Degradation of Biomacromolecules during High‐Rate Composting of Wheat Straw–Amended Feces

• Published in: Journal of environmental quality 2001-09, Vol.30 (5), p.1675-1684
• Main Authors: Veeken, A. H. M., Adani, F., Nierop, K. G. J., Jager, P. A., Hamelers, H. V. M.
• Format: Article
• Language: English
• Subjects: Agriculture, rearing and food industries wastes; Agronomy. Soil science and plant productions; Animals; Applied sciences; Biodegradation, Environmental; Biological and medical sciences; Biological treatment of sewage sludges and wastes; Biotechnology; Cellulose; Chemical extraction; Composting; Conservation of Natural Resources; Degradation; Environment and pollution; Exact sciences and technology; Feces; Feces - chemistry; Fundamental and applied biological sciences. Psychology; Gas chromatography; Gas Chromatography-Mass Spectrometry; General agronomy. Plant production; Industrial applications and implications. Economical aspects; Ligands; Magnetic Resonance Spectroscopy; Mass spectrometry; NMR; Nuclear magnetic resonance; Organic Chemicals - metabolism; Organic compounds; Organic matter; Other nutrients. Amendments. Solid and liquid wastes. Sludges and slurries; Pollution; Proteins; Pyrolysis; Reagents; Saccharides; Soil-plant relationships. Soil fertility. Fertilization. Amendments; Swine; Temperature; Triticum; Wastes; Wheat straw
• ISSN: 0047-2425; 1537-2537
• DOI: 10.2134/jeq2001.3051675x

ABSTRACT Pig (Sus scrofa) feces, separately collected and amended with wheat straw, was composted in a tunnel reactor connected with a cooler. The composting process was monitored for 4 wk and the degradation of organic matter was studied by two chemical extraction methods, 13C cross polarization magic angle spinning (CPMAS) nuclear magnetic resonance (NMR) and pyrolysis gas chromatography–mass spectrometry (GC–MS). Wet‐chemical extraction methods were not adequate to study the degradation of specific organic compounds as the extraction reagents did not give selective separation of hemicellulose, cellulose, proteins, and lignins. A new method was proposed to calculate the contribution of four biomacromolecules (aliphatics, proteins, polysaccharides, and lignin) from the 13C CPMAS NMR spectrum. Pyrolysis GC–MS allowed identification of the composition of the biomacromolecules. The biomacromolecules showed different rates of degradation during composting. High initial degradation rates of aliphatics, hemicellulose, and proteins were observed, where aliphatics were completely degraded and hemicellulose and proteins were partly recalcitrant during the four weeks of composting. The degradation rate of cellulose was much lower and degradation was not completed within the four weeks of composting. Lignin was not degraded during the thermophilic stage of composting but started to degrade slowly during the mesophilic stage. A combination of 13C CPMAS NMR and pyrolysis GC–MS gave good qualitative and semiquantitative assessments of the degradation of biomacromolecules during composting.