JPH0248089A - Waste liquid processing device and automatic photograph developing machine using this device - Google Patents

Abstract

PURPOSE:To allow the reutilization of processing water and to facilitate processing of a residual waste liquid by obtaining the processing water for dissolution of ice contg. less contaminants and the thick waste liquid of the contaminants in the state in which the ice deposited by cooling the waste liquid generated by a development processing machine to the freezing point or below and the waste liquid coexist. CONSTITUTION:The cooled waste liquid freezes by a small amt. each on the surface of a drum, parts from the liquid surface and is scraped by a scraper 13. The scraped liquid enters a processing water tank 14. A heater 15 in the lower part of the scraper 13 and the tank 14 thaws partly or fully the ice. The waste liquid of a waste liquid receiving tank 12 is then removed into a thick liquid tank 17 at the point of the time when the waste liquid in an original liquid tank 8 runs out for the purpose of a batch processing. The liquid is transferred into a processing water stock tank 28 if the water quality of the liquid stored in the tank 14 is adequate for releasing or recycling. The liquid is transferred to the tank 8 and the similar operation is repeated when said quality is insufficient. The liquid in the tank 27 is transferred to a thick liquid stock tank 19 when the quality of the water stored in this tank attains the sufficient concn. The liquid is transferred into the tank 8 and the similar operation is repeated at the point of the time when the tank 17 is filled with the liquid if said quality is insufficient.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an apparatus for effectively treating silver salt photographic processing waste liquid.

/ In recent years, the processing time for silver halide photography has become shorter and can now be processed within 30 minutes. Furthermore, most of the time required from the time a user sends the photographed film to the DPE agency until the user receives the print is the round trip time between the DPE agency and the development processing facility called a laboratory. For this reason, it was necessary to speed up this process, so a small automatic developing machine that was automatically controlled and easy to handle was developed.
(hereinafter referred to as a mini lab) can now be installed. However, since there is generally no wastewater treatment equipment in such locations, minilabs are designed so that no wastewater is generated, and exhausted developer, fixer, and washing solutions are stored in waste tanks and treated periodically by a processing company. We have adopted a system to collect information. However, collection takes time and is surprisingly difficult in congested areas, and conversely, collection efficiency is poor in depopulated areas, leading to illegal disposal and the potential for contamination of the Kawano Seawater. For this reason, one of the themes on the minilab side is the development of machines that generate less waste liquid.
Currently, it is difficult to reduce the amount below a certain level because it may affect the quality of the photo. In a typical minilab (processing 30 rolls of 33 mm roll film per hour), the amount of waste liquid generated is approximately 3 liters of developing waste liquid, 2 liters of bleach-fixing waste liquid, and 10 liters of washing liquid per 7 days, totaling about 1 J liter.

The present invention can reduce the amount of waste liquid generated from these minilabs, reduce the collection of waste liquid, and perform waste liquid treatment that leads to cost reduction.

Table 1 shows the ingredients of typical photographic processing chemicals. In general, the treated wastewater shown in the photo has a high degree of pollution, and BOD (biochemical oxygen demand) and C0D (chemical oxygen demand) have PPM on the other hand, and this can be solved by general wastewater treatment such as the activated sludge method. Purification requires extremely large equipment, and many components cannot be biodegraded, making it impractical to install them in a minilab. Furthermore, even if activated carbon is used, a large amount of activated carbon is required due to adsorption capacity limitations, and it is also impractical due to the frequency and cost of replacement. The use of oxidizing agents such as ozone has been considered, but this is insufficient because many photographic processing chemicals have components that cannot be decomposed by ozone. Although there is a method of processing using a separation membrane, photographic processing chemicals contain a large amount of inorganic salts, and at the same time, the molecular weight of organic substances ranges from several tens to about 7,000, and there is currently no membrane that can efficiently separate these substances. Although the method of incinerating waste liquid can decompose COD components, the sulfur components in the chemicals generate a large amount of sulfur dioxide gas, iron, and salt dust, which must be disposed of, making it difficult to treat small amounts of waste liquid. It would be a complicated piece of equipment, and it would be impractical to install it alongside a minilab. The method of evaporating or distilling the waste liquid is that the chemical components are distilled out in the distillate and the COD
The removal rate is poor, at most about jO%, and the components decompose due to heat, producing foul-smelling gases, which require extensive treatment to remove, and have not been put to practical use. As described above, various studies have been conducted on photographic processing waste liquid, but a simple treatment method has not yet been found, and as a result, methods have been adopted in which the waste liquid is collected in minilabs or by processing companies.

As a result of consideration based on these facts, the present inventor found that the following processing method is a simple and feasible method.

That is, ice is precipitated from the waste liquid by cooling the photographic processing waste liquid to below O'C, and when ice is taken out from the waste liquid in a state where the waste liquid and the precipitated water coexist, ice with less contaminants and concentrated contaminants are obtained. It was discovered that the waste liquid can be efficiently separated. Generally, the method of obtaining a purified product by precipitating a solid from a liquid due to the difference in solubility due to temperature is a method often used as a crystallization operation, but this method is aimed at purifying a small amount of solute component, and the mother liquor of the present invention It is completely different from refining itself. An example of purifying the mother liquor itself is the production of fresh water from seawater, but this is a simple system of separating inorganic salts such as sodium chloride, and is different from the treatment of waste liquid as in the present invention. In other words, waste liquid is a complex thread containing various inorganic salts, complex salts, and organic substances that cannot be estimated at all by theory, and is generally not advantageous compared to other waste liquid treatment methods such as biological treatment and activated carbon treatment, so it is not recommended as a waste liquid treatment device. The words used! There's no way. However, as a result of experiments, we found that it has very good separation efficiency for processing waste liquid from photographic processing, and as mentioned above, it can be put to practical use without the problems of primary contamination caused by unremovable components and decomposed products that occur in other waste liquid treatment methods. I found it to be a worthy method. By repeating the same operation several times for the waste liquid obtained by this operation and the treated water obtained by melting the ice, a small amount of waste liquid with sufficiently concentrated pollutants and treated water purified to the extent that it can be discharged into rivers and sewers are obtained. Alternatively, it is possible to obtain treated water that has been purified to the point that it can be reused as washing water for photographic processing machines, and as a result, it has become possible to significantly reduce the amount of waste liquid sent to processing companies.

As representative examples of chemicals used in photographic developing machines, Table 1 shows the compositions of common color photographic developers and fixers. Photographic developing machines generate waste liquids such as developing waste liquid, fixing waste liquid, washing waste liquid, etc. Among them, washing waste liquid is generated the most, so when we measured the separation efficiency of the washing waste liquid for color photography, we found that The results shown in Table 2 were obtained. For comparison with this, the separation efficiency in simple distillation is shown in Table 3.

According to this, when ice is precipitated and removed in the presence of waste liquid, the separation efficiency is approximately three times that of simple distillation, and an effective result was obtained. Further, Table ≠ shows data for the case of black and white photographic waste liquid, and in this case too, results worthy of practical use were obtained. This indicates that it can also be applied to photographic waste liquid for printing and waste liquid from X-ray processing.

The present invention will be explained below with reference to the drawings.

FIG. 1 is a diagram showing an embodiment of the present invention, and (1) is a minilab. A developing waste solution (2), a bleach-fixing waste solution (3), and a washing waste solution (4) are generated from the minilab, and these are placed in each tank (5), (6), and (7). A large amount of washing waste liquid (4) is transferred to the raw liquid tank (8). The waste liquid receiver is sent from the raw liquid tank (8) by the pump (9) to a machine (hereinafter referred to as a refrigeration separator) consisting of a container, a cooling drum, a scraper, and other accessories (this unit is referred to as a refrigeration separator), and is placed under the cooling drum αυ. A certain waste liquid receiver is a container (2)
to go into. The waste liquid receiver of the cooling drum is partially immersed in the waste liquid in the container and rotates slowly in the direction of the arrow. The surface of the cooling drum is internally cooled to below 0° C. by a refrigerant or the like. Cooling methods include indirect cooling using antifreeze or refrigerant gas, and direct cooling using the Peltier effect. The cooled waste liquid gradually freezes on the drum surface, grows and separates from the liquid surface, is scraped off by the scraper α■, and enters the treated water tank (14).

Lower part of scraper α1 and treated water tank α→
A heater αυ is installed at the bottom of the ice cube to melt some or all of the ice. In the example shown in this figure, when the waste liquid in the stock solution tank is used up due to batch processing, the waste liquid receiver opens the valve (g) to concentrate the waste liquid in the container (b) and drains it to the liquid tank ←η.

If the quality of the liquid stored in the treated water tank ←Φ is such that it can be discharged or reused, it is transferred to the treated water stock tank α barrel. If it is insufficient, transfer the water from the treated water tank to the stock solution tank (8) and repeat the same operation. On the other hand, when the water quality of the liquid stored in the concentrate tank reaches a sufficiently concentrated concentration, the liquid is transferred to the concentrate stock tank σ9. If it is insufficient, once the concentrated liquid tank is full of liquid, transfer it to the stock liquid tank (8) and repeat the same operation. When freezing and purifying ice, what reduces the separation efficiency the most is the waste liquid that adheres to the ice, so it is effective to remove the adhering waste liquid by blowing air with an air knife.

FIG. 2 is a diagram showing an example in which a plurality of refrigeration separators are connected in series to continuously treat washing waste liquid, and the obtained treated water is reused as washing water. (1) to (7) are the same as in Figure 1, but washing waste liquid (4) is pumped (c).
The waste liquid receiver of the third stage refrigerating separator (c) is supplied to the container. The diagram from top to bottom shows the first to fifth stages of refrigerating separators. Each refrigerating separator has the structure explained in Fig. 1, and the refrigerating separators (e) to (c) are connected to the next stage refrigerating separator instead of the treated water tank shown in Fig. 1. In place of the concentrate tank αη in FIG. 1, a freezing separator in the previous stage is connected.

However, it is connected to the previous stage refrigeration separator by a U-shaped connecting pipe (c) with a slight level difference to prevent liquid mixing and backflow. The washing waste liquid freezes on the surface of the cooling drum of the third-stage freezing separator (c), is removed from the liquid by the rotation of the drum, is scraped off by a scraper, and is partially or completely dissolved, and then the waste liquid is sent to the seventh-stage freezing separator (c). The uke goes into the container. Here, the waste liquid receiver again deposits the waste liquid in the container and ice in a new solid-liquid equilibrium state on the surface of the ≠th stage cooling drum, and enters the 0th stage freezing separator (c) in the same manner. Ice or water discharged from the j-stage frozen separator (c) in a similar operation enters the treated water tank/distribution tank (b) since the third stage is the final stage.

In the tank (b), the ice is completely melted by the melting heater □□□, and a portion is supplied to the photographic developing machine as washing water by the pump (3I), the temperature of which is controlled by the temperature control heater (33). Also, some of it is due to the connecting pipe (E)!
It is returned to the stage refrigeration separator (c). The ratio of the amount of liquid returned to the outside of the system as washing water corresponds to the reflux ratio in distillation operation.In continuous operation, the waste liquid receiver at each stage keeps the concentration of waste liquid in the container constant, and the degree of purification and concentration is controlled. This is a deciding factor.

The concentrated liquid is concentrated in the second stage frozen separator (A), first stage frozen separator (A), and finally enters the concentrated liquid tank (C).

Examples are shown below.

Example 1 Table 5 shows the data obtained by continuously processing washing waste liquid using a refrigeration separator as shown in Fig. 2.

The specifications of the cooling drum used here are 10 cm in diameter.
length/! ; cm Surface area 0.0'l-7m2 Refrigerant temperature -g'C Rotation speed / times / 3 minutes Reflux ratio / The number of stages of the device is 5, and the water washing waste liquid is supplied to the third stage from the concentration side, so the throughput is 0 .3j liter/hour concentrate
0.03g liter/hour concentration C0Dcr/10.
000ppm treated water 0.31.2 liters/hour concentration 00Dcr/jOppm was obtained.

The present invention can treat waste liquid in this way, and the treated water can be discharged into rivers or sewers or reused as washing water for photographic processing machines, so the residual waste liquid is reduced, making it easier to collect and systemize. Easily dispose of waste liquid outside. However, depending on regulatory values, it may be effective to use activated carbon as a final treatment after the pollution load has been sufficiently reduced by the treatment according to the present invention, but this does not depart from the spirit of the present invention.

Since the treated water is still processed at low humidity, there is no change in quality due to decomposition of the contents due to heat, and there is no contamination due to the growth of algae or microorganisms, so it can be used as high-quality rinsing water for photo processing machines, and the rinsing water can be closed. becomes easier. Furthermore, in this case, it is not necessary to treat the wastewater to a low concentration as required by wastewater regulation values, so there is an advantage that it is simpler. Additionally, the process can be done without the foul odors caused by the decomposition of components or the sludge equipment associated with biological processing, which is seen in other processing methods.Considering that automatic photo processing machines are often placed in spaces not exclusively used for other tasks or where people are constantly present. This is a big advantage that cannot be overlooked. 1st expression solution formulation Bleach-fix solution per liter 2nd surface per liter Washing waste liquid separation efficiency: C0Dcr of washing waste liquid = 1, 2
000ppm-/3-lg=≠

[Brief explanation of the drawing]

The drawings show embodiments of the present invention; FIG. 1 is a schematic diagram of batch processing, and FIG. 2 is a schematic diagram of continuous processing. (1) is an automatic photo processor, (2) is a developer waste, (3) is a fixer waste, (4) is a washing waste, (5) is a developer waste tank, (6) is a fixer waste tank, and (7) is a waste fixer. Washing waste tank,
(8) is the raw solution tank, (9) is the pump, aQ is the frozen separator, aη is the cooling drum, (b) is the waste liquid receiver is the container, a is the scraping scraper, (b) is the treated water tank, is the heater, (2) is the pulp, Qη is the concentrate tank, α8)
0 is treated water stock tank, 0 is concentrated liquid stock tank, (a) is air knife, (c) is pump, (a) is /
Stage frozen separator, ■ is the first stage frozen separator, (c) is the third stage frozen separator, (c) is ≠ stage frozen separator, 0ej is j
Stage refrigeration separator, (Foundation) is treated water tank and distribution tank,
(c) is the concentrate tank, the handle is the U-shaped connecting pipe, the handle is the melting heater, (31) is the pump, 0 is the pipe, c33)
is a temperature control heater.

Claims (1)

[Claims] 1. In an automatic photographic processing machine, a means for cooling the generated waste liquid to below 0°C using a refrigerant, and removing the ice from the waste liquid in a state where the waste liquid coexists with ice that precipitates due to cooling. By using the difference between the contaminant concentration in the photographic processing waste liquid in a solid-liquid coexistence state and the contaminant concentration in the ice precipitated from the waste liquid, it is possible to compare the treated water with melted ice containing less contaminants and the contaminant. A waste liquid treatment device characterized in that it obtains a concentrated waste liquid. 2. An automatic photographic processing machine comprising a mechanism for recirculating the treated water generated from the waste liquid processing apparatus according to claim 1 as washing water in the automatic photographic processing machine.