Abstract
Rice husk, sawdust, and shredded paper were each mixed at a rate of 15% and 30% by dry weight into dairy manure as bulking materials to investigate their potential for reducing ammonia emissions. Composting was carried out in a 1-L reactor, and mixture temperatures were controlled to mimic the temperature of manure composting. Mixing the bulking materials into the dairy manure reduced mass of ammonia emitted during composting. Relative ammonia emissions based on manure nitrogen from mixtures bulked with sawdust or shredded paper were the same as those from unbulked manure, but emissions from rice husk mixtures were greater than those from unbulked manure. These results suggest that bulking materials do not reduce ammonia emissions at the mixing rates used.
