Silk City Distillers

We're doing the same thing.

However - Direct steam injection is our approach, but we've got filtered steam so it makes that easy. Can't comment on the elements, only be sure you do the math on heating before you invest the money. You don't want to be in a position where it takes you 8 hours to get to boiling. 200 gallons, from 75F to 212F, in one hour will take 80kw. That's 300 amps on a 240v service - probably beyond your service capacity. Moving down to 30kw (125 amps) - now you are going to need about 3 hours to heat. One good alternative is to use an on-demand hot water heater like a Rinnai or Noritz. They have a high btu gas-fired commercial model that will get near 170-180F output. It will probably save you hours of time every mash.

On the motor - don't look for a milk tank replacement motor, they are too small, too slow, and too expensive. Instead retrofit a washdown motor and gear reduction for the agitator, use the existing paddle. It's going to take some fabrication and welding. If you can't fab, there is a good chance you can find a nice Lightnin' mixer on the surplus market. Look for something 1/2-3/4 hp.

Another thing to keep in mind is the insulation on these milk tanks is very good, with the tops on, don't for one second think you are cooling from cook temperatures to malt temps, to pitch temps, in any reasonable amount of time - you will need some sort of active cooling. Our Mueller holds temps very well, something like 1-2F drop per hour.

Steam trumps water - on a straight btu to btu comparison, water is going to be substantially slower, or if your still jacket is not appropriate, water may not even work at all. If water was easier than steam, we'd not have had 300 years of industrial steam use.

There are commercially available ASME rated solid fuel (aka wood) steam boilers. I would wager a bet that they would be significantly more expensive than oil or gas counterparts. Really though, don't waste your money on a hydronic boiler.

Is it that you don't have natural gas at your location?

I'm trying to find out how to show an inspector that the pot still is an open system and has minimal pressure.

The compressor idea is an interesting one from a practical perspective. However, most inspectors understand pressure relief valves, especially when bearing the certification marks required in specific jurisdictions. Those are devices they see every single day.

You can find PRVs bearing the approval marks as low as, or in some cases lower than, 5psi. I'm talking about for the still boiler proper, not the jacket, which will likely be 15psi.

You can make the case that the system can't hold pressure, and it could be a logical argument, but realize that inspectors aren't engineers, and it isn't up to them to determine the merits of your argument. But a low pressure relief valve bearing a mark (ASME, etc) - That is a language that these guys speak. If you want to look like you have your stuff together, plumb the relief line to a safe outdoor location (so you aren't trading a dangerous pressure situation for a dangerous vapor situation).

These guys are busy, it's not their job to know how distillation equipment works, or to spend the time to figure it out.

By the way, the fact that a system is "open" by our definition, doesn't mean it can't build pressure if the equipment fails. Imagine a condenser bracket weld breaks, the weight of the condenser pulls the vapor piping and kinks it shut. Now you don't have an open system. Recent events should be clear in all our minds.

Our still (and surrounding area) is Class I Division 1 Group D by our own decision. Agitator motor is explosion proof, rigid conduit, sealing glands, etc etc. We removed all other extraneous electrical from the area. However, with regards to NEMA 7 enclosures, we found it more cost effective and realistic to move controls and other electrics outside of the classified area (rigid conduit is cheaper than enclosures). For example, the VFD for the still agitator is outside of the classified area in a standard metal enclosure. Key thing to realize is that removing non-essential wiring, fixtures, plugs, etc is going to be significantly more cost effective than trying to replace them with their classified counterparts. Things like RTD temperature sensors and pressures sensors are also classified or in classified enclosures, along with intrinsic barriers at the controllers. We've got combustible gas monitors with interlocks to shut down everything but the condenser water flow.

Try adding some silicone antifoam on your next strip, or potentially dial back the power. Are you running a visually-closed system?

Puking?

Dave,

I've got 2" TC to 2" Male NPT and 1.5" TC to 1.5" Male NPT. I could have sworn I had a couple pieces of the mismatch combo, but I can't seem to find them. If you can make either of these work let me know and I'll send you out one. I can measure up the 1.5" TC and see if you can cut it and weld on a 2" ferrule (I have a bunch of those too).

Have a few hours free tomorrow afternoon/evening in Denver - anyone around? Was hoping to pop into a distillery or two but nobody seems to have any open hours posted on their websites.

Yeah I believe I have a few, how many do you need?

Assuming there are no obvious design flaws (highly unlikely on a Vendome), it's one of two things:

Steam pressure too high on the kettle, too much power input causing vapor speeds in excess of design. This causes entrainment flooding which is commonly associated with top plate flooding (tiny droplets of distillate get carried upwards with the vapor).

Dephlegmator/Reflux condenser temperature too low - this would increase the volume of reflux being generated and can overwhelm the ability for plates to drain (mentioned above).

There is a kind of balancing act that you need to get a feel for. If your dephlegmator temperature is too low, you might find yourself needing to increase the kettle pressure to compensate for the higher reflux ratio. But, if you don't need the higher reflux ratios, it would be much easier to adjust by running a higher dephlegmator temperature.

Do you have any kind of dephlegmator temperature monitoring or control (thermostatic valves)? If you did not, your system might be impacted by changes in your cooling water or flow rates.

Check out "Study of Rum Distillery Waste Treatment and By-product Recovery Technologies" on the EPA website. By far I think the most common large scale commercial approach is anaerobic digestion.

There are a ton of journal articles discussing this from across the Caribbean.

Some details from another article on the EPA site, "Rum Distillery Slops Treatment by Anaerobic Contact Process":

70-100gm/l COD

75-85gm/l TDS

3-10gm/l TSS

From "Investigation of Rum Distillery Slops Treatment by Anaerobic Contact Process"

70-100gm/l COD

20-60gm/l BOD

25-75gm/l TDS

7-10gm/l TSS

1.8-2.5gm/l Nitrogen

80-100gm/l Phosphorus

2-10gm/l Sulfate

pH 4.0-4.7

What's your yeast nutrient protocol look like?

1. A stripping run is distillation, plain and simple.

2. There is no standard use of the terminology. Some manufacturers use the number of plates, plates plus pot, theoretical states, or number of times it goes through the process. Arguable that tray count is somewhat irrelevant on it's own, since it's the interplay of stages plus the reflux ratio that governs the output purity (a 3 tray column can output the same abv as a 5 tray column with the only difference being reflux ratio). IMHO, this has transcended into marketing, as evidenced by $300.00 vodkas claiming hundreds of distillations makes a better product.

3. Either.

Not doubting that it can be done very cost effectively, I know many have done it, but there is a difference between going into a venture like this with a realistic budget, and being frugal about how you spend it, versus going in extremely uncapitalized, with no room for buffer. There are plenty of assumptions that are easily blown out of the water after you've started buildout. You may also find your local jurisdiction is not as lax as another. You may find that the neighbor that loved your idea yesterday is now battling for all-out war. You could get stuck behind totally unexpected government delays (remember the shutdown?). For those reading who are thinking about starting, do yourself a favor and take a pessimistic stance on budget, not an optimistic one. I'm sure there are startups blowing up left and right at this point, before ever opening their doors, that we never hear about here.

Both Appleton and Killark publish guides to NEC Articles 500. It's a good guide to understanding the kinds of equipment you would see within classified areas, as well as what the commonly understood boundaries based on typical situations. Sometimes your local electrical contractor supply house will have the printed versions of these books on hand for free. Generally these will give you some good insight into the kinds of things your AHJ are insisting. The intent isn't to make you an expert, but to understand their position.

http://www.killark.com/literature/2011NEC.pdf

http://www.emersonindustrial.com/en-US/documentcenter/EGSElectricalGroup/brochures_flyers_pdf/nec-code-review-2014-appleton.pdf

Also critical is the NFPA 497, you can get free access here. If you haven't yet, take a look at the last 20-30 pages or so, you'll find them very helpful.

http://www.nfpa.org/codes-and-standards/document-information-pages?mode=code&code=497

Typically, the crux of the argument is what is considered a classified area, and for what reason, everything else is secondary.

Thanks Mike - I hadn't considered one of those dry cooler units, not sure what the cost differential is compared to a standard cooling tower. Small cooling towers (10-20 ton) look to be pretty darn cheap.

Agree it couldn't be the only option, but there has got to be a better way then running the chiller all year round. Not to mention the fact that we've got limited chiller capacity. If investing in a tower vs a larger chiller is more cost effective, reduces operating costs, and improves sustainability, I'm all for it. Just don't know if it's going to live up to that.

Really just wish someone would bring the free lunch back.

My initial thought was to run the condenser/heat exchanger recirculating loop back through the tower before returning to the reservoir. Heck if I could take down the coolant return temperature down to 84f, I could significantly extend the capacity of the reservoir and the ability for the chiller to keep up. The other angle where I thought this could really shine is initial cooling of cereal mashes from 212-150. We're talking about coolant return temps way above wet bulb + offset.

Anyone running a cooling tower and care to share details? Sizing, flow rate, input/output temps, region? Effectiveness?

Suspect that it would be considerably more cost effective from an initial investment and an ongoing operational perspective than a larger portable chiller unit running indoors. Out in hot and sticky NJ, suspect it will be largely worthless in July and August, but that still gives us a very wide operating window (7 months) from March to November.

Went through a similar process with our local sewerage authorities. We gave them a number of papers from academic journals that provided estimates of the BOD/COD/TSS, and then made our case based on those numbers. The wildcard is the stillage to overall wastewater ratio, and not the BOD/COD from the individual processes. Problem is, you end up with a BOD range so incredibly wide that your engineer will probably need to design for worst case. If you are holding all wastewater and stillage in holding tanks, the combined BOD would probably be in the ballpark of 500 - 5,000ppm.

To give you an idea of how much the BOD will differ by type of waste, and how much of an impact that process will make. I've seen estimates of the BOD of yeast slurry off the bottom of a fermenter at 135,000ppm. If you are using conicals and settling/pulling off yeast prior to distillation, and you can dispose of it elsewhere, you'll make a material impact on overall BOD.

Here is a good resource I found that covers the BOD by process and type, check tables 11.4 and 11.5.

http://www.biologydiscussion.com/biotechnology/waste-and-waste-water-treatment-with-diagram/8201

You'll quickly see that anything you can dispose of as solids, or even just as slop, will significantly drop your overall BOD. You'll also find that once you start to try to reduce overall water consumption, your BOD will go up.

Our sewerage wanted us to hold all wastewater, CIP, rinse water, and stillage in a holding tank, adjust for temp and pH, allow for settling, and then discharge. Which makes sense, since if we are using 10 gallons of wash/rinse water for every gallon of stillage, we drop the BOD to 1/10th of the point reading.

Check the brewery literature as well, I recall seeing some journal papers specifically on brewery septic design.

Wow, glad I'm not the only one who was impressed by the Stranahan's knee wall setup. It's so brilliant because of how downright simple and inexpensive (except for maybe the Class I Division 1 exhaust fan). You get spill control as a bonus too.

The local fire marshall is going to have more to say about an assembly occupancy being located on a second floor above a potentially hazardous occupancy.

Loading with 45% ABV and running through 3 or 4 plates, you may have an issue keeping it under 80%.

You need to check the input water TDS versus the output against the rejection rate of the RO membrane to get a good idea of whether your output water is in-spec. If source water is very high in TDS, an output of 7PPM might be realistic (excellent even).

Some of the low-pressure/high-flow rate (or lower cost) membranes have rejection rates as low as 90%, new, right out of the box. With 70ppm input water, you'd realistically get 7ppm output water.

Running a higher-end membrane with a 98% reject rate, you'd probably have an output TDS of 1, but if your source water is very high TDS, say 300 or so, then your output would move to 7. No free lunch.

True zero (or very low) TDS water is tough to achieve, you might need to add deionization stages to the mix to get there. If you are a water geek, you'll probably be doing this anyway.

You talking with the guys in Saddle Brook?

Great story, and amazing photographs...

From the FAQ on that notice:

Will FDA take action against other products containing added caffeine?

At this time, the FDA is sending Warning Letters to four manufacturers of alcoholic malt beverages to which caffeine has been directly added as an ingredient. Other alcoholic beverages containing added caffeine may be subject to agency action in the future if the available scientific data and information indicate that the use of caffeine in those products is not GRAS. A manufacturer is responsible for ensuring that its products, including the ingredients of its products, are safe for their intended use and are otherwise in compliance with the law.

Does this action apply to coffee-based liqueurs?

No. These Warning Letters are not directed at alcoholic beverages that only contain caffeine as a natural constituent of one or more of their ingredients, such as a coffee flavoring. The alcoholic beverages that are the subject of FDA's Warning Letters are malt beverages to which the manufacturer has directly added caffeine as a separate ingredient.

Sorry, boiler horsepower, BHP, not mechanical. 1bhp = ~9.8kw