High rate algal ponds are an important process of biological treatment used either for domestic sewage or food industries effluents and to produce single cell proteins.
The results refer to the efficiency of treatment of wastewaters from the tomato concentrate industry and determination of the chemical composition of “Albazod” (microbial biomass) harvested in a pilot system of high rate algal ponds installed in the Department of Environmental Engineering, Faculty of Sciences and Technology, New University of Lisbon, at Monte da Caparica.
Depending on the detention time and period of the year, the following removal efficiencies were obtained: COD 68.1 – 94.6%; TOD 57.6 – 85.0%; N-NH4+ 89.4 – 96.2%; colour 29.6 – 91.7% and turbidity 37.2 – 92.7%. Albazod separated from the effluent has a high nutritive value for low detention times (crude protein values of 31.50% and 30.75% dry matter for 4 days and 5 days of detention time, respectively). The highest productivity value was 30.82 g of dry matter/m2/day and was obtained for a detention time of 4 days.