JP2006096570A - Fertilizer, soil conditioner, and method for reclaiming photographic wastewater - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for reclaiming photographic wastewater into a fertilizer or a soil conditioner not causing plant growth inhibition and to thereby reduce load on environmental protection, cost, and workability in photographic wastewater treatment, which method can be practiced even in photographic minilaboratories. <P>SOLUTION: The fertilizer is obtained by removing tar or a tar precursor from photographic wastewater and optionally adjusting component concentrations. Desirably, the fertilizer is devoid of silver and halides, or is obtained from photographic wastewater subjected to electrolytic oxidation or chemical oxidation. The soil conditioner utilizing the fertilizer is also provided. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to the processing of photographic waste liquid, and specifically relates to the reduction of the environmental burden associated with the processing of photographic waste liquid, and more specifically to the reuse of photographic waste liquid for fertilizers and soil conditioners.

  The photographic waste liquid contains high-concentration BOD, COD, and nitrogen components, and contains components that are not easily decomposed by biological treatment or chemical treatment. Accordingly, the photographic waste liquid, particularly the color development processing waste liquid, is one of the waste liquids that are difficult to process to enable direct discharge to the environment, and many processing methods have been disclosed. For example, biological treatment methods represented by the activated sludge method, chemical oxidation methods such as ozone, hydrogen peroxide-ferrous salt, persulfuric acid and halogen acids, electrolytic oxidation methods, and physical treatment methods such as high-pressure heating and spray incineration Etc. However, the method of detoxifying and discharging the waste liquid by this method is problematic in that it is costly for waste liquid treatment and wastes resources.

  For this reason, large developing laboratories (called large labs) reconstitute components that have been used and recycle them, or reduce their replenishment by reducing the amount of photographic waste, but that alone solves the problem. Not enough. Because of the small-scale processing, in-store development laboratories (referred to as minilabs) in which such regeneration processing and low replenishment processing are difficult, rational waste liquid countermeasures are more strongly demanded.

As a practical countermeasure for minilab waste liquid treatment, waste liquid is collected by a waste liquid collector and incinerated. Incineration without exhausting hazardous substances into the atmosphere and water environment requires incineration using a large-scale incinerator equipped with a flue gas treatment facility, which places a high processing cost. In addition, in order to avoid clogging of piping due to high melting point inorganic salts such as iron oxide generated during combustion and exhaustion of the combustion furnace, it is necessary to install a chemical deironing process, which makes the process and operation more complicated. The following problems are also included.
Under such circumstances, in the processing of photographic waste liquid, there is a demand for an appropriate method that can be processed without impacting the environment as much as possible and that does not have a large processing cost load. In addition, since photographic waste liquid contains useful high-concentration chemical components, reuse from waste liquid detoxification is also desired from the viewpoint of resource saving.

In terms of the reuse of resources, Patent Document 1 discloses a method for producing organic compost having a high fertilizer component by adjusting the pH of organic waste and treating the microorganism, and Patent Document 2 discloses wood vinegar. A method is disclosed in which waste liquid is treated with microorganisms to form fertilizer. However, these are reuse of waste mainly composed of natural organic matter. Unlike those derived from these natural organic substances, photographic waste liquids with a high salt concentration, high ionic strength, and mainly synthetic chemicals have not been tried to fertilize by other methods, not only microbial treatment methods.
On the other hand, Patent Document 3 discloses a method of reusing a plating waste liquid as a fertilizer by electrolytic oxidation treatment. Since this plating waste liquid contains a large amount of phosphate and soot phosphate, the electrolytically oxidized liquid is valuable as a phosphate fertilizer. The photographic waste liquid does not have the incentive like the plating waste liquid in that the phosphorus compound is removed from the treatment liquid prescription due to the regulation by the environmental laws and regulations.

The above-mentioned prior art relating to the invention of this application includes the following documents.
JP 2002-153846 A JP-A-6-65019 Japanese Patent Laid-Open No. 9-40482

As described above, in any of large labs as well as mini-labs, none of the photographic waste liquid processing methods disclosed in the prior art is insufficient in terms of removal rate, processing cost, ease of work, and chemical resources. There is a demand for an appropriate response means that can solve the problem that has led to waste.
The present inventor tried to recycle the photographic waste liquid as a fertilizer as a means of solving this problem by paying attention to the fact that the photographic waste liquid contains a fertilizer component necessary for plant growth. It was found that the plant growth inhibition was caused and the fertilization effect was not fully exhibited, and as a result of pursuing the cause, it was found that the tar content in the photographic waste liquid adsorbed around the plant roots.
Therefore, a specific object of the present invention is to provide a fertilizer that can be implemented in a minilab and reuses a photographic waste liquid that is not accompanied by plant growth inhibition, thereby protecting the environment related to waste liquid treatment, It is to reduce the burden of cost and workability.

  The present inventor has been able to arrive at the present invention described below through intensive studies in order to find a solution for the above object.

(1) A fertilizer obtained by removing tar or a tar precursor from a photographic waste liquid and adjusting the component concentration as necessary.
(2) The fertilizer according to (1) above, wherein the fertilizer is obtained by removing tar or a tar precursor from a photographic waste solution by adsorbing the tar or a tar precursor to the oil adsorbent.
(3) The fertilizer according to (1) above, wherein the fertilizer is obtained by removing tar or a tar precursor from a photographic waste liquid by adsorbing the tar or a tar precursor to the oil adsorption film.
(4) The fertilizer according to any one of (1) to (3), which is obtained by subjecting a photographic waste solution to electrolytic oxidation treatment and removing tar during or after the oxidation treatment.
(5) The fertilizer according to any one of (1) to (3) above, which is obtained by subjecting a photographic waste solution to chemical oxidation treatment and removing tar during or after the oxidation treatment.
(6) The above-mentioned (1) to (3), which are obtained without subjecting the photographic waste solution from which the tar precursor has been removed to electrolytic oxidation treatment or chemical oxidation treatment, but adjusting the component concentration as necessary. ) Fertilizer according to any one of
(7) The fertilizer according to any one of the above (1) to (6), wherein the silver contained in the photographic waste liquid is recovered in addition to the removal of the tar or the tar precursor.
(8) The fertilizer according to any one of (1) to (7) above, wherein a treatment for reducing the concentration of halide in the photographic waste liquid is performed in addition to the removal of the tar or the tar precursor.
(9) The fertilizer according to (8) above, wherein the treatment for reducing the concentration of halide is an electrodialysis treatment using an ion exchange membrane or an ion exchange resin treatment.

(10) A soil improver comprising the base material containing the fertilizer according to any one of (1) to (9) above.
(11) The base material is perlite, permiculite, akadama soil, kanuma soil, compost, humus, peat moss, water-absorbing polymer, synthetic and / or natural zeolite, synthetic and / or natural clay, gelatin, wood chips and ground wood chips. The soil improver according to (10) above, which is at least one selected from the group consisting of:
(12) Reuse of photographic waste liquid, wherein the fertilizer according to any one of (1) to (9) above or the soil conditioner according to (10) or (11) above is obtained using the photographic waste liquid. Method.

  The fertilizer of the present invention obtained by removing tar or a tar precursor from a photographic waste liquid and adjusting the component concentration as necessary is a fertilizer containing nitrogen and potassium components, and further containing trace plant nutrients such as iron. There is a fertilizer with three elements by supplementing the phosphorus component. This fertilization can be performed by a simple operation that can be carried out in a minilab, whereby the photographic waste liquid can be effectively reused. Furthermore, when this fertilizer is mix | blended with a substrate with another additive component, a soil modifier is obtained and a photographic waste liquid can be reused similarly. As a result, it is possible to reduce the amount of photographic waste liquid that has a large environmental impact.

Hereinafter, the present invention will be described in more detail.
In this specification, “photographic processing waste liquid” and its simplified expression “photographic waste liquid” are synonymous. In addition, “removal of halide”, “removal of silver”, and “desilvering” are used to mean “reduction of halide concentration” and “reduction of silver concentration”, respectively. It does not mean removing silver.

The photographic waste liquid is an aqueous solution of high salt concentration, high ionic strength and mainly synthetic chemical substances (nitrogen compounds are also mainly synthetic chemical substances), even though it contains fertilizers such as potassium and ammonium components. Some contain color developing agents that are harmful to microorganisms, so there are too many restrictions to apply to fertilizers and soil modification. Surprisingly, however, it has been found that removal of tars and / or tar precursors in photographic waste liquids eliminates the plant growth inhibitory effect and exerts a fertilizing effect even in waste liquids having such properties. It was.
The removal of the tar and / or tar precursor may be performed directly on the photographic waste liquid, may be performed after the electrolytic oxidation treatment is performed on the photographic waste liquid, or may be performed after the chemical oxidation treatment is performed. . Electrolytic oxidation treatment or chemical oxidation treatment increases the amount of tar in the photographic waste liquid, but increases the fertilization effect of the waste liquid from which the tar has been removed.
Tar is a tar-like insoluble precipitate formed in a photographic processing solution during processing of a photosensitive material using a photographic processing solution or during storage of the processing solution in contact with air. This refers to dissolved components in photographic processing solutions that cause tar. Tar precursors are mainly color developing agents.

Although photographic waste liquids are inherently high in salt concentration and high ionic strength, surprisingly, waste liquids from which tar or precursors have been removed have the favorable result that the adverse effects are not significant. Furthermore, the nitrogen-containing compound (non-ammonium chemical synthesis product) in the waste liquid further brings about the nitrogen component of the fertilizer due to electrolytic oxidation or chemical oxidation (this is thought to be because the nitrogen-containing compound becomes nitrate or oxalate nitrogen) ) Therefore, the effect as a fertilizer or a soil modifier component appears in paddy fields, upland fields, swamps, and wetlands. In addition, the photographic waste liquid has a fertilizing effect that is characterized by a high amount of iron compounds. Furthermore, removing (reducing) the halides normally present in the photographic waste liquid reduces the risk of soil degradation such as soil solidification, high chlorination or reduced water retention, which is more convenient for maintaining geopower, The effect of soil modifier is obtained. In the present invention, it is desirable to reduce halide in the photographic waste liquid by using an ion exchange membrane, an ion exchange resin, or the like.
Further, preferably, silver resources can be reused by recovering silver in the waste liquid from the photographic waste liquid (before or after electrolytic oxidation or chemical oxidation, or during oxidation treatment).

Further, by adding a fertilizer component, that is, a phosphorus compound, that is lacking in the photographic waste liquid that has been subjected to tar and / or tar precursor removal treatment, it is possible to provide a fertilizer with wide applicability by including all three elements of fertilizer. In addition, the quality of the fertilizer can be improved by adding micronutrients necessary for plants and not present in photographic waste.
Also, fertilization effect by mixing and adjusting the fertilizer with added phosphorus component and preferably other components useful for plant growth to the photographic waste liquor from which the halide has been removed, preferably further desilvered, It can be set as the soil modifier excellent in water retention and air permeability.

[Photo waste liquid]
Prior to the description of the embodiment of the present invention, the photographic processing waste liquid that is the subject of the invention will be described. The photographic processing waste liquid includes many kinds of waste liquid generated in the photographic industry such as fixing waste liquid or photolithography, in addition to developing waste liquid for color photography or monochrome photography. As the fixing waste liquid, the residual liquid from which the dissolved silver is recovered becomes the target of processing. Usually, waste liquids from these various photographic processing steps are collected and processed in a mixed state. In the present invention, it is preferable from the component constitution to use a waste liquid for color photography for that purpose.
The development waste liquid constituting the photographic waste liquid is the waste liquid discharged from each step of the development processing, and components such as gelatin and photosensitive dye eluted from the photosensitive material during the processing, reaction products generated during the processing, and It is a waste liquid that contains constituent chemicals that have not been consumed by being included in the treatment liquid formulation (details of the treatment liquid formulation will be described later).

Color developer waste mainly contains developing agents and their oxidation products, alkali compounds and buffers, preservatives selected from sulfites and hydroxylamine derivatives, alkali halides, etc. Mainly ammonium salt, sodium salt and / or sulfite ammonium salt and / or sodium salt, alkali halide, etc., bleaching waste liquid is bleaching agent such as iron (III) complex salt of polyaminopolycarboxylic acid and reaction product derived from it , Alkali halides (rehalogenating agents), buffer salts, etc. The bleach-fixing waste liquid is mainly composed of the same components as those contained in the fixing waste liquid and the bleaching waste liquid, and is discharged from other processes. The waste liquid also contains the functional compounds of those process liquids and the compounds derived therefrom. Therefore, the components of the photographic waste liquid to be processed include components derived from a developer, components derived from a bleaching solution, a fixing solution, and a bleach-fixing solution, which are mixed with a photosensitive material eluate and a reaction product during processing. Agents (carbonates, phosphates, borates, tetraborate, hydroxybenzoates, etc.), color developing agents, sulfites, hydroxylamine salts, carbonates, water softeners, alkylene glycols, benzyl alcohols , Surfactant (alkylphosphonic acid, arylphosphonic acid, fatty acid carboxylic acid, aromatic carboxylic acid, etc.), oxidizing agent (iron (III) EDTA complex salt, 1,3-diamino-propanetetraacetic acid complex salt, etc.), halide ( It contains a wide variety of chemical components such as alkali bromide and ammonium bromide), thiosulfate (sodium salt, ammonium salt), and acetate. Further details of the components derived from the processing liquid of the photographic waste liquid will be described in the section of photographic processing described later.
Various photosensitive material additive components and their reaction products are also eluted from the photosensitive material into the processing solution during the processing. Silver halide elutes into the processing solution as silver complex salts and halide ions, and is accompanied by the photosensitive dye (color sensitizer), fog prevention, chemical sensitization, and other purposes. The nitrogen-containing heterocyclic compound, the compound released from the coupler or DIR compound (in many cases, a nitrogen compound) is eluted in the treatment liquid. Further, the surfactant and the like are eluted from the binder of the photosensitive layer. Further details of the compound eluted from the light-sensitive material are described in the section of light-sensitive material described later.
Therefore, as described above, the photographic processing waste liquid contains fertilizer elements such as nitrogen compounds and potassium compounds derived from the processing liquid and the photosensitive material, but at the same time has a sulfur compound, an iron complex salt and a high salt concentration. This diversity makes it difficult to find effective waste liquid treatment means, and at the same time makes it difficult to find a recycling method, but the present invention leads to the solution.

  The composition of photographic wastewater from the viewpoint of water quality environment varies considerably depending on the type of treatment and the mixing ratio of wastewater from each step of the treatment, but it is approximately COD5,000-60,000 mg / L, BOD5,000-15,000 mg / L Ll, TOC (Total Organic Carbon) 5,000-25,000 mg / l, Kjeldahl nitrogen 5,000-15,000 mg / L. The ratio of COD: BOD: TOC is approximately 4: 1: 1.5, which is characterized by high COD, and the elemental ratio of C: N is approximately 100: 100, which is characterized by high N content. Moreover, the content of potash components derived from potassium carbonate, potassium hydroxide and the like is also large. The characteristics of this photographic waste liquid make it difficult to easily render the photographic waste liquid harmless in terms of water quality. On the other hand, when the composition of the photographic waste liquid is viewed from the viewpoint of fertilizer components, a high concentration of nitrogen compounds ( The above-mentioned) and potassium compounds (often 1000 to 10000 mg / L as K element), and the iron component desired for foliar fertilizers suitable for green leafy vegetables and lawns is also an aminopolycarboxylic acid iron (III) complex salt (In many cases, 500 to 5000 mg / L as Fe element). Accordingly, the photographic waste liquid is a waste liquid having such a property that it can be used as a fertilizer or a soil improver if the adverse effects on plants and soil associated with high halide concentration and high ionic strength can be solved.

[Preparation process of fertilizer from photographic waste liquid]
(Removal of tar or tar precursor)
Any method can be used to remove tar or tar precursor from the photographic waste liquid as long as it can be removed. However, as a preferable method, i) it is adsorbed on an oil adsorbent and then separated from the waste liquid. And ii) a method of removing the occlusion membrane from the waste liquid after occlusion in the oil adsorption membrane.
As the oil adsorbent, various inorganic and organic adsorbents can be used. For example, synthetic or natural zeolite, synthetic or natural clay, pearlite, permiculite, montmorillonite, activated carbon, and Kanuma soil can be used as the inorganic adsorbent. it can. As the organic adsorbent, peat moss, polypropylene, water-absorbing polymer, sawdust, groundwood chip, pulp, linter, cellulose esters such as carboxymethylcellulose, hydroxyethylcellulose, acetylcellulose, and various commercially available oil adsorbents can be used. For example, natural cellulose-based adsorbent (trade name Cellsorb, supplier Morgen Roth), natural plant-based adsorbent (trade name oil sponge, supplier Endo Kogyo Co., Ltd.) are commercially available, but are not limited thereto. . Add 0.1 to 100 g, preferably 1 to 50 g per liter of photographic waste liquid, and leave it for 1 day with occasional stirring. Adsorb tar and precursor after 1 hour or more, preferably 6 hours with continuous stirring with a stirrer. The floated oil adsorbent is separated only by the upper liquid or by filtration.
Commercially available products such as polypropylene and polystyrene film-formed molded products can be used as the oil adsorption film. For example, trade names Neo Attack Ace, Ryoka Etec, trade name nail pad, Hashimoto Cross, trade name rug mat And rag rolls and Ganesh Trading Co., but are not limited to these. Add 0.1 to 100 g, preferably 1 to 50 g, per liter of photographic waste liquid and leave it for 1 day with occasional stirring. After 1 hour or more, preferably 6 hours with continuous stirring, the tar and precursor are occluded. The tar and precursor are removed by removing the oil-adsorbed film from the waste liquid.
The used oil adsorbent and the oil adsorbing film are heat recovered by incineration.

(Electrolytic oxidation treatment)
The electrolytic oxidation treatment of photographic processing waste liquid by the method of the present invention will be described.
<Adjustment of waste liquid>
In the present invention, the photographic processing waste liquid may be subjected to electrolytic treatment without adjusting the pH or adding a supporting electrolyte. If necessary, the pH may be adjusted using an alkaline agent such as sodium hydroxide, potassium hydroxide, calcium hydroxide or sodium carbonate prior to the electrolytic oxidation treatment or during electrolysis. This is because, when the liquid to be treated is acidified during electrolysis, bromine ions, chlorine ions and iodine ions in the components are oxidized to generate respective halogen gases. Also, alkaline pH is preferable for COD decomposition efficiency. The alkaline agent to be added may be in any form of solid, aqueous solution, suspension, etc. The addition method may be added prior to the electrolytic oxidation treatment, and electrolysis is recommended in conjunction with an automatic adjustment device. May be. The pH may be adjusted to be maintained at 7 or higher, preferably pH 8 or higher during the electrolysis operation.
On the other hand, the pH is preferably 12.5 or less in order to suppress precipitation formation due to hydrolysis of the iron complex salt compound.

<Electrolytic oxidation>
The electrolytic oxidation method will be described. Since photographic waste liquid is highly corrosive, it is necessary to select platinum, ferrite, stainless steel, iron on which an oxide film is rapidly formed, hard plastic, etc., which are corrosion resistant materials that can withstand these components.

The anode is preferably a corrosion-resistant material that is difficult to oxidize, such as platinum, stainless steel, carbon (particularly graphite, glassy carbon, diamond formed on a substrate), titanium, iron on which an oxide film is rapidly formed, or the like.
Among them, a preferable anode is a so-called diamond electrode, that is, an electrode in which a carbon layer having a diamond structure is formed on a substrate, and has an advantage that oxidation proceeds efficiently because there is little competition with water anodic oxidation. In order to give good conductivity to the diamond structure layer, it is necessary to add a small amount of elements having different valences (doping). For example, phosphorus or boron is contained in an amount of 1 to 100,000 ppm, preferably about 100 to 10,000 ppm. . As a raw material compound of this additive, boron oxide, diphosphorus pentoxide, etc., which are less toxic are preferable. As a doping method, a hot filament CVD (HFCVD) method (see Klages, Appl. Phys. A56 (1993) pp. 513 to 526) or a vacuum chamber described in JP-A-8-225395, paragraph 0007 is used. Chemical vapor deposition methods are known. Details of the diamond electrode are described in Japanese Patent No. 3442888.

The cathode is not directly involved in the electrolytic oxidation reaction, but platinum, stainless steel, titanium, carbon, etc., which are materials inert to the waste liquid, are preferable.
For example, the anode is preferably a stainless steel electrode, a diamond electrode, or an iron electrode on which an oxide film is rapidly formed, and the cathode is preferably an electrode such as stainless steel or titanium.
In addition, since the reaction solution contains a large amount of suspended components, a rotating electrode is used to prevent precipitation of the suspended matter on the electrode to cause a uniform oxidation reaction and increase current efficiency. It is also preferable.

  In the present invention, the structure of the electrolytic cell can be used in various known configurations. That is, it may be a single chamber cell or a divided cell in which the anode and the cathode are partitioned by a film. The simplest embodiment is a single chamber cell. In a single chamber cell, there is no barrier separating the anode and cathode, so the solute is not restricted from moving between the anode and cathode. Such a single-chamber method generally has a possibility that the component oxidized at the anode is subsequently reduced at the cathode, but in the case of the electrooxidative decomposition reaction of the photographic waste liquid component, the oxidation species Most of them are subject to irreversible oxidation, so the risk is low.

  In the two-chamber cell, a conductive membrane such as an ion exchange membrane, a microfiltration membrane, a semipermeable membrane, and a porous membrane such as porous ceramics is inserted between the anode and the cathode. An ion exchange membrane can only pass certain types of ionic species from anolyte to catholyte or vice versa. The function of the membrane is to maintain electrical neutrality without mixing the anolyte and catholyte. In addition, if an appropriate film is used, the nature of ions moving through the film can be controlled. For example, a preferred embodiment of the present invention is possible in which silver sulfide is generated and precipitated for sulfur ions generated by reduction of thiosulfate ions or sulfite ions in the cathode chamber and collected in the cathode chamber. Of these, ion exchange membranes, semipermeable membranes, ceramics, and the like are preferable as the separation membrane.

The temperature of the electrolytic oxidation treatment is preferably normal temperature or slightly higher than this, the voltage is preferably 5.0 to 8.0 V, and the current density is preferably 0.5 to 100 A / dm ² , more preferably 5 to 50 A / dm. ² is good.
Electrolysis may be either a batch method or a continuous method. As a preferable voltage application method of the batch type, a relatively low current density of 4 to 6 A / dm ² is applied at the initial stage of electrolysis (between 2 to 10% of the COD reduction target value), and the current density is increased with the progress of electrolysis after electrolysis 10% considerable COD reduction target value by increasing are also preferred embodiments continue electrolysis by applying constant current density, for example, a current density of 12~20A / dm ^2.

For electrolytic oxidation in the present invention, any of a batch method, a recirculation method, and a continuous method may be used, and the most convenient method can be appropriately selected according to the scale of waste liquid treatment and the degree of treatment.
Although the preferred energization amount depends on the COD of the waste liquid to be treated, it is usually 0.5 MQ or more, preferably 1 to 10 MQ, more preferably 2 to 8 MQ per liter of photographic waste liquid (MQ is megacoulomb). .

  The photographic waste solution contains a surfactant derived from the photographic processing solution, but an antifoaming agent such as a nonionic surfactant can be further used to suppress foaming during electrolytic oxidation. For example, those from the Pluronic® series marketed by BASF, preferably Pluronic-31R1 Polyol® (methanol solution of a block copolymer of polyethylene oxide and polypropylene oxide) may be used. However, if an antifoam is used, it is used in the minimum amount necessary to avoid foam formation. For example, Pluronic-31R1Polyol (registered trademark) antifoaming agent may be added in an amount of 0.15 mL / treatment waste liquid L or less.

(Chemical oxidation treatment)
The chemical oxidation treatment of photographic processing waste liquid by the method of the present invention will be described.
<Chemical oxidizing agent and treatment>
The photographic waste liquor is directly subjected to a chemical oxidation treatment, that is, an oxidation treatment with a chemical oxidizer (referred to as an oxidizer) after or without adjustment of pH or the like. The oxidizing agent applied to the present invention may be any oxidizing compound that can oxidize a photographic developer, but preferred oxidizing agent and oxidation treatment use ozone, hydrogen peroxide or persulfate as the oxidizing agent. Oxidation treatment using chlorine, oxidation treatment using chlorine, and oxidation treatment using hypochlorous acid or a salt thereof. Further, if necessary, heating or ultraviolet irradiation may be performed during the oxidation process, or other oxidizing agents may be used in combination. The chemical oxidation treatment in the present specification refers to a treatment in which an oxidizing agent can decompose and oxidize reducing components and organic components in photographic waste liquid to some extent. Preferable chemical oxidation treatment is ozone oxidation treatment, hydrogen peroxide oxidation treatment, combined treatment of these with ultraviolet irradiation, and persulfuric acid treatment.

  The above-mentioned chemical oxidation is considered to proceed mainly due to oxidation behavior of hydroxy radicals, perhydroxy radicals, active oxygen groups, etc., and prior to chemical oxidation of the waste liquid, it is preliminarily brought to a pH range convenient for the action of these oxidizing groups. It is convenient to adjust so that the oxidation treatment can proceed efficiently. A preferred pH range is 8-12.

<Ozone oxidation>
The ozone aeration process is described.
The ozone oxidation method is performed by injecting ozone-containing air guided from an ozonizer (ozone generator) into a photographic waste solution. As one aspect of the injection method, there is a form in which treated water is introduced into a container that efficiently transmits ultraviolet light, and ozone is supplied to the bottom of the container, for example, through a glass ball filter (pore diameter 40 to 50 μm) or an atomizer. .

  In order to generate ozone, methods such as silent discharge, corona discharge, or electrolytic reaction are employed. However, any ozone generator used in the present invention can be used. There is no restriction, and it can be used by selecting from commercially available ozone generators. Among them, a method using silent discharge is preferable. Silent discharge refers to a discharge phenomenon that occurs in the gap when an AC high voltage is applied between two electrodes via a dielectric. A part of oxygen intervening in the space is discharged into ozone during discharge. Change. The dielectric is usually made of glass, the space is several millimeters, and the voltage is from several thousand volts to 50 to 500 cycles of AC to about 20,000 volts in some cases.

  Examples of the ozone generator include a flat electrode group of opposing electrodes, and a cylindrical ozone generator tube arranged in a vertical type or a horizontal type, and any of them can be used in the present invention. The raw material may be either oxygen or air, but in the present invention, it is cheaper and preferable to use air.

It is also preferable to perform irradiation treatment with ultraviolet light together with injection of ozone-containing air. When ultraviolet light is irradiated simultaneously with ozone supply, ozone is activated and oxidation efficiency is improved. The ultraviolet light is irradiated from a light source such as a mercury lamp installed at the bottom, inside or around the container. Mercury lamps are classified into low pressure, high pressure, and ultra high pressure according to the mercury vapor pressure inside the lamp, and emit far ultraviolet emission line, near ultraviolet emission line, near ultraviolet value, visible spectrum, and ultraviolet continuous spectrum, respectively. Any type can be used for the purpose of the present invention, but it is preferably combined with a low-pressure mercury lamp since the excitation wavelength region of ozone gas is strong in the far ultraviolet region (UV-C). Another preferred combination is an ultraviolet fluorescent tube (called a black light) that emits fluorescence in the 300 to 400 nm wavelength region when excited by a mercury emission line in the far ultraviolet region and an oxidation that absorbs the fluorescence and performs photocatalysis. A light irradiation / photocatalyst / ozone oxidation method in which ozone oxidation is performed in combination with titanium is also preferable. In any case, the oxidizing agent is ozone, and since ozone has a high free energy, the reaction is slow, so as a catalyst for promoting the reaction, irradiation with light in the ultraviolet region (UV-C) or titanium oxide and black light light. Irradiation is used.
The amount of power of the irradiation light varies depending on the COD value and the decomposability of the waste liquid component, but as a guideline, it is preferably 5 WHr to 600 WHr, more preferably 20 WHr to 500 WHr with respect to the waste liquid amount 100 kg.

Appropriate amount to be decomposed by ozone gas oxidation is 10% or more of COD in the waste liquid, preferably 15 to 90% of COD, and most preferably 20 to 80%.
The aerated ozone-containing gas may be exhausted as it is, but it is preferable to circulate and increase the utilization rate.
The exhaust gas from the ozone oxidation treatment apparatus is exhausted after being treated with ozone collection liquid such as thermal decomposition or sulfite aqueous solution.

Regarding the treatment with ozone and ultraviolet light, water treatment technology Vol. 32, No. 1, page 3 (1991), industrial water No. 349, page 15 (1987), ACS Symposium Ser. (Am. Chem. Soc.) No. 259 195 (1984).
Further, the waste liquid ozone oxidation method described in JP-A-7-47347 and the waste hydroxylation method in which ozone aeration is performed while irradiating with ultraviolet rays described in JP-A-5-968295 can also be used.

<Hydrogen peroxide oxidation>
Chemical oxidation can also be performed using hydrogen peroxide instead of ozone. Hydrogen peroxide is injected into the waste liquid as a 3%, 10% or 28% aqueous solution. Although it is possible to use the product in the form of an aqueous solution having a hydrogen peroxide concentration of 35, 50 or 60% as it is, it is preferable to dilute it to the above concentration for safety. Also in the case of chemical oxidation with hydrogen peroxide, the preferred degree of oxidation is the same as the oxidation rate described above for ozone.
Hydrogen peroxide is less oxidatively active than ozone, but in this case as well, it is effective to promote contact oxidation by light irradiation or a combination of light irradiation and photocatalyst (titanium oxide). Greater than the promotion effect on The ultraviolet light source and the photocatalyst to be combined are also applicable to ozone.
For the treatment with hydrogen peroxide, the technique described in JP-A-9-234475 can also be used.

As one form of the photographic waste solution using hydrogen peroxide, the Fenton oxidation method can be used in the present invention. This oxidation method uses the oxidizing power of hydrogen peroxide. However, as described above, hydrogen peroxide has a large free energy, but its electron transfer is slow, so the oxidation rate is limited. As an oxidation method using ferrous salt in combination. This catalytic action is characterized in that high COD substances having poor biodegradability are also effectively decomposed.
Specifically, the Fenton method is performed at a hydrogen peroxide concentration of 0.5 to 10 mol / L, ferrous sulfate 100 to 200 mmol / L, pH 2 to 3, and an initial temperature of 10 to 30 ° C.
As a specific example of the waste water treatment method using the Fenton method, for example, JP-A-3-262594 can be cited. As a similar catalytic oxidation method using hydrogen peroxide as an oxidizing agent, there can be mentioned a waste water treatment method using iron powder as a catalyst described in JP-A-4-235786.
Further, another catalyst that can be used for the oxidation treatment using hydrogen peroxide is described in JP-A-9-234475.

Preferable chemical oxidation treatment methods include oxidation treatment with persulfuric acid, chlorine and hypochlorous acid in addition to the above chemical oxidation treatment.
When hypochlorous acid is used, it is preferable to use sodium salt or ammonium salt, so-called bleached powder (calcium hypochlorate / calcium chloride / hydrate). In the present specification, the term "hypochlorous acid" includes the salt form.
These are all commercially available.
The temperature at the time of performing the chemical oxidation treatment using these oxidizing agents may be room temperature or a course, or may be adjusted by adjusting the temperature within an appropriate range of 30 to 90 ° C. In particular, in the case of oxidation with persulfate, the treatment is accelerated by heating.
On the other hand, in order to reduce the organic substance concentration in the waste liquid in a short time, it is necessary to increase the concentration of the oxidizing agent. However, in the case of high concentration oxidation, the oxidant in the processed photographic waste liquid tends to remain, which is not preferable. In that case, it is preferable to take a sufficiently long stirring time after oxidation under a high-concentration oxidant to make the reaction time sufficiently long.
For the treatment with chlorine and / or hypochlorous acid, techniques described in JP-A No. 53-41055 can be used.
For the persulfate oxidation treatment, techniques described in JP-A-61-230144 can also be used.

(Removal of halide and removal of silver)
The photographic waste solution contains silver derived from a light-sensitive material in the form of a silver thiosulfate complex salt or the like, but since silver is a valuable resource, it is desirable to collect it in advance. However, since silver thiosulfate complex (fixed silver) is harmless to animals and plants, there is no problem even if a small amount of silver remains. As a silver recovery method, any of the methods usually used for silver recovery of photographic waste liquid can be applied.
Preferred silver recovery methods include metal substitution methods and electrolysis methods. As the metal substitution method, an iron substitution method and an aluminum substitution method are used, and the iron substitution method is more preferable. In particular, a silver recovery method using steel wool is widely used, and a commercially available silver recovery apparatus is widespread, simple, and silver. A collection network with a collection company is also possible, which is preferable.
As an electrolytic recovery method, electrolytic silver recovery devices for photographic waste liquid are commercially available. Since the waste liquid after electrolysis has the advantage that it can be reused, it is convenient for reusing the fixing solution and the bleach-fixing solution, but steel wool is used for the purpose of the present invention as a fertilizer. The metal substitution method used is most preferable in terms of simplicity.
Halides derived from photosensitive materials and derived from processing liquid formulations contained in photographic waste liquids are composed of alkali metal salts and ammonium salts of chlorine ions, bromine ions and a small amount of iodine ions. These halides are required in very small amounts, but if present in excess, they can be removed or removed to a concentration that will not adversely affect soil consolidation or have a detrimental effect on plant growth. It is preferable to use it diluted. With respect to chloride ions, recent studies have shown that a supply of 1-10 kg per 1000 m ² (10a) per year is required. As a means for removing halogen ions such as chlorine ions, any known method can be used. However, it is practical to collect halogen ions using an ion exchange membrane electrodialysis method or an ion exchange resin. For ion-exchange membranes and ion-exchange resins, monovalent-selective membranes or resins may be used for the purpose of removing halides, but photographic waste liquid contains sulfates and sulfites in addition to halides. In some cases, an ion exchange membrane or an ion exchange resin capable of removing these anions may be selected. However, it is necessary to remove the anion component so that the pH of the waste liquid does not become excessively alkaline.

(Addition and adjustment of fertilizer ingredients)
Phosphorus compounds that can be used by adding to photographic waste liquor or photographic waste liquor that has been subjected to electrolytic oxidation or chemical oxidation treatment include potassium phosphate, magnesium phosphate, phosphoric acid, and other phosphorous fertilizers that are commonly used as phosphorous fertilizers. Examples thereof include acid lime, heavy superphosphate, bitumen superphosphate, calcined phosphorus fertilizer, and precipitated lime phosphate. These phosphorus compounds may be added to the photographic waste liquid and then other necessary components may be added and adjusted, or may be mixed simultaneously with the photographic waste liquid and other necessary additives.
The waste liquid from which silver and halide have been removed, and preferably a phosphorus compound added, can be used as it is as a liquid fertilizer, but it is preferable to further prepare the components. The component preparation is performed by selecting from adjustment of pH, addition of a trace component to be added, adjustment of a specific component concentration, and adjustment of a fertilizer form.

  The pH is adjusted to a pH range that does not adversely affect the growth of the plant, and is adjusted to a pH range of 3.5 to 9, preferably a pH range of 4 to 8.5. In the process of removing halides from the photographic waste liquid, the pH of the waste liquid often shifts to alkalinity regardless of whether an ion exchange membrane or an ion exchange resin is applied. . In order to avoid an increase in ionic strength, it is preferable to adjust the pH by using an organic acid such as acetic acid and citric acid instead of an inorganic acid, carbon dioxide, or acidic soil such as acidic clay. Furthermore, in the case where the fertilizer is mixed with the base material, acidic among the base materials, for example, peat moss (pH 3.5 to 4.5) and water paste (pH 4.5 to 5.0) should be used. Also good.

In addition to the three elements described above, the fertilizer can be further enhanced in function as a fertilizer by adding trace components necessary for plant growth. Such trace components include, as essential elements, calcium, magnesium and sulfur in addition to the above three elements, and calcium and sulfur are contained in the photographic waste liquid.
The trace essential elements are iron, manganese, copper, zinc, molybdenum, boron and chlorine, and iron and chlorine are contained in the photographic waste liquid.
Other useful elements include silicon, sodium, cobalt, nickel, aluminum and selenium, but photographic waste liquid generally contains sodium.
Trace essential elements and trace useful elements are elements that are always present in nature, and it is not necessary to intentionally supply all of the above elements, but they are suitable as fertilizers for specific trace element compounds as necessary. The addition amount can be added to the electrolytic waste liquid / phosphorus compound-containing composition that has been subjected to electrolytic treatment.

In order to use the photographic waste solution according to the present invention (itself, electrolytically oxidized, chemically oxidized) as a fertilizer, the photographic waste solution can be used as it is, or an appropriate amount of a phosphorus compound can be mixed, but the concentration of a specific component can be further increased. It is preferable to adjust the concentration of the three elements nitrogen, potassium and phosphorus, and to adjust other components as necessary. For the adjustment of the three elements, an appropriate component ratio is selected depending on the purpose of use, that is, the type of fertilizer.
For adjustment of the component concentration, for example, to correct the nitrogen component, urea or ammonia water is added.To correct the potassium component, potassium chloride is added. You may do it.
The mixing ratio and concentration of each fertilizer component are diverse because appropriate ratios and concentrations are selected depending on the plant to which the fertilizer is applied and the purpose of fertilization. For example, in a general-purpose basic compound fertilizer called a so-called 5: 5: 5 fertilizer, nitrogen, phosphoric acid, and potassium components are mixed in a ratio suitable for plant growth. For fertile soil with flowers and fruits, 5: 5 fertilizer containing phosphoric acid and potassium components is made.

<Form of fertilizer>
As adjustment of a fertilizer form, the adjustment according to the usage form of liquid fertilizer or solid fertilizer is mentioned first.
As the form of liquid fertilizer, a stock solution supply form, a diluted use liquid form and the like are used, and concentration adjustment such as vacuum concentration and water dilution and selection of a storage container are performed according to each use form.
In the case of a solid fertilizer, solidification such as spray drying or vacuum evaporation drying or granulation described later is performed according to the product form such as powder or granule. Examples of the solidified product include powders, granules, and tablets.
The powder form is produced by a method of adjusting the particle size by drying and solidifying if necessary, a method of pulverizing by appropriate drying such as spray drying, and the like.
The powder can be produced by a general method described in JP-A-54-133332, British Patents 725892, 728862, German Patent 3733861, and the like.
The solid fertilizer, that is, the concentrated solid fertilizer, is preferably in a granulated form, and the granulation method will be described later by being included in the granulation method of the soil improver.
In the case of solid fertilizer, the liquid fertilizer prepared above is solidified as it is, and the form of the granulated concentrated solid agent and the base material are solidified and then solidified. Selected.
In the form of the solid fertilizer mixed with the base material, the base material is selected from the base materials for the soil conditioner, so that it will be described as being included in the base material for the soil conditioner.
As a use form of the fertilizer of this invention, it is also a preferable application form to use as a soil improvement agent containing a fertilizer.

(Soil conditioner)
As a soil improver, the aspect which impregnated the above-mentioned liquid manure to the base material, the aspect which mixed the above-mentioned solid fertilizer to the above-mentioned base material, the granule or powder of the above-mentioned base material, and the above-mentioned liquid fertilizer were kneaded and granulated Although a form etc. are preferable, it is not limited to these.
The base material refers to fertilizers, moisture, and air carriers that have desirable physical properties for plant growth. Soil and soil modifiers that have excellent air permeability, fertilizer retention, and water retention, such as perlite, permiculite, red crust, Kanuma soil, compost, humus, peat moss, water-absorbing polymer, synthetic and / or natural zeolite, synthetic and / or natural white clay, fresh water, gelatin, wood chips and ground wood chips. Examples of the water-absorbing polymer include hydrophilic acrylic acid polymers such as polyacrylic acid and acrylic acid / methyl acrylate copolymer, and cellulose derivatives such as carboxymethyl cellulose, hydroxyethyl cellulose, and hydroxymethyl cellulose.

A particularly preferable form of the solid fertilizer and the soil conditioner is a form obtained by kneading and granulating the fine particles or powder of the base material and the liquid fertilizer. The mixing ratio may be any ratio as long as the base material and the adjusted waste liquid are stably impregnated and mixed without precipitation / separation, but as a granulation method, the liquid fertilizer / base material mass ratio is 0.00. 1 to 1 are used for fertilization and dilution as a thick fertilizer, and those with a mass ratio of 10 ^{−4 to} 0.1 are used in combination with a soil conditioner as a fertilizer and when growth is poor. A mass ratio of 10 ⁻⁸ to 10 ⁻⁴ can be used as a soil conditioner for the purpose of enhancing fast-acting fertility.

<Granulation>
In the present invention, a method of kneading and granulating the fine particles or powder of the substrate and the above liquid fertilizer, and a method of granulating and providing a coating layer for protection on the particle surface are known various granulation methods. Can be done by. Various granulation methods applicable to the present invention are described in the granulation handbook (edited by Japan Powder Industry Technical Association), and for example, JP-A-51-61837, JP-A-54-155038, JP-A-52- It can be produced by a general method described in the specifications of 88025 and British Patent No. 1213808. Further, it is also described in JP-A-4-221951 and JP-A-2-109043. Among them, as a preferable method, methods described in detail in JP-A Nos. 2001-183780 and 2001-183779 can be used. That is, for the granulation method, paragraphs [0018] to [0027] in JP-A-2001-183779 and examples, paragraphs [0021] to [0028] in JP-A-2001-183780 and examples, and processing agent containers are used. The methods described in JP-A-2001-183779, paragraphs [0029] to [0033] and JP-A-2001-183780, paragraphs [0030] to [0034] can be used.
However, in the present invention, the granulation method is not limited to these.

  In the present invention, the compression granulation method and the compacting method are remarkably effective in the present invention, and the coating on the granulated particle surface is a rolling granulation method, a fluidized bed granulation method, a coating granulation method, A coating granulation method using a centrifugal fluid type coating machine is preferred.

  The granule of the present invention can be coated on the surface thereof with a water-soluble polymer as necessary. There are no restrictions on the type of water-soluble polymer used for coating, such as gelatin, bectin, polyacrylic acid, polyacrylate, polyvinyl alcohol, modified polyvinyl alcohol, polyvinyl pyrrolidone, polyvinyl pyrrolidone / vinyl acetate copolymer , Polyethylene glycol, carboxymethylcellulose sodium salt, hydroxypropylmethylcellulose, hydroxyethylcellulose, hydroxypropylcellulose, methylcellulose, ethylcellulose, alginate, xanthan gum, gum arabic, tragacanth gum, caraya gum, carrageenan, methyl vinyl ether / maleic anhydride copolymer, etc. , One or more kinds selected from semi-synthetic and natural water-soluble polymer substances can be used. Ji glycol, polyvinyl pyrrolidone, hydroxypropyl cellulose, methyl cellulose, gum arabic, be used alone or in combination of carrageenan and more preferred in the present invention.

  The coating amount of the water-soluble polymer is not particularly limited as long as it is a coating amount that is usually performed, but is preferably 0.001 to 10% by mass and particularly preferably 0.01 to 5% by mass with respect to the granule. Although known methods can be used for the water-soluble polymer coating method without any particular restriction, the above-mentioned rolling granulation method, stirring granulation method, fluidized bed granulation method, coating granulation method, melt granulation method Alternatively, it is preferable to use a spray drying granulation method. Among them, a method in which a 1-50% aqueous polymer solution is spray-coated on the granule surface by a tumbling granulation method, a fluidized bed granulation method, a coating granulation method or a spray granulation method and dried is particularly preferable.

[Photo processing solution]
Although the present invention relates to the use of the resulting photographic waste liquid used in photographic processing, the photographic processing liquid in the previous stage as the waste liquid may be any kind and form of photographic processing liquid.

Photographic processing solutions include color processing solutions, black-and-white processing solutions, reducers for plate making operations, and developing processing tank cleaning solutions. Black-and-white developing solutions, color developing solutions, fixing solutions, bleaching solutions, bleach-fixing solutions, and image stabilization Liquid and the like. In addition, there are various photographic processing solutions for each type of photosensitive material such as color negative, color reversal, color paper, black and white photosensitive material, and printing system photosensitive material. Each photographic processing solution uses a photographic processing solution prepared in a developing laboratory, a mixed processing agent produced by a photographic processing agent supplier, a kit form or a single agent form, but the photographic waste liquid of the present invention. Any of these recycling methods can be summarized.
[Photosensitive material]

  Next, the photosensitive material that is the subject of photographic processing will be described. The photosensitive material according to the present invention is a color photographic photosensitive material for photographing such as a color negative film and a color photographic material for printing such as color photographic paper which are widely used in the photographic market as described above in relation to the object and background of the invention. Therefore, the present invention is preferably applied to a processing waste solution produced by processing these photosensitive materials, and these photosensitive materials are provided with at least one photosensitive layer on a support. A typical example is a silver halide photographic light-sensitive material having at least one photosensitive layer comprising a plurality of silver halide emulsion layers having substantially the same color sensitivity but different sensitivity on a support. It is.

  The silver halide photographic emulsion that can be used in the present invention is, for example, Research Disclosure (hereinafter abbreviated as RD) No. 17643 (December 1978), pages 22 to 23, “I. Emulsion preparation and types”. No. 18716 (November 1979), 648, No. 307105 (November 1989), 863-865, and Grafkide, "Physics and Chemistry of Photography", published by Paul Monter Glafkides, Chimie et Phisique Photographiques, Paul Montel, 1967), "Photoemulsion Chemistry" by Duffin, published by Focal Press (GF Duffin, Photographic Emulsion Chemistry, Focal Press, 1966), "Manufacture and coating of photographic emulsions" by Zerikman et al. , Published by Focal Press (VL Zelikman, et al., Making and Coating Photographic Emulsion, Focal Press, 1964) and the like. Also preferred are monodisperse emulsions described in US 3,574,628, 3,655,394 and GB 1,413,748.

EXAMPLES Hereinafter, although an Example demonstrates this invention more concretely, these do not limit the scope of the present invention at all.
(Turf cultivation)
A commercially available lawn vegetation material Dom Turf (manufactured by Kojin) is arranged in 3 vertical 3 horizontal squares and placed in a wooden frame to constitute one pallet. Three pallets were used for each experimental level. After the first measurement and photographing 10 days after the purchase, the turf on each pallet was pruned and the height was adjusted, and the fertilization test was started.
(Use fertilizer)
A. (Example of the present invention) Using a small processing machine for over-the-counter processing [Digital Minilab FRONTIER350 (manufactured by Fuji Photo Film Co., Ltd.)], commercially available color paper (Fuji Color Paper super) using the processing agent CP-48S for Fuji Color Paper An overflow solution from each of the developing, bleach-fixing, and rinsing baths discharged after processing, that is, a mixed waste solution of development waste solution, bleach-fixing waste solution, and rinse waste solution was obtained. Steel wool was immersed in this waste liquid by a conventional method to remove silver ions in the waste liquid to 1 mg / liter or less, and then the pH was adjusted to 7.0 using sulfuric acid (diluted solution). The liquid was filtered with an oil adsorbent attack ace (manufactured by Ryoka Etec). When used as a fertilizer solution, it was diluted 100 times with tap water so that the nitrogen content was equal to that of commercially available fertilizer.
B (comparative example). Sample prepared in the same manner as A but omitting only the oil adsorbent treatment.
C (comparative example). Commercial fertilizer [Sumitomo liquid fertilizer for leaves, manufactured by Sumitomo Chemical Co., Ltd.] diluted 100 times.
D (comparative example). Type (without topdressing)

(Fertilization)
Each pallet was uniformly sprayed once a week at a ratio of 100 mL / m ² of fertilizer. Irrigation was performed every 2 days.
(Observation / Result)
The results were evaluated by measuring the color of the lawn and visual evaluation of the photographed print.

(1) Measurement of color ・ Color measurement method of lawn color To quantify the color change of lawn, using a color difference meter (Minolta color difference meter CS-100) of the stimulus value direct reading method, it is made of barium sulfate. The chromaticity values (Y, x, y) of the standard white surface and grass were measured.
On the day of the start of the test, in order to reduce the fluctuations in the measured values, aiming at the 4th, 6th, 9th and 13th weeks, select a sunny day, and measure from 11:00 to 13:00 on that day, and the measurement position It was defined to measure from a certain position. In addition, this device is a device that can measure chromaticity with a viewing angle of 1 degree, but in order to remove the fine structure of the turf and the influence of the shade, the measurement was performed with the focus shifted.
A color meter was set at a position of 100 cm from the front end of the front of each pallet and a height of 150 cm, and measurement was performed at 3 locations × 3 locations (9 locations in total) divided equally for each pallet.

A chromaticity value CIE1965 (L ^* , a ^* , b ^* ) based on a standard white surface made of barium sulfate was calculated from the obtained chromaticity value, and a color Hab ° was calculated based on this (colorimetry). Based on the values, L ^* , a ^* , b ^* , and Hab ° are calculated by the following formulas, which are general formulas used for colorimetric calculation, and are described in the Color Science Handbook: The Color Society of Japan).
Spectral tristimulus values determined by the International Color Difference Society (CIE) are calculated from the chromaticity values as follows.
X = x / yY
Y = Y
Z = (1-xy) / yY
The colorimetric values of the reference white plate are X ₀ , Y ₀ , Z ₀
The colorimetric values of the lawn are X, Y, Z If

L ^* = 116 (Y / Y ₀ ) ^1/3 −16
a ^* = 500 {(X / X ₀ ) ¹ /3-(Y / Y ₀ ) ^1/3 }
b ^* = 200 {(Y / Y ₀ ) ^1/3 − (Z / Z ₀ ) ^1/3 }
At this time, the colorimetric values of the reference white plate are X ₀ , Y ₀ and Z _0, and the colorimetric values of the lawn are X, Y and Z It was.
In order to express a change in color tone with one characteristic value, the chromaticity values L ^* , a ^* , b ^* of the CIE 1976 (L ^* , a ^* , b ^* ) chromaticity coordinate system are obtained, and the following values are obtained from these values. The hue represented by the formula (H _ab °) was determined.
H _ab ° = 180 / π x tan ⁻¹ (b ^* / a ^* )
However, when a ^* > 0 b ^* > 0, 0 ° <H _ab ° <90 °
When a ^* <0 b ^* > 0 90 ° <H _ab ° <180 °
When a ^* <0 b ^* <0 180 ° <H _ab ° <270 °
When a ^* > 0 b ^* <0 270 ° <H _ab ° <360 °
Table 1 shows the average values of the measured values (H _ab °) of nine grasses on each of the three pallets.

The color of the lawn is in the region of a ^* <0, B ^* > 0. The smaller the numerical value, the more yellowish the color, and the larger the value, the more blueish the color appears. As shown in Table 1, the samples A, B, and C are more bluish than when the fertilization is not performed (sample D), but the sample A according to the present invention from which tar is removed is most excellent, It was superior to Sumitomo liquid fertilizer (Sample C).

(2) Visual evaluation of photo prints As a means of recording the color change of the lawn, a digital still camera was also taken prior to measurement. The camera used was FinePix S2Pro manufactured by Fuji Photo Film Co., Ltd. The automatic light source color correction function was turned off, the image was fixed in “Sunny”, and the image data was saved in RAW format. At this time, a Macbeth chart was photographed under the same photographing conditions, and 24 colors were measured with the color difference meter.
The photographed image was corrected by a matrix operation so that the output value obtained from the Macbeth chart image taken at the same time and the colorimetric value measured by the color difference meter were matched, and then a digital print manufactured by Fuji Photo Film Co., Ltd. A comparative photograph was output by the device (Pictrogrphy3500).
From the photographed image results, it was confirmed that the fertilizer of Sample A had the effect of keeping the green of the lawn and making it difficult to turn yellow even after the 13th week when the temperature was lowered and the temperature decreased.

  In Example 1, the sample of the present invention and the comparative sample were prepared in exactly the same manner as in Example 1 except that the following electrolytic oxidation treatment was performed between the operation of removing silver from the waste liquid sample and the pH adjustment. Then, a fertilization test was conducted, and a visual evaluation of the photographic print was performed by photography.

(Electrolytic oxidation treatment)
Lead dioxide (made by Nippon Carlit Co., Ltd., LD400) is used for the anode, stainless steel (SUS-316) is used for the cathode, and 10 L of waste liquid is put into a 15 L tank in which three cathodes and two anodes are alternately mounted in parallel and electrolyzed. . The area of each electrode was 200 cm ² , the distance between the electrodes was 25 mm, and the waste liquid was subjected to electrolytic oxidation treatment for 15 hours at 100 A while stirring with a stirrer.

(result)
The observation result of the photographed image shows that the samples A, B, and C are more bluish than when the fertilization is not performed (sample D), but the lawn treated with the fertilizer of the sample A according to the present invention from which tar has been removed is It was confirmed that the effect of keeping the green of the lawn and making it difficult to turn yellow was superior to the lawn of the other samples even after the 13th week when the leaves looked green and the temperature decreased.
When the examples of the present invention were compared with each other, the result was that the lawn sample of Example 2 was visually superior in blueness. This is presumed to be because the excess iron salt concentration accompanying electrolytic oxidation was reduced, and organic substances and organic acids unnecessary for plant growth were more effectively decomposed.

  In Example 1, the sample of the present invention and the comparative sample were prepared in exactly the same manner as in Example 1 except that the following chemical oxidation treatment was performed between the operation of removing silver from the waste liquid sample and the pH adjustment. A fertilization test was then conducted and a visual evaluation of the photographic prints was made by photography.

Ozone was supplied through a ball filter at a rate of 100 mg / hr per liter of the photographic waste liquid, and the treatment was performed for 10 hours.
The equipment used is as follows:
Ozone generator: FM-300N, Nikko Metal Ball filter: caliber 2G, 25mmφ, manufactured by Kinoshita Rika

Ultraviolet (UV) light was irradiated through ozone ventilation. The container used was a quartz cell for photochemical reaction.
The equipment used is as follows:
UV light generator; 450W high-pressure mercury lamp (UM-453 type, UM-453BA type as a stabilizer, manufactured by USHIO)

(result)
The observation result of the photographed image shows that the samples A, B, and C are more bluish than when the fertilization is not performed (sample D), but the lawn treated with the fertilizer of the sample A according to the present invention from which tar has been removed is It was confirmed that the effect of keeping the green of the lawn and making it difficult to turn yellow was superior to the lawn of the other samples even after the 13th week when the leaves looked green and the temperature decreased.
Moreover, when the examples of the present invention were compared with each other, the results showed that the lawn sample of Example 3 was visually superior to the lawn sample of Example 1. The reason for this is presumed that, as described above, the excessive iron salt concentration accompanying chemical oxidation is reduced, and organic substances and organic acids unnecessary for plant growth are more effectively decomposed.

Claims (12)

  A fertilizer obtained by removing tar or a tar precursor from a photographic waste liquid and adjusting the component concentration as necessary.   The fertilizer according to claim 1, wherein the fertilizer is obtained by removing tar or a tar precursor from a photographic waste liquid by adsorbing the tar or a tar precursor to the oil adsorbent.   The fertilizer according to claim 1, wherein the fertilizer is obtained by removing tar or a tar precursor from a photographic waste solution by adsorbing the tar or a tar precursor on an oil adsorption film.   The fertilizer according to any one of claims 1 to 3, wherein the fertilizer is obtained by subjecting a photographic waste solution to electrolytic oxidation treatment and removing tar during or after the oxidation treatment.   The fertilizer according to any one of claims 1 to 3, wherein the fertilizer is obtained by subjecting a photographic waste solution to chemical oxidation treatment and removing tar during or after the oxidation treatment.   The photographic waste solution from which the tar precursor has been removed is obtained by subjecting the photographic waste solution to electrolytic oxidation treatment or chemical oxidation treatment, but adjusting the component concentration as necessary. Fertilizer.   The fertilizer according to any one of claims 1 to 6, wherein the silver contained in the photographic waste liquid is recovered in addition to the removal of the tar or the tar precursor.   The fertilizer according to any one of claims 1 to 7, wherein the fertilizer is subjected to a treatment for reducing the concentration of halide in the photographic waste liquid in addition to the removal of the tar or the tar precursor.   The fertilizer according to claim 8, wherein the treatment for reducing the concentration of halide is an electrodialysis treatment using an ion exchange membrane or an ion exchange resin treatment.   A soil improver comprising the fertilizer according to any one of claims 1 to 9 in a base material. The substrate is selected from pearlite, permiculite, red crust, kanuma clay, compost, humus, peat moss, water-absorbing polymer, synthetic and / or natural zeolite, synthetic and / or natural clay, moss, gelatin, wood chips and ground wood chips The soil conditioner according to claim 10, wherein the soil conditioner is at least one.   A method for reusing photographic waste liquid, wherein the fertilizer according to any one of claims 1 to 9 or the soil conditioner according to claim 10 or 11 is obtained using the photographic waste liquid.