Hydrothermal liquefaction (HTL) is of interest in producing liquid fuels from organic waste, but the process also creates appreciable quantities of aqueous co-product (ACP) containing high concentrations of regulated wastewater pollutants (e.g., organic carbon, nitrogen (N), and phosphorus (P)). Previous literature has not emphasized characterization, management, or possible valorization of ACP wastewaters. This study aims to evaluate one possible approach to ACP management via recovery of valuable scarce materials. Equilibrium modeling was performed to estimate theoretical yields of struvite (MgNH₄PO₄·6H₂O) from ACP samples arising from HTL processing of selected waste feedstocks. Experimental analyses were conducted to evaluate the accuracy of theoretical yield estimates. Adjusted yields were then incorporated into a life-cycle energy modeling framework to compute energy return on investment (EROI) for the struvite precipitation process as part of the overall HTL life-cycle. Observed struvite yields and residual P concentrations were consistent with theoretical modeling results; however, residual N concentrations were lower than model estimates because of the volatilization of ammonia gas. EROI calculations reveal that struvite recovery is a net-energy producing process, but that this benefit offers little to no improvement in EROI performance for the overall HTL life-cycle. In contrast, corresponding economic analysis suggests that struvite precipitation may be economically appealing.

Coastal resilience, risk analysis, disaster recovery, and hazard mitigation are all vital concepts to the functioning of coastal regions. This research aimed to adapt the most recent recovery and resilience functions developed for residential homes by considering measurable factors that are known to influence recovery, including available resources and preparedness. The loss function developed for residential homes damaged by hurricanes was adapted to account for multiple hazards. The resilience model developed through this study investigated resiliency of individual residential homes across several communities. The model was validated using the observed damage from Hurricane Sandy in 2012 in the study region. The results of this study provide improved hurricane loss, recovery, and resilience functions for more accurate use with individual residential structures. Thus, this research provides an essential, innovative contribution to the quantification of infrastructure resilience at the residential level.