Ammonia-nitrogen wastewater treatment method and equipment thereof

Abstract

The invention provides an ammonia-nitrogen wastewater treatment method which comprises the following steps: ammonia-nitrogen wastewater to be treated fully reacts with a first mixture to form a first treatment product, and the first mixture comprises iron powder, carbon powder and ferric tetraoxide; fully reacting the first treatment product with a second mixture to form a second treatment product, the second mixture comprising activated carbon, anthracite and quartz sand; ammonia gas in the second treatment product is removed in an air stripping mode, and the second treatment product is converted into a third treatment product; and cooling the third treatment product to normal temperature, discharging the third treatment product, converting the removed ammonia gas into ammonia water, and collecting the ammonia water. According to the technical scheme, the operation cost of ammonia-nitrogen wastewater treatment can be greatly reduced.

Description

Technical Field

[0001] This application relates to the field of semiconductor manufacturing, and particularly to a method and equipment for treating ammonia-nitrogen wastewater. Background Art

[0002] The integrated circuit industry requires a large amount of ammonia water, especially in the process sections such as cleaning, etching, and pH value adjustment of electronic devices. Therefore, a large amount of ammonia-nitrogen-containing wastewater is generated during the production process. However, only a small part of ammonia (NH3) in the ammonia-nitrogen-containing wastewater can be consumed, and most of it is diluted and polluted to become higher-concentration ammonia-nitrogen wastewater. Currently, the treatment process for ammonia-nitrogen wastewater is to heat and add sodium hydroxide to reduce the solubility of ammonia gas in water, and then blow off ammonia through a blower to separate ammonia from the wastewater, so as to ensure that the concentration of ammonia nitrogen in the discharged wastewater meets the discharge standard. The ammonia gas removed is adsorbed by sulfuric acid in a spray tower (2NH3 + H2SO4 = (NH4)2SO4). This process not only consumes a large amount of sulfuric acid but also generates a large amount of ammonium sulfate waste liquid, resulting in a high cost of the wastewater treatment process.

[0003] Moreover, the recycling value of ammonia nitrogen is not fully considered in this process, resulting in a waste of ammonia-nitrogen resources. Further, the ammonia-nitrogen wastewater contains pollutants such as hydrogen peroxide, organic matter, suspended solids, and colloids, resulting in the removed ammonia gas containing various impurities and unable to be directly recycled as industrial ammonia water. The conventional rectification and purification process is only applicable to large-scale ammonia water purification and is not applicable in this process. Therefore, a high-cost-effective and feasible ammonia-nitrogen wastewater treatment process and ammonia water recycling process need to be found. Summary of the Invention

[0004] To solve the above technical problems, this application provides a method for treating ammonia-nitrogen wastewater, including: fully reacting the ammonia-nitrogen wastewater to be treated with a first mixture to form a first treatment product, where the first mixture includes iron powder, carbon powder, and ferric oxide; fully reacting the first treatment product with a second mixture to form a second treatment product, where the second mixture includes activated carbon, anthracite, and quartz sand; removing ammonia gas from the second treatment product by air blowing, and the second treatment product is converted into a third treatment product; cooling the third treatment product to room temperature and then discharging it, and converting the removed ammonia gas into ammonia water and then collecting it.

[0005] In some embodiments of this application, before fully reacting the ammonia-nitrogen wastewater to be treated with the first mixture to form a first treatment product, it further includes: heating the ammonia-nitrogen wastewater to be treated to 45 to 55 °C.

[0006] In some embodiments of the present application, before cooling the third treatment product to room temperature, the temperature of the third treatment product is 45 to 55 °C. The method for heating the ammonia nitrogen wastewater to be treated to 45 to 55 °C includes: performing heat exchange between the ammonia nitrogen wastewater to be treated and the third treatment product with a temperature of 45 to 55 °C generated in the previous batch.

[0007] In some embodiments of the present application, before removing ammonia gas from the second treatment product by air stripping, it further includes: adjusting the pH value of the second treatment product to 10.5 to 11.

[0008] In some embodiments of the present application, the method for cooling the third treatment product to room temperature includes: performing heat exchange between the third treatment product and the ammonia nitrogen wastewater to be treated in the next batch.

[0009] In some embodiments of the present application, the method for collecting the removed ammonia gas includes: after cooling the removed ammonia gas to room temperature through heat exchange, introducing the generated ammonia water into an ammonia water storage container, and introducing the cooled ammonia gas into a pure water absorption tower, and the ammonia gas is converted into ammonia water in the pure water absorption tower and then introduced into the ammonia water storage container.

[0010] The embodiments of the present application further provide an ammonia nitrogen wastewater treatment device for performing the ammonia nitrogen wastewater treatment method described in any one of the above. The device includes: a catalytic adsorption device, including a first adsorption pool and a second adsorption pool that can be connected. The first adsorption pool is used as the reaction site for the ammonia nitrogen wastewater to be treated and the first mixture, and the second adsorption pool is used as the reaction site for the first treatment product and the second mixture; a stripping tower for removing ammonia gas from the second treatment product by air stripping to form a third product, and discharging the removed ammonia gas from the top of the stripping tower; a condensation device, the cooling area of the condensation device is connected to the top of the stripping tower for cooling the ammonia gas discharged from the top of the stripping tower to room temperature; an ammonia water storage container, the ammonia water storage container is connected to the cooling area of the condensation device for receiving the ammonia water generated in the condensation device.

[0011] In some embodiments of the present application, the ammonia nitrogen wastewater treatment device further includes a heat exchanger. The heat exchanger is introduced into the ammonia nitrogen wastewater to be treated through a main pipeline and is used to heat the ammonia nitrogen wastewater to be treated by heat exchange. The heat exchanger is connected to the catalytic adsorption device through a first pipeline.

[0012] In some embodiments of the present application, the ammonia nitrogen wastewater treatment device further includes a second adjustment container. The second adjustment container is used to adjust the pH value of the third product discharged from the bottom of the stripping tower to the discharge standard, and introduce the third product with the pH value adjusted to the discharge standard into the heat exchanger to be cooled to room temperature through heat exchange.

[0013] In some embodiments of the present application, the ammonia nitrogen wastewater treatment equipment also includes a sixth pipeline, which connects the main pipeline and the condensing device, and the sixth pipeline is used to pass the ammonia nitrogen wastewater to be treated into the heating zone of the condensing device for heating.

[0014] In some embodiments of the present application, the ammonia nitrogen wastewater treatment equipment also includes a seventh pipeline, which connects the heating zone of the condensing device and the first pipeline, and is used to pass the ammonia nitrogen wastewater to be treated after the temperature is increased in the condensing device into the catalytic adsorption equipment.

[0015] In some embodiments of the present application, the ammonia nitrogen wastewater treatment equipment also includes a first regulating container, which is connected to the second adsorption tank of the catalytic adsorption equipment through a second pipeline, and is connected to the stripping tower through a third pipeline, for adjusting the pH value of the second treatment product to 10.5 to 11.

[0016] In some embodiments of the present application, the ammonia nitrogen wastewater treatment equipment also includes a pure water absorption tower, which is connected to the cooling zone of the condensing device, and is used to receive the ammonia gas cooled in the condensing device, and after the cooled ammonia gas is converted into ammonia water, the ammonia water converted from the cooled ammonia gas is discharged to the ammonia water storage container.

[0017] In some embodiments of the present application, the ammonia nitrogen wastewater treatment equipment also includes an eleventh pipeline, which connects the top of the pure water absorption tower and the bottom of the stripping tower, and is used to pass the ammonia gas that has not been converted into ammonia water in the pure water absorption tower into the stripping tower. A stripping fan is provided on the eleventh pipeline to control the flow direction of the gas in the eleventh pipeline.

[0018] The ammonia nitrogen wastewater treatment method described in the embodiment of the present application utilizes the pollutant hydrogen peroxide contained in the ammonia nitrogen wastewater to be treated to catalytically decompose it to produce hydroxyl free radicals, thereby directly oxidizing and decomposing the organic pollutants in the ammonia nitrogen wastewater to be treated; and further utilizes the flocculation effect of trivalent iron ions produced in the Fenton-like reaction process to capture and remove pollutants such as colloids and suspended particles in the ammonia nitrogen wastewater to be treated; then adjusts the pH value of the second treatment product to further convert the ammonium ions in the solution into ammonia gas, and then produces pure ammonia gas by stripping the second treatment product from which the pollutants have been removed, thereby simultaneously achieving ammonia gas recovery and wastewater discharge that meets the standards.

[0019] Furthermore, the embodiment of the present application realizes the condensation recovery of the removed ammonia gas and the cooling of the third treatment product before discharge and the heating of the ammonia nitrogen wastewater to be treated through a heat exchange process, which also reduces the production cost of the enterprise and reduces pollution to the environment.

[0020] The ammonia nitrogen wastewater treatment method described in the embodiments of the present application can reduce the usage amount of sulfuric acid and the generation amount of ammonium sulfate by about 80%, thus directly and significantly reducing the operation cost of ammonia nitrogen wastewater treatment. Moreover, the industrial-grade ammonia water is recovered in the embodiments of the present application, and the recovered industrial-grade ammonia water can be continuously used for production or sold, generating positive benefits while significantly reducing the operation cost of ammonia nitrogen wastewater treatment. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The following drawings detail the exemplary embodiments disclosed in the present application. Wherein the same reference numerals represent similar structures in several views of the drawings. Those of ordinary skill in the art will understand that these embodiments are non-limiting, exemplary embodiments, and the drawings are only for the purpose of illustration and description, and are not intended to limit the scope of the present application. Embodiments in other ways may also equally achieve the inventive concept in the present application. It should be understood that the drawings are not drawn to scale. Among them:

[0022] Figure 1 is the process flow chart of the ammonia nitrogen wastewater treatment method of the embodiments of the present application;

[0023] Figure 2 is the solubility curve of ammonia gas in aqueous solution;

[0024] Figure 3 is the equipment schematic diagram of the ammonia nitrogen wastewater treatment method of the embodiments of the present application. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0025] The following description provides specific application scenarios and requirements of the present application, aiming to enable those skilled in the art to manufacture and use the content in the present application. For those skilled in the art, various partial modifications to the disclosed embodiments are obvious, and the general principles defined here can be applied to other embodiments and applications without departing from the spirit and scope of the present application. Therefore, the present application is not limited to the shown embodiments, but has the broadest scope consistent with the claims.

[0026] The ammonia nitrogen wastewater generated in the integrated circuit industry has the characteristics of few impurity types, stable wastewater flow and ammonia nitrogen concentration. Although the existing wastewater treatment processes achieve the up-to-standard discharge of the treated wastewater, they do not fully consider the recovery value of ammonia nitrogen. And in the existing processes, the ammonia gas blown off is directly converted into ammonium sulfate waste liquid by adsorption with sulfuric acid, which not only causes waste of ammonia nitrogen resources but also makes the whole process treatment cost relatively high. Based on this, the embodiments of the present application provide an ammonia nitrogen wastewater treatment method that can not only achieve the up-to-standard discharge of ammonia nitrogen wastewater in the electronics industry but also recover the ammonia nitrogen resources in the wastewater.

[0027] The embodiments of the present application provide an ammonia nitrogen wastewater treatment method, as Figure 1 shown, including:

[0028] Step S1: React the ammonia-nitrogen wastewater to be treated fully with a first mixture to form a first treatment product, where the first mixture includes iron powder, carbon powder, and iron tetraoxide;

[0029] Step S2: React the first treatment product fully with a second mixture to form a second treatment product, where the second mixture includes activated carbon, anthracite, and quartz sand;

[0030] Step S3: Remove ammonia gas from the second treatment product by air stripping, and the second treatment product is converted into a third treatment product;

[0031] Step S4: Cool the third treatment product to room temperature and then discharge it, and convert the removed ammonia gas into ammonia water for collection.

[0032] In the embodiments of the present application, before fully reacting the ammonia-nitrogen wastewater to be treated with the first mixture, it may further include heating the ammonia-nitrogen wastewater to be treated to 45°C to 55°C. Optionally, the ammonia-nitrogen wastewater to be treated can be heated to 48°C, 50°C, 53°C, etc. Usually, the initial temperature of the ammonia-nitrogen wastewater to be treated is room temperature, and it can be heated by a water bath or directly heated in the reaction chamber. In an embodiment of the present application, the ammonia-nitrogen wastewater to be treated is heat-exchanged with the third product (i.e., the third treatment product that has not yet cooled to room temperature) in a heat exchanger, which is in a high-temperature state after treating ammonia-nitrogen wastewater in the previous batch, so as to heat the ammonia-nitrogen wastewater to be treated to 45°C to 55°C, and at the same time cool the third product that has not yet cooled to room temperature produced in the previous batch, so as to achieve the purpose of cost saving and improving the thermal energy utilization efficiency. The heat exchanger is, for example, a plate heat exchanger. Among them, the temperature of the third product in a high-temperature state produced after treating ammonia-nitrogen wastewater in the previous batch is 45 to 55°C.

[0033] In the embodiments of the present application, heating the ammonia-nitrogen wastewater to be treated to 45°C to 55°C can also be achieved by introducing the ammonia-nitrogen wastewater at room temperature into a condensation device, so that it undergoes heat exchange with the ammonia gas in a high-temperature state (i.e., the ammonia gas that has not yet cooled to room temperature, and the ammonia gas is the one removed from the stripping tower in the previous batch) produced in the previous batch in the condensation device, so as to heat the ammonia-nitrogen wastewater to be treated to 45°C to 55°C, and at the same time cool the ammonia gas in a high-temperature state produced in the previous batch in the condensation device to room temperature. Among them, the temperature of the ammonia gas removed from the stripping tower is 45 to 55°C.

[0034] As Figure 2 shown, it is the solubility curve of ammonia gas in water. From Figure 2It can be seen that as the temperature increases, the solubility of ammonia in water decreases rapidly. When the temperature rises from room temperature to 50 °C, the solubility of ammonia in water drops rapidly from 52.9 to 23.5. Therefore, in the embodiments of the present application, the ammonia-nitrogen wastewater to be treated is heated to 45 °C to 55 °C to reduce the solubility of ammonia in the ammonia-nitrogen wastewater, so that ammonia is more easily removed in the subsequent process. Further, the process of heating the ammonia-nitrogen wastewater to be treated to 45 °C to 55 °C in the embodiments of the present application does not increase the reaction cost, and at the same time, the ammonia in the high-temperature state generated in the previous batches and the third treatment product that has not dropped to room temperature generated in the previous batches are cooled to room temperature.

[0035] After heating the ammonia-nitrogen wastewater to be treated to 45 °C to 55 °C, step S1 is performed to fully react the ammonia-nitrogen wastewater to be treated with a first mixture to form a first treatment product, and the first mixture includes iron powder, carbon powder, and iron tetraoxide.

[0036] In the embodiments of the present application, the ammonia-nitrogen wastewater to be treated mainly includes dissolved ammonia, as well as pollutants such as hydrogen peroxide, organic pollutants, suspended solids, and colloids. The first mixture at least includes iron powder, carbon powder, and iron trioxide particles. Hydrogen peroxide in the ammonia-nitrogen wastewater to be treated will generate highly oxidizing hydroxyl radicals (HO·) under the catalytic action of iron ions:

[0037] H2O2 + Fe 2+ →Fe 3+ + OH - + HO·; (Equation 1)

[0038] Thereby, the direct oxidation and removal of organic pollutants in the ammonia-nitrogen wastewater to be treated are realized:

[0039] RH + HO· → R· + H2O, (Equation 2)

[0040] wherein, R is a carbon chain structure with a molecular weight less than 10,000;

[0041] In addition, the macromolecular organic pollutants in the ammonia nitrogen wastewater to be treated will be oxidized and broken into chains. The hydrophobic carbonyl groups, ester groups, etc. (organic pollutants) in the ammonia nitrogen wastewater to be treated will be oxidized into hydrophilic carboxyl groups and hydroxyl groups, which is beneficial to the subsequent removal. The trivalent iron ions generated in Formula 1 will cause coagulation reactions with colloids, suspended solids, etc. under the action of double-layer compression and net capture and sweeping, forming flocs. The flocs include silicon dioxide particles, silicon particles, iron ions, aluminum ions, organic substances, a small amount of calcium and magnesium ions, etc. Among them, for micron-scale colloids and suspended solids with a negatively charged core and a positively charged surface, double-layer compression refers to adding an active electrolyte such as iron ions to the colloidal dispersion system. The attraction between the iron ions and the negatively charged ions in the core and the repulsion with the positively charged ions on the surface compress the distance between the two, thereby thinning the diffusion layer on the colloidal surface and making it easier to agglomerate. Net capture and sweeping refers to the phenomenon that a large number of tiny colloidal particles begin to agglomerate, the specific gravity of the flocs will continuously increase, and the small flocs encountered during the sinking of the flocs will also be agglomerated together.

[0042] After the ammonia nitrogen wastewater to be treated reacts fully with the first mixture, a first treatment product is formed. The reaction between the ammonia nitrogen wastewater to be treated and the first mixture can be carried out in any reaction vessel. In one embodiment of the present application, the reaction between the ammonia nitrogen wastewater to be treated and the first mixture is carried out in a catalytic adsorption device, such as a Fenton-like catalytic adsorption tank. The first mixture is placed in the first adsorption tank of the catalytic adsorption device in the form of a filler. The ammonia nitrogen wastewater to be treated at a temperature of 45°C to 55°C flows into the first adsorption tank until the components in the ammonia nitrogen wastewater to be treated react fully with the first mixture to form a first treatment product.

[0043] After the ammonia nitrogen wastewater to be treated reacts fully with the first mixture to form a first treatment product, step S2 is executed: the first treatment product is reacted fully with a second mixture to form a second treatment product. The second mixture includes activated carbon, anthracite, and quartz sand.

[0044] When the first treatment product reacts with the second mixture, the flocs in the first treatment product will collide with each other in the gaps of the second mixture to further flocculate and finally be retained in the second mixture, thereby achieving the removal of pollutants. The residual organic substances in the first treatment product will be adsorbed and removed by the activated carbon in the second mixture.

[0045] Therefore, after the ammonia-nitrogen wastewater to be treated reacts with the first mixture and the second mixture in sequence, the second treatment product formed only includes dissolved ammonia gas and water, and pollutants such as hydrogen peroxide, organic pollutants, suspended solids, and colloids in the ammonia-nitrogen wastewater to be treated are basically removed completely. In the embodiments of the present application, the masses of the first mixture and the second mixture consumed per ton of the ammonia-nitrogen wastewater to be treated are 0.01 - 0.05 kg and 0.1 - 0.3 kg respectively.

[0046] Before performing step S3, it may further include: adjusting the pH value of the second treatment product to 10.5 to 11. In the embodiments of the present application, the method for adjusting the pH value of the second treatment product to 10.5 to 11 is: adding a strong alkaline solution to the second treatment product, so that more ammonium ions in the second treatment product exist in the form of ammonia molecules. Since NH 4+ +OH - =NH3 + H2O, therefore, when the pH value of the second treatment product increases, the amount of OH - increases, and the reaction proceeds to the right, and ammonium ions are converted into ammonia gas.

[0047] Perform step S3, and remove the ammonia gas in the second treatment product by air stripping, and the second treatment product is converted into a third treatment product.

[0048] Since the pollutants in the second treatment product have been removed completely, the ammonia gas removed from the second treatment product is pure ammonia gas. After the ammonia gas is removed from the second treatment product, the ammonia-nitrogen content in the formed third treatment product is lower than 20 ppm, meeting the discharge standard. Further detect the pH value of the third treatment product. If the pH value of the third treatment product does not meet the discharge requirements, add acid to adjust its pH value so that its pH value also meets the discharge requirements, and then it can be discharged after cooling to room temperature.

[0049] Step S4: Discharge the third treatment product after cooling to room temperature, and convert the removed ammonia gas into ammonia water for collection. After steps S1 to S3, the temperature range of the formed third treatment product is 45°C - 55°C, and it can be directly discharged after cooling treatment. In the embodiments of the present application, the process for cooling the third treatment product to room temperature includes: performing heat exchange between the third treatment product and the ammonia-nitrogen wastewater to be treated in the next batch or the next few batches in step S1, so that the temperature of the third treatment product is reduced to room temperature, and the ammonia-nitrogen wastewater to be treated in the next batch or the next few batches is heated to 45°C - 55°C.

[0050] In an embodiment of the present application, the escaped ammonia gas can enter a condensing device and perform heat exchange with the next batch or the next several batches of ammonia nitrogen wastewater to be treated. The water vapor, water mist, etc. in the ammonia gas will be condensed into ammonia water, and the condensed ammonia water will be discharged into an ammonia water storage container for storage. The remaining ammonia gas after cooling passes through a pure water absorption tower, reacts with the water in the pure water absorption tower to form ammonia water, and is also discharged into an ammonia water storage container for storage.

[0051] The ammonia nitrogen wastewater treatment method described in the embodiment of the present application utilizes the pollutant hydrogen peroxide contained in the ammonia nitrogen wastewater to be treated to catalytically decompose it to produce hydroxyl free radicals, thereby directly oxidizing and decomposing the organic pollutants in the ammonia nitrogen wastewater to be treated, without the need to add an oxidant and achieving the removal of two pollutants; and further utilizes the flocculation effect of trivalent iron ions generated in a Fenton-like reaction process to capture and remove pollutants such as colloids and suspended particles in the ammonia nitrogen wastewater to be treated, thereby saving the use of coagulants; then adjusts the pH value of the second treatment product to further convert the ammonium ions in the solution into ammonia gas, and then produces pure ammonia gas by stripping the second treatment product from which the pollutants have been removed, thereby simultaneously achieving ammonia gas recovery and wastewater discharge that meets the standards.

[0052] Furthermore, the embodiment of the present application realizes condensation recovery of the removed ammonia gas and cooling of the third treated product before discharge through a heat exchange process, which also reduces the production cost of the enterprise and reduces pollution to the environment.

[0053] The ammonia nitrogen wastewater treatment method described in the embodiment of the present application can reduce the usage of sulfuric acid and the production of ammonium sulfate by about 80%, thereby directly and significantly reducing the operating cost of ammonia nitrogen wastewater treatment, and also reducing the production of ammonium sulfate waste liquid by 80%. Moreover, the embodiment of the present application not only does not produce ammonium sulfate waste liquid, but also recovers industrial-grade ammonia water, which can continue to be used for production or sale, while significantly reducing the operating cost of ammonia nitrogen wastewater treatment, but also generates positive benefits.

[0054] The present application also provides an ammonia nitrogen wastewater treatment device, see the attached Figure 3 As shown, the device for performing the ammonia nitrogen wastewater treatment method described in the embodiment of the present application includes:

[0055] The embodiment of the present application also provides an ammonia nitrogen wastewater treatment device for performing any of the ammonia nitrogen wastewater treatment methods described above, the device comprising:

[0056] The catalytic adsorption device 102 includes a first adsorption tank A and a second adsorption tank B which are communicable with each other, wherein the first adsorption tank A is used as a reaction site between the ammonia nitrogen wastewater to be treated and the first mixture, and the second adsorption tank B is used as a reaction site between the first treated product and the second mixture;

[0057] A stripping tower 104 is used to strip ammonia in the second treatment product by means of air stripping to form a third product, and discharge the stripped ammonia from the top of the stripping tower 104;

[0058] A condensation device 106, the cooling area of the condensation device 106 is connected to the top of the stripping tower through a fifth pipeline 5, and is used to cool the ammonia discharged from the top of the stripping tower 106 to room temperature;

[0059] An ammonia water storage container 108, the ammonia water storage container 108 is connected to the cooling area of the condensation device through a ninth pipeline 9, and is used to receive the ammonia water generated in the condensation device 106.

[0060] In some embodiments of the present application, the ammonia-nitrogen wastewater treatment equipment further includes a heat exchanger 101, the heat exchanger 101 is connected to the ammonia-nitrogen wastewater to be treated through a main pipeline 13, and is used to heat the ammonia-nitrogen wastewater to be treated by means of heat exchange, and the heat exchanger 101 is connected to the catalytic adsorption device 102 through a first pipeline 1.

[0061] In some embodiments of the present application, the ammonia-nitrogen wastewater treatment equipment further includes a first adjustment container 103, the first adjustment container 103 is connected to the second adsorption tank B of the catalytic adsorption device 102 through a second pipeline 2, and is connected to the stripping tower through a third pipeline 3. The first adjustment container 103 is used to adjust the pH value of the second treatment product to 10.5 to 11.

[0062] In some embodiments of the present application, the ammonia-nitrogen wastewater treatment equipment further includes a second adjustment container 105, the second adjustment container 105 is used to adjust the pH value of the third product discharged from the bottom of the stripping tower 104 to the discharge standard, and the third product with the pH value adjusted to the discharge standard is introduced into the heat exchanger through a fourth pipeline 4 and cooled to room temperature by heat exchange.

[0063] In some embodiments of the present application, the ammonia-nitrogen wastewater treatment equipment further includes a pure water absorption tower 107, the pure water absorption tower 107 is connected to the cooling area of the condensation device 106 through an eighth pipeline 8, and is used to receive the cooled ammonia in the condensation device 106, and after the cooled ammonia is converted into ammonia water, the ammonia water converted from the cooled ammonia is discharged to the ammonia water storage container 108 through a ninth pipeline 9.

[0064] In some embodiments of the present application, the ammonia-nitrogen wastewater treatment equipment further includes a sixth pipeline 6, the sixth pipeline 6 connects the main pipeline and the condensation device 106, and the sixth pipeline 6 is used to introduce the ammonia-nitrogen wastewater to be treated introduced into the main pipeline 13 into the heating area of the condensation device 106 for heating.

[0065] In some embodiments of the present application, the ammonia nitrogen wastewater treatment equipment further includes a seventh pipeline 7, and the seventh pipeline 7 communicates with the heating zone of the condensation device 106 and the first pipeline 1, and is used to introduce the ammonia nitrogen wastewater to be treated after the temperature is raised in the condensation device 106 into the catalytic adsorption device 102.

[0066] In some embodiments of the present application, the ammonia nitrogen wastewater treatment equipment further includes an eleventh pipeline 11, and the eleventh pipeline 11 connects the top of the pure water absorption tower and the bottom of the stripping tower, and is used to introduce the ammonia gas that has not been converted into ammonia water in the pure water absorption tower 107 into the stripping tower 104. A stripping fan 109 is arranged on the eleventh pipeline 11 to control the flow direction of the gas in the eleventh pipeline 11.

[0067] During application, the ammonia nitrogen wastewater to be treated is introduced into the heat exchanger 101 through the main pipeline 13 for heating through a heat exchange method, and then is introduced into the catalytic adsorption device 102 from the heat exchanger 101 through the first pipeline 1; or the ammonia nitrogen wastewater to be treated is introduced into the condensation device 106 through the sixth pipeline 6 for heating through a heat exchange method and then is transported to the first pipeline 1 through the seventh pipeline 7, and is introduced into the catalytic adsorption device 102 from the heat exchanger 101 through the first pipeline 1.

[0068] In the catalytic adsorption device 102, the first mixture is placed in the first adsorption tank A, the second mixture is placed in the second adsorption tank B, and the ammonia nitrogen wastewater to be treated is sequentially introduced into the first adsorption tank A and the second adsorption tank B, and fully reacts with the first mixture in the first adsorption tank A to form a first treatment product, and the first treatment product is introduced into the second adsorption tank B and fully reacts with the second mixture in the second adsorption tank B to form a second treatment product.

[0069] The second treatment product is introduced into the first regulating container 103 through the second pipeline 2. An alkaline reagent such as sodium hydroxide is added in the first regulating container 103 to adjust the pH of the second treatment product to 10.5 to 11, and then it is introduced into the stripping tower 104 through the third pipeline 3. Ammonia gas is stripped from the second treatment product in the stripping tower 104. Among them, the ammonia gas stripped from the stripping tower 104 enters the condensation device 106 through the fifth pipeline 5 after being discharged from the top of the stripping tower. After condensation, part of the ammonia gas is converted into ammonia water, which is directly introduced into the ammonia water storage container 108 through the ninth pipeline 9 for storage; part of the ammonia gas that still does not dissolve in water after passing through the condensation device 106 is introduced into the pure water absorption tower 107 through the eighth pipeline 8, dissolves in water in the pure water absorption tower 107 to be converted into ammonia water, and enters the ammonia water storage container 108 through the tenth pipeline 10 for storage; part of the ammonia gas that still does not dissolve in water in the pure water absorption tower 107 is introduced into the stripping tower 104 again through the eleventh pipeline 11, and is discharged from the top of the stripping tower 104 and enters the condensation device 106 again. Among them, a stripping fan 109 is provided on the eleventh pipeline 11 to control the flow rate and flow direction of the ammonia gas in the eleventh pipeline 11. The closed-loop design of the pipeline and equipment avoids gas pollution to the environment during the reaction process.

[0070] The third treatment product generated in the stripping tower 104 is introduced into the second regulating container 105 through the twelfth pipeline 12 from the bottom of the stripping tower 104. After the pH value is adjusted to the discharge standard in the second regulating container 105, it is introduced into the heat exchanger 101 through the fourth pipeline 4 for temperature reduction treatment, and is directly discharged from the heat exchanger 101 after being reduced to normal temperature.

[0071] When the equipment described in this application is in use, the untreated ammonia nitrogen wastewater that is not heated can be heated through two paths. Path 1: The untreated ammonia nitrogen wastewater in the main pipeline 13 enters the condensation device 106 through the sixth pipeline, completes heat exchange with the high-temperature gas (such as ammonia gas stripped from the stripping tower) introduced into the condensation device 106, and after being heated to the set temperature, the heated untreated ammonia nitrogen wastewater in the condensation device 106 is introduced into the catalytic adsorption equipment through the seventh pipeline 7. Path 2: The untreated ammonia nitrogen wastewater in the main pipeline 13 is directly introduced into the heat exchanger 101, where it exchanges heat with the high-temperature third treatment product discharged from the stripping tower 104 (or discharged after the pH value is adjusted in the second regulating container). After the untreated ammonia nitrogen wastewater is heated to the set temperature, it is introduced into the catalytic adsorption equipment 102 through the first pipeline 1. At the same time, the third treatment product whose temperature has dropped to normal temperature after heat exchange is directly discharged from the heat exchanger 101.

[0072] In summary, after reading the content of this application, those skilled in the art will understand that the foregoing application content may be presented only by way of example and may not be restrictive. Although not explicitly stated herein, those skilled in the art can understand that this application is intended to encompass various reasonable changes, improvements, and modifications to the embodiments. These changes, improvements, and modifications are all within the spirit and scope of the exemplary embodiments of this application.

[0073] It should be understood that the term "and / or" used in this embodiment includes any or all combinations of one or more of the associated listed items. It should be understood that when an element is referred to as being "connected" or "coupled" to another element, it can be directly connected or coupled to the other element, or there may also be intermediate elements.

[0074] Similarly, it should be understood that when an element such as a layer, region, or substrate is referred to as being "on" another element, it can be directly on the other element, or there may also be intermediate elements. In contrast, the term "directly" means without intermediate elements. It should also be understood that the terms "comprise", "comprising", "include", or "including", when used in this application document, specify the presence of the recited features, wholes, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, wholes, steps, operations, elements, components, and / or groups thereof.

[0075] It should also be understood that although the terms first, second, third, etc. may be used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another. Thus, without departing from the teachings of this application, a first element in some embodiments may be referred to as a second element in other embodiments. The same reference numerals or the same reference identifiers represent the same elements throughout the specification.

[0076] In addition, the specification of this application describes the exemplary embodiments by referring to idealized exemplary cross-sectional views and / or plan views and / or three-dimensional views. Therefore, differences from the illustrated shapes due to, for example, manufacturing techniques and / or tolerances are foreseeable. Therefore, the exemplary embodiments should not be construed as being limited to the shapes of the regions shown herein, but should include deviations in the shapes caused by, for example, manufacturing. For example, an etched region shown as rectangular will typically have rounded or curved features. Therefore, the regions shown in the figures are substantially schematic, and their shapes are not intended to show the actual shape of the regions of the device nor to limit the scope of the exemplary embodiments.

Claims

1. A method for treating ammonia nitrogen wastewater, characterized in that Including: Fully reacting the ammonia-nitrogen wastewater to be treated with a first mixture to form a first treatment product, the first mixture including iron powder, carbon powder, and iron tetraoxide; Fully reacting the first treatment product with a second mixture to form a second treatment product, the second mixture including activated carbon, anthracite, and quartz sand; Removing ammonia gas from the second treatment product by air stripping, and the second treatment product is converted into a third treatment product; Cooling the third treatment product to room temperature and then discharging it, and converting the removed ammonia gas into ammonia water for collection.

2. The ammonia nitrogen wastewater treatment method according to claim 1, characterized in that, Before fully reacting the ammonia-nitrogen wastewater to be treated with the first mixture to form a first treatment product, it further includes: heating the ammonia-nitrogen wastewater to be treated to 45 to 55 °C.

3. The ammonia nitrogen wastewater treatment method according to claim 2, characterized in that, Before cooling the third treatment product to room temperature, the temperature of the third treatment product is 45 to 55 °C. The method of heating the ammonia-nitrogen wastewater to be treated to 45 to 55 °C includes: performing heat exchange between the ammonia-nitrogen wastewater to be treated and the third treatment product with a temperature of 45 to 55 °C generated in the previous batch.

4. The ammonia nitrogen wastewater treatment method according to claim 1, characterized in that, Before removing ammonia gas from the second treatment product by air stripping, it further includes: adjusting the pH value of the second treatment product to 10.5 to 11.

5. The ammonia nitrogen wastewater treatment method according to claim 1, characterized in that, The method of cooling the third treatment product to room temperature includes: performing heat exchange between the third treatment product and the ammonia-nitrogen wastewater to be treated in the next batch.

6. The ammonia nitrogen wastewater treatment method according to claim 1, characterized in that, The method of collecting the removed ammonia gas includes: cooling the removed ammonia gas to room temperature by heat exchange, then introducing the generated ammonia water after cooling into an ammonia water storage container, and introducing the cooled ammonia gas into a pure water absorption tower, and the ammonia gas is converted into ammonia water in the pure water absorption tower and then introduced into the ammonia water storage container.

7. An ammonia-nitrogen wastewater treatment device for implementing the ammonia-nitrogen wastewater treatment method according to any one of claims 1 to 6, the device including: A catalytic adsorption device, including a first adsorption pool and a second adsorption pool that can be connected. The first adsorption pool is used as the reaction site for the ammonia-nitrogen wastewater to be treated and the first mixture, and the second adsorption pool is used as the reaction site for the first treatment product and the second mixture; A stripping tower for removing ammonia gas from the second treatment product by air stripping to form a third product, and discharging the removed ammonia gas from the top of the stripping tower; A condensation device, the cooling area of the condensation device is connected to the top of the stripping tower, and is used to cool the ammonia gas discharged from the top of the stripping tower to room temperature; An ammonia water storage container, the ammonia water storage container is connected to the cooling area of the condensation device, and is used to receive the ammonia water generated in the condensation device.

8. The ammonia nitrogen wastewater treatment equipment according to claim 7, characterized in that, It further includes a heat exchanger, the heat exchanger is introduced into the ammonia-nitrogen wastewater to be treated through a main pipeline, and is used to heat the ammonia-nitrogen wastewater to be treated by heat exchange. The heat exchanger is connected to the catalytic adsorption device through a first pipeline.

9. The ammonia nitrogen wastewater treatment equipment according to claim 8, wherein, It further includes a second adjustment container, the second adjustment container is used to adjust the pH value of the third product discharged from the bottom of the stripping tower to the discharge standard, and introduce the third product with the pH value adjusted to the discharge standard into the heat exchanger to be cooled to room temperature by heat exchange.

10. The ammonia nitrogen wastewater treatment equipment according to claim 8, characterized in that, It further includes a sixth pipeline, which connects the main pipeline and the condensation device, and the sixth pipeline is used to introduce the ammonia nitrogen wastewater to be treated into the heating zone of the condensation device for heating.

11. The ammonia nitrogen wastewater treatment equipment according to claim 10, characterized in that, It further includes a seventh pipeline, which communicates the heating zone of the condensation device and the first pipeline, and is used to introduce the ammonia nitrogen wastewater to be treated after temperature rise in the condensation device into the catalytic adsorption equipment.

12. The ammonia nitrogen wastewater treatment equipment according to claim 7, wherein, It further includes a first adjustment container, which is communicated with the second adsorption tank of the catalytic adsorption equipment through a second pipeline and is communicated with the stripping tower through a third pipeline, and is used to adjust the pH value of the second treatment product to 10.5 to 11.

13. The ammonia nitrogen wastewater treatment equipment according to claim 7, characterized in that, It further includes a pure water absorption tower, which communicates with the cooling zone of the condensation device, and is used to receive the cooled ammonia gas in the condensation device, and after the cooled ammonia gas is converted into ammonia water, discharge the ammonia water converted from the cooled ammonia gas to the ammonia water storage container.

14. The ammonia nitrogen wastewater treatment equipment according to claim 13, characterized in that, It further includes an eleventh pipeline, which connects the top of the pure water absorption tower and the bottom of the stripping tower, and is used to introduce the ammonia gas that has not been converted into ammonia water in the pure water absorption tower into the stripping tower, and a stripping fan is arranged on the eleventh pipeline to control the flow direction of the gas in the eleventh pipeline.

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