Maximizing takeoff speed for vodka column

[rtshfd]

I have a 300 G artisan system that has a 16 plate column. I've ran 6 neutral runs so far and find myself pulling my hair out at the take off rate. No matter what I do I cannot achieve a run shorter than 20 or so hours. I'm charging at 40% abv.

I am able to achieve 190 but no matter what I fiddle with (heat or deph) I can't seam to speed things up.

Does anyone have any insight on running a vodka run as fast as possible while maintaining neutral? High heat, high reflux? Low heat with minimal reflux?

[Mash]

Steve should be able to help. If it is an Artisan Still Design product.

[rtshfd]

Steve has been a huge help. However, I'm looking for a general theory on maximizing flow rate. Figured a broad audience would be able to discuss it at length.

[bdkolstad]

How big is your boiler? 20 hours seems like a long time.

[Bluestone]

20 hour runs are not normal for our systems.

Can you give some more detail concerning volume and abv of the charge? And how much heat are you supplying?

[rtshfd]

We are charging with 300 gallons of pot stilled low-wines at 40% abv. We have a 1 million btu boiler and the steam feed valve is just below halfway open at its max during the run so I would guess about 400k btu into the kettle when pushing it hard.

I can stack the plates just fine with vigerous activity. I reflux for 30 mins or so and heads come over compact and cuts are clear and easy. Yet the flow rate is excruciatingly slow. I've tried to input a lot of heat with a tight dephlegmator setting, I've used little heat with a loose dephlegmator setting...I can't seem to get past about 5-6 gallons an hour of 190 without the proof getting wacky.

[ebstauffer]

Do you have the reflux control system or are you controlling flow to the deph manually?

[ebstauffer]

Something is amiss. Once you get heated up your theoretical time to vaporize all of the contents at 400 kBTU/hr is a bit over 6 hours (300×8.34×970÷400000). What temp water are you feeding the deph with? Wondering if your reflux ratio is too high.

[rtshfd]

We have a reflux control system, yes. I set the temperature for which I want the dephlegmator and the system cycles a solenoid in various increments based on the vapor and dephlegmator thermo probes.

Our chilled water system is pumped to the still from a 2100 G buffer tank that's set at 47 deg f and it raises through the run depending on how hard I push the heat.

[ebstauffer]

I'm wondering if the input temp to the deph is too low. That can make things go a bit wonky. I took a look at the gallery pics on your site. Any way to temporarily modify the piping to get ground-water-temp water to the deph? Have you contract the sales rep from whom you purchased the still?

[rtshfd]

I can set my chilling system to 55 or so, but I need the buffer capacity of a lower temp for the time being to get through a hard strip and mash chiller as we are working with only a 5 ton condenser.

I have exhausted the help of the manufacturer without bringing someone on site to help troubleshoot. They have been extremely helpful thus far despite this.

[rtshfd]

To all watching this post, Artisan has ganged up on me trying to figure this out. I want to commend them on their eagerness to help. Initially I was looking for a discussion here on the theory of maximizing takeoff rate of a bubble cap column thinking the problem was how I was running the system. It still may be, but Artisan Still Design is on it. Wonderful company. Thank you.

[Denver Distiller]

I'd have a look at your steam traps, and make sure they're working properly.

[rtshfd]

We are getting plenty of steam. Heatup time is 20 mins or so. This has been an on going problem since the beginning.

[mheisz]

I use the same system for the same purpose with low wines the same way. Here is what I have found to speed things up for what it is worth.

1 I set the dephleg on the first four plate column only after achieving reflux on the 16 plate column and even at that I set it very close to vapour temp.

I heat up the 16 plate column fully without the 4 plate column engaged at high steam input. Once I have reflux and significant reflux I engage the 4 plates and lower the steam input to a minimal amount. This heats the tall column up quickly (getting enough heat through the first dephleg to the top of the second column was very difficult). At that point I carefully control the temp of the second deploy setting to maintain the water temp and slowly increase this to allow through heads. Once I get to hearts I open the second dephleg temperature to allow more through. I try to hold of tails for as long as possible with the second dephleg.

It sounds to me like you are using a lot of calling and negating the heat input in your deplegs or ambient in the tall column.

Only issue I have is flooding in the bottom plate of the tall column which just requires backing of the heat for a bit. I control the temp settings of the dephlegs very closely and monitor them as vapour temp rises to maintain constant water temp.

That is my experience. Not saying it is perfect or even the "correct" way but I really like what I get that way. And I just ran a half charge (slightly diluted with water beyond 40% to have more volume) yesterday off of a 600K BTU boiler in about 6 hours including heat up time.

[mheisz]

I should add that my first runs were 20+ hours trying to figure out how to get to a stable state that worked...that is what I ended up at....

[rtshfd]

Mheisz, how much heat would you say you run with when collecting? Imnonly using the 16 plates as I wasn't successful running both columns at first. But you've given me some ideas to work with. The extra rectification would alone probably let me pull off faster. I do believe I'm running into a plumbing problem where my vodka deph isnt getting enough flow.

[mheisz]

I had a lot of trouble trying to use both. A lot of the time I leave the first dephleg off and let ambient reflux takeover as adding too much causes the plates in the 16 plate column to start flooding (can't drain quickly inning in my setup).

Once I get everything up to temperature I run with my steam valve open about a quarter of an inch or less. i use this to control the flow rate coming out and the second dephleg to control the water temperature in that dephleg to control what comes out. When too much heat gets in (i.e. column starts flooding) I back off the heat until it is back in balance. Controlling those 2 things has worked well for me.

If your dephleg isn't getting enough flow wouldn't it heat up too much too quickly and allow more vapour through and effectively lower your run time but not achieve 95%?

[rtshfd]

That would make sense. I was running through just the vodka column with high heat and high reflux to make a sharper gradient of alcohol. I can take it off faster that way but it puts a lot of heat into my chiller which can't keep up. I had my steam valve about half way open.

I'm running it your way today. I hope I can make it work for me. I'll keep you posted.

BTW, when you say half a charge in 6 hours are you getting to tails? Are you getting the yield you expect? Half a charge of 300G pot would be about 60 gallons of 190, just about

[StonesRyan]

rtshfd, any update on how the latest run went?

[rtshfd]

An update: I was able to troubleshoot my chilling system plumbing with the help of the guys at artisan. My deph wasn't getting as much flow as it needed and was under performing. Now it works great. it's like a new still I have to learn all over again. I've been able to get a steady take off rate much faster than I was able to get previously. That hasn't equated to a 12 hour heart run from a full charge yet but I'm working my way towards that.

[Bluestone]

That's great news.