Salt reduction in wineries (TEFF)

Tarac Technologies administers the Tarac Environmental Future Fund (TEFF). The initiative was introduced to encourage innovative environmentally sustainable solutions for management of winemaking residuals. Tarac awarded a TEFF grant for a collaborative project between two premier South Australian wineries, Yalumba and Rosemount Ryecroft (Foster’s) and JJC Engineering Pty Ltd. Tarac contributed $15,000 to this project and this was supplemented with $5000 from the Grape and Wine Research Development Corporation (GWRDC). This project investigated processes for minimising the potassium content of winery wastewater. Wastewater treatment facilities at Yalumba’s Moppa and Foster’s Ryecroft wineries successfully remove BOD from wastewater. But salts remain. Both companies are concerned that the salt in the treated wastewater may limit the reuse of this water in the vineyards.Investigations conducted at Yalumba’s Moppa winery demonstrated that initial rinsewater discharged from tanks used to process wine immediately after fermentation contribute a significant wastewater load:

13% of site wastewater COD load, in 1.4% of the total wastewater flow during vintage
Adds 110 mg/L potassium into wastewater during vintage.

Also, at Moppa and Foster’s Ryecroft winery, initial rinsewater from tanks used for cold stabilisation of wines was shown to produce small volumes of sludge containing up to 390 g/L of tartrate.

Segregation of these initial rinsewater streams, and diversion to Tarac Technologies appears to provide a “win-win” opportunity by:

Removing highly concentrated organic load from the onsite wastewater treatment plant, freeing up capacity for other winery wastewater.
Reducing potassium concentration in treated winery wastewater during vintage by around 100mg/L.
Providing Tarac with a rich tartrate and potassium feedstream for recovery.

During 2006 and 2007, Ryecroft personnel developed equipment and procedures to reduce, and reuse sodium-based cleaners. This resulted in an impressive 60% reduction in the use of sodium-based cleaners at the site in 2006/07.

Analysis of “spent” caustic wash at Ryecroft showed that maximum sodium concentrations of 4,200 mg/L were achieved. The achieved concentration was lower than expected, and was interpreted to indicate that there is potential to improve reuse systems, to produce a lower volume of a more concentrated “spent” caustic wash for disposal. A more concentrated “spent” caustic wash may also carry more organics, increasing the value of the waste stream to Tarac.

JJC, in partnership with Tarac and the participating wineries, were able to demonstrate the benefits of cleaner production activities that benefited all parties.