Distilling ALCOHOL With Our New Reflux Still!

Hello, today we are going to make a video about di

still

ation equipment or

still

s. A couple of years ago we made a video on a very simple lab distillation, going over some of the principles and using that copper still to produce our banana brandy and whiskey. videos, so if you're interested in the topic, you might want to check out some of those videos today. What we are going to do is cover this process, but we will take it much further. To begin with, distillation is a separation process, but it is not a discrete process, in other words, if you take two containers of water and

alcohol

, you put them in a flask, you boil it, and you condense it in one container if you boil it all. in this container, obviously, everything that is here would end up here, of course, however, it is not a discrete process where you only get the

alcohol

at the beginning and then you only get the water at the end; there is an overlap, so every drop that ends up in that receptacle from the first to the last there will be some of everything that is present here, what causes the separation is time.

At the beginning we tend to get more volatiles and at the end we tend to get more water. less volatile material and what determines that type of separation and the superposition of those two curves are two principles: one is the absolute vapor pressure of the liquids above the pure compounds. Water has a very low vapor pressure compared to alcohol, it is about only one third of the vapor pressure of alcohol, the reason is that water molecules are very sticky, they have a very high van der waals, they have a very high intermolecular attraction, that's why it has a high boiling point, alcohol not so much and when you add alcohol to the What happens with water is that the alcohol molecules interfere or essentially obscure the water molecules from each other, which limits the amount of intermolecular attraction and therefore lowering its boiling point makes it possible for it to vaporize more easily.

Similarly, alcohol is stickier to water molecules than it would be. be for other alcohol molecules by effectively raising their boiling point, so the boiling point of the mixed liquid is somewhere in between the boiling point of the two pure liquids and the percentage of the vapors that are above here as well. They depend not only on absolute vapor pressures. but in the percentages of the liquid here, what happens is that when it boils initially we will get mainly alcohol and a little bit of water, but as the alcohol is extracted and the concentration of water increases here, the boiling point increases and the percentages. of the two components in the flask over the vapor also changes and eventually we begin to produce more and more water and less and less alcohol.

Now the way we get the actual separation is by simply stopping the process if we boil off about half of this. and we end up with about half of the result in the container here, we will have more water and more alcohol left here, if what we do is take what is left here and throw it away, take what we have produced in the receptacle, put it back here and do it again. We will get a higher concentration of alcohol because we have a higher concentration of alcohol in the mixture. There will be a higher percentage of alcohol in the vapor and we can do that. this over and over if we do this once we could get maybe 65 70 percent alcohol here if we stop halfway if we do it a second time we could get 80 percent do it a third time 82 a fourth time 82 and a half and asymptotically we will get close to a pure alcohol and we will never get there, but we will get close to 100 percent pure alcohol now, that is effectively what is being done when they use these large stills, the Scottish brewers will use huge versions of these stills or simple stills to do it. whiskey distillation, the reason we use this type of system and prefer this type of relatively modest separation is because we don't want to just produce a reagent grade chemical from here, we want to produce a flavored beverage so that the esters and We want some of the aldehydes that are present in the pre-distillate to pass through the system, so as a result of using a relatively moderate level of separation, we can still retain many of the flavors, but now we concentrate the alcohol.

The design of this It's pretty obvious that you have a pot and then you have a bell or an onion lid that captures the steam here and then directs it through this copper tube to a container here where you can put municipal water or river water wink wink and cool the coil that is mounted inside the chamber which cools the coil, condenses the vapor and allows you to collect the output now if you want a little bit better separation what they will sometimes do like I just described is they will they will take maybe half of the residual here throw it away or save it set it aside take the product from the first distillation put it back here again and repeat the process increasing the separation decreasing some of the stronger flavors and sometimes they do this two or three times to get The type of separation you want.

The problem with this type of discrete process is that it wastes material and takes a long time to clean and refill. It would be nice if you could do this continuously or continuously. process and that is the purpose of what is called a

reflux

column or vagro. What this glass blower has done is pushed little dimples into this long column here that don't penetrate but increase the inner and outer surface area, the outer surface area so that we have more convective cooling and the surface area. internal so that we have more interaction of the vapor and the glass, as well as causing turbulence to cause good mixing of the vapor, what makes this interesting is that when you boil the liquid down here, as we are going to do in just a moment , the steam coming out of here enters this tube first and because the tube is further from the heat source, it is a little bit colder, so the steam coming in here will selectively condense some of the water molecules a little more than the alcohol molecules because they have a lower vapor pressure, a higher boiling point and as they drip down here the slightly enriched alcohol vapor will rise to the next level, here again it will preferentially condense the water that will drip downwards and in increasing concentrations. of alcohol vapor will rise through the column until it reaches the top, eventually when it reaches this angled bend here, all the vapor is directed through the condenser where all the vapor cools, turns back into a liquid, and It is then placed in the receptacle.

Over here, this type of process is much more efficient and time-saving and can increase the concentration of the final product in a single pass up to perhaps 85 percent, so it saves a lot of time. You can overcome this and produce even greater concentration by doing so. two things: one, you can slow down the heating, lower the heater temperature a little bit until you get just a little bit of steam over here, as a result, you tend to compress these

reflux

cycles and more cycles occur here and you get separation higher, alternatively you can simply stack a bunch of these columns on top of each other, giving you much more room for cooling and a greater differential from one side to the other, again improving the separation process.

The problem with that is number one. In the first case, you have to slow down and it can take six hours to do the separation. The problem in the second case is that you have a very unwieldy tower that you have to deal with. Now, what I'm going to do. What I do is I fill this out and I'll show you how it works. Actually, let's run this. I'll show you an interesting tool that can be used to calibrate the type. of the product that you are producing now this is isopropyl alcohol and I am going to fill this column to the top line and I am going to use what is called a hydrometer, this is a calibrated float that when it sits in this liquid it will be supported according to the density and because of that the alcohol is not very dense, this sinks much lower into this container before it is finally supported and you can see that it is near the top where the numbers represent 100 alcohol 90 alcohol 80 alcohol is very Down here, this is 91 percent isopropyl, so it's pretty close.

The fact is that it is calibrated for a specific temperature of 20 degrees Celsius and also for ethyl alcohol, so this will not be perfectly accurate, but you get the idea if I were to take. This same setup and we're going to put this in the boiler and instead of using alcohol, what we're going to do is fill this with water up to the same mark. This sounds very scientific, doesn't it? Now when I put the float here because of the higher density of the water, it doesn't have to go as deep before it floats and you can see this sticks up here, around zero percent alcohol, so if we now repeat this pour . this here and then just to show you how you can use this kind of to calibrate the amount of alcohol, we're going to fill this halfway with the alcohol and then we'll fill it the rest of the way with the water and then when I put the float in here , you'll see that it floats in an intermediate position because of the intermediate density here, so it's a useful tool to know what you're doing while you're doing the distillation process now I'm going to pour these liquids here and the rest as well and then, like with a smooth glass flask like this you can get pretty big bubbles, I'm just going to put a small stirring rod in there. here to help break up the bubbles makes it a little less likely to overflow turn this on and then we'll turn on some heat and when it gets up to temperature we'll see this reflux process develop so we'll take a few minutes and let it This is heated up so, as you can see, the level of this thing is increasing very quickly.

Notice the temperature here 18.7, the steam has not arrived here yet. Observe what happens as soon as the steam reaches this point. Over here, bam, watch the temperatures skyrocket as the vapor starts to fill up here and you can see the dripping that happens down here with all these reflux loops as the alcohol concentrates. Now, in about a minute, we're going to get enough. There is condensation here that will begin to fill the receptacle. Here you can see that the droplets are starting to form. Well, let me show you the effectiveness of the distillation process. Take this off and collect some of the drops we're going to put it on. our cylinder and remember that it was previously supported halfway when we put the hydrometer here, now we'll see what happens and you can see how it floats much deeper near the 190 test, so clearly this works now, one of the limitations here.

Obviously, we can't get the separation as high as we would like simply because the height of this column is limited and the amount of differential we have here is limited, so if we want to take this further without it being a hassle, we introduce the Next tool is called active reflux, so it is a 60 liter active reflux. Still, we get it from a company called Brew House in Texas. We'll put a link in the description below. There is another company called Still Dragon that makes even higher-end products. stills that can cost up to hundreds of thousands of dollars and thousands of liters of product capacity, but they all work on the same basic principle.

The 60 liter container here, which has the maximum capacity, should only be used up to about 40 liters because you will always want space above any distillation for bubbling and churning to occur, so you don't force the pre-distillate into your column of reflux, so it probably has a capacity of 40 liters. If you look down you'll see these snap on or spring loaded Band Heaters that are mounted on the side here each of these are 1500 watts and what they do is they provide heat on the side walls and the reason why that is Important is anyone who has experience making something like custard or boiling anything. that has particles, the particles tend to settle to the bottom and if all the heat is coming from those particles, whether from a flame or a heater at the bottom, there is a greater chance of burning the material here and adding flavors, so By putting the heat on the side walls where the particles don't tend to settle and then also extending the surface area much larger so that we don't have as much local extreme heating, you minimize the chance of burning as you go this way.

This is the reflux column and we'll get into this in a little more detail later because it works on a different principle than the growth column I showed you before. What makes this still substantially different is that this is an active reflux condenser or a baffle and what this does is it cools the hot vapors that pass in the first reflux cycle through this relatively short column and effectively what What it does is bend the reflux backwards because what it does is condense the hot vapors and sends them back. for another pass through the reflux column and being able to adjust withprecision with one of these valves the amount of heat that is extracted here, you can turn this off and effectively eliminate the reflux condenser property and you will have a moderate reflux tower here or you can turn this up to maximum for maximum cooling and effectively extract all the heat that you originally posted here and create almost an infinite loop of reflow processes and you will essentially get no output now which might seem useless but there is an app for that. and I'll get into that in just a second in any case, once you get past the reflux condenser, you get to a reducing point connection here that has the thermometer that allows us to measure the temperatures of the vapor coming out above the condenser, then the Vapors are directed back down through the true distillation condenser and this is where all the heat is removed, all the vapors are converted back into liquid and the liquid is poured out here.

What we do is connect a device called a parrot to this. I guess it's because it looks like a parrot and the way this works is that the liquid flows down through this pipe. and it runs into the internal pipe up here and what this pipe allows you to do is that as the fluid flows here and into this conical receptacle and then comes out through the spout here, you end up with a level of liquid in a column which is very similar to the cylinder we use to measure the specific gravity of the liquid, so if you take this hydrometer that I used before and float it inside this column, you can do a real-time continuous measurement of the density of the liquid coming out .

From here, instead of having to constantly cut samples and remeasure this manually, it gives you good feedback during the process, so it's a nice feature to have now. Another interesting feature of these high end stills is what is called a T connector if you see this flange on the end of the pipe here it has a small indentation on the top surface that matches a indentation on the bottom surface of the end receiver here this thin silicone gasket then fits inside this little slot and when this is placed on the end of this connector here what this T clamp does is because it looks like there's a rectangular slot inside here that's actually tapered already that these two flanges meet this taper connector as you push down it tends to bring the two components together making it lock very securely and then when you hold it over here like this and then you put the T connector here and you tighten it, not only do you get a great seal here, but you also get a very mechanically strong connection, so this holds this in a solid position, this is usually used in a lot of vacuum systems because it's very effective and as you can see , this same type of T-clamp is used throughout the still, from the top to the end. bottom and that allows you to disassemble the entire unit to clean it, but it provides a very good seal and mechanical support during the distillation process now, although we have about 3000 watts on the bottom of this thing, it still takes us about half an hour. to bring the 30 liters of liquid that I have here to close to boiling point, so let me turn on the heaters and we'll heat this up and then we'll get to the really interesting parts of this.

So as you can see, we've had this running for about half an hour and we're starting to build up some liquid here and we've got these plates charging with liquid and doing some reflux and the vapor is starting to move up. With condensers I don't want to lose any vapor, so what I want to talk to you about now is that the distillation of the cooling system obviously depends on heat and a lot of people focus on heat, but cooling is very important because obviously we have to condense those vapors into a product and typically what you'll do in a system like this is you'll connect the cooling system to a municipal supply or well water, or you can use a very large radiator like the hacked one. computer system radiator cooling system we use for our lab bench unit.

The problem with that type of cooling source is that it can vary in temperature depending on the air temperature in the room with the radiator or the time of year it is connected. to a municipal supply by varying the water temperature we vary the cooling of the water even though it has a continuous flow of liquid and because of the importance of adjusting the reflux condenser precisely to get just the right amount of fold from our reflux cycles and some passes . a vapor, if the temperatures vary throughout the process, you will be chasing the valve settings on the reflux condenser and will be less efficient in terms of capturing the liquid, which occurred to me and which I have never seen.

Does anyone else think this is a smart thing to do? I took advantage of the fact that we have this chest freezer here and we'll get a photo of this inside, but what this chest freezer consists of is an aluminum interior liner with the cooling coils. and I took some flex seal and sprayed it on the joints between the aluminum turning it into an airtight container and then I filled it with about 110 liters of fresh water and turned on the freezer a couple of days ago and what happens is it starts to freezing the water along the cold surfaces inside the chamber and after about two days I have frozen about half the water so I have ice around the sides and I have an internal area in the Here the middle contains only water.

The nice thing about this is that as the heat is dumped from this unit into the cooling system, the temperature of the water does not change, we simply melt the ice and retain exactly zero degrees Celsius of water continuously during the process and with about half of it. of the water here frozen and half water, we have enough cooling sink in this unit that, even though the unit is now turned off, we could run it for about six hours, about three times longer than we would during any normal distillation with just the cooling water that is here so as not to lose too much product in terms of steam.

I'm going to plug this in and show you how it works in real life, so we have our opinion here, which is this tube. and we're going to hook this up to a pond or aquarium pump and then we're just going to sink the pump into this center section where the water is and then we're going to take the two outlet tubes from the reflux and the main condenser and we're just going to drop them in. If we put them in there, we're going to plug this in and send the water through the system like this.

In the meantime, what I'd like to talk to you about is that they're kind of interesting, it's called a bubble dish and it's a copper disc with these little crenellated lids that are mounted on top of similar little pieces that are braised on the surface here. and the way this works is quite interesting on the bottom, the steam can pass through these holes and rise through the top surface of this plate, once the steam surrounds the top of this inner cylinder, it What happens is that the steam is forced down through the space between the lid and between these little grainy openings at the bottom of each of these lids and it will bubble as it does so, the bubbling will allow some of the vapor to be produced. cooling process and it will start to develop a layer of liquid, as you can see here on top of each of these plates, that liquid will continue to rise until it reaches the top of this little bit here and then pour it into a lid with a mirror on the lower.

Here this cap also has a bolt on the bottom and allows the liquid to fill this cap until it reaches these little holes here where the liquid starts to fall. What's so elegant about this? It is a kind of one-way valve for liquid and gas. Because of the gas coming out of here, the liquid cannot go up to these lids and because of the layer of liquid here, the vapor cannot go up here, so the vapor can go up through these holes and the liquid can go down through these holes and then each of these bubble plates will develop a layer of liquid over them which actually achieves the reflux action in a liquid phase instead of a solid one in In the vegro column we depend on the surface area here to provide cooling of the vapor and extraction of water molecules to concentrate the alcohol.

In this case, where the real reflux occurs is on the inner walls of each of the bubbles like this cooler. The liquid here sees this hotter vapor, it will draw from those bubbles a small amount of that water that accumulates in this layer of liquid here, so the reflux or concentration actually occurs in the bubble, not on the surface of the glass . Now you can see. This is continually moving up here and you can see the drip coming from each of these little pieces here as the vapor rises into the reflux condenser. You can see that the temperature up here right now is approximately 78.8 degrees.

We don't have enough steam here right now to have warmed up the thermometer and therefore we don't get any results here. Another thing I want to mention about this bubble plate is the fact that you can tell, unlike the entire structure here, which is constructed of stainless steel, it is made of copper and there is a reason why when you ferment any type of grain or any type of fruit, you will produce a very small amount of hydrogen sulfide and hydrogen sulfide is an interesting thing if Have you ever been in a chemistry lab and smell that stinky smell that smells so bad that it smells like a rotten egg that is? hydrogen sulfide?

Hydrogen sulfide is almost as toxic as hydrogen cyanide and in very, very small amounts will create a kind of unpleasant rotten smell or taste that will permeate the final product and due to the fact that it is a nerve toxin in very concentrations low, you can smell it, but when the concentrations get high enough, it will actually anesthetize your olfactory nerves and you won't be able to smell. As long as it smells bad, it's safe, but once you can't smell it anymore that's when it becomes dangerous. That doesn't really apply here, but it's an interesting material and the way that copper interacts with this is that hydrogen sulfide is absorbed by This is the copper, it forms copper sulfate on the surface and hydrogen gas is released, so which the copper will actually convert the hydrogen sulfide into something that sticks to the copper plate and eliminates that taste, so even when you use a stainless steel, you'll still do that.

I always want to have some copper in intimate contact with that vapor to be able to absorb the hydrogen sulfide, so when you have a still that doesn't claim to have a complex reflux column like this, you can make it with copper, which is why they use copper in the stills and also, if you don't have an easy way to add the copper in a pipe, you can put a copper screen or a copper tube inside the column that has contact with the vapor to remove the hydrogen sulfide now. As this continues to boil, we can see that the temperature went from about 78 degrees to about 84 degrees, as this continually filters the water.

This water coming out of here now is pretty hot, so this unit up here is doing some reflux cycles, but not very much. a lot and when this temperature rises to about 150, which will happen in about two or three minutes, we'll start to see some output here. Now you can see the temperature is rising pretty quickly, we're at about 141 degrees Fahrenheit 160. Now you can see the temperature is rising, it's going up to 162 degrees Fahrenheit and you can see we're starting to drip down here, so we're getting output , so I'm going to close this valve and Now we're going to start filling this internal chamber here and look for an overflow to occur up here where we can then do our specific gravity measurement.

This will take a minute or two, so if you see here, we have a temperature of 170.0 degrees Fahrenheit and If you look here, you will start to see the liquid reach the top and start to overflow into this conical section here and then soon it will start to spill through the faucet. So I can take advantage of that convenient cylinder and I'll plug in my hydrometer and you can see that what we're looking at now is about 180 in terms of testing. Now if we reduce this, we can obviously get higher concentrations. If we add another bubble plate, we can obviously get a higher concentration.

In other words, or if we put our uh def leg meter or reflux condenser back to a slightly more aggressive reflux, we can increase the concentration, but over time this will continually increase as more and more water is added to the final exit. The concentration of this here, like I said, is about 180 degrees and the good thing about this is that it's freezing cold because we're using zero degree water to cool it. This is frozen, so the product that comes out of here is frozen. As a result, instead of being warm or at room temperature, theVery volatile alcohol evaporates into the air when using super cold water to cool.

It is a big advantage. Another advantage of this type of system is the fact that it can be modified. for different types of applications, for example, let's say we didn't want super high performance filtration. What we wanted to do here is have more of a pot set up. What you can do is turn off the reflux condenser so that we're not doubling the reflux cycles as many times and then you can take an insulator and wrap it around the reflux column like this, essentially converting this from a reflux column to a system. With complicated plumbing, the steam does not have the opportunity to reflux and therefore we have created a still from a reflux column, very easy to make with a simple piece of insulation.

The other thing you can potentially do is if we change this to a high input for the reflux condenser and basically fold everything back. Time and time again we can take advantage of a process called alcohol extraction when people make flavored vodkas or gin, what they do is take the hot vapors of the alcohol and extract the aroma and flavors of the botanicals that can be placed in this system with hot steam what you do is you get a segment of pipe that looks a lot like the reflux condenser here in diameter and length and it can be inserted here by opening this space and placing it here or it can be put post condenser here and expand.

This up here what What it does is if you put it up here, the hot alcohol vapor will pass through this segment which has a perforated stainless steel plate on the bottom and it allows you to put botanicals in that container, so if you're making gin I would use berries of juniper and a little bit of cardamom and depending on your recipe, maybe lemon peel with allspice and all of those flavors will be extracted and sent into your final product. If, for example, you want to make a flavored vodka, you could do the same if you want even more powerful extraction and use fewer botanicals, one of the things you can do is place the filtration system or gin basket, such as It's called down here, and it will reflux hot alcohol vapors over and over and over again through the same botanicals, making it more efficient and at the same time extracting less volatile substances and making a stronger extraction.

There are many things you can do with this simple still without modifying much from the way it is set up now. That's basically how it works and it's pretty cool and pretty interesting and we're going to do a lot of experiments with this in the next video. What we will do is show you how to make flavored rum. so if you like the type of things we are doing in these videos please subscribe we are growing like crazy and our next goal is one million subscribers and we would really appreciate it because the bigger we get the more money we get. from youtube to be able to finance the type of equipment we are using for these videos if anything I have covered here is not clear or you want more details put your questions in the comments section because I read them all and I try to answer many questions, also, It also gives us a lot of ideas for new videos and things we might want to cover in a little more detail, so I'll have a lot of fun.

I will have so much fun. what are we doing here and please stay safe have a great afternoon and we'll see you soon