Energy and nutrient recovery from municipal and industrial waste and wastewater-a perspective

Abstract

This publication highlights the latest advancements in the field of energy and nutrient recovery from organics rich municipal and industrial waste and wastewater. Energy and carbon rich waste streams are multifaceted, including municipal solid waste, industrial waste, agricultural by-products and residues, beached or residual seaweed biomass from post-harvest processing, and food waste, and are valuable resources to overcome current limitations with sustainable feedstock supply chains for biorefining approaches. The emphasis will be on the most recent scientific progress in the area, including the development of new and innovative technologies, such as microbial processes and the role of biofilms for the degradation of organic pollutants in wastewater, as well as the production of biofuels and value-added products from organic waste and wastewater streams. The carboxylate platform, which employs microbiomes to produce mixed carboxylic acids through methane-arrested anaerobic digestion, is the focus as a new conversion technology. Nutrient recycling from conventional waste streams such as wastewater and digestate, and the energetic valorization of such streams will also be discussed. The selected technologies significantly contribute to advanced waste and wastewater treatment and support the recovery and utilization of carboxylic acids as the basis to produce many useful and valuable products, including food and feed preservatives, human and animal health supplements, solvents, plasticizers, lubricants, and even biofuels such as sustainable aviation fuel.

One-sentence summary: Multifaceted waste streams as the basis for resource recovery are essential to achieve environmental sustainability in a circular economy, and require the development of next-generation waste treatment technologies leveraging a highly adaptive mixed microbial community approach to produce new biochemicals, biomaterials, and biofuels from carbon-rich organic waste streams.

Keywords: anaerobic digestion; biofilm; carboxylate platform; digestate treatment; mixed microbial community.

Graphical Abstract

Fig. 1.

(a) Overall conversion observed in AM acidogenic fermentation. (b) Metabolic pathways in primary fermentation in AM acidogenic fermentation. (c) Metabolic pathways in secondary fermentation in AM acidogenic fermentation showing chain-elongation (reverse β-oxidation) as described in (De Groof et al., 2019). SCCAs, short-chain carboxylic acids; MCCAs, medium-chain carboxylic acids. Figure 1a (https://BioRender.com/l26u198) and c (https://BioRender.com/q31o230) were created using Biorender.