Algal and cyanobacterial blooms incur current treatment challenges such as high operational cost, disinfectant by-product formation, and the requirement to separate oxidants from solution after the oxidation. Advanced oxidation methods, such as cold plasma activated bubbles (CPAB), have the potential to overcome the current challenges . CPAB are bubbles containing partially or fully ionised gas that utilise the ambient condition of gas and an electric discharge to produce and deliver highly reactive oxygen and nitrogen species, such as ozone, hydrogen peroxide, hydroxyl, superoxide, and nitric oxide radicals. This project will examine methods to optimise the application of CPAB across a range of algal and cyanobacterial species to increase its technology readiness level.

PhD Thesis underway by Angelina.

This project determined disinfection by product contribution from chlorination of algae.

Honours/PhD Thesis completed by Adam John Tomlinson in July 2018.

This research identified and validated the impacts of particle-pathogen association on the disinfection of various microorganisms in the treated wastewater effluents.

PhD Thesis completed by Charndeep Chahal in April 2020.

Sunlight-induced degradation is an important removal mechanism for some contaminants and has been commonly overlooked as a removal mechanism in wastewater systems in the past. This project aims to predict the direct sunlight-induced degradation, or direct photolysis, of contaminants of emerging concern in wastewater treatment lagoons to improve monitoring and removal efficacy of the contaminants, and thereby enable water operators and management to perform ecological risk assessment and make better management decisions.

Honours Thesis underway by Michelle Um.

This project developed an understanding of the occurrence of regulated and emerging disinfection by-products (DBPs) in drinking water in Southeast Queensland (SEQ). This was achieved through the characterisation of natural organic matter of several SEQ source waters and through exploring strategies for halide and organic matter DBPs precursor removal from water, and examining the effect of these removal strategies on DBPs formation.

Honours Thesis completed by Kalinda Watson in October 2014.

This project addressed the removal rate of ammonia by microorganisms and designed a pathogen survey to establish the level of contaminants present within influent water at the Aquifer storage and recovery site at the Aldinga Aquifer.

Honours Thesis completed by Kimberly A. Sieburn in November 2011.

This project investigated the preparation and stability of concentrated preformed monochloramine solutions, with the potential application of remote area redosing to maintain disinfectant residual. Various conditions (such as pH and temperature) were investigated for their affect on the formation and stability of high concentrated monochloramine solutions, and the optimum conditions determined. The effect of redosing with concentrated solutions on disinfection by product formation were investigated. Overall this project aimed to better understand the constraints on the stability of high concentrated monochloramine solutions.

Honours Thesis completed by Charlotte Andringa-Bate in November 2010.

Source waters contain a class of chemical compounds collectively known as ‘bromides’. Standard water treatment includes chlorination; a process designed to kill harmful microorganisms in source and recycled waters. The problem is that chlorination agents react chemically with bromides to form ‘brominated Disinfection ByProducts’. These bDPBs can contribute to the development of cancer and this led the Australian Drinking Water Guidelines to recommend very low concentrations of bromides in source waters, less than 0.1 parts per million (0.1mg/L). At this level, if any bDBPs subsequently formed during chlorination, their occurrence will be too low to pose a public health risk. Some Australian source waters have higher bromide concentrations, but existing removal methods are expensive and/or do not work very well. The scientists in this team have already synthesised a new bismuth substance (see image) that removed 86% of an experimental bromide from artificial groundwater.

This project will aim to combine the modified bismuth with alum, which is currently used to treat water. If researchers succeed in creating a composite that incorporates bromide removal into existing tried-and-tested water treatment processes they will deliver a cost-effective improvement to water quality and safety. However, it will require clever and careful chemical design to create the new bismuth-alum composite, and to run experiments that will test its ability to remove bromides from source waters. As if that isn’t challenging enough, they also propose to develop a software programme that will predict bDBP formation. If they are able to eventually build a validated model it will be an extremely useful addition to the suite of tools currently used to produce safe, high-quality drinking water.