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Gin Basket GB4 - Minimum wattage for fast flow through 3/4" holes?

edited January 2014 in Usage

If we need spacers with a small hole to raise vapor speed, it seems logical that there would be a minimum wattage that would produce this flow.

Comments

  • Hi @Rocky_Creek,
    A professional gin maker in Australia helped with the design of the GB4 and he told me several times that the higher the vapor speed the better. He also mentioned that the small (to him) equipment that we use was not going to get the vapor speeds needed for efficient extraction of the botanicals.
    He did not give specifics of necessary vapor speeds but he did insist that the 2" triclamp ports were way to big.
    I simply could not hang the weight of the GB4 plus the extra piping and condenser from 3/4" pipe so we developed the choke washer to be able to use the more robust 2" fittings.

    The Carter-Head style SD GB4 is a small scale application, compared to the few remaining massive industrial units still in operation, and it is new to everyone because it's never been available to any of us before.
    I've run mine at 2kW and 4kW so far and I'd have to agree that more power/vapor speed is definitely better. I haven't tried it yet with the 6.6kW that is recently available to me but I'd bet it would work even better.

    Really hoping that folks that have already purchased a GB4 will help add to the empirical evidence or run data before the next production run.

  • I can understand his comments. The principle used here is that the volatile components in the botanicals are EVAPOURATED by the hot vapour. This is NOT solvent extraction. In this application you want high speed hot vapour. The other typical method you see, condenses the vapour on contact with the botanicals, and then drips through them. This does involve some solvent extraction but less intensively than with the botanicals in the boiler.

  • Are the choke washers to be fitted to inlet and outlet?

  • That's a really good question and I just don't know.
    I included 2 choke washers for people to try but have not received any feedback yet.
    My logic was that having one before AND after the GB4 housing would help to increase the vapor speed inside the housing as the vapor is being forced through the smaller opening instead of being allowed to expand to the size of the 2" pipe. My logic could be flawed so someone Please provide real life feedback on the choke washers.

    We will be working on the next production of 50 GH4 kits soon and would like to include any useful modifications.

  • Have not had time Lloyd but once set back and have time for runnin that is next! work out of town for the last 4 months makes it tough to do anything but my job and OH yea take of the house and wife!

    It is what you make it!

  • There is one thing that I am not sure that I get about the choke washers.

    The vapor flow rate needs to be the same everywhere in the column and is equal to whatever is produced by the boiler. The vapor speed at any given point in the column is given by the vapor flow rate divided by the effective cross section area at that point . Now, while the choke washers do increase the vapor speed at the washers postition, I fail to understand how they would increase the speed between the washers, at the basket position (unless they create significant back pressure in the column, which i doubt). Vapor speed at basket position should be increased by the space taken by the aromatics.

  • Agreed.

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  • On the few example commercial sized Carter-Head examples that I've seen a rather large basket chamber was fed by a very small pipe. The example that comes to mind has a chamber that appears to be 1' diameter and about 2' tall and is fed by a 3/4" pipe coming from a large still.
    Everything was hard piped together but to make it modular I just couldn't hang that much weight from 3/4" TC piping and went with 2" TC for strength. Hoping the choke washer would help to increase vapor velocity through the gin basket yet if they are not useful they can be eliminated from the next production run.
    I do not fully understand the dynamics of vapor pressure although the gin basket housing does resemble an expansion chamber/dryer on an air conditioning or compressor unit.

    My understanding is that you need to drive the vapor very fast through the botanicals for effective extraction and whether the choke washer(s) help or not is still an unanswered question. Any feedback from actual runs would be useful.

  • Agree with @BenStiller One would think that if you wanted fast vapor speed through the botanicals, you want a small cross-section gin basket... this is not the case, so I suspect that the small pipe is for economics of construction or heat loss... much like the 2" connecting pipes on the Kothe with a ~16" column that I posted..

  • I would have thought that once you placed a restrictor in your system aka the washer with a 1" hole that it would restrict all your flow to the max flow pressure of the washer. But then when you star talking flow rates of air and steam its a hole new game. All you would need to do is have your boiler temp one degree higher then the other bloke and you would have a different out come. Most of you probably all ready know that with water to work out your max volume in a pipe you x the pipe by it self. So 1" x 1" gives a flow volume of 1. 2" x 2" gives us a volume of 4. Lets remember that we can not compress water. Because we are not running our systems under pressure I dout we would see any major changes with 1" and 2". This would be complicated even more when you place your botanicals in. I personally think that we would not see any significant changes between the 2 size pipes. Most of us are going to be restricted by how much heat we can put in to our boilers. So I think you made the right choice with the 2" pipe.

    One question I have dose any one know what the working pressure of our stills are ??

  • edited February 2014

    Well said and I agree with your line of thinkin Drunkas,as far as pressure do not know,will find out soon! my new boiler has a port for a pressure gauge,when it arrives will see! The gauge not the boiler!

    It is what you make it!

  • @Drunkas said: One question I have dose any one know what the working pressure of our stills are ??

    I installed a pressure gauge on my boiler and no matter how I configure the column, and running all three 2400 watt elements full on, it does not budge off of zero. The scale is 0 to 10 bar so that may be too 'strong'. 0 to 1 bar may have been a better choice.
    I'd imagine the pressure in the boiler has more to do with the back-pressure created by the vapor being pushed through the fluid bed on the plates but it's so slight that I cannot see any movement at all of the needle on the gauge.

    You guys are talking me into eliminating the choke washer because if it does not serve a function then it just adds confusion. We have enough GB4s in users hands now (almost 50) and hopefully we get more insight from them before the next production run.

  • edited February 2014

    It's the head of liquid you are holding up, so if you have 4 plates with 1/2"of head on each plate you have 2" of head pressure.

    Then you have to take into account the height of the head over sea level, it's complicated and that's why they have engineers when it's important, but the simply answer is 2/10ths of fuck all.

    The Engineering ToolBox: Water - Pressure and Head

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  • edited February 2014

    @punkin said: but the simply answer is 2/10ths of fuck all.

    The Engineering ToolBox: Water - Pressure and Head

    Well said professor @punkin.

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  • edited February 2014

    I like the way you talk @punkin. 2/10ths of fuck all, is about what I was thinking. One thing I must point out to you all is I have only ever used a pot still so I am not familiar with the way these other stills work. I am just talking from my own knowledge of working with other machines. @Lloyd I have watched the YouTube video few times now and my question is how important is it to have the liquid in the bottom of the GB. If its not important then you could probably take out the washers.

  • The liquid in the bottom of the GB housing is from passive reflux and is really not wanted - although I have heard it mentioned that the liquid is tasty enough not to waste it.
    Once the housing gets up to operating temperature there is very little of that juice produced.

  • edited February 2014

    Ow and Lloyd 1 bar= about 14 psi 10 bar is about 145 psi so 0 to 1 bar is probably the pressure gauge you want and the GB is on my list of products that I want to purchase down the track. Looks like a very nice product made well like all the current gear I have from SD.

  • To some extent you can exploit mass and momentum. This would create a plume with more velocity. A washer as an orifice creates a very short plume that rapidly trades velocity and pressure drop. If you have a pipe with some length at the smaller diameter you have more mass at a higher velocity that extends the plume further into the basket. Beyond the plume, cross section of the flow and pressure (head) wins(this case loses) out. That is, with the washer most of the high velocity is lost at a very short distance from the washer, a simple pressure drop after the washer.

  • That's the best explanation I received so far @DeBluesDoctor. Thanks!

  • @DeBluesDoctor How would a 2" TC pipe with only an opening of a 3/4" pipe through the centre of it (both ends blocked similar to a product condenser/dephlegm) work?

    And would this "Vapour Accelerator" need to be twice as long as the Gin Basket to be effective? It should create more turbulence too

  • I think that maybe a venturi (carburetor) might be an interesting thesis project for some Phd-bound distiller, but for us mere mortals, the effect of the basket cross-section vs vapor mass flow rate (column diameter... well column area times vapor speed) would be of much better concern... great, now I have the measurement of vapor speed through my head... great, thanks guys, another project!

    basically, I hope it seems logical that what I am saying is that it seems fair that a 2" column using a GB4 could run much harder (than normally operated) than a 4" column when pushing neutral.. and a 8" column would have to go much, much slower than normal... the washer just creates a minor bottleneck and a small area where vapor speed is very rapid, and unless it is a 'nozzle' aimed at the botanicals, or the aforementioned venturi, it will not have much effect..

  • so, who wants to make a mass air flow meter for a column?

  • edited February 2014

    @Lloyd, just to refocus things.

    The important point in this is the vapour TEMPERATURE. All this issue about vapour speed, and small diameter vapour inlets is to ensure that the botanicals are hot. It is mostly (in this application) a question of the residence time of the vapour in the chamber. The vapour needs to pass through quick enough that it does not cool down too much.

    If the temperature drops too low the volatiles will not evaporate. The vapour is just carrying them along the vapour path.

  • @Philter said: DeBluesDoctor How would a 2" TC pipe with only an opening of a 3/4" pipe through the centre of it (both ends blocked similar to a product condenser/dephlegm) work?

    And would this "Vapour Accelerator" need to be twice as long as the Gin Basket to be effective? It should create more turbulence too

    The idea is that anytime you have a flowing vapor that goes from a larger cross section to a smaller cross section you have acceleration. The difference is when you get some length of pipe at this reduced cross section you develop some mass flow at the higher velocity when that gets to an aperture of larger diameter it wants to maintain that velocity for a longer travel distance away from the aperture. Even small jets are jets, they all dissipate that velocity over some distance.

    There are a couple of ways to approach this problem, one computer modeling the other is experimentation. I have been wanting to get a Gin Basket so maybe I can hurry that along and do some flow experiments and make some more accurate suggestions.

    Yep, I'm a physicist......

  • These are fantastic answers concerning the GB4.

    Seems like there are endless possibilities when you take into account vapour flow rate, temperature and the many botanicals available.

    I wish I had some spare Neutral to experiment with my GB4.....

  • @Myles said: Lloyd, just to refocus things.

    The important point in this is the vapour TEMPERATURE. All this issue about vapour speed, and small diameter vapour inlets is to ensure that the botanicals are hot. It is mostly (in this application) a question of the residence time of the vapour in the chamber. The vapour needs to pass through quick enough that it does not cool down too much.

    If the temperature drops too low the volatiles will not evaporate. The vapour is just carrying them along the vapour path.

    Good point. Flowing vapors experience a temperature drop when going through an expansion. It's a WORK function, temperature lost. At these temperatures, pressures and flow rates, the numbers are small but not zero. Like a bubble plate, small temp differentials, but effective none-the-less. You guys have stimulated my interest to know just what is going on in the GB4. Interesting physics problem, not in the next few weeks, but maybe over the spring and summer I will run some experiments and hope I can contribute and post something useful. Cheers.

  • For any who may want to visualize flow, simple threads strategically placed for observation are sufficient. Assuming view port allows observation. We don't need specific mass flows just to understand the general behavior of flow and turbulence. Some very interesting things could be done with a modified crystal column in this regard. The behavior of the area in and around the basket is what intrigues me.

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