The pyrolysis characteristics of petroleum sludge samples collected from crude oil tank and cleaning water reservoir under two slow heating rates(5℃·min~(-1) and 2℃·min~(-1)) were experimentally studied in a fixed bed reactor. Thermogravimetric analysis was carried out for deducing reaction kinetics based on Doyle equation. Results show that around 65% of oil can be recovered through pyrolysis and the fraction of cyclic compounds increased with heating rate caused by enhanced C—H bonds breaking and cyclizat...