Control of dimethyl sulfide and dimethyl disulfide odors during pig manure composting using nitrogen amendment.

Effects of nitrogen electron acceptors on dimethyl sulfide (MeS) and dimethyl disulfide (MeSS) odor emission during composting was investigated. The chemicals and doses used included sodium nitrate (NO at 10mM, 20mM and 40mM), sodium nitrite (NO at 10mM, 20mM and 40mM) and sodium nitrite (10mM, 20mM and 40mM) with hexaammonium heptamolybdate tetrahydrate (HHT). The results showed that the addition of these chemicals restricted the emission of MeS and MeSS. The emission reduction effect of NO was greater than NO at the same dosage. A greater reduction was observed when HHT was also added. With 2mM HHT+40mM NO addition, the emission of MeS and MeSS was reduced by 92.3% and 82.3%, respectively. Comparison of compost maturity indices for treated and untreated composts indicated that none of the additives adversely affected compost quality. These results indicate that nitrogen chemical addition may provide an efficient method to control sulfur odors during composting.