Rinsing bath - how to disposal ? when to change?

Nearly subject :  http://support.formlabs.com/entries/23704573-Clean-er-Alcohol-for-Clean-er-Prints

“This recommendation (about UV) has not been written “at random” and I want to understand what motivated this writing.”

The reason for UV curing is that once the resin polymerizes into it’s solid form it is relatively inert, and can typically be disposed of in normal garbage, as any other [non recyclable]  plastic. [check your local laws to be sure] In the liquid resin form, you likely have to treat it as hazardous waste, like paint, and take it to your local chemical disposal facility, as it could leach into the ground water system if disposed of improperly.

As for the used alcohol, that should be disposed of as hazardous waste. Another option might be to evaporate off the alcohol and burn that [as it will be clean] and then dispose of the remaining residue by exposing it to UV to cure it, and then throwing it out, or, as above, taking it to your local hazardous waste drop-off.  At the very least, evaporating off and burning the alcohol minimizes the volume of waste you need to dispose of.

@Mark Loit

In France, legislation has adopted the principle that the polluter pay. This principle drives actually want to reduce industrial waste.
This is indeed why I would like detailed informations on the method by evaporation of the alcohol, or best a direct testimony of someone who really practices it.
I would like to be assured that this method is not dangerous in its implementation.

I was in the chemical industry for 27 years and handled IPA 20,000 litres at a time which was fun!

To be totally honest with everyone who is interested in this subject you are each going to have to discuss the subject with your local authorities to find out how the contaminated solvent is to be disposed of in your area.  I think you will find that most Western countries expect the polluter to pay.

Countries have very different laws for handling chemical waste which have to be respected.  You will need an MSDS for the IPA which by law the supplier should make available to you.  You have the MSDS for the resin from the Formlabs web site so you have all the information the authorities will need to advise you.  If you are a business you may have different guidelines compared to a person in a private residence.

It’s also worth mentioning here that storing over a certain quantity of “Flammable” material  in your property can invalidate your insurance if you have a fire.  So be sure to check with your home insurer what their rules are.  I use IPA in another process and have extended my insurance to store up to 25Ltr  IPA in a flammable cabinet among other solvents in an outbuilding.  I know some are going to say “but I park my car in the garage which is joined to the house and that’s full of petrol”  well yes you do and your insurance will already take that “risk” into account.  That’s why they ask you where the car is parked.

Practices like evaporating the IPA off or burning it may be against local regulations after contamination.  Businesses may have VOC limits limiting what they can evaporate anyway.  These practices have inherent risks so take precautions.  If you are using IPA only for the printer the amount of waste is not going to be too high so the costs are going to be very low I am sure.

@Nigel Wagstaff, TY very good advice for insurance !

How about not even trying to dispose of it, instead recycle the IPA to pure IPA and then just solidify the remaining resin in the sun?

Keeping it simple along the line or similar to something like this?   http://www.brewhaus.com/instruction-pages/Amazingstill-Instructions.pdf

Marc, the still is perfectly feasible in a laboratory or industrial environment.  The thought of heating alcohol above it’s flash point in an enclosed environment like the home will one day go horribly wrong.  I am not Mr.  Health and Safety here just trying to point out the risks.

The heaters do look like special units, and designed for immersing in weak Ethanol solutions, but I am not sure they are designed for immersion in almost pure alcohol as we will have.  If the electrical insulation fails inside the heater at any time and there is a spark I can assure you it will blow every window in your house out an your ear drums in!

Iso Propyl Alcohol  is not Ethanol.  It’s an industrial alcohol which is more toxic compared to Ethanol commanding some respect in use. It burns very hot with an almost invisible flame so you should practice strict no smoking or ignition sources in the vicinity and you should avoid skin contact as it will adsorb through the skin. Like most chemicals, used correctly it is safe.  Store it like your household cleaning chemicals locked away from children and ventilate when open.

Nigel

@Marc Collinson, As Nigel Wagstaff said, it seems to be a bit dangerous with a flash point at 13°. Also, i’m in France where distillation as a hobby is illegal.

Thanks for the warnings for me and all the others reading here the explosive/toxic issues surrounding IPA as a volatile

cannot be over emphasised, see my own posts a while ago below.

http://support.formlabs.com/entries/23371721-Set-Up-the-Form-Finish-Kit

The post was only an example of how simple an evaporator and condenser could potentially be that heater is a no no

under rated too hot ignition source in fact even plugging it in to a socket near to IPA and vapour is way too dangerous!!!

I was thinking more along the lines of adapting that simplicity to something with a transparent top/lid black internal bucket

and it all sat in a shallow tray of cold water/ice?

Therefore only works if used outside on a warm or sunny day is where I was trying to go.

Just a thought?

The above missed out the arrangement as was in the early link/post where a large bucket has a smaller black bucket raised inside it the larger bucket/container has a transparent top and is sat in a shallow tray of cold water.

Or an even easier construction just hang the smaller black bucket from a hook fastened below the transparent lid.

All low cost very very simple may need refinement but better than 1000’s of Form owners dumping these chemicals.

I’m just going to bottle mine up into mason jars and sell it to the locals as Resin flavored Moonshine.

I kid I kid…

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@Jory, I have the same questions and hoped to find a link by now to that article you’re working on. Any chance it’s ready and posted somewhere?

Thanks.

@Kevin I’ll take 7 bottles.

@Chris We have written up an article and it can be found here: https://formlabs.zendesk.com/entries/24677668-Disposal-of-Waste-Resin-and-Used-Isopropanol-Alcohol-IPA-#ipa

Please keep in mind, as stated previously, we are unable to give exact disposal instructions as legal requirement vary from place to place. I hope this article helps!

Sorry, I’ll do a reply in french since it’s related to France :slight_smile:

sand tz : en général, les déchetteries municipales ont un dépôt spécial pour les produits chimiques et toxiques. Il suffit simplement de mettre ton IPA dans une bouteille fermée hermétiquement et d’inscrire bien gros ce qu’il y a dessus. Je précise toujours quand je dépose mon alcool ce que c’est aux personnes sur place  vu que c’est hautement inflammable.

Et pour information, un sujet “entre français” à été ouvert sur ce même forum :  https://formlabs.zendesk.com/entries/26943843-French-language-speaking-Form1-users

Has anyone actually been successful at evaporation. What you are left with is jello. Not something you can just throw out. I am guessing we just need to take it to the haz waste depot and pay.

You definitely know to change the bath when it looks like this:

Here’s a different angle…:

How do I handle this as it’s a huge piece of jello? Kind of like a solid, kind of like a liquid.

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Oh my.
Does it have pseudopodia?

Maybe let it ooze out into a tupperware container, then leave it in the sun?
I doubt it can ignite with THAT amount of resin in it.

That looks thick enough you could probably print with it!
(I kid. I kid. Dont do that)

All low cost very very simple may need refinement but better than 1000’s of Form owners dumping these chemicals.