Upgrading a large and centralised municipal wastewater treatment plant with sequencing batch reactor technology for integrated nutrient removal and phosphorus recovery: Environmental and economic life cycle performance
Upgrading a large and centralised municipal wastewater treatment plant with sequencing batch reactor technology for integrated nutrient removal and phosphorus recovery: Environmental and economic life cycle performance
Although nutrient removal and recovery from municipal wastewater are desirable to protect phosphorus resource and water-bodies from eutrophication, it is unclear how much environmental and economic benefits and burdens it might cause. This study evaluated the environmental and economic life cycle performance of three different upgraded Processes A, B and C with commercially available technologies for nutrient removal and phosphorus recovery based on an existing Malaysian wastewater treatment plant with a sequencing batch reactor technology and diluted municipal wastewater. It is found that the integration of nutrient removal, phosphorus recovery and electricity generation in all upgraded processes reduced eutrophication potential by 62–76%, and global warming potential by 7–22%, which, however, were gained at the cost of increases in human toxicity, acidification, abiotic depletion (fossil fuel) and freshwater ecotoxicity potentials by an average of 23%. New technologies for nutrient removal and phosphorus recovery are thus needed to achieve holistic rather than some environmental benefits at the expense of others. In addition, the study on two different functional units (FU), i.e. per m3 treated wastewater and per kg struvite recovered, shows that FU affected environmental assessment results, but the upgraded Process C had the least overall environmental burden with either of FUs, suggesting the necessity to use different functional units when comparing and selecting different technologies with two functions such as wastewater treatment and struvite production to confirm the best process configuration. The total life cycle costs of Processes A, B and C were 10.7%, 29.8% and 28.1%, respectively, higher than the existing process due to increased capital and operating costs. Therefore, a trade-off between environmental benefits and cost has to be balanced for technology selection or new integrated technologies have to be developed to achieve environmentally sustainable wastewater treatment economically.
Life cycle assessment, Life cycle cost, Nutrient removal, Phosphorus recovery, functional units, wastewater treatment plants
Rashid, Siti Safirah
f6cb0563-9242-4cab-a678-5ed71de8a0c0
Liu, Yongqiang
75adc6f8-aa83-484e-9e87-6c8442e344fa
Zhang, Chi
75e54093-1e0b-4db2-8cdd-5982b1dfa626
20 December 2020
Rashid, Siti Safirah
f6cb0563-9242-4cab-a678-5ed71de8a0c0
Liu, Yongqiang
75adc6f8-aa83-484e-9e87-6c8442e344fa
Zhang, Chi
75e54093-1e0b-4db2-8cdd-5982b1dfa626
Rashid, Siti Safirah, Liu, Yongqiang and Zhang, Chi
(2020)
Upgrading a large and centralised municipal wastewater treatment plant with sequencing batch reactor technology for integrated nutrient removal and phosphorus recovery: Environmental and economic life cycle performance.
Science of the Total Environment, 749, [141465].
(doi:10.1016/j.scitotenv.2020.141465).
Abstract
Although nutrient removal and recovery from municipal wastewater are desirable to protect phosphorus resource and water-bodies from eutrophication, it is unclear how much environmental and economic benefits and burdens it might cause. This study evaluated the environmental and economic life cycle performance of three different upgraded Processes A, B and C with commercially available technologies for nutrient removal and phosphorus recovery based on an existing Malaysian wastewater treatment plant with a sequencing batch reactor technology and diluted municipal wastewater. It is found that the integration of nutrient removal, phosphorus recovery and electricity generation in all upgraded processes reduced eutrophication potential by 62–76%, and global warming potential by 7–22%, which, however, were gained at the cost of increases in human toxicity, acidification, abiotic depletion (fossil fuel) and freshwater ecotoxicity potentials by an average of 23%. New technologies for nutrient removal and phosphorus recovery are thus needed to achieve holistic rather than some environmental benefits at the expense of others. In addition, the study on two different functional units (FU), i.e. per m3 treated wastewater and per kg struvite recovered, shows that FU affected environmental assessment results, but the upgraded Process C had the least overall environmental burden with either of FUs, suggesting the necessity to use different functional units when comparing and selecting different technologies with two functions such as wastewater treatment and struvite production to confirm the best process configuration. The total life cycle costs of Processes A, B and C were 10.7%, 29.8% and 28.1%, respectively, higher than the existing process due to increased capital and operating costs. Therefore, a trade-off between environmental benefits and cost has to be balanced for technology selection or new integrated technologies have to be developed to achieve environmentally sustainable wastewater treatment economically.
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More information
Accepted/In Press date: 1 August 2020
e-pub ahead of print date: 5 August 2020
Published date: 20 December 2020
Additional Information:
Funding Information:
The authors thank the Indah Water Konsortium Sdn Bhd (IWK), Malaysia for data provided for this study. The authors also thank the Ministry of Higher Education Malaysia and MARA University of Technology for the scholarship provided to Siti Safirah Rashid for her PhD study at the University of Southampton, UK.
Publisher Copyright:
© 2020 Elsevier B.V.
Keywords:
Life cycle assessment, Life cycle cost, Nutrient removal, Phosphorus recovery, functional units, wastewater treatment plants
Identifiers
Local EPrints ID: 443394
URI: http://eprints.soton.ac.uk/id/eprint/443394
ISSN: 0048-9697
PURE UUID: a32e0a83-2a87-4265-a3f3-b7d15908923b
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Date deposited: 24 Aug 2020 16:32
Last modified: 17 Mar 2024 05:49
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Author:
Chi Zhang
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