@article{guerdat_losordo_delong_jones_2013, title={An evaluation of solid waste capture from recirculating aquaculture systems using a geotextile bag system with a flocculant-aid}, volume={54}, ISSN={["0144-8609"]}, DOI={10.1016/j.aquaeng.2012.10.001}, abstractNote={Abstract Two separate geotextile bag systems were evaluated as a means for capturing and dewatering bio-solids in the effluent stream from recirculating aquaculture systems (RAS). Each geotextile bag system used a high molecular weight cationic polyacrylamide (PAM) polymer as a flocculant-aid. The two systems were operated under freshwater and brackish water conditions. A complete analysis including water quality and agronomic sludge analysis was conducted at the North Carolina State University Fish Barn – a large-scale, freshwater RAS demonstration and growout facility. An evaluation of water quality and performance of a similar geotextile bag system was also conducted at the Marine Aquaculture Research Center near Marshallberg, North Carolina, USA, under brackish conditions (15 PPT). Results indicated that performance of each of the systems was similar with TSS, COD, TN, and TP removal greater than 95%, 65%, 50%, and 38%, respectively, for both systems. Analysis of the sludge collected in the freshwater system after 70 days in a dewatering, inactive mode, showed a moisture content (MC) of 86%, or 14% dry matter (DM), indicating the system was effective at passively dewatering the bio-solids. Nutrient removal efficiency may be system specific based on the geotextile bag size and influent flow rate. Geotextile bag systems using flocculant-aids are an efficient means for capturing and dewatering waste solids from RAS effluents. Optimized geotextile bag system designs depend on flow rate, feed rate, and solids dewatering time, and fate of the treated effluent. This evaluation will aid in predicting the expected performance and determining the appropriate size of a geotextile bag system. The type of treatment required downstream from the geotextile bag system used for solids capture in a RAS wastewater treatment system will depend on the intended fate of the treated effluent.}, journal={AQUACULTURAL ENGINEERING}, author={Guerdat, Todd C. and Losordo, Thomas M. and DeLong, Dennis P. and Jones, Richard D.}, year={2013}, month={May}, pages={1–8} }
 @article{guerdat_losordo_classen_osborne_delong_2011, title={Evaluating the effects of organic carbon on biological filtration performance in a large scale recirculating aquaculture system}, volume={44}, ISSN={["1873-5614"]}, DOI={10.1016/j.aquaeng.2010.10.002}, abstractNote={Studies evaluating the impact of organic carbon on biological filters at the large scale for aquaculture production are lacking. Understanding the performance characteristics of different biofilters under actual production conditions will be the only means by which recirculating system designers may properly select and size biological filters for commercial production use. Previous studies have determined the impact of organic carbon on biofilter performance at the small lab scale often using artificial waste nutrients in the evaluation. Evaluations under actual production conditions using real wastewater produce vastly different results than previous lab scale studies using artificial nutrients. As such, this study is a preliminary step in evaluating the impact of organic carbon on three different commercially available biological filters at the large scale under actual recirculating aquaculture production conditions. The study was conducted at the North Carolina State University Fish Barn—a commercial scale research and demonstration recirculating aquaculture facility operated by the Biological and Agricultural Engineering department. The study was based on a 60 m3 Tilapia system with average daily feed rates of 45 kg using a 40% protein feed and an average biomass of 6750 kg. The system was dosed with sucrose (C12H22O11) to increase the concentration of biodegradable organic carbon in the system. The effect of elevated organic carbon concentrations on total ammoniacal nitrogen (TAN) removal rates was evaluated and determined based on biofilter media volume. Variability increased substantially in the volumetric TAN removal rate (VTR) for all three filters. VTR for all three filter types was reduced by approximately 50% as compared to normal production conditions. The results demonstrate the importance of controlling the concentration of biologically available organic carbon in a recirculating aquaculture system.}, number={1}, journal={AQUACULTURAL ENGINEERING}, author={Guerdat, Todd C. and Losordo, Thomas M. and Classen, John J. and Osborne, Jason A. and DeLong, Dennis}, year={2011}, month={Jan}, pages={10–18} }
 @article{guerdat_losordo_classen_osborne_delong_2010, title={An evaluation of commercially available biological filters for recirculating aquaculture systems}, volume={42}, ISSN={["0144-8609"]}, DOI={10.1016/j.aquaeng.2009.10.002}, abstractNote={Abstract Three different commercially available biological filters were evaluated in triplicate on a 60 m3 tank-based Tilapia system under commercial warmwater growout conditions. The study was performed at the North Carolina State University Fish Barn—a commercial scale research and demonstration recirculating aquaculture facility operated by the department of Biological and Agricultural Engineering. Total ammoniacal nitrogen (TAN) removal rates were determined for the three types of biofilters for a range of concentrations ranging from 0.13 to 1.20 g TAN m−3. TAN concentrations were varied by feed rates and ammonium chloride additions, and limited by fish feeding response. Maximum feed rates were 65 kg feed d−1 using a 40% protein diet at a maximum biomass of 5500 kg. Average observed TAN removal rates (in g TAN m−3 of unexpanded media d−1 ± standard deviation) for the three filters were 267 ± 123, 586 ± 284, and 667 ± 344 for the moving bed bioreactor, floating bead filter, and fluidized sand filter, respectively. These results are considerably lower than results previously published at the laboratory scale using artificial waste nutrients. This study highlights the need for future biofilter evaluations at the commercial scale using real aquaculture waste nutrients.}, number={1}, journal={AQUACULTURAL ENGINEERING}, author={Guerdat, Todd C. and Losordo, Thomas M. and Classen, John J. and Osborne, Jason A. and DeLong, Dennis P.}, year={2010}, month={Jan}, pages={38–49} }
 @article{delong_losordo_2006, title={A comparison of alternative designs and technologies in recirculating aquaculture}, ISBN={0978094301}, journal={Aquaculture Canada 2004 : ?b proceedings of contributed papers, Canadian Freshwater Aquaculture Symposium, Que?bec City, Que?bec, October 17-24, 2004}, publisher={St. Andrews, N.B. :  Aquaculture Association of Canada}, author={DeLong, D. P. and Losordo, T. M.}, editor={E?. Gilbert, D. Stechey and Struthers, M.Editors}, year={2006} }
 @article{losordo_hobbs_delong_2000, title={The design and operational characteristics of the CP&L/EPRI fish barn: a demonstration of recirculating aquaculture technology}, volume={22}, ISSN={["0144-8609"]}, DOI={10.1016/S0144-8609(00)00029-7}, abstractNote={The Carolina Power & Light Company, in conjunction with the Electric Power Research Institute of Palo Alto, California has developed a commercial fish production demonstration utilizing water reuse technology developed at the North Carolina State University Fish Barn. The fish production system is housed in a 39.6 m long by 9.75 m wide barn structure located on the campus of North Carolina State University in Raleigh, NC. Fish production activities began in the spring of 1998. The facility is designed to produce 45 tonnes of fish annually, with the first crop being tilapia. The project is being operated as a public demonstration of this technology, with biological, engineering and economic data being collected by research and extension personnel at North Carolina State University. This paper outlines the design of the recirculating system technology used to recycle water through the main fish production tanks.}, number={1-2}, journal={AQUACULTURAL ENGINEERING}, author={Losordo, TM and Hobbs, AO and DeLong, DP}, year={2000}, month={May}, pages={3–16} }