CA2105416A1 - Method and apparatus for silver recovery from photographic processing solutions - Google Patents
Method and apparatus for silver recovery from photographic processing solutionsInfo
- Publication number
- CA2105416A1 CA2105416A1 CA 2105416 CA2105416A CA2105416A1 CA 2105416 A1 CA2105416 A1 CA 2105416A1 CA 2105416 CA2105416 CA 2105416 CA 2105416 A CA2105416 A CA 2105416A CA 2105416 A1 CA2105416 A1 CA 2105416A1
- Authority
- CA
- Canada
- Prior art keywords
- effluent
- tank
- solution
- precipitate
- trimercapto
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Abandoned
Links
- BQCADISMDOOEFD-UHFFFAOYSA-N Silver Chemical compound [Ag] BQCADISMDOOEFD-UHFFFAOYSA-N 0.000 title claims abstract description 29
- 229910052709 silver Inorganic materials 0.000 title claims abstract description 28
- 239000004332 silver Substances 0.000 title claims abstract description 28
- 238000000034 method Methods 0.000 title claims abstract description 12
- 238000011084 recovery Methods 0.000 title abstract description 9
- 238000006243 chemical reaction Methods 0.000 claims abstract description 13
- 229940100890 silver compound Drugs 0.000 claims abstract description 8
- 150000003379 silver compounds Chemical class 0.000 claims abstract description 8
- 150000003839 salts Chemical class 0.000 claims abstract description 7
- 238000011282 treatment Methods 0.000 claims abstract description 7
- 238000001556 precipitation Methods 0.000 claims abstract description 5
- 239000007791 liquid phase Substances 0.000 claims description 9
- 239000002244 precipitate Substances 0.000 claims description 6
- 230000003750 conditioning effect Effects 0.000 claims description 5
- 239000007788 liquid Substances 0.000 claims description 5
- 239000007790 solid phase Substances 0.000 claims description 5
- 238000000926 separation method Methods 0.000 claims description 4
- 239000007787 solid Substances 0.000 claims description 3
- 230000001143 conditioned effect Effects 0.000 claims description 2
- 230000001376 precipitating effect Effects 0.000 claims description 2
- 239000006228 supernatant Substances 0.000 claims 1
- 239000002245 particle Substances 0.000 description 4
- 150000001875 compounds Chemical class 0.000 description 3
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 2
- 230000007613 environmental effect Effects 0.000 description 2
- 230000005484 gravity Effects 0.000 description 2
- GGCZERPQGJTIQP-UHFFFAOYSA-N sodium;9,10-dioxoanthracene-2-sulfonic acid Chemical compound [Na+].C1=CC=C2C(=O)C3=CC(S(=O)(=O)O)=CC=C3C(=O)C2=C1 GGCZERPQGJTIQP-UHFFFAOYSA-N 0.000 description 2
- 239000003381 stabilizer Substances 0.000 description 2
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- 244000228957 Ferula foetida Species 0.000 description 1
- 229910000831 Steel Inorganic materials 0.000 description 1
- 229910052783 alkali metal Inorganic materials 0.000 description 1
- -1 alkali metal salt Chemical class 0.000 description 1
- 239000007844 bleaching agent Substances 0.000 description 1
- 229910052742 iron Inorganic materials 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 230000003134 recirculating effect Effects 0.000 description 1
- 238000004062 sedimentation Methods 0.000 description 1
- 239000010959 steel Substances 0.000 description 1
- 230000001960 triggered effect Effects 0.000 description 1
- HRXKRNGNAMMEHJ-UHFFFAOYSA-K trisodium citrate Chemical compound [Na+].[Na+].[Na+].[O-]C(=O)CC(O)(CC([O-])=O)C([O-])=O HRXKRNGNAMMEHJ-UHFFFAOYSA-K 0.000 description 1
- SOBHUZYZLFQYFK-UHFFFAOYSA-K trisodium;hydroxy-[[phosphonatomethyl(phosphonomethyl)amino]methyl]phosphinate Chemical compound [Na+].[Na+].[Na+].OP(O)(=O)CN(CP(O)([O-])=O)CP([O-])([O-])=O SOBHUZYZLFQYFK-UHFFFAOYSA-K 0.000 description 1
- 239000002699 waste material Substances 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
- 239000003643 water by type Substances 0.000 description 1
- 210000002268 wool Anatomy 0.000 description 1
Classifications
-
- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- G03C—PHOTOSENSITIVE MATERIALS FOR PHOTOGRAPHIC PURPOSES; PHOTOGRAPHIC PROCESSES, e.g. CINE, X-RAY, COLOUR, STEREO-PHOTOGRAPHIC PROCESSES; AUXILIARY PROCESSES IN PHOTOGRAPHY
- G03C5/00—Photographic processes or agents therefor; Regeneration of such processing agents
- G03C5/26—Processes using silver-salt-containing photosensitive materials or agents therefor
- G03C5/395—Regeneration of photographic processing agents other than developers; Replenishers therefor
- G03C5/3952—Chemical, mechanical or thermal methods, e.g. oxidation, precipitation, centrifugation
-
- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- G03D—APPARATUS FOR PROCESSING EXPOSED PHOTOGRAPHIC MATERIALS; ACCESSORIES THEREFOR
- G03D3/00—Liquid processing apparatus involving immersion; Washing apparatus involving immersion
- G03D3/02—Details of liquid circulation
- G03D3/06—Liquid supply; Liquid circulation outside tanks
- G03D3/065—Liquid supply; Liquid circulation outside tanks replenishment or recovery apparatus
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Silver Salt Photography Or Processing Solution Therefor (AREA)
- Removal Of Specific Substances (AREA)
Abstract
ABSTRACT
A method and apparatus for treatment of photographic effluent solutions provides a tank (1) for holding a solution of trimercapto-s-triazine or its water-soluble salt, at least one effluent tank (2) for holding overflow from a post-development photographic processing solution, a reaction and precipitate-conditioning vessel (4), means for determining when the or each effluent tank is filled to a predetermined extent, means (3) for delivering the contents of an effluent tank and an appropriate amount of the trimercapto-s-triazine solution to the reaction and precipitate-conditioning vessel (4), and means for separating the insoluble silver compound from the treated solution (6,7,8) after precipitation of an insoluble silver compound. The invention permits efficient and automated silver recovery from a photographic effluent solution having a silver concentration of 2 ppm or below.
A method and apparatus for treatment of photographic effluent solutions provides a tank (1) for holding a solution of trimercapto-s-triazine or its water-soluble salt, at least one effluent tank (2) for holding overflow from a post-development photographic processing solution, a reaction and precipitate-conditioning vessel (4), means for determining when the or each effluent tank is filled to a predetermined extent, means (3) for delivering the contents of an effluent tank and an appropriate amount of the trimercapto-s-triazine solution to the reaction and precipitate-conditioning vessel (4), and means for separating the insoluble silver compound from the treated solution (6,7,8) after precipitation of an insoluble silver compound. The invention permits efficient and automated silver recovery from a photographic effluent solution having a silver concentration of 2 ppm or below.
Description
210~16 METHOD AND APPARATUS FOR SILVER RECOVEP.Y FRO~
PHOTOGRAPHIC PROCESSING SOLUTIONS
This invention relates to a method and apparatus for silver recovery from photographic processing solutions or effluent or overflow solutionq therefrom. ``
There are many ways in which silver has been recovered from photographic processing solutions and waste liquors. Some involve exchange of iron for silver using steel wool. Others involve an electrolytic step in which silver metal is recovered at the anode.
In copending PCT application EP92/01583 there is described a method and apparatus for treating effluent produced by a photographic processing apparatus which, by a multistage process, produces a liquid and a solid which can be disposed of directly to drain or landfill respectively without infringing any current environmental disposal regulations. The specification does not, however, deal with the question of silver recovery.
Clearly the recovery of silver is worthwhile from an environmental standpoint alone but, in addition, the cost of recovering silver is usually outweighed by the value of the silver ~o recovered.
The present invention has as its object a machine which is able to recover silver from photographic processing or effluent solutions efficiently and automatically without operator intervention.
According to the present invention there is provided an apparatus for the treatment of photographic effluent solutions comprising a tank for holding a solution of trimercapto-s-triazine or a water-soluble salt thereof; at least one effluent tank for holding overflow from a post-development photographic processing solution; a reaction and precipitate-conditioning vessel; means for determining when the or , .... .. ~.. ...... . , .. ". . ~ . . ., . ; .. -.. ~.. . . . - . ,.,. . .- . , -.
r~ 2 210 ~ q 1 6 each effluent tank is filled to a predetermined extent means for delivering the contents of an effluent tank and an appropriate amount of the trimercapto-~-triazine solution to the reaction and precipitate-conditioning vessel; and means for separating the insoluble ~ilver compound from the treated solution after precipitation of an insoluble silver compound.
The post development processing solutions may, for example, be bleach and/or bleach-fix and/or fixer and/or stabilizer solutions and/or wash waters.
The present invention also provides a method of treating silver-containing photographic effluent solutions contained in an effluent tank which compri~es reacting a batch of the effluent solution with an appropriate amount of a solution of trimercapto-~-triazine or a water-soluble salt thereof, precipitating an insoluble silver compound thereby, allowing the precipitate to be conditioned by holding it for sufficient time in the conditioning tank and separating the solid and liquid phases in an apparatus as described above. The process is preferably triggered in response to a signal from an effluent tank level determining means indicating that the next batch of predetermined volume is ready to be processed.
In a preferred embodiment, the apparatus is controlled by a microprocessor.
The advantage of the present invention is that it allows easy automated silver recovery at a level of silver of 2ppm silver or below in the solution, little operator involvement and minimal power consumption.
The trimercapto-s-triazine compound may be an alkali metal salt thereof, for example the trisodium or tripotassium salt. As used below the term trimercapto-s-triazine will include both the compound itself and salts thereof. These compounds are available from DEGUSSA. The amount of trimercapto-s-triazine used will be based on the volume of solution to be treated -and its origin (i.e. whether from a film or paper process) as its silver content will be known with sufficient accuracy. In this case it is convenient to have two effluent tanks, one from a film processor and the other from a paper processor. A third tank containing overflow from the stabilizer can also be used. In one embodiment of the present invention known volumes from each of the effluent tankq may be combined for silver recovery.
Alternatively, instead of calculating the amount of silver present, the silver content of the effluent can be determined by known means, for example by measuring its pAg with an suitable electrode.
When using the trisodium salt of trimercapto-s-triazine ~TMT) from 1 to 3 moles can be added per 3 moles of silver. A preferred amount of TMT is 1.25 to 1.5 moles per 3 moles of silver.
In one embodiment of the present invention the reaction and precipitate-conditioning vessel may be replaced by separate reaction and precipitate-conditioning vessels. This allows each vessel to be optimized for its purpose. The vessel where the precipitation takes place is preferably fitted with a stirrer.
In a combined vessel the solutions are run into it to react and precipitate the insoluble silver salt and remain there for the silver salt to settle out. It is believed that during this conditioning period the finer particles of the precipitate dissolve and reprecipitate onto the larger particles thus reducing the number of small particles present. Clearly this aids separation of the solid and liquid phases. In the case of separate vessels, each can be optimized for its own function.
- - . . . . .
- - ` ' ' ~ :: . . . '- ..
210~416 The effluent tank(s) are preferably fed from a larger collection tank fed by overflow from the processing tanks. This allow~ the effluent tank(s) to be filled with a fixed volume of liquid as soon as they are emptied. It i8 preferred in such a case that means are provided for transferring a predetermined volume of effluent from the collection tank to an effluent tank which iq sufficient to substantially completely fill it. The effluent tank~s) will then be able to deliver the next batch of effluent of known volume as soon as the reaction vessel is free to process it. The collection tank may have a vclume of 15-20 liters, while the smaller tanks may have a volume of 0.2 to 3 liters, preferably 0.5 to 1.5 liters.
After a predetermined number of treatments the contents of the sedimentation tank is transferred to a filter to separate the liquid and solid phases prior to disposal and silver recovery. The liquid phase may optionally undergo further treatment or be reused in a processing solution.
If the liquid phase is to be processed further it could be passed to an apparatus as described in PCT
Specification EP92/01583 where it could be combined with developer effluent.
Although the apparatus and method are de~cribed below with particular reference to minilabs, the present apparatus may also be designed on a larger scale to deal with effluent from a photofini~hing laboratory.
The invention will now be described with reference to the accompanying drawings in which:
Figures 1 and 2 are diagrammatic representations of apparatus according to the present invention.
In Figure 1 the holding tank trimercapto-s-triazine solution (1) and effluent tanks (2) are arranged to deliver their contents flowing under gravity via valves (3) into combined reaction and precipitate-conditioning vessel (4) in which a stirrer (5) is provided. Typically in the minilab environment, the effluent tanks will contain overflow from the film fixer, paper fixer and wa~h water. When one of the tank~ ~2) i~ filled to a predetermined level its contentq together with the appropriate amount of trimercapto-s-triazine ~olution from tank (1) i8 alqo added. Each tank (2) can be fed from a different source whoqe average silver content iQ known, hence the amount of trimercapto-s-triazine can be calculated.
Tank (4) can have a volume in the range 10-20 liters, preferably 12-15 liters. When ready the precipitate and liquid are pumped by pump (6) into a filter bag (7) through which the liquid will paQs and exit via outlet (8).
When attached to a minilab proce~sing 50 customer order~ per day, then a total of 12 liters of ~ilver-bearing Qolution will need to be treated. The residence time in tank (4) will be approaching 2 days.
The reQidence time can vary from 1-5 hours, preferably 2-3 hours but has no upper limit.
In normal operation, after a predetermined number of treatment cycles, the conditioning tank (4) contents will be separated. When microprocessor controlled the calculation is made b~ the -qystem software and, when required, the pump (6) will be activated thus transferring the contents of tank (4) into the filter bag (7). The preferred filter bags have mesh apertures 30 of 0.2 to 2 mm, preferably 0.5 to 1.0 mm. The separation may take place under the influence of gravity over a period of several hour~. After several cycles the filter bag will be changed and the separated solid sent for silver recovery by a refiner.
The apparatus will remove silver leaving no more than 2 ppm silver in the liquid phase.
210~4~6 In Figure 2 tanks (1) and (2) carry out the same functions as above, as do pump ~6), filter bag (7) and outlet (8). A separate reaction vessel ~9) is provided together with a recirculating pump (10) which is active during the precipitation step. The fully reacted mixture will then pass to conditioning tank (4) so that the small particle~ will dissolve and reprecipitate on the larger grains. Separation of the solid and liquid phases will be carried out as described above in relation to Figure 1.
. ~,.. , .. , .. , :, .:,,.,., . . . :, , , . . .,, ,- .. , .: .: ." . .. - . . ..
PHOTOGRAPHIC PROCESSING SOLUTIONS
This invention relates to a method and apparatus for silver recovery from photographic processing solutions or effluent or overflow solutionq therefrom. ``
There are many ways in which silver has been recovered from photographic processing solutions and waste liquors. Some involve exchange of iron for silver using steel wool. Others involve an electrolytic step in which silver metal is recovered at the anode.
In copending PCT application EP92/01583 there is described a method and apparatus for treating effluent produced by a photographic processing apparatus which, by a multistage process, produces a liquid and a solid which can be disposed of directly to drain or landfill respectively without infringing any current environmental disposal regulations. The specification does not, however, deal with the question of silver recovery.
Clearly the recovery of silver is worthwhile from an environmental standpoint alone but, in addition, the cost of recovering silver is usually outweighed by the value of the silver ~o recovered.
The present invention has as its object a machine which is able to recover silver from photographic processing or effluent solutions efficiently and automatically without operator intervention.
According to the present invention there is provided an apparatus for the treatment of photographic effluent solutions comprising a tank for holding a solution of trimercapto-s-triazine or a water-soluble salt thereof; at least one effluent tank for holding overflow from a post-development photographic processing solution; a reaction and precipitate-conditioning vessel; means for determining when the or , .... .. ~.. ...... . , .. ". . ~ . . ., . ; .. -.. ~.. . . . - . ,.,. . .- . , -.
r~ 2 210 ~ q 1 6 each effluent tank is filled to a predetermined extent means for delivering the contents of an effluent tank and an appropriate amount of the trimercapto-~-triazine solution to the reaction and precipitate-conditioning vessel; and means for separating the insoluble ~ilver compound from the treated solution after precipitation of an insoluble silver compound.
The post development processing solutions may, for example, be bleach and/or bleach-fix and/or fixer and/or stabilizer solutions and/or wash waters.
The present invention also provides a method of treating silver-containing photographic effluent solutions contained in an effluent tank which compri~es reacting a batch of the effluent solution with an appropriate amount of a solution of trimercapto-~-triazine or a water-soluble salt thereof, precipitating an insoluble silver compound thereby, allowing the precipitate to be conditioned by holding it for sufficient time in the conditioning tank and separating the solid and liquid phases in an apparatus as described above. The process is preferably triggered in response to a signal from an effluent tank level determining means indicating that the next batch of predetermined volume is ready to be processed.
In a preferred embodiment, the apparatus is controlled by a microprocessor.
The advantage of the present invention is that it allows easy automated silver recovery at a level of silver of 2ppm silver or below in the solution, little operator involvement and minimal power consumption.
The trimercapto-s-triazine compound may be an alkali metal salt thereof, for example the trisodium or tripotassium salt. As used below the term trimercapto-s-triazine will include both the compound itself and salts thereof. These compounds are available from DEGUSSA. The amount of trimercapto-s-triazine used will be based on the volume of solution to be treated -and its origin (i.e. whether from a film or paper process) as its silver content will be known with sufficient accuracy. In this case it is convenient to have two effluent tanks, one from a film processor and the other from a paper processor. A third tank containing overflow from the stabilizer can also be used. In one embodiment of the present invention known volumes from each of the effluent tankq may be combined for silver recovery.
Alternatively, instead of calculating the amount of silver present, the silver content of the effluent can be determined by known means, for example by measuring its pAg with an suitable electrode.
When using the trisodium salt of trimercapto-s-triazine ~TMT) from 1 to 3 moles can be added per 3 moles of silver. A preferred amount of TMT is 1.25 to 1.5 moles per 3 moles of silver.
In one embodiment of the present invention the reaction and precipitate-conditioning vessel may be replaced by separate reaction and precipitate-conditioning vessels. This allows each vessel to be optimized for its purpose. The vessel where the precipitation takes place is preferably fitted with a stirrer.
In a combined vessel the solutions are run into it to react and precipitate the insoluble silver salt and remain there for the silver salt to settle out. It is believed that during this conditioning period the finer particles of the precipitate dissolve and reprecipitate onto the larger particles thus reducing the number of small particles present. Clearly this aids separation of the solid and liquid phases. In the case of separate vessels, each can be optimized for its own function.
- - . . . . .
- - ` ' ' ~ :: . . . '- ..
210~416 The effluent tank(s) are preferably fed from a larger collection tank fed by overflow from the processing tanks. This allow~ the effluent tank(s) to be filled with a fixed volume of liquid as soon as they are emptied. It i8 preferred in such a case that means are provided for transferring a predetermined volume of effluent from the collection tank to an effluent tank which iq sufficient to substantially completely fill it. The effluent tank~s) will then be able to deliver the next batch of effluent of known volume as soon as the reaction vessel is free to process it. The collection tank may have a vclume of 15-20 liters, while the smaller tanks may have a volume of 0.2 to 3 liters, preferably 0.5 to 1.5 liters.
After a predetermined number of treatments the contents of the sedimentation tank is transferred to a filter to separate the liquid and solid phases prior to disposal and silver recovery. The liquid phase may optionally undergo further treatment or be reused in a processing solution.
If the liquid phase is to be processed further it could be passed to an apparatus as described in PCT
Specification EP92/01583 where it could be combined with developer effluent.
Although the apparatus and method are de~cribed below with particular reference to minilabs, the present apparatus may also be designed on a larger scale to deal with effluent from a photofini~hing laboratory.
The invention will now be described with reference to the accompanying drawings in which:
Figures 1 and 2 are diagrammatic representations of apparatus according to the present invention.
In Figure 1 the holding tank trimercapto-s-triazine solution (1) and effluent tanks (2) are arranged to deliver their contents flowing under gravity via valves (3) into combined reaction and precipitate-conditioning vessel (4) in which a stirrer (5) is provided. Typically in the minilab environment, the effluent tanks will contain overflow from the film fixer, paper fixer and wa~h water. When one of the tank~ ~2) i~ filled to a predetermined level its contentq together with the appropriate amount of trimercapto-s-triazine ~olution from tank (1) i8 alqo added. Each tank (2) can be fed from a different source whoqe average silver content iQ known, hence the amount of trimercapto-s-triazine can be calculated.
Tank (4) can have a volume in the range 10-20 liters, preferably 12-15 liters. When ready the precipitate and liquid are pumped by pump (6) into a filter bag (7) through which the liquid will paQs and exit via outlet (8).
When attached to a minilab proce~sing 50 customer order~ per day, then a total of 12 liters of ~ilver-bearing Qolution will need to be treated. The residence time in tank (4) will be approaching 2 days.
The reQidence time can vary from 1-5 hours, preferably 2-3 hours but has no upper limit.
In normal operation, after a predetermined number of treatment cycles, the conditioning tank (4) contents will be separated. When microprocessor controlled the calculation is made b~ the -qystem software and, when required, the pump (6) will be activated thus transferring the contents of tank (4) into the filter bag (7). The preferred filter bags have mesh apertures 30 of 0.2 to 2 mm, preferably 0.5 to 1.0 mm. The separation may take place under the influence of gravity over a period of several hour~. After several cycles the filter bag will be changed and the separated solid sent for silver recovery by a refiner.
The apparatus will remove silver leaving no more than 2 ppm silver in the liquid phase.
210~4~6 In Figure 2 tanks (1) and (2) carry out the same functions as above, as do pump ~6), filter bag (7) and outlet (8). A separate reaction vessel ~9) is provided together with a recirculating pump (10) which is active during the precipitation step. The fully reacted mixture will then pass to conditioning tank (4) so that the small particle~ will dissolve and reprecipitate on the larger grains. Separation of the solid and liquid phases will be carried out as described above in relation to Figure 1.
. ~,.. , .. , .. , :, .:,,.,., . . . :, , , . . .,, ,- .. , .: .: ." . .. - . . ..
Claims (10)
1. An apparatus for the treatment of photographic effluent solutions comprising a tank (1) for holding a solution of trimercapto-s-triazine or a water-soluble salt thereof; at least one effluent tank (2) for holding overflow from a post-development photographic processing solution; a reaction and precipitate-conditioning vessel (4); means for determining when the or each effluent tank is filled to a predetermined extent; means (3) for delivering the contents of an effluent tank and an appropriate amount of the trimercapto-s-triazine solution to the reaction and precipitate-conditioning vessel (4); and means for separating the insoluble silver compound from the treated solution (6,7,8) after precipitation of an insoluble silver compound.
2. An apparatus as claimed in claim 1 in which the means for separating the insoluble silver compound from the treated solution is a filter.
3. An apparatus as claimed in claim 2 in which the reaction and precipitate-conditioning vessel (4) is replaced by separate reaction and precipitate-conditioning vessels (9,4).
4. An apparatus as claimed in claim 3 in which the precipitate is allowed to settle in the precipitate-conditioning vessel (4) and the separation is achieved by removing the supernatant liquid from the settled solid.
5. An apparatus as claimed in claim 4 in which the effluent tank(s) are fed from a larger collection tank fed by overflow from the processing tanks.
6. An apparatus as claimed in claim 5 in which means are provided for transferring a predetermined volume of effluent from the collection tank to an effluent tank which is sufficient to substantially completely fill said effluent tank.
7. An apparatus as claimed in claim 6 which is controlled by a microprocessor.
8. An apparatus as claimed in claim 7 in which the filter has an aperture size of from 0.2 to 2 mm.
9. An apparatus as claimed in any of claims 1 to 8 in which the separated liquid phase receives further treatment prior to disposal or is recycled for use in a photographic processing solution.
10. A method for treating silver-containing photographic effluent solutions contained in a effluent tank (2) which comprises reacting a batch of the effluent solution with an appropriate amount of a solution of trimercapto-s-triazine or a water-soluble salt thereof, precipitating an insoluble silver compound thereby, allowing the precipitate to be conditioned by holding it for sufficient time in the conditioning tank (4) and separating the solid and liquid phases in an apparatus as claimed in any of claims 1 to 11.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB9219675.7 | 1992-09-17 | ||
| GB929219675A GB9219675D0 (en) | 1992-09-17 | 1992-09-17 | Method and apparatus for silver recovery from photographic processing solutions |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA2105416A1 true CA2105416A1 (en) | 1994-03-18 |
Family
ID=10722070
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA 2105416 Abandoned CA2105416A1 (en) | 1992-09-17 | 1993-09-02 | Method and apparatus for silver recovery from photographic processing solutions |
Country Status (4)
| Country | Link |
|---|---|
| EP (1) | EP0596549A1 (en) |
| JP (1) | JPH06190377A (en) |
| CA (1) | CA2105416A1 (en) |
| GB (1) | GB9219675D0 (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB9517903D0 (en) * | 1995-09-02 | 1995-11-01 | Kodak Ltd | Apparatus for separating effluent into solid and liquid phases |
| US5728295A (en) * | 1996-04-19 | 1998-03-17 | Fuji Hunt Photographic Chemicals, Inc. | Apparatus for removing metal ions and/or complexes containing metal ions from a solution |
Family Cites Families (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS516459B2 (en) * | 1971-08-18 | 1976-02-27 | ||
| GB1411985A (en) * | 1972-10-18 | 1975-10-29 | Ilford Ltd | Silver recovery process |
| CH655711A5 (en) * | 1982-10-20 | 1986-05-15 | Rehman Process Eng | Method for disposal arbeitsfluessigkeiten from the photo chemical industry. |
| JP2588781B2 (en) * | 1989-10-20 | 1997-03-12 | 富士写真フイルム株式会社 | How to replenish processing solution |
| GB9115799D0 (en) * | 1991-07-20 | 1991-09-04 | Kodak Ltd | Treatment of photographic effluent |
-
1992
- 1992-09-17 GB GB929219675A patent/GB9219675D0/en active Pending
-
1993
- 1993-09-02 CA CA 2105416 patent/CA2105416A1/en not_active Abandoned
- 1993-09-15 EP EP93202671A patent/EP0596549A1/en not_active Withdrawn
- 1993-09-16 JP JP23008993A patent/JPH06190377A/en active Pending
Also Published As
| Publication number | Publication date |
|---|---|
| JPH06190377A (en) | 1994-07-12 |
| EP0596549A1 (en) | 1994-05-11 |
| GB9219675D0 (en) | 1992-10-28 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US5288728A (en) | Process for recovering silver from photographic solutions | |
| JPH024661B2 (en) | ||
| EP0655419B1 (en) | Process for treating photographic waste water | |
| EP0596549A1 (en) | Method and apparatus for silver recovery from photographic processing solutions | |
| US4279644A (en) | Recovery of silver from photographic processor effluents | |
| EP0787689A2 (en) | Method of treating waste effluent | |
| EP0548106B1 (en) | Effluent treatment | |
| US5085836A (en) | Process for desilvering silver halide processing fluids | |
| EP0685763A1 (en) | Process for recycling photographic wash water | |
| US5622631A (en) | Process for reducing consumption of fresh water and energy costs used in a photofinishing operation | |
| Bober et al. | Treatment of photographic processing wastes | |
| EP0619272A1 (en) | Method for the purification of waste water containing silver | |
| JPS6347779B2 (en) | ||
| EP0761276B1 (en) | Apparatus for separating effluent into solid and liquid phases | |
| US5289223A (en) | Chemical recycler for photo processing machine | |
| PL165799B1 (en) | How to regenerate a photo fixer PL PL PL PL PL PL PL | |
| US6126840A (en) | Process for removing silver in the presence of iron from waste effluent | |
| EP0729066B1 (en) | Removal of tin from seasoned photographic color developers | |
| RU2101234C1 (en) | Method and installation for removing radionuclides form sea water-type low-salt solutions | |
| JP2676644B2 (en) | Method and device for silver recovery of photographic processing liquid | |
| US5884116A (en) | Photographic processing apparatus | |
| Bober et al. | 6.1 THE PHOTOGRAPHIC PROCESS | |
| Lorenzo | Ozone in the Photoprocessing Industry | |
| Wang et al. | Treatment of Photographic Processing Wastes | |
| Zarzycki | Application of Silver Recovery to the ES-38 Mobile Photographic Processing Laboratory. |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| EEER | Examination request | ||
| FZDE | Dead |