Application of thermogravimetric analysis to study the thermal degradation of solid and liquid organic wastes

In this work, the thermolysis of composite binary mixtures of refinery or coal-processing waste with waste biomass and D-grade (long-flame) coal was analyzed in order to increase the efficiency of the cothermolysis of chemically different organic wastes mainly because of the synergism of the thermolysis of mixture components and, correspondingly, the selectivity of formation of high-quality by-products (solid, gaseous, or liquid). A new approach to the analysis of thermogravimetric data was proposed and developed as applied to complex binary mixtures of carbon-containing materials. This approach was based on (1) the preliminary separation of the thermal degradation of individual carbon-containing mixture components into individual structural constituents and (2) the monitoring of the conversion of each particular structure fragment as a constituent of the mixtures in the course of the cothermolysis of the mixtures of starting components. Based on the approach developed, data on the main synergism effects in the course of cothermolysis in the binary test systems were obtained: the temperature regions of the appearance of these effects were distinguished, the main conclusions were made with respect to particular structure fragments in complex organic wastes responsible for the interaction of components in composite systems, and the directions (positive or negative) of changes in the yields of solid by-products and the degrees of effects (difference between the yields of cothermolysis by-products in each particular region of the appearance of synergistic effects in the systems) were determined. Additionally, the influence of alkali metal carbonate additives on synergistic effects in the interaction between binary system components under the process conditions of cothermolysis was analyzed.