Experience of Application of Natural Treatment Systems for Wastewater (NTSW) in Livestock Farms in Canary Islands

Abstract

A real-scale application experience Natural Treatment Systems for Wastewater (NTSW) operating in continues with livestock farms for one year. These systems are based on digesters, subsurface vertical flow constructed wetlands (SVFCW) and facultative ponds. Chemical Oxygen Demand removal efficiency (CODRE) has obtained between 70 and 90%. Likewise, it have been possible to compare the operation of cascade flow digesters (CFD) (<76% CODRE) versus complete mixing digesters (CMD) (<50% CODRE). Facultative ponds (FP) when combined with (SSFCW), removed a higher percentage of CODRE compared with ponds (92%). Correlations of interest have been found between the variables evaluated in each plant. Finally, different elements are alternated in the same system, this system is capable of supporting variations in changes in flow rate and organic load coming from the farm, maintaining an adequate elimination of COD and other parameters of interest.