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meerkat last won the day on March 20

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About meerkat

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  1. I found some data on the web that gives the particle density of corn as 1.50 g/cm3. This converts to a displacement of 0.080 gallon per pound. Your example of 250 lbs would give a displacement of 250 x 0.080 = 20 gallons, so theoretically you would need to add 80 gallons of water to get to 100 gallons total. The data mentioned above points out that densities vary with moisture content etc, so you should take the value of 0.080 gall/lb as indicative only and experimental values will be best.
  2. @Still_HollerSorry to drag up such an old thread, but I was grappling with this recently and came upon this thread while searching for the answer. I believe I have found the answer in 27 CFR 30.71.. See also 30.72. § 30.71 Optional method for determination of proof for spirits containing solids of 400 milligrams or less per 100 milliliters. The proof of spirits shall be determined to the nearest tenth degree which shall be the proof used in determining the proof gallons and all fractional parts thereof to the nearest tenth proof gallon. The proof of spirits containing solids of 400 milligrams or less per 100 milliliters shall be determined by the use of a hydrometer and a thermometer in accordance with the provisions of § 30.23. However, notwithstanding the provisions of § 30.31, the proprietor may, at his option, add to the proof so determined the obscuration determined as prescribed in § 30.32.
  3. @ZimDist That depends on how clean you want to make it, and how much you can sell it for. In a liquor store you will probably find a 4 to 1 ratio between the most expensive and the cheapest vodkas. What is viable at the top end is not viable at the bottom end. I've read of expensive vodkas being filtered through beds of diamonds. Maybe that is viable in Zimbabwe? You certainly could put it in a batch still and take off some more heads at 95+ abv (ideally 96+). There are threads here that discuss the equipment required to achieve 190+ proof. It would require a bit of experimentation to get the optimum balance between the cost of losses (as additional heads taken off) and the improvement in quality. The neutral cane spirit that you can buy ex SA is made in continuous plants where there are multiple columns with multiple side take-offs in addition to the heads. I cannot see continuous distillation being financially viable at below 10,000 liters per day (probably more like 40 kl/day).
  4. The same convention is used in South Africa. There is very little grain-derived potable alcohol available here. It is all grape or sugar cane based. What we call cane spirit here is really a neutral rum. Locally vodka is made from the same cane-based neutral spirit. Each bottler has their own "magic" that converts cane to vodka, most of it involving treatment with activated carbon. I don't know how much of it is hype and how much is valid technology. Some very well-known international vodka brands are made in South Africa from cane spirit. If you want to make a very smooth vodka, you must start with a very smooth cane spirit. In my experience it is difficult to remove harshness from a spirit by any method other than distillation.
  5. @joshYPV Yes, it is ideal for that. As long as you know (or can measure) the sugar content of your honey you can treat it as syrup in the software. If you need some help in setting up the calculation send me an email using the support address listed in the software, with a typical proofing calculation and I will set it up for you.
  6. I was looking at the Hillbilly Stills calculator linked by @Thatch to try to understand why their numbers were so different from mine. The main difference between the calculations is that I had 2.5 %abv left in the still heel, but the Hillbilly calculation would give 0.5% in the heel. My calculation assumed that you were using a pot still without any trays or reflux, and then worked back from the 20 %abv ending strength in the parrot to get the heel strength. But then I calculated what strength you would get in the parrot at the start of the run and it would be impossible to get 82 %abv from a 8.5 %abv mash. I guess this means that you are using some trays and reflux in your still. This is one of the difficulties in designing a calculator - every still is slightly different. I can see that the Hillbilly calculator would be very useful, so I tried to understand what it is actually doing. It seems that it is based on the assumption that 95% of the alcohol in the original mash is recovered in the distillate. Because of the virtual impossibility of being able to model every possible still configuration, to be able to calculate the volume split between the distillate and the heel you need 4 bits of information. These are the volume and strength of the initial mash, and the strengths of the distillate and of the heel. The Hillbilly calculation asks for only the first 3 items and it calculates the heel strength internally by assuming that 95 % of the alcohol is recovered as distillate. If it is reasonable to be able to estimate the 4 items I have listed, it would be very easy to make a spreadsheet to calculate the quantity of distillate and remaining heel.
  7. @Georgeous Sorry, my bad. @Eud is correct. The 37.7 gallons are gallons of absolute alcohol and not proof gallons. But the conclusion remains the same. I calculated from theory and got 38.5 gallons of absolute, compared with your actual measurements of 37.7 gallons of absolute.
  8. No, what I was trying to say was that within the accuracy of your measurements and my theoretical calculations the results are effectively the same. I don't know how precise your 600 gallon and 100 gallon measurements were, but I suspect there would be some inaccuracy there. Certainly my theoretical calculation was not very accurate. For a start I totally ignored the shrinkage that occurs when alcohol and water concentrations change. I made a couple of simplifying assumptions to make the calculations easier and quicker. My gut feeling is the 37.7 proof gallons that you calculated is probably within 1 gallon of the true value.
  9. @Georgeous What you have achieved is very close to the theoretical numbers. The 51 gallons of alcohol you started with looks right. If you stripped until the spirit in the parrot was at 20 abv then (assuming no reflux was being used) the theoretical strength of the spirit in the still should have been 2.5 abv. Ignoring the shrinkage, if you took of 100 gallons of distillate there was 500 gallons left in the still at 2.5 abv. This would make 12.5 gallons of alcohol left in the still. If you started with 51 then the distillate should contain 51 - 12.5 = 38.5 which is very close to what you achieved. The reason there are no easy-to-use calculators for these calculations is that the calculations are simply too varied. You can get process simulators that are really aimed at the petrochemical industry, but would handle these calculations, but they are horrifically expensive - typically more than $100,000 and only the largest engineering contractors have them. And they have specialist engineers to drive them.
  10. @kleclerc77 The first rule of engineering: if it ain't broke, don't fix it. Don't drill holes if they are not needed. In my opinion, all gravity lines should be sloped. Many are not, but still operate successfully. Invoking rule 1 once more - if flow in a horizontal pipe is adequate, don't change it (but I am glad to hear that yours are sloped!). If the lines are big enough and sufficiently sloped then the vapor can rise against the flow of liquid and escape via the condenser. This could be why you do not experience the vapor locks that others have reported, and why you can leave the drill in the cupboard for now.
  11. @kleclerc77, See the sketch (Weep Hole.pdf) sent to @StonesRyan by Vendome in the thread
  12. I understand your nervousness. Do not drill anywhere into the pressure envelope (i.e kettle shell or nozzles protruding outside the kettle), but the pipe inside the kettle is quite safe to drill. I do not own a still so I cannot say I have done it to mine, but I have done similar things when consulting to others. Hopefully some real still owners can confirm that they have done this and it worked. There are two reasons why vapor could be making its way back to the kettle. The first is that there will be air in the column and return piping at start-up, and some of this this will be pushed back to the kettle by the draining liquid - the rest goes out via the condenser. The second reason is that if the drain outlet from the base of the column is not flooded, vapor can enter this line. This would be alcohol and water vapor and will condense with time, depending on the pipe sizes, flow rates and thermal insulation. Of course any air that is trapped never condenses and has to be flushed somehow. The hole in the elbow deals with both situations.
  13. Residual sugar levels, target alcohols, yeast tolerance etc are a whole different topic. I suggest you start a new thread for that. It's not something I can help much with.
  14. It would be best to check with Rudolph Research themselves, but this would be my interpretation of the numbers. 1 Refractometer Brix = 8.38. Pure water has a refractive index of 1.3330. If you add either sugar or alcohol to the water the refractive index will increase. The 8.38 is the apparent brix, assuming that there is only sugar (and water!) in the sample. There are an infinite number of combinations of alcohol and sugar concentrations that could give this apparent reading, but fortunately if you know the density as well as the RI you can calculate what the true brix is. This number (8.38) is pretty meaningless by itself, but is needed in combination with the density to get the true brix and ABV. 2 Brix Corrected for Alcohol = 4.79. Using the apparent brix of 8.38 from the previous step, together with the density of 1.003592 g/cm3, the true brix (and true ABV) can be calculated. This is the best (only) indication of how much sugar is left in the fermenter. 3 Brix = 1.39 Deg Brix. Unlike the refractive index where adding either alcohol or sugar increases the RI, the density of a solution is increased by adding sugar but decreased by adding alcohol. If you used an hydrometer calibrated for brix and put it in your sample it would indicate an apparent brix 1.39 and not the true brix of 4.79 determined above. The presence of the alcohol lowers the density and therefore the apparent brix. This number is also pretty meaningless in my opinion. I don't know why RR give so much detail on the brix but not on the ABV. The density meter and the refractometer will also give apparent ABV readings, but these seem to be ignored and they show only the corrected ABV.
  15. You need to be a lot more rigorous in stating your conditions, especially as it seems that you are not in the USA while most of the members here are from the USA and will potentially make incorrect assumptions for the information that you have not supplied. You say that you started with 37.5 litres of 96% NGS. At what temperature was the 37.5 litres measured? I suppose it is reasonable to assume the 96% is ABV, but if it is you need to tell us at what temperature the 96% ABV is measured. What is 40.5 kg lbs? Is the gin's 70% ABV a true measure at 8°C, or is it an apparent ABV measured at 8°C on an hydrometer with some other calibration temperature (which should be specified if it is), or is it 70% abv at some standard temperature but is currently stored at 8°C? Do you want to know what the bulk volume of the 70% abv gin is, or does your government want to know the litres of absolute alcohol in the gin or the "proof litres" (if there is a government that works in those units)? If you have not tried my AlcoDens software to solve your problem please have a look at it just from the point of view of seeing what information it asks for in order to perform the calculation. It is a bit of a pain to have to provide all that info, but unless you do you will only get an approximation of the answer.
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