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Distillery effluent processing for spent wash/pot ale/spent lees

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vsaks    0

Do you process your spent wash/pot ale/spent lees before discharging it down the sewer ?

I am looking at the sewer rates here in California, and the COD load surcharge (based upon the expected COD load of 46,000 mg/liter) will add 10x to the cost of just discharging water.

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COD or BOD, or both - and what about TSS?

Couple options...

Low cost/easy options:

Recycle 20% as backset in new wash - you take 20% right off the top, free money, you save on both sides.

Dilute spent wash with cleaning water - use alkali cleaners - not only will you reduce overall COD, but you'll help shift pH balance.

Dilute spent wash with cleaning water and cooling water - depending on your sewerage costs, you might find it to actually be cheaper to waste water for cooling, dilute your wastewater to the point at which you pay no additional surcharges. If there is a chiller in the mix, you might find co-mingling of all wastewater to actually be cheaper than running a chiller and disposing of stillage directly.

Make sure you are side-streaming your high-test waste - no yeast down the drain, ever.

Medium cost options:

Dilute spent wash with cleaning and cooling water - inject ozone to drop COD - if you use an oxidizing cleaner this will help, but you'll then need to manage pH separately. This may not impact BOD.

High cost options:

On-site sewerage treatment facilities - pond or tanks - microbial digesters.

Or ... Just pay ...

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OldSpye    8

COD or BOD, or both - and what about TSS?

Couple options...

Low cost/easy options:

Recycle 20% as backset in new wash - you take 20% right off the top, free money, you save on both sides.

Dilute spent wash with cleaning water - use alkali cleaners - not only will you reduce overall COD, but you'll help shift pH balance.

Dilute spent wash with cleaning water and cooling water - depending on your sewerage costs, you might find it to actually be cheaper to waste water for cooling, dilute your wastewater to the point at which you pay no additional surcharges. If there is a chiller in the mix, you might find co-mingling of all wastewater to actually be cheaper than running a chiller and disposing of stillage directly.

Make sure you are side-streaming your high-test waste - no yeast down the drain, ever.

Medium cost options:

Dilute spent wash with cleaning and cooling water - inject ozone to drop COD - if you use an oxidizing cleaner this will help, but you'll then need to manage pH separately. This may not impact BOD.

High cost options:

On-site sewerage treatment facilities - pond or tanks - microbial digesters.

Or ... Just pay ...

Ponds are cheap. Legal fees are expensive.

I'd love to do a pond since we actually have the room to do it. I just can't get my head around the hoops we'd have to jump through to get it approved.

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vsaks    0

Thanks for the feedback. The surcharges are for lbs of COD and TSS.

But I suspect TSS is easier to manage with filtration.

Since the COD/TSS costs are per pound, spreading it out over larger volumes by diluting doesn't help.

Our pH is just about right, so adding backset will drop it too low.

Ozone looks like an interesting option, is anyone using it, or have recommendations for a solution.

We are planning to distill with the yeast for a fuller flavor, so what we'll get in the end is a brown bread/yeast smelling pot ale. Wondering if the boiled yeast will actually settle, or if there are some options to do encourage it to flocculate.

There seem to be aerobic treatment units for $5-6K, which'll process a daily volume of 500 gals each. They don't smell like anaerobic digesters. Has anyone tried them for pot ale ?

COD or BOD, or both - and what about TSS?

Couple options...

Low cost/easy options:

Recycle 20% as backset in new wash - you take 20% right off the top, free money, you save on both sides.

Dilute spent wash with cleaning water - use alkali cleaners - not only will you reduce overall COD, but you'll help shift pH balance.

Dilute spent wash with cleaning water and cooling water - depending on your sewerage costs, you might find it to actually be cheaper to waste water for cooling, dilute your wastewater to the point at which you pay no additional surcharges. If there is a chiller in the mix, you might find co-mingling of all wastewater to actually be cheaper than running a chiller and disposing of stillage directly.

Make sure you are side-streaming your high-test waste - no yeast down the drain, ever.

Medium cost options:

Dilute spent wash with cleaning and cooling water - inject ozone to drop COD - if you use an oxidizing cleaner this will help, but you'll then need to manage pH separately. This may not impact BOD.

High cost options:

On-site sewerage treatment facilities - pond or tanks - microbial digesters.

Or ... Just pay ...

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Simon13    0

Interesting topic.

Do you process your spent wash/pot ale/spent lees before discharging it down the sewer ?

I am looking at the sewer rates here in California, and the COD load surcharge (based upon the expected COD load of 46,000 mg/liter) will add 10x to the cost of just discharging water.

Traditionally, in Scotland, draff would be mixed with pot ale and used as animal feed. Old books say that pot ale was used as a high quality fertilizer.

Given that we are going to be used Organic certified cereals, we hope to team up with organic farmers (the feed for the cows has to be organic certified). Other options are to have a bio gas ingester and you can harvest some gas for burning and have a high quality fertilizer as a by product or to dry out the draff and burn it in a biomass burner.

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vsaks    0

That works if you have farmers close by. In suburbia here we are out of luck :(

We'll have to pay to have the spent grain taken to a compost pile too, but that's not that much.

Interesting topic.

Traditionally, in Scotland, draff would be mixed with pot ale and used as animal feed. Old books say that pot ale was used as a high quality fertilizer.

Given that we are going to be used Organic certified cereals, we hope to team up with organic farmers (the feed for the cows has to be organic certified). Other options are to have a bio gas ingester and you can harvest some gas for burning and have a high quality fertilizer as a by product or to dry out the draff and burn it in a biomass burner.

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vsaks    0
3 hours ago, Afilters said:

I can help you with dewatering if need be.

 

 

Thanks. We'll be lautering so our main concern is liquid COD/BOD

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