Wastewater denitrification process system

Abstract

The utility model belongs to the technical field of air environment monitoring devices, and particularly relates to a wastewater denitrification process system and a pretreatment process system, the pretreatment process system comprises an ultrafiltration membrane water inlet tank, an ultrafiltration membrane water inlet pump, an ultrafiltration membrane separator, an ultrafiltration membrane water producing tank, an ultrafiltration membrane backwashing water pump and an air compressor; a water outlet of the ultrafiltration membrane water inlet tank is connected to a water inlet of the ultrafiltration membrane water inlet pump through a pipeline, a water outlet of the ultrafiltration membrane water inlet pump is connected with a water inlet of the ultrafiltration membrane separator, and a water outlet of the ultrafiltration membrane separator is connected with a water inlet of the ultrafiltration membrane water production tank through a post-filtration pipeline; according to the wastewater denitrification process system disclosed by the utility model, ammonia nitrogen is removed by utilizing the selective permeability of the membrane, the operation is convenient, the ammonia nitrogen recovery rate is high, and secondary pollution is avoided. According to the utility model, the concentration of ammonia nitrogen in the wastewater is effectively reduced, the wastewater can be discharged after reaching the standard, and a water inlet guarantee can be provided for subsequent treatment, especially biological treatment.

Description

Technical Field

[0001] The utility model relates to the technical field of sewage treatment, in particular to a wastewater denitrification process system. Background Art

[0002] Ammonia nitrogen wastewater mainly comes from fertilizers, coking, petrochemicals, pharmaceuticals, food, landfills, etc. A large amount of ammonia nitrogen wastewater discharged into water bodies not only causes eutrophication of water bodies and causes black and smelly water bodies, but also increases the difficulty and cost of water treatment, and even has toxic effects on people and organisms. The treatment processes for ammonia nitrogen wastewater include various treatment processes such as biological methods and physicochemical methods.

[0003] Common physical and chemical methods include:

[0004] 1. Blow-off method

[0005] A method of separation under alkaline conditions using the gas-liquid equilibrium relationship between the gas phase concentration and the liquid phase concentration of ammonia nitrogen. It is generally believed that stripping is related to temperature, pH, and gas-liquid ratio.

[0006] 2. Zeolite deamination method

[0007] Utilize the cations in zeolite to react with NH4 in wastewater + Exchange is performed to achieve the purpose of denitrification. The application of zeolite deamination method must consider the regeneration of zeolite, which usually includes regeneration liquid method and incineration method. When using the incineration method, the ammonia gas produced must be treated. This method is suitable for the treatment of low-concentration ammonia nitrogen wastewater, and the ammonia nitrogen content should be 10-20 mg / L.

[0008] 3. MAP precipitation method

[0009] Mainly using the following chemical reactions: Mg 2+ +NH4 + +PO4 3- =MgNH4PO4

[0010] Theoretically, adding phosphate and magnesium salts to wastewater containing high concentrations of ammonia nitrogen in a certain proportion will result in [Mg 2+ ]NH4 + ][PO4 3- ]>2.5×10 –13 Magnesium ammonium phosphate (MAP) can be generated to remove ammonia nitrogen from wastewater.

[0011] 4. Chemical oxidation method

[0012] A method of removing ammonia nitrogen by directly oxidizing it into nitrogen gas using a strong oxidant. Breakpoint chlorination is to remove ammonia by reacting ammonia in water with chlorine to generate ammonia gas. This method can also have a bactericidal effect, but the residual chlorine produced will have an impact on fish, so residual chlorine removal facilities must be installed.

[0013] Among the above methods, zeolite deamination and chemical oxidation are suitable for treating low-concentration ammonia nitrogen wastewater. However, the stripping technology for removing ammonia requires a large amount of air, so it has the characteristics of high power consumption, easy scaling of the stripping tower, easy secondary pollution, and difficult to meet the requirements of effluent. Utility Model Content

[0014] The utility model aims to solve the shortcomings of the prior art that the environmental monitoring device for polluted sites is inconvenient to adjust the height during actual use and cannot adapt to a variety of use environments, and proposes a wastewater denitrification process system.

[0015] In order to achieve the above purpose, the utility model adopts the following technical solutions:

[0016] A wastewater denitrification process system, comprising:

[0017] A pretreatment process system, the pretreatment process system comprising an ultrafiltration membrane water inlet tank, an ultrafiltration membrane water inlet pump, an ultrafiltration membrane separator, an ultrafiltration membrane water production tank, an ultrafiltration membrane backwash water pump and an air compressor;

[0018] The water outlet of the ultrafiltration membrane water inlet tank is connected to the water inlet of the ultrafiltration membrane water inlet pump through a pipeline, the water outlet of the ultrafiltration membrane water inlet pump is connected to the water inlet of the ultrafiltration membrane separator, and the water outlet of the ultrafiltration membrane separator is connected to the water inlet of the ultrafiltration membrane water production tank through a post-filtration pipeline;

[0019] The ultrafiltration membrane water production tank is provided with a first water production tank outlet and a second water production tank outlet, the first water outlet of the ultrafiltration membrane water production tank is connected to the ultrafiltration membrane water production trunk pipeline, the ultrafiltration membrane water production trunk pipeline is connected to the water inlet of the ultrafiltration membrane water production branch pipeline, the ultrafiltration membrane backwash water pump is arranged on the ultrafiltration membrane water production branch pipeline, and the water outlet of the ultrafiltration membrane water production branch pipeline is connected to the post-filtration pipeline.

[0020] Furthermore, it also includes a deamination process system, which includes a deamination membrane water inlet pump, a deamination membrane separator, a dilute sulfuric acid circulation box and a dilute sulfuric acid circulation pump;

[0021] The deamination membrane separator is provided with a first deamination membrane water inlet, a second deamination membrane water inlet, a first deamination membrane water outlet and a second deamination membrane water outlet.

[0022] The water outlet of the second water production tank of the ultrafiltration membrane water production tank is connected to the water inlet of the deamination membrane water inlet pump, the water outlet of the deamination membrane water inlet pump is connected to the first deamination membrane water inlet of the deamination membrane separator, the water outlet of the dilute sulfuric acid circulation box is connected to the water inlet of the dilute sulfuric acid circulation pump, and the water outlet of the dilute sulfuric acid circulation pump is connected to the second deamination membrane water inlet of the deamination membrane separator;

[0023] The first deamination membrane water outlet of the deamination membrane separator is connected to the deamination water production pipeline, and the second deamination membrane water outlet of the deamination membrane separator is connected to the water inlet of the dilute sulfuric acid circulation box.

[0024] Furthermore, the bottom of the ultrafiltration membrane separator is connected to a drainage pool via a drainage pipe.

[0025] Furthermore, the air compressor is provided with an air storage tank.

[0026] Furthermore, the incoming water is connected to the ultrafiltration membrane water inlet tank through a pipeline, and the ultrafiltration membrane water production trunk pipeline produces ultrafiltration membrane produced water to the outside.

[0027] Furthermore, the deammoniation water production pipeline produces deammoniation water externally.

[0028] Beneficial effects:

[0029] 1. A wastewater denitrification process system that uses the selective permeability of the membrane to remove ammonia nitrogen. It is easy to operate, has a high ammonia nitrogen recovery rate, and has no secondary pollution;

[0030] 2. Free ammonia gas evaporates from the wastewater, diffuses through the membrane pores, and chemically reacts with sulfuric acid at the interface of the sulfuric acid membrane pores, thereby removing the ammonia gas;

[0031] In the utility model, the concentration of ammonia nitrogen in wastewater is effectively reduced, so that the discharge can meet the standard, and water inlet guarantee can be provided for subsequent treatment, especially biological treatment. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 This is a schematic diagram of the structure of the pretreatment process system of the utility model;

[0033] Figure 2 This is a schematic diagram of the structure of the deammoniation process system of the utility model.

[0034] In the figure: 1. Ultrafiltration membrane water inlet tank; 2. Ultrafiltration membrane water inlet pump; 3. Ultrafiltration membrane separator; 4. Ultrafiltration membrane water production tank; 5. Ultrafiltration membrane backwash water pump; 6. Air compressor; 7. Deamination membrane water inlet pump; 8. Deamination membrane separator; 9. Dilute sulfuric acid circulation box; 10. Dilute sulfuric acid circulation pump; 11. Pretreatment process system; 12. Deamination process system; 13. Ultrafiltration membrane water production trunk pipeline; 14. Ultrafiltration membrane water production branch pipeline; 15. Post-filtration pipeline; 16. Deamination water production pipeline. DETAILED DESCRIPTION

[0035] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments.

[0036] Example

[0037] Reference Figure 1 and Figure 2 , a wastewater denitrification process system, comprising:

[0038] A pretreatment process system 11, wherein the pretreatment process system 11 comprises an ultrafiltration membrane water inlet tank 1, an ultrafiltration membrane water inlet pump 2, an ultrafiltration membrane separator 3, an ultrafiltration membrane water production tank 4, an ultrafiltration membrane backwash water pump 5 and an air compressor 6;

[0039] The water outlet of the ultrafiltration membrane water inlet tank 1 is connected to the water inlet of the ultrafiltration membrane water inlet pump 2 through a pipeline, the water outlet of the ultrafiltration membrane water inlet pump 2 is connected to the water inlet of the ultrafiltration membrane separator 3, and the water outlet of the ultrafiltration membrane separator 3 is connected to the water inlet of the ultrafiltration membrane water production tank 4 through a post-filtration pipeline 15;

[0040] The ultrafiltration membrane water production tank 4 is provided with a first water production tank outlet and a second water production tank outlet. The first water outlet of the ultrafiltration membrane water production tank 4 is connected to the ultrafiltration membrane water production trunk pipeline 13. The ultrafiltration membrane water production trunk pipeline 13 is connected to the water inlet of the ultrafiltration membrane water production branch pipeline 14. The ultrafiltration membrane backwash water pump 5 is arranged on the ultrafiltration membrane water production branch pipeline 14. The water outlet of the ultrafiltration membrane water production branch pipeline 14 is connected to the post-filtration pipeline 15.

[0041] Furthermore, it also includes a deamination process system 12, wherein the deamination process system 12 includes a deamination membrane water inlet pump 7, a deamination membrane separator 8, a dilute sulfuric acid circulation box 9 and a dilute sulfuric acid circulation pump 10;

[0042] The deamination membrane separator 8 is provided with a first deamination membrane water inlet, a second deamination membrane water inlet, a first deamination membrane water outlet and a second deamination membrane water outlet.

[0043] The second water production tank water outlet of the ultrafiltration membrane water production tank 4 is connected to the water inlet of the deamination membrane water inlet pump 7, the water outlet of the deamination membrane water inlet pump 7 is connected to the first deamination membrane water inlet of the deamination membrane separator 8, the water outlet of the dilute sulfuric acid circulation box 9 is connected to the water inlet of the dilute sulfuric acid circulation pump 10, and the water outlet of the dilute sulfuric acid circulation pump 10 is connected to the second deamination membrane water inlet of the deamination membrane separator 8;

[0044] The first deamination membrane water outlet of the deamination membrane separator 8 is connected to the deamination water production pipeline 16 , and the second deamination membrane water outlet of the deamination membrane separator 8 is connected to the water inlet of the dilute sulfuric acid circulation box 9 .

[0045] Furthermore, the bottom of the ultrafiltration membrane separator 3 is connected to a drainage pool via a drainage pipe.

[0046] Furthermore, the air compressor 6 is provided with an air storage tank.

[0047] Furthermore, the incoming water is connected to the ultrafiltration membrane water inlet tank 1 through a pipeline, and the ultrafiltration membrane water production trunk pipeline 13 produces ultrafiltration membrane water production to the outside.

[0048] Furthermore, the deammoniation water production pipeline 16 produces deammoniation water to the outside.

[0049] The working principle of the utility model: a wastewater denitrification process system that utilizes the selective permeability of the membrane to remove ammonia nitrogen, which is easy to operate, has a high ammonia nitrogen recovery rate, and has no secondary pollution. The gas-water separation membrane removes ammonia nitrogen. Ammonia nitrogen exists in a dissociation equilibrium in water. As the pH increases, the proportion of ammonia in the NH3 form in water increases. At a certain temperature and pressure, the gaseous and liquid states of NH3 reach equilibrium. According to the principle of chemical equilibrium movement, chemical equilibrium can only be maintained under certain conditions. "If one of the conditions of the equilibrium system is changed, such as concentration, pressure or temperature, the equilibrium will move in a direction that can weaken this change." In accordance with this principle, the following design concept was carried out: on one side of the membrane is high-concentration ammonia nitrogen wastewater, and on the other side is an acidic aqueous solution or water. At a certain temperature and pressure, the free ammonia NH in the wastewater 4+ , it turns into ammonia molecules NH3, and diffuses to the membrane surface through the interface of the raw liquid side. Under the action of the partial pressure difference on the membrane surface, it passes through the membrane pores and enters the absorption liquid, and quickly reacts with H in the acidic solution. + The reaction generates ammonium salt.

[0050] Before the raw water enters the gas membrane denitrification, the turbidity in the wastewater needs to be reduced. The macromolecular substances and particles in the wastewater are removed by using the mechanical screening effect of the membrane surface aperture, the blocking and retardation of the membrane pores, and the adsorption of impurities by the membrane surface and the membrane pores. Under the action of external force, the separated solution flows along the surface of the ultrafiltration membrane at a certain flow rate. The solvent, low molecular weight substances, and inorganic ions in the solution pass through the ultrafiltration membrane from the high-pressure side into the low-pressure side and are discharged as filtrate; while the macromolecular substances, colloidal particles, and microorganisms in the solution are retained by the ultrafiltration membrane, and the solution is concentrated and discharged in the form of concentrated liquid.

[0051] After pretreatment, the pH value of the wastewater is adjusted to dissociate the ammonium in the ammonia nitrogen wastewater into free ammonia;

[0052] The dissociated ammonia nitrogen wastewater is pumped into the gas separation membrane and passed into the tube side of the membrane contactor, and the absorbent sulfuric acid is passed into the shell side of the membrane contactor. The hydrophobic porous membrane made of PTFE separates the wastewater and sulfuric acid, and the surface membrane pores provide a contact absorption and mass transfer interface;

[0053] The free ammonia gas evaporates from the wastewater, diffuses through the membrane pores, and comes into contact with sulfuric acid at the interface of the sulfuric acid membrane pores to produce a chemical reaction, thereby removing the ammonia gas.

[0054] The utility model effectively reduces the concentration of ammonia nitrogen in wastewater, so that the discharge can meet the standard, and also provides water inlet guarantee for subsequent treatment, especially biological treatment.

[0055] The ultrafiltration membrane is an artificial permeable membrane used in the ultrafiltration process. It is made of polymer materials such as cellulose acetate, cellulose acetate ester, polyethylene, polysulfone and polyamide. Generally, it is pre-made into various types of membrane components such as tubular, plate, roll, capillary, etc., and then multiple components are assembled together for use to increase the filtration area and facilitate maintenance.

[0056] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes within the technical scope disclosed by the present invention according to the technical scheme and the utility model concept of the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A wastewater denitrification process system, characterized in that: include: A pretreatment process system (11), the pretreatment process system (11) comprising an ultrafiltration membrane water inlet tank (1), an ultrafiltration membrane water inlet pump (2), an ultrafiltration membrane separator (3), an ultrafiltration membrane water production tank (4), an ultrafiltration membrane backwash water pump (5) and an air compressor (6); The water outlet of the ultrafiltration membrane water inlet tank (1) is connected to the water inlet of the ultrafiltration membrane water inlet pump (2) through a pipeline, the water outlet of the ultrafiltration membrane water inlet pump (2) is connected to the water inlet of the ultrafiltration membrane separator (3), and the water outlet of the ultrafiltration membrane separator (3) is connected to the water inlet of the ultrafiltration membrane water production tank (4) through a post-filtration pipeline (15); The ultrafiltration membrane water production tank (4) is provided with a first water production tank outlet and a second water production tank outlet. The first water outlet of the ultrafiltration membrane water production tank (4) is connected to the ultrafiltration membrane water production trunk pipeline (13). The ultrafiltration membrane water production trunk pipeline (13) is connected to the water inlet of the ultrafiltration membrane water production branch pipeline (14). The ultrafiltration membrane backwash water pump (5) is provided on the ultrafiltration membrane water production branch pipeline (14). The water outlet of the ultrafiltration membrane water production branch pipeline (14) is connected to the post-filtration pipeline (15).

2. A wastewater denitrification process system according to claim 1, characterized in that: The invention also comprises a deamination process system (12), wherein the deamination process system (12) comprises a deamination membrane water inlet pump (7), a deamination membrane separator (8), a dilute sulfuric acid circulation box (9) and a dilute sulfuric acid circulation pump (10); The deamination membrane separator (8) is provided with a first deamination membrane water inlet, a second deamination membrane water inlet, a first deamination membrane water outlet and a second deamination membrane water outlet. The second water production tank water outlet of the ultrafiltration membrane water production tank (4) is connected to the water inlet of the deamination membrane water inlet pump (7), the water outlet of the deamination membrane water inlet pump (7) is connected to the first deamination membrane water inlet of the deamination membrane separator (8), the water outlet of the dilute sulfuric acid circulation box (9) is connected to the water inlet of the dilute sulfuric acid circulation pump (10), and the water outlet of the dilute sulfuric acid circulation pump (10) is connected to the second deamination membrane water inlet of the deamination membrane separator (8); The first deamination membrane water outlet of the deamination membrane separator (8) is connected to the deamination water production pipeline (16), and the second deamination membrane water outlet of the deamination membrane separator (8) is connected to the water inlet of the dilute sulfuric acid circulation box (9).

3. A wastewater denitrification process system according to claim 1, characterized in that: The air compressor (6) is provided with an air storage tank.

4. A wastewater denitrification process system according to claim 1, characterized in that: Incoming water is connected to the ultrafiltration membrane water inlet tank (1) through a pipeline, and the ultrafiltration membrane water production trunk pipeline (13) produces ultrafiltration membrane produced water outward.

5. A wastewater denitrification process system according to claim 2, characterized in that: The deammoniation water production pipeline (16) produces deammoniation water to the outside.

Images