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Aeration system removes pungent bouquet
One of the most important features of a wine is its aroma. Unfortunately, wineries sometimes have to combat olfactory ordeals in order to keep their facilities smelling pleasant.
Several years ago, the wastewater evaporation lagoons of a Madera, Calif., winery developed odor problems. The facility’s wastewater is collected and pumped to two main lagoons for evaporation, percolation, and sprinkler irrigation. This wastewater contains large amounts of organic matter; the large organic loading results in high biochemical oxygen demand, and over time, the lack of oxygen in the wastewater allows anaerobic bacteria to turn septic and cause odor problems.
To solve these issues, three 4-in. Mazzei Injectors were installed; a single 30 hp centrifugal pump powered them. Water from one lagoon is pumped through the injectors at a rate of 1105 gal per minute, providing an air injection rate of about 135 standard cubic feet per minute. The aerated liquid from each injector is discharged into the bottom of the lagoons. The strategic location of the injectors with respect to the lagoons’ influent/effluent lines, in addition to the equalization line water flow, provides efficient circulation of aerated water through both lagoons.
This system provides enough recirculation to turn over the total volume of both lagoons every 1.5 days. The air is uniformly dispersed under pressure, resulting in maximum oxygen transfer. The dissolved oxygen residual is maintained throughout both lagoons (dissolved oxygen readings from various sample locations range from 0.3 ppm to over 10 ppm), and the odor problem has been eliminated. This system was installed in 2001, and it continues to provide reliable, low-maintenance operation.