Enhancing crude oil degradation in a sandy soil: Effects of addition of poultry manure

Abstract

Natural restoration of crude oil polluted soils takes a long time, hence various soil treatments have been used to hasten the process. This study investigated the effects of the addition of poultry manure alone and in combination with surfactant (Goldcrew or Corexit) and/or alternate carbon substrate (glucose or starch) on crude oil degradation in a sandy soil. With poultry manure alone, optimal crude oil degradation was obtained at a concentration of 4.0% (w/w). At a poultry manure concentration of 1.0% (w/w), addition of either of the surfactants at 0.01% (v/w) did not significantly enhance crude oil degradation (P>0.05), while addition of either of the alternate carbon substrates at 0.5% (w/w) significantly increased the toluene extractable oil content (P<0.05). Enhanced degradation was observed with a combination of poultry manure (4.0%w/w) + Goldcrew (0.01%v/w) + glucose (0.5% w/w). Time course for crude oil degradation in samples which were given optimal treatments that contained poultry manure showed that after sixteen weeks incubation, the highest crude oil degradation of 7.92 ± 0.75% was observed from the sample treated with poultry manure alone at 4 % (w/w).



KEY WORDS: Poultry manure, Surfactants, Alternate carbon substrates, crude oil degradation.

Global Journal of Environmental Sciences Vol.4(1) 2005: 5-10