Employment of Aspergillus niger AN 400 in batch reactors to remove pesticide aqueous matrix

<p></p><p>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.</p><p></p

BTEX removal by fungi in continuous flow aerobic reactor

<p></p><p>ABSTRACT The removal of benzene, toluene, ethylbenzene and xylene (BTEX) compounds by Aspergillus niger AN 400 was studied in a continuous flow reactor which was operated at hydraulic retention time (HRT) of 12 hours evaluate the efficiency of the system in the bioremediation of water polluted with gasoline in the presence (Step 1) and absence (Step 2) of 0.5 g.L-1 glucose. In the first step it was also studied the influence of the addition of nutrients in the influent on the efficiency of the process. The addition of nutrients was beneficial to the process and, with the removal of glucose, the efficiency was maintained due to the use of ethanol - which is a Brazilian gasoline constituent (25%) - and was used as co-substrate. Both ethanol and glucose are more easily assimilated carbon and energy sources for fungi and were used as co-substrate in the degradation of BTEX. Thus, in Step 2, when only ethanol was in the biomedia, averages percentage of 88% for benzene, 90% in toluene, 90% ethylbenzene and 91% for meta, para and ortho-xylene (m, p and o-xylene) were reached, with the formation of phenolic by-products in between. The fungal population in the middle prevailed throughout the operation of the reactor.</p><p></p