Concepção e avaliação de sistema de tratamento com reator anaeróbio de mata de lodo (UASB) e lagoa de polimento para águas residuárias de suinocultura

Abstract

This research presents the conception, the development and the evaluation of a system for treatment of swine wastewaters constituted by an slat settler, followed by an upflow anaerobic sludge blanket reactor (UASB reactor), on a real scale, and a post-treatment pond, on ademonstration scale, in operation for 10 months. The system also comprises a tank with chambers in series, to manure storage pipes the of settler. The system was completely made of masonry and reinforced concrete and its pipes were in PVC. The system was implemented inthe Professor Helio Barbosa Experimental Farm swine, situated in the town of Igarapé/MG. The treatment system was monitored by means of samples collected from the influents and effluents from the settler, UASB reactor and post-treatment pond. The following parameters wereanalyzed: temperature, pH, alkalinity, total volatile acids, total solids (TS), volatile solids (TSV), suspended solids (TSS), volatile suspended solids (VSS), biochemical oxigen demand (BOD), chemical oxigen demand (COD), total Kjeldahl nitrogen (NTK), ammonia nitrogen and organicnitrogen, phosphorus, coliforms, according to the methods established by the Standard Methods (APHA AWWA WEF, 1998). The average results of COD and BOD removal were 94,8 and 97,4%, respectively. The average concentrations of COD in the final effluent ranged between240 and 3110 mg L-1, while the average concentrations of BOD varied from 54 to 1300 mg L-1. The overall averages of TSS in the final effluent varied from 30 to 1200 mg L-1. The organic volumetric load (OVL) in the UASB reactor ranged from 1,1 to 17,5 kg COD m-3 d-1. The UASBreactor comes out as a promising alternative for the treatment of swine wastewaters.