TW202313490A - Water treatment method and water treatment device - Google Patents

Abstract

An object of the invention is to provide a water treatment method and a water treatment device that are capable of recovering ammonia from an ammonia-containing water, and of further recovering valuable matter and water from the wastewater remaining after the removal of the recovered materials. The water treatment method for recovering valuable matter from an ammonia-containing water includes: a first recovery step of using a distillation device (11) to recover at least one of ammonia and ammonium ions from the ammonia-containing water as a first recovered material, and a second recovery step in which, using a semipermeable membrane module (10) having a first space (14) and a second space (16) separated by a semipermeable membrane (12), the distilled water from the distillation device (11) is passed into the first space (14) and the first space (14) is pressurized, causing the water in the distilled water to pass through the semipermeable membrane (12) thereby obtaining a second recovered material as a concentrate, and a portion of the distilled water or at least a portion of the concentrate is passed into the second space (16) to obtain a diluted water.

Description

Water treatment method and water treatment device

The invention relates to a water treatment method and a water treatment device for recovering valuables from ammonia-containing water.

In recent years, as a method of recovering valuables in wastewater from factories, etc., there are reverse osmosis methods that use reverse osmosis membranes to recover permeated water to reduce the volume of water, and membrane distillation methods that use gas permeable membranes. .

Also, we know a method, as described in Patent Document 1, by circulating the treated water or its concentrated water through the first space and the second space separated by the semipermeable membrane of the semipermeable membrane module, and the second A space is pressurized and the water is concentrated. In this way, the concentration method using a semi-permeable membrane, compared with the general reverse osmosis method, can reduce the concentration difference (osmotic pressure difference) between the first space and the second space, and concentrate the drainage to a high level with less energy consumption. concentration.

We also know a method, as described in Patent Document 2, in which ammonia is recovered as a gas from ammonia-containing water containing ammonia by a distillation device. In the case of using the method by the distillation method, a large amount of wastewater is generated after removal of ammonia, which is a recycled product. In addition, the concentration of dissolved solids (TDS) such as inorganic salts in the wastewater will increase, so the wastewater is not suitable for reuse. Therefore, the effluent from distillation is discharged directly or after further treatment.

Therefore, while recovering ammonia from ammonia-containing water, a method for further recovering and reusing valuables and water from the waste water after removal of recovered substances is sought. [Prior Art Literature] [Patent Document]

[Patent Document 1] Japanese Patent Laid-Open No. 2018-069198 [Patent Document 2] Japanese Patent Laid-Open No. 2019-098205

[Problem to be solved by the invention]

The object of the present invention is to provide a water treatment method and a water treatment device, which can recover valuables and water from the waste water after removal of recycled materials while recovering ammonia from ammonia-containing water. [Technical means to solve the problem]

The present invention relates to a water treatment method for recovering valuables from ammonia-containing water, comprising the following steps: a first recovery step, using a distillation device to obtain at least one of ammonia and ammonium ions from the ammonia-containing water as the first recovered product be recovered; and the second recovery step, by using a semi-permeable membrane module having a first space and a second space separated by a semi-permeable membrane, and circulating the distilled water of the distillation device to the first space, and The first space is pressurized so that the water contained in the distilled water permeates the semipermeable membrane to obtain the second recovered product as concentrated water, and at the same time, a part of the distilled water or a part of the concentrated water is passed through the second space. at least partly to obtain dilution water.

The present invention is a water treatment method for recovering valuables from ammonia-containing water, comprising the following steps: a first recovery step, using a distillation device to extract at least one of ammonia and ammonium ions from the ammonia-containing water as a first recovered product Recovery; the second recovery step, by using a semi-permeable membrane module connected by a plurality of sections with a first space separated by a semi-permeable membrane and a second space, and the first space of the first section of the semi-permeable membrane module Circulate the distilled water of the distillation device, and pressurize the first space so that the water contained in the distilled water permeates the semi-permeable membrane to obtain concentrated water, and then use the semi-permeable membrane module after the next stage to concentrate the water The water is further used as concentrated water to obtain the second recovered product, and at the same time, a part of the distilled water or at least a part of the concentrated water is passed through the second space of the semi-permeable membrane module of each section or obtained from other semi-permeable membranes. At least a part of the dilution water obtained by the module is used to obtain the dilution water.

The water treatment method preferably further comprises the following steps: a water recovery step, after the second recovery step, circulating at least a part of the dilution water discharged from the second recovery step to the reverse osmosis membrane to obtain permeate water; and sending return step, the concentrated water discharged from the reverse osmosis membrane is sent back to the front section of the semi-permeable membrane module.

In the water treatment method, the ammonia-containing water preferably has a sulfate ion concentration above 6000 mg/L and an ammonium ion concentration above 2000 mg/L.

The present invention is a water treatment device for recovering valuables from ammonia-containing water, comprising: a first recovery means, using a distillation device to recover at least one of ammonia and ammonium ions from the ammonia-containing water as a first recovered product; And the second recovery means, by using a semi-permeable membrane module having a first space and a second space separated by a semi-permeable membrane, and passing the distilled water of the distillation device through the first space, and pressurizing the The first space allows the water contained in the distilled water to permeate the semi-permeable membrane to obtain the second recovered product as concentrated water, and at the same time, a part of the distilled water or at least a part of the concentrated water flows through the second space, for dilution water.

The present invention is a water treatment device for recovering valuables from ammonia-containing water, comprising: a first recovery means, using a distillation device to recover at least one of ammonia and ammonium ions from the ammonia-containing water as a first recovered product; And the second recovery means, by using a semi-permeable membrane module connected in multiple sections with a first space and a second space separated by a semi-permeable membrane, and circulating through the first space of the first semi-permeable membrane module The distilled water of the distilling device is used to pressurize the first space so that the water contained in the distilled water permeates the semi-permeable membrane to obtain concentrated water, which is concentrated by using the semi-permeable membrane module after the next stage The water is further used as concentrated water to obtain the second recovered product, and at the same time, a part of the distilled water or at least a part of the concentrated water is passed through the second space of the semi-permeable membrane module of each section or obtained from other semi-permeable membranes. At least a part of the dilution water obtained by the module is obtained to obtain the dilution water.

In the water treatment device, it is preferable to further include: water recovery means, after the second recovery means, at least a part of the dilution water discharged from the second recovery means is circulated to the reverse osmosis membrane to obtain permeated water; And return means, send the concentrated water discharged from the reverse osmosis membrane back to the front section of the semi-permeable membrane module.

In the water treatment device, the ammonia-containing water preferably has a sulfate ion concentration above 6000 mg/L and an ammonium ion concentration above 2000 mg/L. [Invention effect]

According to the present invention, there are provided a water treatment method and a water treatment device, which can recover valuables and water from the waste water after removal of recycled materials while recovering ammonia from ammonia-containing water.

Embodiments of the present invention will be described below. This embodiment is an example of implementing the present invention, and the present invention is not limited to this embodiment.

FIG. 1 shows an outline of an example of a water treatment device according to an embodiment of the present invention, and describes its configuration.

The water treatment device 1 shown in FIG. 1 is a device for recovering valuables from ammonia-containing water. The water treatment device 1 includes: a distillation device 11 as a first recovery means, recovering at least one of ammonia and ammonium ions from ammonia-containing water as a first recovery product; and as a second recovery means, such as a membrane module 10 , using a semi-permeable membrane module having a first space (concentrating side) 14 and a second space (permeation side) 16 separated by a semi-permeable membrane 12, and the distilled water of the distillation device 11 is passed through the first space 14, The first space 14 is pressurized so that the water contained in the distilled water permeates the semipermeable membrane 12 to obtain the second recovered product as concentrated water, and at the same time, a part of the distilled water flows into the second space 16 to obtain dilution water. The water treatment device 1 may include a distilled water tank for storing distilled water between the distiller 11 and the membrane module 10 .

In the water treatment device 1 of FIG. 1 , a pipe 25 is connected to the inlet of the distillation device 11 . A pipe 27 is connected to the first recovered product outlet of the distillation apparatus 11 . The distilled water outlet of the distillation device 11 is connected to the first space inlet of the membrane module 10 through a pump 18 and connected by a pipe 24, and a pipe 26 branched from the pipe 24 on the downstream side of the pump 18 is connected to the pipe 26 through a valve 22. The second space inlet of the membrane module 10 is connected. A pipe 28 is connected to an outlet of the first space of the membrane module 10 via a valve 23 , and a pipe 30 is connected to an outlet of the second space of the membrane module 10 .

The pump 18 is, for example, a booster pump that is driven at a rotation speed corresponding to the input drive frequency, sucks in the distilled water, and discharges it toward the membrane module 10 under pressure. For example, an inverter 20 is provided in the pump 18 to output the drive frequency corresponding to the input command signal to the pump 18 . The valves 22 and 23 are, for example, valves whose opening and closing degrees can be adjusted manually or automatically.

The membrane module 10 is provided with a first space 14 and a second space 16 separated by a semi-permeable membrane 12, and by distilling water from the first space inlet of the membrane module 10 to the first space 14, from the second The space inlet communicates with the second space 16 and pressurizes the first space 14, so that the water contained in the distilled water in the first space 14 penetrates into the second space 16 through the semi-permeable membrane 12 to concentrate the water . That is, in the water treatment device 1 , the distilled water is concentrated using the semipermeable membrane 12 . The membrane module 10 is a device that supplies distilled water to both the first space 14 and the second space 16 of the membrane module 10 to perform concentration treatment.

In the water treatment device 1 , ammonia-containing water containing ammonia is supplied to the distillation device 11 through a pipe 25 . Distillation is performed in the distillation device 11 to recover at least one of ammonia and ammonium ions from the ammonia-containing water as a first recovery product (first recovery step). The first recyclate is discharged through the pipe 27 .

The distilled water obtained in the distillation device 11 is pressurized and sent to the first space 14 from the inlet of the first space of the membrane module 10 by the pump 18 through the piping 24 when the valve 23 is open. . In addition, the distilled water is fed from the second space inlet of the membrane module 10 through the pipe 26 branched from the pipe 24 when the valve 22 is open, and flows into the second space 16 . Part of the water contained in the pressurized distilled water permeates from the first space 14 to the second space 16 through the semipermeable membrane 12 . At this time, since most of the ions contained in the distilled water cannot permeate the semipermeable membrane 12, the water system in the first space 14 that does not permeate the semipermeable membrane 12 is concentrated. On the other hand, in the second space 16, since a part of the distilled water flowing through the pipe 26 merges with the permeated water having a low ion concentration permeating the semipermeable membrane 12, a dilution effect occurs. The concentrated water obtained in the first space 14 is discharged from the outlet of the first space through the pipe 28 as the second recovery product, and the dilution water obtained in the second space 16 is discharged from the outlet of the second space through the pipe 30 . Here, in the membrane module 10, the first space 14 is pressurized so that the water contained in the distilled water in the first space 14 permeates into the second space 16 through the semi-permeable membrane 12, so that the first space 14 Concentrated water (second recovery) is obtained (concentration step), while dilution water is obtained in the second space 16 (dilution step) (the above is the second recovery step).

Here, the pipes 24 , 26 , the pump 18 and the like function as supply means for supplying distilled water to both the first space 14 and the second space 16 of the membrane module 10 .

The dilution water obtained in the second space 16 can be discharged out of the system through the pipe 30, or sent to the dilution water tank for storage as required, and then discharged out of the system or reused. At least a part of the dilution water may be sent to the distillation treatment water tank and mixed with the distillation treatment water in the distillation treatment water tank. About at least a part of dilution water, you may further perform other processing, for example, perform reverse osmosis membrane processing as mentioned later.

As described above, at least one of ammonia and ammonium ions is recovered from ammonia-containing water containing ammonia as the treatment object, and at least one of ammonia and ammonium ions is recovered as the first recovered product, and the concentrated water after the ions are concentrated is recovered as the second recovered product. The material is recovered to obtain dilution water for volume reduction of ammonia-containing water. In addition, the first recovered material, the second recovered material, and the dilution water can be reused.

By passing the distilled water through the first space 14 and the second space 16 of the membrane module 10, the osmotic pressure difference between the first space 14 side and the second space 16 side of the semipermeable membrane 12 can be reduced, and the Concentrate the high-concentration ions in the distilled water by consuming less energy. That is, the distilled water containing ions at a high concentration can be concentrated at low cost, and the amount of waste liquid having a high ion concentration can be reduced.

As an adjustment method for adjusting "the supply flow rate of distilled water supplied to the membrane module 10, the flow rate of permeate water, and the flow rate of concentrated water", for example, the following method is preferably performed.

The pump 18 is provided with an inverter 20 that controls the driving frequency to adjust the supply flow rate of the distilled water supplied to the membrane module 10 . Although it is preferable to provide the inverter 20 in the pump 18, it may not be provided. As long as the distilled water is supplied to both sides of the first space 14 side and the second space 16 side, and a valve 22 is provided before the entrance of the second space 16, and a valve 23 is provided at the exit of the first space 14, by manual or The opening degrees of the valves 22 and 23 are adjusted automatically, and the ratio of the flow rate of water supplied to the first space 14 side to the flow rate of water supplied to the second space 16 side may be adjusted.

When the permeate water flow rate and the concentrated water flow rate are insufficient, the frequency of the inverter 20 of the pump 18 may be raised to increase the supply of distilled water.

At the outlet of the first space 14 of the piping 28, a valve 23 with an adjustable opening and closing degree is provided, and the flow rate of the concentrated water and the pressure of the inlet of the first space 14 and the outlet of the first space 14 can be adjusted by the opening of the valve 23 .

Through these operations, the pressure and various flow rates on the predetermined first space 14 side can be adjusted.

Also, the supply of the distilled water to the first space 14 side and to the second space 16 side may be performed by separate pumps. In the case where the distilled water is supplied by separate pumps, an inverter for controlling the drive frequency may be provided for each pump.

The osmotic pressure generated by the semi-permeable membrane 12 can be reduced and the necessary pressure can be lowered by passing distilled water with the same or similar concentration to both sides of the first space 14 and the second space 16 . As a result, "distilled water at a concentration that cannot be concentrated by the conventional reverse osmosis membrane method" can be concentrated.

In this way, while ammonia is recovered from the ammonia-containing water, valuables and water can be further recovered from the distilled water after removal of recovered substances. While using distillation to recover ammonia from ammonia-containing water, the semi-permeable membrane module can be used to concentrate the distilled water at a high concentration, thereby increasing recyclables, reducing the amount of discharged water, and improving water recovery.

FIG. 2 shows an outline of another example of a water treatment device according to an embodiment of the present invention, and describes its configuration.

The water treatment device 2 shown in Fig. 2 comprises: a distillation device 11 as a first recovery means, from ammonia-containing water, at least one of ammonia and ammonium ions is recovered as a first recovery product; and as a second recovery means For example, the membrane module 10, by using a semi-permeable membrane module having a first space (concentrating side) 14 and a second space (permeation side) 16 separated by a semi-permeable membrane 12, the first space 14 is circulated and distilled The device 11 distills water, and pressurizes the first space 14 so that the water contained in the distilled water permeates the semi-permeable membrane 12 to obtain the second recovered product as concentrated water, and at the same time, at least a part of the concentrated water is passed through the second space 16 to obtain dilution water. The water treatment device 2 may include a distilled water tank storing distilled water between the distiller 11 and the membrane module 10 .

In the water treatment device 2 shown in FIG. 2 , a pipe 25 is connected to the inlet of the distillation device 11 . A pipe 27 is connected to the first recovered product outlet of the distillation apparatus 11 . The outlet of the distilled water of the distillation device 11 and the inlet of the first space of the membrane module 10 are connected by a pipe 24 via a pump 18 . A pipe 28 is connected to the outlet of the first space of the membrane module 10 via a valve 23 . A pipe 34 branched from the pipe 28 on the upstream side of the valve 23 is connected to the second space inlet of the membrane module 10 via the valve 32 . A pipe 36 is connected to the outlet of the second space of the membrane module 10 .

The pump 18 is, for example, a booster pump that is driven at a rotational speed corresponding to the input drive frequency, sucks in distilled water, and discharges it toward the membrane module 10 under pressure. The pump 18 is provided with, for example, an inverter 20 that outputs a driving frequency corresponding to an input command signal to the pump 18 . The valves 23 and 32 are, for example, valves whose opening and closing degrees can be adjusted manually or automatically.

The membrane module 10 has a first space 14 and a second space 16 separated by a semi-permeable membrane 12, and the distilled water is circulated from the first space inlet of the membrane module 10 to the first space 14, and at the same time, the At least a part of the concentrated water discharged from the first space outlet of the first space 14 of the membrane module 10 circulates from the second space inlet of the membrane module 10 to the second space 16, and pressurizes the first space 14, so that The water contained in the distilled water in the first space 14 penetrates into the second space 16 through the semi-permeable membrane 12 to concentrate the water. That is, in the water treatment device 2 , the distilled water is concentrated using the semipermeable membrane 12 . The membrane module 10 supplies distilled water to the first space 14 of the membrane module 10, and at least a part of the concentrated water obtained from the outlet of the first space 14 is supplied to the second space 16 of the membrane module 10. Device for concentration treatment.

In the water treatment device 2 , ammonia-containing water containing ammonia is supplied to the distillation device 11 through a pipe 25 . Distillation is performed in the distillation apparatus 11, and at least one of ammonia and ammonium ions is recovered from the ammonia-containing water as a first recovery product (first recovery step). The first recyclate is discharged through the pipe 27 .

The distilled water obtained in the distillation device 11 is pressurized and sent to the first space 14 from the inlet of the first space of the membrane module 10 by the pump 18 through the piping 24 when the valve 23 is open. . Part of the water contained in the pressurized distilled water permeates from the first space 14 to the second space 16 through the semipermeable membrane 12 . At this time, since most of the ions and the like cannot permeate the semipermeable membrane 12, the water system in the first space 14 impermeable to the semipermeable membrane 12 is concentrated. On the other hand, in the second space 16, since "part of the concentrated water flowing through the pipe 34" and "the permeated water with a low ion concentration permeating the semipermeable membrane 12" flow together, a dilution effect occurs. The concentrated water obtained in the first space 14 is discharged from the outlet of the first space through the pipe 28 as the second recovered product, and at least a part of the concentrated water is passed through the pipe branched from the pipe 28 when the valve 32 is open. The pipe 34 is used to send liquid from the inlet of the second space of the membrane module 10 to flow into the second space 16 . The dilution water obtained in the second space 16 is discharged through the pipe 36 from the outlet of the second space. Here, in the membrane module 10, the first space 14 is pressurized so that the water contained in the distilled water in the first space 14 permeates into the second space 16 through the semipermeable membrane 12, so that the first space 14 Concentrated water (second recovery) is obtained (concentration step), while dilution water is obtained in the second space 16 (dilution step) (the above is the second recovery step).

Here, the piping 24, 28, 34, pump 18, etc. are used to supply distilled water to the first space 14 of the membrane module 10, and at least a part of the concentrated water obtained from the outlet of the first space 14 is supplied to the The second space 16 of the membrane module 10 functions as a supply means.

The dilution water obtained in the second space 16 can be discharged out of the system through the pipe 36, or can be sent to the dilution water tank for storage if necessary, and then discharged out of the system, or can be reused. At least a part of the dilution water may be sent to the distillation treatment water tank and mixed with the distillation treatment water in the distillation treatment water tank. About at least a part of dilution water, you may further perform other processing, for example, perform reverse osmosis membrane processing as mentioned later.

As described above, at least one of ammonia and ammonium ions is recovered from ammonia-containing water containing ammonia as the treatment object, and at least one of ammonia and ammonium ions is recovered as the first recovered product, and the concentrated water after the ions are concentrated is recovered as the second recovered product. The substance is recovered to obtain dilution water for volume reduction of ammonia-containing water. In addition, the first recovered material, the second recovered material, and the dilution water can be reused.

By passing the distilled water through the first space 14 of the membrane module 10 and at least a part of the concentrated water obtained in the first space 14 through the second space 16, the first space 14 side of the semipermeable membrane 12 can be reduced. The osmotic pressure difference from the side of the second space 16 is used to concentrate the high-concentration ions in the distilled water with less energy consumption. That is, the distilled water containing ions at a high concentration can be concentrated at low cost, and the amount of waste liquid with a high ion concentration can be reduced.

As an adjustment method for adjusting the supply flow rate of the distilled water supplied to the membrane module 10, the flow rate of the permeate water, and the flow rate of the concentrated water, for example, the following method is preferably performed.

The pump 18 is provided with an inverter 20 that controls the driving frequency to adjust the supply flow rate of the distilled water supplied to the membrane module 10 . It is preferable to install an inverter 20 in the pump 18, but it may not be installed. As long as the distilled water is supplied to the side of the first space 14, a valve 23 is installed at the outlet of the first space 14, a valve 32 is installed before the entrance of the second space 16, and the valve is adjusted manually or automatically 23. The opening degree of the valve 32 may be adjusted by adjusting the ratio of the flow rate of water supplied to the side of the first space 14 and the flow rate of water supplied to the side of the second space 16 .

When the flow rate of permeate water and the flow rate of concentrated water are insufficient, it is only necessary to increase the frequency of the inverter 20 of the pump 18 to increase the supply of distilled water.

A valve 23 with an adjustable opening and closing degree can be installed at the outlet of the first space 14 of the piping 28, and the flow rate of concentrated water, the pressure of the inlet of the first space 14 and the outlet of the first space 14 can be adjusted by the opening of the valve 23 .

Through these operations, the pressure and various flow rates on the predetermined side of the first space 14 can be adjusted.

Also, a concentrated water tank for storing concentrated water may be provided in the middle of the piping 34, and the distilled water may be supplied to the first space 14 side and the concentrated water to the second space 16 side by separate pumps. In the case where the distilled water and the concentrated water are supplied by separate pumps, an inverter for controlling the driving frequency may be provided in each pump.

By flowing distilled water to the first space 14 side and concentrated water with a similar concentration to the second space 16 side, the osmotic pressure generated by the semi-permeable membrane 12 can be reduced and the necessary pressure can be reduced. As a result, "distilled water at a concentration that cannot be concentrated by the conventional reverse osmosis membrane method" can be concentrated.

In the water treatment method and water treatment device according to this embodiment, before the liquid is sent to the distillation device 11 (in the case of pretreatment means, after the pretreatment and before the liquid is sent to the distillation device 11), the ammonia-containing For example, the concentration of sulfuric acid ion is above 6000mg/L, and the concentration of ammonium ion is above 2000mg/L. The sulfate ion concentration of the ammonia-containing water is preferably 20,000 mg/L, more preferably 20,000-250,000 mg/L. The ammonium ion concentration of the ammonia-containing water is preferably above 2000 mg/L, more preferably in the range of 2000-100000 mg/L.

The inlet pressure of the first space 14 is preferably set at the range below 7MPa, the inlet pressure of the second space 16 is preferably set at a pressure less than the inlet pressure of the first space 14, and the inlet pressure of the second space 16 is more preferably Make it 50% or less of the inlet pressure of the 1st space 14. Thereby, the risk of damage to the semi-permeable membrane caused by pressure can be reduced.

Also, it is preferable to make the flow rate on the side of the first space 14 larger than the flow rate on the side of the second space 16 . If the flow rate on the side of the first space 14 is lower than the flow rate on the side of the second space 16 , the permeate flow rate may be too high. For example, the pump 18, the inverter 20, the valve 22, the valve 23, the valve 32, etc., function as a flow rate adjustment means that makes the flow rate in the first space larger than the flow rate in the second space.

If the permeate flow rate is too large, there may be problems that the concentration difference becomes large, the risk of fouling becomes high, and the pressure becomes too high. Also, if the permeate flux is too small, the concentration efficiency may deteriorate. From these contents, it is preferable to set the permeation flux of the membrane module 10 in the range of 0.005 m/d to 0.05 m/d, more preferably in the range of 0.015 m/d to 0.04 m/d. Also, the permeate flux is defined as the permeate flux per unit time and unit membrane area. For example, the pump 18, the inverter 20, the valve 22, the valve 23, the valve 32, etc., function as permeate flux adjustment means for controlling the permeate flux within the above range.

In addition, the installation positions and the number of valves are merely examples, and the valves may be larger than those shown in FIGS. 1 and 2 , and may be installed in at least one of the other piping. In addition, at least one of each piping may be provided with a flow meter as a flow measurement means for measuring a flow rate, and a pressure gauge as a pressure measurement means for measuring a pressure.

In the water treatment method and water treatment device according to this embodiment, a multi-stage semi-permeable membrane module can also be used. An example of a water treatment device configured in this way is shown in FIG. 3 , FIG. 4 , and FIG. 5 . The water treatment device shown in Fig. 3, Fig. 4 and Fig. 5 has a structure in which three sections of semi-permeable membrane modules are combined in series.

The water treatment device 3 shown in Fig. 3 comprises: as the distillation unit 11 of the first recovery means, at least one of ammonia and ammonium ions is recovered as the first recovery product from the ammonia-containing water; and as the second recovery means For example, the first section membrane module 10a, the second section membrane module 10b, and the third section membrane module 10c, by using the first space (concentrating side) 14 and the second space ( The semi-permeable membrane module connected to multiple sections of the permeation side) 16, and the first space 14 of the first semi-permeable membrane module flows through the distilled water of the distillation device 11, and the first space 14 is pressurized to make the distilled water The contained water permeates the semi-permeable membrane 12 to obtain concentrated water, and then uses the semi-permeable membrane module after the next stage to further use this concentrated water as concentrated water to obtain the second reclaimed product. A part of distilled water or a part of concentrated water flows through the second space 16 of the module to obtain dilution water. Each membrane module has a first space 14 and a second space 16 separated by a semipermeable membrane 12 . The water treatment device 3 may also be equipped with a dilution tank 60a for storing the dilution water from the first membrane module 10a, a dilution tank 60b for storing the dilution water from the second membrane module 10b, and a dilution tank 60b for storing the dilution water from the third membrane module 10b. The dilution water tank 60c where the dilution water of the section film module 10c is stored. The membrane module 10 is to supply the distilled water to the first space and the second space of the first membrane module, and supply the concentrated water to the first space and the second space of the next membrane module in sequence for concentration processing device. The water treatment device 3 may include a distilled water tank for storing distilled water between the distiller 11 and the membrane module 10 .

In the water treatment device 3 shown in FIG. 3 , a pipe 25 is connected to the inlet of the distillation device 11 . A pipe 27 is connected to the first recovered product outlet of the distillation apparatus 11 . The distilled water outlet of the distillation device 11 and the first space inlet of the first-stage membrane module 10 a are connected through a pump 18 and a pipe 40 . A pipe 42 branched from the pipe 40 on the downstream side of the pump 18 is connected to the second space inlet of the membrane module 10a via the valve 22a. The outlet of the second space of the first-stage membrane module 10 a and the inlet of the dilution water tank 60 a are connected by a pipe 46 . The outlet of the first space of the first-stage membrane module 10 a and the inlet of the first space of the second-stage membrane module 10 b are connected by a pipe 44 . A pipe 48 branched from the pipe 44 is connected to the second space inlet of the second-stage membrane module 10b via the valve 22b. The outlet of the second space of the second-stage membrane module 10b and the inlet of the dilution tank 60b are connected by a pipe 52 . The outlet of the first space of the second-stage membrane module 10b and the inlet of the first space of the third-stage membrane module 10c are connected by a pipe 50 . A pipe 54 branched from the pipe 50 is connected to the second space inlet of the third-stage membrane module 10c via the valve 22c. The outlet of the second space of the third-stage membrane module 10c and the inlet of the dilution tank 60c are connected by a pipe 58 . A pipe 56 is connected to the outlet of the first space of the third-stage membrane module 10c via the valve 23 .

The membrane module 10 uses a multi-stage membrane module with a first space 14 and a second space 16 separated by a semi-permeable membrane 12, and provides distillation treatment to the first space and the second space of the first-stage membrane module water, and then supply the concentrated water to the first space and the second space of the next membrane module in sequence, and pressurize the first space 14 of each section to make the water contained in the first space 14 pass through half The permeable membrane 12 penetrates into the second space 16 to concentrate the water. That is, in the membrane module 10 , the distilled water is concentrated using the semipermeable membrane 12 , and the concentrated water is further concentrated using the semipermeable membrane 12 of the next stage.

In the water treatment device 3 , ammonia-containing water containing ammonia is supplied to the distillation device 11 through a pipe 25 . Distillation is performed in the distillation device 11 to recover at least one of ammonia and ammonium ions from the ammonia-containing water as a first recovery product (first recovery step). The first recyclate is discharged through the pipe 27 .

The distilled water obtained in the distillation device 11 will be sent to the first space 14a of the first-stage membrane module 10a by the pump 18 through the pipe 40 when the valve 23 is open, and the distilled water branched from the pipe 40 The treated water is sent to the second space 16a of the first-stage membrane module 10a through the piping 42 when the valve 22a is opened. In the first stage membrane module 10a, pressurize the first space 14a so that the water contained in the first space 14a permeates into the second space 16a through the semipermeable membrane 12a (concentration step (first stage)), and at the same time Dilution water is obtained in the second space 16a (dilution step (first stage)). The dilution water obtained in the second space 16a of the first-stage membrane module 10a is stored in the dilution water tank 60a through the piping 46 as needed, and then discharged to the outside of the system.

The concentrated water obtained in the first space 14a of the first stage membrane module 10a is sent to the first space 14b of the second stage membrane module 10b through the pipe 44, and the concentrated water branched from the pipe 44 is passed through the valve. When 22b is in an open state, the liquid is sent to the second space 16b of the second-stage membrane module 10b through the pipe 48 . In the second-stage membrane module 10b, the first space 14b is pressurized so that the water contained in the first space 14b permeates into the second space 16b through the semi-permeable membrane 12b (concentration step (second stage)), and at the same time Dilution water is obtained in the second space 16b (dilution step (second stage)). The dilution water obtained in the second space 16b of the second-stage membrane module 10b is stored in the dilution water tank 60b through the piping 52 as needed, and then discharged to the outside of the system.

The concentrated water obtained in the first space 14b of the second stage membrane module 10b is sent to the first space 14c of the third stage membrane module 10c through the pipe 50, and the concentrated water branched from the pipe 50 is passed through the valve. When 22c is in an open state, the liquid is sent to the second space 16c of the third-stage membrane module 10c through the pipe 54 . In the third stage membrane module 10c, the first space 14c is pressurized so that the water contained in the first space 14c permeates into the second space 16c through the semipermeable membrane 12c (concentration step (third stage)), and at the same time Dilution water is obtained in the second space 16c (dilution step (third stage)) (above, second recovery step). The dilution water obtained in the second space 16c of the third-stage membrane module 10c is stored in the dilution water tank 60c through the piping 58 as needed, and then discharged to the outside of the system. The concentrated water obtained in the first space 14c of the third-stage membrane module 10c is discharged through the pipe 56 as the second recovered product.

Here, the pump 18, the piping 40, 42, 44, 48, 50, 54, etc., serve as the first spaces 14a, 14b, 14c and the second spaces 16a, 16b, 16c functions as a means for supplying distilled water or concentrated water.

The dilution water obtained in the second space 16a, 16b, 16c of each membrane module 10a, 10b, 10c can be discharged out of the system, or sent to the dilution water tank 60a, 60b, 60c for storage as required, It can also be reused after being discharged out of the system. At least a part of the dilution water may be sent to the distillation treatment water tank, and may be mixed with the distillation treatment water in the distillation treatment water tank. About at least a part of dilution water, you may further perform other processing, for example, perform reverse osmosis membrane processing as mentioned later.

As described above, at least one of ammonia and ammonium ions is recovered as the first recovered product from the ammonia-containing water that is the object of treatment, and the concentrated water after the ions are concentrated (the concentrated water in the final stage) It is recovered as the second recovered product to obtain dilution water (dilution water of each stage) to reduce the volume of ammonia-containing water. In addition, the first recovered material, the second recovered material, and the dilution water can be reused.

The water treatment device 4 shown in Figure 4 comprises: a distillation device 11 as a first recovery means, from ammonia-containing water, at least one of ammonia and ammonium ions is recovered as a first recovery; and as a second recovery means For example, the first section membrane module 10a, the second section membrane module 10b, and the third section membrane module 10c, by using the first space (concentrating side) 14 and the second space ( The semi-permeable membrane module connected to multiple sections of the permeation side) 16, and the first space 14 of the first semi-permeable membrane module flows through the distilled water of the distillation device 11, and the first space 14 is pressurized to make the distilled water The contained water permeates the semi-permeable membrane 12 to obtain concentrated water, and then uses the semi-permeable membrane module after the next stage to further use this concentrated water as concentrated water to obtain the second reclaimed product. The second space 16 of the module passes through at least a part of the concentrated water to obtain dilution water. Each membrane module has a first space 14 and a second space 16 separated by a semipermeable membrane 12 . The water treatment device 4 may also include: a dilution tank 62a that stores the dilution water from the first membrane module 10a, a dilution tank 62b that stores the dilution water from the second membrane module 10b, and a dilution tank 62b that stores the dilution water from the second membrane module 10b. The dilution water tank 62c where the dilution water of the three-stage membrane module 10c is stored. The membrane module 10 is to supply distilled water to the first space of the first membrane module, and supply the concentrated water to the first space of the next membrane module and its own second space in order for concentration treatment installation. The water treatment device 4 may include a distilled water tank for storing distilled water between the distiller 11 and the membrane module 10 .

In the water treatment device 4 shown in FIG. 4 , a pipe 25 is connected to the inlet of the distillation device 11 . A pipe 27 is connected to the first recovered product outlet of the distillation apparatus 11 . The distilled water outlet of the distillation device 11 and the first space inlet of the first-stage membrane module 10 a are connected through a pump 18 and a pipe 40 . The outlet of the first space of the first-stage membrane module 10 a and the inlet of the first space of the second-stage membrane module 10 b are connected by a pipe 44 . A pipe 64 branched from the pipe 44 is connected to the second space inlet of the membrane module 10a via the valve 32a. The outlet of the second space of the first-stage membrane module 10 a and the inlet of the dilution water tank 62 a are connected by a pipe 66 . The outlet of the first space of the second-stage membrane module 10b and the inlet of the first space of the third-stage membrane module 10c are connected by a pipe 50 . The pipe 68 branched from the pipe 50 is connected to the second space inlet of the membrane module 10b via the valve 32b. The outlet of the second space of the second-stage membrane module 10b and the inlet of the dilution tank 62b are connected by a pipe 70 . A pipe 56 is connected to the outlet of the first space of the third-stage membrane module 10c via the valve 23 . The pipe 72 branched from the pipe 56 on the upstream side of the valve 23 enters into the second space of the membrane module 10c via the valve 32c. The outlet of the second space of the third-stage membrane module 10c and the inlet of the dilution water tank 62c are connected by a pipe 74 .

The membrane module 10 is by using a multi-stage membrane module having a first space 14 and a second space 16 separated by a semi-permeable membrane 12, and supplying distilled water to the first space of the first stage membrane module, Then the concentrated water is supplied to the first space of the next membrane module and its own second space in sequence, and the first space 14 of each section is pressurized so that the water contained in the first space 14 passes through the semi-permeable membrane 12 A device that penetrates into the second space 16 to concentrate the water. That is, in the membrane module 10 , the distilled water is concentrated by using the semipermeable membrane 12 , and then the concentrated water is further concentrated by using the semipermeable membrane 12 of the next stage.

In the water treatment device 4 , the ammonia-containing water system containing ammonia is supplied to the distillation device 11 through the pipe 25 . Distillation is performed in the distillation device 11 to recover at least one of ammonia and ammonium ions from the ammonia-containing water as a first recovery product (first recovery step). The first recyclate is discharged through the pipe 27 .

The distilled water obtained in the distillation device 11 is sent to the first space 14a of the first-stage membrane module 10a by the pump 18 through the piping 40 when the valve 23 is opened. In the first stage membrane module 10a, the first space 14a is pressurized so that the water contained in the first space 14a permeates into the second space 16a through the semipermeable membrane 12a (concentration step (first stage)), and at the same time Dilution water is obtained in the second space 16a (dilution step (first stage)). The concentrated water obtained in the first space 14a of the first stage membrane module 10a is sent to the first space 14b of the second stage membrane module 10b through the pipe 44, and the concentrated water branched from the pipe 44 is passed through the valve. When 32a is in the open state, the liquid is sent to the second space 16a of the first-stage membrane module 10a through the pipe 64 . The dilution water obtained in the second space 16a of the first-stage membrane module 10a is stored in the dilution water tank 62a through the piping 66 as needed, and then discharged to the outside of the system.

In the second-stage membrane module 10b, the first space 14b is pressurized so that the water contained in the first space 14b permeates into the second space 16b through the semi-permeable membrane 12b (concentration step (second stage)), and at the same time Dilution water is obtained in the second space 16b (dilution step (second stage)). The concentrated water obtained in the first space 14b of the second stage membrane module 10b is sent to the first space 14c of the third stage membrane module 10c through the pipe 50, and the concentrated water branched from the pipe 50 is passed through the valve. When 32b is in an open state, the liquid is sent to the second space 16b of the second-stage membrane module 10b through the pipe 68 . The dilution water obtained in the second space 16b of the second-stage membrane module 10b is stored in the dilution water tank 62b through the piping 70 as needed, and then discharged to the outside of the system.

In the third stage membrane module 10c, the water contained in the first space 14c is permeated into the second space 16c through the semipermeable membrane 12c by pressurizing the first space 14c (concentration step (third stage)) , while obtaining dilution water in the second space 16c (dilution step (third stage)) (above, second recovery step). The concentrated water obtained in the first space 14c of the third-stage membrane module 10c is discharged through the pipe 56 as the second recovered product. The concentrated water branched from the pipe 56 is sent to the second space 16c of the third-stage membrane module 10c through the pipe 72 when the valve 32c is opened. The dilution water obtained in the second space 16c of the third-stage membrane module 10c is stored in the dilution water tank 62c through the piping 74 as needed, and then discharged to the outside of the system.

Here, the pump 18, the piping 40, 44, 64, 50, 68, 56, 72, etc., serve as the first spaces 14a, 14b, 14c and the second spaces 16a, 16a, 16b and 16c function as supply means for distilled water or concentrated water.

The dilution water obtained in the second space 16a, 16b, 16c of each membrane module 10a, 10b, 10c can be discharged out of the system, or can be sent to the dilution water tank 62a, 62b, 62c for storage as required, It can also be reused after being discharged out of the system. At least a part of the dilution water may be sent to the distillation treatment water tank, and may be mixed with the distillation treatment water in the distillation treatment water tank. About at least a part of dilution water, you may further perform other processing, for example, perform reverse osmosis membrane processing as mentioned later.

As described above, at least one of ammonia and ammonium ions is recovered as the first recovered product from the ammonia-containing water that is the object of treatment, and the concentrated water after the ions are concentrated (the concentrated water in the final stage) It is recovered as the second recovered product to obtain dilution water (dilution water of each stage) to reduce the volume of ammonia-containing water. In addition, the first recovered material, the second recovered material, and the dilution water can be reused.

When multi-stage membrane modules are used, the water flow on the second space side can also be performed in series. An example of a water treatment device configured in this way is shown in FIG. 5 .

The water treatment device 5 shown in Fig. 5 comprises: a distillation device 11 as a first recovery means, from ammonia-containing water, at least one of ammonia and ammonium ions is recovered as a first recovery; and as a second recovery means For example, the first section membrane module 10a, the second section membrane module 10b, and the third section membrane module 10c, by using the first space (concentrating side) 14 and the second space ( The semi-permeable membrane module connected to multiple sections of the permeation side) 16, and the first space 14 of the first semi-permeable membrane module flows through the distilled water of the distillation device 11, and the first space 14 is pressurized to make the distilled water The contained water permeates the semi-permeable membrane 12 to obtain concentrated water, and then uses the semi-permeable membrane module after the next stage to further use this concentrated water as concentrated water to obtain the second reclaimed product. The second space 16 of the module circulates at least a part of the concentrated water or at least a part of the diluted water obtained from other semi-permeable membrane modules to obtain the diluted water. Each membrane module has a first space 14 and a second space 16 separated by a semipermeable membrane 12 . The membrane module 10 is a device for supplying distilled water to the first space of the first membrane module, and sequentially supplying the concentrated water to the first space of the next membrane module for concentration treatment. The water treatment device 5 may include a distilled water tank for storing distilled water between the distiller 11 and the membrane module 10 .

In the water treatment device 5 shown in FIG. 5 , a pipe 25 is connected to the inlet of the distillation device 11 . A pipe 27 is connected to the first recovered product outlet of the distillation apparatus 11 . The distilled water outlet of the distillation device 11 and the first space inlet of the first-stage membrane module 10 a are connected through a pump 18 and a pipe 40 . The outlet of the first space of the first-stage membrane module 10 a and the inlet of the first space of the second-stage membrane module 10 b are connected by a pipe 44 . The outlet of the first space of the second-stage membrane module 10b and the inlet of the first space of the third-stage membrane module 10c are connected by a pipe 50 . A pipe 56 is connected to the outlet of the first space of the third-stage membrane module 10c via the valve 23 . The piping 76 branched from the piping 56 on the upstream side of the valve 23 is connected to the second space inlet of the third-stage membrane module 10 c via the valve 32 . The outlet of the second space of the third-stage membrane module 10c and the inlet of the second space of the second-stage membrane module 10b are connected by a pipe 78 . The outlet of the second space of the second-stage membrane module 10b and the inlet of the second space of the first-stage membrane module 10a are connected by a pipe 80 . A pipe 82 is connected to the outlet of the second space of the first-stage membrane module 10a.

The membrane module 10 is by using a multi-stage membrane module having a first space 14 and a second space 16 separated by a semi-permeable membrane 12, and supplying distilled water to the first space of the first stage membrane module, Then, the concentrated water is circulated to the first space of the next membrane module in series, and then at least a part of the concentrated water of the last membrane module is supplied to the second space of itself, and then connected in series. The obtained dilution water circulates through the second space of the membrane module in the front section, and the first space 14 of each section is pressurized so that the water contained in the first space 14 permeates into the second space 16 through the semi-permeable membrane 12, so that Water concentration device. That is, in the membrane module 10 , the distilled water is concentrated using the semipermeable membrane 12 , and the concentrated water is further concentrated using the semipermeable membrane 12 of the next stage.

In the water treatment device 5 , ammonia-containing water is supplied to the distillation device 11 through a pipe 25 . Distillation is performed in the distillation device 11 to recover at least one of ammonia and ammonium ions from the ammonia-containing water as a first recovery product (first recovery step). The first recyclate is discharged through the pipe 27 .

The distilled water obtained in the distillation device 11 is sent to the first space 14a of the first-stage membrane module 10a by the pump 18 through the piping 40 when the valve 23 is opened. On the other hand, the dilution water sent through the second space 16c of the third-stage membrane module 10c and the second space 16b of the second-stage membrane module 10b described later is sent to the first-stage membrane through the pipe 80. The second space 16a of the module 10a. In the first stage membrane module 10a, the first space 14a is pressurized so that the water contained in the first space 14a permeates into the second space 16a through the semipermeable membrane 12a (concentration step (first stage)), and at the same time Dilution water is obtained in the second space 16a (dilution step (first stage)). The concentrated water obtained in the first space 14a of the first-stage membrane module 10a is sent to the first space 14b of the second-stage membrane module 10b through the pipe 44 . The dilution water obtained in the second space 16a of the first-stage membrane module 10a is discharged out of the system through the pipe 82 .

In the second-stage membrane module 10b, the dilution water sent through the second space 16c of the third-stage membrane module 10c described later is sent to the second space 16b of the second-stage membrane module 10b through the pipe 78 . Also, by pressurizing the first space 14b, the water contained in the first space 14b permeates into the second space 16b through the semipermeable membrane 12b (concentration step (second stage)), and at the same time obtains dilution in the second space 16b. Water (dilution step (second paragraph)). The concentrated water obtained in the first space 14b of the second-stage membrane module 10b is sent to the first space 14c of the third-stage membrane module 10c through the pipe 50 . The dilution water obtained in the second space 16b of the second-stage membrane module 10b is sent to the second space 16a of the first-stage membrane module 10a through the pipe 80 .

In the third-stage membrane module 10c, as described below, the concentrated water obtained in the first space 14c of the third-stage membrane module 10c is sent to the second space 16c through the pipes 56 and 76 . Also, by pressurizing the first space 14c, the water contained in the first space 14c permeates into the second space 16c through the semipermeable membrane 12c (concentration step (third stage)), and at the same time obtains dilution in the second space 16c. Water (dilution step (third stage)) (above, second recovery step). The concentrated water obtained in the first space 14c of the third-stage membrane module 10c is discharged through the pipe 56 as the second recovered product. The concentrated water branched from the pipe 56 is sent to the second space 16c of the third-stage membrane module 10c through the pipe 76 when the valve 32 is opened. The dilution water obtained in the second space 16c of the third-stage membrane module 10c is sent to the second space 16b of the second-stage membrane module 10b through the pipe 78 .

Here, the pump 18, the piping 40, 44, 50, 56, 76, 78, 80, etc. are used as the first space 14a, 14b, 14c and the second space 16a, 16b and 16c function by supplying means for supplying distilled water, concentrated water, or diluted water.

The dilution water obtained in the second space 16a of the membrane module 10a can be discharged to the outside of the system, or can be sent to the dilution water tank for storage as required, and then discharged to the outside of the system or reused. At least a part of the dilution water may be sent to the distillation treatment water tank, and may be mixed with the distillation treatment water in the distillation treatment water tank. About at least a part of dilution water, you may further perform another process, for example, perform reverse osmosis membrane process as mentioned later.

As described above, at least one of ammonia and ammonium ions is recovered as the first recovered product from the ammonia-containing water that is the object of treatment, and the concentrated water after the ions are concentrated (the concentrated water in the final stage) It is recovered as the second recovered product to obtain dilution water (dilution water of the first stage) for volume reduction of ammonia-containing water. In addition, the first recovered material, the second recovered material, and the dilution water can be reused.

In the water treatment device 3 shown in FIG. 3, the water treatment device 4 shown in FIG. 4, and the water treatment device 5 shown in FIG. The concentrated water of the module will continue to be concentrated, so it will become a high concentration. Since it will be concentrated to a high concentration in the end, by this method that can reduce the osmotic pressure, it can be concentrated to "a concentration that was difficult to concentrate due to the influence of osmotic pressure in the conventional reverse osmosis membrane method."

When the distilled water is supplied to the first-stage membrane module 10a, for example, a pressure of 7 MPa or less is applied, and the supply of concentrated water to the latter-stage membrane module can be performed by applying the pressure to the first-stage membrane module 10a. . The inlet pressure of the first space 14 in each membrane module is preferably set at the range below 7MPa, the inlet pressure of the second space 16 is preferably set at a pressure less than the inlet pressure of the first space 14, and the second The inlet pressure of the space 16 is more preferably 50% or less of the inlet pressure of the first space 14 . Thereby, the risk of damage to the semi-permeable membrane caused by pressure can be reduced.

Also, it is preferable to make the flow rate on the side of the first space 14 larger than the flow rate on the side of the second space 16 in each membrane module 10 . If the flow rate on the side of the first space 14 is lower than the flow rate on the side of the second space 16, the flow rate on the side of the first space 14 of the subsequent membrane module may be insufficient. For example, the pump 18, the inverter 20, the valves 22a, 22b, 22c, the valve 23, the valves 32a, 32b, 32c, the valve 32, etc., are used as flow adjustment means to make the flow rate of the first space greater than the flow rate of the second space. function.

If the permeate flow rate is too large, there may be problems such as increased concentration polarization on the membrane surface, increased risk of fouling, and increased pressure. Also, if the permeate flux is too small, the concentration efficiency may deteriorate. From these contents, it is preferable to set the permeation flux of each membrane module 10 in the range of 0.005m/d to 0.05m/d, more preferably in the range of 0.015m/d to 0.04m/d . For example, the pump 18, the inverter 20, the valves 22a, 22b, 22c, the valve 23, the valves 32a, 32b, 32c, the valve 32, etc., function as permeate flux adjustment means to control the permeate flux within the above range. .

Moreover, the installation position and installation number of valves are only an example, and may be more than the number shown in FIG. 3, FIG. 4, and FIG. 5, and may be installed in at least one of other piping. In addition, a flow meter as a flow measurement means for measuring a flow rate and a pressure gauge as a pressure measurement means for measuring a pressure may be provided in at least one of each piping.

3, 4, and 5 are examples of the device configuration, and the arrangement of the semipermeable membrane modules and the method of supplying the supply water can be appropriately changed.

The water treatment device of Fig. 5, because each first space and the second space of each stage membrane module are circulated in series, so compared with the water treatment device of Fig. 3, Fig. 4, owing to can restrain the overall water quantity, And it can reduce the power of the pump, so it is better.

In the water treatment method and water treatment device according to this embodiment, a multi-stage membrane module can also be used, and a membrane module unit with "a plurality of membrane modules connected in parallel" can be used as the membrane module of each stage . An example of a water treatment device configured in this way is shown in FIGS. 6 and 7 . The water treatment device shown in Figure 6 and Figure 7 has a structure of four sections connected in series. The first section is a combination of semi-permeable membrane modules in a parallel four-row manner, and the second section is a parallel four-row combination of semi-permeable membrane modules. For the permeable membrane module, the semipermeable membrane module is combined in parallel in two rows in the third section, and the semipermeable membrane module is combined in parallel in two rows in the fourth section.

The water treatment device 6 shown in Figure 6 comprises: a distillation device 11 as a first recovery means, from ammonia-containing water, at least one of ammonia and ammonium ions is recovered as a first recovery product; and as a second recovery means For example, the first section of membrane module unit 100a, the second section of membrane module unit 100b, the third section of membrane module unit 100c, and the fourth section of membrane module unit 100d, by using the first section of membrane module unit 100a separated by the semipermeable membrane 12 The first space (concentration side) 14 and the second space (permeation side) 16 are semi-permeable membrane modules connected by multiple sections, and the first space 14 of the first semi-permeable membrane module flows through the distillation device 11 for distilled water , and pressurize the first space 14 so that the water contained in the distilled water permeates the semipermeable membrane 12 to obtain concentrated water, and then use the semipermeable membrane module after the next stage to further use this concentrated water as concentrated water to obtain For the second recovery, a part of the distilled water or a part of the concentrated water flows through the second space 16 of each semi-permeable membrane module at the same time, so as to obtain dilution water. The first section of membrane module unit 100a, for example, has four membrane modules connected in parallel, the second section of membrane module unit 100b, for example, has four membrane modules connected in parallel, and the third section of membrane module unit 100c, for example, has four membrane modules connected in parallel. For example, the fourth membrane module unit 100d includes two membrane modules connected in parallel. Each membrane module 10 has a first space 14 and a second space 16 separated by a semipermeable membrane 12 . The water treatment device 6 may also include a distilled water tank 84 for storing distilled water, and a concentrated water tank 86 for storing concentrated water from the fourth-stage membrane module unit 100d. The membrane module unit 100 is to supply the distilled water to the first space and the second space of each membrane module of the first membrane module unit, and supply the concentrated water to each membrane of the next membrane module unit in sequence The first space and the second space of the module are devices for concentration treatment.

In the water treatment device 6 shown in FIG. 6 , a pipe 25 is connected to the inlet of the distillation device 11 . A pipe 27 is connected to the first recovered product outlet of the distillation apparatus 11 . The outlet of the distilled water of the distillation apparatus 11 and the inlet of the distilled water tank 84 are connected by a pipe 29 . The outlet of the distillation treatment water tank 84 is connected to the inlet of the first space and the inlet of the second space of each membrane module of the first-stage membrane module unit 100 a through the pump 18 and through the pipe 88 . The first space outlet of each membrane module of the first stage membrane module unit 100 a and the first space inlet and the second space inlet of each membrane module of the second stage membrane module unit 100 b are connected by a pipe 90 . The outlet of the first space of each membrane module of the second-stage membrane module unit 100b and the inlet of the first space and the inlet of the second space of each membrane module of the third-stage membrane module unit 100c are connected by a pipe 94 . The first space outlet of each membrane module of the third stage membrane module unit 100c and the first space inlet and the second space inlet of each membrane module of the fourth stage membrane module unit 100d are connected by a pipe 98 . The outlet of the first space of each membrane module of the fourth-stage membrane module unit 100d is connected to the inlet of the concentrated water tank 86 by a pipe 104 . The second space outlet of each membrane module of the first stage membrane module unit 100a is connected with piping 92, and the second space outlet of each membrane module of the second stage membrane module unit 100b is connected with piping 96. The second space outlet of each membrane module of the three-stage membrane module unit 100c is connected with piping 102, and the second space outlet of each membrane module of the fourth section membrane module unit 100d is connected with piping 106, and piping 96, 102 , 106 can also join the pipe 92.

The membrane module unit 100 is a multi-stage membrane module unit equipped with a "membrane module 10 having a first space 14 and a second space 16 separated by a semi-permeable membrane 12", and the first section of the membrane module The first space and the second space of each membrane module of the unit are supplied with distilled water, and then the concentrated water is sequentially supplied to the first space and the second space of each membrane module of the next membrane module unit, and by A device for concentrating water by pressurizing the first space 14 of each section of the membrane module so that the water contained in the first space 14 permeates through the semi-permeable membrane 12 to the second space 16 . That is, in the membrane module unit 100 , the distilled water is concentrated by using the semipermeable membrane 12 , and then the concentrated water is further concentrated by using the semipermeable membrane 12 of the next stage.

In the water treatment device 6 , ammonia-containing water is supplied to the distillation device 11 through a pipe 25 . Distillation is performed in the distillation device 11 to recover at least one of ammonia and ammonium ions from the ammonia-containing water as a first recovery product (first recovery step). The first recyclate is discharged through the pipe 27 .

The distilled treatment water obtained in the distillation device 11 is stored in the distilled treatment water tank 84 as required, and is sent to each membrane module of the first stage membrane module unit 100a by the pump 18 from the distilled treatment water tank 84 through the piping 88 The first space 14 and the second space 16. In each membrane module of the first stage membrane module unit 100a, the first space 14 is pressurized so that the water contained in the first space 14 permeates into the second space 16 through the semi-permeable membrane 12 (concentrating step (first stage)), while obtaining dilution water in the second space 16 (dilution step (first stage)). The dilution water obtained in the second space 16 of the first-stage membrane module 10 is stored in the dilution water tank through the piping 92 as needed, and then discharged to the outside of the system.

The concentrated water obtained in the first space 14 of each membrane module of the first stage membrane module unit 100a is sent to the first space 14 of each membrane module of the second stage membrane module unit 100b through the piping 90 And the second space 16. In each membrane module of the second stage membrane module unit 100b, the first space 14 is pressurized so that the water contained in the first space 14 permeates into the second space 16 through the semi-permeable membrane 12 (concentrating step (second stage)), while obtaining dilution water in the second space 16 (dilution step (second stage)). The dilution water obtained in the second space 16 of each membrane module of the second-stage membrane module unit 100b is discharged to the outside of the system after being stored in the dilution water tank through the piping 96 as needed.

The concentrated water obtained in the first space 14 of each membrane module of the second stage membrane module unit 100b is sent to the first space 14 of each membrane module of the third stage membrane module unit 100c through the piping 94 And the second space 16. In each membrane module of the third stage membrane module unit 100c, the first space 14 is pressurized so that the water contained in the first space 14 permeates into the second space 16 through the semi-permeable membrane 12 (concentration step (third paragraph)), while obtaining dilution water in the second space 16 (dilution step (third paragraph)). The dilution water obtained in the second space 16 of each membrane module of the third-stage membrane module unit 100c is discharged to the outside of the system after being stored in the dilution water tank through the piping 102 as needed.

The concentrated water obtained in the first space 14 of each membrane module of the third stage membrane module unit 100c is sent to the first space 14 of each membrane module of the fourth stage membrane module unit 100d through the piping 98 And the second space 16. In each membrane module of the fourth stage membrane module unit 100d, the first space 14 is pressurized so that the water contained in the first space 14 permeates into the second space 16 through the semi-permeable membrane 12 (concentrating step (fourth) stage)), while obtaining dilution water in the second space 16 (dilution step (fourth stage)) (above, second recovery step). The concentrated water obtained in the first space 14 of each membrane module of the fourth-stage membrane module unit 100d is stored in the concentrated water tank 86 through the pipe 104 as needed, and then discharged as the second recovered product. The dilution water obtained in the second space 16 of each membrane module of the fourth-stage membrane module unit 100d is discharged to the outside of the system after being stored in the dilution water tank through the piping 106 as needed.

Here, the pump 18, the piping 88, 90, 94, 98, etc., are used as the first space 14 and the second space 16 of each membrane module unit 100a, 100b, 100c, 100d to provide distillation treatment. It functions as a means of supplying water or concentrated water.

The dilution water obtained in the second space 16 of each membrane module of each membrane module unit 100a, 100b, 100c, 100d can be discharged to the outside of the system, or can be sent to the dilution water tank for storage according to needs, and then discharged It can also be reused outside the system. At least a part of the dilution water may be sent to the distilled water tank 84 and mixed with the distilled water in the distilled water tank 84 . About at least a part of dilution water, you may further perform other processing, for example, perform reverse osmosis membrane processing as mentioned later.

As described above, at least one of ammonia and ammonium ions is recovered as the first recovered product from the ammonia-containing water that is the object of treatment, and the concentrated water after the ions are concentrated (the concentrated water in the final stage) It is recovered as the second recovered product, and dilution water (dilution water of each stage) is obtained to reduce the volume of ammonia-containing water. In addition, the first recovered material, the second recovered material, and the dilution water can be reused.

The water treatment device 7 shown in Fig. 7 comprises: as the distillation unit 11 of the first recovery means, at least one of ammonia and ammonium ions is recovered as the first recovery product from the ammonia-containing water; and as the second recovery means For example, the first section of membrane module unit 100a, the second section of membrane module unit 100b, the third section of membrane module unit 100c, and the fourth section of membrane module unit 100d, by using the first section of membrane module unit 100a separated by the semipermeable membrane 12 The first space (concentration side) 14 and the second space (permeation side) 16 are semi-permeable membrane modules connected by multiple sections, and the first space 14 of the first semi-permeable membrane module flows through the distillation device 11 for distilled water , and pressurize the first space 14 so that the water contained in the distilled water permeates the semi-permeable membrane 12 to obtain concentrated water, and then use the semi-permeable membrane module after the next stage to further use this concentrated water as concentrated water to obtain the second For the recyclate, at least a part of concentrated water or at least a part of dilution water obtained from other semi-permeable membrane modules flows through the second space 16 of each semi-permeable membrane module to obtain dilution water. The first section of membrane module unit 100a, for example, has four membrane modules connected in parallel, the second section of membrane module unit 100b, for example, has four membrane modules connected in parallel, and the third section of membrane module unit 100c, for example, has four membrane modules connected in parallel. For example, the fourth membrane module unit 100d includes two membrane modules connected in parallel. Each membrane module 10 has a first space 14 and a second space 16 separated by a semipermeable membrane 12 . The water treatment device 7 may also include a distilled water tank 84 for storing distilled water, and a concentrated water tank 86 for storing concentrated water from the fourth-stage membrane module unit 100d. The membrane module unit 100 is a device for supplying distilled water to the first space of the first membrane module, and sequentially supplying the concentrated water to the first space of the next membrane module for concentration treatment.

In the water treatment device 7 shown in FIG. 7 , a pipe 25 is connected to the inlet of the distillation device 11 . A pipe 27 is connected to the first recovered product outlet of the distillation apparatus 11 . The outlet of the distilled water of the distillation apparatus 11 and the inlet of the distilled water tank 84 are connected by a pipe 29 . The outlet of the distillation treatment water tank 84 is connected to the first space inlet of each membrane module of the first-stage membrane module unit 100 a through a pump 18 and through a pipe 108 . The outlet of the first space of each membrane module of the first-stage membrane module unit 100 a and the inlet of the first space of each membrane module of the second-stage membrane module unit 100 b are connected by a pipe 110 . The outlet of the first space of each membrane module of the second-stage membrane module unit 100b and the inlet of the first space of each membrane module of the third-stage membrane module unit 100c are connected by a pipe 112 . The outlets of the first spaces of the membrane modules of the third membrane module unit 100c and the inlets of the first spaces of the membrane modules of the fourth membrane module unit 100d are connected by pipes 114 . The outlet of the first space of each membrane module of the fourth-stage membrane module unit 100d and the inlet of the concentrated water tank 86 are connected by a pipe 116 . The piping 118 branched from the piping 116 is connected to the second space inlet of each membrane module of the fourth-stage membrane module unit 100d. The outlet of the second space of each membrane module of the fourth-stage membrane module unit 100d and the inlet of the second space of each membrane module of the third-stage membrane module unit 100c are connected by a pipe 120 . The outlets of the second spaces of the membrane modules of the third-stage membrane module unit 100c and the inlets of the second spaces of the membrane modules of the second-stage membrane module unit 100b are connected by pipes 122 . The outlet of the second space of each membrane module of the second-stage membrane module unit 100b is connected to the inlet of the second space of each membrane module of the first-stage membrane module unit 100a by a pipe 124 . A pipe 126 is connected to the outlet of the second space of each membrane module of the first-stage membrane module unit 100a.

The membrane module unit 100 is a multi-stage membrane module unit equipped with a "membrane module 10 having a first space 14 and a second space 16 separated by a semi-permeable membrane 12", and the first section of the membrane module The first space of each membrane module of the unit is supplied with distilled water, and then the concentrated water is circulated to the first space of each membrane module of the next membrane module unit in series, and the final membrane module At least a part of the concentrated water of each membrane module of the unit is supplied to its own second space, and then the dilution water obtained in the second space 16 of each membrane module of its previous membrane module unit is circulated in series, and borrowed A device that pressurizes the first space 14 of each section so that the water contained in the first space 14 permeates through the semipermeable membrane 12 to the second space 16 to concentrate the water. That is, in the membrane module unit 100 , the distilled water is concentrated by using the semipermeable membrane 12 , and then the concentrated water is further concentrated by using the semipermeable membrane 12 of the next stage.

In the water treatment device 7 , ammonia-containing water containing ammonia is supplied to the distillation device 11 through a pipe 25 . Distillation is performed in the distillation device 11 to recover at least one of ammonia and ammonium ions from the ammonia-containing water as a first recovery product (first recovery step). The first recyclate is discharged through the pipe 27 .

The distilled treatment water obtained in the distillation device 11 is stored in the distilled treatment water tank 84 as required, and is sent from the distilled treated water tank 84 through the piping 108 by the pump 18 to each membrane module of the first-stage membrane module unit 100a. The first space14. On the other hand, through the second space 16 of each membrane module of the fourth membrane module unit 100d described later, the second space 16 of each membrane module of the third membrane module unit 100c, the second membrane module The dilution water fed to the second space 16 of each membrane module of the unit 100b is sent to the second space 16 of each membrane module of the first-stage membrane module unit 100a through the pipe 124 . In each membrane module of the first stage membrane module unit 100a, the first space 14 is pressurized so that the water contained in the first space 14 permeates into the second space 16 through the semi-permeable membrane 12 (concentrating step (first stage)), while obtaining dilution water in the second space 16 (dilution step (first stage)). The concentrated water obtained in the first space 14 of each membrane module of the first stage membrane module unit 100a is sent to the first space 14 of each membrane module of the second stage membrane module unit 100b through the piping 110 . The dilution water obtained in the second space 16 of each membrane module of the first-stage membrane module unit 100 a is discharged out of the system through the pipe 126 .

In each membrane module of the second stage membrane module unit 100b, through the second space 16 of each membrane module of the fourth stage membrane module unit 100d described later, each membrane module of the third stage membrane module unit 100c The dilution water sent to the second space 16 is sent to the second space 16 of each membrane module of the second stage membrane module unit 100b through the piping 122 . Also, pressurizing the first space 14 causes the water contained in the first space 14 to permeate into the second space 16 through the semipermeable membrane 12 (concentration step (second stage)), and obtain dilution water (dilution water) in the second space 16 at the same time. steps (second paragraph)). The concentrated water obtained in the first space 14 of each membrane module of the second-stage membrane module unit 100b is sent to the first space 14 of each membrane module of the third-stage membrane module unit 100c through the piping 112 . The dilution water obtained in the second space 16 of each membrane module of the second stage membrane module unit 100b is sent to the second space 16 of each membrane module of the first stage membrane module unit 100a through the piping 124 .

In each membrane module of the third stage membrane module unit 100c, the dilution water sent through the second space 16 of each membrane module of the fourth stage membrane module unit 100d described later is sent to the The second space 16 of each membrane module of the third membrane module unit 100c. Also, the first space 14 is pressurized so that the water contained in the first space 14 permeates into the second space 16 through the semipermeable membrane 12 (concentration step (third stage)), and the dilution water ( dilution step (third paragraph)). The concentrated water obtained in the first space 14 of each membrane module of the third membrane module unit 100c is sent to the first space 14 of each membrane module of the fourth membrane module unit 100d through the piping 114 . The dilution water obtained in the second space 16 of each membrane module of the third stage membrane module unit 100c is sent to the second space 16 of each membrane module of the second stage membrane module unit 100b through the piping 122 .

In each membrane module of the fourth stage membrane module unit 100d, as described below, the concentrated water obtained in the first space 14 of each membrane module unit 100d of the fourth stage is passed through the piping 116, 118 sends liquid to the second space 16 . Also, pressurizing the first space 14 causes the water contained in the first space 14 to permeate into the second space 16 through the semi-permeable membrane 12 (concentration step (fourth stage)), and obtain dilution water (dilution water) in the second space 16 at the same time. Step (fourth paragraph)) (above, second recovery step). The concentrated water obtained in the first space 14 of each membrane module of the fourth-stage membrane module unit 100d is stored in the concentrated water tank 86 through the pipe 116 as needed, and then discharged as the second recovered product. The concentrated water branched from the piping 116 is sent to the second space 16 of each membrane module of the fourth-stage membrane module unit 100d through the piping 118 . The dilution water obtained in the second space 16 of each membrane module of the fourth membrane module unit 100d is sent to the second space 16 of each membrane module of the third membrane module unit 100c through the piping 120 .

Here, the pump 18, piping 108, 110, 112, 114, 116, 118, 120, 122, 124, etc., are used as the first of each membrane module of each section membrane module unit 100a, 100b, 100c, 100d. The space 14 and the second space 16 function as means for supplying distilled water, concentrated water, or diluted water.

The dilution water obtained in the second space 16 of each membrane module of the membrane module unit 100a can be discharged out of the system, or can be sent to the dilution water tank for storage as required, and then discharged out of the system or reused. At least a part of the dilution water may be sent to the distilled water tank 84 and mixed with the distilled water in the distilled water tank 84 . About at least a part of dilution water, you may further perform other processing, for example, perform reverse osmosis membrane processing as mentioned later.

As described above, at least one of ammonia and ammonium ions is recovered as the first recovered product from the ammonia-containing water that is the object of treatment, and the concentrated water after the ions are concentrated (the concentrated water in the final stage) It is recovered as the second recovered product to obtain dilution water (dilution water of each stage) for volume reduction of ammonia-containing water. In addition, the first recovered material, the second recovered material, and the dilution water can be reused.

When the distilled water is supplied to each membrane module of the first-stage membrane module unit 100a, for example, a pressure of 7 MPa or less is applied, and the supply of concentrated water to the rear-stage membrane module unit can only be carried out by applying to the first-stage membrane module. The pressure of each membrane module of the group unit 100a can be adjusted. The inlet pressure of the first space 14 in each membrane module is preferably set at the scope below 7MPa, and the inlet pressure of the second space 16 is preferably set at the pressure less than the inlet pressure of the first space 14, and the second space The inlet pressure of 16 is more preferably 50% or less of the inlet pressure of the first space 14 . Thereby, the risk of damage to the semi-permeable membrane caused by pressure can be reduced.

Also, it is preferable to set the flow rate on the side of the first space 14 in each membrane module 10 to be greater than the flow rate on the side of the second space 16 . If the flow rate on the side of the first space 14 is lower than the flow rate on the side of the second space 16, the flow rate on the side of the first space 14 of the subsequent membrane module may be insufficient. For example, the pump 18 and the like function as flow rate adjustment means for making the flow rate in the first space larger than the flow rate in the second space.

If the permeate flow rate is too large, there may be problems that the concentration difference becomes large, the risk of fouling becomes high, and the pressure becomes too high. Also, if the permeate flux is too small, the concentration efficiency may deteriorate. From the above, it is preferable to set the permeation flux of each membrane module 10 in the range of 0.005 m/d to 0.05 m/d, more preferably in the range of 0.015 m/d to 0.04 m/d. For example, the pump 18 and the like function as a permeate flux adjustment means for controlling the permeate flux to the above-mentioned range.

Moreover, a valve may be provided in at least one of each piping, and the installation position and number of valves are not particularly limited. In addition, at least one of the pipes may be provided with a flow meter as a flow measurement means for measuring a flow rate and a pressure gauge as a pressure measurement means for measuring a pressure.

6 and 7 are examples of device configurations, and the number of stages, parallel connections, arrangement, and supply method of the supply water of the semipermeable membrane modules can also be appropriately changed.

In order to concentrate the substances to be recovered in the distilled treated water as the second recovered product in the membrane module to a preferred concentration, it is preferable to combine multiple stages of the membrane module in series. When a multi-stage membrane module is used as in the water treatment devices 3, 4, 5, 6, 7, the number of stages of the membrane module may depend on the concentration of the target treated water and the like. For example, when it is desired to obtain treated water having a higher concentration from distilled treated water having a lower concentration, the number of stages of the membrane module unit can be increased.

When using a plurality of membrane modules connected in parallel as the membrane module units of each section of membrane modules like water treatment devices 6 and 7, the number of membrane modules in each membrane module unit can depend on the distillation Handle water flow, etc.

Concentration water tanks and dilution water tanks may also be provided in more than one section of membrane modules, and concentration water tanks and dilution water tanks may also be provided in each section of membrane modules.

Water to be treated, that is, ammonia-containing water, is not particularly limited as long as it is water containing ammonium ions. Ammonia-containing water is, for example, water containing sulfate ions and ammonium ions, and examples thereof include wastewater discharged from semiconductor factories, wastewater discharged from chemical factories, and the like. In particular, in semiconductor factories, ammonia is used for cleaning of wafers and the like, and sulfuric acid is used for cleaning treatment of ammonia. Therefore, ammonium ions and sulfate ions are contained in the wastewater. As an effective utilization of wastewater, ammonia and sulfuric acid in wastewater are recovered and reused.

The distiller 11 is not particularly limited as long as it can recover ammonia from ammonia-containing water including ammonia by distillation. As the distillation apparatus 11, a membrane distillation apparatus which recovers volatile ammonia via a gas permeable membrane, a vacuum distillation apparatus, etc. are mentioned, for example. For example, ammonia recovered as gas in the distillation apparatus 11 may be added to sulfuric acid and recovered as ammonium sulfate. Thereby, high-purity ammonium sulfate can be recovered.

As the semipermeable membrane 12 included in the membrane module, semipermeable membranes such as a reverse osmosis membrane (RO membrane), a forward osmosis membrane (FO membrane), and a nanofiltration membrane (NF membrane) may be exemplified. The semipermeable membrane is preferably a reverse osmosis membrane, a forward osmosis membrane, or a nanofiltration membrane.

The material constituting the semipermeable membrane 12 is not particularly limited, and examples thereof include cellulose resins such as cellulose acetate resins, polyether resins such as polyether resins, and polyamide resins.

Examples of the shape of the semipermeable membrane 12 include a flat membrane, a hollow fiber membrane, and a spiral membrane. Hollow fiber membranes are preferred because the surface area of the semipermeable membrane can be increased.

The second recovery product is the dissolved solid content (TDS) contained in the distilled water, for example, inorganic salts such as sodium sulfate, calcium sulfate, sodium chloride, calcium chloride, etc. may be mentioned.

According to the water treatment method and the water treatment device of this embodiment, it can also be in the front stage of the first recovery step (first recovery means), for example, including: using a precision filtration membrane (MF membrane), an ultrafiltration membrane (UF membrane), etc. The membrane treatment step (membrane treatment means), reverse osmosis membrane treatment step (reverse osmosis membrane treatment means), coagulation precipitation treatment step (coagulation precipitation treatment means), organic matter removal treatment step (organic matter removal treatment means), pH adjustment step (pH adjustment means), a pretreatment step (pretreatment means) of at least one of the water temperature adjustment step (water temperature adjustment means).

For example, pH adjustment and water temperature adjustment may be performed in order to efficiently recover the substance to be recovered by distillation at the front stage of the distillation apparatus 11 . Although it also depends on the water quality of the ammonia-containing water, the concentration conditions of the first recovered product, etc., the pH of the ammonia-containing water is preferably set in the range of 10-12, and the water temperature is preferably set at 30-40°C. scope.

It is also possible to adjust the pH and water temperature again in the rear section of the distillation device 11 and before passing water to the semi-permeable membrane module. The pH and water temperature when passing through the semi-permeable membrane module may depend on the water quality of the ammonia-containing water, the material of the semi-permeable membrane module, and the like. For example, the pH of ammonia-containing water is preferably in the range of 3-8, and the water temperature is preferably in the range of 15-40°C.

For pH adjustment, pH can be adjusted by adding a pH adjuster to a pH adjustment tank, for example. Examples of the pH adjuster include acids such as hydrochloric acid and sulfuric acid, alkalis such as sodium hydroxide, and the like.

For water temperature adjustment, for example, a water temperature adjustment tank can be provided, and heating can be performed in the water temperature adjustment tank by a heating device such as a heater, or a heat exchanger can be provided for adjustment.

The water treatment method and water treatment device according to this embodiment may further include: a water recovery step (water recovery means), after the second recovery step (second recovery means), the water from the second recovery step (second recovery means) recovery means) at least a part of the diluted water discharged from the reverse osmosis membrane is circulated to obtain permeated water; front section. An example of a water treatment device configured in this way is shown in FIG. 8 .

The water treatment device 8 of FIG. 8, in addition to the structure of the water treatment device 1 of FIG. The permeable membrane is passed through to obtain permeate water.

In the water treatment device 8 of FIG. 8 , the outlet of the second space of the membrane module 10 and the inlet of the reverse osmosis membrane treatment device 200 are connected by a pipe 30 . A pipe 202 is connected to the RO permeate outlet of the reverse osmosis membrane treatment device 200 . The RO concentrated water outlet of the reverse osmosis membrane treatment device 200 and the upstream side of the pump 18 in the piping 24 are connected by the piping 204 which is the return means. Other configurations are the same as those of the water treatment device 1 in FIG. 1 . In the water treatment devices 2 to 7 of FIGS. 2 to 7 , a reverse osmosis membrane treatment device 200 and a pipe 204 that is a return means may be provided.

In the water treatment device 8 , the first recovery step and the second recovery step are performed in the same manner as in the water treatment device 1 of FIG. 1 . The dilution water obtained in the second space 16 of the membrane module 10 is sent to the reverse osmosis membrane treatment device 200 through the pipe 30 . In the reverse osmosis membrane treatment device 200, reverse osmosis membrane treatment is performed using a reverse osmosis membrane to obtain RO concentrated water and RO permeated water (water recovery step). The obtained RO permeate water can be discharged out of the system through the pipe 202 and reused. The RO concentrated water system is sent back to the front stage of the membrane module 10, such as the pipe 24, through the pipe 204 to be mixed with the distilled water (return step). The RO concentrated water can also be sent back to the front stage of the distillation unit 11 to be mixed with the ammonia-containing water.

As described above, at least one of ammonia and ammonium ions is recovered as the first recovered product from the ammonia-containing water that is the object of treatment, and furthermore, the concentrated water after the ions are concentrated is recovered as the second recovered product. , to reduce the volume of ammonia-containing water. The first recyclables and the second recyclables can be reused. In addition, by further treating the dilution water with a reverse osmosis membrane, it can be made into a water quality more suitable for reuse. By sending RO concentrated water back to the front stage of the semi-permeable membrane module, the amount of drainage can be reduced.

1,2,3,4,5,6,7,8: water treatment device 10,10a,10b,10c: membrane module 11: Distillation device 12, 12a, 12b, 12c: semi-permeable membrane 14,14a,14b,14c: the first space 16, 16a, 16b, 16c: the second space 1:8 pump 20: Inverter 22,22a,22b,22c,23,32,32a,32b,32c: Valve 24,25,26,27,28,29,30,34,36,40,42,44,46,48,50,52,54,56,58,64,66,68,70,72,74, 76,78,80,82,88,90,92,94,96,98,102,104,106,108,110,112,114,116,118,120,122,124,126,202,204: Piping 60a, 60b, 60c, 62a, 62b, 62c: dilution tank 84: Distillation treatment tank 86: concentrated sink 100, 100a, 100b, 100c, 100d: membrane module unit 200: reverse osmosis membrane treatment device

Fig. 1 is a schematic configuration diagram showing an example of a water treatment device according to an embodiment of the present invention. Fig. 2 is a schematic configuration diagram showing another example of a water treatment device according to an embodiment of the present invention. Fig. 3 is a schematic configuration diagram showing another example of the water treatment device according to the embodiment of the present invention. Fig. 4 is a schematic configuration diagram showing another example of the water treatment device according to the embodiment of the present invention. Fig. 5 is a schematic configuration diagram showing another example of the water treatment device according to the embodiment of the present invention. Fig. 6 is a schematic configuration diagram showing another example of the water treatment device according to the embodiment of the present invention. Fig. 7 is a schematic configuration diagram showing another example of the water treatment device according to the embodiment of the present invention. Fig. 8 is a schematic configuration diagram showing another example of the water treatment device according to the embodiment of the present invention.

1: Water treatment device

10: Membrane module

11: Distillation device

12: Semi-permeable membrane

14: The first space

16:Second space

18: pump

20: Inverter

22,23: valve

24,25,26,27,28,30: Piping

Claims (8)

A water treatment method is to recover valuables from ammonia-containing water, which includes the following steps: In the first recovery step, at least one of ammonia and ammonium ions is recovered from the ammonia-containing water by a distillation device as a first recovered product; and In the second recovery step, by using a semipermeable membrane module having a first space and a second space separated by a semipermeable membrane, the distilled water of the distillation device is passed through the first space, and the first space is pressurized A space allows the water contained in the distilled water to permeate the semi-permeable membrane to obtain a second recovered product as concentrated water, and at the same time, a part of the distilled water or at least a part of the concentrated water flows through the second space, so that Get dilution water. A water treatment method is to recover valuables from ammonia-containing water, which includes the following steps: In the first recovery step, at least one of ammonia and ammonium ions is recovered from the ammonia-containing water by a distillation device as a first recovered product; and The second recovery step is by using a semi-permeable membrane module connected with multiple sections of the first space and the second space separated by a semi-permeable membrane, and circulating the first space of the first section of the semi-permeable membrane module The distilled treatment water of the distillation device, and pressurize the first space so that the water contained in the distilled treated water permeates the semi-permeable membrane to obtain concentrated water, and then use the semi-permeable membrane module after the next stage to dilute the concentrated water Further obtain the second recovered product as concentrated water, and at the same time pass a part of the distilled water or at least a part of the concentrated water to the second space of each semi-permeable membrane module or obtain it from other semi-permeable membrane modules At least a part of the dilution water to obtain the dilution water. The water treatment method as described in claim 1 or 2 further comprises the following steps: a water recovery step, after the second recovery step, circulating at least a portion of the dilution water discharged from the second recovery step to a reverse osmosis membrane to obtain permeate water; and In the returning step, the concentrated water discharged from the reverse osmosis membrane is returned to the front section of the semi-permeable membrane module. The water treatment method as described in Claim 1 or 2, wherein, In the ammonia-containing water, the sulfate ion concentration is above 6000 mg/L, and the ammonium ion concentration is above 2000 mg/L. A water treatment device recovers valuables from ammonia-containing water, comprising: The first recovery means is to recover at least one of ammonia and ammonium ions from the ammonia-containing water as a first recovery product by means of a distillation device; and The second recovery means is to use a semi-permeable membrane module having a first space and a second space separated by a semi-permeable membrane, and flow the distilled water of the distillation device through the first space, and pressurize the first space. A space allows the water contained in the distilled water to permeate the semi-permeable membrane to obtain a second recovered product as concentrated water, and at the same time, a part of the distilled water or at least a part of the concentrated water flows through the second space, so that Get dilution water. A water treatment device recovers valuables from ammonia-containing water, comprising: The first recovery means is to recover at least one of ammonia and ammonium ions from the ammonia-containing water as a first recovery product by means of a distillation device; and The second recovery method is to use a semi-permeable membrane module connected by multiple sections of the first space and the second space separated by a semi-permeable membrane, and circulate the first space of the first section of the semi-permeable membrane module. The distilled treatment water of the distillation device, and pressurize the first space so that the water contained in the distilled treated water permeates the semi-permeable membrane to obtain concentrated water, and then use the semi-permeable membrane module after the next stage to further dilute the concentrated water As concentrated water, the second reclaimed product is obtained, and at the same time, a part of the distilled water or at least a part of the concentrated water is circulated in the second space of each semi-permeable membrane module, or obtained from other semi-permeable membrane modules At least a part of the dilution water to obtain the dilution water. The water treatment device as described in Claim 5 or 6, further comprising: Water recovery means, after the second recovery means, circulates at least a part of the dilution water discharged from the second recovery means to the reverse osmosis membrane to obtain permeate water; and The return means is to return the concentrated water discharged from the reverse osmosis membrane to the front section of the semi-permeable membrane module. The water treatment device as described in Claim 5 or 6, wherein, In the ammonia-containing water, the sulfate ion concentration is above 6000 mg/L, and the ammonium ion concentration is above 2000 mg/L.

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