John Haugen is Co-Founder & Sustainability Strategist at Third Partners, a sustainability advisory firm with a specialty in the brewing space. Here, John gives a primer on how to conduct due dilligence for wastewater management, as well as strategies current breweries can utilize.
Breweries are increasingly focused on wastewater management. Municipal water treatment authorities across the country are charging breweries additional costs due to the high-strength wastewater streams from brewery processes. Breweries are also realizing that they affect water quality in their communities and are interested in making a genuine improvement.
These economic and environmental forces work together to make brewery wastewater treatment systems an important strategy to consider in any new brewing operation. Even for those already brewing, wastewater treatment on-site can produce positive ROI by increasing operational efficiency. Below are questions to consider, followed by common wastewater management strategies and other resources.
Questions to consider when starting a new brewery:
- Before picking a site, investigate matters such as sewer capacity and discharge limits in the area.
- Are there existing or planned wastewater surcharges in your area? Consider county, city, and state rules. Common requirements include: neutralize pH levels, removal of solids, and biological treatment.
- Talk to other local breweries, especially those with brewing operations built recently. Are they subject to new requirements that have not yet been issued to existing facilities? If you are just starting out, any new guidelines may impact your business in a way that older breweries have been able to avoid.
Strategies to treat wastewater:
- If you’re currently operating your brewery, do you know the average total suspended solids (TSS), biological oxygen demand (BOD), chemical oxygen demand (COD), and pH of your wastewater? When you do know, also know how each is changed based on process - clean-in-place (CIP), brewing, and packaging each differently affects the quality and levels of contaminants in wastewater. You can learn more about these elements here.
- Side streaming. The vast majority of BOD can be found in highly concentrated waste streams such as yeast, trub, and waste beer. Learn more here.
- Physical screening. This can take the form of screening solids, settling tanks, and flocculation for large, small, and dissolved solids, respectively.
- pH neutralization. Adding caustic or sulfuric acid in mix or trim tanks can neutralize pH to safe levels before sent to the local wastewater system. A buffering tank that combines caustic and acid process wastewater can neutralize pH over the course of brewing and CIP activities.
- Biological Digestion. Both anaerobic and aerobic digestion are feasible strategies for wastewater treatment. Anaerobic is more expensive but provides renewable energy from biogas, low operating costs, and can fit within a small footprint. Aerobic digestion requires a significant footprint and requires high energy use and operating costs.
Something to keep in mind - as you reduce overall water usage throughout your brewing process in order to reduce costs and freshwater use, wastewater quality can actually decrease. By applying less freshwater as an input, the concentration of BOD, COD, and TSS per unit of wastewater increases. Keeping an eye on these levels as you change your process is important to maintaining your system.