About this Research Topic
Wastewater process development has gone through at least three major technology generations; centralized collection and disease control (19th century); organics removal (early 20th century), and biological nutrient removal (late 20th century). It is about to enter its fourth generation, which is change to technology which instead of wastefully dissipating or destroying the valuable resources in wastewater, instead recovers energy, organics, and other resources as valuable byproducts. This is being driven not only by a need for reduced cost and resource, particularly energy consumption, but is also motivated by worldwide depletion of non-renewable macronutrients such as phosphorous, and the need to reduce anthropogenic effects on terrestrial nitrogen cycles. A large part of the world nutrient market (50-100% depending on the nutrient) can be recovered from waste streams, with domestic wastewater being a key developmental platform. While many new technologies are contributing to the challenge of resource recovery from wastewater, biological methods offer the strongest promise to efficiently recover valuable resources from dilute streams. Examples include fast growing heterotrophic, chemotrophic, phototrophic, and photosynthetic bacteria, algae, and terrestrial plants for organics recovery, and the use of highly specialized metal reducing and oxidizing organisms for metal recovery. Adsorbent organisms can be used to recover complex organics, while biopolymers such as polyhydroxyalkanoates and alginates can be generated by accumulative bacteria.
This research topic will focus broadly on biological methods to recover resources from domestic and industrial wastewaters and industrial wastes. The next generation of domestic wastewater treatment plants is approaching energy neutrality and complete recovery of nutrients, particularly N and P. But there are increasing drivers to recover valuable products from wastes and wastewaters of different nature, like those coming from the industrial manufacturing and mining extraction. These compounds are characterized by their high stability and almost non-biodegradability. Some resources that are capable of being recovered by biological technologies includes heavy, precious or radioactive metals, and emerging pollutants like pharmacs, enzymes, hormones, fertilizers and bioplastics, among others. Although some efforts have been dedicated to the recovery of these valuable resources, there is still a need for improving the biological options to reclaim and reuse these substances. This research topic is generally structured in the five major areas of (a) recovery of energy, focusing on sustainable production of energy from wastes (b) biomanufacturing from wastes, focusing on recovery of organics and production of bio-products (c) recovery of macro-elements, including fertilizers, (d) recovery of low concentration and trace elements and (e) integration into wastewater based general recovery systems, including integrated resource recovery plants that may consider all four classes of technology. We will focus the call on even balancing between the five key areas above, with a focus on energy, biomanufacturing, and nutrients, but also integrate the issue through two broad review papers that will (a) assess the relative merit of commodity resource recovery vs biomanufacturing, and identify route for resource recovery to contribute to overall sustainability of society, and (b) identify how resource recovery links into next generation and sustainable agriculture and manufacturing.
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