Chemical fertilizer plant wastewater comprehensive treatment system
By combining the decolorization unit, phosphorus removal unit, ammonia nitrogen blowing unit and biochemical treatment unit, the problem of difficult to treat the wastewater of the fertilizer plant in traditional systems is solved, and efficient recycling and resource conservation of wastewater is achieved.
Patent Information
- Application Number
- CN202421794906.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-07-26
- Publication Date
- 2025-07-22
- Estimated Expiration
- 2034-07-26
AI Technical Summary
Traditional wastewater treatment systems are difficult to effectively remove complex pollutants in the wastewater of fertilizer plants, making it difficult for water quality to meet the standards of reuse and causing waste of water resources.
A combined treatment system of decolorization unit, phosphorus removal unit, ammonia nitrogen blowing unit and biochemical treatment unit is adopted, including an internal electrolytic reaction tower, a pH adjustment container, a settlement separation tower, an ammonia nitrogen blowing tower and a biochemical treatment unit. The colored components, phosphorus elements and nitrogen in the wastewater are removed through internal electrolytic reaction, pH adjustment, ammonia nitrogen blowing and biochemical treatment.
It has achieved effective removal of various pollutants in the wastewater of fertilizer plants, met recycling standards, saved water resources and reduced fertilizer production costs.
Smart Images
Figure CN223134273U_ABST
Abstract
Description
Technical Field
[0001] This application relates to the technical field of wastewater treatment, and particularly to a comprehensive wastewater treatment system for a fertilizer plant. Background Art
[0002] In modern agricultural production, fertilizers, as a key factor in increasing crop yields, have an expanding manufacturing industry scale. However, during the fertilizer production process, a large amount of wastewater is generated. This wastewater is rich in ammonia nitrogen, phosphorus, organic pollutants, and other contaminants. If it is directly discharged without proper treatment, it not only seriously threatens the ecological balance of natural water bodies and causes environmental disasters such as water blooms, but also results in a great waste of precious water resources.
[0003] Traditional wastewater treatment systems, such as single physical precipitation or chemical neutralization, often have difficulty effectively removing the complex combination of contaminants in the wastewater of fertilizer plants, and the treated water quality is difficult to meet the reuse standard. Utility Model Content
[0004] This application provides a new comprehensive wastewater treatment system for a fertilizer plant, which can better achieve wastewater treatment.
[0005] According to one aspect of this application, in one embodiment, a comprehensive wastewater treatment system for a fertilizer plant is provided, including: a decolorization unit, a phosphorus removal unit, an ammonia nitrogen stripping unit, and a biochemical treatment unit.
[0006] The decolorization unit includes an internal electrolysis reaction tower. Inside the internal electrolysis reaction tower, a packing layer and a water distribution device are provided. The water distribution device is located below the packing layer and is used to evenly distribute the production wastewater to the packing layer. The packing layer is used for the internal electrolysis reaction decolorization of the production wastewater.
[0007] The phosphorus removal unit includes a pH value adjustment container and a sedimentation separation tower. The pH value adjustment container is used to adjust the pH value of the decolorized production wastewater. The sedimentation separation tower is connected to the pH value adjustment container and is used to separate the phosphorus-containing sediment in the production wastewater.
[0008] The ammonia nitrogen stripping unit includes a collection pool and an ammonia nitrogen stripping tower. The collection pool is connected to the sedimentation separation tower and is used to collect the production wastewater after phosphorus removal. The ammonia nitrogen stripping tower includes a tower body and an atomization device. The atomization device is arranged inside the tower body and is used to atomize the production wastewater after phosphorus removal. The tower body has an air inlet, and the air inlet is used to introduce stripping gas to perform secondary ammonia nitrogen stripping on the production wastewater after phosphorus removal.
[0009] The biochemical treatment unit is used to treat the nitrogen and part of the phosphorus elements in the production wastewater after secondary ammonia nitrogen stripping.
[0010] In some embodiments, three internal electrolysis reaction towers are provided, and the decolorization unit further includes a plurality of connecting pipes, and the plurality of connecting pipes connect the three internal electrolysis reaction towers in series or in parallel.
[0011] And / or, the decolorization unit further includes a circulation pump, and the circulation pump is used to return the decolorized production wastewater to the internal electrolysis reaction tower to perform cyclic decolorization treatment on the production wastewater.
[0012] In some embodiments, an air blowing port and a slag discharging port are provided at the lower part of the internal electrolysis reaction tower. The air blowing port is used to introduce air into the internal electrolysis reaction tower to clean the mud and slag on the packing layer, and the slag discharging port is used to discharge the mud and slag.
[0013] In some embodiments, the pH value adjustment container includes a lime dissolving barrel and a caustic soda dissolving barrel. The lime dissolving barrel and the caustic soda dissolving barrel are used to contain quicklime and caustic soda. The lime dissolving barrel and the caustic soda dissolving barrel are both provided with a water injection port and a water outlet. The water outlet of the lime dissolving barrel is communicated with the water injection port of the caustic soda dissolving barrel, and the water injection port of the lime dissolving barrel is used to inject the decolorized production wastewater.
[0014] In some embodiments, the ammonia nitrogen stripping unit further includes an ammonia nitrogen stripping tank. The inlet of the ammonia nitrogen stripping tank is connected to the pH value adjustment container, and the outlet of the ammonia nitrogen stripping tank is connected to the sedimentation and separation tower. The ammonia nitrogen stripping tank is used to introduce air to perform primary ammonia nitrogen stripping on the production wastewater.
[0015] In some embodiments, the phosphorus removal unit includes a chemical dosing device. The chemical dosing device is arranged between the ammonia nitrogen stripping tank and the sedimentation and separation tower, and the chemical dosing device is used to add a flocculant to the production wastewater after primary ammonia nitrogen stripping.
[0016] In some embodiments, the ammonia nitrogen stripping unit includes a circulation pipe. The circulation pipe is connected between the water outlet of the ammonia nitrogen stripping tower and the collection tank, and the circulation pipe is used to re-transport the production wastewater treated by the ammonia nitrogen stripping tower back to the collection tank.
[0017] In some embodiments, the biochemical treatment unit includes: a denitrification tank, a nitrification tank and an MBR tank. The denitrification tank, the nitrification tank and the MBR tank are connected in sequence. The denitrification tank and the nitrification tank are used to remove nitrogen and part of phosphorus elements in the production wastewater after secondary ammonia nitrogen stripping, and the MBR tank is used to intercept the sludge in the production wastewater.
[0018] In some embodiments, the comprehensive treatment system for chemical fertilizer plant wastewater includes a pressure filtration device. The pressure filtration device is connected to the sludge outlet of the sedimentation and separation tower. The pressure filtration device includes a filtrate outlet, and the filtrate outlet is communicated with the ammonia nitrogen stripping tank.
[0019] In some embodiments, the integrated fertilizer plant wastewater treatment system includes a sewage station mixing tank and a domestic sewage tank. The sewage station mixing tank is arranged between the ammonia nitrogen stripping unit and the biochemical treatment unit. The domestic sewage tank is connected to the sewage station mixing tank. The sewage station mixing tank is used to mix domestic sewage and production wastewater treated by the ammonia nitrogen stripping unit.
[0020] According to the integrated fertilizer plant wastewater treatment system of the above embodiments, the decolorization unit uses an internal electrolysis reaction tower to remove the colored components in the production wastewater. The phosphorus removal unit adjusts the pH value of the production wastewater to precipitate and separate the phosphorus element therein. The ammonia nitrogen stripping unit can strip and remove the free ammonia nitrogen element in the production wastewater, and the stripped ammonia gas, etc. can also be used as raw materials for fertilizer production; the biochemical treatment unit removes the remaining nitrogen, phosphorus elements and organic pollutants in the production wastewater through microbial flora; the above process realizes the removal of various pollutants in the production wastewater, can meet the standard of recycling the production wastewater, saves water resources and reduces the cost of fertilizer production. Description of the Drawings
[0021] Figure 1 It is a schematic diagram of an embodiment of the integrated fertilizer plant wastewater treatment system of the present utility model;
[0022] Figure 2 is Figure 1 a schematic structural diagram of the internal electrolysis reaction tower in
[0023] Figure 3 is Figure 1 a schematic structural diagram of the MBR tank in
[0024] Reference Numerals:
[0025] 1. Internal electrolysis reaction tower; 11. Packing layer; 12. Water distribution device; 13. Backwashing port; 14. Slag discharge port; 2. Ammonia nitrogen stripping tank; 3. Sedimentation and separation tower; 4. Collection tank; 5. Ammonia nitrogen stripping tower; 6. Denitrification tank; 7. Nitrification tank; 8. MBR tank; 9. Emergency tank; 10. Sewage station mixing tank. Detailed Embodiments
[0026] The present application will be further described in detail below through specific embodiments in conjunction with the accompanying drawings. Similar elements in different embodiments are denoted by related similar element numbers. In the following embodiments, many detailed descriptions are provided to enable a better understanding of the present application. However, those skilled in the art can easily recognize that some of the features can be omitted in different situations, or can be replaced by other elements, materials, or methods. In some cases, some operations related to the present application are not shown or described in the specification, which is to avoid the core part of the present application being overwhelmed by excessive descriptions. For those skilled in the art, it is not necessary to describe these related operations in detail, and they can fully understand the related operations based on the descriptions in the specification and the general technical knowledge in the art.
[0027] In addition, the features, operations, or characteristics described in the specification can be combined in any appropriate manner to form various embodiments, and the operation steps involved in each embodiment can also be reordered or adjusted in a manner obvious to those skilled in the art. Therefore, the specification and the drawings are only for clearly describing a certain embodiment, and do not mean that they are essential components and / or sequences.
[0028] The serial numbers assigned to the components herein, such as "first", "second", etc., are only used to distinguish the described objects and do not have any sequential or technical meanings. And the "connection" and "coupling" mentioned in the present application, unless otherwise specified, both include direct and indirect connection (coupling).
[0029] In the embodiment of the wastewater comprehensive treatment system for a chemical fertilizer plant of the present utility model, the colored components and phosphorus elements in the production wastewater are first removed through the decolorization unit and the phosphorus removal unit, and then the ammonia nitrogen elements in the production wastewater are removed through the ammonia nitrogen stripping unit and the biochemical treatment unit; the production wastewater after treatment can meet the standard for recycling, solving the problem of water resource waste caused by imperfect treatment of production wastewater.
[0030] As Figure 1 , 2 shown, the embodiment of the wastewater comprehensive treatment system for a chemical fertilizer plant of the present utility model includes: a decolorization unit, a phosphorus removal unit, an ammonia nitrogen stripping unit, and a biochemical treatment unit.
[0031] As Figure 2 shown, the decolorization unit includes an internal electrolysis reaction tower 1. Inside the internal electrolysis reaction tower 1, there is a packing layer 11 and a water distribution device 12. The water distribution device 12 is located below the packing layer 11 and is used to evenly distribute the production wastewater to the packing layer 11. The packing layer 11 is used for the internal electrolysis reaction decolorization of the production wastewater. The setting of the water distribution device 12 can increase the contact area between the production wastewater and the packing layer 11 and improve the reaction rate.
[0032] In a specific embodiment, the pH value of the production wastewater can be adjusted to 3 - 4 by adding acid solution thereto to meet the conditions for the occurrence of the internal electrolysis reaction, and then the production wastewater is fed into the internal electrolysis reaction tower 1. For example, when the flow rate of the production wastewater is stable, the amount of acid solution added to the production wastewater can be adjusted by controlling the flow rate of the acid addition pump, thereby precisely adjusting the pH value of the production wastewater.
[0033] The packing layer 11 can be filled with iron-carbon packing. In the above acidic environment, the iron-carbon packing can generate an electrochemical reaction to destroy the dye molecules in the production wastewater, and at the same time remove some organic pollutants and metal ions in the production wastewater.
[0034] As Figure 1 shown, in one embodiment, the phosphorus removal unit can include a pH value adjustment container and a sedimentation separation tower 3. The pH value adjustment container is used to adjust the pH value of the decolorized production wastewater, and the sedimentation separation tower 3 is connected to the pH value adjustment container and is used to separate the phosphorus-containing sediment in the production wastewater.
[0035] Quicklime and caustic soda can be used to adjust the pH value of the production wastewater. Specifically, quicklime and caustic soda can be added to the pH value adjustment container, and then the decolorized production wastewater is added to the pH value adjustment container to adjust the pH value of the decolorized production wastewater to above 11. Under the above pH value conditions, the calcium ions generated after the reaction of quicklime can react with the phosphate in the production wastewater to form a phosphorus-containing sediment that is insoluble in water, such as hydroxyapatite. Then the above production wastewater is fed into the sedimentation separation tower 3. In the sedimentation separation tower 3, the phosphorus-containing sediment settles at the bottom of the sedimentation separation tower 3, and the upper-layer production wastewater overflows and enters the collection pool 4.
[0036] As Figure 1 shown, the ammonia nitrogen stripping unit includes a collection pool 4 and an ammonia nitrogen stripping tower 5. The collection pool 4 is connected to the sedimentation separation tower 3 and is used to collect the production wastewater after phosphorus removal. The ammonia nitrogen stripping tower 5 includes a tower body and an atomizing device. The atomizing device is arranged in the tower body and is used to atomize the production wastewater after phosphorus removal. The tower body has an air inlet, and the air inlet is used to introduce stripping gas to perform secondary ammonia nitrogen stripping on the production wastewater after phosphorus removal.
[0037] The stripping gas can utilize the boiler flue gas in the chemical fertilizer production process. Specifically, an atomization device can be arranged inside the ammonia stripping tower 5. The production wastewater is sent into the ammonia atomization device, and at the same time, the boiler flue gas is sent from the bottom of the ammonia stripping tower 5. The boiler flue gas flows countercurrently to the atomized production wastewater and reacts. The free ammonia in the production wastewater is carried away by the boiler flue gas and can be further recycled. The production wastewater falling to the bottom of the ammonia stripping tower 5 can be adjusted with alkali to a pH value above 11 and then sent back into the atomization device of the ammonia stripping tower 5 for recycling. Using the boiler flue gas for ammonia stripping of the production wastewater can, on the one hand, remove the ammonia nitrogen element in the production wastewater, and on the other hand, achieve desulfurization and dust removal of the boiler flue gas.
[0038] The biochemical treatment unit is used to treat the nitrogen and some phosphorus elements in the production wastewater after secondary ammonia stripping. The biochemical treatment unit can utilize the microbial flora in the activated sludge to convert the nitrogen in the production wastewater into nitrogen and remove it, while consuming the organic pollutants in the water.
[0039] The above process realizes the removal of various pollutants in the production wastewater, can meet the standard of recycling the production wastewater, saves water resources and reduces the cost of chemical fertilizer production.
[0040] In some embodiments, as Figure 1 、 2 shown, there are three internal electrolysis reaction towers 1 provided, and the decolorization unit further includes multiple connecting pipes, and the multiple connecting pipes connect the three internal electrolysis reaction towers 1 in series or in parallel. The decolorization unit further includes a circulation pump, and the circulation pump is used to return the decolorized production wastewater to the internal electrolysis reaction tower 1 for circulating decolorization treatment of the production wastewater. Setting the circulation pump can realize multiple circulating decolorization treatments of the production wastewater and enhance the decolorization until the effect of complete decolorization is achieved.
[0041] When the color of the production wastewater is relatively deep, the three internal electrolysis reaction towers 1 are connected in series, and the production wastewater flows through the three internal electrolysis reaction towers 1 in sequence, as Figure 2 shown by the solid line circulation path in. In the series state, the production wastewater is decolorized by passing through the three internal electrolysis reaction towers 1 in sequence, and the decolorization effect is better.
[0042] When the color of the production wastewater is relatively light, the multiple internal electrolysis reaction towers 1 are connected in parallel, and the production wastewater is divided into three paths and flows into the three internal electrolysis reaction towers 1 respectively, as Figure 2 shown by the dotted line circulation path in. In the parallel state, the three internal electrolysis reaction towers 1 treat the production wastewater simultaneously, and the treatment rate is higher.
[0043] In some embodiments, as Figure 1 、 2As shown in the figure, an air blowing port 13 and a slag discharging port 14 are provided at the lower part of the internal electrolysis reaction tower 1. The air blowing port 13 is used to introduce air into the internal electrolysis reaction tower 1 to clean the sludge on the packing layer 11, and the slag discharging port 14 is used to discharge the sludge.
[0044] In a specific embodiment, when there is water in the internal electrolysis reaction tower 1, a vibrating crusher can be used to vibrate the packing layer 11 to make the sludge in its pores fall off. At the same time, compressed air is introduced into the internal electrolysis reaction tower 1 through the air blowing port 13 to further promote the falling off of the sludge. Finally, the sludge is discharged through the slag discharging port 14, and new packing can be supplemented into the packing layer 11. The above settings can increase the contact area between the packing and the production wastewater, and improve the decolorization rate and decolorization effect.
[0045] In some embodiments, as Figure 1 shown, the pH value adjustment container includes a lime dissolution barrel and a caustic soda dissolution barrel. The lime dissolution barrel and the caustic soda dissolution barrel are used to contain quicklime and caustic soda. The lime dissolution barrel and the caustic soda dissolution barrel are both provided with a water injection port and a water outlet. The water outlet of the lime dissolution barrel is communicated with the water injection port of the caustic soda dissolution barrel, and the water injection port of the lime dissolution barrel is used to inject the decolorized production wastewater.
[0046] In a specific embodiment, the dosages of quicklime and caustic soda can be determined according to the amount of production wastewater that the lime dissolution barrel and the caustic soda dissolution barrel can hold. Then, the production wastewater is first injected into the lime dissolution barrel and stirred to adjust its pH value to above 10. Then, the production wastewater in the lime dissolution barrel is added to the caustic soda dissolution barrel, and its pH value is further adjusted to above 11.
[0047] In some embodiments, as Figure 1 shown, the ammonia nitrogen stripping unit further includes an ammonia nitrogen stripping pool 2. The inlet of the ammonia nitrogen stripping pool 2 is connected to the pH value adjustment container, and the outlet of the ammonia nitrogen stripping pool 2 is connected to the sedimentation and separation tower 3. The ammonia nitrogen stripping pool 2 is used to introduce air to perform primary ammonia nitrogen stripping on the production wastewater.
[0048] Specifically, the primary ammonia nitrogen stripping plays a role in preliminarily treating the production wastewater for ammonia nitrogen stripping, reducing the free ammonia in the production wastewater, and reducing the burden of secondary ammonia nitrogen stripping. In addition, the primary stripping can stir the production wastewater to promote the mixing of quicklime, caustic soda and the production wastewater, which is beneficial to the separation of phosphorus-containing sediment in the sedimentation and separation tower 3 for the production wastewater.
[0049] In some embodiments, as Figure 1 shown, the phosphorus removal unit includes a dosing device. The dosing device is arranged between the ammonia nitrogen stripping pool 2 and the sedimentation and separation tower 3, and the dosing device is used to add a flocculant to the production wastewater after primary ammonia nitrogen stripping.
[0050] Specifically, the chemical dosing device can be arranged on the pipeline connecting the ammonia nitrogen stripping tank 2 and the sedimentation and separation tower 3. The flocculant can be cationic polyacrylamide. Adding the flocculant can adsorb the particles in the production wastewater and form larger sediments, which is beneficial to the sedimentation of phosphorus-containing substances and improves the phosphorus removal effect.
[0051] In some embodiments, as Figure 1 shown, the ammonia nitrogen stripping unit includes a circulation pipe, which is connected between the water outlet of the ammonia nitrogen stripping tower 5 and the collection tank 4. The circulation pipe is used to re-transport the production wastewater treated by the ammonia nitrogen stripping tower 5 back to the collection tank 4. Setting the circulation pipe enables the production wastewater to be stripped by the boiler flue gas multiple times, and the removal effect of ammonia nitrogen elements in the production wastewater is better.
[0052] In some embodiments, as Figure 1 shown, the biochemical treatment unit includes: a denitrification tank 6, a nitrification tank 7, and an MBR (Membrane Bio-Reactor) tank, that is, a membrane bioreactor. The denitrification tank 6, the nitrification tank 7, and the MBR tank 8 are connected in sequence. The denitrification tank 6 and the nitrification tank 7 are used to remove nitrogen and part of the phosphorus elements in the production wastewater after the secondary ammonia nitrogen stripping, and the MBR tank 8 is used to intercept the sludge in the production wastewater.
[0053] Specifically, the nitrification tank 7 and the denitrification tank 6 can be provided with activated sludge. The microbial flora in the activated sludge can convert the nitrogen in the production wastewater into nitrogen gas for removal, and at the same time consume the organic pollutants in the water. The following nitrification reaction occurs in the nitrification tank 7: first, under aerobic conditions, nitrite bacteria use oxygen as an electron acceptor to convert ammonia nitrogen into nitrite, and then nitrate bacteria convert nitrite into nitrate. The following denitrification reaction occurs in the denitrification tank 6: after the nitrification reaction is completed, denitrifying bacteria use various organic substrates as electron donors and nitrate or nitrite as electron acceptors to carry out anaerobic respiration, converting nitrate or nitrite into nitrogen gas. The entire biochemical process in the biochemical treatment unit revolves around the above two points to convert the ammonia nitrogen elements in the production wastewater into nitrogen gas for removal. After the nitrification tank 7 and the denitrification tank 6 operate for a period of time, some nutrients such as starch or other sugars can be added to them for the reproduction of the microbial flora.
[0054] The MBR tank also has a certain nitrification effect. After the water quality flows to the MBR tank, nitrification occurs again. The MBR tank 8 is equipped with a membrane module, and the membrane module can achieve solid-liquid separation and intercept the activated sludge in the production wastewater. The retained activated sludge still has a microbial flora and can be reused. For example: using the aeration conditions of the MBR tank also has a certain nitrification effect, thereby reducing the cost of wastewater treatment.
[0055] In some embodiments, a separation tower is additionally provided between the nitrification tank 7 and the MBR tank 8. An overflow pipe is arranged at the top of the separation tower, and the overflow water flows into the MBR tank 8, which is used to control the sludge volume in the MBR tank 8 to adjust the nitrification effect and simultaneously reduce the burden on the membrane module 83 in the MBR tank 8. A reflux pipe is arranged under the separation tower and respectively refluxes to the nitrification tank 7 and the mixing tank 10 of the sewage treatment station. The production wastewater refluxing to the mixing tank 10 of the sewage treatment station then flows into the denitrification tank 7. The biochemical effect is regulated through the reflux system of the separation tower body to achieve the effects of enhancing nitrification and denitrification. A reflux pipe is provided in the sedimentation tank 82 after the MBR tank 8 to make the water reflux to the mixing tank 10 of the sewage treatment station and then enter the denitrification tank 7, which is beneficial to improving the denitrification effect and enhancing the treatment capacity of the biochemical system.
[0056] The production wastewater serves a part of the purpose of anoxic denitrification in the separation tower, and then can be refluxed to the nitrification tank 7 through the reflux pipe, ultimately realizing a part of the cycle of nitrification and denitrification of the production wastewater among the separation tower, the sedimentation tank 82 and the nitrification tank 7.
[0057] In some embodiments, as Figure 3 shown, the MBR tank 8 includes an aeration tank 81 and a sedimentation tank 82. The aeration tank 81 is provided with a membrane module 83, an aeration disc 84 and a propeller 85. The membrane module 83 includes an MBR membrane and a membrane rack. The membrane rack fixes the MBR membrane at the middle height in the aeration tank 81 and immerses it in the production wastewater. The aeration disc 84 is located at the bottom of the aeration tank 81. Five groups of aeration discs 84 can be provided and correspond to five groups of membrane modules 83.
[0058] The membrane module 83 can filter the production wastewater and intercept the activated sludge in the MBR tank 8. The production wastewater filtered by the membrane module 83 can be discharged after passing the detection. Another part of the production wastewater is refluxed to the mixing tank 10 of the sewage treatment station after sedimentation and then enters the denitrification tank 6 for treatment. An inclined hopper 821 is arranged inside the sedimentation tank 82, and the inclined hopper 821 is used for sludge sedimentation. The sedimented sludge can be pushed out by the propeller 85 to avoid excessive sludge deposition affecting the sedimentation effect. The aeration disc 84 can introduce air into the MBR tank 8, which is beneficial to the reproduction of aerobic bacteria in the activated sludge and can treat the ammonia nitrogen and other organic matters in the production wastewater.
[0059] In some embodiments, as Figure 1 shown, the comprehensive wastewater treatment system of the fertilizer plant includes a pressure filtration device. The pressure filtration device is connected to the sludge outlet of the sedimentation and separation tower 3. The pressure filtration device includes a filtrate outlet, and the filtrate outlet is communicated with the ammonia nitrogen stripping tank 2.
[0060] In the sedimentation separation tower 3, the phosphorus-containing sediment settles at the bottom of the sedimentation separation tower 3. The phosphorus-containing sediment can be discharged through the sludge outlet to a pressure filtration device. The pressure filtration device performs pressure filtration on the phosphorus-containing sediment. The filter cake can be used for producing organic fertilizer, and the filtrate can be transported back to the ammonia nitrogen stripping tank 2 for subsequent treatment.
[0061] In some embodiments, as Figure 1 shown, the comprehensive treatment system for chemical fertilizer plant wastewater includes a sewage station mixing tank 10 and a domestic sewage tank. The sewage station mixing tank 10 is arranged between the ammonia nitrogen stripping unit and the biochemical treatment unit. The domestic sewage tank is connected to the sewage station mixing tank 10. The sewage station mixing tank 10 is used for mixing domestic sewage and the production wastewater treated by the ammonia nitrogen stripping unit.
[0062] The above uses specific examples to elaborate on the present invention, which is only used to help understand the present invention and is not intended to limit the present invention. For those skilled in the art of the present invention, according to the idea of the present invention, several simple deductions, deformations or substitutions can also be made.
Claims
1. An integrated wastewater treatment system for a chemical fertilizer plant, characterized in that, Comprising: A decolorization unit, the decolorization unit includes an internal electrolysis reaction tower, the inside of the internal electrolysis reaction tower is provided with a packing layer and a water distribution device, the water distribution device is located below the packing layer and is used to evenly distribute the production wastewater to the packing layer, and the packing layer is used for the production wastewater to carry out internal electrolysis reaction decolorization; A phosphorus removal unit, the phosphorus removal unit includes a pH adjustment container and a sedimentation separation tower, the pH adjustment container is used to adjust the pH value of the decolorized production wastewater, and the sedimentation separation tower is connected to the pH adjustment container and is used to separate the phosphorus-containing sediment in the production wastewater; An ammonia nitrogen stripping unit, the ammonia nitrogen stripping unit includes a collection tank and an ammonia nitrogen stripping tower, the collection tank is connected to the sedimentation separation tower and is used to collect the production wastewater after phosphorus removal, the ammonia nitrogen stripping tower includes a tower body and an atomization device, the atomization device is arranged in the tower body and is used to atomize the production wastewater after phosphorus removal, the tower body has an air inlet, and the air inlet is used to introduce stripping gas to carry out secondary ammonia nitrogen stripping on the production wastewater after phosphorus removal; And a biochemical treatment unit, the biochemical treatment unit is used to treat the nitrogen and part of the phosphorus elements in the production wastewater after secondary ammonia nitrogen stripping.
2. The comprehensive treatment system for chemical fertilizer plant wastewater according to claim 1, wherein There are three internal electrolysis reaction towers, and the decolorization unit further includes a plurality of connecting pipes, and the plurality of connecting pipes connect the three internal electrolysis reaction towers in series or in parallel. And / or, the decolorization unit further includes a circulation pump, and the circulation pump is used to return the decolorized production wastewater to the internal electrolysis reaction tower to carry out cyclic decolorization treatment on the production wastewater.
3. The comprehensive treatment system for chemical fertilizer plant wastewater according to claim 1, characterized in that, The lower part of the internal electrolysis reaction tower is provided with an air back-blowing port and a slag discharge port, the air back-blowing port is used to introduce air into the internal electrolysis reaction tower to clean the sludge on the packing layer, and the slag discharge port is used to discharge the sludge.
4. The comprehensive treatment system for chemical fertilizer plant wastewater according to claim 1, wherein, The pH adjustment container includes a lime dissolution barrel and a caustic soda dissolution barrel, the lime dissolution barrel and the caustic soda dissolution barrel are used to contain quicklime and caustic soda, the lime dissolution barrel and the caustic soda dissolution barrel are both provided with a water injection port and a water outlet, the water outlet of the lime dissolution barrel is communicated with the water injection port of the caustic soda dissolution barrel, and the water injection port of the lime dissolution barrel is used to inject the decolorized production wastewater.
5. The integrated treatment system for chemical fertilizer plant wastewater according to claim 1, characterized in that, The ammonia nitrogen stripping unit further includes an ammonia nitrogen stripping pool, the inlet of the ammonia nitrogen stripping pool is connected to the pH adjustment container, the outlet of the ammonia nitrogen stripping pool is connected to the sedimentation separation tower, and the ammonia nitrogen stripping pool is used to introduce air to carry out primary ammonia nitrogen stripping on the production wastewater.
6. The integrated wastewater treatment system for fertilizer plants according to claim 5, characterized in that, The phosphorus removal unit includes a dosing device, the dosing device is arranged between the ammonia nitrogen stripping pool and the sedimentation separation tower, and the dosing device is used to add a flocculant to the production wastewater after primary ammonia nitrogen stripping.
7. The integrated wastewater treatment system for chemical fertilizer plants according to claim 1, characterized in that, The ammonia nitrogen stripping unit includes a circulation pipe, the circulation pipe is connected between the water outlet of the ammonia nitrogen stripping tower and the collection tank, and the circulation pipe is used to re-transport the production wastewater treated by the ammonia nitrogen stripping tower back to the collection tank.
8. The integrated wastewater treatment system for fertilizer plants according to claim 1, wherein, The biochemical treatment unit includes: a denitrification tank, a nitrification tank, and an MBR tank. The denitrification tank, the nitrification tank, and the MBR tank are connected in sequence. The denitrification tank and the nitrification tank are used to remove nitrogen and part of phosphorus elements in the production wastewater after secondary ammonia stripping. The MBR tank is used to intercept sludge in the production wastewater.
9. The integrated wastewater treatment system for chemical fertilizer plants according to claim 5, wherein, It includes a pressure filtration device. The pressure filtration device is connected to the sludge outlet of the sedimentation and separation tower. The pressure filtration device includes a filtrate outlet, and the filtrate outlet is communicated with the ammonia stripping tank.
10. The comprehensive treatment system for chemical fertilizer plant wastewater according to any one of claims 1-9, characterized in that, It includes a sewage station mixing tank and a domestic sewage tank. The sewage station mixing tank is arranged between the ammonia stripping unit and the biochemical treatment unit. The domestic sewage tank is connected to the sewage station mixing tank. The sewage station mixing tank is used to mix domestic sewage and the production wastewater treated by the ammonia stripping unit.