Winter performance was a concern for this New England fruit juice processor. The company’s greatest production levels occurred in the fall and winter months, resulting in the heaviest BOD (biological oxygen demand) and MLSS (mixed liquor suspended solids) loads occurring at the worse possible times. Cold weather increased heat loss, reduced biological activity, slowed settling, and caused substantial ice build-up in its aerated basins.
In 1983, the company installed eleven (11) AIRE-O2® aspirator aerators from 3 to 15 hp (2.2 to 11 kW) sizes into its activated sludge basin. Icing problems immediately disappeared. The chief operator said, 'Due to lower heat loss rates with the AIRE-O2® units, we have more biological activity and improved settling. There’s been a noticeable BOD reduction in the back ponds because of the warmer influent coming from the AIRE-O2® aeration basin.'
The processor was also impressed with the aerator’s minimal maintenance requirements despite very high MLSS (10-14,000 mg/l) in the wastewater. In later years, more AIRE-O2® aerators were purchased and installed in the plant’s aerated lagoons. The processor likes the aerator’s sub-surface operation. The old surface splasher type aerator’s aerosols had literally corroded nearby buildings’ exteriors. The processing company has received the prestigious 'Ecology Flag' award by the American Institute of Manufacturers for its exceptional environmental achievements. Congratulations!