Water content of a Brazilian refinery oil sludge and its influence on pyrolysis enthalpy by thermal analysis

Residual oil sludges represent an environmental problem in the oil industry and need a proper destination in order to allow sustainable industrial processes when exploring natural resources. In the present paper, the influence of the water content on the oil sludge pyrolysis process was studied by thermal analysis. A method using thermogravimetry on calcined mass basis was developed to estimate the water content of oil sludges. The water present in the sludge vaporizes during the first thermal processing stage, interfering in the initial process of the organic components pyrolysis and increasing the total oil sludge pyrolysis enthalpy. By quantitative differential thermal analysis (DTA) it can be seen that the water content of the sludge may significantly affect the thermal balance of its industrial pyrolysis process.