By: Alyssa L. Ochs
It is common knowledge that wineries produce a significant amount of wastewater. Still, it’s imperative to understand your winery’s wastewater characteristics to choose the right solution. Fortunately, many eco-friendly options are available now to help wineries reduce their environmental impact while using water. These options can also help you stay within compliance regulations without much labor, eliminate the need for extensive pond dredging, address water reclamation concerns and recycle water quickly and effectively.
This article will cover best practices, recycling, monitoring, cleaning, sanitation and technologies for wastewater management to guide wineries in choosing the best options for their operations.
Traditional and Modern Wastewater Solutions
Technologies used for winery wastewater typically fit into four categories: physiochemical, biological, advanced oxidation and membrane. Physiochemical technologies include precipitation, coagulation, sedimentation and electrocoagulation methods. Aerobic biological technologies include membrane bioreactors and conventional activated sludge process methods, while anaerobic biological processes feature anaerobic sequencing batch reactor methods. Advanced oxidation methods are sulfate radical- TiO2- or ozone-based, while reverse osmosis is used for membrane technologies.
Types of treatment systems applicable to wineries include lagoons to treat wastewater organic material and artificial wetlands using plants to break down organic matter. There are also bioreactor methods with small footprints to maximize usable vineyard space and conventional activated sludge that features a mix of wastewater and oxygen to ensure that microbial organisms break down organic matter.
Yoni Szarvas, the founder, president, CEO, and chairman of AquaBella Organic Solutions, told The Grapevine Magazine about several wastewater approaches available to wineries today. Founded in 2008, AquaBella is a socially responsible company headquartered in Sebastopol, California that delivers the power of naturally beneficial bacteria to reduce water pollutants and create higher crop yields. The company aims to reduce the need for chemical fertilizers, boost agricultural lands’ long-term sustainability and fertility and break down organic pollutants to clarify water.
Szarvas explained that traditional approaches to wastewater management typically involve using a wastewater pond or series of ponds to remove contaminants until the water quality standards are met.
“A more modern approach is to use a modular treatment system, which potentially is more cost-effective than surface water ponds,” Szarvas said. This approach involves installing prefab above-ground tanks instead of excavating wastewater lagoons. Many wineries use wetland reclamation technology, which has the added benefit of acting as a carbon sink and minimizing CO2 release into the atmosphere.”
Characteristics of Winery Wastewater
Winery wastewater typically has a low pH of three to four, nitrogen levels of up to 500 milligrams per liter, a high biochemical oxygen demand (BOD) of up to 10,000 milligrams per liter and high turbidity. The characteristics of wastewater will vary by the season but must always be kept in mind by vineyard owners to prevent foul odors and protect water quality. Some wineries turn to companies like Specialty Treatment Solutions (STS), to devise customized wastewater treatment plans based on wastewater characteristics. ClearBlu Environmental and BioMicrobics, Inc. are additional companies that serve the winery market with wastewater treatment solutions.
Effluents and Contaminant Burdens
Wine industry wastewater is primarily produced from cleaning equipment and machinery, such as tanks, destemmers, pumps, tubes and filters. Wineries also produce wastewater when employees wash fermentation tanks, bottles and barrels. Some wastewater comes from spillages that happen during winemaking transfers, too. Harvesting, cellaring and bottling processes all produce wastewater, and multi-step treatments are typically required regardless of whether you choose traditional or new-technology methods.
Approximately half of a winery’s annual wastewater comes from harvesting, a time of the year that only lasts a few weeks. Even worse, harvest wastewater has the highest contaminant burdens as employees work long days pressing grapes, cleaning equipment and handling accidental spillages. Cellaring-generated wastewater is produced during the wine’s maturation phase, when fermentation tanks are cleaned and wines are clarified cold before bottling. Effluents from cellaring wastewater tend to have a high pH. The lowest wastewater contaminant burden comes from bottling processes, as employees clean bottles and disinfect equipment during their workdays. The type of wastewater produced will dictate the appropriate treatment method, depending on whether it will be discharged into the public sewer system, released into a natural waterway or used to irrigate the vineyard.
How to Manage Winery Wastewater
The first step in treating winery wastewater is to address the solids since solids may hinder the rest of the treatment processes. During pretreatment and neutralization, make sure to adjust the pH to ensure effluents can be discharged properly. Once liquids are separated from solids, the primary treatment process should eliminate around 30 to 40 percent of organic matter. Secondary treatment processes dissolve nutrients and organic matter, typically using nitrogen and phosphorus. Advanced treatment options are available for wastewater that will be reused within the winery’s operations.
Good water and wastewater management can reduce operations costs, time and labor when carried out properly. Along with improved production efficiency and lower disposal fees and surcharge costs, wastewater practices can also help you promote your winery as a sustainable business in the local community. There is a growing demand for environmentally-friendly production, and managing wastewater is a practical and tangible way to stand out in a crowded marketplace while also staying ahead of changing water regulations and risks of natural disasters.
Recycling and Reusing Wastewater
Vineyards can reuse wastewater for irrigation and other purposes after performing advanced treatments, such as disinfection through ultraviolet radiation and ozone-based oxidation. After the second treatment, employees filter effluent using a granular sand bed and then proceed with ultrafiltration or another membrane-filtration process before reverse osmosis.
As Szarvas from AquaBella pointed out, vineyards generally reuse wastewater once contaminants have been removed.
“Land application is a common reuse of this water which helps keep costs down, especially for smaller vineyards,” he said. “There may be additional opportunities to recover energy from wastewater and solid waste, such as pomace in the form of biogas.”
Monitoring, Cleaning and Sanitizing Processes
Keeping up with wastewater management and monitoring cleanliness and sanitation is always the best approach to any wastewater plan. Try to work ahead as much as possible to keep up with these tasks.
“This means having good sanitation practices in place prior to treatment and exploring options that minimize the use of cleaners that will either interfere with the wastewater treatment process or add to the waste stream,” said Szarvas from AquaBella. “Regular testing of the wastewater for common vineyard contaminants, such as nitrogen, salinity and organic matter as indicated by biochemical oxygen demand are used prior to land application of the treated wastewater.”
Choosing a Wastewater Management Strategy
Of course, there are many factors to consider before deciding on a wastewater treatment system, including local and state regulations that define the maximum levels of biochemical oxygen demand, nitrogen and salinity for disposal on land. Cost is a significant consideration, especially labor prices and costs for chemicals and maintenance time. As a winery owner, you’ll also need to think about how much land you have to dedicate to wastewater management, the capacity of your staff to handle wastewater tasks and creative ways to repurpose wastewater to your advantage.
Szarvas from AquaBella explained to The Grapevine Magazine that there is no one-size-fits-all treatment option for all vineyards.
“Vineyards are in a unique position due to the seasonal nature of the wastewater generated,” he said. “Only during ‘crush,’ when grapes are harvested and pressed, do they generate a significant amount of wastewater. Wastewater treatment approaches need to be cost-effective for a large amount of waste for this short period of time. A treatment approach that has the capacity necessary to meet this need is essential.”
For example, AquaBella Organic Solutions makes a low-cost microbe-based water treatment product, AquaBella Bio-Enzyme. This product works without having to build on or improve existing water treatment infrastructure and can significantly shorten the timeline required for nitrogen, BOD and organic matter treatment. This allows a higher volume of wastewater to be processed more rapidly.
“AquaBella Bio-Enzyme also works in a wide range of pH and salinity conditions,” said Szarvas. “AquaBella Bio-Enzyme can rapidly break down and remove organic matter in process water, resulting in improved dissolved oxygen, reduced BOD and volatile dissolved solids while helping to control odors.”
Looking ahead to the future, winery owners must pay close attention to energy and material prices when addressing their wastewater concerns. There is a significant need for economical solutions to serve the increasing needs and limited budgets of small and medium-sized wineries. In-demand innovations being researched include technological solutions to ensure winery wastewater is reusable at food-grade quality, compact equipment to minimize the land footprint and anaerobic treatment solutions that produce methane to become at least partially self-sufficient.
In the meantime, winery staff members can do their part to track and monitor water use, fix leaks and use the right tools for the job when handling water. Simple and no-cost best practices, like following established procedures for cleaning and sanitizing and providing employee training and incentives for proper wastewater management, can go a long way in improving wastewater disposal, usage and quality at a winery.
