Pyrolysis and combustion of Russian mixed sludge and subsequent gaseous emissions: Analysis and kinetic modeling

Abstract

The Arkhangelsk Region, North-West of the Russian Federation, has an important pulp and paper production whose plants generate industrial sludge which is mixed with municipal sludge. Thermal degradations under nitrogen or synthetic air of this mixed sludge were performed under four low temperature ramps of 5, 10, 15 and 20 °C/min. Kinetic modeling of the pyrolysis and combustion experiments was performed applying the Extended Independent Parallel Reaction model with five constituents. Different error measurements were computed to validate the optimal values of the kinetic parameters. Complementary combustion experiments were performed in a horizontal oven to continuously measure the main gaseous emissions (CO, CO2, THC, NO and NO2). The NO and NO2 emissions were observed at very low amounts. The curves associated with the CO, CO2 and THC emissions were observed to well superimpose with the mass rate curve of the corresponding combustion experiment performed in the thermobalance, but with a small time delay.