Just about all brewery wastewater systems will need a lift station, aka pump station. The sewer in the street is usually a few feet below grade. The wastewater pipe leaving your brewery will also usually be a few feet below grade. You might be able to gravity flow all the way to the sewer. But if you need to do pretreatment you will likely need to add a tank somewhere. You’ll wind up either lifting (pumping) water up into the tank- or lifting water out of the tank if it’s underground.
For a lot of reasons, I prefer precast concrete for underground tanks. See this page. A concrete tank should be coated on all sides, especially the interior ceiling and upper walls. The area above water line is actually more corrosive than the parts under water- due to hydrogen sulfide gas and water vapor creating sulfuric acid (see here). I’d love to say underground plastic tanks work, but the water will be too hot leaving your brewery, averaging about 110F or so. There will also be spills and other events leading to water that can be close to 200F in that tank. Most underground plastic tanks are rated for no higher than 120F. A collapsed wastewater tank because of an overflowing hot liquor tank would be a major bummer.
My personal preference is for one large-ish underground tank. Outdoors, underground, out of sight, out of the way, can be traffic rated, freeze resistant, and versatile. Keep the tank mostly empty, if there is a problem out there you have headspace in the tank to absorb water before things get ugly. Rough in some extra piping and conduit during initial construction, if you need to modify the tank later you shouldn’t need to excavate.
Please contact me for more details about brewery lift station design. Remember, don’t reinvent the wheel. Go with what works so you don’t have headaches due to improper design.
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