Rotovap

CothermanDistilling

I think A and V use same vapor duct, right? I am ordering just the V condenser side glass. (I need to verify mine is the standard 29/32 and not the 24/40 or 29/42 before ordering a larger evap flask)

Crap, now looking at page 6 of the Ace Glass PDF, I see that the A tube is longer than the V tube, but I don't think mine is... I think mine might have the short tube... I think they just tossed the A glass on when selling, which the V thermocouple sensor woudl also agree with... will look today

If this A glass needs to have vacuum pulled from the top (not sure), then it will need a spigot put on by a glass blower... it seals with the tapered joint, but the 'turn valve' outlet has the glass hose barb broken off... but I will gift it to you if I get V glass...

Here is what I am looking at getting:

grim

Yeah the vertical coil and cold finger condensers use the short duct, the horizontal uses the long duct.

I have a short duct and the horizontal, which is also a mismatch. However, my horizontal is an older model, with no temp probe accommodation.

The horizontal pulls the vacuum from close to the flange, so it needs the long duct to take the vapor to the top of the coils. The vertical is the opposite, and pulls from the top, so the vapor would need to pass all the coils to be evacuated.

CothermanDistilling

OK, I have a short vapor duct with 24/40, they mismatched me too...

Here is a pic of the flask, short end of the tube, and the condenser.

CothermanDistilling

OK, been off-line for a while... went to New orleans with the better half for her birthday... got my new condenser in and put a working cable between the vacuum pump and rotovap... tomorrow is the day to make something... cucumber or jalepeno? hmmmm....

https://www.youtube.com/watch?v=5QI22LunEoM

punkin

Quite a cool toy mate, i bet you have a ball.

grim

... and that's why that setup originally cost more than $10,000. Trickiest piece of extraction kit there is.

richard

But one needs to ask the question, is this unit commercially viable for a distiller for the required quantity to be produced.

Not too small ??

grim

I believe you can fit a 5l evaporation flask, which would hold about 2-2.5 liters of neutral spirit, and 2-2.5 liters of nearly equal strength distillate.

I use it to make flavor concentrates. For example, my cucumber extract is so strong, I use about 2ml per bottle of gin, so that 2500ml is enough for 1250 bottles of gin.

I only run a 2l evaporation flask though, and make 1l of extract at a time.

Vacuum distilled extracts of heat sensitive compounds are FAR superior to vapor distilled. Fresh flowers are crazy. We have a huge number of honeysuckle bushes that border the railroad tracks near my old home. I'm planning on spending a day picking honeysuckle to do an extract.

Like I said before, cucumber and jalapeño are some of my favorites.

RobertS

May I ask how you account for your flavor extracts? I assume you have them in your processing account, then record usage in your batch record? I haven't made separate flavors yet and always get nervous around new book keeping.

CothermanDistilling

@RobertS said: May I ask how you account for your flavor extracts? I assume you have them in your processing account, then record usage in your batch record? I haven't made separate flavors yet and always get nervous around new book keeping.

I think there are a few ways, you can write the few liters off as lab samples removed from bond, and label then as such... (I saw this at a gin class held at a commercial distillery) or you can consider it unfinished spirits going into the mix and then the rotovap and not a distilled spirit 'produced' for consumption coming out ( similar to how vanilla extract is 70%, but not considered a distilled spirit... ) it never hits production, except maybe the .1PG on a quarterly inventory of unfinished spirits.

FYI - I do not feel comfrotabel going into further discussion of this , I would direct you to David Dunbar on ADI forums..

RobertS

I appreciate you going as far as you did, and all the work David does. You would think bookkeeping questions like this would be answered in the regulations.

CothermanDistilling

Here is this mornings Cucumber extraction... a lot to learn, need to take notes on every ingredient, they all seem to behave a bit differently...

https://www.youtube.com/watch?v=yulOY1Sg1YQ

grim

Skin, Flesh, Seed - these all have different flavors and aromas, not all are desirable.

Consider not using all of the above.

CothermanDistilling

I am picking up what you are putting down... :-)

yeah, that was the first run, I did habeneros and jalepenos and then this... it was a serious improvement over previous attempts with the lab still, (still great for things that are not 'tender' and susceptible to 100c temps heat...)

I am going to try parts like you said, and also other styles of cucumbers... that was 2 of the plastic wrapped 'hot-house' ones cause they were on sale for a dollar each.. I picked up some regular ones today and going to try one of them...

1. might reduce water bath temp 10 degrees c, as 60c(140f) can cook things... the 'backset', if you will, definitely had more 'cooked vegetable' aroma than I would want, but it was not that apparent int he spirit.. 50c, (122f) should be just fine...
2. deciding how much and strength of alcohol... I find myself wanting to use much higher alcohol with this so I am not vacuum distilling so much water, but not sure if that is right... with the lab still it was 1L of 100proof... with this I keep wanting to go to .5L of 190 with something like cucumber, because it has so much water to begin with.. maybe I need to start the ingredients and their water percentage and extrapolate total water?
3. I find myself starting at 200millibar and manually ramping down... there is not a ramp mode, is there?
4. this condenser has the port that uses vacuum to suck liquid out and inject it into the boiling flask.. , I could start with 1liter of 100proof, suck off the alcohol then add more (this is pretty advanced, I would like 100 still runs under my belt first)

grim

I use straight neutral, no dilution.

CothermanDistilling

I feel better now, thanks! It just seems the vacuum loves sucking out neutral... water, not so much....

grim

You are pulling vapor out the vacuum? Colder coolant or run at a higher temperature/pressure.

CothermanDistilling

no, just referring to the normal distillation being more difficult for lower alcohol concentrations... I do get a couple drops in the valve bottle if I let the condenser have condensation more than 2/3-3/4 the way up the coil, per the manual.

Drywall_Dan

@CothermanDistilling said: I find myself starting at 200millibar and manually ramping down... there is not a ramp mode, is there?

I don't Vacuum Distill but my gut wants to ask why not start at 60-80millibar and ramp the heat up from room temp to 50-60c slowly?

CothermanDistilling

that would probably be the preferred method... and it takes a while for the water to heat and the heat to transfer, so once I get 10-20 runs under my belt, I should be able to find a set of parameters to set, pull the vacuum, and turn on the bath... matching the speed of heating the contents to the boilover potential... I can also use how far the boiler is immersed to control the heating rate... also, there is an oh-shit button to instantly start venting and pause the pump, which is a great defoamer..

grim

Don't follow, you are bumping (boiling over) if you use higher proof, but you don't see it at lower proof?

The V-855 has more advanced features like auto distillation (using the vapor temp probe), the ability to distill with gradients, etc.

CothermanDistilling

It seems every time you increase vacuum there is a surge of fairly violent foaming followed by a nice boiling action that slowly subsides..

Supposedly the 850 does some of that stuff... I have the temp probe in place and working, I like it... I need to read more now that I understand the basic operation from a hands on perspective... maybe I want an 855... I dunno.. I would love ramping and auto shutoff once I know what parameters I want...

CothermanDistilling

yep.. 'gradient'.... I now want the 855...

V-850/855

• Easy operation with large control knob and 4" graphic display
• Timer function for process termination after pre-specified time
• Buchi Wizard -- quick and easy menu setup
• Solvent Library -- 43 solvents pre-programmed to simplify parameter selection

V-855 only

• Gradient and repetition function for gentle distillation of your most demanding solvents
• Stores up to 15 processes programmed using gradient mode
• EasyVac -- automatic process control based on vapor pressure detection
• Automatic distillation -- require unique stage probe

grim

@CothermanDistilling said: It seems every time you increase vacuum there is a surge of fairly violent foaming followed by a nice boiling action that slowly subsides..

Once you are at your target temp, don't try to drop it further, increase the bath temperature instead, one degree at a time.

Even the fancy vacuum control is pretty crude, it's easy to go over the edge trying to drop the pressure.

My pump may be smaller than yours in terms of vacuum rate. Does any of the docs you have indicate you can install a needle valve on the vacuum line to slow down the evacuation rate? I'm not sure if this will screw up the v-850 control program.

You trade off speed for the ability to make smaller vacuum changes during distillation.

CothermanDistilling

This V-850 combined with the V-700 vacuum pump will do a single stroke of the piston and then stop, which seems awesome... the glass windows on the side let you see the diaphram doing individual strokes.. It literally stays within 2 mbar of setpoint.... before I had the right cable connecting them, it used the valve on the wolf bottle, and that had a 50mbar swing...

grim

Yeah 50mbar is nuts, but even a few mbar is enough to bump when you are on the bleeding edge of a boil.

Once I start, I try not to drop the pressure for that reason. It's really easy to oops. It's easy to get used to atmospheric, where we're only talking about heat input, which happens really slow. Unlike a few pump strokes when you are already up to temp, that can easy take you well into boiling temp.

Other option is a bump trap on the 24/40 joints, it's nothing fancy just a bulb to give you a second or two extra time to correct.

Vaya_Con_Dios_Distillery

Check; rotary evaporation in the kitchen in; cookingissues.com

CothermanDistilling

@Vaya_Con_Dios_Distillery said: Check; rotary evaporation in the kitchen in; cookingissues.com

direct link, took a while to find it

CothermanDistilling

The first bottled product using the rotovap... amazingly simple to take one batch from the rotovap to make 11 cases of Jalepeno vodka that was significantly better than the previous batch... I took the corriander and pink peppercorn to near zero also, it just didn't need it... after 7 cases, I did a sample with 200g batch of rotovap'd habanero's and got 4 more cases with a big habanero nose and taste, and a little heat came through...

Rotovap did all I hoped for..

punkin

Looks and sounds fantastic. Love the packaging.