Background

Rogue Ale & Spirits is a brewery and distillery in Newport, OR that discharges process wastewater to the Newport City sewer system. Rogue was issued a permit that required their outgoing brewery wastewater to not exceed 2,200 mg/L of BOD; 1,000 mg/L of TSS; and to have a pH between 6.0 and 10.0 as to not overwhelm the City’s treatment system. Previously, the brewery was manually balancing pH in a large baker tank, which required brewers to take time away from producing beer in order to treat wastewater. In 2018, Rogue Brewing approached ClearBlu for a solution that would automate the treatment process.

In 2019, ClearBlu installed a treatment system consisting of 8 main components: primary lift station; wedgewire hydroscreen; dewatering hoppers; automatic pH balancing system; secondary lift station; equalization tank; dewatering screw press; final lift station. This system also contained two ultrasonic flow meters to monitor how much wastewater the brewery was producing – one before the screen and the second after the final lift station to monitor the amount of water being discharged to the City.

System

Wastewater from the brewing process is collected in trench drains that flow to an in-ground high-temperature lift station. This primary lift station pumps the water to the wedgewire hydroscreen that removes fibrous material. The solids drop into a dewatering hopper while the screened water gravity flows into an automatic pH balancing system. The unit adjusts the pH in wastewater up and/or down to the required pH range. Once the water is pH balanced it flows into a secondary in-ground lift station that pumps that water into a large equalization tank. Coagulant is dosed in-line to the equalization tank to promote flocculation of small solids. The equalization tank is equipped with volume multiplying eductors that continuously mix the tank. A diaphragm pump is used to pull water out of the equalization tank and to the screw press. Polymer is dosed into the mixing tank in the screw press to further help in solids removal. The wastewater is run through the auger like screws of the screw press, and the dewatered sludge is collected in a hopper to be disposed of with other brewery waste. The final component in the treatment system is an above-ground lift station that pumps the treated water out to the sewer.

Results

Treated wastewater was within the required pH levels and the Brewery saw a 95% reduction of solids and a 20% reduction of BOD.