JPH10165733A - Filter media - Google Patents

Abstract

PROBLEM TO BE SOLVED: To exhibit denitrification performance and at the same time remove ammonium ion and phosphate ion by producing a filter material by molding synthetic resin such as poly(vinyl alcohol)-starch reacted product, lactic acid polymer, hydroxybutyric acid-hydroxyvaleric acid copolymer. SOLUTION: In a filter material to be used for a circulating and filtering apparatus for aquariums for aquarium fish and water tanks for cultivation of live fish, a filter material is produced by molding a synthetic resin selected from one or more of a poly(vinyl alcohol)-starch alloy, a lactic acid polymer, hydroxybutyric acid-hydroxyvaleric acid copolymer, a polyol-aliphatic dicarboxylic acid condensation-polymer, etc. Alternatively, a filter material is produced by molding a mixture of the above mentioned synthetic resin and one or more powders of zeolites and activated alumina. In the case the filter material is produced from a biodegradable synthetic resin in this way, nutrient source for denitrifying bacteria can be simultaneously supplied and total nitrogen and phosphate ion in water can be efficiently suppressed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a filter medium used for a circulating filtration device such as an aquarium for aquarium fish and an aquarium for storing live fish.

[0002]

2. Description of the Related Art Conventionally, these filter media are disclosed in
As described in -200788, a fixed amount of calcium silicate or magnesium compound, activated carbon, alumina-silica clay mineral, inorganic porous material such as vitreous, and granules thereof are charged into a water tank. is there.

[0003]

In the above-mentioned conventional filter media, in order to obtain a denitrification effect of converting a nitrogen compound in water into nitrogen gas and removing it from water, a denitrification effect of Pseudomonas or Bacillus is required. It has been necessary to separately add methanol or the like (hereinafter, referred to as a nutrient source of the denitrifying bacteria) serving as a hydrogen donor of a microorganism having the following (hereinafter, referred to as a denitrifying bacterium) to water.

Further, the filter medium itself has no function of removing ammonium ions and phosphate ions which cause water pollution.

[0005] The present invention solves these conventional problems and provides a denitrifying effect without the need to add a nutrient source of denitrifying bacteria, and at the same time, a filter medium having excellent ammonium ion and phosphate ion removal performance. The purpose is to provide.

[0006]

In order to achieve the above object, a first means of the present invention is to provide an alloy of polyvinyl alcohol and starch, a lactic acid polymer, a copolymer of hydroxybutyric acid and hydroxyvaleric acid, a polyol, At least one selected from the group consisting of polycondensation products of fatty acids and aliphatic dicarboxylic acids, poly (γ-methyl-L-glutamate) and poly (ε-caprolactone)
More than one kind of synthetic resin is molded to constitute a filter medium.

The second means of the present invention is an alloy of polyvinyl alcohol and starch, a lactic acid polymer, a copolymer of hydroxybutyric acid and hydroxyvaleric acid, a condensation polymer of polyols and aliphatic dicarboxylic acid, Poly (γ-methyl-
L-glutamate), poly (ε-caprolactone) and at least one synthetic resin to which at least one powder selected from zeolite and activated alumina is added to form a synthetic resin to form a filter material. .

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described in the following order with the above-described respective configurations.

[0009] The alloy of polyvinyl alcohol and starch constituting each means of the present invention comprises polyvinyl alcohol having a structure represented by the general formula (Chemical Formula 1), which is degradable by microorganisms (hereinafter referred to as biodegradable).

[0010]

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[0011] Similarly, it is an alloy with starch having biodegradability. When the alloy is formed into an alloy, the biodegradability is further increased, and it is a good nutrient source for denitrifying bacteria.

[0012] Further, by forming an alloy, good fluidity is produced, and the melt forming process is facilitated, and the shape of the filter medium can be freely selected, which is preferable.

Polyvinyl alcohol itself has biodegradability itself, but is water-soluble and has a high surface activity, so that use of the polyvinyl alcohol alone is not preferred for use in the present invention.

The lactic acid polymer constituting each means of the present invention comprises:
A synthetic resin synthesized through a cyclization reaction and ring-opening polymerization of lactic acid having a structure represented by the general formula (Formula 2),

[0015]

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It is highly biodegradable and is a good nutrient source for denitrifying bacteria. Further, the melt molding process is easy, and the shape of the filter medium can be freely selected, which is preferable.

The copolymer of hydroxybutyric acid and hydroxyvaleric acid constituting each means of the present invention comprises hydroxybutyric acid having a structure represented by the general formula (Formula 3):

[0018]

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A copolymer with hydroxyvaleric acid having a structure represented by the general formula (4):

[0020]

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It has high biodegradability and is a good nutrient source for denitrifying bacteria. Further, the melt molding process is easy, and the shape of the filter medium can be freely selected, which is preferable.

The condensation polymer of a polyol and an aliphatic dicarboxylic acid constituting each means of the present invention is obtained by condensation of a polyol such as 1.4-butadiol with an aliphatic dicarboxylic acid such as succinic acid or adipic acid. It is an aliphatic polyester obtained by polymerization, has high biodegradability, and is a good nutrient source for denitrifying bacteria.

Further, the melt molding process is easy, and the shape of the filter medium can be freely selected, which is preferable. The poly (γ-methyl-L-glutamate) constituting each means of the present invention has a structure represented by the general formula (Formula 5), has high biodegradability, and is a good nutrient source for denitrifying bacteria.

[0024]

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Further, the melt molding process is easy, and the shape of the filter medium can be freely selected, which is preferable. The poly (ε-caprolactone) constituting each means of the present invention has the general formula (Chem. 6)
It is highly biodegradable and is a good source of nutrients for denitrifying bacteria.

[0026]

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Further, the melt molding process is easy, and the shape of the filter medium can be freely selected, which is preferable. Next, the zeolite constituting the second means of the present invention is a crystalline aluminosilicate having a three-dimensional skeleton structure, and either a natural zeolite or a synthetic zeolite can be used. Representative examples of zeolites include A-type zeolite, X-type zeolite, Y-type zeolite, P-type zeolite, high silica zeolite, sodalite, mordenite, analcyme, clinobutyrolite, chabazite, erionite. And the like.

These zeolites can particularly effectively remove ammonium ions in water by ion exchange.

The activated alumina constituting the second means of the present invention is mainly composed of γ-alumina obtained by dehydrating aluminum oxide at a temperature of 700 ° C. or less, and containing saturated γ-alumina. It can adsorb almost any compound except hydrogen, and can effectively adsorb and remove particularly phosphate ions in water.

By forming the filter medium with these highly biodegradable synthetic resins, it is possible not only to provide a place for denitrifying bacteria, which is the basic function of the filter medium, but also to supply a nutrient source of the denitrifying bacteria at the same time. Become.

Further, by adding zeolite to these highly biodegradable resins to form a filter medium, ammonium ions in water are adsorbed and removed, and act synergistically with the removal of nitrogen by denitrification to produce total nitrogen in water. Can be reduced.

Further, by adding activated alumina to these highly biodegradable resins to constitute a filter material, phosphate ions in water can be effectively reduced.

When zeolite or activated alumina is added to these highly biodegradable synthetic resins to form a filter material, the synthetic resin decomposed by the denitrifying bacterium becomes a lower molecular weight organic substance (monomer, etc.) and is dropped from the filter material surface. Since it is removed, the surface of fresh zeolite and activated alumina is always exposed in water, and the efficiency of removing ammonium ions and phosphate ions is further improved.

[0034]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Specific examples of the present invention will be described below.

The present invention is not limited to these specific examples. (Example 1) As a typical example of an alloy of polyvinyl alcohol and starch, trade name Materby AI05H (manufactured by Nippon Synthetic Chemical Industry Co., Ltd.) was used.
A cylindrical filter medium having a length of 10 mm was obtained by an injection melt molding method (melting temperature: about 165 ° C).

60 g of the present filter medium is put into 100 L of water previously adjusted to a concentration of 10 ppm as ammonia nitrogen using ammonium chloride, and water is circulated with an 8 L / min pump to circulate ammonia nitrogen, nitrite nitrogen, and nitrate. The time change of the nitrogen concentration was measured.

The results are shown in Table 1 as a comparative example together with a filter medium comprising calcium silicate and a magnesium compound (corresponding to a conventional filter medium).

[0038]

[Table 1]

As is apparent from Table 1, the present embodiment 1
Since the filter medium has a more effective denitrifying effect and releases nitrite ions as nitrogen gas as compared with Comparative Example 1, the concentration of nitrite nitrogen is extremely low. It can be seen that the concentration of nitrogen is also small.

Example 2 As a typical example of a lactic acid polymer,
Using the product name Rakuti (Shimadzu Corporation), outer diameter 1
A cylindrical filter medium having a diameter of 0 mm, an inner diameter of 4 mm and a length of 10 mm was obtained by an injection melt molding method (melting temperature: about 160 ° C.).

60 g of the present filter medium is put into 100 L of water previously adjusted to a concentration of 10 ppm as ammonia nitrogen using ammonium chloride, and water is circulated by an 8 L / min pump to circulate ammonia nitrogen, nitrite nitrogen and nitrate. The time change of the nitrogen concentration was measured.

The results are shown in Table 2 together with a filter material comprising calcium silicate and a magnesium compound (corresponding to a conventional filter material) as a comparative example.

[0043]

[Table 2]

As is evident from (Table 2), the present embodiment 2
The filter medium has a denitrifying effect more effective than that of Comparative Example 2 and releases nitrite ions as nitrogen gas. Therefore, the concentration of nitrite nitrogen is remarkably low. It can be seen that the concentration of nitrogen is also small.

(Example 3) As a typical example of a copolymer of hydroxybutyric acid and hydroxyvaleric acid, Biopol D311G (trade name, manufactured by Monsanto Japan Limited) was used and had an outer diameter of 10 mm, an inner diameter of 4 mm, and a length of 10 mm. A cylindrical filter medium was obtained by an injection melt molding method (melting temperature about 170 ° C).

60 g of the present filter medium is put into 100 L of water previously adjusted to a concentration of 10 ppm as ammonia nitrogen using ammonium chloride, and water is circulated by a pump of 8 L / min to circulate ammonia nitrogen, nitrite nitrogen and nitrate. The time change of the nitrogen concentration was measured.

The results are shown in Table 3 as a comparative example together with a filter medium comprising calcium silicate and a magnesium compound (corresponding to a conventional filter medium).

[0048]

[Table 3]

As is clear from Table 3, the present embodiment 3
The filter medium has a denitrification effect more effective than Comparative Example 3, and releases nitrite ions as nitrogen gas. Therefore, the concentration of nitrite nitrogen is extremely low. It can be seen that the concentration of nitrogen is also small.

(Example 4) As a typical example of a condensation polymer of a polyol and an aliphatic dicarboxylic acid, trade name Bionore # 1020 (manufactured by Showa Polymer Co., Ltd.) was used.
A cylindrical filter medium having a diameter of 0 mm, an inner diameter of 4 mm and a length of 10 mm was obtained by an injection melt molding method (melting temperature: about 170 ° C.).

60 g of the present filter medium is put into 100 L of water previously adjusted to a concentration of 10 ppm as ammonia nitrogen using ammonium chloride, and water is circulated by an 8 L / min pump to circulate ammonia nitrogen, nitrite nitrogen and nitrate. The time change of the nitrogen concentration was measured.

The results are shown in Table 4 together with a filter medium comprising calcium silicate and a magnesium compound (corresponding to a conventional filter medium) as a comparative example.

[0053]

[Table 4]

As is clear from (Table 4), the present embodiment 4
Since the filter medium has a more effective denitrifying effect and releases nitrite ions as nitrogen gas as compared with Comparative Example 4, the concentration of nitrite nitrogen is remarkably low. It can be seen that the concentration of nitrogen is also small.

(Example 5) As a typical example of poly (γ-methyl-L-glutamate), trade name Ajiquat A-200 is used.
0 (manufactured by Ajinomoto Co., Inc.), outer diameter 10 mm, inner diameter 4 m
A cylindrical filter medium having a length of 10 mm and a length of 10 mm was obtained by an injection melt molding method (melting temperature: about 155 ° C.).

60 g of the present filter medium is put into 100 L of water previously adjusted to a concentration of 10 ppm as ammonia nitrogen using ammonium chloride, and water is circulated by a pump of 8 L / min to circulate ammonia nitrogen, nitrite nitrogen, nitrate. The time change of the nitrogen concentration was measured.

The results are shown in Table 5 as a comparative example together with a filter medium comprising calcium silicate and a magnesium compound (corresponding to a conventional filter medium).

[0058]

[Table 5]

As apparent from (Table 5), this embodiment 5
In the filter medium of the present invention, the denitrification effect works more effectively and the nitrite ions are released as nitrogen gas as compared with Comparative Example 5, so that the concentration of nitrite nitrogen is remarkably low. It can be seen that the concentration of nitrogen is also small.

Example 6 Poly (ε-caprolactone)
As a typical example, a trade name of Placcel H-4 (manufactured by Daicel Chemical Co., Ltd.) is used.
mm cylindrical filter media were obtained by injection melt molding (melting temperature about 155 ° C).

60 g of the present filter medium is put into 100 L of water previously adjusted to a concentration of 10 ppm as ammonia nitrogen using ammonium chloride, and water is circulated by an 8 L / min pump to circulate ammonia nitrogen, nitrite nitrogen and nitrate. The time change of the nitrogen concentration was measured.

The results are shown in Table 6 together with a filter material comprising calcium silicate and a magnesium compound (corresponding to a conventional filter material) as a comparative example.

[0063]

[Table 6]

As is clear from Table 6, this embodiment 6
In the filter medium of the present invention, since the denitrification function works more effectively and the nitrite ions are released as nitrogen gas as compared with Comparative Example 6, the concentration of nitrite nitrogen is extremely low. It can be seen that the concentration of nitrogen is also small.

Example 7 As a typical example of a lactic acid polymer,
Pellets 50% by weight of trade name Lacty (manufactured by Shimadzu Corporation) and 50% by weight of trade name Biopol D311G (manufactured by Nippon Monsanto Co., Ltd.) as a representative example of a copolymer of hydroxybutyric acid and hydroxyvaleric acid The mixture was mixed in a state, and a single mixture (pellet) was obtained using a 40 mm single screw extruder.

Using this single mixture, outer diameter 10 mm, inner diameter 4 m
A cylindrical filter medium having a length of 10 mm and a length of 10 mm was obtained by an injection melt molding method (melting temperature: about 165 ° C.).

60 g of the present filter medium is placed in 100 L of water previously adjusted to a concentration of 10 ppm as ammonium nitrogen using ammonium chloride, and water is circulated by an 8 L / min pump to circulate ammonia nitrogen, nitrite nitrogen, and nitrate. The time change of the nitrogen concentration was measured.

The results are shown in Table 7 together with a filter material comprising calcium silicate and a magnesium compound (corresponding to a conventional filter material) as a comparative example.

[0069]

[Table 7]

As is clear from (Table 7), this embodiment 7
In the filter medium of the present invention, the denitrification effect works more effectively and the nitrite ions are released as nitrogen gas as compared with Comparative Example 7, so that the concentration of nitrite nitrogen is extremely low. It can be seen that the concentration of nitrogen is also small.

Example 8 As a representative of a copolymer of hydroxybutyric acid and hydroxyvaleric acid, a natural zeolite having an average particle size of about 3 μm and a uniaxial extrusion of 40 mm were applied to Biopol D311G (trade name, manufactured by Monsanto Japan Limited). 16% by weight was added using a mixer.

An outer diameter of 10 mm and an inner diameter of 4
A cylindrical filter medium having a length of 10 mm and a length of 10 mm was obtained by an injection melt molding method (melting temperature: about 170 ° C.).

60 g of the present filter medium is put into 100 L of water previously adjusted to a concentration of 10 ppm as ammonia nitrogen using ammonium chloride, and water is circulated by an 8 L / min pump to circulate ammonia nitrogen, nitrite nitrogen and nitrate. The time change of the nitrogen concentration was measured.

The results are shown in Table 8 together with a filter material comprising calcium silicate and a magnesium compound (corresponding to a conventional filter material) as a comparative example.

[0075]

[Table 8]

As is clear from Table 8, this embodiment 8
The filter medium has a denitrification effect more effective than Comparative Example 8, releases nitrite ions as nitrogen gas, and the zeolite added to the filter medium effectively removes ammonium ions from water. It can be seen that the concentration of nitrate nitrogen is extremely low, and as a result, the concentration of nitrate nitrogen generated by oxidation of nitrite ions is also low.

Example 9 As a typical example of a copolymer of hydroxybutyric acid and hydroxyvaleric acid, a natural zeolite having an average particle size of about 3 μm and an average particle size of Biopol D311G (manufactured by Monsanto Japan Limited) were used. 1 μm of activated alumina was added in an amount of 16% by weight using a 40 mm single screw extruder.

An outer diameter of 10 mm and an inner diameter of 4
A cylindrical filter medium having a length of 10 mm and a length of 10 mm was obtained by an injection melt molding method (melting temperature: about 170 ° C.).

[0079] 60 g of the present filter medium was converted into ammonia nitrogen using ammonium chloride and sodium dihydrogen phosphate.
ppm, phosphoric acid phosphorus, put in 100 L of water adjusted to a concentration of 12 ppm in advance, circulate water with a pump of 8 L / min, and simulate ammonia ammonia, nitrite nitrogen, nitrate nitrogen, phosphate phosphorus concentration time The change was measured.

The results are shown in Table 9 as a comparative example together with a filter medium comprising calcium silicate and a magnesium compound (corresponding to a conventional filter medium).

[0081]

[Table 9]

As apparent from (Table 9), the present embodiment 9
The filter medium of the present invention has a denitrifying effect more effective than that of Comparative Example 9 to release nitrite ions as nitrogen gas, and the zeolite added to the filter medium effectively removes ammonium ions from water. It can be seen that the concentration of body nitrogen is extremely low, and as a result, the concentration of nitrate nitrogen generated by oxidation of nitrite ions is also small.

Further, since the activated alumina added to the filter medium effectively removes phosphorus ions from water, it can be seen that the concentration of phosphoric acid phosphorus is significantly lower than that of Comparative Example 9.

Although the shape of the filter medium used in Examples 1 to 9 is cylindrical, the shape of the filter medium is not limited to this.

The amount of zeolite used in Examples 8 and 9 was 16% by weight. However, the amount of zeolite added is not limited to this, and the required ammonia reduction effect and various conditions for the amount of water are required. Can be changed arbitrarily.

The amount of activated alumina used in Example 9 was set at 16% by weight, but the amount of activated alumina added is not limited to this. It can be arbitrarily changed according to conditions.

[0087]

As described above, according to each means of the present invention,
Alloy of polyvinyl alcohol and starch, lactic acid polymer,
Synthetic resin of at least one of a copolymer of hydroxybutyric acid and hydroxyvaleric acid, a condensation polymer of polyols and aliphatic dicarboxylic acid, poly (γ-methyl-L-glutamate) and poly (ε-caprolactone) An alloy of polyvinyl alcohol and starch, a lactic acid polymer, a copolymer of hydroxybutyric acid and hydroxyvaleric acid, a condensation polymer of polyols and an aliphatic dicarboxylic acid, (Γ-methyl-L
Glutamate), poly (ε-caprolactone), and at least one synthetic resin added with at least one powder selected from zeolite and activated alumina to form a synthetic resin to form a filter material. Denitrification can be obtained without the need to add nutrients for nitrifying bacteria,
Further, it has an effect of being excellent in the performance of removing ammonium ions and phosphate ions at the same time.

──────────────────────────────────────────────────続 き Continued on front page (51) Int.Cl. ⁶ Identification code FI C02F 3/10 C02F 3/10 A

Claims (2)

[Claims] An alloy of polyvinyl alcohol and starch,
Lactic acid polymer, copolymer of hydroxybutyric acid and hydroxyvaleric acid, condensation polymer of polyols and aliphatic dicarboxylic acid, poly (γ-methyl-L-glutamate), poly (ε
-Caprolactone) of at least one synthetic resin. 2. An alloy of polyvinyl alcohol and starch,
Lactic acid polymer, copolymer of hydroxybutyric acid and hydroxyvaleric acid, condensation polymer of polyols and aliphatic dicarboxylic acid, poly (γ-methyl-L-glutamate), poly (ε
-Caprolactone) formed from a synthetic resin obtained by adding at least one kind of powder selected from zeolite and activated alumina to at least one kind of synthetic resin.