JPH0577478B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Application Field] The present invention relates to an evaporative concentration device for waste liquid, and more particularly to an evaporative concentration device for, for example, photographic processing waste liquid, which has a simple structure, is compact, and has improved concentration efficiency. [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, fixing, etc.) in the case of color photographic materials. ), washing with water, stabilization, etc., using a processing liquid having one or more of the following functions. In photographic processing in which a large amount of light-sensitive material is processed, components consumed during processing are replenished, while components that are concentrated by elution or evaporation into the processing solution (for example, developing solution) are replenished. Measures have been taken to maintain the performance of the processing solution at a constant level by removing bromide ions in the fixer and silver complex salts in the fixer to keep the processing solution components constant.
A replenisher is added to the processing solution for the above-mentioned replenishment, and a portion of the processing solution is discarded to remove thickening components in 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 waste liquid was led through a waste pipe, diluted with waste liquid from washing water, cooling water from automatic processing machines, etc., and then disposed of in sewers, etc. However, due to the tightening of pollution regulations in recent years,
It is possible to dispose of washing water and cooling water into sewers or rivers, but photographic processing solutions other than these [e.g., developer, fixer, color developer, bleach-fixer (or bleach, fixer), stable liquid, 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 requires a considerable amount of space to store the waste liquid, is extremely expensive, and requires an initial investment (initial cost) for pollution treatment equipment. It has drawbacks such as being extremely large and requiring a fairly large area to maintain. Furthermore, specifically, as pollution treatment methods for reducing the pollution load of photographic processing waste liquid, activated sludge method (for example, Japanese Patent Publication No. 51-12943 and Japanese Patent Publication No. 51-7952, etc.), evaporation method (Japanese Patent Publication No. 51-12943 and No. 7952, etc.), No. 49-89437 and No. 56-
33996, etc.), electrolytic oxidation method (JP-A-48-84462, etc.),
No. 49-119458, Special Publication No. 53-43478, Japanese Patent Application Publication No. 1973
-119457, etc.), ion exchange method (Special Publication No. 51-37704)
No., Japanese Patent Publication No. 53-383, Special Publication No. 53-43271, etc.),
Reverse osmosis method (JP-A-50-22463, etc.), chemical treatment method (JP-A-49-64257, JP-A-57-37396, JP-A-53-12152, JP-A-49-58833, JP-A-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 that 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. It has characteristics. 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, which is difficult to move after installation. It eliminates the drawbacks such as the small leg space, the high cost of piping work during installation, and the high energy cost of hot water supply pressure, and is extremely compact and simple enough to be used as an office machine. Great advantages will be realized. However, on the other hand, the waste liquid has an extremely high pollution load, and it has become completely impossible to dispose of the waste liquid not only in rivers but also in sewers in light of pollution regulations. Furthermore, although the amount of waste liquid from this type of photographic processing (processing that uses a large amount of running water and does not involve washing with water) is small, for example, even a relatively small-scale color processing laboratory can produce waste liquid in a day.
It will be about 10. Therefore, it is generally collected by waste liquid collection companies and rendered harmless through secondary and tertiary treatment.
Not only is the price of collecting waste liquid rising year by year due to rising collection costs, but the efficiency of collection at minilabs and other facilities is poor, making it difficult to get people to come and collect the waste, leading to problems such as stores being filled with waste liquid. 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. This is shown in Utility Model Application Publication No. 1987-70841. In the research conducted by the inventors, when photographic processing waste liquid is evaporated,
Harmful or extremely foul-smelling gases such as sulfur dioxide, 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 apparatus to the outside of the apparatus, resulting in an extremely unfavorable working environment. Therefore, in order to solve these problems,
No. 70841 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. However, it was not yet possible to put it into practical 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. We have previously proposed a method and apparatus for treating photographic processing waste liquid, which also processes non-condensable components and discharges them 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, a high proportion of the vapor is released outside the device without being condensed, even if treated with activated carbon. The rate at which foul-smelling and harmful gases are released to the outside of the device also increases. Furthermore, even if the condensed water condensed by the cooling condensing means is treated with activated carbon, it may not be able to be discharged directly into the sewer system or the like because of its odor and high pollution load when it is disposed of. 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. Additionally, the price and running cost of the device are also important issues. Therefore, there is a need for a compact, inexpensive, stable processing device with low running costs that can process photographic processing waste liquid without producing foul-smelling and harmful gases. In order to meet the demands of the industry, the present applicant has developed a device for evaporating and concentrating photographic processing waste liquids as disclosed in Japanese Patent Application Laid-Open No. 151301/1983, by evaporating and concentrating photographic processing waste liquids under reduced pressure using a heat pump to minimize the odor generated. I made a suggestion to avoid it. However, in this apparatus, the evaporated vapor emitted from the evaporative concentration column is guided to a separately provided cooling column and condensed, which is undesirable because two columns are arranged side by side and take up space, which increases the size of the apparatus. On the other hand, regarding evaporative concentration devices for waste liquids other than photographic processing waste liquids, Japanese Patent Publication No. 56-36991 and Japanese Patent Publication No. 57
-28281 and German patent DE3404248A1. Japanese Patent Publication No. 56-36991 describes an evaporative concentrator that uses a heat pump to evaporate raw water at a pressure higher than atmospheric pressure and high temperature (105°C) and then condense it. , discloses a double column structure with a condensation chamber on the outside and a concentration chamber on the inside. However, since this equipment operates under high temperature and high pressure, it is necessary to install multiple heat exchangers to control the temperature of the stock solution to be evaporated and concentrated before and after concentration, making the structure complex. There are drawbacks. In addition, Japanese Patent Publication No. 57-28281 describes an evaporative concentrator that uses a heat pump to evaporate raw water under reduced pressure and then condense it. They are provided as a body, each communicates with each other, and there is a pressure reducing means (vacuum pump)
discloses a configuration for reducing pressure in a condenser and concentrator. Further, German Patent DE3404248A1 describes an evaporative concentration device that uses a heat pump to evaporate raw water under reduced pressure and then condense it. In the drawing attached to the same specification, a condenser and a concentrator are provided in parallel, the upper parts of each are in communication, and a pressure reducing means (vacuum pump) is used to
A configuration is disclosed in which the condenser and concentrator are under reduced pressure. In addition, the heat pump is installed in the liquid,
The sides of the condenser and concentrator are closed configurations. However, in Japanese Patent Publication No. 57-28281 and German Patent DE3404248A1, there is a description of evaporation concentration under reduced pressure, but since the condenser and concentrator are installed separately or in parallel,
Similar to the technique described in Japanese Patent Application Laid-Open No. 63-151301, there are problems in that it takes up a lot of space and the device becomes large, which is not desirable. [Object of the Invention] Therefore, an object of the present invention is to provide an evaporative concentration device which has a simple and compact structure and has improved concentration efficiency, and which also reduces odor when the waste liquid is photographic processing waste liquid. An object of the present invention is to provide an evaporation concentration device that can also suppress the occurrence of. [Means for solving the problem] This objective is achieved by any one of the following means (a), (b), (c), and (d). (a) comprising a pressurizing section that pressurizes a heat medium, a heating section that utilizes heat radiation of the heat medium, an expansion section that expands the heat medium, and a cooling section that utilizes heat absorption of the heat medium, and , the heat medium is the pressurizing section,
a heat pump that sequentially circulates the heating section, the expansion section, and the cooling section in a closed state; an evaporation column for concentrating waste liquid; and an evaporation column that communicates with the evaporation column above and is disposed concentrically inside or outside the evaporation column, and that utilizes the cooling section to collect the vapor evaporated in the evaporation column. a condensation column that cools and condenses the water; and an ejector that reduces the pressure in the condensation column and recovers water condensed in the condensation column in order to reduce the pressure in the evaporation column and the condensation column. The heating part or the cooling part of the outer column of the evaporation column or the condensation column is arranged in a spiral along the outer wall of the inner column. Evaporative concentration equipment. (b) The evaporation concentration device according to item a, wherein the evaporation column is disposed inside and the condensation column is disposed outside. (c) Item a or b, characterized in that the ejector recovers the water condensed from the condensation column and reduces the pressure in the condensation column and the evaporation column from the bottom of the condensation column.
Evaporative concentrator as described in section. (d) The evaporation concentration device according to item a, b, or c, wherein the surface area of the cooling part is larger than the surface area of the heating part. [Example] An example of the evaporation concentration apparatus of the present invention will be described using the schematic diagram of FIG. For example, a photographic processing waste liquid is injected and stored in an evaporation column 1 that can withstand reduced pressure, and a condensation column 1A is provided inside the column 1, which is almost concentric with the column 1. Both columns are connected at the top, and an ejector 7 is commonly connected to both columns. I connected it and tried 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 this embodiment, evaporation is performed at a low temperature where gas generation is unlikely to occur. Next, in the column 1, a three-dimensionally arranged heating section, for example, a heating means 2, is provided.
The lower part thereof is immersed in the storage part 4 of the photographic processing waste liquid so as to heat the photographic processing waste liquid, and the upper part thereof protrudes from the storage part 4 of the photographic processing waste liquid and is in the air, and in this part, The photographic processing waste liquid is fed into the column 1 from the waste liquid storage tank (container) 31 using the liquid feeding means 3 using the electromagnetic valve 6A, and is subjected to heating evaporation under reduced pressure as well as heating evaporation during the spraying and dropping process. This process is repeated to achieve efficient and rapid concentration. The water evaporated here is stored in a spiral pipe-shaped cooling section, for example, a cooling means, which also forms a guide section for condensed water in the condensation column 1A, which communicates with a communication section provided at the upper part of the evaporation column 1. 8A and a water receiver 8C at the bottom of the column 1A,
This contributes to compactness and stabilization of the vacuum inside both columns. On the other hand, by repeating the above evaporative concentration, the components fixed at a high concentration are received and recovered in a container 12 connectable to the lower part of the evaporative condensation column 1. In this embodiment, the heating means 2 is arranged three-dimensionally in both the liquid and the air. It is effective in uniformly and efficiently performing low-temperature evaporation without gas generation. Furthermore, a cooling means 8A is provided in the condensation column 1A provided concentrically inside the evaporation column 1, so that water vapor entering through the communication portion is captured, cooled and condensed, and collected as water droplets. This has the effect of reducing the great load placed on the ejector 7 to maintain a specified reduced pressure state, which is caused by the generated steam disrupting the vacuum balance in both columns. That is, when the pressure in both columns increases due to generated steam, the pressure is immediately cooled and condensed to suppress the pressure increase. In this configuration, when the above-mentioned submerged part of the heating means 2 is set to the optimum temperature for the reduced-pressure evaporation, the above-mentioned part in the air that is integrated with the heating means 2 is also controlled at the same temperature, and due to the difference in heat transfer effect, the above-mentioned part in the air is controlled at the same temperature. The actual surface temperature of the portion located in the area becomes high, and if the photographic processing waste comes in contact with this, unpleasant gas may be generated due to rapid heating. Therefore, it is preferable to adjust the amount of the photographic processing waste that is supplied and sprayed from above. Further, in the present invention, a heat pump is used as the heating means 2 and the cooling means 8A. The water vapor comes in contact with the surface of the cooling means 8A, condenses, becomes water droplets, and is collected in the water recovery container 9 through the cooling means 8A. The surface temperature of the heating means 2 is preferably 100 DEG C. or less, and most preferably 20 DEG C. to 60 DEG C. in order to prevent the generation of odor gas in the case of photographic processing waste liquid. A heating part of a heat pump is used as the heating means 2, and a cooling part of a heat pump is used as the cooling means 8A and the cooling means 8B provided in the water recovery container 9. A charge pipe 25 for charging the condenser of the heat pump constituting the heating means 2, a capillary reach tube 26 disposed after the heating means 2 and serving as an expansion section, and a pressurization disposed on the outside of the cooling means 8A. a compressor 21 for compressing refrigerant and an air-cooled condenser 22 that air-cools and condenses the heat medium (refrigerant) that has been pressurized and compressed to a high temperature to an appropriate installation temperature;
The fan 24 and fan motor 23 are placed further outside the evaporation column 1. However, the space occupied by these external members is not so large, and most of the installation area is occupied by both columns. The above-mentioned appropriate setting temperature is the temperature that suppresses the generation of odor gas and does not significantly reduce the evaporation concentration efficiency, and as mentioned above, this is a temperature of 60°C or less and 20°C.
The applicant has experimentally confirmed that the above settings are effective. Now, the heat medium (refrigerant) passes through the heating section of the heating means 2 and is connected from the capillary reach tube 26 to the cooling means 8B in the water recovery container 9, and its extension is the cooling means 8A, that is, the condensation column 1A. The refrigerant passes through a pipe connected to the refrigerant evaporator and returns to the compressor 21 outside both columns, and circulates in a closed state. The cold water in the water recovery container 9 is connected to the ejector 7 by a water circulation pump (P-2) 33, and the water drawn through the pipe 34 from the condensate recovery port 8C of the condensation column 1A is transferred to the water recovery container 9. At the same time, the pressure inside both columns is reduced at the same time. 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 left at the exhaust port 3.
Since the air is exhausted from 6A, odor is completely prevented. The amount and timing of replenishment of waste liquid into the evaporation column 1 is determined based on information detected by a level sensor (LC) 64. In this embodiment, the evaporation column 1 and the condensation column 1A are not provided separately but are stacked almost concentrically.
Since it is made heavier, it does not take up much space, making it possible to make the device considerably smaller. This has made it possible to perform online waste liquid treatment even in small-scale laboratories without requiring much additional space. In this example, the outer side is the evaporation column 1 and the inner side is the condensation column 1A.
As shown in FIGS. 4 and 5, it is also possible to use an evaporation column on the inside and a condensation column on the outside. Figure 5a is a front cross-sectional view of such an embodiment, Figure 5b is a top view thereof, and Figure 5c is the same as Figure 5a.
It is a XX sectional view of. As shown in Figure 5b, the installation surface has a very small area of 500mm x 300mm in width L and length m, respectively, and the height h is 950mm as shown in Figure 5a.
It has a very compact and small structure. And the cooling part (refrigerant pipe) of condensation column 1A
8A is arranged outside the heating section (refrigerant pipe) 2 of the evaporation column 1, and the surface area of the refrigerant pipe 8A is set larger than that of the refrigerant pipe 2. This results in faster formation of condensate water.
The efficiency of pressure reduction is also good, and the phenomenon that the amount of pressure reduction decreases due to evaporated steam and the vapor pressure increases during evaporation and concentration is eliminated, which is preferable. Then, the surface area of the refrigerant pipe in the cooling section of the condensing column 1A and the surface area of the refrigerant pipe in the heating section of the evaporation column 1 are set in the dimensional ratio as shown in the following table, and the evaporation concentration efficiency is extremely improved as shown in the table. It was very successful.

[Table] By the way, in the comparison, the refrigerant pipes for evaporation concentration and cooling condensation are made to have almost the same dimensions and the same surface area, and instead of using double columns, the former is at the bottom and the latter is at the top, so that the refrigerant pipes are almost concentric. It is a storied structure. In the table above, the unit of outer diameter is mm. Fig. 3 shows a case in which the refrigerant pipe in the portion above the liquid level of the heating section by a heat pump is wound twice, and Fig. 4 shows a case in which all heating refrigerant pipes are wound twice. However, it is necessary to ensure that this does not increase the surface area of the pipe;
The diameter of the pipe was reduced to improve the efficiency of evaporation and concentration. Although not shown, both columns are concentrically arranged in a two-story structure, with the first floor serving as an evaporation column and the second floor serving as a condensation column. This also makes it possible to minimize the occupied area. However, there are cases where it is not desirable to place the evaporation concentration device too high above the top, and in this case, it is better to have a double structure as in some of the above-mentioned embodiments. [Effects of the Invention] According to the invention described in claim 1, since the evaporation column and the condensation column are arranged concentrically, that is, the structure is a double column, a very compact device can be obtained. Can be provided. In addition, since the evaporation column and the condensation column are depressurized by the ejector and evaporated and concentrated under reduced pressure, the operating temperature of the entire system (device) is low, and the structure is simple and can be made compact. Furthermore, by combining the structure of performing evaporation concentration under reduced pressure and the double column structure of an evaporation column and a condensation column, the vapor evaporated in the evaporation column immediately moves to the condensation column and is condensed in the condensation column. Therefore, it is possible to reduce the pressure loss accompanying the flow of steam and keep the temperature of the heating section of the heat pump low, thereby increasing the coefficient of performance of the heat pump and improving the concentration efficiency. Furthermore, by arranging the heating section or cooling section of the outer column in a spiral manner along the outer wall of the inner column, the required surface area of the heating section or cooling section can be reduced. can be easily secured, and the evaporation concentration device itself can be made compact. Furthermore, an ejector is used as a means to reduce the pressure in the evaporation column and condensation column, and this ejector not only reduces the pressure but also recovers condensed water, allowing continuous operation and cooling the condensation column. This has the effect of making it possible to constantly bring the parts into contact with steam (vapor evaporated in the evaporation column). Next, according to the second aspect of the invention, since the evaporation column is disposed inside the condensation column, the liquid can be efficiently evaporated in the evaporation column with a small volume, while the vapor can be efficiently evaporated in the condensation column with a large volume. It can be condensed, and a compact device can perform efficient heat exchange. Next, according to the invention described in claim 3, the recovery of condensed water from the condensation column and the pressure reduction in the condensation column and the evaporation column are continuously carried out from the bottom of the condensation column by an ejector. Not only is it possible to operate, but the water condensed in the condensation column can be quickly recovered, and the cooling section in the condensation column can be kept in constant contact with the steam, reducing the contact area between the cooling section and the steam. This has the effect of improving the production efficiency and condensation efficiency of condensed water. Next, according to the invention set forth in claim 4, the surface area of the cooling part of the condensation column is made larger than the surface area of the heating part of the evaporation column, so that it is possible to prevent condensation from occurring in the vapor, such as when concentrating photographic processing waste liquid. Even in the presence of condensed gas, the production of condensed water can be prevented from being impaired by non-condensable gas (improvement of condensation efficiency), and as a result, an appropriate amount of condensed water is produced, and the condensed water Since the non-condensable gas is re-adsorbed, an effect can be obtained in that the non-condensable gas can be discharged from the system together with the condensed water by the ejector.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram of an evaporative concentration apparatus for photographic processing waste liquid according to the present invention, and FIGS. 2, 3, and 4 are schematic sectional views of other embodiments of an evaporation column and a condensation column. , FIG. 5a is a front sectional view of one embodiment of the present invention, FIG. 5b is a top view thereof, and FIG. 5c is a sectional view taken along line XX in FIG. 5a. 1... Evaporation column, 1A... Condensation column, 2...
...Heating means, 6A...Solenoid valve, 8A, 8B...
...Cooling means, 21... Compressor, 22...
Air-cooled condenser, 23...fan motor, 24...fan.

Claims (1)

[Scope of Claims] 1. A pressurizing section that pressurizes a heat medium, a heating section that uses heat radiation of the heat medium, an expansion section that expands the heat medium, and a cooling section that uses heat absorption of the heat medium. a heat pump comprising: a heat pump in which the heat medium sequentially circulates through the pressurizing section, the heating section, the expansion section, and the cooling section in a closed state; an evaporation column that concentrates the waste liquid by heating and evaporating water in the waste liquid; an evaporation column that communicates with the evaporation column above and is disposed concentrically inside or outside the evaporation column; a condensation column that uses the cooling section to cool and condense the vapor evaporated in the evaporation column; an ejector for recovering water condensed in the column, and the heating part or the cooling part of the column disposed on the outside of the evaporation column or the condensation column is connected to the ejector of the column disposed on the inside. An evaporation concentration device characterized by being arranged spirally along an outer wall. 2. Claim 1, wherein the evaporation column is disposed on the inside, and the condensation column is disposed on the outside.
The described evaporative concentrator. 3. The evaporative concentration according to claim 1 or 2, wherein the ejector collects the water condensed from the condensation column and reduces the pressure in the condensation column and the evaporation column from the bottom of the condensation column. Device. 4. The evaporation concentration device according to claim 1, 2 or 3, wherein the surface area of the cooling section is larger than the surface area of the heating section.