JP4280846B2 - Underwater metal component adsorption device and recovery device - Google Patents

Description

  TECHNICAL FIELD The present invention relates to an adsorption device and recovery device for metal components in water, and more particularly, an adsorption and recovery device for metal components (metal ions) contained in groundwater or industrial wastewater, etc., having chelate functional groups and ion exchange on the surface. The present invention relates to an adsorption and recovery device using a non-woven fabric filter having a metal collecting property in which a functional group or the like is formed.

  Water is passed through a packed bed filled with a metal-capturing nonwoven filter in which a chelate functional group such as an iminodiacetic acid group is introduced by graft polymerization of a monomer to a polymer substrate such as an olefin polymer, particularly a nonwoven fabric substrate. Various techniques for collecting and adsorbing metal components (metal ions) have been proposed (see, for example, Patent Documents 1, 2, 3, and 4).

Also known is a technique of collecting and adsorbing a metal component with a nonwoven fabric filter in which a core-sheath composite fiber is used for a nonwoven fabric substrate and an ion exchange group or a chelate functional group is formed (Patent Documents 5 and 6). Further, an underwater immersion type metal collecting device in which chelate-functional nonwoven fabrics and spacers are alternately stacked has been proposed (see Patent Document 7).
JP-A-2-187143 JP-A-5-57280 Japanese Patent Laid-Open No. 5-57281 JP-A-9-253646 JP-A-8-199480 Japanese Patent Laid-Open No. 2000-178531 JP 2000-308886 A

  Based on the above prior art, the present invention is a compact and efficient adsorption with a simple structure that efficiently collects, adsorbs and recovers metal components, such as Mn (manganese) and Fe (iron), contained in groundwater and well water. An apparatus and a recovery apparatus are provided.

  The adsorbing device of the present invention is an underwater metal component adsorbing device in which a nonwoven fabric filter having a metal-capturing functional group formed on a surface and a spacer are laminated, and a spacer having a net-like permeation hole in a column container. A nonwoven fabric filter is laminated to form a packed bed, and the raw water is allowed to pass through the packed bed to adsorb and remove metal components in the raw water.

  In addition, a spacer is formed by crossing and joining parallel parallel stripes to form a mesh-like transmission hole, and the spacer has a mesh-like transmission hole formed by a support portion of the filter and a wire portion connecting the support portion. , One in which the thickness of the linear portion is smaller than the thickness of the support portion, the spacer is a plastic molded product, the nonwoven fabric filter is made larger than the spacer, the inner wall of the column container is sealed at the end of the filter, and the nonwoven fabric filter is What consists of a composite fiber formed from a highly reactive sheath and a core having strength, and a non-woven fabric consisting of a composite fiber whose sheath is PE and whose core is PP, and has a chelate functional group formed by graft polymerization Include.

  The recovery device of the present invention has the above-described adsorption device and a recovery cleaning liquid tank, and passes the recovery cleaning liquid through the adsorption device, dissolves the adsorbed metal component in the recovery cleaning liquid, and concentrates to recover the metal component. It is characterized by.

  With the above configuration, the adsorption / recovery device of the present invention increases the contact area between the treated water and the non-woven filter having a metal collecting property such as chelate functionality, reduces the liquid flow resistance, and increases the packing density of the non-woven filter. The metal component can be adsorbed and recovered efficiently with a compact and simple structure (high processing speed and a large amount of processing up to breakthrough).

  Embodiments of the present invention will be described below with reference to the drawings. 1 is a front sectional view schematically showing an embodiment of an adsorption device, FIG. 2 is a detailed view of a portion X in FIG. 1, FIG. 3 is a schematic perspective view of a spacer, and FIG. 4 is a schematic diagram of another example of the spacer. FIG. 5 is a schematic perspective view of another example of the spacer, and FIG. 6 is a schematic flow diagram of the recovery apparatus of the present invention.

  In FIG. 1, reference numeral 10 denotes a cylindrical column container which is a main body of the adsorption device, and both end portions thereof are conically narrowed. Reference numerals 11 and 12 denote flanges for pipe connection attached to both ends of the column container, and reference numerals 13 and 14 denote upper and lower annular support bases fixed to the inner wall of the column container 10. Reference numeral 20 denotes a packed layer, 30 denotes a spacer, and 40 denotes a nonwoven fabric filter. The spacer 30 and the nonwoven fabric filter 40 are alternately stacked in the column container 10 to form the packed layer 20.

  As shown in FIG. 3, the spacer 30 is formed by punching a plate-like plastic molded body having a large number of mesh-like transmission holes H in a circular shape in a form in which parallel strips 31 and 32 are crossed and joined vertically. Is. The nonwoven fabric filter 40 is made of a composite fiber having a core-sheath structure, the core part is made of polypropylene (PP), the sheath part is made of polyethylene (PE), and after graft polymerization of a reactive monomer on the surface PE (sheath part), It is a chelate-functional non-woven fabric introduced with a chelate functional group.

  The nonwoven fabric filter 40 has a size that protrudes beyond the spacer 30. When the packed layer 20 is formed in the column container 10, the nonwoven fabric filter 40 is stretched to cover the end face of the spacer 30 without sagging, and cover the lower surface. The spacer 30 and the nonwoven fabric filter 40 are sequentially laminated on the support table 13 in the same manner. The upper end of the packed bed 20 is pressed by the upper support 14. The filling layer 20 is held so as to be sandwiched between the upper and lower support bases 13 and 14 in a compressed state with flexibility of the plastic spacer 30, compressibility of the nonwoven fabric filter 40, and flexibility.

  When raw water (ground water, industrial waste water, etc.) containing metal components (metal ions) is treated with this adsorption device, inflow piping and outflow piping (not shown) are connected to the upper and lower flanges 11 and 12 of the adsorption device. The raw water is permeated through the packed bed 20 in an upward flow or a downward flow to collect, adsorb and remove metal components in the water on the chelate functional groups on the surface of the nonwoven fabric filter 40.

  When the metal component is adsorbed and the packed bed 20 breaks through, a cleaning liquid such as hydrochloric acid is passed from the recovered cleaning liquid tank T connected to the adsorption tower F as shown in FIG. The components are dissolved and the recovered liquid is stored in the recovery tank R, which is concentrated to recover the metal components and wash the nonwoven fabric filter. In FIG. 6, P1 is a raw water feed pump, P2 is a recovered cleaning liquid feed pump, and A is a treated water discharge tank.

  In the adsorption device described above, the spacer 30 is a net-like body in which the parallel strips 31 and 32 are crossed and joined one above the other so that the contact portion between the nonwoven fabric filter 40 and the spacer 30 is located above and below. It is limited to the contact part with any of the filaments, does not contact the filaments located downstream in the flow direction, allows a large permeation area, and allows a liquid flow along the surface of the nonwoven fabric filter 40 to flow. Resistance becomes smaller.

  The nonwoven fabric filter 40 is made of a composite fiber having a core-sheath structure, the core part is made of polypropylene (PP), the sheath part is made of polyethylene (PE), and a reactive monomer is graft-polymerized to the PE on the surface (sheath part). Then, chelate functional groups are introduced. Since the graft polymerization is carried out on the PE layer on the surface which is easy to react, the density of reactive groups is high, and thus the density of chelate groups is high. The core portion is made of strong PP, and the strength and rigidity of the nonwoven fabric filter are ensured. As a result, the thickness of the nonwoven fabric is reduced, the packing density of chelate functional groups is high, and the adsorptivity is high.

  Regarding the degree of orientation of PE, it is desirable to lower the degree of orientation within a range where the required strength can be maintained to improve the reactivity and increase the graft ratio. Moreover, about a nonwoven fabric, not only a composite fiber but the nonwoven fabric which has the water permeability of the filter specification which can introduce | transduce a metal scavenging functional group can be used.

  In the above-described embodiment, the spacer 30 is shown by punching the mesh made of the filaments 31 and 32 having a uniform diameter (thickness) into a circle, but the contact area with the nonwoven fabric filter is further reduced, and the transmission area is reduced. In order to further increase the permeation resistance, as shown in FIG. 4, a net-like permeation hole H is formed by the support part S of the spherical filter and the line part L connecting the support part S. A net-like body whose thickness (diameter) is smaller than the thickness (diameter) of the support portion S can also be used. In the example shown in the figure, a spherical support portion and a triangular transmission hole are shown. No.

  In the case of a spherical support portion, the contact area with the nonwoven fabric filter can be reduced and the transmission area can be increased, but it is necessary to match the contact points of the upper and lower spacers. In order to facilitate the lamination of the spacer and the non-woven fabric filter, that is, the formation of the filling layer, the support portion can be made flat such as a cube.

  Furthermore, in the above-mentioned example, the end face of the spacer 30 is wrapped with the nonwoven fabric filter 40 to ensure the seal between the inner wall of the column container and the packed layer (nonwoven fabric filter) with the nonwoven fabric filter 40 (to prevent a liquid short path). As shown in FIG. 5, the inner wall of the column can be sealed by using a spacer 30A provided with a rim 33 preferably having elasticity around the circular mesh.

  The column container of the illustrated embodiment has a circular cross section, but the container shape is not limited to a cylindrical shape, and may take an appropriate shape as necessary. In addition, as a method for holding the packed bed in which the nonwoven fabric filter and the spacer are laminated in the column container, a simple method in which the packed layer is sandwiched between upper and lower support bases attached to the inner wall of the column container has been shown. The fixing method is not limited to this, and for example, an appropriate means such as an annular frame that can be screwed to the column container, a strong metal porous plate, or a method of holding the packed layer with a mesh plate can be used.

Radiation to non-woven fabric (manufactured by Kurashiki Fiber Processing Co., Ltd., model number EX02, fineness 0.9 denier, basis weight 50 g / m ² , thickness 0.5 mm) manufactured from melt-blown composite fibers composed of PP and PE Irradiation is performed to generate reaction active sites, and glycidyl methacrylate (5%) is reacted with a solution of methanol (95%) for 30 minutes at 40 ° C. to form a graft chain on the nonwoven fabric. Was reacted at 80 ° C. for 12 hours to produce a chelate-functional non-woven fabric having a graft rate of 150% and an iminodiacetic acid group density of 3 mmol / g. And having rhombus-shaped permeation holes) to form a packed layer. The apparent volume of the packed bed (filter) is 94 cm ³ .

  FIG. 7 shows the breakthrough curve of Fe and FIG. 8 shows the breakthrough curve of Mn when the well water (containing 1 ppm of Mn and containing 6 ppm of Fe) is treated with this adsorber by changing the treatment amount per unit time. Moreover, the breakthrough characteristics of Fe and Mn are shown in FIG.

  In any case, no leak in the apparatus was observed, and good breakthrough characteristics were exhibited over a wide range of processing speed, and a removal rate of 95% or more was exhibited even in the presence of Mn and Fe.

In each figure (graph), the vertical axis represents C / C ₀ ; treated water concentration / raw water concentration, and the horizontal axis represents treated water volume / packed bed (filter) volume. SV is the space velocity and indicates processing speed (processing volume / time) / packed bed (filter) volume.

As described above, the adsorption apparatus of the present invention can be used for collecting, adsorbing and recovering various metal components (mainly Mn, Fe, etc.) in groundwater and well water, and metal components in industrial wastewater (plating wastewater). . The type and configuration of the chelate functional group are appropriately selected depending on the type of the target metal.
In the above description, the metal-capturing adsorption device and the recovery device mainly having a chelate functional group have been described. However, the device of the present invention can also be applied to a device using an ion-exchange functional nonwoven fabric filter.

The front sectional view shown typically of one embodiment of an adsorption tower. FIG. The typical perspective view of a spacer. The typical perspective view of the other example of the net-like body used for a spacer. The perspective view of the other example of a spacer. The typical flowchart of the collection | recovery apparatus of this invention. The graph which shows the comparison of the breakthrough curve of Fe when SV changes. The graph which shows the comparison of the breakthrough curve of Mn when SV changes. The graph which shows the breakthrough curve of each metal in the presence of Fe and Mn.

Explanation of symbols

10 Column container (adsorption tower body)
11, 12 Flange 13, 14 Support base 20 Filling layer 30 Spacer 31, 32 Line 33 Rim 40 Nonwoven fabric filter (chelate functionality)
H Transmission hole S Support part L Line part

Claims (7)

A packed bed is formed by laminating a nonwoven fabric filter having a metal-capturing functional group on the surface through a spacer in which a net-like permeation hole is formed in a column container. In the apparatus for adsorbing and removing metal components by allowing the raw water containing the metal components to pass through, the nonwoven fabric filter is made larger than the spacer, and the inner wall of the column container is sealed at the end of the filter. An apparatus for adsorbing metal components in water characterized by the above. The apparatus for adsorbing a metal component in water according to claim 1, wherein the spacer is formed by overlapping and joining parallel stripes to form a net-like permeation hole. The adsorption of the underwater metal component according to claim 1, wherein the spacer has a mesh-shaped transmission hole formed by a support portion of the filter and a wire portion connecting the support portion, and the thickness of the wire is smaller than the thickness of the support portion. apparatus. The apparatus for adsorbing a metal component in water according to any one of claims 1 to 3, wherein the spacer is a plastic molded product. The apparatus for adsorbing a metal component in water according to any one of claims 1 to 4, wherein the nonwoven fabric filter is composed of a composite fiber formed of a sheath portion having good reactivity and a core portion having strength. 5. The underwater metal component according to claim 1, wherein the nonwoven fabric filter is formed by forming a chelate functional group by graft polymerization on a nonwoven fabric composed of a composite fiber having a sheath part of PE and a core part of PP. Adsorption device. A suction device according to any one of claims 1 to 6 and a collecting washing liquid tank, so as to recover the adsorbed metal component was passed through the recovered cleaning solution of the recovered washing liquid tank to the adsorber An apparatus for recovering underwater metal components.

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