INFLUENCE OF AERATION RATE AND LIQUID TEMPERATURE ON AMMONIA EMISSION RATE AND MANURE DEGRADATION IN BATCH AEROBIC TREATMENT

Abstract

The influence of aeration rates (26, 63, and 100 .g O2 g VS-1 min-1) at different temperatures (5C, 15C, and25C) on ammonia emission and breakdown of organic materials was studied using 15.3 L batch reactors for 21 days. Theremoval of total Kjeldahl nitrogen (TKN) ranged from 9.7% to 37.7% during the experiment, with higher values correspondingto higher manure temperatures and aeration rates. Ammonia loss ranged from 0.7% to 25.8% of initial TKN and increasedwith increase in manure temperature and aeration rate. In a similar pattern, the ratio of volatilized ammonia gas to removedTKN varied from 6.5 to 68.5. In addition, high BOD5 removal was also observed when both the temperature and the aerationrate were high, with the exception for airflow rates between 26 and 63 .g O2 g VS-1 min-1 for the manure at temperaturesbetween 5C and 15C. The combinations of high aeration rate (100 .g O2 g VS-1 min-1) with low temperature (5C) or lowaeration rate (26 .g O2 g VS-1 min-1) with high temperature (15C to 25C) were found to be desirable to reduce ammoniaemission while still achieving satisfactory BOD5 removal at the same time.