Technological suitability and improvement for shaping environmental performance: A life cycle perspective on Fenton-based wastewater treatment processes

Abstract

Water resource management and wastewater treatment are designed to ensure a safe and clean water resource in the pursuit of sustainable development goals. Chemical-based wastewater treatment processes typically involve significant consumption of resources, by means of chemical or material uses, which potentially lead to significant environmental impacts. This study intends to gain a comprehensive understanding of the environmental impacts associated with two Fenton-based wastewater treatment processes, namely, fluidized-bed reactor (FBR-Fenton) and conventional Fenton (C-Fenton) methods, for four industrial wastewater tests (organic wastewater from pulp mill, pharmaceutical, oil-containing, and polyethylene terephthalate (PET) rinsing), from a technical suitability perspective. The present study adopts ISO 14040 guidelines for life cycle assessment (LCA) and uses the IPCC and ReCiPe methods for environmental impact assessment. The results show that the FBR process has relatively lower environmental impacts than the C-Fenton process according to the IPCC and ReCiPe impact results, partly due to differences in chemical usage and electricity consumption. The results obtained from the IPCC method show that the C-Fenton process had a relatively higher impact on global warming potential than the FBR process, with impacts in the range of 20.5–141.9 kg CO2eq/1 kg COD and 12.0–41.9 kg CO2eq/1 kg COD, respectively, mainly due to variations in the amount of sodium hydroxide or sulfuric acid required to achieve the desired degree of water quality from different raw industrial wastewater sources. Furthermore, the reduction in the use of high-impact chemicals contributes to remarkable environmental benefits for the processes, while process adjustment may not guarantee environmental benefits. This result implies that the environmental performance of Fenton-based processes significantly varies depending on the treatment of raw wastewater characteristics; that is, the environmental advantage of a wastewater treatment technique strongly depends on the determination of a suitable process. This information can be used to support the determination and advancement of future wastewater treatment technologies aimed at improving environmental outcomes.