IN SITU MEASUREMENT OF AMMONIA VOLATILIZATION FROM BROILER LITTER USING AN ENCLOSED AIR CHAMBER

Abstract

An experimental apparatus and analytical technique were developed for measuring and characterizing in situammonia (NH3) volatilization from broiler litter. The apparatus included an enclosed air chamber, an infrared gasanalyzer, a dew point hygrometer, and a datalogger. Airspeed in the chamber was within 12% of that measured in atypical broiler house. Ammonia flux was monitored during growout of six flocks of broilers where initial bedding materialwas either rice hulls or an equal mixture of rice hulls and pine shavings. Ammonia flux from re-used litter was six timesthat from new bedding material at the start of a growout. Mean and maximum NH3 flux during growouts were 149 and314 mg NH3-N/m2-h on new bedding and 208 and 271 mg NH3-N/m2-h on re-used litter, respectively. Randomexperimental error for the flux measurement technique was estimated to be 32 mg NH3-N/m2-h. Systematic variation wasfound in transverse measurements across the width of a broiler house with flux greatest adjacent to the water lines. Theseresults may be useful in designing economical strategies to control NH3.