Successfully Treating Winery Wastewater
Save $135k Treating Winery Wastewater
Many smaller wineries have outgrown their septic tanks, and larger wineries have outgrown their treatment ponds, a BioReactor gives increased capacity at a fraction of the cost of conventional pond treatment systems.
Wineries traditionally treat their wine process wastewater with aerobic (aerated) ponds to biologically degrade the biochemical oxygen demand (BOD). The treated wastewater from these ponds needs to have a BOD of 40 ppm or less (depending on the location of the winery) before the winery can discharge the water to the vineyards for irrigation.
Winery ponds require a large surface area (detention time) to treat the winery wastewater usually between 60-90 days for conservative design. Since the ponds have a large surface area, they need to include the capacity to hold a prolonged rain based on a 10-year rainfall event.
An Alternative Solution
Instead of ponds, there is another way to degrade the BOD down to the levels required for irrigation discharge. The solution is the use of a biological returned activated sludge system also called a BioReactor. A BioReactor is a more efficient biological process than a pond system.
The BOD degradation in a BioReactor process involves a series of tanks either in ground (concrete) or above ground (steel or polyethylene). The oxygen is supplied with blowers and a fixed grid aeration system.
The EQ-Blower provides pre-aeration as well as mixing to the equalization tanks with coarse bubble diffusers. The second equalization tank is for further aeration and mixing as well as the reseeding of the activated sludge from the final clarifiers.
After a detention time of 24-36 hours, the wastewater flows into the clarifier for settling of the solids forming sludge (sludge settling).
The sludge is important since it has a high concentration of the biomass (bacteria) that needs to be returned to the aeration process, hence the name 'returned activated sludge'. Either system will still require an irrigation pond, but there is a significant amount of money that can be saved with a BioReactor system.
The pond system for the facility would have a comparative summary of the expenses of installing a pond treatment system, either clay or plastic lined ponds, the loss in vineyard grape production and other expenditures not usually accounted for by winery owners estimated at $363,900, while the BioReactor system resulted in a cost of $228,210, thus a savings of $135,690 or 37%.
The traditional pond systems to treat winery wastewater requires a good deal of acreage due to the long detention times required for the degradation of BOD to the levels required for irrigation. A BioReactor can save a significant amount of capital costs, increase the wineries wastewater capacity at a fraction of the costs of conventional pond treatment methods. Existing wineries can easily adapt the BioReactor system into their process and new wineries can greatly benefit by utilizing these advantages from the start.