Pathways to a net-zero-carbon water sector through energy-extracting wastewater technologies

Abstract

The energy-consuming and carbon-intensive wastewater treatment plants could become significant energy producers and recycled organic and metallic material generators, thereby contributing to broad sustainable development goals, the circular economy, and the water-energy-sanitation-food-carbon nexus. This review provides an overview of the waste(water)-based energy-extracting technologies, their engineering performance, techno-economic feasibility, and environmental benefits. Here, we propose four crucial strategies to achieve net-zero carbon along with energy sufficiency in the water sector, including (1) improvement in process energy efficiency; (2) maximizing on-site renewable capacities and biogas upgrading; (3) harvesting energy from treated effluent; (4) a new paradigm for decentralized water-energy supply units.

Energy-Water-Food-Environment Nexus and Circular Economy: A Systematic Review

“…The carbon-intensive and energy-intensive wastewater treatment plans might turn into substantial energy manufacturers and recycled metallic and organic substance producers, thus contributing to the circular economy, wide-ranging sustainable development goals, and the energy-water-food-sanitation-carbon nexus [53]. Rani et.al [53] carried out investigations into waste(water)-based energy-extracting innovations, including their engineering performance, environmental benefits, and techno-economic feasibility.…”

“…The carbon-intensive and energy-intensive wastewater treatment plans might turn into substantial energy manufacturers and recycled metallic and organic substance producers, thus contributing to the circular economy, wide-ranging sustainable development goals, and the energy-water-food-sanitation-carbon nexus [53]. Rani et.al [53] carried out investigations into waste(water)-based energy-extracting innovations, including their engineering performance, environmental benefits, and techno-economic feasibility. The study proposed four critical strategies for achieving energy sufficiency and net-zero carbon in the water sector, including (a) upgrading the development of energy efficiency; (b) energy harvesting from treated sewage; (c) optimizing on-site renewable capacity and improving biogas; (d) an innovative approach to decentralized energy-water supply elements.…”

Current trends and future directions of global research on wastewater to energy: a bibliometric analysis and review

“…Encouraging innovation can lead to more cost-effective and environmentally friendly solutions. One example of research innovation is fuel cells which have gained popularity for generating electricity (Rani et al 2022 ). The application of modern treatment techniques like microbial fuel cells (Kunwar et al 2023 ) and microbial electrolysis cells (Deng et al 2023 ) can enable the conversion of wastewater’s chemical energy into electricity without external energy input, leading to significant energy savings and potential energy recovery.…”

Light-Augmented Multi-ion Interaction in MXene Membrane for Simultaneous Water Treatment and Osmotic Power Generation

“…13,14 Harvesting this energy would significantly reduce the net energy consumption for wastewater treatment or even producing net energy and thus economic profit. 15 However, such harvesting is also highly challenging. On one hand, high power density requires a material with high ionic (e.g., Na + ) flux.…”

“…Yet, they were almost exclusively designed for the mixing of seawater and fresh water, neglecting the fact that many other water sources exist. For example, industrial wastewater is constantly discharged into natural water systems, releasing osmotic energy. , Harvesting this energy would significantly reduce the net energy consumption for wastewater treatment or even producing net energy and thus economic profit . However, such harvesting is also highly challenging.…”