Silver Recovery

mklw1954 said:

Let's get a little perspective on silver recovery. Check out Kodak Publication J-210 "Sources of Silver in Photographic Processing Facilities". It provides an example of how much silver can be recovered by a lab. A lab processing 50 rolls per day, 6 days per week, i.e., 15,000 rolls per year can recover 280 troy oz. of silver per year. At $20 per oz. you could get $5,600 per year for that amount of silver, not including the cost of equipment and chemicals to recover it. But that's for a lab. I typically shoot and develop 60 rolls of film per year. So, proportionally, I could get $22 a year for the silver, not including the cost of recovering it. In other words, it's not worth considering.

On the environmental side, the amount (mass) of silver you dispose to the drain is so small that it's probably not detectable after dilution, perticularly if you are on a community sewer and sewage treatment plant system. Maybe a heavy home film/paper developer on a septic system would have a concern after many years.

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jnanian said:

kodak made a 180 degree turnaround from the publication that is usually quoted from where they say it is okay
to put the stuff down the drain. another publication from the same source ( kodak ) a few years later ( 1990s)
says do not put anything down the drain.

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AgX said:

Visit the water authorities at your county resp. independant city authority:

"Effluents/waste from photographic processes are considered as fluid waste and may not be dumped into the sewage system."

For non-commercial users there is the free hazardous-waste collecting service offered by cities and counties.
As commercial user you have inform.

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oldtimermetoo said:

Please don't forget the chemicals used in making printed circuit boards and probably in making other components, not to mention chemicals in the paint, etc, etc, etc........Regards

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Photo Engineer said:

Circuit boards are made with an etching solution similar to the E6 Bleach. So, this does apply in that case regarding dumping.

Lye drain cleaners and other types of solutions also alter pH drastically and thus fit in with some developers such as Rodinal and etc.

The list goes on.

PE

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marciofs said:

I think the concern is more about heavy metals.

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jnanian said:

hi PE

i agree, it might apply in general sense, but marcoifs was asking about photochemistry, not etching circuit boards or lye.

over the years whenever someone asks a question specific to photochemistry respondents go off on a tangent about household cleaners or other things else that
have nothing to do with the asked question/s ... and then respondents start moaning about how fascist the governments are for not allowing us to dump whatever we
want down the drain ... because it is their right as property owners to do whatever they want ( &c ) ... its not that i don't agree with you, i do but
from what i gather he is not using exotic bleaches, toners, or doing e6 / c41 processing but basic black and white ( maybe i am wrong ? )




hi marciofs

run of the mill black and white chemistry i don't believe has heavy metals. ( i might be wrong )
there is silver that ends up in the fixer, but over the years folks ( including me ! ) have referred to silver
as a heavy metal and were corrected ... maybe exotic toners have heavy metals in them ?
but from all reports, developer, stop bath, fixer, fixer remover and water don't have heavy metals in them ...

the silver is a bacteriacide / kills the beneficial bacteria in the sewer/septic system, and depending
on your location ( at least here in the usa ) local regulations may supersede federal / state regulations.
for example federal / state regulations might say 5parts per million silver is not OK to drain,
but local regulations might say 3 or 1 part per million because of various watershed issues &c ...

its best to find out where you live what the regulations are and proceed from there.
and often times towns have household waste recovery day where you can bring
a bucket of photo-waste and just leave it for the town/city &c to deal with ... like with cans of paint, or CFC lightbulbs &c.

you might be able to find a company that sells trickle tanks ( locally ) and put all your fixer and wash water through the tank which will exchange
iron ( usually ) for silver and the trickle tanks will get you pretty low .. not to "0" but somewhere between 1ish and 5 depending on how you use it
( and if you put it through a 2nd time it gets lower ) ... depending on the media and amount of media in the tank, they last anywhere from 200-800 gallons
and if you use some sort of pre-treatment ( like an electrolytic system ( like a silver magnet ) ) you will get more than double the gallons/lifespan.

good luck
john

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Photo Engineer said:

John, I guess I was too vague. Many cities or regions ban photochemicals being dumped, when in fact many household chemicals contain similar ingredients. Also, they ignore ingredients from industries other than photography. It seems that when there were a lot of photo labs "in the day", well, they were on the radar for government and the small uses are off the radar. So cleaning a drain with lye is legal but dumping Rodinal is not in some areas - it is photographic.

In reality, now, the use of photographic chemicals is so "rare" that it is tantamount to drain cleaning.

Now, I am the first to admit that there are other chemicals in photographic effluent, but consider how many people dump pills. So, a dump of old Tylenol and then cleaning your drain is the same as dumping an equivalent of developer. And "fixing" your pool in the summer and then backwashing can put as much hypo out there as processing and printing your film and then dumping the fixer.

PE

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Photo Engineer said:

John, I guess I was too vague. Many cities or regions ban photochemicals being dumped, when in fact many household chemicals contain similar ingredients. Also, they ignore ingredients from industries other than photography. It seems that when there were a lot of photo labs "in the day", well, they were on the radar for government and the small uses are off the radar. So cleaning a drain with lye is legal but dumping Rodinal is not in some areas - it is photographic.

In reality, now, the use of photographic chemicals is so "rare" that it is tantamount to drain cleaning.

Now, I am the first to admit that there are other chemicals in photographic effluent, but consider how many people dump pills. So, a dump of old Tylenol and then cleaning your drain is the same as dumping an equivalent of developer. And "fixing" your pool in the summer and then backwashing can put as much hypo out there as processing and printing your film and then dumping the fixer.

PE

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clipvietbao said:

The "cart it to a hazardous waste facility" solution doesn't cut it for us.

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