Nitrificacion heterótrofa en el tratamiento de efluentes lacteos mediante SBR granular aeróbico

BUCCI P. ; COPPOTELLI B.; STAREVICH V, ; MORELLI I.; ZARITZKY N ; CARAVELLI A.

Buenos Aires

Congreso; XXXVII CONGRESO INTERAMERICANO VIRTUAL DE INGENIERÍA SANITARIA Y AMBIENTAL.; 2021

AIDIS

The dairy industry generates large volume of wastewater, with cheese whey being one of the main components. Aerobic processes allow achieving an excellent effluent quality in terms of COD, BOD and nutrient removal from the use of sequential batch reactors (SBRs). In the present study, cheese whey wastewater (model effluent from the dairy industry) was supplemented with ammonia nitrogen to obtain necessary COD: NTK ratios to carry out the aerobic biological treatment. Three conditions were used in order to evaluate the effects of organic load and micronutrients on the process of biological elimination of carbon and nitrogen, by means of aerobic granular biomass produced in the reactors. The first two conditions (SMCM and MCM) were operated with the same organic load, with the difference that MCM was supplemented with micronutrients. The third condition (SMCB) had half the organic load of the two reactors previously described and it did not contain micronutrients like SMCM. The microbial community was analyzed by next generation sequencing technology (NGS). The MCM and SMCB conditions showed successful and similar nitrifying activity, mainly attributed to nitrifying heterotrophs. Bacteria belonging to the genera Flavobacterium (SMCB) and Diaphorobacter (MCM) and the order Planctomycetales were the main candidates responsible for the heterotrophic nitrification process. Nitrifying activity is attributed to the heterotrophic nitrification-aerobic denitrification (HNAD) process as responsible for the observed removal efficiencies