Scientists aim to improve wastewater

2 April 2007

Cleaner wastewater entering New Zealand’s waterways is the vision of two scientists at Rotorua Crown Research Institute Scion, and their work is a step closer thanks to scholarships received by the pair.  

Sarah Addison and Marie Dennis are each working on projects aimed at optimising biological wastewater treatment processes.

Novel approaches to wastewater treatment is a major focus for Scion’s Eco-Smart Technologies group.  This has lead to the development of a patented treatment system which uses nitrogen-fixing bacteria found in industrial wastewaters. These bacteria not only improve water quality but also lower the costs of running a treatment system. To make the technology work, scientists have had to learn more about the key organisms involved in the process.

Sarah Addison, a molecular microbiologist at Scion, has this year started a Master’s thesis through Waikato University looking at these nitrogen-fixing bacteria. She has received an Enterprise Scholarship from the Tertiary Education Commission for her research into a technique that is used to identify, understand and optimise the role of these bacteria in the biological treatment of pulp and paper wastewaters.

“By studying whole communities of bacteria in biological wastewater treatment and pinpointing those responsible for nitrogen fixation we can manipulate these important organisms to give better treatment and ultimately environmental positives.

“Our goal is to transfer this knowledge to end users in the wood processing, food processing and biorefinery sectors. My approach can also be applied to many other different environments, such as soils,” she says.

A full-time Scion employee, the scholarship has allowed Ms Addison to devote herself full time to the research. She has been working on the project since August last year and will complete her thesis within 18 months.

“I’m really enjoying the work. It’s practical, you can see an end goal, and it’s research that can help solve a real problem,” she says.

Fellow Scion scientist Marie Dennis is involved in a project team focused on optimising and pre-commercialising the nitrogen fixation wastewater treatment process from an operational viewpoint.

Mrs Dennis, who is in charge of Scion’s advanced bioreactor facility, recently returned from Australia where she was on a Queen Elizabeth II scholarship to study at Melbourne’s La Trobe University.

Her work at La Trobe University was to learn research methods to microscopically identify bacteria in the nitrogen fixation treatment system and to establish important collaborative links with the University.

“There is no other organisation in New Zealand undertaking work on nitrogen-fixing bacteria in pulp and paper wastewater, so there is a lack of information available on the classification of these bacteria and their role in good performance.

Mrs Dennis says that her work at La Trobe has given her the tools to identify many of the bacteria present in wastewaters and a bonus was highlighting the presence of a bacterium which appears novel to nitrogen-fixing treatment systems.

“There’s a lot of work taking place at Scion looking into wastewater treatment, and its exciting to know that what we are doing will directly help industries to reduce the impact they have on the environment,” Ms Dennis says.

Scion is a Crown Research Institute which is dedicated to creating the next generation of sustainable biomaterials.