Bench-top bioreactors development for bioremediation of soil contaminated with B5 diesel

• Main Authors: Francisco Maciel Monticeli, Denise Celeste Godoy de Andrade Rodrigues, Sergio Machado Corrêa
• Format: Article
• Language: English
• Published: Centro Universitário Estadual da Zona Oeste 2018-09-01
• Series: Acta Scientiae et Technicae
• Online Access: http://www.uezo.rj.gov.br/ojs/index.php/ast/article/view/199

Petroleum derivatives are the main  energy sources and a potentially pollution source. The increasing use of automobiles generated a proportional increase in gas stations number. With the introduction of the diesel / biodiesel mixture in the Brazilian energy matrix, resulted in increased bioremediation studies of this contaminated soil. Bioreactors are closed systems for variables and treatment control. In addition, it has the possibility to collect the gases produced during the contaminants degradation and treat it. This study aimed to design bioreactors bench and evaluate remediation ability of different experimental conditions of soil contaminated with diesel B5. The bioreactors were constructed using a bottle, provided with bottom drain, air inlet pipe, crushed stone layer to scattering inlet air, thin nylon screen and silicone for sealing. The air flow injected into the system was controlled by rotameters, with flow injection controlled during continuous time intervals. The soil was artificially contaminated with 5% B5 diesel and the humidity was controlled at 50% of the estimated field capacity (30.5%). The nutrients were added to establish nutritional relation C: N: P for 100: 10: 1 and the microorganism received microbial consortium. The tested treatment were monitored Natural Attenuation (no nutrients); biostimulation (with nutrients); biostimulation with bioaugmentation (with nutrients and consortium) with and without air flow. Considering the results found, it was concluded that the projected bioreactors can be used in soil bioremediation studies. It has been demonstrated that naturally soil decontamination presented low level of remediation, proving the need for soil bioremediation methodologies with greater yield. Asystem was a primary factor to remediation contribution of the contaminated soil. It can be concluded that the system with nutritional adjustment, with bioaumento and with aeration system provided the bioremediation more than 80% during 120 days, being the best bioremediation system.