TG/DSC-FTIR and Py-GC investigation on pyrolysis characteristics of petrochemical wastewater sludge

Abstract

The pyrolysis characteristics of petrochemical wastewater sludge (PS) were evaluated using TG/DSC-FTIR and fixed-bed reactor with GC. TGA experiments indicated that the pyrolysis of PS proceeded in three phases, and the thermographs shifted to higher temperatures with increasing heating rate. Chars FTIR showed that the absorption of O–H, C–H, CO and C–C decreased with pyrolysis temperatures increasing. Gases FTIR correspondingly showed that H2O, CO, and CH4 generated at higher temperatures. For the fixed-bed reactor tests, H2 and CO were relatively higher in the pyrolysis gases, and CH4 was negligible at 436K. The kinetic triplets of PS pyrolysis were estimated by Flynn–Wall–Ozawa, Kissinger–Akahira–Sunose, and integral master-plots method. The results suggested that the most potential kinetic models for the first and second phase were the order reaction model, while the random nucleation and nuclei growth model for the third phase.