Comparison of a variety of physico-chemical techniques in the chronological characterization of a compost from municipal wastes

Abstract

The degree of stability and maturity of the organic matter are fundamental features of the chemical characterization of compost. These characteristics are related to the extensive formation of aromatic structures and of oxygen-containing functional groups. The increase of the amount of these chemical moieties can be assessed by different analytical methodologies, based on thermal, spectrophotometric, and electrochemical techniques. In order to compare the ability of the most used methodologies to differentiate compost at different composting stages, results from the direct characterization of solid samples and their extracts are reported. A total of 108 parameters from the characterization of a compost at four composting stages were treated by a ComDim analysis. The relevance of the analytical techniques for monitoring composting was established by considering the absolute value of the loadings and that results vary in a single way along the process.