Characteristics of Municipal Solid Waste Composting and Determination of Composting Maturation

The characteristics of thermophilic aerobic composting process for municipal solid waste were studied. The changes of pH and organic matter content, the infrared spectra of organic matter before and after composting, the development of humification, and the toxicity for the seed were investigated. The results indicated that: the pH quickly increased and then decreased, stabilized in the neutral range; organic matter degradation occurred mainly in the first 30 days of high temperature rapid composting stage, indicating the high temperature phase played the main role in the organic matter degradation; the increases of humus, fulvic acid, humic acid and humic acid/fulvic acid ratio also showed the conversion of organic matters to humus. Composting decreased the matters inhibiting seed germination and weakened the toxicity for the plant, and the sample reached maturity through composting.