How to treat winery waste water

Steve Barry, President of AQWA, recently traveled to Napa to do some firsthand research on treating process water from wineries. Wineries are tricky to design for due to the highly variable and seasonal nature of the wastewater stream.

He shared the following write-up about his experience shortly after returning home. 

"For some time, Orenco has been informing us that AdvanTex systems will work well for winery waste. It made sense to me. Wine is easily and readily digestible by bacteria and they grow readily on it (as do humans...). As you all know, AQWA doesn't jump into anything too quickly, and prefer to let others be guinea pigs. California dealers began selling AdvanTex to wineries a number of years ago, so they have learned a few things, some the hard way. Recently, I've decided it was time to go kick the tires on a few systems and our recent sales trip to Orenco was to be that excuse. Flight (snow) issues messed with the overall business trip, but Becky and I were able to at least get out to see the winery systems. 

We met with Bill Beck, the area sales rep with Orenco early Saturday morning. The local news was complaining about how cold it was...headshake....it was 45 and warming to 55 later in the day. Perfect weather considering we left NC in 20 degree weather and snow on the ground.

 We chatted and waited on Gary McCollum, whose company installs and operates these systems. Once Gary got there, we all took off and headed to our first winery visit. After driving through the rolling hills covered in grape vines we arrived at the Progeny Wines vineyard owned by the Woolls family. Gary operates a variety of treatment systems in the area. He is very pleased with the AdvanTex he operates and tries to steer customers that way when he can. He is particularly fond of the TCOM panel and it's automation, and the service that Bill and Orenco has provided him. His crews visit the systems quarterly for check-ups and twice annually for real maintenance activities.  

The system they have is designed for 1,600 GPD of winery and sanitary waste. According to Gary, co-mingling the waste streams makes it a bit easier on the treatment system since there are plenty of days that the winery is not processing grapes. During those days, it's nice to have at least a little "food" from the bathrooms in the offices and tasting rooms. Effluent from the winery production is expected to be about 2,000 BOD. It runs via gravity into a 4,000 gallon septic tank and then to a combined equalization tank. Sanitary waste flows into a 1,500 gallon septic tank into the combined equalization tank.

 This combined flow is pumped out to an aeration tank on a timer controlled basis.  The aeration tank is fairly small at approximately 3,000 gallons and it includes fine bubble diffusers designed and installed by Gary. "Off the shelf stuff, designed to deliver about 35 CFM. We just want to kick start the process with this air." 

There is also a sensor in the aeration tank that continuously monitors the pH of the system. The pH is adjusted automatically via two liquid feed systems. If pH rises above 8, an acid is added, and if pH drops below 6, a base is added, automatically.  Gary indicated that this pH buffering system was one of two keys to a successful system. He indicated that they can have wild pH swings in the process water, and obviously the microbes in the treatment system don't handle these swings well.

Effluent then flows into a 35' two stage AX MAX system. I inspected the unit and growth on the textile was even and obviously heavier in the first stage than the second.  The system has been installed for two years and growth looked good and healthy. There were a few filter flies in the system, which is not terribly surprising given the strength of waste incoming. Regulations indicated that they must get the effluent to a 30 mg/l BOD and 30 mg/l TSS standard prior to dispersal. Eyeballing the waste in the end of the MAX, I would have estimated it to be hitting that limit or slightly less. Final dispersal is through a two zone subsurface Geoflow Drip system. They didn't know the exact square footage, but the drainfield was fairly small and located on a nearby slope. 

Gary indicated a few pitfalls to be aware of.  First, as stated previously, pH adjustment is vital. He wasn't sure what chemicals they were using as another company handles the installation and operation of the chem feed system.

Secondly, he said the "Lees" of the process needed to be segregated away from this waste stream.  The lees is the sludge from the bottom of the winemaking tanks. Some wineries then pull this lees through a diatomaceous earth filter and this DE, can and will blind the entire wastewater process. There are companies that use the lees for other winemaking processes or it needs to be taken and composted or disposed of properly. Additionally, odor off the aeration tank has been an issue. We've seen this with other activated sludge systems in the residential market, so the fact that water with a BOD as high as being treated here has an issue with odor, is not surprising.

After we took some pictures, asked some questions, looked into some tanks, and made some notes, we packed up and headed to the next winery.

The Gamble family vineyard (...as in Proctor & ____) sits right up next to the Napa river. As a matter of fact, last year the river rose and flooded the site with over 18" of water. This waste stream was a little different in that they do not have a co-mingled system. Waste from the winemaking process is treated by an AdvanTex system. The tasting room and offices are treated with conventional low pressure pipe system.

The layout and flow of this system is very similar to the Progeny vineyard system.  Primary tanks are followed by equalization, then aeration/pH adjustment, and a recirculation tank. There are two AX100 systems on this system that is designed for only 900 GPD. However, Gary warned us "Don't believe it though, when they want to make wine they are going to make wine. We get 3000 GPD on those days, and at other times get nothing." 

Effluent from this system is fed through drip irrigation directly to the grape vines nearest the system. They store treated waste and the owner activates the irrigation systems manually. Effluent applied to the grapes has to meet a less than 120 mg/l BOD standard.  This system was also performing well, seemed to be in a good shape and properly sized if not maybe a little oversized. The owner met with us for a few minutes and said he was very pleased with the system and the service that Bill and Gary had delivered.  

After finishing up our notes and pictures, and getting some good advice on a few wineries to hit for a tasting....hey we came all this way...we said our goodbyes, hopped in our rental and left.  All in all, it was a very good trip and a great learning experience. There are a couple of twists that AQWA will likely employ utilizing some of the knowledge we've gained over the years, but our recommended designs will be quite similar to what they are doing in Napa.  Now it's up to us to go out there and spread the good word and see how we can help our local wine industry!  "

AQWA is looking forward to bringing the proven Advantex treatment technology to the mid-Atlantic's growing wine industry as a low-maintenance, dependable onsite wastewater treatment system.

Orenco has a lot of really good winery case studies on their page check them out HERE.