Circular Economy Strategies: From Waste Treatment Plants to Biorefineries

Dear Colleagues,

Increasing environmental problems related to climate change and human socioeconomic development have irretrievably changed the regenerating capacity of the natural resources, thus resulting in a continuous degradation that negatively affects human health and the biodiversity of both aquatic and terrestrial ecosystems. This has led to a dangerous imbalance between demand and increasingly limited resource availability. In order to achieve greater progress as a society without compromising the world we will leave our children, different sectors (academic, scientific, and industrial ones) should face up to the major challenges in the field of sustainability, such as power consumption, depletion of natural resources, high levels of environmental pollution, and the scarcity of high-quality water, among others.

As in the case of water, industries must focus their strategies on the application of the concept of circular economy and zero discharge through the biorefinery/biofactory model. Most industrial sectors are currently working in linear treatment models, locating their wastewater treatment systems at the end of the line, exclusively thinking in reclaiming or regenerating the large volumes of polluted water as waste streams without recovering any compounds. Nonetheless, the concept of circular economy replaces this linear model by optimizing water consumption (giving it a second life as a resource in the industrial plant) and considering wastewater as a source of important resources and high-added value compounds (volatile fat acids or bioactive compounds, among others), which are recovered, retransformed (as bio-based products or food ingredients), recycled, or reused.

Aim:

In the optic of the concept of circular economy, all the process products and by-products should find use with the purpose of minimizing the waste streams and increase product and process value. So, the main aim of this Special Issue is to show the readers the latest approaches and innovations made by researchers at semi-industrial and industrial scale in order to demonstrate both the viability of the circular economy strategies and the significance that biorefineries (“green biorefineries”) will acquire in our near future. Some specific objectives are:

• To confirm the application of the concept of circular economy in different industrial sectors.
• To show the advantages and possibilities of biorefineries in order to obtain chemical building blocks, biomaterials or biofuels from organic waste.
• To demonstrate different successful strategies, configurations or cases existing nowadays in real industrial sectors, as an ever-changing, evolving and adaptable concept.

Scope:

The concept of circular economy can cover a broad scope, but this Special Issue is focused on industrial applications of such strategies from strategic waste management (e.g. minimization and optimization of water use or zero-discharge) to the concept of biorefinery (where bio-based compounds can be achieved and/or developed), passing through potential reuse applications and recovering some high-added value compounds which are valuable for the same company or for other industries.

The proposed Special Issue welcomes papers focused on the latest approaches and innovations related to the concept of circular economy and zero discharge, specifically conceived for the non-academic and industrial sectors. The papers should show originality and an important degree of innovation and scientific soundness in order to provide a significant contribution to the Sustainability journal.

Dr. Jorge Ivars
Guest Editor

Manuscript Submission Information

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• biorefinery
• bio-based products
• bioactive compounds
• circular economy
• nutrients recovery
• water savings
• sustainability