Advanced Water Management Centre

AWMC Seminar Program: Andrew Ward & Navid Moheimani

Dr. Andrew Ward (Post-doctoral Research fellow, AWMC), and an guest speaker Dr. Navid Moheimani (Director of Murdoch University Algae R&D Centre) will present for the AWMC seminar.

PILOT SCALE ELECTRODIALYSIS FOR NUTRIENT RECOVERY (Andrew)

Abstract: Nutrient recovery via an electrodialysis (ED) pilot process was quantified at QUU’s luggage point sewage treatment plant. A concentrated fertiliser product (NH4-N 7069± 317 mg/L and K 2486± 40 mg/L) could be achieved by concentrating nutrient ions from the centrate wastewater feed stream via the ED process. The achievable total NH4-N concentration measured experimentally was 7g N/L. Power consumption utilised by the pilot scale ED cell to transfer 1 kg NH4-N was 4.9 ± 1.5 kWh/kg N averaged across three replicate trials. The reported energy consumption is below previous ED results, and below competing technologies for NH4-N removal and production indicating the importance of pilot testing. The flux densities and initial cell resistance voltage returned to similar ranges for all subsequent replicate treatments indicating operational sustainability at treatment durations of several days. This study demonstrates that ED is an economically promising technology for the recovery of nutrients from wastewater.

Algal culture to treat anaerobic digestion piggery effluent (ADPE) (Navid)

Abstract: Environmental consequences of high productivity piggeries are significant and can result in negative environmental impacts, hence bioremediation techniques (in particular using algae) are therefore of great interest. The overwhelming interest in the use of microalgae and macroalgae to handle associated nutrient surge from anaerobic digestion technologies for the treatment of wastewater, is driven by the need for efficient nutrient recovery, greenhouse gas mitigation, wastewater treatment and biomass reuse. In a series of studies, we tested the feasibility of growth and ammonium nitrogen removal rate of microalgae and macroaglae cultures for treating sand-filtered, undiluted anaerobic digestion piggery effluent (ADPE) under Perth, Western Australia outdoor climatic conditions. Microalgae were grown using paddle wheel driven raceway ponds and tubular photobioreactros. Macroaglae cultures were maintained as biofilm using a algal turf systems. Initial ammonium nitrogen concentration in the Biocoil and raceway pond was 893.03 ± 17.0 mg NH4+-N L− 1. The microalgal consortium in both cultivation systems was dominated by Chlorella and Scenedesmus. Overall, similar average ammonium nitrogen removal rate in Biocoil (24.6 ± 7.18 mg NH4+-N L− 1 d− 1) and raceway pond (25.9 ± 8.6 mg NH4+-N L− 1 d− 1) was achieved. However, the average volumetric biomass productivity of microalgae grown in the Biocoil (25.03 ± 0.24 mg AFDW L− 1 d− 1) was 2.1 times higher than in raceway pond. This microalgal consortium could be maintained in semi-continuous culture for more than three months without changes in the algal composition. A consortium of two macroalgae, Rhizoclonium sp. and Ulothrix sp. was isolated and could efficiently grow in the ADPE. Maximum ammonium removal rate (30.6 ± 6.50 mg NH4+-N L−1 d−1) was achieved at ADPE concentration equivalent to 248 mgNH4+-N L−1. Mean biomass productivity of 31.1 ± 1.14 g ash-free dry weight (AFDW) m−2 d−1 was achieved.

Results of our studies indicated that microalgae consortium is suitable for simultaneous nutrient removal and biomass production from undiluted anaerobic digestion piggery effluent. We also found the potential of use macroalgal consortium for treating diluted ADPE. Produced algal biomass can be used as a source of animal feed or biomethane production.

Bio: Navid is a senior algae technical specialist and has 16 years of experience as an applied phycologist and being involved in biofuel production from microalgae. He is also a director of Murdoch University Algae R&D Centre. His profile, qualifications and publications can be viewed at http://profiles.murdoch.edu.au/myprofile/navid-moheimani/

Event Details
Date & Time: 
Friday, 08 September 2017
9am - 10am
Venue: AIBN Building 75, Level 1 Seminar Room

Event Contact: awmcseminars@awmc.uq.edu.au