Factors and characteristics of ammonia, hydrogen sulfide, carbon dioxide, and particulate matter emissions from two manure-belt layer hen houses

Abstract Manure-belt layer hen houses are a relatively newer design and are replacing the old high-rise layer hen houses for egg production in USA. However, reliable aerial pollutant emission data from comprehensive and long-term on-farm monitoring at manure-belt houses are scarce. This paper reports the emission factors and characteristics of ammonia (NH 3 ), hydrogen sulfide (H 2 S), carbon dioxide (CO 2 ), and particulate matter (PM 10 ) from two 250,000-bird capacity manure-belt layer hen houses (B-A and B-B) in northern Indiana, USA. The 2-year continuous field monitoring followed the Quality Assurance Project Plan of the National Air Emission Monitoring Study (NAEMS). Only days with more than 18 h (or 75%) of valid data were reported to avoid biased emission calculation. The results of 2-year average daily mean (ADM) gas emissions per hen from the two houses, excluding emissions from their manure shed, were 0.280 g for NH 3 , 1.952 mg for H 2 S, and 103.2 g for CO 2 . They were 67% lower for NH 3 , 77% higher for H 2 S, and 10% higher for CO 2 compared with reported emissions from high-rise layer hen houses. Emissions of NH 3 and CO 2 exhibited evident seasonal variations. They were higher in winter than in summer and followed the NH 3 and CO 2 concentration seasonal patterns. Annual emission differences were observed for all the four pollutants. Reduced emissions of the three gases were shown during periods of layer hen molting and flock replacement. The 2-year ADM PM 10 emission from B-B was 25.2 mg d −1 hen −1 . A unique weekly PM 10 emission pattern was identified for both houses. It was characterized with much lower Sunday emissions compared with the other single-day emissions of the week and was related to the weekly schedule of in-house production operations, including maintenance and cleaning.