Synchronous denitration ammonia recovery device

Abstract

The utility model provides a synchronous denitration ammonia recovery device which comprises a to-be-treated water sample container, a denitration module and an ammonia nitrogen recovery module, ammonia nitrogen generated by reaction of the denitration module is recovered in the ammonia nitrogen recovery module, and the denitration module is an electrolytic cell; the ammonia nitrogen recovery module comprises a gas separation chamber and a trapping chamber, a hydrophobic gas-permeable membrane is arranged between the gas separation chamber and the trapping chamber, and the trapping chamber is communicated with the atmosphere through an acid solution container; the to-be-treated water sample container is communicated with a cathode chamber of the electrolytic cell so as to convey a to-be-treated water sample to the cathode chamber for reaction, the cathode chamber of the electrolytic cell is communicated with the gas separation chamber so as to convey the water sample after reduction reaction, and the gas separation chamber is communicated with the anode chamber so as to convey the water sample after gas separation; the anode chamber is communicated with the to-be-treated water sample container so as to transmit the unreacted water sample to the cathode chamber for circulating electrolysis; the acid solution container is communicated with the trapping chamber so as to convey an acid solution to the trapping chamber to react with ammonia nitrogen.

Description

Technical Field

[0001] The utility model relates to the field of water treatment, in particular to an ammonia recovery device for synchronous denitration. Background Art

[0002] As the main body of nitrogen cycle, nitrogen in water is an important component of global biogeochemical cycle. Nitrogen mainly exists in the form of nitrate nitrogen, nitrite nitrogen, ammonia nitrogen, etc. Nitrate is the most stable nitrogen compound in aerobic environment and is difficult to transform through natural pathways. This makes nitrate a common pollutant in water. High concentration of nitrate wastewater is generated in the production of coking, electroplating, fertilizer, explosives industry, etc. The release of large amounts of ammonia nitrogen will not only have a huge impact on the ecological environment, but also increase greenhouse gas emissions.

[0003] Recycling ammonia nitrogen and making use of it as a resource can not only reduce environmental threats, but also produce nitrogen fertilizer products. As a basic tool, the ammonia nitrogen recovery device can recycle ammonia nitrogen from industrial wastewater, aquaculture tail water and sewage treatment plants, thus realizing resource utilization.

[0004] In order to facilitate the recovery of ammonia nitrogen, devices for simultaneous denitrification and ammonia recovery have emerged, and most of these devices use chemical methods, biological methods, or physical and chemical methods. The disadvantages of chemical methods are high costs and pollution; the disadvantages of biological methods are slow reaction speed and some method conditions have not been fully determined; the disadvantages of physical and chemical methods are harsh conditions and high energy consumption.

[0005] Therefore, a new device capable of simultaneous denitrification and ammonia recovery is needed to overcome the above-mentioned shortcomings. Utility Model Content

[0006] The technical problem to be solved by the utility model is to provide an ammonia recovery device for synchronous denitration, which can simultaneously perform denitration reaction and ammonia nitrogen recovery and has low cost, low pollution, fast reaction and low energy consumption.

[0007] In order to solve the above technical problems, the utility model provides an ammonia recovery device for synchronous denitration, comprising a water sample container to be processed, a denitration module, and an ammonia nitrogen recovery module. The ammonia nitrogen generated by the reaction of the denitration module is recovered in the ammonia nitrogen recovery module, and the denitration module is an electrolytic cell; the ammonia nitrogen recovery module comprises a gas separation chamber and a capture chamber, a hydrophobic breathable membrane is arranged between the gas separation chamber and the capture chamber, and the capture chamber is connected to the atmosphere through an acid solution container;

[0008] The water sample container to be processed is connected to the cathode chamber of the electrolytic cell to transport the water sample to be processed to the cathode chamber for reaction, the cathode chamber of the electrolytic cell is connected to the gas separation chamber to transmit the water sample after the reduction reaction, the gas separation chamber is connected to the anode chamber to transmit the water sample after gas separation, and the anode chamber is connected to the water sample container to be processed to transmit the unreacted water sample to the cathode chamber for cyclic electrolysis;

[0009] The acid solution container is communicated with the capture chamber to transport the acid solution to the capture chamber to react with ammonia nitrogen.

[0010] In some embodiments, the cathode chamber and the anode chamber are separated by a proton exchange membrane; the anode chamber is provided with an anode electrode connected to the positive pole of the power supply, and the cathode chamber is provided with a cathode electrode connected to the negative pole of the power supply.

[0011] In some embodiments, the water sample container to be processed is provided with a first water pipe and a second water pipe, the first water pipe is connected to the cathode chamber through a first fluid conveying device, the second water pipe is connected to the anode chamber, and the height of the second water pipe mouth in the anode chamber is higher than the height in the water sample container to be processed.

[0012] In some embodiments, the cathode chamber is connected to the gas separation chamber through a third water pipe, and the height of the third water pipe mouth in the cathode chamber is higher than that in the gas separation chamber; the gas separation chamber is connected to the anode chamber through a fourth water pipe, and the height of the fourth water pipe mouth in the gas separation chamber is higher than that in the anode chamber.

[0013] In some embodiments, the acidic solution container includes a fifth water pipe and a sixth water pipe, the fifth water pipe is connected to the capture chamber via a second fluid delivery device, the sixth water pipe is communicated with the capture chamber, and the height of the sixth water pipe mouth in the capture chamber is higher than that in the ammonia reaction container.

[0014] In some embodiments, the acidic solution container is provided with an air duct connected to the atmosphere.

[0015] In some embodiments, a stirring component is provided in the gas separation chamber.

[0016] In some embodiments, the acidic solution is concentrated sulfuric acid.

[0017] In some of the embodiments, the hydrophobic breathable membrane has a pore size ranging from 0.1 μm to 5.0 μm, a width of 260 mm to 508 mm, and a thickness of 170 μm to 220 μm.

[0018] In some embodiments, the hydrophobic breathable membrane is made of PTFE.

[0019] Compared with the prior art, the utility model has the beneficial effect of providing a low-cost, low-pollution, fast-response, low-energy-consumption synchronous denitrification ammonia recovery device by combining an electrolytic cell with an ammonia nitrogen recovery device. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is a schematic diagram of an ammonia recovery device for synchronous denitration of the utility model;

[0021] Figure 2 It is a schematic diagram of an electrolytic cell of the utility model;

[0022] Figure 3 This is a schematic diagram of an ammonia nitrogen recovery module of the utility model;

[0023] Figure 4 This is a schematic diagram of an acid solution container of the utility model.

[0024] 1. Bottle of water sample to be treated; 2. Peristaltic pump No. 1; 3. Electrolytic cell; 4. DC regulated power supply; 5. Ammonia nitrogen recovery module; 6. Peristaltic pump No. 2; 7. Three-necked glass bottle; 8. Anode chamber; 9. Cathode chamber; 10. Proton exchange membrane; 11. Hydrophobic breathable membrane; 12. Gas separation chamber; 13. Capture chamber; 14. Polytetrafluoroethylene rotor; 15. Wastewater; 16. Concentrated sulfuric acid; 17. Air duct. DETAILED DESCRIPTION

[0025] 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.

[0026] In the description of the present invention, it should be understood that the terms "upper", "lower", "front", "back", "left", "right", "top", "bottom", "inside", "outside", etc., indicating directions or positional relationships, are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore should not be understood as a limitation on the present invention.

[0027] Reference Figure 1-4 The present embodiment provides an ammonia recovery device for synchronous denitration, comprising a water sample container to be processed, a denitration module, an ammonia nitrogen recovery module 5, and an acidic solution container; the denitration module is an electrolytic cell 3, the ammonia nitrogen recovery module 5 comprises a gas separation chamber 12 and a capture chamber 13, a hydrophobic breathable membrane 11 is arranged between the gas separation chamber 12 and the capture chamber 13, and the capture chamber 13 is connected to the atmosphere through the acidic solution container;

[0028] Specifically, the water sample container to be treated is a water sample bottle 1, which contains wastewater 15 to be treated. Two water pipes, a first water pipe and a second water pipe, are inserted into the water sample bottle 1, wherein the first water pipe is connected to the bottom hole of the cathode chamber 9 of the electrolytic cell 3 after passing through the first fluid conveying device peristaltic pump No. 1 2, so as to connect the water sample bottle 1 and the cathode chamber 9; the second water pipe is directly connected to the upper hole of the anode chamber 8 of the electrolytic cell 3, so as to connect the water sample bottle 1 and the anode chamber 8; the positive pole of the DC regulated power supply 4 is connected to the anode electrode of the anode chamber 8 through an electrical conductor, and the negative pole is connected to the cathode electrode of the cathode chamber 9 through an electrical conductor.

[0029] The anode electrode is a ruthenium-titanium electrode (DSA electrode), which has high current density, low overpotential, and bubbles on the surface between electrodes and electrodes are easy to remove, which can effectively reduce the voltage of the electrochemical cell; the electrode has high catalytic activity, which can effectively improve the reaction efficiency; the shape is easy to make, can be highly precise, and the titanium substrate can be reused. The cathode electrode is composed of a self-produced cathode plate with the ability to selectively reduce nitrate nitrogen to ammonia nitrogen, specifically a cathode plate with foam copper as the substrate and loaded with iron elements; wherein the copper element can increase the adsorption capacity of nitrate nitrogen, and the iron element can increase the selectivity of ammonia nitrogen. The cathode chamber and the anode chamber are separated by a proton exchange membrane 10, and the proton exchange membrane 10 can only pass protons.

[0030] At the same time, the gas separation chamber 12 is connected to two water pipes, the third water pipe and the fourth water pipe; the upper orifice of the cathode chamber 9 is connected to the bottom orifice of the gas separation chamber 12 through the third water pipe, thereby connecting the cathode chamber 9 and the gas separation chamber 12; the upper orifice of the gas separation chamber 12 is connected to the orifice at the bottom of the anode chamber 8 through the fourth water pipe, thereby connecting the gas separation chamber 12 and the anode chamber 8;

[0031] The acid solution container is specifically a three-necked glass bottle 7 containing concentrated sulfuric acid 16 as an acid solution. Two water pipes, namely a fifth water pipe and a sixth water pipe, are inserted into the three-necked glass bottle 7. The fifth water pipe is connected to the bottom opening of the capture chamber 13 through a second fluid conveying device, a peristaltic pump No. 2 6, and the sixth water pipe is directly connected to the upper opening of the capture chamber 13. The three-necked glass bottle 7 is also inserted with an air guide pipe 17 connected to the atmosphere, so that a certain pressure difference is maintained between the gas separation chamber 12 and the capture chamber 13.

[0032] At this point, the water sample container to be treated, the denitrification module, the ammonia nitrogen recovery module, and the acid solution container form a complete synchronous denitrification ammonia recovery device through the water pipe.

[0033] Turn on the DC voltage-stabilized power supply 4 and the switches of the peristaltic pump No. 1 2 and the peristaltic pump No. 2 6. First, the water sample in the water sample bottle 1 reaches the cathode chamber 9 of the electrolytic cell 3 through the peristaltic pump No. 1 2. Then, an electrochemical reduction reaction is carried out in the cathode chamber 9, mainly reducing the nitrate and nitrite in the water sample to ammonium, nitrogen, etc. At the same time, the protons in the water sample migrate to the cathode through the proton exchange membrane 10 and undergo a reduction reaction on the surface of the cathode electrode to form hydrogen, causing the water sample in the cathode chamber 9 to become alkaline. Studies have shown that under the condition of pH 10-11, ammonium ions exist in the form of ammonia molecules. Then, the reduced water sample reaches the bottom of the gas separation chamber 12 through the third water pipe. In order to accelerate the overflow of the gas dissolved in the water sample, a stirring component polytetrafluoroethylene rotor 14 is provided in the gas separation chamber 12. The stirring of the polytetrafluoroethylene rotor 14 accelerates the overflow of the gas in the water sample in the gas separation chamber 12.

[0034] On the one hand, the overflowed gas is due to the hydrophobic and breathable membrane 11 made of PTFE arranged between the gas separation chamber 12 and the capture chamber 13.

[0035] The pore size of the hydrophobic breathable membrane 11 is in the range of 0.1 μm-5.0 μm, the width is 260 mm-508 mm, and the thickness is 170 μm-220 μm. The pore size of the hydrophobic breathable membrane 11 is permeable to gas, but liquid cannot flow through. Under the pressure difference on both sides of the membrane, nitrogen, ammonia and hydrogen in the reduced water sample diffuse from the gas separation chamber 12 to the capture chamber 13, and the water sample flows through the side of the hydrophobic breathable membrane 11 without flowing into the capture chamber, thus completing the separation of gas and liquid without the need for additional energy input.

[0036] On the other hand, the water sample after gas separation directly reaches the upper part of the anode chamber 8 through the fourth water pipe, and undergoes an electrochemical oxidation reaction in the anode chamber 8. At this time, the hydroxide in the water sample undergoes an oxidation reaction on the surface of the anode electrode to form oxygen, causing the water sample in the anode chamber 8 to become acidic. The ammonia nitrogen in the water sample exists in the form of ammonium ions, mainly oxidizing unabsorbed ammonia nitrogen, nitrite, etc. into nitrates. The water sample then reaches the water sample bottle 1 through the second water pipe for a cyclic reaction.

[0037] In the above process, the pressure difference between the gas separation chamber 12 and the capture chamber 13 causes the nitrogen, ammonia and hydrogen in the reduced water sample to diffuse from the gas separation chamber 12 to the capture chamber 13. At this time, the concentrated sulfuric acid 16 in the three-necked glass bottle 7 reaches the bottom of the capture chamber 13 through the fifth water pipe and the peristaltic pump No. 2 6. Under this acidic condition, the ammonia molecules are converted into ammonium ions, reacting with the concentrated sulfuric acid 16 to form ammonium sulfate and completing the recovery of ammonia in this form.

[0038] The reacted ammonium ions, unabsorbed ammonia, nitrogen and hydrogen etc. are transported to the three-necked glass bottle 7 through the sixth water pipe at the upper part of the capture chamber 13, and part of the ammonia continues to react with the concentrated sulfuric acid 16 in the three-necked glass bottle and is recovered. The remaining unabsorbed ammonia, nitrogen, hydrogen etc. are connected to the atmosphere through the air guide pipe 17, so that a certain pressure difference is maintained between the gas separation chamber 12 and the capture chamber 13.

[0039] The cathode chamber 9 and the anode chamber 8 of the synchronous denitration device provided in this embodiment are separated by a proton exchange membrane 10, so that the cathode forms a liquid environment with a higher pH value so that the ammonium ions exist in the form of ammonia molecules, which is convenient for entering the cavity of the capture chamber 13 in the form of gas in the ammonia nitrogen recovery unit and being recovered. At the same time, the anode forms a liquid environment with a lower pH value, so that the ammonia nitrogen that has not entered the cavity of the capture chamber 13 exists in the form of ammonium ions, which is convenient for the subsequent oxidation reaction on the anode electrode. The maximum recovery efficiency of ammonia nitrogen is guaranteed, which greatly saves processing time and energy consumption.

[0040] The gas separation chamber 12 cavity and the capture chamber 13 cavity are separated by a hydrophobic breathable membrane 11, and ammonia nitrogen is recovered by membrane extraction. The hydrophobic breathable membrane 11 provides a mass transfer interface, and the ammonia nitrogen wastewater containing ammonia gas and the like in the gas separation chamber 12 cavity and the concentrated sulfuric acid 16 in the capture chamber 13 flow through both sides of the membrane respectively, and then the pressure difference on both sides of the membrane causes ammonia gas and the like to diffuse into the capture chamber 13 and react with sulfuric acid to generate ammonium sulfate. The nitrogen therein is ammonia nitrogen, which can be directly absorbed by crops, and with high solubility, it is a fast-acting nitrogen fertilizer. This device turns waste into treasure, protects the environment, and converts harmful ammonia nitrogen into ammonia fertilizer, saving a lot of resources.

[0041] The ammonia recovery device for simultaneous denitrification provided in this embodiment has the advantages of low cost, low pollution, fast reaction and low energy consumption.

[0042] 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. An ammonia recovery device for synchronous denitration, comprising a water sample container to be treated, a denitration module, and an ammonia nitrogen recovery module, wherein the ammonia nitrogen generated by the reaction of the denitration module is recovered in the ammonia nitrogen recovery module, characterized in that: The denitration module is an electrolytic cell; the ammonia nitrogen recovery module includes a gas separation chamber and a capture chamber, a hydrophobic breathable membrane is arranged between the gas separation chamber and the capture chamber, and the capture chamber is connected to the atmosphere through an acid solution container; The water sample container to be processed is connected to the cathode chamber of the electrolytic cell to transport the water sample to be processed to the cathode chamber for reaction, the cathode chamber of the electrolytic cell is connected to the gas separation chamber to transmit the water sample after the reduction reaction, the gas separation chamber is connected to the anode chamber of the electrolytic cell to transmit the water sample after gas separation, and the anode chamber is connected to the water sample container to be processed to transmit the unreacted water sample to the cathode chamber for cyclic electrolysis; The acid solution container is communicated with the capture chamber to transport the acid solution to the capture chamber to react with ammonia nitrogen.

2. The ammonia recovery device for synchronous denitration according to claim 1, characterized in that: The cathode chamber and the anode chamber are separated by a proton exchange membrane; the anode chamber is provided with an anode electrode connected to the positive electrode of the power supply, and the cathode chamber is provided with a cathode electrode connected to the negative electrode of the power supply.

3. The ammonia recovery device for synchronous denitration according to claim 1, characterized in that: The treated water sample container is provided with a first water pipe and a second water pipe. The first water pipe is connected to the cathode chamber through a first fluid conveying device, and the second water pipe is connected to the anode chamber. The height of the second water pipe opening in the anode chamber is higher than that in the treated water sample container.

4. The ammonia recovery device for synchronous denitration according to claim 1, characterized in that: The cathode chamber is connected to the gas separation chamber through a third water pipe, and the height of the third water pipe opening in the cathode chamber is higher than that in the gas separation chamber; the gas separation chamber is connected to the anode chamber through a fourth water pipe, and the height of the fourth water pipe opening in the gas separation chamber is higher than that in the anode chamber.

5. The ammonia recovery device for synchronous denitration according to claim 1, characterized in that: The acidic solution container includes a fifth water pipe and a sixth water pipe. The fifth water pipe is connected to the capture chamber through a second fluid conveying device. The sixth water pipe is communicated with the capture chamber. The height of the sixth water pipe opening in the capture chamber is higher than that in the ammonia reaction container.

6. The ammonia recovery device for synchronous denitration according to claim 1, characterized in that: The acid solution container is provided with an air guide pipe which is connected with the atmosphere.

7. The ammonia recovery device for synchronous denitration according to claim 1, characterized in that: A stirring component is arranged in the gas separation chamber.

8. The ammonia recovery device for synchronous denitration according to claim 1, characterized in that: The acidic solution is concentrated sulfuric acid.

9. The ammonia recovery device for synchronous denitration according to claim 1, characterized in that: The hydrophobic breathable membrane has a pore size range of 0.1 μm-5.0 μm, a width of 260 mm-508 mm, and a thickness of 170 μm-220 μm.

10. The ammonia recovery device for synchronous denitration according to claim 9, characterized in that: The hydrophobic breathable membrane is made of PTFE.

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