Beer, or some form of it, can be traced back as far back as 5,000 years. From the beer of Medieval Europe during the Middle Ages, to the craft beer we know and love today, that’s a lot of beer consumption. Most people enjoy a good brew—it’s the third most consumed drink in the world—but many don’t realize that there’s a large amount of wastewater and excess yeast that results from the brewing process. Thanks to the Clean Water Act, wastewater isn’t being dumped as freely as it used to be, but it’s still an issue. Unfortunately, finding a way to properly dispose of or treat brewing wastewater is a problem that is yet to be easily solved.
The contaminated slurry waste streams formed by breweries have excessive levels of biochemical oxygen demand and chemical oxygen demand (BOD and COD) caused by high levels of sugar and alcohol, low pH, and excessive levels of suspended solids. If untreated, brewery wastewater has the potential to be corrosive and cause a slew of other pollution issues. For instance, wastewater causes nutrient pollution, leading to things like algae blooms in rivers, which eventually affects the amount of oxygen in the water, which in turn affects the fish. If wastewater doesn’t meet specific discharge requirements or regulations, industries are subject to serious penalties.
Some municipalities fine for slurry waste violations on a flat scale, but other municipalities break fines down based upon three separate offenses:
- COD level
- pH level
- Suspended solids
Industries will be fined separate amounts for each of the three levels of violations of the three offenses. However, if they can get slurry waste below threshold for any of the requirements, their fines for that offense will disappear.
The problem brewery wastewater is that there isn’t one simple, effective way to lower BOD and COD levels and a way to filter out the total suspended solids (TSS). Centrifuges resolve a fraction of the problems, while filtering methods that are usually effective for slurry don’t work as well with the unique slurry from a brewery.
High feed rates of an oxidizing agent will likely help solve these problems. A step between the oxidizing agents and the filtration may prove beneficial, too. If the particles are conditioned via the addition of flocculating agents or coagulation, this may allow for filtration to perform better. Small breweries can talk to the city to find out their options for utilizing their wastewater treatment facilities. Often, brewery wastewater is treated aerobically at a treatment plant. Blowers aerate the water which promotes bacteria to consume nutrients (BOD). Other byproducts can be hauled away as fertilizer.
If you have any questions, we’d love to help you determine the best option for your unique wastewater. In the meantime, breweries should begin tracking usage to determine the amount of wastewater generated each month.