This study identifies total petroleum hydrocarbons (TPH) and traces of heavy metals such as zinc, lead, cadmium, nickel, and copper in crude oil-contaminated soil. It also focuses on the use of poultry manure and sorghum husk in the bioremediation of the contaminated soil. Crude oil-contaminated soil sample was divided into five parts (A: untreated, B: poultry manure, C and D: poultry manure and sorghum husk in ratios 1:1 and 3:1, respectively, and E: sorghum husk). The heavy metals concentrations and TPH content were assessed initially in the untreated soil sample and later on the 5th, 10th, 15th, 20th, 25th, and 30th days after adding the stimulants. Gas chromatography-mass spectroscopy (GC-MS), atomic absorption spectrometer (AAS), pH and conductivity meters were used for TPH, heavy metals, pH and electrical conductivity analyses, respectively. The results showed soil sample C to have highest TPH reduction, while the soil sample E exhibited 96.1% reduction in nickel, 97.5% reduction in zinc, 100% reduction in lead, and 99.3% reduction in copper. The pH of the soil ranged from 7.13 to 7.92 (within the range 6.5–8 suitable for microbial growth). The electrical conductivity for soil samples B–E increased and also in the acceptable range of 130–2320 μS/cm.
Part of the book: Advances in Bioremediation and Phytoremediation