Microbiology holds the key to better wastewater treatment

Everyone wants to pay less for wastewater management. That’s the rationale and motivation behind an AGWA-funded project looking at ways to make winery processes more effective and efficient.

For the past year a University of Adelaide team led by Associate Professor Paul Grbin and chief investigator Dr Kathryn Eales has analysed samples collected regularly from four Australian wineries with biological wastewater treatment plants, while also keeping a watching brief on 32 others.

The aim is to integrate commonly collected information, such as chemical practices, with a detailed study of the microbiology underpinning all the processes and look at this in terms of actual operational practice.

The ultimate goal is to develop guidelines or new tools that can be adopted in the winery. The first stage has involved getting a handle on exactly what’s going on.

“From early December to the end of April we sample the four winery plants every fortnight and do a full suite of chemical analyses and micro analyses, which hasn’t really been done before,” A/Prof Grbin said.

“Then we look specifically at what’s happening in terms of the populations of micro-organisms across that peak period and then, post-vintage, look at individual plants.

“We’ve been through one full cycle of that analyses, from pre-vintage to quiescent period to now, where we’re in the peak period again, and what we’re seeing is changes in the populations of micro-organisms depending on the time of year and depending on the plant.

“Through this project, and work we’ve done previously, we’ve that noticed that a group of organisms seems to be more problematic than others and so we’ve brought in a PhD student who is specifically looking at this set of organisms.”

The four wineries – Casella and Southern Estate Wines in Griffith, and Yalumba’s Oxford Landing and Pernod Ricard’s Rowland Flat winery in the Barossa – are part of the project because of the nature and scale of their wastewater systems and “because we know they are really interested in learning how to do things better.”

The research team also includes two consulting engineers from JJC Engineering and a CSIRO environmental toxicologist. Others at the CSIRO are providing analytical services.

The results to date are not surprising but are very instructive.

“We expected to find quite a broad range of microbes present in winery wastewater and that’s indeed the case; there is diversity and there are significant differences between the treatment plants,” A/Prof Grbin said.

“So the results confirm some of our hunches with actual data.

“One new approach we’ve taken is using meta-genomic analysis to have a powerful tool to investigate the variations in populations and enable us to compare across different plants.

“That data is brand new; it’s never been collected for winery wastewater before. For us its pretty exciting to see how that might pan out and give us some clues about how to tweak the systems to make them perform better.”