The development of organic devices based on conducting polymers for biofilm detection requires the combination of superior electrical response and high surface area for biofilm incorporation. Polypyrrole is a potential candidate for application in biofilm detection and control due to its characteristic superior electrical response and strong interaction with bacteria, which enables the use of the bioelectric effect in resulting devices. In this study, chemically synthesized polypyrrole was applied as a support for biofilm growth of S. aureus. Modifications in the electrical response of the polymeric template were explored to identify general mechanisms established during the deposition of the biofilm.

Este trabalho teve por objetivo avaliar o período de partida de um reator anaeróbio horizontal de leito fixo (RAHLF), seguido de um reator anaeróbio de manta de lodo (UASB), para o tratamento de águas residuárias de abatedouro. O RAHLF, preenchido com anéis de bambu, teve 1,2 m de comprimento, 0,10 m de diâmetro e volume útil de 7,5 L. O UASB teve volume útil de 15 L. O RAHLF e o UASB operaram com carga orgânica volumétrica e tempo de detenção hidráulica médios de 8,46 e 3,77 kg m-3 d-1 de DQO e 0,53 e 0,98 dias, respectivamente. Durante 150 dias de monitoramento do sistema, verificaram-se pH de 6,8, valores relativamente elevados de alcalinidade bicarbonato (> 1.000 mg L-1) e reduzidos valores de ácidos voláteis totais (70 a 150 mg L-1), o que proporcionou eficiências médias de remoção de DQO total e sólidos suspensos da ordem de 31 e 23% no RAHLF e de 79 e 63% no UASB. Pode-se concluir que a geração de alcalinidade bicarbonato e consumo de ácidos voláteis totais e consequente manutenção do pH durante o estudo indicaram operação estável dos reatores. A remoção de DQO nos reatores foi satisfatória, principalmente quando se considera que a avaliação foi realizada em período de adaptação dos microrganismos ao efluente e também à elevada carga orgânica aplicada durante este período.

This study aimed to evaluate the start-up of a horizontal anaerobic fixed bed reactor (HAFBR) followed by an upflow anaerobic sludge blanket (UASB) for the slaughterhouse wastewater treatment. HAFBR was filled with bamboo rings and had 1.2 m in length, 0.10 m in diameter and volume of 7.5 L. The UASB had the volume of 15 L. The HAFBR and UASB operated at organic loading rate and hydraulic retention time average of 8.46 and 3.77 kg m-3 d-1 of COD and 0.53 and 0.98 days, respectively. During 150 days of monitoring system it was found pH 6.8, relatively high values of bicarbonate alkalinity (> 1000 mg L-1) and reduced values of volatile acids (70 to 150 mg L-1), which afforded average removal efficiencies of COD total and total suspended solids of the order of 31 and 23% in HAFBR and 79% and 63% in UASB. It can be concluded that the generation and consumption of bicarbonate alkalinity and total volatile acids, thereby maintaining the pH during the study indicated stable operation of the reactors. The COD removal in the reactors was satisfactory especially when it considers that the assessment was conducted in a period of adaptation of organisms to the effluent and also the high organic load applied during this period.