Effect of biochemical composition on odor emission potential of biowaste during aerobic biodegradation

This study aimed to identify the individual effect of biochemical composition on odor emission potential of biowaste during aerobic biodegradation. Three kinds of typical mixed wastes, including vegetable-fruit waste, garden waste, and protein-rich waste, were tested for emission quantity of seven common odorous families within 21 days of biodegradation under aerobic conditions. The cumulative odor yields (COY) were as follows: protein-rich waste (2408 μg g^-1 DM) > vegetable-fruit waste (1169 μg g^-1 DM) > garden waste (62 μg g^-1 DM), and their cumulative odor intensity were 16,701, 1888, and 212 g^-1 DM, respectively. The odor emission of vegetable-fruit waste mainly occurred in the first 3 days, accounting for 91.7% COY, and the predominant contributor to odor intensity (PCOI) were terpenes and sulfur compounds. With regard to garden waste, the odor emission rate was the highest on day 1 (22.4 μg g^-1 DM d^-1) and then rapidly decreased, and the PCOI were aldehydes. The odor emission rate of protein-rich waste increased gradually in the initial stage and reached the peak value on day 10 (661.9 μg g^-1 DM d^-1), and its PCOI were sulfur compounds. This study revealed for the first time the relationship between the odor emission potential of biowaste and its characteristic of biochemical composition, then proposed potential application for odor pollution control during aerobic composting.