Effect of manure on ammonia emission from a fattening pig house with partly slatted floor

The effect of manure on ammonia (NH3) emission was assessed with the manure in a deep pit and the manure on a partly slatted floor in a commercial fat tening pig house. The manure in the pit was measured with its depth. The ma nure on the floor was determined with floor contamination that was the prop ortion of the floor surface covered by a mixture of urine and faeces. Ammon ia emission from an exhaust chimney was continuously measured for 135 days with a NOx analyser and a full-size ventilation rate sensor. Measurement da ta were processed and 900 steady-state data subsets were extracted. The ste ady-state data were used to investigate the effect of manure on the NH, emi ssion. There was no good relationship established between the NH3 emission rate and the manure depth (correlation coefficient r = - 0.143). However, t he NH3 emission rate had a high correlation coefficient (r = 0.852) with th e floor contamination. A linear equation was built for the relationship bet ween the NH3 emission and the floor contamination. it was further found tha t the floor contamination itself was influenced by the weight of pigs and t he inside room temperature. A model was developed to calculate the floor co ntamination as a function of the weight of pigs and the inside temperature (R-2 = 0.811). With higher floor contamination values in the house, the ven tilation rate and the inside room temperature had stronger influence on the NH3 emission rate. (C) 1999 Elsevier Science B.V. All rights reserved.