Biodegradation Testing of Bitumen

Abstract

AbstractAn estimate of the rate of biodegradation of bituminous material is necessary to predict the long-term stability of low- and intermediate- level waste solidified using bitumen. Data from a series of scoping experiments have been analyzed to determine the rate of degradation of blown bitumen samples under a variety of conditions. Among the variables investigated were the effect of soil type, moisture, sample surface area and microbial strain. The rate of degradation was measured by monitoring metabolic CO2release. Using this data it was found that, for degradation in soil, a mean rate of 5.5 × 10−4 cm/yr represented all data to within a factor of about two. This mean rate is nearly that for distilled bitumen samples measured by other workers.