CN110845054A - Method and device for enhanced denitrification and nitrogen and phosphorus recovery by struvite cyclic crystallization method - Google Patents
Method and device for enhanced denitrification and nitrogen and phosphorus recovery by struvite cyclic crystallization method Download PDFInfo
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- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/46—Treatment of water, waste water, or sewage by electrochemical methods
- C02F1/461—Treatment of water, waste water, or sewage by electrochemical methods by electrolysis
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Abstract
The invention relates to the field of a method and a device for enhanced denitrification and nitrogen and phosphorus recovery by a struvite cyclic crystallization method. The method comprises the following steps: adding a sodium chloride solution and struvite crystals into an electrolytic tank, introducing 5-12V direct current to an electrolytic device, adjusting the pH value to 8-10, introducing air into the electrolytic tank through an aeration head of an aeration device, and reacting for 150 minutes to obtain a solid-liquid mixed electrolysis product containing magnesium salts and phosphates; introducing the high-concentration ammonia nitrogen wastewater filtered by the sand filtration system into an electrolytic cell through a conduit, mixing the high-concentration ammonia nitrogen wastewater with the obtained solid-liquid mixed electrolysis product containing magnesium salt and phosphate, adjusting the pH value to 8-10, and stirring the mixture at room temperature for 120 minutes to obtain precipitated struvite solid and wastewater; and when the removal rate of the ammonia nitrogen is reduced, the ammonia nitrogen concentration in the solution is unchanged or the ammonia nitrogen concentration in the solution is increased, the circulation is stopped. The method has the greatest beneficial effect that the electrolytic product of the struvite crystal can be repeatedly utilized to realize the resource recovery of nitrogen and phosphorus in the high ammonia-nitrogen wastewater.
Description
Technical Field
The invention relates to the technical field of sewage treatment, in particular to the field of a method and a device for enhanced denitrification and nitrogen and phosphorus recovery by a struvite cyclic crystallization method.
Background
Nitrogen and phosphorus are one of indispensable elements of life substances, and phosphorus is a non-renewable limited resource on the earth. For most of high-nitrogen and phosphorus wastewater, if the wastewater is not pretreated, the treatment load of a biological treatment system is too high, so that the operation problem is caused. The traditional chemical nitrogen and phosphorus removal process cannot solve the defects of large chemical sludge production and recycling of nitrogen and phosphorus resources. Therefore, in order to recover nitrogen and phosphorus from nitrogen and phosphorus wastewater, the problem of water eutrophication can be improved, and the nitrogen and phosphorus can be recycled, so that the method is widely concerned.
Among the methods for recovering nitrogen and phosphorus elements in various forms, the struvite crystallization method has high nitrogen and phosphorus content, can be directly or indirectly used as a slow-release fertilizer, cannot damage the root system of a plant, and cannot cause water eutrophication due to the characteristic that the struvite crystallization method is difficult to dissolve in water, so that the struvite crystallization method is very suitable for being used as a phosphate fertilizer for vegetation in gardens, nurseries and the like, and can also be prepared into a detergent, a cosmetic and an animal feed.
At present, the domestic and foreign treatment methods for nitrogen and phosphorus wastewater mainly comprise biological methods, physical methods and chemical methods. The biological method mainly adopts an A-O process, the process is mature but is mostly suitable for treating ammonia nitrogen wastewater with lower concentration (the ammonia nitrogen concentration is less than 200mg/L), the ammonia nitrogen wastewater with the concentration of more than 1000mg/L can seriously inhibit nitrobacteria in the method, and a large amount of sludge can be generated. Although the physical method is more suitable for treating nitrogen and phosphorus wastewater, the treatment cost is higher, the operation is strict, and secondary pollution is easily caused. The chemical methods mainly include breakpoint chlorination and chemical precipitation, but the chemical methods have high administration cost and are prone to generate new chemical pollution.
Struvite is also known as magnesium ammonium phosphate hexahydrate (MgNH)4PO4·6H2O), is a white crystal mineral which is insoluble in water and has a rhombohedral crystal structure. Solubility at 0 ℃ is only 0.023g/L, Mg in water2+、NH4 +And PO4 3-The ion solubility product in water is more than 2.5 multiplied by 10-13Then, spontaneous crystallization occurs to produce struvite precipitate.
The struvite crystallization method for treating nitrogen and phosphorus wastewater has the following basic principle: soluble magnesium salt and phosphate are added into the nitrogen and phosphorus wastewater to react with the nitrogen and phosphorus in the wastewater to generate magnesium ammonium phosphate precipitate. The existing research shows that the removal rate of ammonia nitrogen and phosphorus can reach more than 90 percent by treating slaughter house wastewater containing high-concentration nitrogen and phosphorus by a struvite crystallization method; the method can treat high-concentration nitrogen and phosphorus wastewater of a fertilizer plant, the removal rate of ammonia nitrogen and phosphorus can reach more than 95%, and the recovery rate of nitrogen and phosphorus can reach 80%.
The struvite crystallization method has high cost for treating high-concentration nitrogen and phosphorus wastewater, and the main treatment cost is the cost for precipitating magnesium salts and phosphates. According to the literature report, the cost for treating the landfill leachate by using a struvite crystallization method is 3.89-7.10 yuan/m3Higher cost compared with other treatment methods
Disclosure of Invention
The invention aims to disclose a method and a device for strengthening denitrification and recovering nitrogen and phosphorus in wastewater by an electrolytic struvite cyclic crystallization method.
The invention is realized by the following steps:
a method for strengthening denitrification and recovering nitrogen and phosphorus by a struvite cyclic crystallization method comprises the following steps:
(1) adding a sodium chloride solution and struvite crystals into an electrolytic tank, introducing 5-12V direct current to an electrolytic device, adjusting the pH value to 8-10, introducing air into the electrolytic tank through an aeration head of an aeration device, reacting for 150 minutes to obtain a solid-liquid mixed electrolysis product containing magnesium salts and phosphates, and turning off a power supply;
(2) introducing the high-concentration ammonia nitrogen wastewater filtered by the sand filtration system into an electrolytic cell through a conduit, mixing the high-concentration ammonia nitrogen wastewater with the solid-liquid mixed electrolysis product containing magnesium salt and phosphate obtained in the step (1), adjusting the pH value to 8-10, stirring at room temperature for 120 minutes, standing after the reaction is finished, and obtaining precipitated struvite solid and wastewater;
(3) and (3) repeating the step (1) and the step (2), and stopping circulation when the ammonia nitrogen removal rate is reduced, the ammonia nitrogen concentration in the solution is unchanged or the ammonia nitrogen concentration in the solution is increased.
In the step (1), the anode electrode adopted by the electrolytic cell is a graphite plate or stainless steel plate inert electrode, and the cathode electrode is a graphite plate or stainless steel plate inert electrode.
In the step (1), the salt content of the sodium chloride solution is not lower than 3%.
In the step (2), 0.05-2.00 kg of magnesium salt is added into per cubic meter of wastewater after the high-concentration ammonia nitrogen wastewater is introduced into the electrolytic cell.
A device for strengthening denitrification and recovering nitrogen and phosphorus by a struvite cyclic crystallization method comprises: the device comprises an electrolytic tank (1), a water inlet (2), a water outlet (3), a sampling port (4), an external power supply (5), an anode electrode (51), a cathode electrode (52), an external circuit (53), a struvite precipitation recovery tank (6), a struvite precipitation recovery tank conduit (61), an aeration device (7), an aeration device aeration pipe (71), an aeration device aeration head (72), a stirring paddle (73), a sodium chloride solution dosing pipe (9), a flowmeter (91), a medicament tank (10) and a metering pump (11), wherein the struvite precipitation recovery tank (6) is arranged at the lower part of the electrolytic tank (1), the struvite precipitation recovery tank conduit (61) is connected to the bottom of the struvite precipitation recovery tank (6), the water inlet (2) is arranged at the left side of the electrolytic tank (1), the water outlet (3) and the sampling port (4) are arranged at the right side of the electrolytic tank, the sodium chloride solution dosing pipe (9) is connected with, the setting is in the outside right side of electrolytic bath (1), and inside flowmeter (91) stretched into electrolytic bath (1) through the pipeline, medicament groove (10) linked to each other through the pipeline with medicament pump (11), sets up in the outside of electrolytic bath (1), and medicament pump (11) stretch into inside electrolytic bath (1) through the pipeline.
The anode electrode (51) and the cathode electrode (52) are positioned in the electrolytic cell (1), the anode electrode (51) is arranged on one side close to the water inlet (2), the cathode electrode (52) is arranged on one side close to the water outlet (3), and an external power supply (5) and an external circuit (53) are connected between the anode electrode (51) and the cathode electrode (52).
The aeration device (7) is communicated with an aeration head (71) of the aeration device through an aeration pipe (71) of the aeration device, and the aeration device (7) extends into the electrolytic tank (1) through the aeration pipe (71) of the aeration device.
The invention has the beneficial effects that: the invention obtains the electrolytic product of magnesium ammonium phosphate crystal through the electrolytic reaction of the electrolytic cell after simply removing impurities from the high ammonia nitrogen wastewater, so that NH in the high ammonia nitrogen wastewater4 +Can evenly and quickly form struvite sediment and recycle the struvite sediment. The device has the greatest beneficial effect that the recycling of nitrogen and phosphorus in the high ammonia nitrogen wastewater can be realized by repeatedly utilizing the electrolysis product of the struvite crystal.
Drawings
FIG. 1 is a schematic structural diagram of a device for enhanced denitrification and nitrogen and phosphorus recovery by a struvite cyclic crystallization method.
Detailed Description
The invention will be further explained with reference to the drawings.
The invention relates to the technical field of sewage treatment, in particular to the field of a method and a device for enhanced denitrification and nitrogen and phosphorus recovery by a struvite cyclic crystallization method.
The invention aims to disclose a method for strengthening denitrification and recovering nitrogen and phosphorus in wastewater by an electrolytic struvite cyclic crystallization method, which has a good denitrification effect on high-concentration ammonia nitrogen wastewater, and can recover and recycle ammonia nitrogen and phosphorus in a struvite form, thereby achieving beneficial effects on environment and economy.
In order to achieve the purpose, aiming at the defect of high treatment cost of a struvite crystallization method, the struvite solid collected by precipitation is electrolyzed in a sodium chloride solution to obtain a solid electrolysis product only containing magnesium salt and phosphate, and simultaneously, nitrogen generated by electrolysis is recovered; and the solid electrolysis product containing magnesium salt and phosphate is used for treating the wastewater again to obtain struvite, the struvite is recycled for several times, the utilization of the magnesium salt and the phosphate is fully improved, and finally the struvite which cannot be recycled is recovered as a slow-release fertilizer. The method ensures higher nitrogen and phosphorus removal rate, greatly reduces the treatment cost of high-concentration ammonia nitrogen wastewater, fully recycles beneficial nitrogen and phosphorus resources, and is innovation and development of the traditional struvite crystallization technology.
Adding a sodium chloride solution and a certain amount of struvite crystals into an electrolytic tank, introducing direct current with a certain voltage to an electrolytic device, introducing a certain amount of air to an aeration head of an aeration system, reacting for a period of time to obtain a solid-liquid mixed electrolysis product containing magnesium salts and phosphate, and turning off a power supply; introducing the high-concentration ammonia nitrogen wastewater filtered by a sand filtration system into an electrolytic cell through a conduit, mixing the high-concentration ammonia nitrogen wastewater with the solid-liquid mixed electrolysis product containing magnesium salt and phosphate obtained in the step (1), stirring the mixture at room temperature, and reacting for a period of time to obtain precipitated struvite and wastewater; reusing the struvite collected by precipitation, adding a small amount of magnesium salt, mixing with a sodium chloride solution, and electrolyzing to generate struvite again; and (4) electrolyzing the struvite, and treating the high-concentration ammonia nitrogen wastewater again by using an electrolysis product, and circulating for several times. The treated wastewater is clear, and the ammonia nitrogen concentration is greatly reduced.
The specific process steps are as follows:
adding a sodium chloride solution and a certain amount of struvite crystals into an electrolytic tank, introducing 5-12V direct current to an electrolytic device, adjusting the pH value to 8-10, introducing a certain amount of air into the electrolytic tank through an aeration head of an aeration device, reacting for 150 minutes to obtain a solid-liquid mixed electrolysis product containing magnesium salts and phosphate, and turning off a power supply;
secondly, leading the high-concentration ammonia nitrogen wastewater filtered by a sand filtration system to 426-2846 mg/L into an electrolytic cell through a guide pipe, mixing the wastewater with the solid-liquid mixed electrolysis product containing magnesium salt and phosphate obtained in the step (1), adjusting the pH value to 8-10, stirring the mixture at room temperature for 120 minutes, and standing the mixture after the reaction is finished to obtain precipitated struvite solid and wastewater;
and repeating the first step and the second step for 3-5 times, obviously reducing the removal rate of ammonia nitrogen, stopping circulation when the concentration of ammonia nitrogen in the solution is not obviously changed or has a rising trend, and using the struvite which cannot be reused as a slow release fertilizer.
And the electrolytic cell is used for electrolyzing the pretreated high ammonia nitrogen wastewater to provide a reaction site.
The aeration system consisting of the aeration device, the aeration pipe of the aeration device and the aeration head of the aeration device is used for aerating the electrolytic tank and aims at playing a role in stirring air.
The electrolysis device is an electrolysis reaction system of an electrolytic cell, adopts conductive substances as an anode electrode and a cathode electrode, and adopts a direct current power supply as an external power supply. The working principle is as follows: an electrolysis device consisting of an external power supply, an anode electrode, a cathode electrode and an external circuit and used for electrolyzing the added sodium chloride solution and magnesium ammonium phosphate crystal to decompose the magnesium ammonium phosphate crystal in an electrolytic cell and generate MgHPO4·3H20 and Mg3(PO4)2·22H20. The reaction formula is as follows:
2Cl--2e-→Cl2
Cl2+H20→HOCl+H++Cl-
2NH4 ++3HOCl→N2+5H++3Cl-+3H20
MgNH4PO4·6H20+H+→Mg2++NH4 ++HPO4 2-+6H20
Mg2++HPO4 2-+3H20→MgHPO4·3H20
3Mg2++2H2PO4 -+22H20→Mg3(PO4)2·22H20+4H+
after reacting for a period of time, turning off the power supply, leading the high ammonia nitrogen wastewater pretreated by the sand filtration system into an electrolytic cell through a conduit, turning on a stirring paddle, and reacting for a certain period of time to obtain the precipitated struvite and wastewater.
The settled struvite is scraped manually or automatically and is recycled.
The struvite precipitation recovery tank is used for collecting and recycling struvite formed in the electrolytic cell.
At the moment, the pretreated high ammonia nitrogen wastewater is mixed with an electrolysis product, and MgHPO in an electrolytic cell4·3H20 and Mg3(PO4)2·22H20 reabsorb ammonium ions in the water, forming struvite precipitates. The reaction formula is as follows:
MgHPO4+NH4 ++6H20→MgNH4PO4·6H20+H+
and recovering the struvite crystals, putting the recovered struvite crystals into an electrolytic cell again, electrolyzing the struvite crystals under the action of a sodium chloride solution, and continuously absorbing ammonium ions in the wastewater by using an electrolysis product.
The invention is further described as follows:
a method for strengthening denitrification and recovering nitrogen and phosphorus in wastewater by utilizing an electrolytic struvite cyclic crystallization method comprises the following steps:
first, electrolyzing struvite solution
Adding a sodium chloride solution and a certain amount of struvite crystals into an electrolytic tank, introducing 5-12V direct current to an electrolytic device, adjusting the pH value to 8-10, introducing a certain amount of air into the electrolytic tank through an aeration head of an aeration device, reacting for 150 minutes to obtain a solid-liquid mixed electrolysis product containing magnesium salts and phosphates, and turning off a power supply;
secondly, treating high-concentration ammonia nitrogen wastewater by using struvite electrolysis product
Introducing the high-concentration ammonia nitrogen wastewater filtered by a sand filtration system into an electrolytic cell through a conduit, mixing the high-concentration ammonia nitrogen wastewater with a solid-liquid mixed electrolysis product containing magnesium salt and phosphate obtained in the first step, adjusting the pH value to be 8-10, stirring the mixture at room temperature for 120 minutes, and standing the mixture after the reaction is finished to obtain precipitated struvite and wastewater;
thirdly, treating the high-concentration ammonia nitrogen wastewater by using a struvite electrolysis product
And repeating the first step and the second step for 3-5 times, obviously reducing the removal rate of ammonia nitrogen, stopping circulation when the concentration of ammonia nitrogen in the solution is not obviously changed or has a rising trend, and using the struvite which cannot be reused as a slow release fertilizer.
And in the first step, inert electrodes such as graphite plates or stainless steel plates are adopted as the anode and the cathode.
And in the second step, when the solid-liquid mixed product containing magnesium salt and phosphate obtained by electrolysis is added into high-concentration ammonia nitrogen wastewater to be treated, wherein the ammonia nitrogen concentration of the ammonia nitrogen wastewater is 426-2846 mg/L, 0.05 kg-2.00 kg of magnesium salt is added into per cubic meter of wastewater, so that the nitrogen removal effect can be enhanced.
The sodium chloride solution contains more than 3% of salt.
As shown in fig. 1, the device comprises an electrolytic cell (1), a water inlet (2), a water outlet (3), a sampling port (4), an external power supply (5), an anode electrode (51), a cathode electrode (52), an external circuit (53), a struvite precipitation recovery tank (6), a struvite precipitation recovery tank conduit (61), an aeration device (7), an aeration device aeration pipe (71), an aeration device aeration head (72), a stirring paddle (73), a sodium chloride solution feeding pipe (9), a flow meter (91), a medicament tank (10) and a metering pump (11); a struvite precipitation recovery tank (6) is arranged at the lower part of the electrolytic tank (1), a struvite precipitation recovery tank guide pipe (61) is arranged at the bottom of the struvite precipitation recovery tank (6), a water inlet (2) is arranged at the left side of the electrolytic tank (1), a water outlet (3) and a sampling port (4) are arranged at the right side of the electrolytic tank (1), an anode electrode (51) and a cathode electrode (52) are positioned inside the electrolytic tank (1), an external power supply (5) and an external circuit (53) are connected between the anode electrode (51) and the cathode electrode (52), an aeration head (72) of the aeration device is positioned inside the electrolytic tank (1), the aeration head (72) of the aeration device is communicated with an aeration device (7) through an aeration pipe (71) of the aeration device, a stirring paddle (8) is required to be arranged when the aeration device (7) stretches into the electrolytic tank (1) through the aeration pipe (71) of the aeration device, a sodium chloride solution, the chemical tank (10) is connected with the chemical pump (11), and the sodium chloride solution dosing pipe (9), the flowmeter (91), the chemical tank (10) and the chemical pump (11) are respectively arranged outside the electrolytic cell (1) and extend into the electrolytic cell (1) through a pipeline.
The anode electrode (51) adopts a graphite plate or a graphite rod, and the cathode electrode (52) adopts a graphite plate or a graphite rod.
The working process of the example is as follows:
adding a sodium chloride solution and a certain amount of struvite crystals into an electrolytic tank, introducing 5-12V direct current to an electrolytic device, adjusting the pH value to 8-10, introducing a certain amount of air into the electrolytic tank through an aeration head of an aeration device, reacting for 150 minutes to obtain a solid-liquid mixed electrolysis product containing magnesium salts and phosphates, and turning off a power supply;
introducing the high-concentration ammonia nitrogen wastewater filtered by a sand filtration system into an electrolytic cell through a conduit, mixing the high-concentration ammonia nitrogen wastewater with a solid-liquid mixed electrolysis product containing magnesium salt and phosphate obtained in the first step, adjusting the pH value to be 8-10, stirring the mixture at room temperature for 120 minutes, and standing the mixture after the reaction is finished to obtain precipitated struvite and wastewater;
and repeating the first step and the second step for 3-5 times, obviously reducing the removal rate of ammonia nitrogen, stopping circulation when the concentration of ammonia nitrogen in the solution is not obviously changed or has a rising trend, and using the struvite which cannot be reused as a slow release fertilizer.
The first embodiment is as follows:
adding magnesium ammonium phosphate crystal and a certain amount of sodium chloride solution through a dosing pipe, introducing direct current with the voltage of 7V to an electrolysis device, wherein a graphite steel plate is adopted as a cathode electrode, reacting for 150 minutes, and then adding NH4 +The simulated high ammonia nitrogen wastewater with the concentration of 600mg/L passes through the system to obtain struvite sediment, namely NH4 +The removal rate of (2) reaches 91.35%.
Example two:
adding magnesium ammonium phosphate crystal and a certain amount of sodium chloride solution through a dosing pipe, introducing direct current with the voltage of 7V to an electrolysis device, wherein a graphite steel plate is adopted as a cathode electrode, reacting for 150 minutes, and then adding NH4 +The simulated high ammonia nitrogen wastewater with the concentration of 800mg/L passes through the system to obtain struvite sediment, namely NH4 +The removal rate of (A) reaches 90.69%.
Example three:
adding magnesium ammonium phosphate crystal and a certain amount of sodium chloride solution through a dosing pipe, introducing direct current with the voltage of 7V to an electrolysis device, wherein a graphite steel plate is adopted as a cathode electrode, reacting for 150 minutes, and then adding NH4 +Mold with concentration of 1000mg/LThe wastewater with high ammonia nitrogen content is treated by the system to obtain struvite sediment and NH4 +The removal rate of (2) reaches 90.27%.
In conclusion, the invention relates to a method for strengthening denitrification and recovering nitrogen and phosphorus in wastewater by utilizing an electrolytic struvite cyclic crystallization method, which comprises the steps of adding a sodium chloride solution and a certain amount of pure struvite crystals into an electrolytic cell, introducing direct current with a certain voltage into an electrolytic device, introducing a certain amount of air into an aeration head of an aeration system, reacting for a period of time to obtain a solid-liquid mixed electrolysis product containing magnesium salts and phosphate, and turning off a power supply; secondly, leading the high-concentration ammonia nitrogen wastewater filtered by a sand filtration system into an electrolytic cell through a conduit, mixing the high-concentration ammonia nitrogen wastewater with the solid-liquid mixed electrolysis product containing magnesium salt and phosphate obtained in the first step, placing the mixture at room temperature, stirring the mixture, and reacting the mixture for a period of time to obtain precipitated struvite and wastewater; thirdly, recycling the collected struvite sediment, adding a small amount of magnesium salt, mixing with a sodium chloride solution, electrolyzing, and repeating the first step and the second step; fourthly, the struvite which can not be reused is used as a slow release fertilizer. For high ammonia nitrogen wastewater with the ammonia nitrogen concentration of 426-2846 mg/L, the struvite obtained by the method can be recycled for 3-5 times, the ammonia nitrogen removal rate is higher than 90%, the purity of the obtained struvite crystal is higher than 87%, and the recycling saves medicaments and recovers nitrogen and phosphorus resources.
Claims (7)
1. A method for strengthening denitrification and recovering nitrogen and phosphorus by a struvite cyclic crystallization method is characterized by comprising the following steps: the method comprises the following steps:
(1) adding a sodium chloride solution and struvite crystals into an electrolytic tank, introducing 5-12V direct current to an electrolytic device, adjusting the pH value to 8-10, introducing air into the electrolytic tank through an aeration head of an aeration device, reacting for 150 minutes to obtain a solid-liquid mixed electrolysis product containing magnesium salts and phosphates, and turning off a power supply;
(2) introducing the high-concentration ammonia nitrogen wastewater filtered by the sand filtration system into an electrolytic cell through a conduit, mixing the high-concentration ammonia nitrogen wastewater with the solid-liquid mixed electrolysis product containing magnesium salt and phosphate obtained in the step (1), adjusting the pH value to 8-10, stirring the mixture at room temperature for 120 minutes, and standing the mixture after the reaction is finished to obtain precipitated struvite solid and wastewater;
(3) and (3) repeating the step (1) and the step (2), and stopping circulation when the ammonia nitrogen removal rate is reduced, the ammonia nitrogen concentration in the solution is unchanged or the ammonia nitrogen concentration in the solution is increased.
2. The method for enhanced nitrogen removal and nitrogen and phosphorus recovery by struvite cyclic crystallization according to claim 1, which is characterized in that: in the step (1), the anode electrode adopted by the electrolytic cell is a graphite plate or stainless steel plate inert electrode, and the cathode electrode is a graphite plate or stainless steel plate inert electrode.
3. The method for enhanced nitrogen removal and nitrogen and phosphorus recovery by struvite cyclic crystallization according to claim 1, which is characterized in that: in the step (1), the salt content of the sodium chloride solution is not lower than 3%.
4. The method for enhanced nitrogen removal and nitrogen and phosphorus recovery by struvite cyclic crystallization according to claim 1, which is characterized in that: in the step (2), 0.05-2.00 kg of magnesium salt is added into per cubic meter of wastewater after the high-concentration ammonia nitrogen wastewater is introduced into the electrolytic cell.
5. A device for strengthening denitrification and recovering nitrogen and phosphorus by a struvite cyclic crystallization method comprises: electrolytic cell (1), water inlet (2), delivery port (3), sample connection (4), applied power supply (5), anode electrode (51), cathode electrode (52), outer circuit (53), struvite deposits accumulator (6), struvite deposits accumulator pipe (61), aeration equipment (7), aeration equipment aeration pipe (71), aeration equipment aeration head (72), stirring rake (73), sodium chloride solution dosing pipe (9), flowmeter (91), medicament groove (10), measuring pump (11), characterized by: electrolytic cell (1) lower part is struvite precipitation accumulator (6), the bottom of struvite precipitation accumulator (6) is connected with struvite precipitation accumulator pipe (61), the left side of electrolytic cell (1) is equipped with water inlet (2), the right side is equipped with delivery port (3) and sample connection (4), sodium chloride solution dosing pipe (9) link to each other through the pipeline with flowmeter (91), the setting is in the outside right side of electrolytic cell (1), flowmeter (91) stretch into to electrolytic cell (1) inside through the pipeline, medicament groove (10) link to each other through the pipeline with medicament pump (11), the setting is in the outside of electrolytic cell (1), medicament pump (11) stretch into to electrolytic cell (1) inside through the pipeline.
6. The device for enhanced nitrogen removal and nitrogen and phosphorus recovery by struvite cyclic crystallization according to claim 5, which is characterized in that: the anode electrode (51) and the cathode electrode (52) are positioned in the electrolytic cell (1), the anode electrode (51) is arranged on one side close to the water inlet (2), the cathode electrode (52) is arranged on one side close to the water outlet (3), and an external power supply (5) and an external circuit (53) are connected between the anode electrode (51) and the cathode electrode (52).
7. The device for enhanced nitrogen removal and nitrogen and phosphorus recovery by struvite cyclic crystallization according to claim 5, which is characterized in that: the aeration device (7) is communicated with an aeration head (71) of the aeration device through an aeration pipe (71) of the aeration device, and the aeration device (7) extends into the electrolytic tank (1) through the aeration pipe (71) of the aeration device.
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Cited By (4)
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| CN111362372A (en) * | 2020-04-16 | 2020-07-03 | 王招 | Synchronous nitrogen and phosphorus removal system of electrochemistry |
| CN111453837A (en) * | 2020-06-21 | 2020-07-28 | 山东龙安泰环保科技有限公司 | Bioelectrochemical device for synchronous sewage treatment and nitrogen and phosphorus recovery |
| CN116395895A (en) * | 2023-04-21 | 2023-07-07 | 江苏源泰恒环境工程有限公司 | Multistage efficient biological aerated filter and sewage treatment process |
| CN116606020A (en) * | 2023-06-06 | 2023-08-18 | 武汉碳环生态有限公司 | Method for separating ammonia nitrogen from kitchen waste biogas slurry |
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| CN207072877U (en) * | 2017-08-21 | 2018-03-06 | 吉林大学 | A kind of electro-chemical systems of high ammonia nitrogen and high phosphorized waste water recycling |
| CN108862827A (en) * | 2018-06-21 | 2018-11-23 | 湖南双晟科技信息咨询有限公司 | A kind of processing method of ammonia nitrogen waste water |
| CN108975626A (en) * | 2018-08-18 | 2018-12-11 | 江苏澳洋生态园林股份有限公司 | A kind of landscape water treatment device with recovery of nitrogen and phosphorus effect |
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| CN207072877U (en) * | 2017-08-21 | 2018-03-06 | 吉林大学 | A kind of electro-chemical systems of high ammonia nitrogen and high phosphorized waste water recycling |
| CN108862827A (en) * | 2018-06-21 | 2018-11-23 | 湖南双晟科技信息咨询有限公司 | A kind of processing method of ammonia nitrogen waste water |
| CN108975626A (en) * | 2018-08-18 | 2018-12-11 | 江苏澳洋生态园林股份有限公司 | A kind of landscape water treatment device with recovery of nitrogen and phosphorus effect |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111362372A (en) * | 2020-04-16 | 2020-07-03 | 王招 | Synchronous nitrogen and phosphorus removal system of electrochemistry |
| CN111453837A (en) * | 2020-06-21 | 2020-07-28 | 山东龙安泰环保科技有限公司 | Bioelectrochemical device for synchronous sewage treatment and nitrogen and phosphorus recovery |
| CN116395895A (en) * | 2023-04-21 | 2023-07-07 | 江苏源泰恒环境工程有限公司 | Multistage efficient biological aerated filter and sewage treatment process |
| CN116606020A (en) * | 2023-06-06 | 2023-08-18 | 武汉碳环生态有限公司 | Method for separating ammonia nitrogen from kitchen waste biogas slurry |
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