Open ponds are far from the only option for processing and treating wastewater at a winery, but they are one of the most effective and affordable choices. Other options may work nearly as well or provide other benefits specific to the site chosen for the winery. For a comprehensive water treatment approach, that produces clean discharge for a wetland or irrigation, you may need to combine more than one of the following treatments.
Above vs Below Ground Processes
In general, you’ll need an above ground storage structure like a pond to use aerobic treatment methods. It’s hard to pump enough air and aerate liquids held in closed or underground tanks. If you’ve chosen an anaerobic treatment method instead, then a buried or enclosed tank is acceptable or even desired. You can still use surface ponds for anaerobic digestion by using covers or flexible biodigester caps to control access to oxygen without having to excavate under the surface of the soil.
Septic systems, similar to the ones used for residential and commercial sewage, are also available for managing wastewater from wineries. However, the high concentration of suspended solids and sludge in winery wastewater makes it difficult to discharge through leach fields and similar septic system designs. The openings in the leach pipes or trenches easily become clogged by these solids. Tree roots are also attracted to the sugar and nitrogen in the wastewater and tend to infiltrate these drainage systems. Septic systems for winery wastewater must be large, expensive, and maintained on an annual basis to prevent clogging and root damage. In general, surface ponds are a more affordable and effective choice.
Various Types of Ponds
Treatment ponds may look similar, but they can vary greatly in the actual mechanisms used for water treatment. Some ponds are still and rely on chemical additives to settle out particles and stabilize the water’s pH. Other ponds are highly aerated and circulated to let invisible microbes break down the various components of the wastewater. Most ponds will benefit from the addition of screens and filters at least to capture concentrated solid waste before it can settle at the bottom. Settling tanks also provide a powerful sludge reduction action. Some ponds only capture wastewater after it’s been reused for irrigation so it can’t runoff into waterways or nearby properties.
Bioreactors are intensive water treatment options that rely on an immersed membrane that encourages extra microbial growth for faster waste processing. They’re often built around raised tanks or in-ground ponds complete with both immersed membranes and flexible upper covers. This creates an anaerobic environment to tightly control the microbes flourishing in the mixture. Bio reactors work well for highly concentrated wastewater, but few wineries need to spend the money required for bioreactor features just to reach acceptable quality for discharge or irrigation reuse. Try a more affordable option with aeration instead, unless you’re sure you need the extra processing power of a bioreactor.
The most affordable and effective way to manage most winery wastewater is to mix oxygen into the water with aeration equipment. Aerobic digesters inside of tanks or other enclosed spaces are also common, but they have a far more limited volume. Aeration works well against salinity but takes longer than other methods to reduce the total levels of unwanted compounds. Sugar breaks down fastest when the wastewater is aerated though, which can control smells and make neighbors happy.
Solids Control with Screens and Filters
All other types of winery wastewater treatments benefit from combining with some kind of extra control for solids. Other types of waste often feature far fewer solids than winery byproducts, especially when fruits are being crushed for their juice. Pulling the stems, seeds, and skins out of the wastewater is easily accomplished with a wide range of screens and filers. Bags, boxes, screens, conveyors, and rollers are all available to remove valuable pomace for reuse as fertilizer or animal feed. Aerated ponds, in particular, benefit from screening and filtering since they can easily fill with sludge and require extra dredging without it.
On-site vs Transport Costs
If you have an option to discharge water somewhere nearby in a municipal treatment plant, you may wonder how the costs stack up against on-site treatment. Most wineries will find that even short trips to treatment plants will cost more in the long run due to the volume of water produced. Even large tanker trucks can only hold a few thousand gallons of water at a time, but each gallon of wine can generate 5 to 15 gallons of wastewater. That means a producer making only 10,000 gallons of wine a year will easily need transportation for 50,000 gallons of wastewater at minimum. The treatment pond would only need to hold a fraction of that total amount at once, making it more affordable than you might assume to install.
Don’t let costly discharge fees or long distances to treatment plants stop you from starting a new winery. It’s perfectly possible to handle all the water treatment necessary on-site for most wineries, as long as the right systems and storage equipment is used. Design your new ponds with our help today by contacting us at BTL Liners.