The Characteristics and Kinetics of Municipal Solid Waste and Coal Co-Combustion

J. J. Liu†, ‡, §, R. L. Man†, §*, J. S. Li ‡*, L. Chen‡, H. Zhang‡, J. Y. Peng‡, Y. Luo‡, H. Xi‡, & S.  X. Ma††

†School of Chemistry Engineering, Central South University, Changsha City, Hunan Province, China,
‡Changsha Environmental Protection College, Changsha City, Hunan Province, China,
§Key Laboratory of Nonferrous Metal Resource Chemistry, Central South University, Changsha City, China,
††South China Institute of Environmental Sciences, MEP, Guangzhou, China

ABSTRACT: The characteristics and kinetics of the co-combustion of municipal solid waste (MSW) and coal were experimentally studied using a thermal gravimetric analyzer. Combustion characteristics of the mixed samples of various combinations of MSW and coal were analyzed using Coats-Redfern combustion kinetics; the results showed that the MSW and coal in the mixes essentially maintained their respective combustion characteristics during the co-combustion process; the MSW in the mixes promoted the combustion characteristics of coal in the mixes. The co-combustion of the MSW-coal mixes exhibited two combustion stages, following second-order kinetics and first-order kinetics, respectively; the combustion of coal only exhibited one combustion stage that followed first-order kinetics. There existed a kinetic compensation effect between the activation energy Ea and pre-exponential factor A in the co-combustion of the MSW-coal mixes.

Keywords: Municipal solid waste; Coal; Co-combustion; Coats-redfern combustion kinetics; Thermo gravimetric analysis (tga).