JP6747893B2 - Liquid processing apparatus and liquid processing method - Google Patents

Description

The present invention relates to a treatment device and a treatment method for a liquid containing a solid content.

As a method for performing solid-liquid separation of a liquid containing solids, a membrane filtration treatment using a microfiltration membrane (MF membrane), an ultrafiltration membrane (UF membrane) or the like is used in water purification treatment or the like. Membrane filtration devices such as microfiltration membranes and ultrafiltration membranes can separate solids in the liquid to be treated, but cannot separate dissolved components such as organic substances. Further, it is known that these organic components cause film clogging, and if the liquid to be treated contains a high concentration of organic substances, it may be necessary to frequently clean the film with chemicals. Further, when microorganisms such as bacteria are mixed in the liquid to be treated, biodeterioration may occur depending on the material of the membrane, and a predetermined solid-liquid separation performance may not be obtained.

An ultraviolet (UV) lamp may be used for sterilization of bacteria contained in a liquid and oxidative decomposition of organic substances. However, since the ultraviolet lamp has a restriction on the shape of the lamp itself and an electrode is indispensable, incorporating a conventional ultraviolet lamp in the membrane filtration device is effective in terms of efficient light irradiation from the viewpoint of the device configuration. It is also extremely difficult from the point of view, and the ultraviolet irradiation device is generally installed separately from the membrane filtration device.

On the other hand, a microwave ultraviolet light emitting device is known as one of the ultraviolet irradiation devices. For example, there is one in which a granular electrodeless ultraviolet luminescent material is externally irradiated with a microwave of 2.45 GHz or the like to emit ultraviolet light (see, for example, Patent Document 1 and Non-Patent Document 1).

Japanese Patent No. 5049004

Satoshi Horikoshi, "Study on development of contaminated water purification device in disaster area using photocatalyst-coated electrodeless lamp", March 2014, FY2013 Environmental Research Comprehensive Expenses Subsidy Research Project General Research Report

An object of the present invention is to provide a liquid processing apparatus and a liquid processing method including a module-type membrane filtration device capable of performing an ultraviolet irradiation process as well as a separation process of a liquid containing a solid content.

The present invention is provided with a module type membrane filtration device having a filtration membrane, in which a granular luminescent material that emits ultraviolet rays by microwaves is filled, and a microwave generation means, and the generation is performed by the microwave generation means. While irradiating the microwave to the granular light-emitting body, the liquid to be treated containing solids is passed through the membrane filtration device, and the solid-liquid separation treatment of the solids of the liquid to be treated is performed together with the ultraviolet irradiation treatment. It is a liquid processing device.

In the liquid processing apparatus, the filtration membrane is preferably a ceramic membrane.

In the liquid processing apparatus, the filtration membrane is preferably an external pressure type.

It is preferable that the liquid processing apparatus includes a photocatalyst adding unit that adds a suspension-type photocatalyst to the liquid to be processed.

Further, the present invention provides the granular light-emitting body in a module type membrane filtration device having a filtration membrane for the microwave generated by the microwave generation means and having a granular light-emitting body which emits ultraviolet rays by the microwave filled therein. While irradiating the liquid, a liquid to be treated containing solids is passed through the membrane filtration device, and a liquid treatment method including a treatment step of performing solid-liquid separation treatment of the solids of the liquid to be treated and ultraviolet irradiation treatment. is there.

In the liquid treatment method, the filtration membrane is preferably a ceramic membrane.

In the liquid treatment method, it is preferable that the filtration membrane is of an external pressure type.

It is preferable that the liquid treatment method further includes a photocatalyst addition step of adding a suspension photocatalyst to the liquid to be treated.

ADVANTAGE OF THE INVENTION According to this invention, it becomes possible to provide the liquid treatment apparatus and liquid treatment method provided with the module type membrane filtration apparatus which can perform the ultraviolet irradiation process with the separation process of the liquid containing solid content.

It is a schematic structure figure showing an example of a liquid treatment equipment concerning an embodiment of the present invention. It is a schematic block diagram which shows the liquid processing apparatus used in the comparative example.

Embodiments of the present invention will be described below. The present embodiment is an example for carrying out the present invention, and the present invention is not limited to this embodiment.

An outline of an example of a liquid processing apparatus according to an embodiment of the present invention is shown in FIG. 1, and its configuration will be described.

The liquid treatment apparatus 1 according to the present embodiment has a filter type membrane 36, and a module type membrane filtration apparatus 12 in which a granular light-emitting body 34 that emits ultraviolet rays by microwaves is filled, and a microwave generation means for generating a microwave. The wave generator 14 is provided. The liquid processing apparatus 1 may include a processed liquid tank 10 for storing a processed liquid and a processing liquid tank 16 for storing a processed liquid.

In the liquid treatment apparatus 1 of FIG. 1, the outlet of the treated liquid tank 10 and the lower inlet of the membrane filtration device 12 are connected by a treated liquid pipe 20 via a pump 18. The treatment liquid outlet on the upper part of the membrane filtration device 12 and the inlet of the treatment liquid tank 16 are connected by a treatment liquid pipe 22. The concentrated liquid outlet of the membrane filtration device 12 and the liquid tank 10 to be treated are connected by a circulation pipe 24. At least one filtration membrane 36 is installed inside the membrane filtration device 12, and the space is filled with at least one granular luminous body 34. In the membrane filtration device 12, at least one microwave generation device 14 is installed as a microwave generation means so that the granular light-emitting body 34 inside the membrane filtration device 12 can be irradiated with microwaves. A photocatalyst addition pipe 38 may be connected to the upper portion of the liquid tank 10 to be treated as a photocatalyst addition means for adding a suspension photocatalyst to the liquid to be treated.

The operation of the liquid processing method and the liquid processing apparatus 1 according to this embodiment will be described.

While activating the microwave generation device 14 and irradiating the generated microwaves to the granular light-emitting bodies 34 in the membrane filtration device 12, the pump 18 from the liquid tank 10 to be treated causes the liquid to be treated containing solids to be treated. It is supplied to the inside from the lower inlet of the membrane filtration device 12 through the treatment liquid pipe 20. As a result, in the membrane filtration device 12, the filtration membrane 36 performs the solid-liquid separation treatment of the liquid to be treated containing the solid content and the ultraviolet irradiation treatment (treatment step). The treatment liquid after passing through the filtration membrane 36 is discharged from the treatment liquid outlet in the upper part of the membrane filtration device 12 and transferred to the treatment liquid tank 16 through the treatment liquid pipe 22. The concentrated liquid from the membrane filtration device 12 may be circulated to the liquid tank 10 to be treated through the circulation pipe 24.

In the solid-liquid separation process, the filtration membrane 36 separates solids from the liquid to be processed. Thereby, the turbidity of the treatment liquid can be reduced.

In the ultraviolet irradiation treatment, the ultraviolet rays emitted from the granular light-emitting body 34 by the microwave irradiation mainly perform sterilization treatment of bacteria and oxidative decomposition treatment of organic substances and the like by photooxidation of ultraviolet rays.

With the liquid processing method and the liquid processing apparatus according to the present embodiment, the module type membrane filtration apparatus can perform the ultraviolet irradiation processing together with the solid-liquid separation processing of the liquid containing the solid content. Moreover, by performing both the solid-liquid separation process and the ultraviolet irradiation process, the installation area of the liquid processing apparatus can be reduced.

The inside of the module is filled with the granular light-emitting body 34 that emits ultraviolet light by microwaves, and the microwave generator 14 that irradiates the granular light-emitting body 34 with microwaves is installed outside the module. Ultraviolet irradiation treatment such as sterilization treatment of bacteria and oxidative decomposition treatment of organic substances is performed. By filling the inside of the module with a granular light-emitting body 34 that emits ultraviolet light at a high density, and by causing it to emit light by microwave irradiation from the outside, it is possible to efficiently achieve sterilization treatment and oxidative decomposition treatment of organic substances. It is possible to reduce clogging and deterioration of the filtration membrane and to improve the treatment liquid quality, as compared with a conventional system in which a filter and a membrane filtration device are combined. Further, since the sterilization process, the oxidative decomposition process, and the solid-liquid separation process can be performed by one device, it is possible to significantly reduce the installation space as compared with the conventional system.

The liquid to be treated to be treated is not particularly limited as long as it is a liquid containing a solid content. Examples of the liquid include water and sugar liquid. Examples of the solid content include suspended substances. The liquid to be treated has a turbidity of, for example, 0.1 degree or more and 100 degrees or less, a chromaticity of, for example, 0.5 degree or more and 100 degrees or less, and a TOC of, for example, 0.1 mg/L or more and 100 mg/L or less. The number of bacteria is, for example, 100/mL or more and 100,000/mL or less.

The membrane filtration device 12 is a module-type membrane filtration device, and may be a pressure type membrane filtration device having a filtration membrane sealed in a cylindrical container (casing) such as a cylinder in a filtration tank inside the membrane filtration device. There is no particular limitation.

There is no particular limitation on the material constituting the microwave irradiation surface of the membrane filtration device 12 as long as it is a material that transmits microwaves. For example, quartz glass, polytetrafluoroethylene (Teflon (registered trademark)) , Polystyrene, polyether ether ketone (PEEK), ceramics and the like.

The liquid to be treated in the membrane filtration device 12 is usually supplied from the lower portion of the membrane filtration device 12 as shown in FIG. 1, but may be supplied from the upper portion or the side surface of the membrane filtration device 12. ..

The filtration membrane 36 is not particularly limited as long as it is a pressure type filtration membrane capable of performing a solid content separation process. Examples of the filtration membrane 36 include a microfiltration membrane (MF membrane), an ultrafiltration membrane (UF membrane), and a large pore diameter membrane (LP membrane).

Examples of the material of the filtration membrane 36 include an organic membrane or an inorganic membrane. Examples of the organic film include cellulose acetate (CA) film, polyethylene (PE) film, polypropylene (PP) film, polyacrylonitrile (PAN) film, polystyrene (PS) film, polyether sulfone (PES) film, and polyvinylidene. Examples thereof include a dendifluoride (PVDF) film and a polytetrafluoroethylene (PTFE) film. Examples of the inorganic film include ceramic films of alumina, titania, zirconia, and the like. From the viewpoint of UV resistance and strength, an inorganic film is preferable, and a ceramic film is more preferable.

Examples of the form of the filtration membrane 36 include a tubular membrane, a hollow fiber membrane, and the like. The tubular membrane is preferable because it is difficult to install the granular light-emitting body 34 in the hollow fiber by the internal pressure method.

The water flow system of the filtration membrane 36 may be either an internal pressure system or an external pressure system, but the external pressure system is preferable in that the granular light emitting bodies 34 can be efficiently arranged.

The microwave generator 14 only needs to be capable of generating microwaves (frequency: for example, 2.450 GHz±0.05 GHz, 5.800 GHz±0.075 GHz, 24.125 GHz±0.125 GHz), The structure is not particularly limited. For example, in addition to the magnetron method using a vacuum tube, a solid state method using a semiconductor may be used. Magnetron oscillators are widely used in household and commercial microwave ovens and have the advantage that they can be obtained at a relatively low price.Solid state oscillators have a relatively long life and good wavelength stability. There are some advantages.

As an example of the configuration of the microwave generation device 14, for example, as shown in FIG. 1, a configuration including a power supply device 26, a microwave oscillator 28, a waveguide 30, and a stub tuner 32 may be mentioned.

For example, by the power supplied from the power supply device 26, the microwave generated by the microwave oscillator 28 passes through the waveguide 30 and is applied to the granular light emitter 34 in the membrane filtration device 12. The three-stub tuner 32 allows the impedance matching in the waveguide 30 to be adjusted. The microwave generation device 14 may include a short-circuit device (not shown) on the opposite side of the waveguide 30 that sandwiches the membrane filtration device 12.

The microwave irradiation may be performed from one direction in which the membrane filtration device 12 is provided, or may be performed from two or more directions. When the diameter of the membrane filtration device 12 becomes large (for example, 30 cm or more), the microwave may not reach the central portion, so it is preferable to irradiate the membrane filtration device 12 from two or more directions.

The granular light-emitting body 34 may be anything that emits ultraviolet rays (for example, light having a wavelength of 100 nm to 400 nm) by microwaves, and in addition to ultraviolet rays, visible light (for example, light having a wavelength of 400 nm to 780 nm) or infrared rays (for example, wavelength 780 nm). There is no particular limitation depending on the presence/absence of generation of light of 1 mm). The granular light-emitting body 34 is made of, for example, quartz or Teflon (registered trademark) resin, which has a small absorption of ultraviolet rays, and is made of fluororesin, and has a spherical shape or a capsule-shaped container in which both ends of a cylinder are spherical. Electrode-free ultraviolet light emission in which a discharge gas, such as mercury gas, hydrogen gas, xenon gas, nitrogen gas, argon gas, helium gas, chlorine gas, fluorine gas, deuterium gas, etc., which emits ultraviolet light by microwaves, is enclosed at a specified enclosure pressure. Examples include capsules and the like. By irradiating microwaves to the electrodeless ultraviolet light emitting capsule in which the discharge gas is sealed, the gas is excited and emits ultraviolet light. The emission wavelength can be adjusted by appropriately selecting the discharge gas and the filling pressure. Further, in order to adjust the specific gravity of the capsule, a hollow or solid protruding specific gravity adjusting portion formed of the same material as the capsule may be provided at both ends or one end of the capsule.

When the granular luminescent material 34 has a spherical shape, the maximum diameter is, for example, in the range of 1.0 mm to 10 mm, preferably in the range of 2.0 mm to 4.0 mm. When the granular luminescent material 34 is in the shape of a capsule in which both ends of a cylinder are spherical, the diameter is, for example, in the range of 1.0 mm to 10 mm, preferably in the range of 2.0 mm to 4.0 mm, and the height is For example, the range is 2.0 mm to 20 mm, and the range is preferably 4.0 mm to 8.0 mm.

The specific gravity adjusting portion has a diameter of, for example, 1.0 mm to 10 mm, preferably 2.0 mm to 4.0 mm, and a height of, for example, 2.0 mm to 20 mm. It is preferably in the range of 4.0 mm to 10 mm.

The emission wavelength of the granular illuminant 34 may be appropriately selected according to the types of organic substances and bacteria to be treated and is not particularly limited. When the oxidative decomposition treatment of organic substances is mainly performed, a granular luminescent material that emits ultraviolet rays having a wavelength of 185±0.1 nm or 220±0.1 nm is usually used, and the sterilization treatment of bacteria is mainly performed. Usually, a granular luminescent material that emits ultraviolet rays having a wavelength of 254±0.7 nm or 260±0.7 nm is used.

As the granular luminescent material 34, two or more types of granular luminescent materials having different emission wavelengths may be used. The filling ratio of the two or more types of granular luminescent materials having different emission wavelengths is not particularly limited and may be appropriately changed according to the quality of the liquid to be treated and the like. Since microwaves are easily absorbed by water, excessive output may be given to the granular luminescent material, resulting in a large energy loss. By using two or more types of granular luminescent materials having different emission wavelengths and appropriately changing the filling ratio, both of organic substances and bacteria can be controlled to have a predetermined removal rate or a predetermined treatment liquid concentration. The dose can be adjusted appropriately, and it is efficient in terms of power consumption.

Before the liquid to be treated is supplied to the membrane filtration device 12, a suspension photocatalyst may be added to the liquid to be treated, for example, through the photocatalyst addition pipe 38. When a suspension-type photocatalyst is added to the liquid to be treated, accelerated oxidation by the photocatalyst occurs in addition to the ultraviolet oxidation, so that the quality of the treated liquid can be further improved and the clogging and deterioration of the film can be suppressed. The added suspension-type photocatalyst is subjected to solid-liquid separation in the membrane filtration device 12. The suspension-type photocatalyst may be added in the liquid tank 10 to be treated, may be carried out in the liquid pipe 20 to be treated, and may be separately provided between the liquid tank 10 to be treated and the membrane filtration device 12. An intermediate tank may be provided and the operation may be performed in the intermediate tank.

Examples of suspension photocatalysts include inorganic photocatalysts such as titanium dioxide (TiO ₂ ), zinc oxide (ZnO), and strontium titanate (SrTiO ₃ ).

The amount of the suspension photocatalyst added is, for example, in the range of 10 to 10,000 mg/L.

For example, when the discharge amount of the treatment liquid from the membrane filtration device 12 decreases, the inside of the membrane filtration device 12 may be washed by backwashing (backwashing).

Liquid treatment method and liquid treatment apparatus according to the present embodiment, when performing both solid-liquid separation in water purification treatment, sewage treatment, industrial water treatment, wastewater treatment, etc., ultraviolet sterilization, ultraviolet irradiation treatment such as ultraviolet oxidation treatment. It can be applied, and in particular, can be suitably applied to water purification treatment.

With the liquid treatment method and the liquid treatment apparatus according to the present embodiment, for example, the turbidity is 1.5 degrees or more, the chromaticity is 3.0 degrees or more, the TOC is 2.0 mg/L or more, and the number of bacteria is 2,000/ For example, the turbidity is 0.1 degree or less, the chromaticity is 0.5 degree or less, the TOC is 1.0 mg/L or less, and the number of bacteria is 1 piece/mL or less. Can be

Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples, but the present invention is not limited to the following Examples.

<Example 1 and Comparative Example 1>
In Example 1, the liquid treatment apparatus 1 shown in FIG. 1 was used, and in Comparative Example 1, the liquid treatment apparatus 3 shown in FIG. 2 was used. The liquid processing apparatus 3 of FIG. 2 includes a liquid tank 50 to be treated, an ultraviolet irradiation device 52, a membrane filtration device 54 having a filtration membrane 58, and a treatment liquid tank 56.

The test was conducted under the following device specifications and water flow conditions.
[Water flow conditions]
Flow rate: 40L/h
[Device configuration]
(Comparative Example 1)
Ultraviolet irradiation device: low pressure ultraviolet lamp (SGL1000N) manufactured by DN Lighting Co., Ltd. Lamp wavelength 185,254 nm
Membrane Filtration Device: External Pressure Type Tubular Membrane Filtration Device Tubular Membrane (Material: Ceramic MF Membrane) φ10 mm×H1000 mm 10 Filtration Tank Body: φ80 mm×H1200 mm
(Example 1)
Membrane Filtration Device: External Pressure Type Tubular Membrane Filtration Device Tubular Membrane (Material: Ceramic MF Membrane) 10 φ10 mm x H1000 mm Filtration Tank Main Body: φ80 mm x H1200 mm, Material Teflon (registered trademark) 2.2L filling

[Details of UV luminescent granular luminescent material (electrodeless UV luminescent capsule)]
・Size: Diameter (φ) 5 mm × Height (L) 10 mm
・Material: Quartz ・Filled gas: Mercury gas, filled pressure 10Pa
・Peak wavelength: 185 nm, 254 nm

[Microwave generator]
・Power supply device: 300W (30-300W variable type)
・Microwave oscillator: magnetron ・Frequency: 2.45 GHz
-Waveguide: L400mm x W55mm x H109mm, made of aluminum-Tuner: Three-stub system

The input power of the power supply of the microwave generator was set to 60W. Table 1 shows the water quality (turbidity, chromaticity, TOC) of the liquid to be treated and the treatment liquid, and the transmembrane pressure increase rate. The turbidity and chromaticity were measured using WA6000 type (manufactured by Nippon Denshoku Co., Ltd., turbidity measurement was an integrating sphere method, and chromaticity measurement was a 390 nm transmitted light measurement method method). The TOC was measured by a combustion method using a TOC meter (TOC500 manufactured by Shimadzu Corporation). The experimental results are shown in Table 1.

As described above, in the liquid treatment device including the module-type membrane filtration device of the example, the ultraviolet irradiation treatment could be performed together with the separation treatment of the liquid containing the solid content.

By carrying out both the solid-liquid separation treatment, the ultraviolet sterilization treatment, and the ultraviolet oxidative decomposition treatment, the installation area of the treatment device could be reduced by about 40%. Further, it is possible to reduce clogging and deterioration of the filtration membrane, and it is possible to improve the treatment liquid quality (chromaticity, TOC).

1,3 Liquid treatment device, 10,50 Treatment liquid tank, 12,54 Membrane filtration device, 14 Microwave generator, 16,56 Treatment liquid tank, 18 Pump, 20 Treatment liquid pipe, 22 Treatment liquid pipe, 24 Circulation piping, 26 power supply device, 28 microwave oscillator, 30 waveguide, 32 stab tuner, 34 granular luminescent material, 36, 58 filtration membrane, 38 photocatalyst added piping, 52 UV irradiation device.

Claims (8)

A module type membrane filtration device having a filtration membrane and having a granular luminescent material that emits ultraviolet light by microwaves filled inside,
Microwave generation means,
Equipped with
While irradiating the granular light-emitting body with microwaves generated by the microwave generation means, a liquid to be treated containing solids is passed through the membrane filtration device to obtain a solid liquid of the solids of the liquid to be treated. A liquid processing apparatus, which performs ultraviolet irradiation processing together with separation processing. The liquid processing apparatus according to claim 1, wherein
A liquid treatment apparatus, wherein the filtration membrane is a ceramic membrane. The liquid processing apparatus according to claim 1 or 2, wherein
The liquid treatment apparatus, wherein the filtration membrane is an external pressure type. The liquid processing apparatus according to any one of claims 1 to 3,
A liquid processing apparatus comprising photocatalyst adding means for adding a suspension photocatalyst to the liquid to be processed. While irradiating the microwave generated by the microwave generation means to the granular light-emitting device in a module type membrane filtration device having a filtering film, and the granular light-emitting device emitting ultraviolet light by the microwave is filled inside, A liquid treatment method, comprising a treatment step of causing a liquid to be treated containing a component to pass through the membrane filtration device, and performing solid-liquid separation treatment of the solid content of the liquid to be treated and ultraviolet irradiation treatment. The liquid processing method according to claim 5, wherein
The liquid treatment method, wherein the filtration membrane is a ceramic membrane. The liquid processing method according to claim 5 or 6, wherein
The liquid treatment method, wherein the filtration membrane is an external pressure type. The liquid processing method according to any one of claims 5 to 7,
The liquid treatment method further comprising a photocatalyst addition step of adding a suspension photocatalyst to the liquid to be treated.