Volume 13 Part 1 Article 24
Title: Odorous sulfur compounds emitted during conventional outdoor- and during indoor- composting
Authors: H.J.M. op den Camp, R.J.L. Derikx, C. van der Drift, G.D. Vogels and L.J.L.D. van Griensven
Large-scale composting facilities are known to cause environmental problems, mainly through the pungent air emitted by the composting material. In air samples taken above windrows, a number of volatile compounds were identified by means of the coupled technique of gas chromatography and mass spectrography. Among the compounds identified, sulfur-containing compounds (H2S, COS, CH3SH, CS2, (CH3)2S, CH3)2S2 and (CH3)2S3) are the most conspicuous in causing nuisance. Quantification of these compounds was performed by concentrating a relatively small air sample on Tenax GC. The sampling method appeared to be very useful under field conditions. During the composting process the concentration of the volatile sulfur compounds in the evolving air ranged from 1 to 35 µmol/m3. Highest concentrations were found at the end of the windrow phase. The influence of temperature and various additions on the production of volatile sulfur compounds were tested on laboratory scale. The production of H2S, COS, CH3SH and (CH3)2S was proven to be a biological process with an optimal temperature of about 55°C. The formation of CS2 and (CH3)2S2 was shown to be a nonbiological process. The emission of volatile sulfur compounds during the indoor preparation of mushroom compost appeared to be remarkably reduced (about 90%) as compared to the conventional outdoor process. Introduction of this indoor composting process would result in a significant reduction in environmental pollution.Please login to download the PDF for this proceeding.