TW201305063A - Processing method for collecting waste water containing ammonia and apparatus thereof - Google Patents

Abstract

A processing method for collecting waste water containing ammonia comprises adding an acid solvent into a waste water containing ammonia to form an acid waste water, separating the acid waste water into a high and a low concentration waste water by a reverse osmosis membrane, and separating the high concentration waste water into waste water respectively containing anions and cations, so as to collect the waste water containing cations. The present invention further provides a processing apparatus for collecting waste water containing ammonia. After the acid waste water formed in a pH adjusting tank is separated into the high and the low concentration waste water by the reverse osmosis membrane, the high concentration waste water is further separated into the waste water respectively containing anions and cations in an ionization tank, so as to collect the waste water containing cations in a collecting tank.

Description

Ammonia wastewater recycling treatment method and equipment thereof

The invention relates to a method for recovering waste water and a device thereof, and particularly relates to a method for recycling and treating ammonia-containing wastewater and an apparatus therefor.

With the gradual increase of climate, the chances of disasters and droughts in the world have gradually increased, which has made it increasingly difficult to effectively preserve and utilize the clean water resources that are indispensable for human survival. More importantly, the rapid growth of the global population and the rapid development of industrial technology have led to the increasing environmental pollution of human beings and the worsening of the problem of water conservation and utilization. Therefore, how to effectively recover pollutants in industrial waste water to reduce the pollution of pollutants to the environment has gradually become one of the problems that governments around the world need to solve urgently.

Special wastewater containing high concentrations of ammonia (ammonia, chemical formula NH ₃ , commonly known as ammonia or anhydrous ammonia) is commonly found in optoelectronic semiconductor, petroleum refining, coking, and fertilizer. Industrial process wastewater such as (fertilizer), iron (iron and steel) and food (foodstuff). High-concentration ammonia has corrosiveness, is toxic to aquatic organisms, and has carcinogenicity and mutagenic properties to humans. Therefore, some countries have already enacted legislation or are inclined to legislate to limit the nitrogen content in wastewater.

Currently, the biological anaerobic treatment process is used to denitrify the ammonia-containing wastewater. However, the denitrification efficiency of the conventional biological anaerobic treatment process is not high. Therefore, there is an urgent need to provide an apparatus and method that can more effectively treat ammonia-containing wastewater.

In order to solve the above problems, the present invention provides a method for recovering ammonia-containing wastewater and a recycling treatment device for ammonia-containing wastewater to improve recovery efficiency of ammonia-containing wastewater.

The invention provides a method for recycling ammonia-containing wastewater, which comprises the following steps. First, an acid solvent is added to an ammonia-containing wastewater to form an acid waste water. Then, a reverse osmosis membrane (RO membrane) is used to separate the acidic wastewater into a high concentration wastewater and a low concentration wastewater. Then, the high-concentration wastewater is separated into an anions-containing wastewater and a cation-containing wastewater to recover the cationic wastewater.

In an embodiment of the invention, the ammonia-containing wastewater component further comprises hydrogen peroxide (chemical formula H ₂ O ₂ , commonly known as hydrogen peroxide), and further includes before adding the acidic solvent to the ammonia-containing wastewater. The hydrogen peroxide in the ammonia-containing wastewater is removed using a catalyst. The catalyst may be activated carbon fibers (ACF), manganese dioxide (manufactured by MnO ₂ ) or manganese ore (manganese ore).

In an embodiment of the invention, the high-concentration wastewater is separated into an anion-containing wastewater and a cationic wastewater by using an electrodialysis module or an ion exchange resin.

The invention further provides a recovery treatment device for ammonia-containing wastewater, which comprises a pH adjusting tank, a reverse osmosis membrane, an ionization tank and a collecting tank, wherein the reverse The permeable membrane is disposed between the pH adjustment tank and the dissociation tank, and the recovery tank is in communication with the dissociation tank. The pH adjustment tank is for containing an ammonia-containing wastewater, and is suitable for injecting an acidic solvent to form an acidic wastewater into the ammonia-containing wastewater. The reverse osmosis membrane is used to separate the acidic wastewater into a high concentration wastewater and a low concentration wastewater. The dissociation tank is used to separate the high concentration wastewater into an anionic wastewater and a cationic wastewater. The recovery tank is used to recover cationic wastewater.

In an embodiment of the present invention, the ammonia-containing wastewater recovery treatment device further includes a catalyst, and the ammonia-containing wastewater component further comprises hydrogen peroxide, and the pH-adjusting tank is disposed on the catalyst and the reverse osmosis membrane. between. Further, the catalyst is used to remove hydrogen peroxide in the ammonia-containing wastewater before the acidic solvent is injected into the ammonia-containing wastewater. Among them, the catalyst is activated carbon, manganese dioxide or iron manganese sand.

In an embodiment of the invention, the dissociation tank has an electrodialysis module or an ion exchange resin, and the high concentration wastewater is separated into an anion-containing wastewater and a cationic wastewater by using an electrodialysis module or an ion exchange resin. .

In an embodiment of the invention, the dissociation tank is connected to the pH adjustment tank for injecting the anion-containing wastewater as an acidic solvent into the pH adjustment tank.

In an embodiment of the invention, the ammonia-containing wastewater recovery processing apparatus further includes a storage tank. The storage tank is connected to the pH adjustment tank for storing the acidic solvent, and is suitable for injecting the acidic solvent into the pH adjustment tank.

In an embodiment of the invention, the acidic wastewater has a pH of less than 6.5.

In an embodiment of the present invention, the above-mentioned ammoniacal waste water, an acidic solvent with the component containing the anionic waste water are contained sulfate ions (sulfate ion, the formula SO ₄ ^2-) and chloride ions (chlorine ion, the formula Cl ^- ) at least one of them.

In an embodiment of the invention, the ammonia-containing wastewater component further comprises at least one of sodium ion (chemical formula Na ⁺ ) and ammonium ion (chemical ion NH ₄ ⁺ ).

Compared with the prior art, the present invention has a high efficiency in recovering ammonia in wastewater.

The above described features and advantages of the invention will be apparent from the following description.

1 is a flow chart showing a method of recycling ammonia-containing wastewater according to an embodiment of the present invention. Referring to FIG. 1, the recovery treatment method of the ammonia-containing wastewater includes the following steps. First, as shown in step S110, an acidic solvent is added to an ammonia-containing wastewater to adjust the pH of the originally alkaline ammonia-containing wastewater to less than 6.5 to form an acidic wastewater. Next, as shown in step S120, the reverse osmosis membrane is used to separate the acidic wastewater into a high concentration wastewater and a low concentration wastewater. Then, as shown in step S130, the high-concentration wastewater is dissociated to separate the high-concentration wastewater into an anion-containing wastewater and a cation-containing wastewater containing ammonia. As a result, as shown in step S140, the ammonia-containing cationic wastewater can be recovered.

In more detail, ammonia may be present in the solution as a positively charged ammonium ion (NH ⁴⁺ ). Since the acidic liquid will positively charge the reverse osmosis membrane, it will facilitate the reverse osmosis membrane to repel the positively charged ammonium ions, thereby retaining more ammonium ions in the high concentration wastewater. Therefore, in this embodiment, step S110 is first performed to adjust the originally alkaline ammonia-containing wastewater to acidic wastewater by an acidic solvent. Next, in step S120, when the acidic wastewater is separated into high-concentration wastewater and low-concentration wastewater by the reverse osmosis membrane, the ammonium ion content in the high-concentration wastewater can be increased. At this time, the low-concentration wastewater with extremely low ammonium ion content can be recycled or reused, or discharged to a wastewater treatment plant for subsequent general wastewater treatment processes.

Then, as shown in step S130, an electrodialysis module or an ion exchange resin is used to dissociate the high-concentration wastewater to separate the high-concentration wastewater into an anion-containing wastewater and a cationic wastewater. Then, the ammonia-containing cationic wastewater can be recovered as shown in step S140. Compared with the prior art, the ammonia-containing wastewater is denitrified by a biological anaerobic process. This embodiment treats the ammonia-containing wastewater by first concentrating and dissociating, and has a high ammonia recovery efficiency.

It is worth noting that in order to simplify the subsequent treatment of low-concentration wastewater, anion-containing wastewater, and by-products including cationic wastewater in the above process, the anion component contained in the acidic solvent is preferably mainly contained in the ammonia-containing wastewater. The anionic components are the same to avoid the main components of the above by-products being too complicated.

More specifically, the main components of ammonia-containing wastewater from the semiconductor industry or other industries usually do not contain only ammonium ions, and may also contain sulfate ions or anions such as chloride ions. For example, the main component of the ammonia-containing wastewater may be ammonium sulphate (chemical formula (NH ₄ ) ₂ SO ₄ ) wastewater or ammonium chloride (chemical formula NH ₄ Cl) wastewater. In this case, the main component of the acidic solvent may be a sulfuric acid (chemical formula H ₂ SO ₄ ) solution or a hydrochloric acid (hydrochloric acid, chemical formula HCl, commonly known as hydrochloric acid) solution.

Further, when the main component of the ammonia-containing wastewater contains sulfate ions or chloride ions, at least one of the sulfate ion and the chloride ion may be contained in the main component of the anion-containing wastewater generated in the step S130. At this time, the anion-containing wastewater can be used as an acidic solvent for adjusting the pH value of the ammonia-containing wastewater for reuse.

In addition to this, in this embodiment, the component containing ammonia wastewater may further contain sodium ions. Therefore, in the recovery of the cation-containing wastewater, in addition to the recovery of ammonia, a sodium compound can be recovered together.

2 is a flow chart showing a method of recycling ammonia-containing wastewater according to another embodiment of the present invention. Referring to FIG. 2, the ammonia-containing wastewater recovery treatment method in this embodiment is similar to the ammonia-containing wastewater recovery treatment method in the previous embodiment, and the difference is in the ammonia-containing wastewater in this embodiment. The main component further contains hydrogen peroxide. Therefore, in step S110, before the acidic solvent is injected into the ammonia-containing wastewater to form the acidic wastewater, the step S100 is further included to remove the hydrogen peroxide in the ammonia-containing wastewater by using a catalyst. Among them, the catalyst may be activated carbon, manganese dioxide or iron manganese sand. The other steps are the same as in the previous embodiment, and are not described herein again.

In order to make it easier for those skilled in the art to understand the above-mentioned ammonia-containing wastewater recovery treatment method. Hereinafter, a recycling treatment apparatus for ammonia-containing wastewater will be further disclosed by a specific embodiment. However, the above-mentioned ammonia-containing wastewater recovery treatment method cannot be carried out only by using the following ammonia-containing wastewater recovery treatment equipment.

3 is a schematic view showing the structure of a recycling treatment apparatus for ammonia-containing wastewater according to an embodiment of the present invention. Referring to FIG. 3, the ammonia-containing wastewater recovery processing apparatus 100a includes a pH adjustment tank 110, a reverse osmosis membrane 120, a dissociation tank 130, and a recovery tank 140. The reverse osmosis membrane 120 is disposed between the pH adjustment tank 110 and the dissociation tank 130 , and the recovery tank 140 is in communication with the dissociation tank 130 .

The pH adjusting tank 110 is for accommodating ammonia-containing wastewater, and is suitable for injecting an acidic solvent to adjust the originally alkaline ammonia-containing wastewater to acidic wastewater. Then, the reverse osmosis membrane 120 is used to separate the acidic wastewater into high-concentration wastewater and low-concentration wastewater. Among them, low-concentration wastewater with extremely low ammonia content can be recycled or reused, or discharged to a wastewater treatment plant for subsequent general wastewater treatment process, and high-concentration wastewater with extremely high ammonia content is injected into the dissociation tank 130 to utilize dissociation. The electrodialysis module or ion exchange resin in the tank 130 is further separated into an anionic wastewater and a cationic wastewater. Thereafter, the cation-containing wastewater is injected into the recovery tank 140 for recovery. Similarly, the ammonia-containing wastewater is denitrified by a biological anaerobic process compared to the prior art. This embodiment treats the ammonia-containing wastewater by first concentrating and dissociating, and can have a high recovery efficiency.

In addition, when the main component of the ammonia-containing wastewater further contains an anion such as a sulfate ion or a chloride ion, a hydride of the above anion (such as sulfuric acid and hydrochloric acid) may be selected as a main component of the acidic solvent, so as to simplify the low. Subsequent processing operations for concentration wastewater, anion-containing wastewater, and by-products such as cationic wastewater. Moreover, in this embodiment, the dissociation groove 130 may also communicate with the pH adjustment groove 110. At this time, it is also possible to directly inject the anion-containing wastewater as an acidic solvent for adjusting the pH value of the ammonia-containing wastewater, and inject it into the pH adjustment tank 110 for reuse.

It is worth noting that some of the anions will be discharged with the low concentration of wastewater in the above process, so the anion content in the anion-containing wastewater may not be sufficient to adjust the ammonia-containing wastewater to the desired pH in the subsequent process. Therefore, the ammonia-containing wastewater recovery treatment apparatus 100a in this embodiment may further include a storage tank 150 connected to the pH adjustment tank 110 and used to store the acidic solvent, so as to remove the acidic solvent from the storage tank 150 according to the demand. It is injected into the pH adjustment tank 110.

Further, the ammonia treatment wastewater recovery treatment apparatus 100a may further include a plurality of pumps 160, 170, and 180. The pump 160 may be connected between the pH adjustment tank 110 and the reverse osmosis membrane 120 for transporting the acidic wastewater from the pH adjustment tank 110 to the reverse osmosis membrane 120. Furthermore, the pump 170 can be connected between the reverse osmosis membrane 120 and the dissociation tank 130 for injecting high concentration wastewater from the reverse osmosis membrane 120 into the dissociation tank 130. In addition, the pump 180 may be connected between the storage tank 150 and the pH adjustment tank 110 for injecting the acidic solvent from the storage tank 150 into the pH adjustment tank 110.

In addition to this, in this embodiment, the component containing ammonia wastewater may further contain sodium ions. Therefore, in the recovery of the cation-containing wastewater, in addition to the recovery of ammonia, the sodium compound can be recovered together.

4 is a schematic view showing the structure of a recycling treatment apparatus for ammonia-containing wastewater according to another embodiment of the present invention. Referring to FIG. 4, the ammonia-containing wastewater recovery treatment device 100b in this embodiment is similar to the ammonia-containing wastewater recovery treatment device 100a in the previous embodiment, and the difference is in the ammonia content in this embodiment. The main component of the wastewater further contains hydrogen peroxide. Therefore, the ammonia treatment wastewater recovery apparatus 100b may further include a catalyst 190, and the pH adjustment tank 110 is disposed between the catalyst 190 and the reverse osmosis membrane 120. The catalyst 190 may be activated carbon, manganese dioxide or iron manganese sand for removing hydrogen peroxide in the acidic wastewater before injecting the acidic solvent into the ammonia-containing wastewater. The functions and connection relationships of other components are the same as those of the previous embodiment, and will not be described herein.

In summary, since the acidic liquid causes the reverse osmosis membrane to be positively charged, it is advantageous for the reverse osmosis membrane to repel the ammonium ion to retain more ammonium ions in the high concentration wastewater. Therefore, the present invention first adjusts the acidity and alkalinity of the ammonia-containing wastewater to be acidic, and then, when the acidic wastewater is separated into high-concentration wastewater and low-concentration wastewater by using a reverse osmosis membrane, the recovery efficiency of the reverse ion membrane for the ammonium ion can be improved. . Then, the high-concentration wastewater is treated to separate it into an anionic wastewater and a cationic wastewater. After that, the cationic wastewater containing ammonia can be recovered. Therefore, the present invention is more efficient in recovering ammonia than the prior art.

Although the present invention has been disclosed in the above embodiments, it is not intended to limit the present invention, and those skilled in the art can make some modifications and refinements without departing from the spirit and scope of the present invention. The scope of the invention is defined by the scope of the appended claims.

100a, 100b. . . Recycling equipment for ammonia-containing wastewater

110. . . pH adjustment tank

120. . . Reverse osmosis membrane

130. . . Dissociation slot

140. . . Recovery tank

150. . . Storage tank

160, 170, 180. . . Pump

190. . . catalyst

S100, S110, S120, S130, S140. . . step

1 is a flow chart showing a method of recycling ammonia-containing wastewater according to an embodiment of the present invention.

2 is a flow chart showing a method of recycling ammonia-containing wastewater according to another embodiment of the present invention.

3 is a schematic view showing the structure of a recycling treatment apparatus for ammonia-containing wastewater according to an embodiment of the present invention.

4 is a schematic view showing the structure of a recycling treatment apparatus for ammonia-containing wastewater according to another embodiment of the present invention.

S110, S120, S130, S140. . . step

Claims (16)

An ammonia-containing wastewater recycling treatment method comprises: adding an acidic solvent to an ammonia-containing wastewater to form an acidic wastewater; and separating the acidic wastewater into a high-concentration wastewater and a low-concentration wastewater by using a reverse osmosis membrane; The high-concentration wastewater is separated into an anion-containing wastewater and a cationic wastewater to recover the cationic wastewater. The method for recovering ammonia-containing wastewater according to claim 1, wherein the component of the ammonia-containing wastewater further comprises hydrogen peroxide, and before the acidic solvent is added to the ammonia-containing wastewater, the use of the touch The medium removes the hydrogen peroxide in the ammonia-containing wastewater. The method for recovering ammonia-containing wastewater according to claim 2, wherein the catalyst is activated carbon, manganese dioxide or iron manganese sand. The method for recovering ammonia-containing wastewater according to claim 1, wherein the acid wastewater has a pH of less than 6.5. The method for recovering ammonia-containing wastewater according to claim 1, wherein the high-concentration wastewater is separated into the anion-containing wastewater and the cationic wastewater by using an electrodialysis module or an ion exchange resin. The method for recovering ammonia-containing wastewater according to claim 1, wherein the ammonia-containing wastewater, the acidic solvent and the anion-containing wastewater comprise at least one of a sulfate ion and a chloride ion. The method for recovering ammonia-containing wastewater according to claim 1, wherein the component of the ammonia-containing wastewater further comprises at least one of sodium ions and ammonium ions. The invention relates to a recycling treatment device for ammonia-containing wastewater, comprising: a pH adjustment tank for accommodating an ammonia-containing wastewater, and suitable for injecting an acidic solvent to form an acidic wastewater into the ammonia-containing wastewater; a reverse osmosis membrane, The separation process is used to separate the acidic wastewater into a high concentration wastewater and a low concentration wastewater; a dissociation membrane, the reverse osmosis membrane is disposed between the pH adjustment tank and the dissociation tank, and the dissociation tank is used for the high The concentration wastewater is separated into an anion-containing wastewater and a cationic wastewater; and a recovery tank is connected to the dissociation tank for recovering the cationic wastewater. The recycling treatment device for ammonia-containing wastewater according to claim 8 further includes a catalyst, and the component of the ammonia-containing wastewater further comprises hydrogen peroxide, wherein the pH adjustment groove is disposed in the catalyst and The hydrogen peroxide in the ammonia-containing wastewater is removed between the reverse osmosis membranes and before the acidic solvent is injected into the ammonia-containing wastewater. The recycling treatment device for ammonia-containing wastewater according to claim 9, wherein the catalyst is activated carbon, manganese dioxide or iron manganese sand. The method for recovering ammonia-containing wastewater according to claim 8, wherein the acid wastewater has a pH of less than 6.5. The recycling treatment device for ammonia-containing wastewater according to claim 8, wherein the dissociation tank has an electrodialysis module or an ion exchange resin, and the high concentration wastewater utilizes the electrodialysis module or the The ion exchange resin is separated into the anion-containing wastewater and the cationic wastewater. The apparatus for recovering ammonia-containing wastewater according to claim 8, wherein the dissociation tank is connected to the pH adjustment tank for injecting the anion-containing wastewater as the acidic solvent into the pH adjustment tank. in. The apparatus for recycling ammonia-containing waste liquid according to claim 8 , further comprising a storage tank connected to the pH adjustment tank for storing the acidic solvent, and suitable for injecting the acidic solvent The pH value is adjusted in the tank. The apparatus for recycling ammonia-containing wastewater according to claim 8, wherein the ammonia-containing wastewater, the acidic solvent and the anion-containing wastewater comprise at least one of a sulfate ion and a chloride ion. The recycling treatment device for ammonia-containing wastewater according to claim 8, wherein the component of the ammonia-containing wastewater further comprises at least one of sodium ions and ammonium ions.