Simplest developing solution

RalphLambrecht

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quiver

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Got an idea here for the disposal issue. The core of the problem is to not be so antisocial that you just pour your used chemicals on the ground. So the other solution to this problem would be to convert a liquid waste to a solid waste. You'll need either oil dry or kitty litter. Some steel wool for converting the ionic silver in your used fixer to a non-ionic form would be a good idea as well. Just pour your used and treated chemicals into the kitty litter then dispose of it in your trash. Space may be a bigger issue with this solution, but it's the only one that I can think of that doesn't involve polluting the places that you visit.
 

snusmumriken

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Good idea, but it doesn't seem problem-free to me. There are environmental concerns around at least some types of kitty litter; and sending chemical-soaked kitty litter to landfill would surely concentrate any pollution issue compared with dispersed disposal?

I agree that it is stupid to dispose of chemicals into environments that would be sensitive to them, and in that respect ionic silver seems to be the number one issue, although none of us seems to have a clear idea of how much damage 300 ml of working strength fixer would do, or to what. Unless the OP can rapidly evaporate excess water, he is going to have to carry a tank of waste fixer (at least) around with him, even if he saves space on the fresh chemicals. Can't help concluding with an earlier contributor that a digital camera is the responsible answer for the OP's circumstances.
 

quiver

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Considering that the OP was set on using a Caffenol developer, I can't see the pollution issue from that in a landfill situation. Used fix that has had the silver converted to a non-ionic form should be of no concern. Considering the chemicals that are regularly discarded by a household I think the concentration issue in a landfill isn't an issue. I don't know anything about the environmental concerns involving kitty litter, unless you speak of the origin of the diatomaceous earth that most is made from.
 

snusmumriken

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Others in this thread felt that while the environmental harm might be relatively trivial, any dumping of waste chemicals into the environment is irresponsible. That would presumably apply as much in a landfill, where pollutants will be quite concentrated, as to a lone photographer camping in an environmentally sensitive area. Ideally, I guess, everything would be rendered 'harmless' before disposal, but I suspect 'harmless' would turn out to be a relative term if we looked into it. For instance, the efficiency of silver recapture presumably has a practical limit. I suspect none of us really knows how much environmental damage our photographic waste is capable of causing without treatment or dilution. I would very much like to know. If anyone has a pdf of the Kodak report that dealt with these matters, I'd be very grateful to see it.

Yes, I was thinking of concerns about the 'mining' of diatomaceous earth, and the search for more sustainable plant-based substitutes for kitty litter. I hasten to add that I know nothing about these issues, only that the questions have been raised.
 

BrianShaw

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snusmumriken

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That's really helpful, thanks! I think there is another one yet from 1998 titled "Sources of Silver in Photographic Processing Facilities" that details how much silver could be entering your darkroom. I realise there's a rough figure in the first leaflet you have linked for the amount that might be leaving the darkroom in spent fixer. I am looking at ecotoxicity publications, and would also like to know how efficient silver recovery is. This is wandering well beyond our OP's question, though, so I'll start another thread when I have got somewhere.
 

John Wiegerink

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Also, landfills are not the same as they were 50 years ago. They are now lined with very heavy mil liners to prevent seepage in to ground water tables and streams. I'm not saying this is a perfect solution or to not take all precautions, but at least it's not like walking out the back door and dumping your chemicals. The newer landfills are pretty well regulated now and sure seem a lot better than putting all the waste, good and bad, on a barge and dumping them into the ocean. Also, many cities and county municipalities have hazardous waste drop off sites. Don't ask me where it goes from there as I don't know for sure. Maybe a high-temp incinerator? I have a soft spot for Xtol, but do use Pyrocat-HDC from time to time. Shame on me. Oh well at least I don't use it 100% of the time. JohnW
 

Mr Bill

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snusmumriken said:
I am looking at ecotoxicity publications, and would also like to know how efficient silver recovery is.
Click to expand...

The whole topic can get much deeper than you would probably imagine. There have been a number of silver recovery methods over the years, each with their own strengths and weaknesses. But these have to be part of a process "system."

For the most part, photo processing effluent is ruled more by regulatory bodies than by actual "ecotoxicity" effects (whatever that really is).

As a real brief introduction, the main concerns with common photographic effluent are mainly the "oxygen demand" (see either COD or BOD), and silver content. Now, if you dumped "enough" chemicals with a high oxygen demand into a stream, this is detrimental (it robs the aquatic organisms of oxygen). But if you dump the same thing into a sewage treatment plant, well, this is one of the main things that a treatment plant treats (human waste also has a high oxygen demand). Now, if you wanted to minimize your oxygen depleting waste, what would/could you do? Well, number one, you would reduce the total amount of chemical waste by using "replenishment" for everything, and in the case of fixer you would use multi-stage counter-current flow replenishment systems. By doing this you could reduce chemical waste by probably a factor of 5 or 10 times over the single-use processors. So the design of the "process" can have a major effect on the "ecotoxicity," again, whatever that really is.

With respect to silver-bearing waste, conventional internet lore is that this is toxic to micro organisms (as is ionic silver, such as dissolved silver nitrate). But photographic silver, in tests for "acute toxicity" in the environment, so to speak, is found to be relatively benign compared to ionic silver. In the US, at least, it is possible for a photo finisher to get a special sewering permit from local municipalities to handle their effluent. Yet it is subject to the same regulatory standards that were probably intended for ionic silver. And some of these standards are so low as to be crazy, in my view.
 

Donald Qualls

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Mr Bill said:
number one, you would reduce the total amount of chemical waste by using "replenishment" for everything, and in the case of fixer you would use multi-stage counter-current flow replenishment systems.
Click to expand...

Of course, this is effectively impossible for a limited space, "van life" film processing setup.

I'm still in favor of a monobath, reused to exhaustion, then hauled out in the same bottle used to haul it in and disposed of on a town stop. No dumping anything more polluting than wash water, and an Ilford wash will use just about a quart for a single roll of 35mm.
 
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