Survival of the fittest: Prokaryotic communities within a SWRO desalination plant

Abstract

Water scarcity is known to affect 40% of the global population. By 2030, it is estimated that 700 million people will potentially become displaced due to drought. Seawater reverse osmosis (SWRO) desalination is recognised as one of the most cost effective and efficient methods to produce freshwater. However, biofouling of the SWRO membranes is detrimental to the efficacy of the desalination plants. In this study, the bacterial community composition within the pre-treatment system at Penneshaw SWRO desalination plant (Kangaroo Island, Australia) and the biological fouling parameters on the SWRO membranes were characterised. Membrane autopsies were undertaken on stages 1 and 2 positioned membranes that were operational for two and four years. Results showed that the pre-treatment system allowed for the removal of microorganisms from the water, however niche communities were able to establish and proliferate within the plant due to environmental adaption. The communities associated with the SWRO membranes were stable and had the ability to flourish on the membranes within biofilms. This study provides insights into the community structure within the pre-treatment system of the desalination plant, as well as on the SWRO membranes and examines how they impact on the performance of the plant.