Thermal Degradation of Household Solid Waste in the Town of Abomey-Calavi in Benin: Kinetic Study

Abstract

Thermal behavior of household waste can be improved by knowing thermal degradation kinetics for the optimal design and operation of pyrolysis process. In the present study, Thermogravimetric analysis has been used for dynamic kinetic study of pyrolysis of waste cardboard, wood, and household waste of Abomey-Calavi city in Benin under Argon atmosphere at different heating rates 5–50 °C min−1. For facilitating the laboratory study of household, a model waste (MW) based on wood (88 %), cardboard (7 %) and plastic (5 %) was developed. The kinetic of model waste was studied with Friedman isoconversional method. The thermal degradation of MW is processed in two steps: the first step between 200 and 400 °C and second step between 400 and 600 °C. The difference of mass loss between experimental and theoretical ones (calculated as arithmetic sums of those from each separated component) was used as a criterion of synergetic effect. The experimental results indicated that a low synergetic effect existed between plastic and cellulosic materials during the pyrolysis of MW. Based on TG and DTG data with different heating rates, the kinetics parameters, especially activation energy were calculated using simple step kinetic model for reaction order n = 1. Reasonable fits of data to straight lines in kinetic study plot indicate that the reaction order n = 1 used for kinetic of non-isothermal degradation of the household waste of Abomey-Calavi city in Benin is accepted.