Closing the Nutrient Loop—The New Approaches to Recovering Biomass Minerals during the Biorefinery Processes

Abstract

The recovery of plant mineral nutrients from the bio-based value chains is essential for a sustainable, circular bioeconomy, wherein resources are (re)used sustainably. The widest used approach is to recover plant nutrients on the last stage of biomass utilization processes—e.g., from ash, wastewater, or anaerobic digestate. The best approach is to recover mineral nutrients from the initial stages of biomass biorefinery, especially during biomass pre-treatments. Our paper aims to evaluate the nutrient recovery solutions from a trans-sectorial perspective, including biomass processing and the agricultural use of recovered nutrients. Several solutions integrated with the biomass pre-treatment stage, such as leaching/bioleaching, recovery from pre-treatment neoteric solvents, ionic liquids (ILs), and deep eutectic solvents (DESs) or integrated with hydrothermal treatments are discussed. Reducing mineral contents on silicon, phosphorus, and nitrogen biomass before the core biorefinery processes improves processability and yield and reduces corrosion and fouling effects. The recovered minerals are used as bio-based fertilizers or as silica-based plant biostimulants, with economic and environmental benefits.

Biomass: A Versatile Resource for Biofuel, Industrial, and Environmental Solution

“…To summarize, the incorporation of biomass into oil spill cleanup efforts ushers in a new age of environmental research, providing novel methods to mitigate the negative consequences of oil spills on marine ecosystems and coastal communities. Researchers and practitioners can advance the field of oil spill response by leveraging the possible benefits of biomass-based sorbents and innovative cleaning approaches, ensuring the health and resilience of our seas and natural ecosystems for future generations [226], [227].…”

Evaluating the Environmental Sustainability of Silica Passivation for Acid Mine Drainage Treatment in Moatize's Coal Industry

“…While the LCA result suggests a low risk of eutrophication from silica passivation, it's important to acknowledge that even though the passivation process itself might not introduce significant nutrients, other factors during the life cycle could contribute. For instance, if fertilizers are used during silica production or if the processing chemicals contain nutrients, these could potentially lead to increased nutrient levels in freshwater bodies (Constantinescu-Aruxandei & Oancea, 2023).…”

Preparation of Ceramic Granules Enriched with Silicon Extracted from Reeds

“…The main issue with the industrial processing of reed biomass is related to its high biosilica content, which increases the risk of silica scale [4]. The pretreatment of reed biomass for biosilica extraction reduces the silica scale risk and represents a solution to close the loop of the biosilica cycle [5].…”

“…One gap in reed biosilica loop closure is the appropriate soil application formulation of the extracted soluble silicon [5]. The solution investigated in this article is the embedment of the silicon species resulting from the concentrated aqueous reed extract in porous ceramic granules that include diatomaceous earth and bentonite from the winemaking industry.…”