TWM463735U - Ammonia/nitrogen waste water treatment system - Google Patents

Description

Ammonia nitrogen wastewater treatment system

This creation is about an ammonia nitrogen wastewater treatment system, especially an ammonia nitrogen wastewater treatment system that can increase the ammonia nitrogen removal rate.

With the growth of the world population and the rapid development of industrial and agricultural production, quite a lot of complicated chemicals have entered the water body and polluted the water quality. When people realize the effect of ammonia nitrogen on water eutrophication, the treatment goal of wastewater is developed to the stage of removal of organic matter and ammonia nitrogen. According to the difference of ammonia nitrogen concentration in wastewater, wastewater can be divided into three categories: high concentration ammonia nitrogen wastewater (NH3-N>500mg/L), medium concentration ammonia nitrogen wastewater (NH3-N: 50-500mg/L), low concentration ammonia nitrogen wastewater (NH3-N < 50 mg/L). So far, domestic and foreign ammonia nitrogen wastewater treatment has various methods such as chlorination, ion exchange, biological deamination, chemical precipitation, stripping and stripping.

The chemical process of oxidizing NH3-N in wastewater to N2 by the chlorination method is the lowest in the water. When the chlorine gas reaches a certain point in the wastewater, the free chlorine content in the water is the lowest, and the ammonia concentration is reduced to Zero, when the chlorine gas intake exceeds this point, the free chlorine in the water increases, so this point is called a break point, and the chlorination in this state is called cleavage. The most prominent advantage of the chlorination method is that it can properly reduce the amount of chlorine added and homogenize the flow rate, so that all ammonia nitrogen in the wastewater is reduced to zero, and the wastewater is disinfected. For low concentration ammonia nitrogen wastewater, this method is more economical. The removal rate of the chlorination method is about 90%~100%, the treatment effect is stable, and it is not affected by the water temperature, but the operation cost is high. The by-product chloramine and chlorinated organic matter will cause secondary pollution, and the chlorination method only Suitable for treating low concentration ammonia nitrogen wastewater.

The ion exchange method refers to an ion exchange process occurring at the interface between solid particles and a liquid. The ion exchange method uses zeolite which has strong selectivity to NH4+ ions as an exchange resin. And to achieve the purpose of removing ammonia nitrogen. The ion exchange method uses zeolite as a separator for separating ammonia nitrogen from wastewater and a carrier for nitrifying bacteria in a simple reactor in two stages of adsorption and biological regeneration. In the adsorption stage, the zeolite column acts as a typical ion exchange column, and in the biological regeneration stage, the bacteria attached to the zeolite oxidize the desorbed ammonia nitrogen to nitrate nitrogen. The ion exchange method is suitable for medium and low concentration ammonia nitrogen wastewater, and the maximum removal rate can reach more than 90%, but it has large resin consumption, difficult regeneration, high management cost, secondary pollution, and high concentration waste liquid generated during regeneration. And so on.

The biological deamination method refers to a series of reactions such as nitrification and denitrification under the action of various microorganisms under the action of various microorganisms, thereby finally forming nitrogen gas, thereby achieving the purpose of removing ammonia nitrogen. There are many processes for biological deamination, but the mechanism is basically the same. Both need to go through two stages of nitrification and denitrification. The removal rate of biological nitrogen removal method is about 70%~95%, the secondary pollution is small and economical, but the disadvantage is that the area is large, the efficiency is low at low temperature, and the high concentration of ammonia nitrogen wastewater has an inhibitory effect on the activity of microorganisms. It restricts the application and effect of biochemical methods, and at the same time reduces the degradation efficiency of biochemical systems to organic pollutants, which makes it difficult to meet the requirements of treated effluent.

The chemical precipitation method is based on the nature of the pollutants in the wastewater. If necessary, a certain chemical raw material is added, and the chemical reaction is carried out under certain process conditions, so that the pollutants in the wastewater form precipitates or polymers with little solubility, or are insoluble. The gaseous product of water, thereby purifying the wastewater, or achieving a certain removal rate, adding a chemical precipitant Mg(OH)2, H3PO4 and NH4+ to form MgNH4PO4‧6H2O (streptite) precipitate in the ammonia nitrogen wastewater, the precipitate After the process of granulation and other processes, it can be developed and used as a fertilizer. The factors affecting the treatment effect of this method mainly include pH value, ratio of medicament, ammonia nitrogen concentration, etc. Usually, the optimum pH value is 9~11. At this pH value, the removal rate of ammonia nitrogen in wastewater can reach 99%, but the chemical precipitation method needs The chemical precipitant is used in a large amount, and the pH of the wastewater needs to be controlled, so the management cost is high.

The stripping method is a method in which wastewater is brought into contact with air to transfer ammonia nitrogen from the liquid phase to the gas phase. Stripping is the contact of water as a discontinuous phase with air. The difference between the actual concentration of the components in the water and the equilibrium concentration is used to transfer ammonia nitrogen to the gas phase to remove ammonia nitrogen from the wastewater, usually with ammonium ions (NH4+) and free. The state of ammonia (NH3) exists in balance. When the pH of the wastewater is adjusted to be alkaline, the ionic ammonium is converted to molecular ammonia, and then the ammonia is blown out by air. The removal rate of ammonia nitrogen is about 50%~80%, the process is simple, and the treatment effect is stable. Now many blow-off devices are tested. Considering the economy, no ammonia is recovered and it is directly discharged into the atmosphere, causing air pollution.

The stripping method converts the free ammonia in the wastewater into ammonia gas by steam. The treatment mechanism is similar to the stripping method, that is, the wastewater is in close contact with the steam at a high pH value, thereby reducing the ammonia concentration in the wastewater. the process of. Extending the contact time between gas and liquid and the tightness of contact can improve the treatment efficiency of ammonia nitrogen. The packed tower can meet this requirement. The packing or filling of the tower can increase the infiltration surface area and form small water droplets or form a film to increase the contact between gas and liquid. Time, the stripping method can obtain a higher ammonia nitrogen removal effect than the stripping method, and the removal rate of ammonia nitrogen can reach over 97%. However, since the stripping method uses steam, it is easy to generate scale, the operation cannot be performed normally, and the operation and maintenance cost is also high.

However, the ammonia nitrogen removal rate of the conventional ammonia nitrogen wastewater treatment system still has room for further improvement. In view of this, the present invention provides an ammonia nitrogen wastewater treatment system through which the ammonia nitrogen removal rate can be increased and further removed. Ammonia gas is recycled into a chemical raw material with reusable value.

The ammonia nitrogen wastewater treatment system of the present invention comprises a water collection tank, an electroosmotic reactor, a stripping tower and a recovery tower.

The water collecting tank of the present invention is for accommodating wastewater containing ammonia nitrogen, and the electroosmotic reactor is connected to the sump for separating the wastewater containing ammonia nitrogen into concentrated water and the first diluted water by electroosmosis, wherein the first rare water The water is returned to the electroosmotic reactor and treated again by electroosmosis.

The stripping tower of the present invention comprises a spraying device and a blower. The spraying device is located at the top of the stripping tower for spraying the concentrated water produced by the electroosmotic reactor into the stripping tower, and the blower is located at the bottom of the stripping tower for introducing air into the stripping tower, wherein The concentrated water is blown off by the air to form ammonia gas and second diluted water. The ammonia gas blown out of the stripping tower will enter the bottom of the recovery tower to recover the ammonia gas after treatment.

The ammonia nitrogen wastewater treatment system provided by the present invention first separates the wastewater into concentrated water and the first diluted water through the electroosmotic reactor before the wastewater containing ammonia nitrogen is blown off, and then blows off the concentrated water, thereby greatly improving Ammonia nitrogen removal rate.

The conventional technique directly uses the blow-off method to have an ammonia nitrogen removal rate of 50% to 80%, and the present invention combines the electro-osmosis method with the blow-off method to achieve an ammonia nitrogen removal rate of 95% or more. The steps of the creation are simple, no need to add chemicals, are not affected by temperature, and can treat high concentration ammonia nitrogen wastewater, stable operation and low equipment maintenance cost, which greatly contributes to waste water recovery project.

The reason is that this creation is to study the above problems. After a long period of design and development, the “Ammonia Nitrogen Wastewater Treatment System” of this case was completed to solve the problem that the conventional ammonia nitrogen wastewater treatment method failed to achieve.

10‧‧‧Ammonia nitrogen wastewater treatment system

110‧‧‧ sink

111‧‧‧PH detector

112‧‧‧

120‧‧‧ Pipe Mixer

140‧‧‧Electro-osmotic reactor

150‧‧‧Blowing Tower

151‧‧‧First spraying device

152‧‧‧Blowers

153‧‧‧First packing layer

160‧‧‧Recycling tower

161‧‧‧Cold circulation device

162‧‧‧Second spraying device

163‧‧‧Recycling tank

164‧‧‧Second concentration tester

165‧‧" collection pool

166‧‧‧Second packing layer

170‧‧‧Drainage system

171‧‧‧First concentration tester

Directions D1, D2, D3, D4‧‧

The first picture, a schematic diagram of the ammonia nitrogen wastewater treatment system of the present creation.

In order to fully understand the efficacy of this creation, please refer to the diagram and figure number for a better example of this creation. Please refer to the first figure for the details. The ammonia nitrogen wastewater treatment system 10 of the present invention comprises a water collection tank 110, a pipeline mixer 120, an electroosmotic reactor 140, a stripping tower 150 and a recovery tower 160.

The sump 110 of the present invention is for accommodating waste water containing ammonia nitrogen, and the sump 110 has a pH detector 111, and the pH detector 111 is used for measuring the pH value of the wastewater, which is not limited thereto.

The electroosmotic reactor 140 is composed of a separator, an anion exchange membrane, a cation exchange membrane, an electrode and a clamping device, and the concentrated water containing the cationic NH4+ is separated from the diluted water containing the anion OH- by electroosmosis, and the electroosmosis method is used. It is a membrane separation technology. When the wastewater containing ammonia nitrogen passes through the electroosmotic reactor 140, the selective permeability of the ion exchange membrane is utilized by the applied DC electric field, and the anion OH- enters the lean water side through the anion exchange membrane, and the cation NH4+ The cation exchange membrane enters the concentrated water side, and the end is concentrated to be separated from the raw wastewater, and the concentrated water and the dilute water are defined by the concentration of NH4+ in the water.

The electroosmotic reactor 140 of the present invention is connected to the sump 110 for separating the wastewater containing ammonia nitrogen into concentrated water and the first diluted water by electroosmosis, wherein the first diluted water flows back to the electricity in the direction of D1. The permeation reactor 140 is again treated by electroosmosis.

A pipe mixer 120 is disposed between the sump 110 and the electroosmotic reactor 140. After the pH detector 111 measures the pH value of the wastewater, the user can add an acid or alkali catalyst to the pipeline mixer 120, such as sulfuric acid, hydrochloric acid or nitric acid, and alkali catalyst such as quicklime or sodium hydroxide. Potassium hydroxide to adjust the pH of the wastewater to avoid damage to the ion exchange membrane inside the electroporation reactor 140, which is not limited in this case.

Depending on the water pressure at each position in the system, a pump may be added to increase the flow rate of the water. In one embodiment, a pump 112 is disposed between the sump 110 of the present creation and the pipe mixer 120. The pump 112 It is used to assist the introduction of wastewater containing ammonia nitrogen into the electroosmotic reactor 140, which is not limited thereto.

Referring to the first figure, the stripping tower 150 of the present invention includes a first spraying device 151 and a blower 152. The first spraying device 151 is located at the top of the blowing tower 150, and the first spraying device 151 is composed of a plurality of nozzles, which is not limited thereto.

The concentrated water generated by the electroosmotic reactor 140 is introduced into the stripping tower 150 via the direction D2. The first spraying device 151 sprinkles the concentrated water produced by the electroosmotic reactor 140 into the stripping tower 150, and the blower 152 is located in the stripping tower 150. The bottom of the tower 150 is for introducing air into the stripping tower 150, and the concentrated water is blown off by the air to form ammonia gas and second rare water.

In addition, the stripping tower 150 is provided with a first filler layer 153, which may be a Raschig ring, a polypropylene Pall ring, a polypropylene multi-faceted hollow sphere or a combination thereof, which is not limited thereto. The first filler layer 153 is used to increase the area of the gas/liquid action, that is, the air blower 152 introduces air into the concentrated water, and the first filler layer 135 can make the gas and liquid sufficiently contact each other to dissolve the dissolved water. Ammonia passes through the gas-liquid interface and is transferred to the gas phase to achieve the purpose of removing ammonia nitrogen.

The stripping tower 150 is connected to a drainage system 170 for discharging the second diluted water. A first concentration detector 171 can be disposed between the stripping tower 150 and the drainage system 170. The present invention is not limited thereto, and the first concentration is detected. The meter 171 is used to detect the concentration of the second diluted water.

When the second diluted water that blows off the ammonia gas in the stripping tower 150 is discharged along the direction D3, the first concentration detector 171 is first used for concentration detection, and if the concentration of the second diluted water is higher than a standard value, The second diluted water will flow back to the electroosmotic reactor 140 from the pipeline to perform the electro-osmosis treatment again. If the concentration of the second lean water is lower than the standard value, it may be discharged to the drainage system 170, and the standard value may be According to the regulations of the current management authority, in a preferred embodiment, the standard value is 75. Mg/L, this case is not limited to this.

Referring to the first figure, the ammonia gas blown out in the stripping tower 150 will enter the bottom of the recovery tower 160 along the direction D4. The recovery tower 160 of the present invention is used to treat the ammonia gas and recover it. The tower 160 includes a cold cycle unit 161, a second spray unit 162, and a recovery tank 163. The second spraying device 162 is located at the top of the recycling tower 160, and the second spraying device 162 is composed of a plurality of nozzles, which is not limited thereto. .

In one embodiment, the cold circulation device 161 provides an adsorption liquid, and the cold circulation device 161 introduces the adsorption liquid into the top of the recovery tower 160, and the second spray device 162 sprays the adsorption liquid into the recovery tower 160 to make the adsorption liquid. Reacting with ammonia gas to obtain a recyclable product, the recyclable product will enter the recovery tank 163 via a pipeline, and the recovery tank 163 has a second concentration detector 164 for detecting the concentration of the recyclable product. This is limited to this.

When the second concentration detector 164 detects that the concentration of the recyclable product is below a recovery reference value, the recyclable product will be returned to the top of the recovery column 160 via the circulation pipe, and the recyclable product is sprinkled by the second spraying device 162. Into the recovery tower 160, and react with ammonia gas until the concentration of the recyclable product is greater than or equal to the recovery reference value, and then collect, the recovery tank 162 is connected to a collection tank 165, and the collection tank 165 is used for accommodating Recyclable products that meet the concentration of the recovery reference value are not limited to this case.

In one embodiment, the adsorbed liquid is water, sulfuric acid or phosphoric acid, such as water at 5 ° C to 8 ° C (preferably 5 ° C), dilute sulfuric acid or dilute phosphoric acid, which is not limited thereto. If the adsorbed liquid is water, the recoverable product is ammonia water (ammonium hydroxide, NH4OH), and the reference value of ammonia water recovery is 26%~32%; if the adsorbed liquid is dilute sulfuric acid, the recoverable product is ammonium sulfate (NH4) 2SO4, ammonium sulfate recovery reference concentration is 26%; if the adsorption liquid is dilute phosphoric acid, the recoverable product is ammonium phosphate (NH4) 2HPO4, ammonium sulfate recovery reference concentration is 38%, this case is not limited to this. Among them, ammonium sulfate and ammonium phosphate can be reused as raw materials for fertilizers, and this case is not limited thereto.

In addition, the recovery tower 160 is provided with a second filler layer 166, which may be a Raschig ring, a polypropylene Pall ring, a polypropylene multi-faceted hollow sphere or a combination thereof, which is not limited thereto. The second filler layer 166 is similarly used to increase the area of gas/liquid interaction.

The ammonia nitrogen wastewater treatment system provided by the present invention first separates the wastewater into concentrated water and first diluted water through the electroosmotic reactor 140 before the wastewater containing ammonia nitrogen is blown off. After that, the concentrated water is blown off, which greatly increases the ammonia nitrogen removal rate. The conventional technique directly uses the blow-off method to have an ammonia nitrogen removal rate of 50% to 80%, and the present invention combines the electro-osmosis method with the blow-off method to achieve an ammonia nitrogen removal rate of 95% or more. It is simple, no need to add chemicals, is not affected by temperature, and can treat high concentration of ammonia nitrogen wastewater. It is stable in operation and low in equipment maintenance cost, which provides great benefits for wastewater recycling projects.

The above embodiments are merely illustrative of the principles and functions of the present invention and are not intended to limit the present invention. Therefore, those skilled in the art can make modifications and changes to the above embodiments without departing from the spirit of the present invention. The scope of the rights of this creation shall be as set forth in the scope of the patent application described later.

10‧‧‧Ammonia nitrogen wastewater treatment system

110‧‧‧ sink

111‧‧‧PH detector

112‧‧‧

120‧‧‧ Pipe Mixer

140‧‧‧Electro-osmotic reactor

150‧‧‧Blowing Tower

151‧‧‧First spraying device

152‧‧‧Blowers

153‧‧‧First packing layer

160‧‧‧Recycling tower

161‧‧‧Cold circulation device

162‧‧‧Second spraying device

163‧‧‧Recycling tank

164‧‧‧Second concentration tester

165‧‧" collection pool

166‧‧‧Second packing layer

170‧‧‧Drainage system

171‧‧‧First concentration tester

Directions D1, D2, D3, D4‧‧

Claims (16)

An ammonia nitrogen wastewater treatment system comprising: a collecting tank for containing wastewater containing ammonia nitrogen; and an electroosmotic reactor connected to the collecting tank for separating the wastewater containing ammonia nitrogen into concentrated water by electroosmosis and first Dilute water, the first diluted water is returned to the electroosmotic reactor and treated by electroosmosis again; a stripping tower comprises: a first spraying device located at the top of the stripping tower for sprinkling the concentrated water a blower tower; and a blower located at the bottom of the stripping tower for introducing air into the stripping tower, through which the concentrated water is blown off to form ammonia gas and second diluted water; A recovery tower for recovering the ammonia gas after treatment. The ammonia nitrogen wastewater treatment system of claim 1, wherein the stripping tower is connected to a drainage system for discharging the second lean water. The ammonia nitrogen wastewater treatment system of claim 2, wherein a first concentration detector is disposed between the stripping tower and the drainage system for detecting the concentration of the second diluted water. The ammonia nitrogen wastewater treatment system of claim 1, wherein the sump has a pH detector. The ammonia nitrogen wastewater treatment system of claim 1, wherein a pipe mixer is disposed between the water collection tank and the electroosmotic reactor. The ammonia nitrogen wastewater treatment system according to claim 1, wherein the electroosmotic reactor comprises a separator, an anion-cation exchange membrane, a cation exchange membrane, an electrode, and a clamping device. The ammonia nitrogen wastewater treatment system according to claim 1, wherein the stripping tower is provided with a first packing layer, the first packing layer is a Raschig ring, a polypropylene Pall ring, a polypropylene multi-faceted hollow sphere or the above The combination of these. The ammonia nitrogen wastewater treatment system of claim 1, wherein the first spray device is composed of a plurality of spray heads. The ammonia nitrogen wastewater treatment system of claim 1, wherein the recovery column comprises a cold cycle device that provides an adsorption liquid that reacts with the ammonia gas to obtain a recyclable product. The ammonia nitrogen wastewater treatment system of claim 9, wherein the recovery column comprises a recovery tank for containing the recyclable product. The ammonia nitrogen wastewater treatment system of claim 10, wherein the recovery tank has a second concentration detector for detecting the concentration of the recyclable product. The ammonia nitrogen wastewater treatment system of claim 9, wherein the recovery tower further comprises a second spraying device located at the top of the recovery tower for spraying the adsorbed liquid into the recovery tower. The ammonia nitrogen wastewater treatment system of claim 12, wherein the second spray device is comprised of a plurality of spray heads. The ammonia nitrogen wastewater treatment system according to claim 1, wherein the recovery tower is provided with a second filler layer composed of a Raschig ring, a polypropylene Pall ring, a polypropylene multi-faceted hollow sphere or a combination thereof. . The ammonia nitrogen wastewater treatment system according to claim 9, wherein the adsorption liquid is water, sulfuric acid or phosphoric acid. The ammonia nitrogen wastewater treatment system of claim 15, wherein the temperature of the water ranges from 5 ° C to 8 ° C.