Device and method for emptying waste liquid concentrated ammonia absorption tower

Abstract

The invention discloses a waste liquid concentrated ammonia absorption tower emptying device and method, and relates to the technical field of waste gas treatment. The device comprises an ammonia gas absorption tower, an alkali recovery furnace, a denitration tower and a desulfurization tower which are sequentially connected, the ammonia gas absorption tower is communicated with the alkali recovery furnace through a discharge pipe; a condensate storage tank communicated with the second-effect evaporation chamber is communicated with the discharge pipe; the ammonia absorption tower is respectively communicated with the first-effect evaporation chamber and the second-effect evaporation chamber; and an ammonia gas absorption filler is arranged in the ammonia gas absorption tower. The waste gas treatment device can perform multi-stage purification treatment on waste gas, effectively remove particulate matters, nitrogen oxides and sulfur dioxide in the waste gas, ensure that the discharged gas meets the environmental protection standard, and reduce the pollution to the environment; and the ammonia-containing waste gas is treated by the alkali recovery furnace, so that the alkali is recycled.

Description

Technical Field

[0001] The present invention relates to the technical field of waste gas treatment, and in particular to a waste liquid concentrated ammonia absorption tower venting device and method. Background Art

[0002] Disclosing the information of this background art section is only intended to increase the understanding of the overall background of the present invention, and it is not necessarily regarded as an admission or an implication in any form that this information constitutes the prior art already known to those of ordinary skill in the art.

[0003] The caprolactam workshop includes a first-effect evaporation chamber and a second-effect evaporation chamber connected in series. The secondary steam of the first-effect evaporation chamber is the heating source of the second-effect evaporation chamber. The material flows from the first effect to the second effect in the caprolactam workshop. The original design of the waste liquid concentration device in the caprolactam workshop is to first carry out an alkali addition reaction on the refined waste liquid. The ammonia gas generated by the alkali addition reaction and the non-condensable gas in the second-effect evaporation chamber enter the ammonia absorption tower for absorption and then are discharged into the atmosphere. The process condensate generated by the second-effect evaporation chamber enters the condensate storage tank and is sent to the biochemical post. After later optimization and adjustment, the refined waste liquid directly enters the second-effect evaporation chamber for concentration without alkali addition. The non-condensable gas in the second-effect evaporation chamber enters the ammonia absorption tower and is then discharged into the atmosphere. During actual operation, it is detected that the VOC in the venting of the ammonia absorption tower and the venting of the process condensate storage tank exceeds the standard, and the surrounding odor is obvious. The main reasons are as follows: 1. Deviation of the core design goal: After canceling the alkali decomposition step, the organic nitrogen-containing compounds (such as caprolactam monomers, oligomers, cyclohexanone oxime, etc.) and possible other organic solvent residues in the waste liquid are not decomposed into ammonia, but directly enter the evaporation system. These organic compounds have relatively high boiling points and will partially escape in the form of gas with the secondary steam and non-condensable gas during the evaporation and concentration process, becoming the main source of VOC.

[0004] 2. Underestimation / neglect of the complexity of waste gas components: Currently, it is considered that the main pollutant is ammonia (solved by the absorption tower). Since the designed temperature of the second-effect evaporation chamber is lower than that of the first-effect evaporation chamber, it is expected that the volatilization amount of organic compounds is limited, and the concentration of organic compounds dissolved in the process condensate (condensed water) should be very low. The volatility of the undecomposed organic compounds under high vacuum and heating conditions (even if the temperature is not high) is ignored, as well as their distribution in the gas phase (non-condensable gas) and liquid phase (condensate). These organic compounds are the main contributors to VOC and odor.

[0005] Therefore, designing an exhaust gas treatment device and method adapted to the caprolactam production process after canceling the alkali decomposition step is an urgent problem to be solved by those skilled in the art. Summary of the Invention

[0006] Aiming at the deficiencies of the existing technology, the purpose of the present invention is to provide a waste liquid concentrated ammonia absorption tower venting device and method, which use devices such as a dust collector, a denitration tower, and a desulfurization tower to perform multi-stage purification treatment on the waste gas.

[0007] To achieve the above object, the present invention is realized by the following technical solutions: In a first aspect of the present invention, a waste liquid concentrated ammonia absorption tower venting device is provided, which includes an ammonia absorption tower, an alkali recovery furnace, a denitration tower, and a desulfurization tower connected in sequence; a discharge pipe communicates between the ammonia absorption tower and the alkali recovery furnace; a condensate storage tank communicating with the second effect evaporation chamber communicates with the discharge pipe; the ammonia absorption tower communicates with the first effect evaporation chamber and the second effect evaporation chamber respectively; ammonia absorption packing is arranged in the ammonia absorption tower.

[0008] Optionally, an ammonia absorption packing replacement device is arranged outside the ammonia absorption tower. The packing replacement device includes a vertically arranged vertical telescopic rod, a rotatable block driven by the vertical telescopic rod is arranged on the vertical telescopic rod, two first telescopic rods are symmetrically arranged on the rotatable block, and a second telescopic rod facing the ammonia absorption tower is connected to the end of the first telescopic rod; a clamping plate is arranged at the end of the second telescopic rod. A feed inlet is arranged on the side wall of the ammonia absorption tower, and vertically penetrating limiting rings are arranged on both sides of the feed inlet; a sealing door capable of opening outward is arranged on the feed inlet; inside the ammonia absorption tower, a limiting cylinder is fixed on the sealing door, a reduced diameter structure is arranged in the middle of the limiting cylinder in the height direction, and the ammonia absorption packing is placed above the reduced diameter structure; second sliders capable of sliding up and down are arranged on both sides of the sealing door, and upper and lower symmetric C-shaped structures formed by bending outward and further bending relatively are arranged at the upper and lower ends of the second sliders respectively, and the notch of the C-shaped structure is close to the side wall of the ammonia absorption tower. The end of the C-shaped structure is inserted into the limiting ring.

[0009] In a second aspect, a waste liquid concentrated ammonia treatment method based on the above waste liquid concentrated ammonia absorption tower venting device includes the following processes: The non-condensable gases in the first effect evaporation chamber and the second effect evaporation chamber enter the ammonia absorption tower, and the ammonia components in the non-condensable gases are absorbed; the volatile gases in the condensate storage tank and the gases discharged from the ammonia absorption tower are mixed in the discharge pipe and then discharged to the atmosphere after being treated by the alkali recovery furnace, the denitration tower, and the desulfurization tower.

[0010] The beneficial effects of the present invention are as follows: 1. The device provided by the present invention includes a dust removal filter cartridge, a denitration tower, and a desulfurization tower, which can perform multi-stage purification treatment on waste gas, effectively remove particulate matter, nitrogen oxides, and sulfur dioxide in the waste gas, ensure that the discharged gas meets environmental protection standards, and reduce environmental pollution; by treating ammonia-containing waste gas with an alkali recovery furnace, the recovery and utilization of alkali are realized, the production cost is reduced, and at the same time, the emission of waste is reduced, meeting the requirements of circular economy.

[0011] 2. Multiple control valves are provided in the venting device of the present invention, such as the second control valve, the third control valve, the fifth control valve, etc., which can automatically adjust the gas discharge path according to the waste gas detection results to ensure that the waste gas is discharged after meeting the standards and avoid the impact on the environment caused by excessive emissions.

[0012] 3. The device of the present invention includes an ammonia absorption packing replacement device, which realizes automatic operation in the process of replacing the packing body, reduces manual intervention, and significantly improves the operation efficiency. In particular, the ammonia absorption packing is installed inside the sealing door, so that the process of opening the sealing door and the process of replacing the ammonia absorption packing are continuous, and the old ammonia absorption packing automatically falls by using the inertia principle, reducing the mechanical wear and the risk of misoperation in manual operation, extending the service life of the ammonia absorption tower and its related components. The automatic packing body replacement system can quickly complete the replacement of the packing body, reduce the downtime of the equipment, improve the production efficiency, and at the same time, the automatic operation reduces the risk of direct contact between the operator and ammonia and mechanical components, improves the safety of the operator, and reduces the probability of work-related accidents. The use of automatic equipment reduces the workload of manual handling and adjusting the packing body, reduces the labor intensity of the operator, and improves the work safety. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] The accompanying drawings forming a part of the present invention are used to provide a further understanding of the present invention. The schematic embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention.

[0014] The distances or dimensions between each part are exaggerated in the drawings for showing the positions of each part, and the schematic drawings are only for illustration.

[0015] Figure 1 It is a schematic structural diagram of a waste liquid concentrating ammonia absorption tower venting device of the present invention.

[0016] Figure 2 It is a schematic structural diagram of the ammonia absorption tower of the present invention; Figure 3 It is a schematic internal structural diagram of the ammonia absorption tower of the present invention; Figure 4 It is Figure 2 the enlarged structural diagram at A in Figure 5 It is Figure 2 the enlarged structural diagram at B in In the figure: 1. Condensate storage tank; 2. Ammonia absorption tower; 4. Alkali recovery furnace; 5. First blower device; 6. Dust removal filter cartridge; 7. Denitration tower; 8. Desulfurization tower; 9. Second blower device; 11. Overflow pipe; 12. Blind pipe; 13. First input pipe; 14. First control valve; 16. Sixth control valve; 17. Liquid inlet pipe; 21. Ammonia absorption packing; 22. First connecting pipe; 23. Second connecting pipe; 24. Chimney; 25. Second control valve; 26. Ammonia water tank; 27. Second intake pipe; 28. Third control valve; 29. Discharge pipe; 51. Fifth control valve; 81. Drain pipe; 211. Circulation pump; 202. Feed inlet; 203. Sealing door; 204. Limiting cylinder; 205. Reduced diameter structure; 206. Support rod; 208. Vertical telescopic rod; 209. First slider; 2010. Cylinder; 2012. First motor; 2013. Rotating block; 2014. First telescopic rod; 2015. Second telescopic rod; 2017. Clamp; 2018. Engaging groove; 2019. Bushing; 2020. Second slider; 2021. Connecting rod; 2022. Insert rod; 2023. Limiting ring; 2024. Engaging block. Detailed implementation mode

[0017] In the description of the present invention, it should be understood that the orientation or positional relationship indicated by the terms "center", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "axial", "radial", "circumferential", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present invention.

[0018] In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance or implicitly indicating the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the present invention, the meaning of "plurality" is two or more, unless otherwise specifically defined.

[0019] In the present invention, unless otherwise clearly specified and defined, the terms "installation", "connection", "connection", "fixation", etc. should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or integrated; it may be a mechanical connection, an electrical connection, or a communication connection; it may be directly connected, or indirectly connected through an intermediate medium, and may be the connection inside two elements or the interaction relationship between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0020] In the present invention, unless otherwise clearly specified and defined, the first feature being "on" or "under" the second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium.

[0021] One or more embodiments of the present invention provide a waste liquid concentrated ammonia absorption tower venting device, including an ammonia absorption tower, an alkali recovery furnace, a denitration tower, and a desulfurization tower connected in sequence; a discharge pipe communicates between the ammonia absorption tower and the alkali recovery furnace; a condensate storage tank communicating with the second effect evaporation chamber communicates with the discharge pipe; the ammonia absorption tower communicates with the first effect evaporation chamber and the second effect evaporation chamber respectively; An ammonia absorption filler is provided in the ammonia absorption tower.

[0022] Through the above settings, the ammonia-containing gas discharged from the first effect evaporation chamber and the ammonia-containing gas released from the condensate, and the ammonia-containing gas released from the condensate pass through the alkali recovery furnace, the denitration tower, and the desulfurization tower and are discharged. The added treatment device can effectively perform multi-stage purification treatment on the waste gas, avoiding problems such as exceeding the VOC standard and obvious surrounding odor.

[0023] Optionally, the discharge pipe communicates with an ammonia water tank.

[0024] Optionally, a dust collector is provided between the alkali recovery furnace and the denitration tower, which can effectively remove particulate matter in the waste gas.

[0025] Optionally, a first air blowing device is provided on the discharge pipe; a second air blowing device is provided between the denitration tower and the desulfurization tower.

[0026] Optionally, the condensate storage tank communicates with a first input pipe, and the first input pipe is used to input nitrogen; to keep the air pressure inside the condensate storage tank continuously greater than the outside, preventing the oxygen-containing gas in the pipeline from pouring into the condensate storage tank and causing an explosion risk.

[0027] Optionally, an opening leading to the atmosphere is provided on the discharge pipe, which is used to directly discharge when the gas in the discharge pipe meets the standard, and no longer passes through the treatment of the alkali recovery furnace, the denitration tower, and the desulfurization tower, so as to save resources.

[0028] Optionally, an ammonia absorption filler is provided in the ammonia absorption tower, and the cavity above the ammonia absorption filler and the cavity below the ammonia absorption filler in the ammonia absorption tower are connected by a circulation pump outside the ammonia absorption tower; it is used to make the treated gas pass through the ammonia absorption filler for treatment multiple times to improve the absorption effect.

[0029] Optionally, an ammonia absorption packing replacement device is provided outside the ammonia absorption tower. The packing replacement device includes a vertically arranged vertical telescopic rod. The vertical telescopic rod is provided with a driven rotating block. Two first telescopic rods are symmetrically arranged on the rotating block. The end of the first telescopic rod is connected to a second telescopic rod facing the ammonia absorption tower. A clamping plate is arranged at the end of the second telescopic rod. A feed port is provided on the side wall of the ammonia absorption tower. Vertical through limiting rings are provided on both sides of the feed port. A sealing door that can be opened outward is provided on the feed port. Inside the ammonia absorption tower, a limiting cylinder is fixed on the sealing door. A reduced-diameter structure is arranged in the middle of the limiting cylinder in the height direction. The ammonia absorption packing is placed above the reduced-diameter structure. Second sliders that can slide up and down are provided on both sides of the sealing door. C-shaped structures that are symmetric up and down and are bent toward the limiting ring and further bent relatively are arranged at the upper and lower ends of the second slider respectively. The notch of the C-shaped structure is close to the side wall of the ammonia absorption tower. The end of the C-shaped structure is inserted into the limiting ring.

[0030] Through the above settings, the automatic replacement of the ammonia absorption packing is realized: Since the ammonia absorption packing is loaded on the limiting cylinder of the sealing door, the old ammonia absorption packing can be removed from the ammonia absorption tower while the sealing door is opened. Since the second sliders provided on the sealing door are C-shaped structures that are symmetric up and down, the sealing door after being turned over up and down can still be installed back in place. Therefore, the replacement of the old and new ammonia absorption packings can be achieved through one flip.

[0031] Optionally, a support rod extending in the direction of the vertical telescopic rod is provided below the feed port to adjust the relative height of the first telescopic rod, the second telescopic rod, and the clamping plate relative to the sealing door for accurate positioning.

[0032] Optionally, a clamping groove is provided on the clamping plate, and a clamping block that engages with the shape of the clamping groove is provided on the outside of the C-shaped structure, so that the clamping plate can clamp the C-shaped structure to realize the operation of the second slider.

[0033] Optionally, the second slider is installed on a bushing of the sealing door, and the bushing is arranged at the center of the sealing door in the height direction.

[0034] Optionally, the method for replacing the ammonia absorption packing through the above device includes the steps of: controlling the height of the clamping plate by the vertical telescopic rod to be the same as that of the second slider, moving the first telescopic rod and the second telescopic rod to clamp the second slider; then lifting the vertical telescopic rod to disengage the limiting ring from the C-shaped structure; shortening the second telescopic rod to withdraw the sealing door; installing a new ammonia absorption packing under the limiting cylinder; using the rotating block to rotate the sealing door 180° up and down, turning the old ammonia absorption packing to the lower side and falling off, and turning the new ammonia absorption packing to the upper side; extending the second telescopic rod to insert the sealing door into the ammonia absorption tower, and the limiting ring enters the notch of the C-shaped structure; then lowering the vertical telescopic rod, after the upper end of the C-shaped structure is inserted into the limiting ring, extending the first telescopic rod to separate the clamping plate and the second slider, completing the replacement of the ammonia absorption packing.

[0035] One or more embodiments of the present invention provide a waste liquid concentrated ammonia treatment method based on the above-mentioned waste liquid concentrated ammonia absorption tower venting device, including the following processes: The non-condensable gases in the first-effect evaporation chamber and the second-effect evaporation chamber enter the ammonia absorption tower, and the ammonia components in the non-condensable gases are absorbed; the volatile gases in the condensate storage tank are mixed with the gases discharged from the ammonia absorption tower in the discharge pipe and then discharged to the atmosphere after passing through the alkali recovery furnace, denitration tower and desulfurization tower.

[0036] Optionally, if the ammonia concentration is up to standard after the gases discharged from the ammonia absorption tower are mixed with the volatile gases in the condensate storage tank, it is directly discharged from the opening of the discharge pipe; to simplify the treatment process, when the ammonia absorption packing needs to be replaced or the ammonia concentration is not up to standard due to unstable process, it is no longer discharged from the opening of the discharge pipe, but goes through the complete treatment process.

[0037] Optionally, nitrogen is conveyed into the condensate storage tank through the first conveying pipe to increase the internal air pressure of the condensate storage tank to be greater than the air pressure in the discharge pipe, avoiding the explosion risk.

[0038] Optionally, inside the ammonia absorption tower, the gas above the absorption packing is introduced below the absorption packing through a circulating pump outside the ammonia absorption tower for circulating treatment.

[0039] Example 1 The ammonia concentration at the outlet of the alkali recovery furnace 4 is <50 ppm. A waste liquid concentrated ammonia absorption tower venting device includes an ammonia absorption tower 2, an alkali recovery furnace 4, a denitration tower 7 and a desulfurization tower 8 connected in sequence; the ammonia absorption tower 2 and the alkali recovery furnace 4 are connected through a discharge pipe 29; the blind pipe 12 at the upper end of the condensate storage tank 1 is connected to the discharge pipe 29; the ammonia absorption tower 2 is connected to the first-effect evaporation chamber through a first connecting pipe 22 and connected to the second-effect evaporation chamber through a second connecting pipe 23.

[0040] The condensate storage tank 1 is connected to the second-effect evaporation chamber through the liquid inlet pipe 17 and is used to collect the condensate discharged from the second-effect evaporation chamber. The condensate storage tank 1 is also provided with an overflow pipe 11 for discharging excess liquid.

[0041] The discharge pipe 29 is connected to the ammonia water tank 26, which is set in the caprolactam workshop and used to store ammonia water. The ammonia water here is a key raw material for caprolactam production. A small amount of ammonia gas volatilized from the ammonia water tank 26 and the residual ammonia gas after being absorbed by the ammonia gas absorption tower 2 need to be processed subsequently. Therefore, centralized treatment is carried out here.

[0042] A dust collector is arranged between the alkali recovery furnace 4 and the denitration tower 7. The dust collector in this embodiment is selected as the dust removal filter cartridge 6.

[0043] A first air blowing device 5 is arranged on the discharge pipe 29, and a second air blowing device 9 is arranged between the denitration tower 7 and the desulfurization tower 8. Both the first air blowing device 5 and the second air blowing device 9 are used to provide gas transmission power, overcome the resistance of subsequent equipment, and ensure the smooth passage of waste gas through the treatment system.

[0044] A blind pipe 12 is arranged at the upper end of the condensate storage tank 1. The blind pipe 12 is connected to the first input pipe 13, and the first input pipe 13 is used to input nitrogen; the blind pipe 12 is connected to the discharge pipe 29 through the tenth connecting pipe and is used to discharge the volatile gas in the condensate storage tank 1 to the discharge pipe 29. Control valves are respectively arranged on the first input pipe 13 and the tenth connecting pipe.

[0045] An opening leading to the atmosphere is arranged on the discharge pipe 29 for directly discharging when the gas in the discharge pipe 29 meets the standard; a second control valve 25 is arranged on the opening. When the gas in the discharge pipe 29 does not meet the standard, the second control valve 25 is closed, and the gas in the discharge pipe 29 is processed through devices such as the alkali recovery furnace 4 and finally discharged into the atmosphere through the exhaust pipe 81.

[0046] Ammonia gas absorption packing 21 is arranged in the ammonia gas absorption tower 2. The cavity above the ammonia gas absorption packing 21 and the cavity below the ammonia gas absorption packing 21 in the ammonia gas absorption tower 2 are connected through a circulating pump 211 outside the ammonia gas absorption tower 2; it is used to make the treated gas pass through the ammonia gas absorption packing 21 for treatment multiple times to improve the absorption effect.

[0047] A replacement device for the ammonia gas absorption packing 21 is arranged outside the ammonia gas absorption tower 2. The packing replacement device includes a vertically arranged vertical telescopic rod 208. A cylinder 2010 for providing power for the telescopic movement is arranged on the vertical telescopic rod 208. The piston end of the cylinder 2010 is provided with a first slider 209. A driven rotary block 2013 is arranged on the first slider 209. Two first telescopic rods 2014 are symmetrically arranged on the rotary block 2013. The end of the first telescopic rod 2014 is connected to a second telescopic rod 2015 facing the ammonia gas absorption tower 2; the end of the second telescopic rod 2015 is provided with a clamping plate 2017; The side wall of the ammonia absorption tower 2 is provided with a feed inlet 202, and vertical through limiting rings 2023 are arranged on both sides of the feed inlet 202; a sealing door 203 capable of opening outward is arranged on the feed inlet 202; inside the ammonia absorption tower 2, a limiting cylinder 204 is fixed on the sealing door 203, and a reduced-diameter structure 205 is arranged in the middle of the limiting cylinder 204 in the height direction, and the ammonia absorption packing 21 is placed above the reduced-diameter structure 205; second sliders 2020 capable of sliding up and down are arranged on both sides of the sealing door 203, connecting rods 2021 are arranged at the upper and lower ends of the second sliders 2020 and are bent towards the limiting rings 2023, and the ends of the connecting rods 2021 are further bent relatively, so that the second sliders 2020 form a C-shaped structure symmetric up and down, and the notch of the C-shaped structure is close to the side wall of the ammonia absorption tower 2; the ends of the C-shaped structure are insertion rods 2022, and the insertion rods 2022 can be inserted into the limiting rings 2023.

[0048] The rotating block 2013 can rotate the two first telescopic rods 2014 in a plane perpendicular to the diameter of the ammonia absorption tower 2. The rotating block 2013 is driven by the first motor 2012, and both the first telescopic rod 2014 and the second telescopic rod 2015 are electrically driven.

[0049] A support rod 206 extending towards the vertical telescopic rod 208 is arranged below the feed inlet 202 to adjust the relative heights of the first telescopic rod 2014, the second telescopic rod 2015 and the clamping plate 2017 relative to the sealing door 203 for accurate positioning.

[0050] The clamping plate 2017 is provided with a clamping groove 2018, and a clamping block 2024 engaging with the shape of the clamping groove 2018 is arranged on the outer side of the C-shaped structure, so that the clamping plate 2017 can clamp the C-shaped structure to realize the operation of the second slider 2020.

[0051] The second slider 2020 is installed on the bushing 2019 of the sealing door 203, and the bushing 2019 is arranged at the center of the sealing door 203 in the height direction.

[0052] When replacing the ammonia absorption filler 21, the vertical telescopic rod 208 controls the height of the clamping plate 2017 to be the same as that of the second slider 2020, causing the first telescopic rod 2014 and the second telescopic rod 2015 to move, so that the engaging groove 2018 on the clamping plate 2017 clamps the engaging block 2024 of the second slider 2020; then the vertical telescopic rod 208 is lifted to disengage the limiting ring 2023 from the C-shaped structure; then the second telescopic rod 2015 is shortened to draw out the sealing door 203. Since the limiting cylinder 204 is fixed to the sealing door 203, the limiting cylinder 204 and the ammonia absorption filler 21 on the limiting cylinder 204 are synchronously drawn out; a new ammonia absorption filler is installed under the limiting cylinder 204; the sealing door 203 is rotated 180° up and down by using the rotating block 2013, so that the whole formed by the sealing door 203 and the limiting cylinder 204 slides down along the second slider 2020, causing the old ammonia absorption filler to flip to the lower side and fall off under the action of inertia, and the new ammonia absorption filler to flip to the upper side and reach the reduced-diameter structure 205 position; the second telescopic rod 2015 extends to insert the sealing door 203 into the ammonia absorption tower 2, and the limiting ring 2023 enters the notch of the C-shaped structure; then the vertical telescopic rod 208 descends, and after the insertion rod 2022 at the upper end of the C-shaped structure is inserted into the limiting ring 2023, the first telescopic rod 2014 is extended to separate the engaging groove 2018 on the clamping plate 2017 from the engaging block 2024 on the second slider 2020, so that the sealing door 203 loaded with the new ammonia absorption filler is fixed to the ammonia absorption tower 2 again, completing the replacement of the ammonia absorption filler 21.

[0053] The waste liquid concentrated ammonia treatment method of the waste liquid concentrated ammonia absorption tower venting device of this embodiment includes the following processes: The non-condensable gases in the first-effect evaporation chamber and the second-effect evaporation chamber enter the ammonia absorption tower 2, and the ammonia components in the non-condensable gases are absorbed by the ammonia absorption filler 21; the volatile gases in the condensate storage tank 1 and the gases discharged from the ammonia absorption tower 2 are mixed in the discharge pipe 29 and then discharged to the atmosphere after being treated by the alkali recovery furnace 4, the dust removal filter cartridge 6, the denitration tower 7 and the desulfurization tower 8; since the waste gas in the discharge pipe 29 contains both sulfur dioxide and ammonia, in the desulfurization tower 8, the sulfur dioxide in the waste gas is absorbed to generate sulfates or sulfuric acid, and the purified gas is discharged to the atmosphere through the exhaust pipe 81 to ensure compliance with the emission standards (the sulfur dioxide in the waste gas mainly comes from the waste liquid concentration process itself, especially the sulfides (such as sulfates, sulfites, organic sulfur compounds, etc.) contained in the waste liquid are decomposed or oxidized by heat during the evaporation and concentration process).

[0054] If the ammonia concentration in the gas discharged from the ammonia absorption tower 2 and the volatile gas in the condensate storage tank 1 meets the standard after mixing, it is directly discharged through the second control valve 25 from the opening of the discharge pipe 29; to simplify the treatment process, when the ammonia absorption packing 21 needs to be replaced or the ammonia concentration does not meet the standard due to unstable process, the second control valve 25 is closed and it is no longer discharged from the opening of the discharge pipe 29, but undergoes a complete treatment process.

[0055] The first input pipe 13 conveys nitrogen into the upper blind pipe 12 of the condensate storage tank to increase the internal air pressure of the condensate storage tank 1 to be greater than the air pressure in the discharge pipe 29 and avoid the explosion risk.

[0056] Inside the ammonia absorption tower 2, the gas above the ammonia absorption packing 21 is introduced below the ammonia absorption packing 21 through the circulation pump 211 outside the ammonia absorption tower 2 and circulates through the ammonia absorption packing 21 for treatment.

[0057] The ammonia water tank 26 is connected to the chimney 24 through the second inlet pipe 27, and a third control valve 28 is provided on the second inlet pipe 27.

[0058] Specifically, the specifications and treatment effects of each device in this embodiment are as follows: The capacity of the condensate storage tank 1 is 10 m³, the working pressure is 0.1 - 0.2 MPa, and the working temperature is 50 - 70°C.

[0059] The height of the overflow pipe 11 is 8 m (calculated from the bottom of the condensate storage tank 1).

[0060] The nitrogen input volume is 10 - 20 L / min (regulated by the first control valve 14).

[0061] The height of the ammonia absorption tower 2 is 15 m and the tower diameter is 2 m.

[0062] The ammonia absorption packing 21 is ceramic ring packing or plastic Pall ring packing.

[0063] The flow rate of the circulation pump 211 is 5 - 10 m³ / h and the head is 20 - 30 m.

[0064] The ammonia absorption rate is 95% - 98%.

[0065] The capacity of the ammonia water tank 26 is 2 m³.

[0066] The treatment capacity of the alkali recovery furnace 4 is 500 - 1000 Nm³ / h, the working temperature is 800 - 1000°C, the ammonia recovery rate is 90% - 95%, and the alkali recovery efficiency is 85% - 90%.

[0067] The filtration efficiency of the dust removal filter cartridge 6 is 99.9% (particle diameter ≥ 0.5 µm), and the pressure drop < 500 Pa The material of the dust removal filter cartridge 6 is polyester fiber or fiberglass.

[0068] The denitration efficiency of the denitration tower 7 is 90%-95%, the catalyst type is SCR catalyst (selective catalytic reduction), the catalyst life is 3-5 years, and the operating temperature is 300-400 °C.

[0069] The desulfurization efficiency of the desulfurization tower 8 is 95%-98%, the desulfurizing agent type is limestone or calcium hydroxide, and the operating temperature is 50-70 °C.

[0070] The emission standard of the exhaust pipe 81 is that the SO2 concentration is <50 mg / Nm³.

[0071] The air volume of the first blower 5 is 1000-1500 m³ / h, the air pressure is 2000-3000 Pa, and the power is 15-20 kW.

[0072] The air volume of the second blower 9 is 1500-2000 m³ / h, the air pressure is 3000-4000 Pa, and the power is 20-25 kW.

[0073] The fifth control valve 51 is used to control the air intake of the blower 5.

[0074] The sixth control valve 16 is used to regulate the emission rate of the volatile gas in the condensate storage tank 1.

[0075] The gas discharged from the exhaust pipe 81 is detected as follows: Ammonia emission concentration: <20 mg / Nm³.

[0076] Nitrogen oxide emission concentration: <100 mg / Nm³.

[0077] Particulate matter emission concentration: <10 mg / Nm³.

[0078] Sulfur dioxide emission concentration: <50 mg / Nm³.

[0079] The system parameters are as follows: System pressure: 0.1-0.3 MPa.

[0080] System temperature: 50-100 °C (according to different equipment sections).

[0081] The ammonia concentration in the ammonia absorption tower 2 is 500-1000 ppm at the inlet and <20 ppm at the outlet.

[0082] Equipment maintenance requirements: Dust removal filter cartridge 6 replacement cycle: Check every 3 months and replace if necessary. Denitration tower 7 catalyst replacement cycle: Replace every 3-5 years.

[0083] Desulfurization tower 8 desulfurizer replacement cycle: Replace once every 6 months.

[0084] Ammonia leakage detection: Install ammonia detectors near the ammonia absorption tower 2 and the ammonia water tank 26, and the alarm concentration is 50 ppm.

[0085] Emergency discharge: When the system pressure is too high, perform emergency discharge through the discharge pipe 29 of the chimney 24 to ensure system safety.

[0086] By setting up this venting device, it is ensured that: Energy consumption of the circulation pump 211: 5 - 10 kW Energy consumption of the first air blower 5: 15 - 20 kW Energy consumption of the second air blower 9: 20 - 25 kW Energy consumption of the alkali recovery furnace 4: 50 - 100 kW Total system energy consumption: Approximately 100 - 150 kW Ammonia recovery amount: Approximately 100 - 200 tons of ammonia can be recovered annually, reducing ammonia emissions.

[0087] Alkali recovery amount: Approximately 500 - 1000 tons of alkali solution can be recovered annually, reducing alkali solution consumption.

[0088] Reduction of pollutant emissions: Approximately 50 - 100 tons of nitrogen oxides and approximately 20 - 50 tons of sulfur dioxide emissions are reduced annually.

[0089] The above are only the preferred embodiments of the present application and are not used to limit the present application. For those skilled in the art, various changes and modifications can be made to the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included within the protection scope of the present application.

Claims

1. A waste liquid concentrating ammonia absorption tower venting device, characterized in that, It includes an ammonia absorption tower, an alkali recovery furnace, a denitration tower and a desulfurization tower connected in sequence; the ammonia absorption tower and the alkali recovery furnace are communicated through a discharge pipe; a condensate storage tank communicating with the second effect evaporation chamber is communicated with the discharge pipe; the ammonia absorption tower is respectively communicated with the first effect evaporation chamber and the second effect evaporation chamber; ammonia absorption packing is arranged in the ammonia absorption tower.

2. The waste liquid concentrating ammonia absorption tower venting device according to claim 1, characterized in that, The discharge pipe is communicated with an ammonia water tank; Or, a dust collector is arranged between the alkali recovery furnace and the denitration tower; Or, a first air blowing device is arranged on the discharge pipe, and a second air blowing device is arranged between the denitration tower and the desulfurization tower.

3. The waste liquid concentration ammonia absorption tower venting device according to claim 1, characterized in that, The condensate storage tank is communicated with a first input pipe, and the first input pipe is used for inputting nitrogen; Or, an opening leading to the atmosphere is arranged on the discharge pipe.

4. The waste liquid concentrating ammonia absorption tower venting device according to claim 1, characterized in that, The cavity above the ammonia absorption packing and the cavity below the ammonia absorption packing in the ammonia absorption tower are communicated through a circulating pump outside the ammonia absorption tower.

5. The waste liquid concentrating ammonia absorption tower venting device according to claim 1, characterized in that An ammonia absorption packing replacement device is arranged outside the ammonia absorption tower. The packing replacement device includes a vertically arranged vertical telescopic rod. A driven rotating block is arranged on the vertical telescopic rod. Two first telescopic rods are symmetrically arranged on the rotating block. The ends of the first telescopic rods are connected with second telescopic rods facing the ammonia absorption tower; clamping plates are arranged at the ends of the second telescopic rods; a feed inlet is arranged on the side wall of the ammonia absorption tower. Vertical limiting rings are arranged on both sides of the feed inlet; a sealing door capable of opening outward is arranged on the feed inlet; inside the ammonia absorption tower, a limiting cylinder is fixed on the sealing door. A reduced diameter structure is arranged in the middle of the height direction of the limiting cylinder. The ammonia absorption packing is placed above the reduced diameter structure; second sliders capable of sliding up and down are arranged on both sides of the sealing door. The upper and lower ends of the second sliders are respectively provided with C-shaped structures that are bent outward and further bent relatively and are symmetric up and down. The notch of the C-shaped structure is close to the side wall of the ammonia absorption tower. The end close to the C-shaped structure is inserted into the limiting ring.

6. The waste liquid concentration ammonia absorption tower venting device according to claim 5, characterized in that, A support rod extending towards the vertical telescopic rod is arranged below the feed inlet; Or, a clamping groove is arranged on the clamping plate, and a clamping block with a shape that engages with the clamping groove is arranged on the outer side of the C-shaped structure; Or, the second slider is installed on a shaft sleeve of the sealing door, and the shaft sleeve is arranged at the center of the height direction of the sealing door.

7. The waste liquid concentrating ammonia absorption tower venting device according to any one of claims 5-6, characterized in that, The method for replacing the ammonia absorption packing includes: controlling the height of the clamping plate by the vertical telescopic rod to be the same as that of the second slider, moving the first telescopic rod and the second telescopic rod to make the clamping plate clamp the second slider; then lifting the vertical telescopic rod to make the limiting ring break away from the C-shaped structure; shortening the second telescopic rod to draw out the sealing door; installing a new ammonia absorption packing below the limiting cylinder; using the rotating block to rotate the sealing door up and down to turn the old ammonia absorption packing to the lower side and fall off, and turn the new ammonia absorption packing to the upper side; elongating the second telescopic rod to insert the sealing door into the ammonia absorption tower and make the limiting ring enter the notch of the C-shaped structure; then lowering the vertical telescopic rod to make the upper end of the C-shaped structure insert into the limiting ring, and elongating the first telescopic rod to separate the clamping plate and the second slider to complete the replacement of the ammonia absorption packing.

8. A method for treating waste liquid concentrated ammonia of the waste liquid concentrated ammonia absorption tower venting device according to any one of claims 1-7, characterized in that, It includes the following processes: The non-condensable gases in the first-effect evaporation chamber and the second-effect evaporation chamber enter the ammonia absorption tower, and the ammonia components in the non-condensable gases are absorbed; the volatile gases in the condensate storage tank are mixed with the gases discharged from the ammonia absorption tower in the discharge pipe and then discharged to the atmosphere after passing through the treatment of the alkali recovery furnace, the denitration tower and the desulfurization tower.

9. The waste liquid concentrated ammonia treatment method according to claim 8, characterized in that, If the ammonia concentration reaches the standard after the gases discharged from the ammonia absorption tower are mixed with the volatile gases in the condensate storage tank, it is directly discharged from the opening of the discharge pipe; when the ammonia absorption packing needs to be replaced or the ammonia concentration does not reach the standard due to unstable process, it is no longer discharged from the opening of the discharge pipe, but undergoes a complete treatment process.

10. The waste liquid concentrated ammonia treatment method according to claim 8, characterized in that, The first conveying pipe conveys nitrogen into the condensate storage tank to increase the internal air pressure of the condensate storage tank to be greater than the air pressure in the discharge pipe; Or, inside the ammonia absorption tower, the gases above the absorption packing are introduced below the absorption packing through a circulating pump outside the ammonia absorption tower for circulating treatment.

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