Emprego de Aspergillus niger AN 400 em reatores de bancada para remover pesticida de matriz aquosa / Employment of Aspergillus niger AN 400 in batch reactors to remove pesticide aqueous matrix

RESUMO

RESUMO Esta pesquisa propõe utilizar o fungo Aspergillus niger AN 400 no tratamento de matriz aquosa contendo metil paration por meio de reatores em batelada, sendo dividida em duas etapas. Na etapa I, foram montados reatores controle (RCs) contendo apenas metil paration em matriz aquosa; reatores contendo metil paration e suspensão de esporos de fungo (RFs); e reatores contendo metil paration, suspensão de esporos de fungo e etanol (RFEs). A cada tempo de reação (TR), um RC, um RF e um RFE eram colocados fora de operação. Os TRs estudados foram distribuídos em 30 dias. Na etapa II, operou-se um reator com biomassa imobilizada (RBI) alimentado por metil paration e etanol, efetuando-se cinco ciclos cada um com duração de uma semana. Como resultados, na Etapa I, verificou-se que o pH variou de 5 a 8, atingindo remoções finais de 61% (RF) e 89% (RFE) de demanda química de oxigênio (DQO) bruta; 67% (RF) e 52% (RFE) de nitrogênio amoniacal; 34% (RF) e 45% (RFE) de nitrato; 2% (RF) e 15% (RFE) de fósforo total. Na Etapa II, o pH variou de 3 a 8 e as médias de remoção final foram: 94% de DQO filtrada, 88% de DQO bruta, 19% de nitrogênio amoniacal, 96% de nitrato, 12% de fósforo total e metil paration de 95%, com biomassa imobilizada e 73% (95%) com biomassa dispersa. Os resultados mostraram que a utilização do fungo Aspergillus niger AN 400 pode ser uma alternativa no tratamento de água residuária contendo metil paration.

ABSTRACT

ABSTRACT This research proposes the use of the fungus Aspergillus niger AN 400 in treating aqueous matrix containing methyl parathion in batch reactors. The research was divided into two steps. In Step I, were mounted control reactors (RC) containing only methyl parathion in aqueous matrix; reactors with fungus (RF) containing methyl parathion and suspension of fungus spores; and reactors with fungus and ethanol (RFE) containing methyl parathion, the suspension of fungus spores and ethanol. Each reaction time (TR), one RC, one RF and one RFE were put out of operation. The reaction times were studied in 30 days. In Step II, operated a reactor with immobilized biomass (RBI) with methyl parathion and ethanol, making up 5 cycles each lasting one week. As a result, in Step I, it was found that the pH varied from 5 to 8. The final removal of 61% (RF) and 89% (RFE) of COD; 67% (RF) and 52% (RFE) of ammonia nitrogen; 34% (RF) and 45% (RFE) nitrate; 2% (RF) and 15% (RFE) of total phosphorus. In Step II, the pH ranged from 3 to 8 and the average final removal were 94% of filtered COD, 88% gross COD, 19% of ammonia nitrogen, 96% nitrate, 12% of total phosphorus and 95% of methyl parathion with immobilized biomass and 73% with disperse biomass. The results showed that the use of the fungus Aspergillus niger AN 400 can be an alternative for treating wastewater containing methyl parathion.