By taking what is consider waste in many shops and factories and recycling into a re-usable product makes this Instructable invaluable to many. Where I work, ACETONE used to be taken to a treatment plant or allowed to evaporate (non-intentional). By recovering the used acetone and RECYCLING it, I don't need to buy as much or pay for disposal. This machine can be used with many chemicals, but is isolated to acetone in this Instructable.
Building this mostly with used and recycled materials is beneficial as well. I only had to buy a few items. A commercial unit is thousands of dollars (I don't have).
In this state, the resulting solid mass is declassified as a hazard and can be taken to any waste management station. Check your local laws and regulations. Acetone is flammable, treat it as such. This means using the machine in a well ventilated area (outside) and keeping a fire extinguisher around.
All comments, suggestions, and advise are accepted. This is my first so be kind :)
I had most of these materials available as used items laying around the shop. Some were used, some were stock.
work cart (used alot ) Makes this unit mobile :)
various copper pipe and fittings (2", 1", 3/4", 3/8") and a torch w/solder and flux)
various pvc pipe and fittings (6", 4". 3/4") (and primer,cement)
old radiator (and rubber hose :) )
radiator fan (an A.C. fan would omit the next part. I used one that was wrecked)
D.C. power supply (purchased-Radio Shack)
water pump (spa type)
hot plate (definitly used) DONT USE AN OPEN FLAME TO HEAT!
pressure cooker (found at goodwill for 10 bucks)
ceramic chips (actually tumbler pieces)
screen (leftover from a project)
electrical box and switch (purchased-ACE)
epoxy (2 part)
water (glycol for winter)
Acetone can be dangerous in beginner hands. Learn about what your doing before doing it.
Before starting a project like this I recommend learning how to solder, join PVC, drill holes, ETC. I won't explain how in this Instructable because it would be really long and boring :)
I guess we'll start with the beginning of the process. Acetone is heated to it's boiling point. It then travels as a heated vapor through a tower (fraction column) filled with ceramic chips ( a simple replacement for steps) that allows some of it to condense and fall back into the boiling chamber. This keeps most of the contaminates out of the final product. Once the heated vapor reaches the top of the tower, it makes it's way into the cooling tower. The vapor is condensed into liquid and is dispensed out of the bottom of the cooling tower as pure liquid acetone.
Thanks to Wiki, you see the process is simple. This is the basic idea. I gave it a little flair by using a water jacket around the fraction column. I can allow super heated vapor to condense wherever in the column to increase the speed of the system.
Construction of the cooling tower is straight forward. It's a length of 4" pvc filled with water and capped. Then wrapped with 3/8" copper and enclosed with a length of 6" pvc pipe. Holes cut into the top and bottom of the 6" pipe allow the coolant (water) to flow around the 3/8" copper pipe.
I used through wall fittings for the coolant (1"&3/4"). The T at the top is where I fill the coolant. The expansion tank is connected to it when it's running.
I used another piece of 6" pipe as a base for the cooling tower. I sealed the 3/8" copper with epoxy.
Pretty much all of the leaks were fixed with epoxy :)
Construction of the fraction column is as follows:
This very simple depiction shows the principle. I used 2" copper pipe as the jacket and 1" copper pipe as the carrier. 2, 2x1x2 T's allowed me to travel a 1" pipe through it. I soldered a piece of screen at the bottom of the 1" pipe to keep the chips from falling into the boiler. Then I filled the 1" pipe with the chips leaving a little room at the top. I used reduction couples to get back to 1" for the the boiler and vapor outlet at the top. The vapor was then reduced to 3/8".
The bottom of the fraction tower is plumbed into the pressure cooker.
I mounted the radiator on a short side of the cart because it fit nicely. The fan needed a power supply that was 12v dc so I bought a 15 amp power supply from Radio Shack and wired it to my main switch. Then to the fans of course. The fans run continously when the main switch is in the on position (I might automate later). It has more cooling power than is needed for this process.
The hot plate is wired into the same main switch. It has a thermostat to control the heat. The power consumed in the process is hardly worth a mention.
Putting it all together. I used a few unions in the copper pipe so I could easily disassemble the cooling tower for maintenance or problems.
The hardest part is judging where the parts will line up to connect. As you can see in my pics, it is important to make things line up correctly. By assemebling the cooling tower and fraction tower before hand, you can plumb the rest of it easily.
I designed a bypass valve for the fraction column to regulate the amount of water that flows through it. This allows higher production of the unit.
Now that things are assembled you can leak test the cooling system:
1: Fill the system with water from the expansion port.
2: Turn on the circulating pump.
3: Check for leaks.
No leaks? Good for you! I had a few that were fixed with some epoxy :)
Fill your pressure cooker with nasty CONTAMINATED ACETONE!! (Good idea to filter it first with a paint filter or strainer)
1: Make sure all of the fittings are tight.
2: Turn on the hot plate to it's lowest setting.
3: Monitor the temperature at the TOP of the refracting tower. Acetone boils at 134 F. You'll actually see lower temps as the acetone boils off because there won't be any at the top of the tower.
4: Be patient, the vapor will make it's way to the cooling tower and condense into liquid. This takes awhile for everything to equalize. Slowly increase the temps until you see liquid.
5: When you see liquid coming from the bottom of the cooling tower make sure it is pure (clear).
6: If it is not, you have a problem. Probably too hot. Otherwise, collect it into another clean,empty acetone container.
You should be producing pure acetone at this point.
This machine produces pure acetone at the rate of 1.5 gallons an hour. You can get better results by turning up the heat and using the bypass valve to cool the fraction tower. This takes time and testing that I have not done. I'm satisfied because commercial units that cost at least $7,000 will barely keep up with this RECYCLED unit.
I thought of using solar power to heat the boiler, and a geo-thermal cooling system. This would be most economical.
I also had plans to enclose it, but it looks kinda cool the way it is. It also works, so why mess with it?