Quantifying the efficacy of capturing microplastics in treated wastewater
thesis
posted on 2023-06-06, 23:39authored byMitchell Vieth
Marine pollution is a global issue with plastics, particularly microplastics, of particular concern. One key pathway for microplastics into the marine environment is through household and industrial wastewater. Following a major nurdle release from the Warrnambool wastewater treatment plant in 2017, a series of new screens were installed specifically to capture plastics from the wastewater inflow and outflow streams prior to and following water treatment. This study aimed to assess the efficacy of the treated wastewater 1 mm rotating drum screen. Plastics captured by the screen were identified from non-plastics using ultraviolet and royal blue fluorescence. It was found that the rotating drum screening system is effective at removing plastics from the wastewater. A total of 214,697 individual plastic items were identified from 84 ML of treated wastewater across twelve 8-hour sample periods. It is estimated that under similar flow conditions, approximately 38,973,149 individual plastic items would be prevented from entering the marine environment each year. Ninety six percent of plastics emitted blue fluorescence under ultraviolet light. The exact chemical makeup of these fluorescing plastics is currently not known. The number of microplastics plastics hidden within fat balls and other organic material captured by the screening system has also not yet been fully quantified, but preliminary findings indicate that the fat material acts as a storage sink for microplastics in treated wastewater.
History
Pagination
52 pp.
Open access
No
Language
English
Degree type
Honours
Degree name
B. Environmental Science (Hons)
Copyright notice
All rights reserved
Editor/Contributor(s)
Mondon, Julie
Faculty
Faculty of Science, Engineering and Built Environment