Switch to English Language Passer en langue française Omschakelen naar Nederlandse Taal Wechseln Sie zu deutschen Sprache Passa alla lingua italiana
Members: 70,224   Posts: 1,532,655   Online: 851
      
Page 1 of 2 12 LastLast
Results 1 to 10 of 12
  1. #1

    Join Date
    May 2005
    Shooter
    4x5 Format
    Posts
    182

    Environmentally Sound Disposal of Pt/Pd Dev. and Clearing Baths

    What's a strategy for environmentally sound disposal of Pt/Pd developer and clearing baths?

    I plan to use potassium oxalate for my developer and ferric oxalate for my sensitizer. I know that potassium oxalate has toxic effects. I was thinking of using hypo clearing agent for clearing. But as long as it clears for archival purposes without bleaching the image, I could use something else.

    Does mixing potassium oxalate with a given clearing bath offset the toxic effects of the dev? Is there some way to treat discarded dev and/or clearing bath that renders these discarded chemicals environmentally benign? Does it make sense to bring discarded chemistry to a neutral pH of 7 before disposal?

    Is there documentation that someone knows of that addresses these disposal related questions?

  2. #2

    Join Date
    Sep 2002
    Location
    Tijeras, NM
    Shooter
    Medium Format
    Posts
    1,246
    Oxalic acid is found in high concentration in Rhubarb leaves and in Skunk Cabbage. Although it does bad things in our bodies nature doesn't have any trouble dealing with it.
    art is about managing compromise

  3. #3

    Join Date
    Sep 2002
    Shooter
    Large Format
    Posts
    4,530
    Since the developer is reused, you dont have to worry about heavy metals on the environment as what you will be introducing will be in negligible amounts, certainly you have to worry more about disposing of fixer than what you would get in the wash from a pt/pd print.

    The clearing agent will only remove ferric oxalate, which will be easily broken down by the environment. IMO pt/pd is one of the most ecological friendly processes.

  4. #4

    Join Date
    Sep 2002
    Location
    State College, PA
    Shooter
    ULarge Format
    Posts
    336
    Yup, I understand two pounds of Spinich have enough PO to kill a person, but it apparently causes no harm for regular disposal.

    Just one more reason I won't eat the stuff.

    I've discussed metals reclaimation with Bostick and Sullivan, and they generally state that the amounts are in such low concentration in the clearing baths to make it very difficult to make a meaningful reclaimation process.

    My impression is that the silver in the film and papers are easily reclaimed and in quantities that it is done (and mandated in many areas), but that is not the case with pt/pd.

    Jorge can correct me if I'm wrong, but since they are noble metals, they pose no risk for humans or environmental impact if they are released in small quantities? That's always been my understanding, but I may have it wrong.


    ---Michael
    www.mutmansky.com
    B&W photography in Silver, Palladium, and gum bichromate.

  5. #5
    scootermm's Avatar
    Join Date
    Jun 2004
    Location
    Austin, TX
    Shooter
    ULarge Format
    Posts
    1,867
    Images
    235
    so is it bad if I make a grilled cheese sandwich on the same hotplate that I warm my developer?

    lol. just kidding.

  6. #6
    EricNeilsen's Avatar
    Join Date
    Dec 2005
    Location
    Dallas
    Shooter
    4x5 Format
    Posts
    67
    Neil, Some of the concerns would be what type of contrast agent you are using. If you use Hydrogen Peroxide there would be nothing more hazardous than the developer only. If you are using dichromates in your developer and regularly dispose of it, you may be adding a hazardous substance to the environment.

    Hypo Clearing agent shouldn't be much of an issue.

    And unless your volume is many many gallons a day, your small amount of affluent shouldn't make much of statement down stream.

    I'd be more concerned about the harzards in the darkroom for yourself than the consequences from a small discharge. The powders of PT can be linked to asthma, etc. Practice good darkroom safety and things will be fine.

  7. #7

    Join Date
    May 2005
    Shooter
    4x5 Format
    Posts
    182
    Indeed. I got myself a full facemask with proper particulate filters for mixing chemicals.

    One reason for asking is that I want to do this as part of a business, and I may need to make a case to our local town officials on disposal, safety, etc. So, having documentation that addresses strategies for disposal, the need, quantities, kinds of risks, etc., of pt/pd related chemistries would be helpful.
    Last edited by Neil Poulsen; 01-24-2006 at 11:28 PM. Click to view previous post history.

  8. #8

    Join Date
    Sep 2002
    Location
    Tijeras, NM
    Shooter
    Medium Format
    Posts
    1,246
    We have given you advice that suits the hobbiest. To make what your doing 'legal' for business is an entirely different matter.

    I would consult a book on lab safety about the best ways to store chemicals, ie locked cabinets, seperate oxidizers, things like that.
    I would seriously consider finding someone who takes wastewater instead of dumping down the drain. Figuring out what you can do legally is probably not worth the hassle.

    Quote Originally Posted by Neil Poulsen
    So, having documentation that addresses strategies for disposal, the need, quantities, kinds of risks, etc., of pt/pd related chemistries would be helpful.
    art is about managing compromise

  9. #9
    EricNeilsen's Avatar
    Join Date
    Dec 2005
    Location
    Dallas
    Shooter
    4x5 Format
    Posts
    67
    Quote Originally Posted by Neil Poulsen
    Indeed. I got myself a full facemask with proper particulate filters for mixing chemicals.

    One reason for asking is that I want to do this as part of a business, and I may need to make a case to our local town officials on disposal, safety, etc. So, having documentation that addresses strategies for disposal, the need, quantities, kinds of risks, etc., of pt/pd related chemistries would be helpful.
    Neil, THis is what I do; custom printing. I tried very hard when I first got to Dallas to find out the proper disposal to meet city regulations. I could not get a good answer. many regulations or written for large industry, even if you are doing a good platinum/palladium printing business you are not going to dump that much down the drain. I larger concern would be for those on wells. The amount of wash water dilutes most of what you dump to very small levels. PT, PD will most likely plate out long before it gets into the water system. I would contact the local sewage treatment officals and find out about the ppm for all the chemicals that you are using. Give them a quick idea of how much you might be doing. They should be able to help.

    I ran most of my chemicals out to an evaporative system in Taos when I lived there. THat way it was recovered as a solid.

    Is there a way here to get direct emails of threads?

  10. #10

    Join Date
    May 2005
    Shooter
    4x5 Format
    Posts
    182
    I've been checking with local authorities. Neither pt nor pd is on their hazard list. If I can get away with it, I'll use the same development bath, filter it, etc.

    I'm considering how I might contrive an environmentally friendly clearing bath based on citric acid and edta and whatever else I need. I'm told that some agriculture people add edta to the soil.

Page 1 of 2 12 LastLast


 

APUG PARTNERS EQUALLY FUNDING OUR COMMUNITY:



Contact Us  |  Support Us!  |  Advertise  |  Site Terms  |  Archive  —   Search  |  Mobile Device Access  |  RSS  |  Facebook  |  Linkedin