Rao, U., Department of Civil and Environmental Engineering, University of California, Los Angeles, CA, United States; Hatch, L.E., Department of Chemical and Environmental Engineering and College of Engineering – Center for Environmental Research and Technology, University of California, Riverside, CA, United States; Tester, J.W., School of Chemical and Biochemical Engineering, Cornell University, Ithaca, NY, United States; Walker, S.L., Department of Chemical and Environmental Engineering and College of Engineering – Center for Environmental Research and Technology, University of California, Riverside, CA, United States; Barsanti, K.C., Department of Chemical and Environmental Engineering and College of Engineering – Center for Environmental Research and Technology, University of California, Riverside, CA, United States; Jassby, D., Department of Civil and Environmental Engineering, University of California, Los Angeles, CA, United States

Increased demand for water, energy and food requires new ways to produce fertilizers, fuels and reusable water. Recovery of resources from wastes could lead to an additional source of energy and nutrients, and also reduce the waste to be disposed. In this work, we used hydrothermal liquefaction to produce a biocrude oil product, followed by membrane distillation of the aqueous effluents to concentrate a nutrient-rich stream that can be used as fertilizer. The motivation for this work is that residual heat from the hydrothermal liquefaction process could be utilized to drive the membrane distillation process, which would improve the efficiency and reduce the cost of the distillation process. The membrane distillation system was demonstrated to be able to recover 75% of the water. The membrane distillation retentate had very high ammonium and phosphate concentrations, making it suitable as a fertilizer. Membrane permeate contained high concentrations of volatile organics. © 2018 Elsevier Ltd