MEASURING AMMONIA AND HYDROGEN SULFIDE EMITTED FROM MANURE STORAGE FACILITIES

Abstract

A modified method of trapping ammonia and hydrogen sulfide for determining ammonia and hydrogen sulfideemission from manure storage facilities was developed and tested. This method used two stages of a two-trap series, eachstage consisted of a vacuum trap followed by an adsorbing flask. The first stage contained 1 N sulfuric acid for selectiveabsorption of ammonia and amines; and the second stage consisted of 0.1 N zinc acetate in 0.1 N sodium hydroxidesolution to absorb and preserve the evolved hydrogen sulfide. Since the two trapping stages are arranged sequentially,ammonia and hydrogen sulfide can be measured simultaneously. Exhaust gases from the manure storage tank in thelaboratory were sampled and then the trapping solutions were analyzed for ammonia, using distillation procedures, andfor hydrogen sulfide, using the titration method. The new apparatus completely trapped the ammonia and hydrogen sulfideemitted, so is suitable, by adjusting the sampling time and air-flow rate, for measuring a wide range of emissionconcentrations. This method is simple to use and easy to operate in a laboratory, and can be possibly extended to fieldmonitoring of ammonia and hydrogen sulfide emissions, which would provide a low cost quantification of odor-reducingpractices in animal waste storage facilities.