JPH03267189A - Evaporation concentrating device for waste photographic processing liquid - Google Patents

Abstract

PURPOSE:To allow the stoppage of concentration at the point of an arbitrary concn. by averting a bumping phenomenon by evaporating and concentrating the concd. liquid in an evaporation concentrating column in a reduced pressure state while stirring the liquid and then detecting the resistance at the time of the stirring by the torque of a motor. CONSTITUTION:A pressure reducing means 7 is connected to an upper evaporation concentrating section 5 of the evaporation concentrating column 1 of the device which puts a specified amt. of a waste photographic processing liquid into the evaporation concentrating column 1 and evaporates this waste liquid to successively concentrate the liquid to reduce the pressure in the concentrating section. A heating means 2 which is three-dimensionally disposed is provided in the column 1. The heating means 2, the lower part of which is immersed into a storage section 4 for the waste liquid, heats the waste liquid. A heat pump is provided as a cooling means 8A in the upper part in the colum 1 to cool and condense the steam. The concd. liquid is stirred by a rotating body 162 connected to the motor 161. The torque of the motor 161 is detected and the stop of concentration and/or the discharge of the concentrate is commanded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to an evaporative concentration treatment device for photographic processing waste liquid, and in particular, the present invention relates to an evaporative concentration treatment device for photographic processing waste liquid, and in particular, it is used to collect photographic processing waste liquid generated from the development process of photographic light-sensitive materials using automatic processors. This invention relates to an apparatus for evaporating and concentrating photographic processing waste liquid, which is suitable for processing in or near an automatic processing machine without recovering it.

[Background of the invention]

In general, photographic processing of silver halide photographic materials includes development, fixing, washing, etc. in the case of black and white materials, and color development, bleach-fixing (or bleaching and fixing) in the case of color materials.
A combination of processes using a treatment liquid having one or more functions such as , water washing, and stabilization is performed.

In photographic processing in which a large amount of light-sensitive material is processed, components consumed during processing are replenished, while components that are eluted into the processing solution or concentrated by evaporation during processing (for example, bromide ions in the developer, bromide ions in the fixer), etc. A method is adopted to maintain the performance of the processing solution at a constant level by removing substances such as silver complex salts (such as silver complex salts) and keeping the processing solution components constant. A portion of the processing solution is discarded to remove thickening components during photographic processing.

In recent years, systems have been changing to systems in which the amount of replenishment fluid, including washing water, which is used as a replenishment fluid for washing, has been significantly reduced due to pollution and economic reasons, but photographic processing waste fluid is removed from the processing tank of automatic processors. The liquid was led through a waste pipe, diluted with waste liquid from washing water, cooling water from automatic processing machines, etc., and disposed of in sewers, etc.

However, due to stricter pollution regulations in recent years, it is possible to dispose of washing water and cooling water into sewers or rivers, but other photographic processing solutions [e.g. developer, fixer, color developer, bleach-fixer] (or bleaching solution, fixing solution), stabilizing solution, etc.] has become virtually impossible to dispose of. For this reason, each photo processing company pays a collection fee to a specialized waste liquid processing company to collect the waste liquid, or installs pollution treatment equipment. However, the method of outsourcing to a waste liquid treatment company is
A considerable amount of space is required to store the waste liquid, and it is also extremely expensive.Furthermore, the initial investment (initial cost) of pollution treatment equipment is extremely large, and it takes a large space to maintain it. It has drawbacks such as the need for space.

Furthermore, specifically, as a pollution treatment method for reducing the pollution load of photographic processing waste liquid, activated sludge method (for example, Japanese Patent Publication No. 51-12943 and No. 51-7952, etc.);
Evaporation method (JP-A-49-89437 and JP-A-56-339)
No. 96, etc.), electrolytic oxidation method (JP-A-48-84462,
49119458, JP 53-43478, JP 49-119457, etc.), ion exchange method (Japanese JP 51-37704, JP 53-383, JP 53-1985, etc.)
3-43271, etc.), reverse osmosis method (Japanese Patent Application Laid-Open No. 50-224
No. 63, etc.) Chemical treatment method (Japanese Patent Application Laid-Open No. 49-64257,
Japanese Patent Publication No. 57-37396, Japanese Patent Publication No. 53-12152, Japanese Patent Publication No. 4958833, Japanese Patent Publication No. 53-63763, Japanese Patent Publication No. 57-37395, etc.) are known, but these are still insufficient.

On the other hand, due to constraints from water resources, rising water supply and drainage costs, the simplicity of automatic processor equipment, and the work environment around automatic processors, in recent years, stabilization treatments have been used instead of washing with water, and Photographic processing using automatic developing machines (so-called waterless automatic developing machines) that do not require piping for water supply and drainage is becoming popular. In such processing, it is desired that cooling water for controlling the temperature of the processing liquid can also be omitted. In this type of photographic processing, which does not substantially use rinsing water or cooling water, compared to the case where there is photographic processing waste liquid from automatic processors, the pollution load is extremely large because it is not diluted with water, and on the other hand, the amount of waste liquid is small. be.

Therefore, due to the small amount of waste liquid, it is possible to omit the piping outside the machine for supplying and waste liquid, which is considered to be a disadvantage of conventional automatic processors, as it is difficult to move after installation. The disadvantages such as the small space required, the high cost of piping work during installation, and the high energy cost of hot water supply pressure have been eliminated, and the machine has been made compact and simple enough to be used as an office machine. Benefits are demonstrated.

However, on the other hand, the waste liquid has an extremely high pollution load, and in light of pollution regulations, it has become completely impossible to drain the waste liquid into rivers or even sewers. Furthermore, such photo processing (using a large amount of running water,
Although the amount of waste liquid in the process (processing without water washing) is small, for example, even in a relatively small-scale color processing laboratory, the amount is about 1OQ per day.

Therefore, waste liquid is generally collected by a waste liquid collection company and rendered harmless through secondary and tertiary processing.However, not only is the price of waste liquid collection increasing year by year due to rising collection costs, but collection efficiency is low in minilabs, etc., so it is difficult to do so. No one can come to collect the liquid, causing problems such as waste liquid filling the store.

On the other hand, in order to solve these problems, research has been conducted on heating the photographic processing waste liquid to evaporate the water to dryness or solidify it, with the aim of making it easier to process the photographic processing waste liquid even in minilabs. For example, Utsukai Showa 60-7084
It is shown in No. 1 etc. According to research conducted by the inventors, when photographic processing waste liquid is evaporated, harmful or extremely malodorous gases such as sulfur dioxide gas, hydrogen sulfide, and ammonia gas are generated. It has been found that this is caused by the decomposition of ammonium thiosulfate and sulfites (ammonium salt, sodium salt, or potassium salt), which are commonly used as fixing solutions and bleach-fixing solutions in photographic processing solutions, due to high temperatures. Further, during the evaporation process, moisture and the like in the photographic processing waste liquid becomes vapor and gasifies, thereby expanding the volume and increasing the pressure in the evaporation pot. Therefore, due to this pressure, the harmful or malodorous gas leaks out of the evaporation treatment equipment to the outside of the equipment.
Something extremely undesirable happens in the work environment.

Therefore, in order to solve these problems,
No. 1 discloses a method of providing an exhaust gas treatment section such as activated carbon in the exhaust pipe section of an evaporation treatment device. However, this method has the serious drawback that water vapor from a large amount of water in the photographic processing waste liquid condenses or condenses in the exhaust gas treatment section, covering the gas absorption processing agent and causing it to instantly lose its gas absorption ability. As such, it could not yet be used for Tora use.

In order to solve these problems, the present applicant et al. installed a cooling condensing means to condense the vapor generated by the evaporation when evaporating photographic processing waste liquid, and further treated the condensed water generated by the condensation and also processed the non-condensable components. We have previously proposed a method and apparatus for treating photographic processing waste liquid, which is also treated and discharged to the outside.

However, it has been discovered that the above proposal has the following problems. In other words, the vapor generated by the evaporation process is condensed by the cooling condensing means, but if the cooling condensation efficiency is poor, the proportion of vapor that is not condensed and is released outside the device increases, resulting in a bad odor even if treated with activated carbon. The rate at which harmful gases are released to the outside of the device also increases. Further, even if the condensed water condensed by the cooling condensing means is treated with activated carbon, it may be necessary to dispose of it, or it may be too polluting to be discharged directly into the sewage system.

Furthermore, the space available in minilabs is extremely limited, and not only is the bad odor generated by processing photographic processing solutions a particular problem, but also the installation space for the waste solution processing equipment itself becomes a problem. Furthermore, the price and running cost of the device are also important issues, so there is a need for a compact, inexpensive processing device that can process photographic processing waste liquid without emitting foul-smelling and harmful gases and has low running costs.

[Problem to be solved by the invention]

In order to solve these problems, the applicant has
No. 3-151301, etc., to make it possible to provide a concentrating device for photographic processing waste liquid that generates less bad odor from photographic waste liquid and that must be reliably treated. In this method, the evaporative concentration column of photographic processing waste liquid is placed in a reduced pressure state and the evaporation temperature is lowered to carry out evaporative concentration, and the generation of odor gas is extremely small and is virtually non-existent. However, when the evaporation temperature is lowered, bumping occurs due to the slightest trigger, resulting in a violent boiling state. In order to avoid this, the applicant has found that it is effective to use a means of stirring the concentrated waste liquid in the evaporative concentration column.

On the other hand, if the waste liquid is evaporated and boiled down without producing such a bad odor, the moisture will be removed and only solid matter will remain, which would be the most efficient in terms of volume, but would require a large amount of energy. and time consuming and undesirable. In addition, it may accumulate in the evaporation concentration column and become difficult to recover.

Therefore, it is better to stop the concentration and recover the concentration at an appropriate concentration. However, regarding this,
No. 2-118346 proposed various means for detecting concentration, but these methods were not very suitable due to the problem of heat balance with the heat pump.

The present invention solves these problems by evaporating and concentrating the photographic processing waste liquid under reduced pressure at the lowest heating temperature possible, and stopping the processing at a concentration that makes the waste liquid efficiently and easily recoverable in a concentration column without emitting any bad odor. An object of the present invention is to provide a vacuum evaporation concentrator for photographic processing waste liquid using a heat pump, which concentrates the concentrated waste liquid to a state where it can be recovered.

[Means to solve the problem]

This purpose is to provide an evaporative concentration device for photographic processing waste liquid in which a certain amount of photographic processing waste liquid is placed in an evaporative concentration column, and the waste liquid is evaporated and concentrated. It has a heat pump that constitutes a means for heating photographic processing waste liquid in the column and a means for cooling evaporated vapor, and a means for stirring the concentrated liquid in the column using a rotating body connected to a motor, and concentrates by detecting the torque of the motor. This is achieved by a photographic processing waste liquid evaporation concentration device characterized in that it issues a stop command and/or a concentrate discharge command.

〔Example〕

One embodiment of the present invention will be described using the sectional view of FIG.

A photographic processing waste liquid is injected and stored in a vacuum evaporation concentration column (hereinafter simply referred to as a column) 1 that can withstand reduced pressure, and the upper vapor condensing section 5 of the column 1 is equipped with a pressure reducing means 7 (in this example, two ejectors 7A). , 7B is used, but of course one series is also acceptable) to reduce the pressure. It is known that boiling occurs below the boiling point of the substance under reduced pressure lower than atmospheric pressure, and in the present invention, evaporation is carried out at a temperature of 60° C. or lower under reduced pressure. However, it is not limited to this. Next, a heating means 2 arranged three-dimensionally is provided in the column 1, and the lower part of the heating means 2 is immersed in the storage section 4 of the photographic processing waste liquid, so as to heat the photographic processing waste liquid. The upper part thereof protrudes from the storage part 4 for the photographic processing waste liquid and is in the air, and the photographic processing waste liquid is sucked into this part from the storage part 4 by a suction pump (P-3) 6.
With the liquid feeding means 3, as if spraying, in addition to heating evaporation under reduced pressure, heating evaporation during the spraying and dropping process is repeated, thereby achieving efficient and rapid concentration.

The water evaporated here is made to contribute to compactness and stabilization of the reduced pressure inside the column by providing a cooling means 8A, a condensed water guide, and a water receiver 8C at the upper part of the column 1. On the other hand, by repeating the above-mentioned evaporation concentration, the highly concentrated and considerably solidified components are collected and collected in a container 12 placed at the bottom of the column 1. In this invention, the reason why the heating means 2 is arranged three-dimensionally in the liquid and in the air is that the submerged part is mainly used to preheat the photographic processing waste liquid, and the aerial part increases the contact area with the photographic processing waste liquid that is sprayed onto it. It has the effect of uniformly and efficiently performing low-temperature evaporation without gas generation. Further, a cooling means 8 was provided at the upper part of this column 1 to capture the water vapor rising from the lower part, cool it, condense it, and recover it as water droplets. This is because the generated steam destroys the balance of pressure reduction in this column 1, and the pressure reduction device 7 (in this embodiment, two ejectors 7A and 7B are used, but it is also possible to use one series) to maintain the specified pressure reduction. This has the effect of reducing the heavy load placed on the body. That is, when the pressure within the column 1 increases due to generated steam, it is immediately cooled and condensed to suppress the pressure increase.

In this configuration, if the part of the heating means 2 in the liquid is set to the optimal temperature for the reduced pressure evaporation, the part of the heating means 2 that is in the air is also managed at the same temperature, and due to the difference in heat transfer effect, The actual surface temperature of the parts in the air will be high, and if the photographic processing waste comes in contact with this, unpleasant gases will be generated due to rapid heating, so the amount of photographic processing waste to be sprayed should be adjusted to The heating means may be kept below the gas generation temperature, or the heating means may be separately controlled inside and outside the liquid to maintain appropriate temperatures.

Further, the heating means 2 and the cooling means 8A may be any known technology, but in the present invention, a heat pump is used. Water vapor then comes into contact with the surface of this cooling means and condenses.
The water becomes droplets and is collected in the water collection container 9 through the cooling means 8A. The surface temperature of the heating means is preferably 10
The temperature is most preferably 0°C or lower, particularly 20°C to 60°C.

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

Now, when the pressure is reduced, it boils at a lower temperature, so the slightest trigger will cause a bumping phenomenon. Therefore, as a workaround, a stirring rotating body 162 is inserted inside the evaporation concentration column as shown in FIG. 1 and connected to a motor 161 outside the column to enable stirring. This made it possible to stably avoid the bumping phenomenon. As the concentration progresses in this way, the resistance of the concentrate also increases. As a result, the torque of the motor increases, so detect the torque value and understand the correlation between the torque value and the appropriate concentration in advance, and then concentrate when the torque corresponding to the concentration of concentrate that is convenient to collect is detected. This is to make it stop. At the same time, a command to discharge the concentrate will be issued. Motor 1
It is preferable to use a torque motor as the motor 61.

In this embodiment shown in FIG. 1, the concentrated liquid in the column 1 is circulated by the suction pump (P-3) 6 of the liquid supply means 3, and the concentration of the concentrated liquid in the entire system is made uniform. Furthermore, the column 1 is refilled with waste liquid from the treated waste liquid tank 31 using the pump (P-1) 6A. These concentrated liquid circulation path and waste liquid replenishment path are preheated by two heating means.

This preheating means 2A uses the heat radiation part of a heat pump,
Heating means 2 in column 1 or capillary tube 26
This is effective in increasing thermal efficiency and concentration efficiency.

In addition, controlling the pH of the supplied waste liquid to be neutralized to 4.5 to 7.5, more preferably 5 to 6, greatly improves the processing speed, so a pH adjusting agent is provided in the storage tank 41,
A bellows pump (P-4) 42 allows the waste liquid to be sent to the column 1.

In addition, in the present invention, as a means of increasing thermal efficiency and processing speed, it has been confirmed that a plurality of concentration columns can be used to separately concentrate the developer and other liquids to increase the effect. Additionally, the generated steam is brought into contact with an acidic substance.

In addition, the silicone antifoaming agent is effective in preventing odor, and the storage tank 51 is connected to the column l by the feed pump (P-5) 52.
will be replenished in a timely manner.

Furthermore, the column 1 is provided with an electrode type liquid level sensor (LC) 61, and can be controlled so that it can be washed with the supplied waste liquid. Further, a fence 62 for preventing the concentrated liquid from splashing is installed in the evaporation vapor passage section of the column 1.

In addition, a temperature sensor TC is installed in the heat pump pipe near the compressor 21, and the motor (
FM) 23 controls the ON/OFF of the air cooling fan 24 and observes the behavior of sludge formation due to temperature rise.

In addition, a solenoid valve 36 is provided in the exhaust hole at the top of the power ram, and adjusts the pressure reduction value to be constant according to the amount of evaporation.

In addition, a water tank 9, a waste liquid storage tank 31. A dust suction prevention filter 45 is provided at the bottom end of the pipe for pumping up the pH treatment tank 4L from the antifoaming agent storage tank 51.

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

Further, the capillary tube 26 passes through the heating means 2 and the two condensers and is connected to the cooling means 8B in the water recovery container 9, and its extension serves as the cooling means 8A of the upper vapor condensing section 5 in the column 1. It is connected to the refrigerant evaporator and returned to the compressor 21 outside the column 1.

The cold water in the water recovery container 9 is pumped through a water circulation pump (P-2).
) 33 to the pressure reducing device (ejector) 7, and the condensate recovery port 8C of the vapor condensing section 5 at the top of the column l.
The water drawn through the pipe 34 is put into the water recovery container 9, and at the same time, the pressure inside the column 1 is reduced.

Further, water overflowing from the water recovery container 9 is sent to a water tank 35 through a pipe 36. This is then drained into the sewer.

In this way, with a fairly simple heat pump, most of the evaporated vapor is liquefied and only a small amount is exhausted through the exhaust port 36, so that odors are completely prevented.

Now, at the bottom of the evaporative concentration column I, there is a concentrate outlet I.
A is provided, and a scraping rod 71 is provided at the outlet IA.

The extracted concentrate is collected in a collection container 12 as shown in FIG.

As an example of the scraping rod, for example, as shown in FIG. 2, a scraping rod with a handle 75 at the tip, a sealing rubber stopper 72 and scraping blades 71A, 71B, and 71G is fitted into the bottom of the concentration column 1. We have also produced one with good results. However, it is not limited to this.

〔Effect of the invention〕

According to the present invention, by evaporating and concentrating the concentrated liquid in the evaporative concentration column while stirring it under reduced pressure, it is possible to avoid the occurrence of bumping, and the resistance during stirring is detected by the motor torque, and the signal can be used to determine the desired concentration. It is now possible to stop the concentration at this point. It is now possible to stop and collect the concentrated liquid at a concentration that is particularly easy to collect.
Not only does it eliminate the generation of odor-producing gases, it is also easy to operate and handle, which has great effects.

[Brief explanation of drawings]

FIG. 1 is a sectional view of one embodiment of the present invention. FIG. 2 is a perspective view of the scraping rod of the concentrate extraction section. 1... Column IA... Scraping port 2...
・Heating means 3...Liquid feeding means 4...Liquid reservoir section 5...Part that cools and condenses moisture

Claims (1)

[Claims] In an evaporative concentration device for photographic processing waste liquid, in which a certain amount of photographic processing waste liquid is placed in an evaporative concentration column and the waste liquid is evaporated and concentrated, the evaporation concentration column, a pressure reducing means in the column, and a photographic processing unit for the column are provided. It has a heat pump that constitutes a waste liquid heating means and an evaporated vapor cooling means, and a stirring means for the concentrated liquid in the column using a rotating body connected to a motor, and detects the torque of the motor to issue a concentration stop command and/or An apparatus for evaporating and concentrating photographic processing waste liquid, characterized in that it issues a command to discharge concentrate.