Removal of benzene from oil refinery wastewater treatment plant exhausted gases with a multi-stage biofiltration pilot plant

Benzene removal from exhausted gases is a tricky issue and is usually carried out by the means of chemical processes. Such systems require reactants, produce waste and are energy demanding. Biological systems can be a cost-effective solution. The paper presents the results obtained in a multi-stage biological system for benzene and other aromatics removal from exhausted gases of a wastewater treatment plant working with oil refinery pavement wastewaters. The system, based on a bioscrubber, two biotrickling filters and one biofilter, obtained removal efficiencies always over the 70%, also giving good results with fluctuating inlet concentrations.