BREWERY WASTEWATER 101

DRAINS AND PIPING

We all know water flows downhill, so let’s start with drains and piping. For starters your brewery wastewater system should be separate from your domestic wastewater (toilets, sinks, kitchen).

Very important: Domestic wastewater (toilets, sinks) should flow directly to the sewer, your kitchen (if applicable) will probably need a grease trap and then straight to sewer. The brewery system might also flow directly to the sewer, but make sure it’s in a separate pipe as it leaves your brewery.

Once outside the building the domestic and process pipes can combine before they reach the sewer. One reason for this is if you wind up having to do some sort of pretreatment before sending the brewery wastewater to the sewer, even years down the road, you will be very happy to have separate pipes so you don’t have to pretreat turd water; or dig up your slab to separate the pipes. Another reason is you may be required to install an inspection port or manhole, the location for this varies town to town. Some places would want an inspection port on just the process wastewater, other places want it downstream of the tie in with the domestic wastewater pipe. It is possible to locate one manhole at the tie in location, so city workers can sample just process wastewater, just domestic wastewater, or combined wastewater.

This is an example of an inspection manhole.  Flow would be from 7 o’clock to 2 o’clock.  With something like this the city can get a sample from the individual pipes coming in to the sewer, as well as the combined sewage.  In a brewery the 3 inlet pipes may be brewery, restrooms, grease trap; all combining in to one pipe and heading to the city sewer.  This is not necessarily required, though in some cases it will be.

OK, enough of that. Process wastewater (from the brewing, fermentation, and packaging process) will flow to the drains. Stainless steel floor drains are the very best. I know you don’t want to hear that, too expensive I know. But floor drains should be considered a permanent part of your infrastructure. Top-of-the-line stainless steel floor drains are available off the shelf from Kagetec, Kusel, and many other sources.

Cast iron drains work, but only for about 10 years; they slowly corrode away in to nothing. Replacing them requires a new drain, concrete work, and a new floor coating. And of course labor to install. Now you can see why $700 on a stainless drain compared to $300 for cast iron is a much better deal.

I am not a huge fan of trench drains, especially those prefab polymer concrete trench drains- and of course these are very common in breweries. They look great when new, however these types of drains have a history of breaking, especially in traffic areas (forklift forks set down hard, keg falls off a pallet, etc.). They’re also susceptible to chemical corrosion. You can read more on drains on this blog post. In 5-10 yrs I predict lots of complaints about these drains.

Since money is always tight, you might consider having stainless drains made by a local welding shop. A great idea mentioned to me is you could have a local sheet metal fabricator make trench drains from stainless sheet on his brake; weld caps on the ends, weld on some concrete anchors, and give it an outlet pipe sized to slip inside your drain pipe. Then drop the whole thing in place in one piece. Trench drain covers are readily available online. One quick detail, cast iron drain covers are acceptable for any drain. They will get ugly, but they’re replaceable. The important part is what is embedded in the concrete or under it.

There are also options to form a drain in the slab itself. There is no actual drain other than the concrete, and the trench gets coated with the floor coating. Just remember, concrete cracks and coatings are rarely permanent.

After the drains, the water heads to pipes under the slab. Again, stainless steel is always best for wastewater piping under your slab, it’ll be there forever. But of course no one wants to pay for stainless in an application they’ll never see. I have had good results with ABS in gravity situations, 4″ minimum diameter. Sometimes you’re lucky and just head straight to sewer from your drains.

If you need to pretreat, now or in the future, you will need a wastewater tank. Since the drains flow by gravity, your first tank will be underground. This underground tank can be a small lift station, or an entire fully automated pH adjustment system. As your brewery grows you can add an above ground tank for more capacity. I have done this many times for many breweries, contact me for more information.