caa a22 4500 463195280 CHVBK 20180406164921.0 cr unu---uuuuu 170326e20070601xx s 000 0 eng 10.1007/s10669-007-9005-z doi (NATIONALLICENCE)springer-10.1007/s10669-007-9005-z Nitrogen recovery in an integrated system for wastewater treatment and tilapia production [Elektronische Daten] [Saber El-Shafai, Fatma El-Gohary, Fayza Naser, P. van der Steen, Huub Gijzen] An integrated system, consisting of Up-flow Anaerobic Sludge Blanket (UASB)-duckweed-tilapia ponds was used for recovery of sewage nutrients and water recycling. A UASB reactor with 40 liter working volume was used as pre-treatment unit followed by a series of three duckweed ponds for nitrogen recovery. The treated effluent and duckweed biomass was used to feed fishponds stocked with Nile tilapia (Oreochromis niloticus). The UASB reactor was fed with raw, domestic sewage at 6 h hydraulic retention time. The three duckweed ponds were stocked with Lemna gibba and fed with UASB effluent at 15 days hydraulic retention time. Nitrogen recovery from UASB effluent via duckweed biomass represented 81% of total nitrogen removal and 46.5% from the total nitrogen input to the system. In subsequent fishponds the nitrogen recovery from duckweed as fish feed was in the range of 13.4-20%. This nitrogen in fish biomass represented 10.6-11.5 g N from the total nitrogen in the raw sewage fed to the UASB reactor. The growth performance of tilapia (Oreochromis niloticus) showed specific growth rates (SGR) in the range of 0.53-0.97. The range of feed conversion ratio (FCR) and protein efficiency ratio (PER) were 1.2-2.2 and 2.1-2.28, respectively. The results of the experiments showed total fish yield and net fish yield in the range of 17-22.8 ton/ha/y and 11.8-15.7 ton/ha/y respectively. In conclusion UASB-duckweed-tilapia ponds provide marketable by-products in the form of duckweed and fish protein, which represent a cost recovery for sewage treatment. Springer Science+Business Media, LLC, 2007 Domestic wastewater nationallicence Nutrients recovery nationallicence UASB-duckweed ponds nationallicence Tilapia aquaculture nationallicence Treatment nationallicence El-Shafai Saber Water Pollution Control Department, National Research Centre, El-Tahrir Street, Dokki, Egypt aut El-Gohary Fatma Water Pollution Control Department, National Research Centre, El-Tahrir Street, Dokki, Egypt aut Naser Fayza Water Pollution Control Department, National Research Centre, El-Tahrir Street, Dokki, Egypt aut van der Steen P. Environmental Resources Department, UNESCO-IHE Institute for Water Education, 2601 DA Delft, P.O. Box 2015, Delft, The Netherlands aut Gijzen Huub Environmental Resources Department, UNESCO-IHE Institute for Water Education, 2601 DA Delft, P.O. Box 2015, Delft, The Netherlands aut The Environmentalist Kluwer Academic Publishers-Plenum Publishers; http://www.springer-ny.com 27/2(2007-06-01), 287-302 0251-1088 27:2<287 2007 27 10669 https://doi.org/10.1007/s10669-007-9005-z text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s10669-007-9005-z text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- El-Shafai Saber Water Pollution Control Department, National Research Centre, El-Tahrir Street, Dokki, Egypt aut NATIONALLICENCE 700 1- El-Gohary Fatma Water Pollution Control Department, National Research Centre, El-Tahrir Street, Dokki, Egypt aut NATIONALLICENCE 700 1- Naser Fayza Water Pollution Control Department, National Research Centre, El-Tahrir Street, Dokki, Egypt aut NATIONALLICENCE 700 1- van der Steen P. Environmental Resources Department, UNESCO-IHE Institute for Water Education, 2601 DA Delft, P.O. Box 2015, Delft, The Netherlands aut NATIONALLICENCE 700 1- Gijzen Huub Environmental Resources Department, UNESCO-IHE Institute for Water Education, 2601 DA Delft, P.O. Box 2015, Delft, The Netherlands aut NATIONALLICENCE 773 0- The Environmentalist Kluwer Academic Publishers-Plenum Publishers; http://www.springer-ny.com 27/2(2007-06-01), 287-302 0251-1088 27:2<287 2007 27 10669 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer