Jump to content

stevea

Members
  • Content Count

    111
  • Joined

Community Reputation

3 Neutral

About stevea

  • Rank
    Active Contributor

Profile Information

  • Gender
    Male
  • Location
    Ohio

Recent Profile Visitors

870 profile views
  1. I've see that study before, and it's a bit hard to interpret WHY copper in the wash condenser and the spirit pot have the most impact. The latter part of pg 110 says ... << When used for the first time, the laboratory scale copper stills produced a spirit with a relatively sulphury and meaty aroma. Several repeat distillations were required prior to the start of this experiment to reduce this aroma suggesting that some corrosion of the copper may have been required in order to activate it. The actual mechanism of sulphur compound removal, however, remains to be elucidated.>> Copper has two oxidation states, and I might *suspect* Copper(I) oxide (Cu2.O) is the more likely hero of the story, can't say. An acid cleaning would eliminate the Cu2O and perhaps make the still ineffective of sulfur removal. The paper blames Dimethyl trisulfide (DMTS) as the main problem. This chem is detectable & obnoxious at parts per trillion! It's not very volatile, but a little goes a long way. Dimthyl Sulfide & sulfoxide are also present in large amounts, but are less problematic. There is an old winemaking trick of adding copper or a little copper sulfate to get rid of hydrogen sulfide (H2S) in wine. Copper sulfate can (w/ free chloride ions) remove DMSO. I wonder if copper sulfate in the wash might eliminate the DMTS or precursors. === Do get well soon Paul. I'm not your biggest fan, but I've been through the surgery/pain-killer thing myself and wish it on no-one.
  2. I *suspect* the copper plates & caps will do the job. wrt copper. If you went to stainless you could electro-plate a copper layer in the interior - not hard to do. [for those who might care to pick fights, the rectification fluids & vapor are not electrolytic, and the joint is not exposed], but frankly the glass column is likely to be educational. I recently heard the Beam uses a stainless column but adds copper pipe stacked within the column at some unspecified plate. I can't attest to the accuracy. Odd but plausible.
  3. I hate to tweak Silk's excellent contribution, but there are a couple advantages to "dual flow"/sieve (perf) plates over bubble caps, in some applications. Perf plates don't easily foul (given adequate hole size for the media) , so they can (must) be used in a stripping column for grist-in. Perf plates have lower pressure drop, making the product separation a bit more efficient. Somewhat higher efficiency (closer to a theoretical plate) - *IF* operated in a tight range of vapor flow - which is practically impossible for a non-continuous still. OTOH sources claim a 1.5:1 type turn-down ratio for a perf plate, vs a ~2.5:1 turndown for a bubble plate. Floating valve plates have a huge turn-down, up to ~8:1!!!, but more pressure drop, cost & fouling are worse. I've never seen small scale valve plates. == Yes, given your application bubble-plates are the obvious choice - for any small scale non-continuous rectification.
  4. Nice work. That *looks* like a lot of heads per the amount whitedog based on flow rate. Stumpy's had problems w/ his hardware supplier previously https://www.idahostatesman.com/news/business/article187541748.html
  5. Yeah - mibad - 95.63% by mass, the ABV azeotrope is close to 97% ABV
  6. Hi Silk, thanks. I always find you comments intelligent and on point. On 2) I assume most know, but pH drops with increasing temps, and it's not a trivial amount. An ATC meter reads pH at the sample temp, which is usually unlikely to be the mash tun temp unless you have a high temp process meter, so you have to apply a correction. So pH 5.7 for the HTAA at 85C, will read about 6.2-6.3 if the sample is cooled to 25C, and the meter can't account for it. pH 5.8 @ 50C = pH 6.17 @ 25C pH 5.7 @ 85C = pH 6.45 @ 25C pH 5.3 @ 63C = pH 5.83 @ 25C The delta-pH values for the three rests would be -0.28, -0.62 if measuring at 25C. >>only adjust down for GA, ... Right! My view is that you can likely the 'split the difference' in pH for the gum-rest & liquification rest (BG & HTAA). The HTAA rest does not need to be as complete as the GA rest. The main purpose of he HTAA rest is to prevent the branched amylopectins from trapping all the water, thus stalling the the hydrolytic enzymes (and of course viscosity). Acidifying accurately for GA is critical for good attenuation. https://www.westlab.com/blog/2017/11/15/how-does-temperature-affect-ph >> There is a really popular gelatinization temp chart that's made it's way around the internet. Ignore it, it's garbage. ++. This (below) is the inaccurate chart. It dates to a 2009 aussiehomebrewer forum, and the guy says he pulled it together from another amateur HB forum. The PDF page attached is from "Food Chemistry" 4th Edition by Belitz, W. Grosch, P. Schieberle. Note that Rye is way off in the chart. >> 4) Add your HTAA right after your glucanase rest is complete, it helps keep mash thin. Depending on the specific enzymes used, you may be able to add the HTAA with the GA. In any case I think the arabinoxylanases + BG may improve the rest time and the SG readings late. gelatinization.pdf
  7. FWIW Vendome makes a still a little larger than yours (12" diam) for 3.1gpm (700lph). I don't think you'll get 1000lpm or normal wash feed through an 8" (200mm) rectifier at any reasonable vapor velocity. Reboiler design is a complex issue, particularly if you are processing wash grist-in. Many stills this size and smaller use direct steam injection to avoid fouling. Condensers are just heat exchangers, and they have to be sized to the load. To get 100% reflux from a top plate you need to match the heat of vaporization of the two components (ethanol&water) according to there molar flow rates. 95.63%ABV is the azeotropic limit to water:etoh separation near atmospheric pressure - you can't get to literal 96%ABV that way.
  8. 100% rye is a sort of torture-test. You might try a <70% and see how it goes. There are Dupont viscosity reducing enzymes from Gusmer's available aimed at rye & wheat. I don't have experience but Headstill wrote about them a while back. These reduce the arabinoxylose & hemicellulose 'gums'. The prices aren't bad at all, but the minimum qty is like 25kg. IoR is an indirect measure of sugars (and anything else that differs in rotation from water) , OTOH hydrometry is also indirect and just measures the density. If you want to get hard-core there is a Fehling's test (strips are available as Clinitest) for reducing sugars. You can even measure glucose (not maltose etc) using a diabetic test meter & strips - very easy & cheap. In the US these measure in milligram/deciliter with an accurate range ~50-200 mg/dl - so you'll need to understand dilution. A 100 reading on a diabetic meter is 100mg/dl or almost exactly 0.1 Plato (of glucose only). I'm not suggesting these as a regular procedure, but it's nice to have a couple tools in the drawer when things are unclear.
  9. The smallest one I've ever seen close-up was about 8ft diameter. That was used in a chemical plant. I've been told they are sometimes used in petroleum cracking. A Japanese company makes some tiny ones with a 1 to 3 m^2 transfer surface, but I'll wager the price is terrific.
  10. Roger - your 2.5% grade in a 2" tube would dictate a minimum ~33gpm @ ~1meter/sec to keep it filled.. Yes that is adequate for both turbulent flow but only marginaly improves the turndown ratio. Of course you need to be able to fill and empty the shell unlike ...
  11. Mostly agree. At gelatinization the amylopectics go into solution (assuming you have enough water or some alpha-amylase) reducing the amount of solids by 60-70%. (oddly amylose is insoluble). Also the viscosity increase makes the sedimentation velocity drop, but also reduces the Reynolds number (turbulence). Of course the viscosity drops a lot more at sanctification and fermentation. >>If you are recirculating back to the tun, there is no reason to run a slow flow rate. Faster the flow the better the efficiency, don’t get fooled thinking the smaller delta t is a problem. That's not my only use-case. I need to flow milled wheat&rye from a 'gum' tank (~50C, arabinoxylan & hemicellulose degradation) to a gelatinization temp tank near 90C and I have waste-heat I could use to pre-heat it. So not gelatinized, low flow rate, one-pass. >>And those idiot dairy farmers didn’t bother to consider smaller inner tubes Maybe not such idiots, https://www.dairyfoods.com/articles/92787-selecting-the-best-heat-exchanger-for-dairy-pasteurization I see "dual tube", tubes-in-shell and lpates from dairy HX vendors. >If you are recirculating, optimizing HX efficiency is a whole lot less important, since you can just trade time or adjust flow rate. Unless you are paying for water or to run a chiller. You need velocity in the counterflow HX to improve heat exchange in a turbulent regime, and this additionally keeps the solids moreso in suspension. Some have dimpled or corrugated tubes to improve turbulence. I wish that spiral plate HX were available in a size I need - they have no issues w/ slurries.
  12. This is NOT a recommendation - I have no experience with this company, but ... http://sellerscleansteam.com/
  13. It's possible to clog any slurry pipe. You'll find entire texts devoted to 'slurry flow', as the concept is used in mining & mass-transfer. I never suggested it was a bad design, but it's always important to understand the design limitations. At sufficiently low flow rates you will get sedimentation 'sanding' of the solids.
  14. Hey Paul, that's a fantastically priced tube-in-tube, HX. So how exactly is it operated? The 2" inner tube seems to drop ~3+ft over ~40ft length, so that would cause a 50-60 gpm water flow due to gravity. Because of that I assume you pump mash in at the bottom (to avoid airgaps), and water in at the top (for a counterflow). But aren't there airgaps in the water jacket???
  15. Then I've done the impossible ... again (never in a good way). Tubes will clog/wad-up/plug given a sufficient incline and a low enough flow-rate or else on/off pumping. I expect that Paul (and Richard1's) system has a shallow enough incline and high enough flow rate to avoid that. Back when I was fussing with this problem we were using a peristaltic pump, and tho' they can handle some solids in a slurry, they don't like that big wads of particles on the inlet side. Tube-in-tube, like Paul's, has an advantage in that the pump will apply a lot of pressure to any clog/wad. In Richard1's heat-exchanger with the multiple tubes-in-shell, if one tube clogs, the others limit the pressure available to break-up/move the clog.
×
×
  • Create New...