Breaking dabs hits 10^-4 with his pumps and set ups whilr running main body 
its crazy
Diffusions and turbos are fun toys, i hope to get one one day
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space is a deeper vac, 10^6 is deeper then 10^4th…
Yes i know that, i was saying wat was possible on earth… which is still way below (above? Lol)ur stated number
I dont think 10^-4 is lower then -29.92 mmHg.
Heres a little conversion chart I played with on google just now. No matter how many 0 you put after the . it will never get below 29.92 for the mmHg for here on earth. Space gets alot deeper then 10^6 too btw read this from Wikipedia. We can reach 10^12 here on earth but even space has a better vac rating.
Lol i see now u were talking in mmhg i was talking in inhg. Thats my bad. But why do u say its different based on altitude? How does the altitude change how well a pump can suck out an enclosed container?
I mean i get the concept of water boiling at different temps based on altitude, with the pressure differential (altitude difference) of an open container (open to the atmosphere) but
there shouldnt really be a difference if the SPD is running in Arizona or the himilayans, since its not really being affected by atmosphere
the higher the altitude the less pressure it takes to cause evaporation. At sea level you have alot more pressure holding the solution together then at high altitudes. Higher altitudes have thinner air and lighter air which makes evaporation easier. I use to live at sea level, now I live over 4000 feet above sea level. Ive noticed i cant pull my roto down as much because the air is thinner up here which means the vapor moves through my roto easier because its not so dense. The less dense air makes my vacuum pump less effective too because the air particles here are bigger so your vacuum doesnt move as many particles when you have light air compared to dense air. Heres a chart I found on the internet that shows total loss of vac at certain sea levels. Look at 4000 feet, i have a 13% loss in vac because of the less dense air. That means I can only pull down to a max vac of 25.8 inHG. I am by no means saying this chart is accurate, its just an example of how vacuum is effected by altitude.
The thing is in the himilayans the air particles are bigger. If you have the same size CFM pump you wont pull down as far up there because you wont be moving as much air because the molecules are bigger. Thats the way I understand it, I could be wrong though.
Heres the quote from the website I read that explained it
Because free air is less dense at higher altitudes (i.e. lower atmospheric pressure) operation at these higher altitudes has the effect of reducing the capacity and maximum vacuum levels attainable. In general, flow is not affected, only the maximum vacuum level attainable.
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Wow thanks for looking that up, i had no idea it affected vacuum i thought it was just things open to atmosphere. Im still kinda confused/baffled that u cant achieve good vac even with a turbo or diffusion in the himalayans or in the rockys
Im at 100ft, so ive never noticed or had troubles with vac.
What happens when u go below sea level? Lets say in a deep bunker by the sea?
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You can pull further down on vac the further below sea level you go. Basically what happens with vacuum is the atmospheric pressure is transfered to the flask or whatever you pull vacuum on when you evacuate all the air out of the flask. No air in the flask means no pressure inside the flask to fight the atmospheric pressure outside pushing in. At sea level the atmospheric pressure is 29.92 in Hg. Perfect vac at sea level is -29.92 inHg. I know this has to do with the fact that if theres nothing inside a flask then theres nothing pushing against the atmospheric presssure outside. Your vacuum can never exceed the atmospheric pressure because your atmospheric pressure is what causes the vacuum when you evacuate the air out. Think of it like this, atmospheric pressure is BASICALLY (dont quote me on this lol ) the squeezing force we feel applied by gravity to the air molecules around us. That “squeezing” force is what causes your vacuum when you evacuate a flask. That squeezing force can never be greater then itself. At below sea level you have increased pressure which results in a higher atmospheric pressure which means deeper vac
k trip on this, I got this off a chemistry site
A liquid will begin to boil when:
Atmospheric Pressure = Vapor Pressure of Liquid
If you think about it logically this mean ethanol will boil easier the higher up you are because the higher you go the lower atmospheric pressure you have. Now if you have a vacuum, this means you will not have to pull down on vac as far because full vac at a higher altitude is lower then at sea level. So if at sea level you pulled down to -27inHg to evaporate alcohol, at 4000 feet you will need alot less because ultimate vac is 25.8. If the ratio was the same youd need -23.32 inHg for the same evaporation rate at 4000 feet as at sea level.
This is off another chemistry site: Vapor Pressure Formula
Vapor Pressure Formula
When a liquid evaporates, the gaseous molecules created escape into the air. If the liquid is in a closed container, the gaseous molecules created will not escape but remain above the liquid. These evaporated particles created a pressure above the liquid, this is known as the vapor pressure.
So basically when you heat your liquid hot enough to where its vapor pressure is equal to or greater then the pressure pushing (atmospheric pressure) against it we call this “boiling”. We can basically use all this info to actually calculate the boiling point of a liquid at a certain atmosphere or reduced atmosphere.
This same site had some great info on calculating vapor pressures of solutions
Heres a quote from it
If a solid is dissolved into the liquid, a solution is created. The vapor pressure of the solution is lowered by the addition of the solute.
This makes sense as a solid does not have as much vapor pressure as a liquid. This is why when you have a ton of crude in the roto ball it takes more heat to get the same evaporation.
Vapor pressure and heat are directly related. If you increase heat you increase vapor pressure.
Crazy to think about, I fucking love applying science to cannabis though.
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So what’s the perfect vacuum to run a 50l rotovap for maximum efficiency and put less on the chiller?
Probably 20 -in hg so that ur alcohol boils at 50C, set bath to 60 or 70C and chiller at 0C
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“deltas runs under NO vac and runs the water at 90c”
where did you get this info? I thought they use a liquid ring vacuum pump
Read the manual show me where the vacuum pump is, i uploaded it above.
Wow thanks for looking that up, i had no idea it affected vacuum i thought it was just things open to atmosphere. Im still kinda confused/baffled that u cant achieve good vac even with a turbo or diffusion in the himalayans or in the rockys
Im at 100ft, so ive never noticed or had troubles with vac.
What happens when u go below sea level? Lets say in a deep bunker by the sea?
You are getting very confused here. The vacuum you pull with that diffusion pump is actually the same, whether you’re in the himalayans or the mariana trench. The issue is you’re comparing gauge pressure to absolute pressure.
A closed system with a certain mass of air in it has the same absolute pressure no matter where it is. And ethanol, in that system, will boil at the same temperature. The boiling point is dictated by the absolute pressure of the system.
On the other hand, what your vacuum gauge reads will be quite different. The gauge measures relative to the pressure outside of the system. At sea level, the absolute atmospheric pressure is 29.92 inHg. A perfect vacuum thus reads -29.92 inHg on the gauge.
At 10,000 feat, the absolute atmospheric pressure is 20.64 inHg. A perfect vacuum with read as -20.64 inHg on the gauge. If you had a dial that goes up to -29.92, the dial will only go down 2/3rds. It will LOOK like your vacuum is bad – but it is not, it is perfect. And in each of these two systems, inside the rotavap, the ethanol will boil at the same temperature. The particles only see the absolute pressure inside your closed system. They don’t care what the gauge says.
Inversely, if you go under the sea and run your rotavap (bear with me on the fantasy here), your gauge might read -1000 inHg. Boy, that’s some great vacuum! But the actual absolute pressure inside the flask is once again the same. You won’t be observing any difference in the boiling point.
The confusion here came about because people were comparing two different things without specifying. There’s absolute pressure (what your ethanol cares about) and relative pressure (what your pressure gauge cares about). At sea level, the two are equivalent, because the gauges were designed for use at sea level. At any other place they start to diverge, and it becomes important to pay attention to that max vacuum chart to see what your gauge ought to be reading.
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Thats a vacuum pump motor, if there pulling vac before the condensers then how are they moving the vapor through the condensers? Theres no other pump. Im 99%sure this is the pump they use to apply pressure to reduce the boiling point. Its not a vacuum pump its a recovery pump, they’re just using a vacuum pump motor.
Ive never heard of a vacuum pump that can move solvent, and that’s what theyre using this for.
I can’t speak to exactly what Delta is doing without a callout for what model that Baldor is, but a liquid ring pump would put vacuum on the evaporation side and give it an extra boost towards the condensing side easily. There’s also a variety of other “dry” hazardous location rated pumps like the Blackmer, Haskel and CMEPs that have no problem pumping solvents and are capable of pulling vacuum if they are sized correctly for the vessels and heating/cooling power they are attached between.
There’s also the physical properties of vapors that moves them from hot areas to cold ones, a simple pot still at atmospheric pressure has no problem pushing hot vapor towards the condenser and recondensing those vapors as long as whatever condenser is of suitable size.
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Yup, thought so… thanks for explaining the confusion thats going on. 
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