fixing my condencer...

[amikkola]

i did a water run a while ago... and it didnt go to well, my condencer (the 1/2" copper tube running through a bucket of water) didnt work to well...

it seems clear to me that there obviously isnt enough surface area on the strait tube in the cooling water.

ive figured that i should go get some of that... condencer tubing... the flexable copper pipe that people use to coil and send the vapor in a spiral through the condencor water.

My questions are: Can i safely go from a 1/2" cross sectional area to a 1/8th " or whatever the condencer tubeing comes in? A decrease in area will create a increase in pressure if im correct, and i just wanted to konw if that was safe.

and on a side note, does anyone konw about how much a length of condencer tube will cost? and any addapter nessisary to go from 1/2" to the width of the condencer tubing. thanks in advanced.

[Grayson_Stewart]

A decrease in area is going to create an increase in the speed the vapor travels through the tube. What length is the condensor and what amount of heat is being applied? It may be fine because there is alot less heat to draw out of alcohol vapor rather than plain old water.

[amikkola]

hmmm... it was insufficient... ill say that in the least... i kinda go lazy and didnt realy plan my condencer too well, it was about.... probobly 6" of condencing lenght on the copper pipe...in addition, i put my collecting jar in an ice bath, and there was still steam pouring out of it...

it took me 45 minutes on high on my electric stove to get the 1.5 ish gallons up to boiling, i think its 15KW

it just concerns me because the liquid seemed to... for lack of a better phrase... explosivly boil, all at once, there was a huge rush of vapor, and i would assume it might pressurize if the tubing suddenly went from 1/2" to 1/8"... I'm actualy hoping for simplicity sake that this will be fine.

[The Chemist]

it just concerns me because the liquid seemed to... for lack of a better phrase... explosivly boil, all at once, there was a huge rush of vapor, and i would assume it might pressurize if the tubing suddenly went from 1/2" to 1/8"... I'm actualy hoping for simplicity sake that this will be fine.

A couple of boiling chips (broken terra cotta flower pot) in the wash will solve that problem.

[DBM]

amikkola;
At some place near the top of your colum install a thermometer to measure your vapor temp. When the vapor temp gets to 160* cut back on your heat. Try to hold the temp at 165* for 15 or 20 min by manipulating the temp. Then slowly raise the temp to 175/178*. At this point you should have a steady stream of drops coming from your condenser. I usually set my output to as slow as I can get it and still have a steady stream,(not drops).

[Yttrium]

Although I douubt there would be a dangerous buildup in pressure if you started using 1/8th inch tubing, you would probably get a lot of sputtering. I would guess that the tube would sometimes clog with fluid and you would get ocasional gushes instead of a nice consistent drip.

My suggestion would be to use several feet of 1/4 inch copper tubing coiled in a water bath. 6 inches of condenser isn't going to be enough regardless of what diameter the tubing is.


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