Chemical Disposal

[Camerashy]

I have always flushed my old chemicals down the sink, am I doing anything wrong, is there a better alternative?

 

[Ian Grant]

I worked for a company in the Jewellery trade and wa also specialised in Silver recovery from the photographic industry, hospitals etc. We had a licence to dispose to the drain once silver was removed from spent fixer (below 4ppm). I liaised with Water Boards including Thames (london) and also processing labs, it's assumed that amateur use chemistry goes down the drain and is so heavily diluted by the time it gets to a sewage treatment works to be undetectable and therefore not an issue.

If you can drop the silver out of spent fixer or Blix it can be recovered. Zinc powder works best but wire woll is easier an available in hardware shops.

Ian

 

[Camerashy]

Is it just a matter of putting wire wool in your old fix until it goes black. I have noticed that if I store old fix in 2ltr bleach bottles the inside gets coated with a black residue is this the silver?

 

[Ian Grant]

Yes, just place some wire wool in, it won't need much. If you use Comfort or Lenoir fabric softners in the washing machine the bottles are ideal for fixer they have a wide mouth than most bottles. The colloidal silver plates out on the plastic.

Ian

 

[Camerashy]

Yes, just place some wire wool in, it won't need much. If you use Comfort or Lenoir fabric softners in the washing machine the bottles are ideal for fixer they have a wide mouth than most bottles. The colloidal silver plates out on the plastic.

Ian

Yes, I do use the wide mouth Comfort bottles, thank you for your replies.

 

[David M]

I'm not entirely sure about this, but I seem to remember that silver chemicals should not be flushed into a septic tank as they disrupt the biological cycle that the tanks use. Not a problem for most people.

 

[thronobulax]

I'm not entirely sure about this, but I seem to remember that silver chemicals should not be flushed into a septic tank as they disrupt the biological cycle that the tanks use. Not a problem for most people.

If one is doing this in sufficient volumes as to disrupt normal bacterial processes in a septic tank, there are enzyme tabs that can be flushed to keep the little critters busy and working.

The larger issue for septic tank systems would be nasties like pyrogallic acid and pyrocatechin getting into the leach field and thereby into the ground and - possibly even - the water table. The fix for this is to pump the tank sufficiently often so as not to overflow to the field but I don't know how practical this is.

 

[Ian Grant]

In Holland commercial waste photochemicals are concentrated, dried, and fused together in a furnace.

Some people with septic tanks leave the spent chemistry to evaporate and bag it up for disposal elsewhere.

Ian

 

[Paul Kay]

We have septic tank and are very careful about what we allow to go into it as its outlet is into a stream and there is no alternative. I ould not put any photographic chemicals into it and am dubious about putting them into a mains drain at all myself. If I had a darkroom I would certainly try to dry chemicals out and dispose of the residue via the council.

 

[KenS]

I recover the silver from used fixer by a 'somewhat slower but 'less expensive' means. Used fixer is poured into a large glass carboy and add used but not 'dead" developer (from paper or film). stir well and let it 'sit' for a while. You will get a back precipitate of the purest form of silver. Repeat for as required then syphon off most of the clear liquid.. add more used fixer and more used but not dead fixer.
After numerous 'cycles' of so doing, wash the black precipitate 'numerous' times (the last couple being with 'distilled water'
Filter out the precipitate. and let it dry.

You now have the purest form of silver that can then be melted down.. and when cooled you will have a 'blob of silver that may be sold to provide the pennies for purchasing more film.. developer... fixer.. .. or whatever 'tickles you fancy'.



Ken