Tarac Technologies makes its marc on the wine industry

A sustainable way to dispose of winemaking residues

Established in 1929, in the heartland of the Australian wine industry, Tarac Technologies provides environmental solutions to the wine industry by the disposal of winemaking residuals including grape marc (left over skins and seeds), filter cake (perlite and diatomaceous earth used as a filtration aid), lees and distillation wine, centrifuge de-sludge and tank washings.

According to Ira Pant, project manager (environment and sustainability) at Tarac Technologies, if not dealt with appropriately these residuals can lead to significant environmental problems.

"Increases in greenhouse gas and alcohol emissions; odour from the decomposition of the marc; soil and surface water contamination with acidic leachates; breeding vermin, vinegar flies, maggots and potential fire hazards are all risks," she says.

"Tarac currently processes approximately 100,000 tonnes of grape marc, in excess of 35 million litres of distillation wine, lees and de-sludge and 5000 tonnes of filter cake to recover grape alcohol, brandy and tartaric acid."

"The closed loop process ensures maximum utilisation of wine industry residuals and our own by-products are treated to create new sustainable uses."

In 1975, Tarac invested in a joint venture called North Para Environmental Control (NPEC) in the Barossa Valley with the aim of managing the effluent generated from four wine industry businesses, namely Tarac Technologies, Penfolds, Kaiser Stuhl and Tolley Scott and Tolley. The property is now jointly owned by Fosters (70%) and Tarac (30%), and is used to convert liquid winery effluent into irrigation-quality water for agricultural use.

In the early 1990s, NPEC invested in a new treatment method and an experimental covered anaerobic lagoon (CAL), which successfully reduced the biological oxygen demand level by 90% and allowed the treated effluent to be irrigated to pasture. According to Ira Pant, the CAL had been progressively upgraded until 1999, when a substantial upgrade was undertaken to increase the capacity and efficiency to handle the increasing volumes of wastewater.

"Despite the ongoing and steady improvement in wastewater processing capacities and technologies, the rapid expansion of the wine industry over the last 10 years has seen resultant increases in winery effluent," she says, adding that this has been matched by constant reviews and tightening by the EPA of environmental standards and monitoring requirements.

In early 1999, the NPEC board reviewed its future operations and decided to upgrade the effluent management process in an environmentally sustainable way. The upgrade to a Lo BOD wastewater treatment plant was completed in early 2002 with commissioning completed in October 2002 at a cost of $4 million. Since then the treatment plant has successfully treated and irrigated increasing quantities of winery wastewater.

In addition, stormwater harvesting from the Fosters (formerly Penfolds) winery site has added an additional 60 mL of dilution water to improve the quality of water produced for irrigation.

"In January 2005, we decided we wanted to find a better way to utilise the recycled water so a decision was made to undertake trials for investigating the impact of winery waste on vineyard irrigation. This led to the establishment of the Hudson trial site where a block of Shiraz grapes are currently being irrigated using treated winery wastewater. The work is being overseen by the South Australian Research and Development Institute and so far the results are encouraging," says Pant.

"As the demand for irrigation continues to grow, treated winery wastewater demand is also on the rise. Due to the drought this year, NPEC has had increasing enquiries from neighbouring vineyards for its treated water to supplement the restrictions in traditional irrigation water."

"Tarac are confident that ultimately all winery waste processed at NPEC will be returned to the vineyard in the form of high-quality irrigation water. This will achieve the ultimate closed loop solution and minimise the impact on the environment."