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07-05-2021, 12:16 PM   #166
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As I recall it wasn't some much an ecological issue but rather economic spurned on by the sky rocketing prices of silver. Why pour the silver down the drain when you can recover it and turn it in for cash. Probably more the 70s than the 80s.

07-06-2021, 12:30 AM   #167
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QuoteOriginally posted by Wheatfield Quote
It has never been profitable to recover silver from photography.
Thanks for this, I wasn't aware at all. I do recall that the manufacturer of the Washi films is grateful for digital: had everything remained silver-based, it would not be sustainable in his opinion in the long run.
07-06-2021, 08:46 AM - 1 Like   #168
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QuoteOriginally posted by Wasp Quote
So silver recycling was just a way to appear green before it was it thing? My bad. Thanks for the lowdown.
To an extent it was greenwashing. There was enough other stuff in colour chemistry that was far uglier than silver thiosulfate, which is pretty inert from an environmental point of view. It was sold to the industry as "the right thing to do, and you'll even make money doing it", the reality was that while it was sort of the right thing to do, once the equipment and power to operate it was factored in, it was, at best, a very slow money maker.

The machines I ran gathered silver, along with anything else that could be cracked out electrically, on a spinning anode. The anode was spun to create turbulence on the tank to ensure as much liquid as possible got close enough to the anode to allow for the electrolytic process to happen.

The commercial lab I worked at when silver recovery became a thing had a great big machine with at least a 20 gallon holding tank. Every few months we would take the anode out and break the silver bearing ore (it was far from pure silver) away from the anode drum, rinse it clean and send it off to wherever it went for processing. A few months later, we got a breakdown of the percentage of silver in the ore, how much silver was extracted from the ore, how much it cost to recover the silver from the ore, and a disappointingly small cheque that was generally enough to buy a pizza for the leadership team and not much else. This was a lab that was processing and printing upwards of 15,000 rolls of film per day during the peak season, 3000-5000 rolls of film off peak. I don't think anyone ever bothered to do an onsite breakdown of what it actually cost in electricity to run the thing.

Later, they came out with a new and improved method of recovery that used tanks of some sort of sacrificial material that was less offensive than silver, and the recovery was done via an ionic exchange in much the same way that a water softener removes calcium from the water and replaces it with much more soluble sodium. I wasn't involved in the financial end of things at that point, so had no idea if it was financially viable, but the tanks would clog up frequently and need to be taken out of service, and the system was no good for a high volume commercial lab. It was a minilab sized solution for labs generating a few hundred rolls of film per day.
I'm not sure where the tanks had to be sent for processing, but it wasn't local, so shipping of them would have been factored into the cost, and while the dry ones were only 25 or so kilos, their return weight was much greater due to the fact that they could never be fully drained.

I recall reading that in California, the government mandated how much silver was allowed to go down the drain as a way of forcing labs to do silver recovery. Ironically, in many places in that region, the naturally occurring silver content in the water was higher than what was mandated by the State.

Was it the right thing to do? It's hard to argue no, but depending on where your electricity came from and how much it cost, it was at best a break even from an environmental point of view, and probably not a money maker for more than a few labs that had really high volumes, were able to buy cheap electricity, and had managed to pick up a machine for a really good price.

Anyway, this is so far off topic as to be in another universe.

---------- Post added Jul 6th, 2021 at 09:51 AM ----------

QuoteOriginally posted by Smolk Quote
Thanks for this, I wasn't aware at all. I do recall that the manufacturer of the Washi films is grateful for digital: had everything remained silver-based, it would not be sustainable in his opinion in the long run.
I think with digital we have just shifted the environmental load from silver to other manufacturing processes. Consider that in the film days, it was fairly rare to buy a new camera every couple of years, and a new computer every couple of cameras to keep up with the new and larger files.

Anyway, for the small B&W darkroom user, the level of chemistry going down the drain isn't going to hurt anything, though if a person is on a septic system they might want to look at the ramifications.

Last edited by Wheatfield; 07-06-2021 at 09:17 AM.
07-06-2021, 10:13 AM - 2 Likes   #169
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QuoteOriginally posted by Wheatfield Quote
Consider that in the film days, it was fairly rare to buy a new camera every couple of years, and a new computer every couple of cameras to keep up with the new and larger files
Yes, I commented in another thread that recently we have gotten into the bad habit of purchasing a new camera every few years in order to get a new sensor {in the Age of Film, we would have changed films perhaps}. It is time to get out of this habit, and get back to actual photography {in 'Pentaxese', to 'having fun'} as our main activity.

12-19-2021, 04:57 AM   #170
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Regarding silver from prints and film development... It is always the two topics environmentally and economically feasible. It also always depends on where you draw the boarder of your analysis.

Regarding cameras/sensors. I would love to see more trade in, upgrade and recycle programs. Recycle much in the sense of reuse, since that is the best form of recycling
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