EFFECTS OF WOOD ASH IN REMEDIATION OF CRUDE OIL POLLUTED SOILS WITH SOME HEAVY METALS (Cd AND As)

ABSTRACT

This experiment was carried out to observe the effectiveness of wood ash in the remediation of crude oil polluted soils. The experiment was carried out in the Soil Science screen house, Faculty of Agriculture, University of Benin, Benin City, Edo State. The soil sample was generally polluted with crude oil and 3kg polluted soils was filled in poly bags. It was allowed to equilibrate for two weeks, after which 3kg of wood ash was added to the soil to remediate it. The soil samples were watered with 100ml of water per 3kg/weekly for four weeks after introduction of wood ash in the screen house. The soil samples were later collected for laboratory analysis, for soil micronutrient and heavy metals using standard laboratory analysis. At 0kg the total hydrocarbon was 231.93mg/kg, at 2kg it was 77.67mg/kg with a mean of 149.49mg/kg. While the heavy metals mineralized (Cd having a mean of 0.17mg/kg and As 0.13mg/kg), wood ash increased the soil nutrient, (soil pH at 0kg was 5.67g/kg and at 2kg it was 7.81g/kg, available Phosphorus at 0kg was 10.94mg/kg and at 2kg it was 21.61mg/kg, total Nitrogen was 0.98g/kg and at 2.59g/kg and total organic carbon at 0kg was 49.50g/kg and at 2kg it was 88.02g/kg.