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Title: Resource recovery from anaerobic digestion effluent by a hybrid algal photosynthesis and ion-exchange process
A hybrid algal photosynthesis and ion exchange (HAPIX) process was developed that uses natural zeolite (chabazite) and wild type algae to treat high ammonium strength wastewater. In the HAPIX process, ammonium ions are temporarily adsorbed from the liquid, which reduces the free ammonia concentration below the inhibitory level for algal growth. The slow release of adsorbed NH4+ subsequently supports the continuous growth of algae. In this study, a HAPIX reactor reduced NH4+-N concentrations in centrate from an anaerobic digester from 1,180 mg/L to below 10 mg/L without dilution. Chabazite doses of 60 g/L produced more biomass, with higher protein and starch contents, than doses of 150 g/L and 250 g/L. Approximately 67-70% of fatty acids in the biomass harvested from HAPIX reactors were unsaturated. A mathematical framework that couples a homogeneous surface diffusion model with a co-limitation algal kinetic growth model reasonably predicted the biomass production and NH4+-N concentrations in the HAPIX reactors. The HAPIX process has the potential to serve a two-fold purpose of high NH4+-N strength wastewater treatment and agricultural or commercial biopolymer production.  more » « less
Award ID(s):
1730586
PAR ID:
10076892
Author(s) / Creator(s):
; ; ;
Date Published:
Journal Name:
IWA Leading Edge Technology Conference on Water and Wastewater Treatment
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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