Estimation of Biodegradability of CIRA/UNAN-Managua Wastewater Effluent according to ISO 10707 and OECD 301D

Abstract

The study to estimate the biodegradability of wastewater from CIRA/UNAN-Managua was carried out by implementing the ISO 10707 method and OECD 301D Guide Line, essays are known as last easy biodegradability or closed bottle test; for this, it was necessary to develop a liquid inoculum, from an aliquot from the effluent of the secondary settlers of a treatment system of biological origin in an aerated reactor of complete mixture; these microorganisms allowed biodegrading the organic matter of the wastewater. The research included an in situ inspection for the recognition of the ideal point where the samples were taken, as well as the measurement of the flow rate; in turn, the physical-chemical characterization of the effluent was carried out, comparing the results with what is established in the Regulation: Dispositions for the Discharge of Wastewater No. 21-2017 that specifies its Article 22. The estimate of the percentage of biodegradability was 94.78%, obtaining from this result that the effluent is readily biodegradable; parallel to this the analysis of the parameters according to the maximum permissible ranges to characterize provided acceptable values of the wastewater concerning the Regulation.