Ammonia recovery from chicken manure digestate using polydimethylsiloxane membrane contactor

• Published in: Journal of cleaner production 2018-08, Vol.191, p.99-104
• Main Authors: Sürmeli, Recep Önder, Bayrakdar, Alper, Çalli, Bariş
• Format: Article
• Language: English
• Subjects: Ammonia removal flux; Free ammonia; Gas diffusion; Non-porous; Sweep gas
• ISSN: 0959-6526; 1879-1786
• DOI: 10.1016/j.jclepro.2018.04.138

The ammonia removal and recovery performance of a non-porous tubular PDMS membrane was evaluated in this study by immersing it into chicken manure (CM) digestate and operating it in sweep gas mode at different air flowrates, pH values and total ammonium nitrogen (TAN) concentrations. The TAN removal flux achieved as 1.33 ± 0.10 g/m2/day was comparable to the values obtained with porous membranes used in ammonia recovery from anaerobic digestate. The relative proportion of ammonium and free ammonia, which depends on pH, temperature and TAN concentration of digestate, was found to be more effective than the sweep gas flow rate on ammonia recovery. In this study, it was shown for the first time that the low cost non-porous tubular PDMS membrane contactor is a promising technology for recovery of ammonia from nitrogen rich wastes such as CM digestate. •PDMS membrane contactor was used to recover ammonia from anaerobically digested CM.•The TAN removal fluxes obtained in the range of 1.22 and 1.48 g/m2 day.•The dominant force for ammonia recovery was the diffusion of NH3 and CO2 through the membrane.•The tubular PDMS membrane was demonstrated for the first time for sweep gas ammonia removal from digestate.