Optimization of oil sludge remediation by Lysinibacillus sphaericus using Eisenia fetida

"Oil sludge is a highly contaminant and persistent residue produced during crude oil extraction, transportation and refinement. Biodegradation has been proven to be one of the most efficient, and cost effective technics to remediate this kind of sludge, several studies carried out at the Center of Microbiological Research (CIMIC) from the Universidad de los Andes resulted in the actual bioaugmentation of Lysinibacillus sphaericus to perform oil sludge remediation for Colombian petroleum exploration and production companies. Earthworms can also be used to carry out this process; several studies have shown that the addition of Eisenia fetida to oil sludge results in hydrocarbon degradation and enhanced nutrient cycling, nevertheless these worms tolerate much lower TPH concentrations than bacteria so its application should be carried out as a secondary treatment to improve bacterial activity in the last phases of remediation. Both of these species have been proposed to be capable of increasing soil ammonium and nitrate concentrations, this factor could be crucial in oil remediation processes because of bacterial inhibition due to high C:N ratios. Experiments were undertaken to determine the viability and benefits of a mixture between L. spahericus and E. fetida for oil sludge remediation, oil sludge was also treated with each of the species separately and with none as control, another control was carried out with E. fetida and uncontaminated soil resulting in three treatments and two controls. The presence of E. fetida significantly increased ammonium concentrations (p-value = 0.0218) and total UFC count p-value = 0.02848), however oil sludge with worms and L. sphaericus reached lower concentrations than sludge with worms alone and total UFC count was lower as well, sludge inoculated only with L. sphaericus presented higher ammonium levels than sludge without inoculum but populations reached lower limits after some days. Final DNA and RNA extractions for all treatments..."

• Autores: Acevedo Torrente, Juan Diego
• Tipo de recurso: Trabajo de grado de pregrado
• Fecha de publicación: 2017
• Institución: Universidad de los Andes
• Repositorio: Séneca: repositorio Uniandes
• Idioma: eng
• OAI Identifier: oai:repositorio.uniandes.edu.co:1992/39510
• Acceso en línea: http://hdl.handle.net/1992/39510
• Palabra clave: Hidrocarburos; Lysinibacillus sphaericus; Biodegradación de residuos peligrosos; Biología
• Rights: openAccess
• License: http://creativecommons.org/licenses/by-nc-sa/4.0/