Thin Stillage, No Solids

[Mountain Brewer]

For those that have a centrifuge or dewatering device, What are you doing with the "Thin Stillage"? The solids will easily be taken by any farmer for feed, but the water or Thin Stillage left over is not beneficial for farmers.  We are not able to discharge to municipal sewer due to high COD and BOD.  Recently came across an article on Makers Mark partnering with Evocation on a stillage solution utilizing biodigestion on the thin stillage to create methane to be used to supplement natural gas.  Are there any other companies or projects of people doing biodigestion.

We are producing approx. 4,500 gals a day of stillage with room for growth from there.  

[SlickFloss]

Your team sucks and your boss is a loser

 

totally kidding I love you 

[Mountain Brewer]

Oh shut up, you beautiful nerd you! Lol I'm over here trying to solve the world's greatest problem and your just over here goofin' hahaha

[38°]

I'd love a good answer too. We're in the same situation. Trying to find a way to filter out yeast before distillation has been a challenge as well.

[Mountain Brewer]

38, 

Out of curiosity, what is your reasoning for wanting to filter out yeast before dististilation? 

We do not filter out yeast in whiskey production, and in fact in rum, it's best to leave yeast in the slurry for when the cell wall breaks it helps with esterfication to produce high Ester rums.. 

If you want a yeast "free" or reduced, my guess would be heavy conical ferms with a racking arm you pull off above the yeast bed. 

 

With Thin Stillage, we continue to seek a more appropriate solution rather than paying to have it hauled..

[38°]

We only want to remove yeast to satisfy our local water district. They don't have science behind it, they just don't want us dumping yeast. Right now we rack and that works ok, just messy, hard to deal with, and the slurry left over still has some liquid which could be distilled. If we can find a better method of removing yeast (before or after distillation) I feel we can get better yields and have an easier byproduct to deal with.

For now this is our only issue, however, with expansion our water co will likely not let us dump anything putting us much closer to your situation. 

 

 

[kkbodine]

7 minutes ago, 38° said:

We only want to remove yeast to satisfy our local water district. They don't have science behind it, they just don't want us dumping yeast. Right now we rack and that works ok, just messy, hard to deal with, and the slurry left over still has some liquid which could be distilled. If we can find a better method of removing yeast (before or after distillation) I feel we can get better yields and have an easier byproduct to deal with.

For now this is our only issue, however, with expansion our water co will likely not let us dump anything putting us much closer to your situation. 

 

 

I'm curious what the water district is thinking. After distillation, the yeast aren't yeast anymore.

[SlickFloss]

On 3/12/2023 at 3:22 PM, 38° said:

We only want to remove yeast to satisfy our local water district. They don't have science behind it, they just don't want us dumping yeast. Right now we rack and that works ok, just messy, hard to deal with, and the slurry left over still has some liquid which could be distilled. If we can find a better method of removing yeast (before or after distillation) I feel we can get better yields and have an easier byproduct to deal with.

For now this is our only issue, however, with expansion our water co will likely not let us dump anything putting us much closer to your situation. 

 

 

You will not have a better yield removing yeasts, you will have less yield you will lose ethanol in that filtration. 

 

 

They're probably thinking yeast yikes activity yikes but they're not keeping into account the yeast are pulverized into oblivion and no longer alive, thus non active. 

 

The large consequences to address for waste water treatment are BOD (biological oxygen demand), TSS (suspended solids), and PH (assuming all your alcohol is out of refuse stream). Biological Oxygen demand can really only be addressed with dissolved oxygen- oxygenated water or ozone. If the other two are handled this one has more leeway. PH can be adjusted, needs to be neutral. PH cannot feasibly be diluted out it must be chemically adjusted, getting close to neutral PH with a large volume has the same impacts on the system as a high PH in a small slug. TSS can be diluted, but it makes your refuse stream larger (which makes neutrality that much more important).