Water usage and conservation

[pogriallais]

Hi Guys,

I searched the forum for this information but didn't come accross anything relevent.

I'm currently trying to secure a building permit on an agricultural building and permission to abstract water from a stream that runs through the property. I'm in a rural location and the local authority is favourable but quite conservative about a distillery in the area- they're not used to this kind of thing.

Regarding process water I anticipate I'm going to be using 1250 gallons per week by the end of year 2.

One manufacturer of equipment stated that I can expect to use 14529 gallons per week for cooling water producing at the level quoted above. What can I do to minimise cooling water abstraction and discharge from the stream. One method I have come accross is to re-use cooling water for mashing. Any other ideas would be much appreciated.

Thanks in advance.

[Natrat]

pogriallais,

The distillery I am currently running is in a desert area where water is scarce and conservation is required. The best way to conserve water is to use a reservoir for your cooling water. With no chilling, two 600 gallon reservoirs get me through cooling a 100 gallon still operating 4 days a week, and only once have I had to cut in the supply water for cooling. It gets far more efficient if you can use a chiller to cool your water...cooling it while you run is often a very large load for a small glycol chiller, but if you let it run all night, your supply water can be very cool and will support your distilling. If you have cold nights or a body of water nearby, a pumped loop can help cool water down without actually letting it go down the drain.

Your water for proofing is not a lot...it's cleaning your equipment that uses the bulk of your water. Typically, for every time you clean your still, you'll need 2.5 x the capacity of your still. But that can be reduced by judicious cleaning practices. Currently, I use about 20% of my still capacity per cycle plus rinse water, which for me comes to about 50 US gallons a day (about 190 L)

Because of water restrictions, I often use my leftover chem to wash the floor, etc.

As you mentioned, another strategy is capturing your cooling water in an insulated tank to use for mashing...I don't do that because my reservoirs are indoors and open top, so I add some disinfectant (quaternary ammonium) to discourage any growth in the cooling water. My cooling water is for cooling only!

If you have lots of time and/or lots of money, you could conceivably catch all your drain water into a weir, and after pH adjustment, run it into a small artificial swamp or engineered wetland...and then release the water OR re-use it after filtration. I know a brewery that re-uses almost 40% of the water that goes into the drains.

Of course, if discharging hot, clean water is no issue, then you can simply cool with stream water, and discharge the heated water back into the stream. If your loop pumps slowly, then your discharge will be quite warm (>70 C) but if you pump at a rapid rate, then your pump discharge can be much lower (around 20-30C) which would be less likely to disrupt the stream ecosystem. In fact, you could use stream water to cool, capture the hot in a reservoir, use what you want for mashing, and release the rest back to the stream when it has cooled sufficiently.

It all depends on exactly what the concern with the stream is, but I suspect you could engineer your system to have minimal impact using a combination of the strategies above. A small engineered wetland using your suspended solids could (in many cases) benefit the ecosystem as a whole.

Good luck!

[MG Thermal Consulting]

As you grow, it is proven the most effective way to run a cooling system from a constant control point of view is from a refrigerated chiller and a reservoir tank.

If you are crash cooling mash, it pretty much is a must unless you have a huge reservoir.

As you cooling water from outdoors goes anywhere above 60F, then the effectiveness in running your still is problematic an near impossible if you need to crash cool mash to near 70F.

Lately, some of the distilleries have turned to underground cisterns using treated water and add the chiller unit to supplement.

Basically they are trying to get a little buffer using the 55 degree ground. Care must be taken with insulating lines and heat tracing for outdoor piping as well.

Mike

[Silk City Distillers]

Suspect it might be easier and less costly to go with reservoirs and a chiller as opposed to even initiating a discussion about discharging non-contact cooling water or other process water back into the local ecosystem. Regulations and requirements are going to differ everywhere, but in many places the discharge of hot water would be considered pollution. A few used IBC totes and a chiller will probably cost less than the environmental impact study you'll need to submit with your permit app...

[pogriallais]

Thank you for all the feedback and ideas- I really appreciate it. It seems like the best option at the moment is the resevoir(s) and chilling if necessary.

Pádraic

[pogriallais]

Just on the same question of cooling water. Can it be used indefinitely without any replenishement? Or should it be replenished with 'fresh' water at any particular rate?

[Bier Distillery]

It gets far more efficient if you can use a chiller to cool your water...cooling it while you run is often a very large load for a small glycol chiller, but if you let it run all night, your supply water can be very cool and will support your distilling.

Any recommendations for a small glycol chiller?

[MG Thermal Consulting]

You can see samples on my website, from the standard packaged unit to large scale central chiller plants.

Regards,

Mike Gronski

www.mgthermalconsulting.com

[MG Thermal Consulting]

Pog,

When you put together a closed loop chilled water system, it normally either also includes glycol (acts like an antifreeze if the chiller is located outdoors) or is treated with inhibitors (anti-biologicals) which makes it "process water" and not suitable for mixing with your sanitary water.

Mike

[Natrat]

Bierling,

all respect to Mike, but I've not used his equipment and can't comment. A good option I have found for a small operation is the ChillStar series from ProRefrigeration. Comes in 2 HP to 5 HP, with the 5 coming in somewhere around $11k new. They have one that's even smaller than 2 HP, but I don't think smaller is really feasible unless you're running a 25 gallon still.

[MG Thermal Consulting]

It might be a stretch (shipping to Ireland) but I'm sure there are equivalent manufacturers there.

Some here in the US are placing underground cisterns (poly, fiberglass or I know one is rebuilding a city water station with cement tank) utilizing ground temp of 55F to help out. This doesn't work for Southern US but in the Northern States, underground storage is used and well as dry coolers in the winter acting like a radiator to provide cooling for under 30F outdoor temperatures.

So many here rely on revitalizing old dairy and pharmaceutical tanks as well.

Mike