Oil-free screw blowers provide compressed air to process effluentProblem: Operators of the wastewater treatment plant in Versmold, Germany, sought an updated energy source to process effluent. The 2.2 mgd plant treats 60 percent high-strength wastewater from meat processors containing above-average quantities of phosphate. The treatment and measurement technology, process controls and compressed air technology had to quickly measure the influent contents and respond accordingly.Solution: Two Atlas Copco ZS 55+ oil-free screw blowers with variable-speed drives supply energy-efficient compressed air to process effluent. Nitrification and denitrification take place simultaneously in two aeration tanks. The aerobic process is first supplied with oxygen via
