deep purification box (7) are fixed with corrosion-resistant PP / PTFE linings.