Polycyclic aromatic hydrocarbon removal from petroleum sludge cake using thermal treatment with additives

Petroleum sludge is a hazardous waste that contains various organic compounds including polycyclic aromatic hydrocarbons
(PAHs) which have carcinogenic–mutagenic and toxic characteristics. This study focuses on the thermal treatment (indirect heating) of petroleum sludge cake for PAH degradation at 250, 450, and 650 ◦C using Ca(OH)2 + NaHCO3 as an additive. The treatment was conducted in a rotary drum electric heater. All experiments were carried out in triplicate. Concentrations of the 16 priority PAHs in gas (absorbed on Amberlite XAD-4 adsorbent), particulate (on quartz filter) and residue phases were determined using gas chromatography-mass spectrometry (GC-MS). The samples were extracted with acetonitrile by ultra-sonication prior to GC-MS analysis. The use of additive was beneficial and a temperature of 450 ◦C was suitable for PAH degradation. Low levels of PAH emissions, particularly carcinogenic PAH and toxic equivalent concentration (�TEC), were observed in gas, particulate and residue phases after treatment.