I have helped many distilleries with their wastewater challenges over the years. One common feature they all have is they’re all different! The wastewater coming out of a distillery will also differ a lot of one place to another.
Most distilleries start out as a brewery, making ‘beer’ which they then distill into alcohol. Other distilleries buy alcohol and distill, age, and flavor it. Some sell bottles of whiskey or vodka, others sell packaged ready to drink cocktails. And then there is the product, bourbon, gin, vodka, tequila, whiskey, and what have you. They all require different raw ingredients (such as corn, barley, rye, syrups, etc) and different equipment!
The still itself could be a pot still or a continuous still- or both! Cooling could be glycol or cold water, stillage could go to drain or to a farm, CIP water could be reused or single use, etc.
Fermentation is very different for a distillery. It’s often on the grain, then the entire contents of the fermenter are transferred to the still for distillation. This kills the yeast. The solids leftover at the bottom of the still are called stillage, similar to spent grain for a brewery but with the yeast. It’s well cooked, soft, and soggy. This is quite a bit different from brewers spent grain which has only been steeped in hot water and is mostly intact- though crushed. Of course, being a wastewater guy, stillage should go to a farmer and not to sewer.
Most distilleries have a hot water problem. They use cold city water in the condenser (condensing alcohol vapors, making hot water). This hot water often goes to drain, and it can be a lot of water! I’ve seen anything from 1-50 gals/min of clean hot water going to drain for 12 hours a day. Of course a simple question is why don’t they reuse that water? They can and do, but there are only so many needs for hot water. Stay tuned on that subject.
CIP water at a distillery may be reused many times, for more than at a brewery. When it is dumped it can be pretty dirty. All of that being said the wastewater going to drain can be cleaner than that of a brewery.
However as you can see above, it is very case specific. Feel free to reach out if you have questions or need more information- or heck, if you want to provide more detailed information.