Advice on boiler sizing and still designs

[navenjohnson]

Finally executed a lease and I could use some help finalizing my still designs and power generation choice. I have attached our processing unit schematics. My cousin, a former Seneca master fabricator is completing the work. We are going to purchase a NG boiler and I would like to design a system that utilizes both DSI for the corn mashing and a closed loop for the for the stripping and spirits stills.

My questions are related to size of boiler to purchase and how to best do both the DSI and loop, as well as...

Will my system work?

What advice have you got on the designs?

What size boiler should I buy to operate this equipment?

How do I best size the internal steam coils for optimal results?

Any additional comments are welcome.

The system is laid out as such:

1. 300 gallons of mash is made in a 400 gallon (DSI) mash tun. Raw materials for mashes include corn, oats, rye, winter/ spring wheat, malt, and potatoes for vodka.

2. Ferments are completed in 300 gallon air-locked vats.

3. 150 gallons goes into the stripper ( internal closed loop steam coil)and 150 gallons goes into the preheater/ product condenser.

4. 2 runs completed to make 102 gallons of low wines.

5. 102 gallons of low wines are pumped to the Spirit Still. 28 gallons of water are added to a total volume of 130 gallons (internal closed loop steam coil).

6. The 130 gallons of low wines are distilled resulting in 60 gallons at 70% abv.

[navenjohnson]

I should add that these are existing tanks which we are modifying.

[PeteB]

I am becoming a big fan of pre-heating the next run with the alcohol vapor, but a couple of points for consideration.

Are you going to run 24 hours per day?

If not then you will need some serious insulation on your pre-heater tank to keep the charge from losing much of the heat you captured.

I have built a small continuous stripper that continuously pre-heats the feed and uses it immediately. Heats the feed to near 80 dec C saving about 80% of heating cost, and no cooling water required.

Also, what energy source are you using for your boiler?

Consider a waste oil burner. You can drop your energy cost to almost zero.

( I will probably start a dedicated thread to this subject.)

[navenjohnson]

Thanks PeteB.

Haven't really considered a waste oil burner, but lll look into it. We were planning on a NG boiler around 20hp. Also, would love a continuous stripper from HeadFrame perhaps, but I think that's out of our financial reach right now.

[jeffw]

I would be worried about building up pressure in your preheater. As I see it you are preheating a closed container, as it heats up you will have some issues.

[navenjohnson]

Jeffw, thanks. The preheater has a dephlmator incase the preheat begins to distill as well as a pressure/vacuum valve.

[Jedd Haas]

I am becoming a big fan of pre-heating the next run with the alcohol vapor, but a couple of points for consideration.

I have built a small continuous stripper that continuously pre-heats the feed and uses it immediately. Heats the feed to near 80 dec C saving about 80% of heating cost, and no cooling water required.

( I will probably start a dedicated thread to this subject.)

Pete, I would be very interested in a thread on your continuous stripper.

[PeteB]

I think you might find if you shop around you could buy a continuous stripper (maybe Redboot stills) for quite a bit less than the wash still plus the pre-heater you have designed. Some are very expensive but that is because they are way overdesigned.

I am sure your fabricator cousin could build one. Continuous strippers are very basic. Don't look as impressive as a nice shiny pot but but will impress your bank manager, or maybe not because he won't get as much interest $ out of you

[navenjohnson]

Thanks PeteB.

Anyone here using a continuous from either redboot or head frame? I've definitely thought about that direction.

These stills are being built this way because they are affordable and relatively simple designs and the tanks were the right price.

Does anyone have any thoughts on powering this equipment?

[Silk City Distillers]

I understand the benefit of a pre-heater, but why not just use your existing fermenter coils or jacket and skip the additional tank? Dollar for dollar, and square footage, I'll take another fermenter over a warming tank.

Based on your batch sizes, just make sure you can strip twice in one day - emptying a full fermenter in two batch strips, and pre-heating the next. As long as you can pre-heat and hold the temperature, 20 horsepower should be more than enough power do to both strips in an 8 hour shift.

Very seriously consider the microbiological implications of batch pre-heating your mash. If you can not achieve high enough temperatures to reduce the growth of non-yeast bacteria, you will likely be creating an environment that favors bacteria over yeast. You will likely not be a happy camper if you pre-heat the mash to luke warm, and then wait a few days to strip.

Also, use the heat exchanger output water for pre-heating, don't move the vapor around like that. What happens when you run out of cooling capacity? On second thought, scrap your pre-heat tank design, it probably will not work. Also, why does your preheat tank have a dephlegmator on it?

Also, if that cooling coil in the mash tun is anywhere to scale, your are going to have a really long day, or days, to mash.

[Dehner Distillery]

I love Batch pre-heaters! They are the best, Free energy, Less cooling water used if any, and speed everything up.

Wayward distillery up in Canada has a Smaller continuous still we made.

[navenjohnson]

How much is that Joe?

Also, having done a preheater/condenser set up yourself, any thoughts/advice on the design schmatic above?

[MG Thermal Consulting]

I am becoming a big fan of pre-heating the next run with the alcohol vapor, but a couple of points for consideration.

Are you going to run 24 hours per day?

If not then you will need some serious insulation on your pre-heater tank to keep the charge from losing much of the heat you captured.

I have built a small continuous stripper that continuously pre-heats the feed and uses it immediately. Heats the feed to near 80 dec C saving about 80% of heating cost, and no cooling water required.

Also, what energy source are you using for your boiler?

Consider a waste oil burner. You can drop your energy cost to almost zero.

( I will probably start a dedicated thread to this subject.)

Works for the still but you will need chilled water for the mash cool. One of the manufacturers I get referrals from is setting up his continuous stills that way, uses a shell and tube heat exchanger for the mash which can be used with either city water or a closed loop cooling system.