recycling wash water as grey water?

[toddstew]

Those of us in the Southwest U.S. are in the midst of a mighty drought. Hence, everytime I print or process film, I feel guilty about the amount of water I am using to wash my prints and film. Does anybody have any experience using this water to say, water plants? Will the water kill the plants? I process my film with PMK, my prints are either palladium or silver gelatin in formulary 65. Thanks for any advice.
Todd

 

[jeffneedham]

Todd,

From what I understand, it is really not good to dump water that has been mixed with fixer. Having a septic, I've been warned not to dump it down the drain. I treat it as a household chemical and store it in five gallon buckets until I can get it to the transfer station. I'd venture to say that you might want to do some more research before dumping toxins on plants, or even worse putting them into the ground.

 

[toddstew]

Yeah, my fix gets dumped into a barrel, but after a rinse or two how toxic is the water? Your point goes right to my question. I feel guilty about using this much water, but I don't want to poison the ground. I wonder if there isn't some sort of coal filter system to clean the water before watering plants.

 

[jeroldharter]

I wouldn't feel too guilty about the photography. Living in a city in the desert is in itself a stretch for the resources. A few gallons of water to wash some film is just a spit in your neighbor's pool. I used to live in a house with a mound septic system and worried about putting chemicals down the drain. From everything I read, I had nothing to worry about so long as I did not use commercial volumes of chemicals.

 

[toddstew]

So Jerold, you're saying not to feel guilty about pouring the water on my plants or not to feel guilty about running it down the drain? I guess it's guilt about one or the other. Suddenly I'm beginning to feel Catholic!(just kidding)
Todd

 

[jeroldharter]

Just joking around. But I think that if you are reasonably conservative in the darkroom you are a small problem relative to the impact of routine life in the city in arid climates. Also, a drought might be a good excuse to go someplace wet to take some photos for later processing.

 

[Curt]

Where I live and in many places the waste water goes down the drain, to the street, to the pumping station and into the waste water treatment center on the edge of town. Over there they don't worry about the home darkroom waste being blended in with the condoms, Q-tips, tampax and any other s**t flowing their way. If they aren't worried then I'm not worried.

 

[david b]

I sometimes use my rinse water to water some of the trees in my yard but this is only pertaining to the final rinses.

david b in santa fe

 

[Wayne]

My darkroom sink drain carries wash water (only) straight into the yard. How many hundreds of gallons of wash water are there for every once of already diluted working solution chemicals? A lot. Drain prints and trays well before washing them. I dont worrry about that at all, and I dont dump chemicals into my septic either.

 

[david b]

I have a friend who's darkroom is setup to water his garden.

 

[Kino]

Well, I don't think the wash water would be particularly harmful to your lawn or trees if the PH is near neutral. I wouldn't drain it into a garden plot as a general rule; just to be safe.

If it bothers you enough and you can throw the resources at it, you could reclaim the water by building a solar still (google it). The water would evaporate from the bottom, leaving the chemicals behind and recondense on the inner liner to be used for anything.

You could also build a sump and line in with charcoal, but it would have to be maintained and could be a pain...

Just a few thoughts...

 

[david b]

If you are washing paper for 45 minutes, how harmful could it be after the first 5 minutes or so?

 

[Donald Qualls]

If you precipitate the silver from your fixer and wash water, the fixer, developer, and wash will all work fine to water and slightly fertilize plants. Only the silver will remain toxic after exposure to air for a while (and most of your process chemicals aren't terribly toxic to begin with); aside from silver, everything used in the straight B&W film and print process (except selenium and other toners) can go straight into the garden. Dichromate and permanganate reversal bleaches are the other exception (though permanganate is a lot less unfriendly than dichromate in that regard), but there aren't that many folks doing B&W reversal.

Wash water shouldn't be a problem at all -- there'll be darned little fixer in that, and far less silver. Used fixer itself, after a few days reacting with steel wool, can be filtered off the silver precipitate and dumped on the garden, and used developer can go straight out there if you choose (though if you use pyro or pyrocat, I'd suggest letting the developer stand in an open tray for 24 hours before tossing it, to let the relatively toxic developing agent oxidize into an inactive product).

 

[toddstew]

Thanks everybody for the comments. Donald, can you tell me a little bit about putting steel wool in exhauted fixer? I've got a big ol'barrel that I need to take care of. Man david, we are in for quite a dry, fire-full summer,huh? You're right Jarold, I need some sort of wet surroundings for a bit. We're at about negative 6% humidity here!
Thanks again for the comments,
Todd

 

[david b]

We are gonna burn!!!

I am prepared to help and to photograph what I can.

 

[argus]

If you'd ever know what's in rivers in Belgium.

A few months ago the water of the Zenne, flowing under and through Brussels was tested downstream from our capital.
The tests pointed out that at least 1/20000 inhabitants (IIRC) of Brussels must be using heroin!

G

 

[toddstew]

And everybody in Italy is on the cocaine!

 

[glbeas]

If you consider that sodium thiosulfate is put into fish tanks in very dilute concentrations to neutralise chlorine in the water I'd worry very little about using rinse water for watering the flowers.

 

[Donald Qualls]

Donald, can you tell me a little bit about putting steel wool in exhauted fixer? I've got a big ol'barrel that I need to take care of.

Pretty simple -- go to the home improvement store and buy the steel wool they sell for wood finishing (comes stuffed in plastic packs about the size of a loaf of bread). For each gallon of spent fixer, drop in two steel wool balls, cover, and come back in a week. You'll find the interior of the container heavily plated in silver, and lots more silver sludge in the bottom of the container, while the steel wool will mostly have been eaten up by the reaction. Decant, or preferably filter the liquid through paper coffee filters or similar (slow going, give it time), and the clear or colored liquid that comes through the filter is effectively silver-free fixer with some iron added to the solution. That's the stuff that goes on the garden. Roses are said to love the stuff (they like sulfur, apparently, and iron doesn't hurt them a bit), but it should be good on tomatoes, squash, etc. as well; likely everything in a typical flower or vegetable garden will be okay with it if you dilute it a bit (say, with some of that wash water).

The sludge in the container is impure silver; if you're the DIY sort it can be melted (outdoors!) in a foundry and cast into ingots for later resmelting, or it can be reacted with nitric acid to make silver nitrate solution that will work just fine for a number of alternative processes such as salt prints, kallitype, van Dyke, etc.

VERY IMPORTANT that you do *not* do this with fixer that's been used after selenium toner!! That can be left in an open pan (where children and animals can't get into it) until all the liquid evaporates, and the residue treated as household hazardous waste (similar to old cans of paint, drain opening lye that's hardened, etc.); most communities have a means of safely disposing of the stuff, though they're almost certain to want to know what they're dealing with (you'd tell them "photographic fixer contaminated with selenium toner", which they will dutifully write down after asking you how to spell selenium).

If you consider that sodium thiosulfate is put into fish tanks in very dilute concentrations to neutralise chlorine in the water I'd worry very little about using rinse water for watering the flowers.

Even more so -- the same chemical is used in swimming pools for humans (as is sodium sulfite) for the same purpose. If you don't tone your prints or use exotic developers, silver is the most toxic material in the printing darkroom, and once reduced to metallic form, it's nothing to worry about.

 

[toddstew]

Thanks Donald. I'm going to the store today and do this.
Todd

 

[Michel Hardy-Vallée]

The sludge in the container is impure silver; if you're the DIY sort it can be melted (outdoors!) in a foundry and cast into ingots for later resmelting, or it can be reacted with nitric acid to make silver nitrate solution that will work just fine for a number of alternative processes such as salt prints, kallitype, van Dyke, etc.

(...)

If you don't tone your prints or use exotic developers, silver is the most toxic material in the printing darkroom, and once reduced to metallic form, it's nothing to worry about.

Donald, what do you suggest for the non-DIY among us to do with the sludge of impure silver? Should it just go down the drain again, or must it go to the hazardous waste disposal facilities?

 

[Donald Qualls]

Donald, what do you suggest for the non-DIY among us to do with the sludge of impure silver? Should it just go down the drain again, or must it go to the hazardous waste disposal facilities?

First suggestion would be to contact a local mini-lab processor and ask them if they could add your silver to their recovered silver, which is picked up for them (often for free, the disposal paid for by the silver metal reclaimed).

To elaborate, mini-labs generally run an in-line silver recovery unit to extend fixer life and comply with environmental requirements; this unit produces silver sludge similar to that you'll find in your fixer bucket after steel wool treatment. Since silver is considered a "toxic heavy metal" (for waste disposal purposes -- doesn't mean silver jewelry is dangerous, or even silver eating utensils, though using *nothing* but silver to eat from can lead to argyria, the source of the "blue blood" expression for the very rich or royalty), it can't be disposed of down sewers or in common trash (at least by businesses, who typically produce hundreds of times as much as home processing would). So, the silver sludge is "disposed of" by "helpful" souls who take it away and, usually, smelt it into purer form and sell the resulting ingots -- potentially back to companies that process the silver into film, but there are many industrial uses for silver. These folks make enough selling the silver that they frequently don't charge for their service of removing the toxic waste -- and as a result, many mini-labs will be happy to add your silver sludge to theirs for disposal.

 

[Bob F.]

From reading, it is my understanding that the major problem with spent fixer is the silver: it is poisonous to the microorganisms that process our sewage. Once the silver is removed, it is relatively harmless to dispose of and can be used as a dilute plant feed as Donald suggests.

Feelings of guilt can be assuaged by asking your local water company how many millions of gallons of water is lost through damaged and badly maintained supply pipes in an average year. Add that to the amount of water wasted in industrial processes and although it may not entirely render you guilt-free, it will put your personal water use into perspective...

Cheers, Bob.

 

[Kino]

Somewhere around here I have plans for a small silver reclamation unit scaled for a small darkroom that works a lot like the large rotary units we have at work.

It is a simple affair with flexible metal plates that you put the fix into and turn on the current. Minutes to an hour later, you remove the fix and find pure silver plated to the anodes, which can be recovered by flexing the metal plates and gathering up the flake silver.

The only possible problem is if you pass too high a current, you liberate sulfur compounds and ruin the fix.

I can have a look around if anyone is interested in the plans.

Frank

 

[david b]

The computer company "Intel" is in Rio Rancho NM, which is about 20 miles outside of Albuquerque. I heard they use 1 million gallons of water per day to make computer chips. When asked to cut back, they stopped watering their corportate lawn.