JP2949357B2 - Method and apparatus for evaporative concentration of photographic processing waste liquid - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for improving a concentration rate and a thermal efficiency in evaporative concentration of a photographic processing waste liquid.

[Background of the Invention]

Generally, photographic processing of silver halide photographic materials is performed by developing, fixing and washing with black-and-white photographic materials, and color development, bleach-fixing (or bleaching and fixing), washing with water and stable with color photographic materials. The process is performed by combining processes using a processing solution having one or more functions such as chemical conversion.

In a photographic process for processing a large amount of photosensitive material, components consumed by the process are replenished, while components that are eluted or concentrated in the processing solution by the process (e.g., bromide ions in a developing solution, fixing solution). Means to maintain the performance of the processing solution constant by removing the processing solution components by removing the silver complex salt), and a replenisher is replenished to the processing solution for the above replenishment.
A part of the processing solution is discarded for removing the thickening component in the photographic processing.

In recent years, the replenisher has been changing to a system in which the amount of replenisher has been greatly reduced for pollution and economic reasons, including washing water, which is a replenisher for washing, but wastewater for photographic processing has been removed from the processing tanks of automatic developing machines. It was guided by a waste liquid pipe, diluted with a waste liquid of washing water, cooling water of an automatic developing machine, and the like, and disposed of in a sewer.

However, due to the recent tightening of pollution regulations, washing water and cooling water can be disposed of in sewers and rivers. However, other photographic processing solutions [eg, developing solutions, fixing solutions, color developing solutions, bleach-fixing solutions] (Or bleaching solution, fixing solution), stabilizing solution, etc.]
Has become virtually impossible to dispose of. For this reason, each photographic processing company asks a specialized waste liquid processing company to collect the waste liquid by paying a collection fee, and installs pollution treatment equipment. However, the method entrusted to a waste liquid treatment company requires a considerable amount of space for storing the waste liquid, and is extremely expensive in terms of cost. Furthermore, pollution treatment equipment requires initial investment (initial cost). It is extremely large and has drawbacks such as requiring a fairly large area for maintenance.

More specifically, as a pollution treatment method for reducing the pollution load of the photographic processing waste liquid, an activated sludge method (for example, JP-B-51-12943 and JP-B-51-7952, etc.) and an evaporation method (Japanese Patent Laid-Open No. Nos. 49-89437 and 56-33996, etc.) and electrolytic oxidation method (JP-A-48-84462, JP-A-49-119458, JP-B-53-434).
No. 78, JP-A-49-119457, etc.)
Nos. 51-37704, JP-A-53-383, JP-B-53-43271, etc., reverse osmosis method (JP-A-50-22463, etc.), and chemical treatment methods (JP-A-49-64257, JP-B-49257) No. 57-37396,
No. 12152, No. 49-58833, No. 53-63763, JP-B-57-3
No. 7395) are known, but these are not yet sufficient.

On the other hand, due to restrictions on water resources, rising water supply and drainage costs, simplicity in automatic processor equipment, and the work environment around the automatic processor, etc. Processing using an automatic developing machine (so-called anhydrous washing automatic developing machine) which does not require piping for supplying and draining water for washing is becoming widespread. In such processing, it is desired that cooling water for controlling the temperature of the processing liquid is also omitted. In such photographic processing that does not substantially use washing water or cooling water, the pollution load is extremely large because the photographic processing waste liquid from the automatic developing machine is not diluted with water as compared with the case where there is a photographic processing waste liquid. is there.

Therefore, since the amount of the waste liquid is small, it is possible to omit the external piping for the supply and the waste liquid, which makes it difficult to move after the installation because the piping which is considered to be a drawback of the conventional automatic developing machine is installed. The space is small, the piping work at the time of installation requires a great deal of cost, the disadvantages such as the need for energy for hot water supply pressure are eliminated, and the compactness and simplification are achieved until it can be used as an office machine. Benefits are demonstrated.

However, on the other hand, the effluent has an extremely high pollution load, and the effluent is becoming completely impossible in rivers and even sewers in light of the pollution regulations. Further, although the amount of waste liquid in such photographic processing (processing using a large amount of running water and not washing with water) is small, even a relatively small color processing lab, for example, is about 10 per day.

Therefore, it is generally collected by waste liquid recovery companies, and secondary and tertiary treatment is performed to make it harmless.
In a mini-lab or the like, the collection efficiency is low, so that it is difficult to have them come to the collection, and there is a problem that the store is filled with waste liquid.

On the other hand, in order to solve these problems, the photographic processing waste liquid can be easily processed in a mini lab, etc.
It has been studied to heat photographic processing waste liquid to evaporate water to dryness or to solidify it, for example, as disclosed in Japanese Utility Model Laid-Open No. 60-70841. According to the study by the inventors, when photographic processing waste liquid is evaporated, harmful or extremely odorous gases such as sulfurous acid gas, hydrogen sulfide, and ammonia gas are generated. This is commonly used as a fixer or a bleach-fixer for photographic processing solutions such as ammonium thiosulfate and sulfite (ammonium salt,
(Sodium salt or potassium salt) is generated by decomposition due to high temperature. Further, during the evaporating process, the water and the like in the photographic processing waste liquid gasify as described above, thereby expanding the volume and increasing the pressure in the evaporator. As a result, the harmful or odorous gas leaks out of the evaporating apparatus to the outside of the apparatus due to this pressure, which is extremely unfavorable in the working environment.

In order to solve these problems, Japanese Utility Model Laid-Open No. 60-70841 discloses a method in which an exhaust gas treatment section such as activated carbon is provided in an exhaust pipe of an evaporative treatment apparatus. However, this method has a serious drawback in that water vapor due to a large amount of water in the photographic processing waste causes condensation or condensation in the exhaust gas processing section, and the water absorbs the gas-absorbing agent and instantaneously loses the gas-absorbing ability. Therefore, it was not yet practically usable.

In order to solve these problems, the present applicant has provided cooling condensing means for condensing vapor generated by evaporation when evaporating photographic processing waste liquid, further processing condensed water generated by condensing, and adding non-condensable components. A method and an apparatus for treating a photographic processing waste liquid which is also processed and discharged to the outside have been previously proposed.

However, according to the above proposal, it has been found that there are the following problems. That is, the steam generated by the evaporation process is condensed by the cooling and condensing means, but if the cooling and condensing efficiency is low, the ratio of the steam that is not condensed and is sent to the outside of the device increases, and even if the steam is treated with activated carbon,
The rate at which odorous and harmful gases are released to the outside of the device also increases. Furthermore, condensed water condensed by the cooling condensing means,
Even if it is treated with activated carbon, it may be at the time of disposal, or it may not be possible to discharge it directly to sewage, etc. due to its high pollution load.

Further, in a minilab, the space in a store is extremely limited, and not only is the odor generated by processing the photographic processing liquid particularly problematic, but also the installation space of the waste liquid processing apparatus itself. In addition, the price and running cost of the apparatus are also important issues. Therefore, a compact, inexpensive, low-cost, high-concentration processing apparatus that can process photographic wastewater without generating odorous and harmful gas is desired. Have been.

[Problems to be solved by the invention]

As described above, it is desirable that the photographic processing waste liquid be immediately evaporated and concentrated on demand in the vicinity of the automatic processing machine. However, in order to solve this problem, the present applicant uses a heat pump as proposed in JP-A-63-151301.
By using the heating part and cooling part for heating for evaporative concentration and cooling of generated steam and generated gas, power consumption is reduced to 50%.
%, And succeeded in making it considerably lower. But,
In the laboratory, not only large power is consumed for evaporating and condensing the photographic processing waste liquid, but also large power is consumed for controlling the temperature of each processing liquid of the automatic processing machine and heating or cooling the drying unit. Thus, there is a demand for a further reduction in heating / cooling power when viewed comprehensively. Especially
If it consumes more than 30A, the cost of drop-in wiring will also increase considerably.

In view of the above, an object of the present invention is to provide a method and an apparatus for evaporating and concentrating photographic processing waste liquid, which further increase the thermal efficiency and improve the processing capacity in evaporating and concentrating the photographic processing waste liquid.

[Means for solving the problem]

This objective is achieved by the following technical means (a), (b), (c),
(D) is achieved.

(A) A method for evaporating and concentrating a photographic processing waste liquid by heating and evaporating and concentrating a photographic processing waste liquid using a heat pump, and cooling and condensing the resulting vapor to liquefy the photographic processing waste liquid, wherein the generated vapor is brought into contact with an acidic substance. A method for evaporating and concentrating a photographic processing waste liquid characterized by the above.

(B) A method for evaporating and condensing photographic processing waste liquid, wherein the evaporation and the cooling and condensation of vapor in the method of (a) are performed under reduced pressure.

(C) an evaporative concentration column for evaporating and condensing photographic processing waste liquid by a heating section of a heat pump, means for condensing vapor by a cooling section of the heat pump in a condensing section communicating with the column, and means for supplying photographic processing waste liquid to the column. An apparatus for evaporating and condensing photographic processing waste liquid, comprising: means for supplying an acid substance; and means for contacting generated acid with the acid substance.

(D) The apparatus for evaporating and concentrating photographic processing waste liquid according to the above mode (c), further comprising a decompression means for depressurizing the evaporating and concentrating column and the condensing section communicating therewith.

[Action]

The acidic substance of the present invention may be a solid substance or an aqueous solution and has a pH value of 5.0 or less.For example, sulfuric acid, hydrochloric acid, phosphoric acid, nitric acid, boric acid, carbon dioxide, inorganic acids such as sulfamic acid and acetic acid. Carboxylic acids such as oxalic acid, citric acid, malonic acid and tartaric acid; aminopolycarboxylic acids such as ethylenediaminetetraacetic acid and nitrilotriacetic acid; organic phosphonic acids; and acid salts such as sodium hydrogen sulfate. Is a compound that releases

In the present invention, the acidic substance is preferably an aqueous solution.
This is because an aqueous solution can be easily supplied by a pump or the like if it is to be supplied into the evaporation concentration column.

As a contact method, there is a method in which a container and / or a sponge-like or cloth-like aqueous solution holding substance is provided on the concentrated waste liquid level in the evaporation concentration column, and an acidic substance is supplied thereto.

There are a method of taking out the acidic substance out of the system and a method of putting it in a concentrated waste liquid, and the latter is more preferable.

In addition, a method was considered in which an acidic substance holding means was provided in a vapor passage between the evaporative concentration column and the steam cooling / condensing section, and an acidic substance was supplied thereto. And in that case, it goes out of the system of the used acidic substance, in the concentrated waste liquid, or in the concentrated liquid.

Further, the acidic substance holding means may be provided in a concentration column.

A method is also effective in which the acidic substance is dropped on a heat pump refrigerant pipe in the condensing section.

Further, it is effective to provide a means for mixing an acidic substance with the condensate and circulating the mixture in the condensing section.

When the pH of the waste liquid is 7.5 or more, the present invention is particularly effective, and when it contains a fixing component, it is more effective. The amount of the acidic substance used in the present invention is preferably an amount capable of releasing 0.01 mol or more of hydrogen ions per photographic waste liquid to be processed, and more preferably 0.01 to 10%.
A supply of an amount capable of releasing more than mol.

If the amount is small, the effect of the present invention becomes insufficient, and if the amount is large, the amount used increases, which has a problem in terms of cost and exerts various effects.

These implementations will be described in more detail in the following examples.

〔Example〕

First, in finding the method of the present invention, the following experiment was conducted using an evaporative concentrator as schematically shown in FIGS. 1 (a), (b), (c) and (d).

EXPERIMENTAL EXAMPLE 1 Commercially available ASA100, 400 films made by Konica, Fujifilm and Kodak as color negative films were processed according to the following processing process specifications and processing solution specifications.

However, two tank counter currents (45 seconds, 2
Tank) and 3 stabilization tanks counter current (20 seconds,
(3 tanks).

 The composition of the processing solution used is as follows.

[Coloring phenomenon tank liquid] Potassium carbonate 30 g Sodium hydrogen carbonate 2.5 g Potassium sulfite 4 g Sodium bromide 1.3 g Potassium iodide 1.2 mg Hydroxylamine sulfate 2.5 g Sodium chloride 0.6 g 4-Amino-3-methyl-N-ethyl-N -(Β-hydroxylethyl) aniline sulfate 4.8 g Potassium hydroxide 1.2 g Add water to make 1 and adjust to pH 10.06 with potassium hydroxide or 50% sulfuric acid.

[Color developing replenisher] potassium carbonate 40 g sodium hydrogen carbonate 3 g potassium sulfite 7 g sodium bromide 0.5 g hydroxylamine sulfate 3.1 g 4-amino-3-methyl-N-ethyl-N- (β-hydroxylethyl) aniline sulfate 6.0 g Potassium hydroxide 2 g Add water to make 1 and adjust to pH 10.12 with potassium hydroxide or 20% sulfuric acid.

[Bleaching tank solution] Ferric ammonium 1-3-propylenediaminetetraacetate 150 g Acetic acid (90% aqueous solution) 50 ml Ammonium bromide 150 g Water is added to 1 to adjust the pH to 4.4 using ammonium water or glacial acetic acid. .

[Bleaching replenisher] The bleach tank solution was adjusted to pH 4.2 with acetic acid.

[Fixing tank solution and replenishment] Ammonium thiosulfate 250 g Ammonium sulfite 20 g Exemplified [A'-7] (ammonium salt) 3 g Add water to make 1 and adjust the pH with acetic acid and ammonia water
Adjust to 6.8.

[Stable tank solution and replenisher] Formaldehyde (37% solution) 1 ml 5-Chloro-2-methyl-4-isothiazolin-3-one 0.05 g Emulgen 810 1 ml Sodium formaldehyde bisulfite adduct 2 g The pH was adjusted to 7.0 with water and 50% sulfuric acid.

Further, the color paper was treated with the following treatment steps and treatment liquid.

Processing process Temperature Time Replenishment amount Number of tanks (1) Color development 38 ° C 30 seconds 200ml / m ² 1 tank (2) Bleaching and fixing 33 ° C 25 seconds 100ml / m ² 1 tank (3) Stabilization 33 ° C 30 seconds 500ml / m ² Three tanks (Note 1) (Note 1) The three-layer method is a counter current method.

Processing solution composition [Color developing tank solution] triethanolamine 10 ml potassium sulfite 0.2 g sodium chloride 1.5 g potassium carbonate 32.0 g 3-methyl-4-amino-N-ethyl-N- (β-methanesulfonamidoethyl) -aniline sulfate Salt 5.5 g Optical brightener (diaminostilbene) 1.0 g Diethylhydroxylamine 5.0 g Diethylenetriaminepentaacetic acid 3.0 g Potassium bromide 2 mg 1,2-Dihydroxybenzene-3,5-disulfonic acid-sodium salt 0.2 g Add water The total amount is set to 1 and the pH is adjusted to 10.15 with KOH and H ₂ SO ₄ .

[Color developing replenisher] The amount of 3-methyl-4-amino-N-ethyl-N- (β-methanesulfoaminoethyl) -aniline sulfate in the color developing tank solution was 7.0 g /, and potassium bromide was zero. And p
The H value is set to 10.60.

[Bleaching and fixing tank solution and replenisher] Ethylenediaminetetraacetic acid ferric ammonium dihydrate 60 g Ethylenediaminetetraacetic acid 3 g Ammonium thiosulfate (70% solution) 140 ml Ammonium sulfite (40% solution) 27.5 ml Potassium carbonate or glacial acetic acid at pH 5.8 And add water to bring the total amount to 1.

[Stabilizing tank and Replenisher] 1-hydroxyethylidene-1,1-diphosphonic acid _{2g Bicl 3 0.3g ZnSO 4 · 7H} 2 O 0.7g fluorescent whitening agent (diamino stilbene) 1.0 g Keison WT (Note) 0.5 g (Note ) Rohm and Haas Co. The waste liquid obtained by the above treatment is used alone or mixed,
As will be described in detail later, concentration treatment was performed using the waste liquid treatment apparatus shown in FIG. 1, and the waste liquid treatment speed at that time was measured.

In the above measurement, the amount of waste liquid decreasing was measured every 30 minutes, and the average value of 2 hours was taken.

Then, the waste liquids obtained by the development processing of the negative film and the color paper are integrated into one waste liquid, and FIGS. 1 (a), (b), (c), and (d).
The evaporation concentration rate was measured using an evaporation concentration apparatus using the method of the present invention shown in FIG. At that time, a sodium hydrogen sulfate solution was used as the acidic substance. The replenishment position and replenishment method of the acidic substance aqueous solution in the evaporating and concentrating apparatus are as follows.
There are three means shown in FIGS. (A), (b) and (c), and the evaporative concentration rates in each case were measured.

Here, an embodiment of an evaporative concentration apparatus using the method of the present invention will be described with reference to the schematic diagrams of FIGS. 1 (a), 1 (b) and 1 (c).

First, the description will be made from the points common to the schematic diagrams (a), (b) and (c).

A photographic processing waste liquid is injected and stored in a vacuum evaporation column (hereinafter simply referred to as a column) 1 which can withstand reduced pressure.
A decompression means 7 is connected to the upper vapor condensing section 5 to reduce the pressure. It is known that boiling occurs below its own boiling point under reduced pressure lower than atmospheric pressure. In this embodiment, evaporation at a low temperature where gas generation does not easily occur is performed under this reduced pressure. Next, 3
A heating means 2 having a two-dimensional arrangement is provided.
The lower part is immersed in the photographic processing waste liquid storage part 4 so as to heat the photographic processing waste liquid, and the upper part is in the air protruding from the photographic processing waste liquid storage part. Into the waste liquid storage tank 31 and the acidic substance solution storage tank 75.
From the liquid feed means 3, 3 'by the electromagnetic valves 6A and 76 so that the acidic substance solution is mixed with the waste liquid vapor fed and in the column, and in addition to the heating and evaporation under reduced pressure, during the spray dropping process Heat evaporation is repeated to efficiently and rapidly perform concentration.

The water evaporated here contributes to downsizing and stabilization of reduced pressure in the column by providing a cooling means 8A, a condensed water guide and a water receiver 8C at the upper part in the column 1. On the other hand, a component solidified to a high concentration by repeating the above evaporation and concentration is received and collected in a container 12 connected to a lower portion of the column 1. The reason why the heating means 2 is three-dimensionally arranged in the liquid and in the air in the present invention is that the part in the liquid mainly preheats the photographic processing waste liquid, and the part in the air has a large contact area with the photographic processing waste liquid sprayed and dropped thereon. This is effective in uniformly and efficiently performing low-temperature evaporation without gas generation. Further, a cooling means 8A is provided in the upper part of the column 1 so as to capture the water vapor rising from the lower part, cool and condense the water vapor, and collect it as water droplets. This has the effect of reducing the decompression balance in the column 1 due to the generated steam and reducing a large load to maintain a specified decompression state in the decompression device 7 (in this embodiment, an ejector is used). . That is, the place where the pressure in the column 1 rises due to the generated steam is immediately cooled and condensed to suppress the pressure rise.

In this configuration, assuming that the submerged portion of the heating means 2 is at the optimum temperature for the reduced-pressure evaporation, the portion in which the heating means 2 is in the air at the same temperature is also managed. The actual surface temperature of the portion of the photographic processing liquid becomes high, and when the photographic processing liquid is in contact with the photographic processing liquid, unpleasant gas is generated due to rapid heating. The means may be controlled to a temperature equal to or lower than the gas generation temperature, or the heating means may be separately controlled in the liquid or outside the liquid to an appropriate temperature.

Further, the heating means 2 and the cooling means 8A may be any of known techniques, but a heat pump is used in the present invention. Then, water vapor comes into contact with the surface of the cooling means and condenses to form water droplets, which travels through the cooling means 8A and is collected in the water recovery container 9. The surface temperature of the heating means is preferably 10
It is most preferably 0 ° C or lower, particularly preferably from 20 ° C to 60 ° C.

The heat radiating part of the heat pump is used as the heating means 2, and the heat absorbing part of the heat pump is used as the cooling means 8 A and the cooling means 8 B provided in the water recovery container 9.

A charge pipe 25 for charging a condenser of a heat pump constituting the heating means 2 and a capillary tube serving as an expansion valve provided after the heating means 2
26, a compressor 21 for the refrigerant disposed on the out side of the cooling means 8A, an empty condenser 22 for air-cooling and condensing the refrigerant, and a fan 24 and a fan motor 23 of the column 1
Is placed outside.

Further, the refrigerant evaporator of the upper vapor condensing section 5 in the column 1 is connected to the cooling means 8B in the water recovery container 9 from the capillary tube 26 through the condenser of the heating means 2 and further extended as cooling means 8A. Is returned to the compressor 21 outside the column 1 connected to the compressor.

The cold water in the water recovery container 9 is supplied to a water circulation pump (P-
2) The water connected to the decompression device (ejector) 7 by 33 and drawn through the pipe 34 from the condensate recovery port 8C of the vapor condensation section 5 at the top of the column 1 is put into the water recovery container 9 and simultaneously depressurized in the column 1. To do.

Water overflowing from the water recovery container 9 is sent to a water tank 35 by a pipe 36. And this is drained to sewage.

In this way, since a relatively simple heat pump liquefies a large amount of vaporized vapor and a small amount is exhausted from the exhaust port 36A, odor is completely prevented.

Although the evaporative concentration apparatus of the present embodiment is as described above, when considering only the thermal efficiency and the concentration rate without considering the generation of odor and the like, almost the same as when the pressure is reduced even when the pressure reducing apparatus is stopped. Obtain thermal efficiency and concentration rate. However, in such a case, the processing waste liquid and the pH adjusting liquid are transferred from containers 31 and 75 to column 1.
It is necessary to use a pump instead of the electromagnetic valves 6A and 76 in order to pump in.

The amount and time of replenishment of the photographic processing waste liquid into the column 1 are determined based on detection information of the level sensor (LC) 64.

In FIG. 1 (a), a container 74 is provided above the liquid level of the evaporative waste liquid in the evaporative concentration column, and an acidic aqueous solution is supplied thereto.

FIG. 1 (b) shows a case in which the impregnated cloth 76 is provided in the container 74 in the case of FIG. 1 (a), and an acidic substance aqueous solution is supplied thereto.

FIG. 1 (c) shows an evaporative concentration column 1
The acidic substance solution is supplied to the pipe 8A of the heat pump cooling section of the steam condensing section 5 which communicates with the acidic substance solution.

The solution is stored in the pool 8C together with the condensate. In the case of FIG. 1 (C), the supplied solution can be circulated to some extent between the condensing section and the drainage tank by the ejector of the condensed liquid by the electromagnetic valve 39. In FIGS. 1 (a), (b) and (c), the acidic substance solution is stored in a storage tank.
From 75, the electromagnetic valve 76 is operated so that the required amount passes through the liquid feeding means 3 'and can be supplied and replenished from the supply port 71 at the tip of the pipe. Of course, in the case where the concentration column 1 and the concentration section communicating therewith are not decompressed, the column must be replenished with a pump.

FIG. 1 (d) shows a vapor concentrator in which an acidic substance solution is not supplied.

Table 1 shows the results of measuring the evaporation and concentration rate using such an apparatus.

In this way, when the acidic substance solution is supplied into the vapor, the rate of evaporation and concentration is significantly improved by nearly 50% as compared with the case where the solution is not supplied.

The results of experiments using the apparatus of the present invention with respect to the method of the present invention will be described above. However, another embodiment of the evaporative concentration apparatus using the method of the present invention will be described with reference to the schematic diagram of FIG. Will be explained. Here, components having the same functions as those in the first embodiment will be described using the same symbols.

The column 1 capable of withstanding the reduced pressure is provided with the liquid reservoir 4, the heating unit 2A of the heat pump, and the liquid pumping belt 51 from the liquid reservoir 4 independently. Further, a vapor condensing section 5 and a reservoir section 8C of distilled water are provided adjacent to the column 1. A cooling section 8A of a heat pump is provided in the steam condensing section 5, and a high temperature steam duct 41 communicating with an upper portion of the column 1 is provided above the cooling section 8A. The heating section of the heat pump is provided in the duct 41.
2C and a fan 42 are provided, and steam is circulated from above the cooling unit 8A to the column 1 by the fan 42 through the duct 41, and the heating unit 2C works with air during the circulation. The temperature is set to be high.

A heating unit 2B of the heat pump is provided outside the liquid reservoir 4 in the column 1 in series with the heating unit 2A.

As a result, the waste liquid on the belt circulated while being pumped by the pumping belt 51 is immediately evaporated by a part of the heated steam in the duct 41 and the help of the heated air, and the steam condensation efficiency is improved. Will be.

A heat pump is used as a heat source and a cooling source,
The high-pressure heating refrigerant compressed by the compressor 21 is supplied to the heating section 2
C, 2A, and 2B are connected in series, and out of the column 1, the fan 66
Capillary tube acting as expansion valve while being cooled
It is vaporized through 26, reaches the cooling section 8A, and returns to the compressor 21 described above.

Although the depressurizing means is omitted in FIG. 2, it is better to provide it in the same manner as in the embodiment shown in FIGS. 1 (a), 1 (b) and 1 (c) to reduce odor evaporation and the like. It can be said that it is more preferable for prevention. However, when the odor or the like is not taken into account, the pressure reducing means is not particularly required.

In this embodiment, the photographic processing waste liquid and the acidic substance solution are fed into the column 1 by pumps (P) from the containers 63 and 73.
This is performed under the condition shown in FIG. 2 by passing through the pipes of the liquid supply means 3 and 3 'from 62 and 72, and setting the supply ports 61 and 71 of the pipes at the upper part of the column 1. .

The time of the amount of replenishment is determined based on the detection information of the level sensor (LC) 64.

That is, the supply port 71 at the end of the acidic substance solution liquid supply pipe is directed toward the acidic substance solution receiving container 78 provided in the vapor passageway located between the upper part of the evaporative concentration column 1 and the upper part of the vapor condensing part 5. The solution is ready for injection. The receiving container 78 is held in a vapor passage, so that the evaporating vapor and the circulating high-temperature vapor passing therethrough are always in contact with the solution.

By using the apparatus of this embodiment, the applicant of the present invention can use the apparatus shown in FIGS. 1 (a), (b) and (c) to evaporate and concentrate the waste liquid obtained in the above-mentioned experiment. It was confirmed that the same good results as described above were obtained.

〔The invention's effect〕

In the evaporation and concentration of the photographic processing waste liquid, the method and apparatus of the present invention for adding an acidic substance solution to the waste liquid greatly improved the evaporation concentration rate. Therefore, the energy efficiency improved by using the heating unit and the cooling unit of the heat pump as the heating source for the evaporation concentration and the cooling source for the steam concentration, respectively, is further improved.

[Brief description of the drawings]

1 (a), 1 (b) and 1 (c) are schematic diagrams of an embodiment of the evaporative concentration device of the present invention, FIG. 1 (b) is a schematic diagram of an evaporative concentration device which is not the present invention, and FIG. The schematic diagram of another Example of the evaporative concentration apparatus of this invention. 1 Evaporation concentration column 2, 2A, 2B, 2C Heating section of heat pump 3, 3 'Liquid supply means 4, Liquid pool section 5 Condensing section, 6A, 76 Electromagnetic valve 8A … Heat pump cooling unit 21… Compressor, 31, 63… Waste liquid storage tank (container) 41… High temperature duct, 42, 66… Fan 51… Pumping belt, 61, 71… Tip supply port 62, 72 Pump 73,75 Acid solution storage tank

Continuation of front page (58) Surveyed field (Int.Cl. ⁶ , DB name) C02F 1/04 B01D 1/00 G03D 3/00

Claims (4)

(57) [Claims] 1. A method for evaporating and concentrating a photographic processing waste liquid by heating and evaporating and concentrating a photographic processing waste liquid using a heat pump, and cooling and condensing the resulting vapor to liquefy.
A method for evaporating and concentrating photographic processing waste liquid, wherein the vapor generated by the method is brought into contact with an acidic substance. 2. A method according to claim 1, wherein the evaporation and the cooling and condensing of the vapor are performed under reduced pressure. 3. An evaporative concentration column for evaporating and condensing photographic processing waste liquid by a heating section of a heat pump, means for condensing vapor by a cooling section of the heat pump in a condensing section communicating with the column, and supplying photographic processing waste liquid into the column. An evaporating and concentrating apparatus for a photographic processing waste liquid, comprising: means for supplying an acidic substance; and means for causing generated steam to contact the acidic substance. 4. An apparatus for evaporating and condensing photographic processing waste liquid according to claim 3, further comprising a decompression means for decompressing said evaporating concentration column and a condensing section communicating therewith.