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Sungla Distillery LLC posted a topic in EquipmentHi there, I am a newbie, both to this forum and to distillation in general. And I am about to set forth on one of the biggest ventures of my life: to build my own distillery from ground-up. I design things and my friend will do the metal works. My friend seems very sure of what he will be doing. But I am not. So I am here asking for your help! (Why from ground-up, you may ask. Well, a short answer is: I couldn't find any ready-built distilling equipment suitable for the place where we put our distillery.) I've just spent the last two months laboring on numbers and drawing, going from one equation to another and back. The whole process was much more convoluted than presented below as I didn't know much from the start. But here it is: 1. 500 liter still (132 gallons). This is the starting point. 2. It requires 115K BTU to bring 500 liters of 60/40 mixture of water and ethanol (40% abv) to boiling point and 755K BTU to vaporize them ALL (latent heat). (I don’t do strip run, only still run with 40abv spirit). Hence, a total of 870000 BTU is required to vaporize all 500 liters of this mixture. 3. One distillation run will take 8 hours (I just pick a number to fit into a day of work). Hence, a steam source of 109K BTUh (BTU in one hour) is needed. 4. The steam will come from a wood/coal-fired steam boiler. I did a search on “heat content of wood” and pick this number, 12MMBTU/cord (3.625m3). From there, it would need 0.03 m3 (1 ft3) of wood to generate 109K BTU. The firebox, therefore, must be big enough to burn, at least, this much wood in one hour. This is the easiest requirement ? 5. I design a firebox, and blower and secondary combustion chamber, etc…, to burn three times that much, i.e: burning 0.9 m3 (3 ft3) of wood in one hour to generate 327K BTUh. Assume that only 70%, or 229K BTUh, of this heat acctually goes into making steam. 6. Latent heat of water is 2141 BTU/kg. With 229K BTU, the boiler can generate 107kg steam in 1 hour, equivalent to 6.8 BHP (1 boiler horse power = 15.65 kg/h of steam). Now come the confusing parts: 7. Jason Funk at Hughes Machinery states in his Basic Boiler presentation that for vertical firetube boilers, like the one I am building, every BHP needs 3 ft2 of heating surface. So my boiler would need 6.8 BHP x 3 ft2/BHP = 20.4 ft2, or 1.9 m2, of heating surface. I’ll add another 50%, bring the total of heating surface to 2.85 m2, to be on the safe side. 8. I omitted the actual calculation with the heat transfer equations and went with an estimation from CheCalc.com and the Titan Metal Fabrication websites to derive the length and surface for the immersion coil in the still. If all 500 liters in the still are water, hence 489 kg, then I would need 0.78 m2 of cooling surface to raise the water temperature from 20C to boiling point in 1 hour. I plan to use 22.1mm diameter copper tube and that brings me to a total 11.3 m of tubes. I’ll make it 20 m, to be safe again. 9. Last part: Condensing tubes. I plan to use the same amount of tubes that are in the still, i.e.: 20 m2 of 22.1mm diameter copper tube. As said, I have gone back and forth countless times between these numbers, checked them against multiple formulas and/or website (which I am glad to provide if asked). At this point, I am very much comfortable with them. But again, I have never done this before. There is still a lingering doubt in my mind, of course. I will (forever) be grateful to anyone who has the patience and/or knowledge to examine these numbers for me. If they are indeed bogus numbers, I really don't want to spend a couple grand on them before knowing... Thank you! Khoi