Biofertilizer recovery from organic solid wastes via hydrothermal liquefaction. (October 2021)

• Record Type: Journal Article
• Authors: Munasinghe-Arachchige, S.P.; Abeysiriwardana-Arachchige, I.S.A.; Delanka-Pedige, H.M.K.; Nirmalakhandan, N.
• Is Part Of: Bioresource technology. Volume 338(2021)
• Publication Date: 2021-10
• Subjects: Organic solid waste management -- Hydrothermal liquefaction -- Byproducts valorization -- Struvite recovery -- Ammonium sulfate recovery; Biomass -- Periodicals; Biomass energy -- Periodicals; Bioremediation -- Periodicals; Agricultural wastes -- Periodicals; Factory and trade waste -- Periodicals; Organic wastes -- Periodicals; Bioénergie -- Périodiques; Déchets agricoles -- Périodiques; Déchets industriels -- Périodiques; Déchets organiques -- Périodiques; Déchets (Combustible) -- Périodiques; 662.88
• DOI: 10.1016/j.biortech.2021.125497
• Languages: English
• ISSNs: 0960-8524

Abstract

Graphical abstract: Highlights: Developed a process train for recovering biofertilizers from organic solid wastes. Recovered 84% P and 46% N in algal biomass via hydrothermal liquefaction. Demonstrated yields of 8.2 g struvite and 10.7 g ammonium sulfate per 100 g algae. Abstract: Hydrothermal liquefaction (HTL) has emerged as a viable pathway for processing wet organic solid wastes (OSW) to yield biocrude oil which could be upgraded to transportation fuels and specialty chemicals. The HTL process results in two byproducts laden with high levels of carbon, nitrogen, and phosphorous. Recovery of phosphates in the byproducts as struvite and ammoniacal-nitrogen (NH4 -N) as ammonium sulfate is proposed here as a promising pathway to utilize the HTL byproducts. A case study of this pathway using algal biomass as a model OSW yielded 8.2 g struvite/100 g OSW and 10.7 g ammonium sulfate/100 g OSW. Heavy metal levels in both struvite and ammonium sulfate crystals were below EPA regulations for land application. This biofertilizer recovery pathway could render OSW processing by HTL a greener alternative to anaerobic digestion, offering feedstock versatility, substantially smaller footprint, and a higher degree of OSW valorization.