Coupling wastewater treatment and algal biomass production: Experience in SE Australia

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2 Coupling wastewater treatment and algal biomass production: Experience in SE Australia Howard Fallowfield, Neil Buchanan & Nancy Cromar Health and Environment Group, School of the Environment, Flinders University, Adelaide, South Australia & 1. Fallowfield, H, Buchanan, N, and Cromar, N (2014) Coupling wastewater treatment and algal biomass production: experience in SE Australia. Algae Event 2014, 22 nd European Union Biomass Conference and Exhibition, Hamburg, Germany, June

3 A bit of history Energy and GHG abatement Energy from algal biomass; Liquid transport fuels Oswald, HRAP Glycerol & edible fat production (diatoms) Burlew Report

4 High rate algal ponds

5 High rate algal ponds (HRAP): Characteristics Shallow (30 60 cm) meandering channel design Mixed by simple paddlewheel Mean surface velocity 0.2 m s -1 Maintains solids algal cells in suspension - maximising O 2 production for treatment Homogenous chemical environment Richmond Calif. Shorter retention times for treatment (5 12d) Reduced evaporative loss Less land area required Holister, Calif

6 Why wastewater?

7 Nutrient availability & cost Cordell, D (2009) The story of phosphorus: 8 reasons why we need to rethink the management of phophorus resources in the global food system available at Impact of Rising Natural Gas Prices on U.S. Ammonia Supply, United States Department of Agriculture, WRS0702 (2007)

8 Sustainable Development of Algal Biofuels in the United States (2012), National Research Council of the National Academies Considered Replacement by algae of 5% of U.S. demand for transportation fuels - 39GL algal biofuel Identified sustainability issues Supply of the key nutrients for algal growth nitrogen, phosphorus, and CO 2. required 6-15 X 10 6 TN and 1-2 x 10 6 TP equivalent to % of the TN and % of TP current use in the US. The quantity of water (whether freshwater or saline water) required for algae cultivation 1 L of gasoline equivalent algal biofuel requires ,650 L of freshwater at least 123 GL of water would be needed to produce 39 GL of algal biofuels

9 Sustainable Development of Algal Biofuels in the United States (2012), National Research Council of the National Academies Recommendation: Sustainable development of algal biofuels requires research, development, and demonstration of the following: The use of wastewater for cultivating algae for fuels or the recycling of harvest water, particularly if freshwater algae are used. Sustainable Development of Algal Biofuels in the United States (2012), Committee on the Sustainable Development of Algal Biofuels; Board on Agriculture and Natural Resources, Division on Earth and Life Studies; Board on Energy and Environmental Systems, Division on Engineering and Physical Sciences; National Research Council of the National Academies, pp344. Prepublication Copy available at

10 Simplified process cycle

11 SE Australia : Domestic Wastewaters

12 Kingston on Murray South Australia Kingston on Murray

13 Study site Flinders University 500 km return Kingston on Murray

14 SA: Community wastewater management schemes High rate algal pond (HRAP)

15 Kingston on Murray HRAP: Overview Township Population Effluent treated 12 m 3 /d Climate Irradiance 8.3 MJm -2 (June winter) to 28.1 MJm -2 (January summer) 3.8 C minimum July to 31.8 C maximum in January, HRAP Surface area 200m 2 Operated at m depth THRT 5d Mixing 0.2m/s

16 Kingston on Murray HRAP wastewater treatment performance (n=120) Inlet (pre-treated in septic tanks) % Removal BOD 5 (mg/l) NH 4 -N (mg/l) TN (mg/l) PO 4 -P (mg/l) E.Coli (MPN/100ml) * * log 10 reduction value

17 Albazod & Algal Productivity (g/m 2 /d) mean ±standard deviations & ranges (Buchanan, N, 2014, PhD Thesis, Flinders University) Albazod Productivity (g/m 2 /d) Mean ± sd (Range) Deep-Cold 6.4±5.0 ( ) Shallow-Hot 49.5±33.9 (12-113) Annual ±34.4 All depths ( ) Algal Productivity (g/m 2 /d) Mean ± sd (Range) 3.37± 2.92 ( ) 25.31±17.71 ( ) 20.7±20.6 ( )

18 Net daily biomass energy production 1DO.4.2 Algal biomass production in high rate algal ponds operated in series Using wastewater from a rural community in South Australia, Thursday CV4.56 Carbon : nutrient ratios in two high rate algal ponds operated in series fed Domestic wastewater. Is carbon limiting algal growth. Poster

19 Melbourne Water Victoria Melbourne

20 Wastewater CH 4 & CO 2 Wastewater Wastewater + CO 2

21 Research objectives Determine biomass productivity species proximate composition Determine wastewater treatment potential BOD 5, nutrient removal E.coli removal l Compare performance ± CO 2 addition Provide data for LCA

22 Intensive livestock wastewaters: Pig slurries

23 Experience in wastewater treatment using microalgae - UK Piggery wastewater Northern Ireland Screened pig slurry 1:9 diluted to enable growth THRT 4.4d, depth 0.2m Productivity 18.1 g DM m -2 d -1 West of Scotland Aerobically pre-treated 11m 2, 0.2m, diluted 1:4 Productivity 18.3 g DM m -2 d -1 Ammonia toxicity and light attenuation significant problems

24 Adelaide

25 Co-operative Research Centre for High Integrity Australian Pork (Pork CRC) Reduce GHG emissions from 8kg CO 2 e / kg pork to 1 kg CO 2 e / kg 83% pork producers use ponds to treat wastewater LCA, GHG emissions reduced by: covering anaerobic lagoons; recovering CH 4 Incorporating further algal treatment for: Biomass energy CH 4 High quality reuse water

26 Piggery wastewaters : Australia

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28 Acknowledgements Ken Baxter, Wade Mosse Richard Gayler Jessica Yeung Roger Campbell Graeme Crook