Evaluation of the Influence of Soil Density on Retention of Benzene and Light Petroleum Fractions

摘要

The benzene and light petroleum fractions that were spilled during the life of the refinery were notremediated. Density is a physical property that is characteristic of soil and provides information on itsporosity, aeration and infiltration capacity. Density is an important factor in determining the mass ofcontaminant present in the soil. The objective of this study was to evaluate the influence of soil densityon the retention of benzene and light petroleum fractions. The results showed that the influence of soildensity in determining the mass of a specific contaminant, by employing mass balance, is directlyproportional to the density values that were used. When calculating mass with bulk density, theamount is lower than the amount obtained with real density. This observation is based on bulk densitytaking into account in the sample volume, the volume as a whole which includes pore volume. Thevolume of porous space is therefore reduced and accounts for an increase of the mass of contaminantfound at that depth. It was possible to determine the influence of density of the soil in a real case,specifically for a large-size environmental liability, and to obtain suitable information on the mass ofremaining contaminant after applying mass balance. The mass of contaminant that is obtained representsa proportional percentage of the value of the density as it increases, when taking bulk density as areference. This finding is consistent with those that have been published in studies for columns,except this case was a study of an environmental liability instead of being a laboratory study.