Aging infrastructure,
increasing environmental regulations, and
receiving water environment issues stem the need for advanced wastewater
treatment processes across the world. Advanced wastewater treatment
systems treat wastewater beyond organic carbon removal and aim to
remove nutrients and recover valuable products. While the removal
of major nutrients (carbon, nitrogen, and phosphorus) is essential
for environmental protection, this can only be achieved through energy-,
chemical-, and cost-intensive processes in the industry today, which
is an unsustainable trend, considering the global population growth
and rapid urbanization. Two major routes for developing more sustainable
and circular-economy-based wastewater treatment systems would be to
(a) innovate and integrate energy- and resource-efficient anaerobic
wastewater treatment systems and (b) enhance carbon capture to be
diverted to energy recovery schemes. This Mini-Review provides a critical
evaluation and perspective of two potential process routes that enable
this transition. These process routes include a bioelectrochemical
energy recovery scheme and codigestion of organic sludge for biogas
generation in anaerobic digesters. From the analysis, it is imperative
that integrating both concepts may even result in more energy- and
resource-efficient wastewater treatment systems.