Moisture balance and tracer gas technique for ventilation rates measurement and greenhouse gases and ammonia emissions quantification in naturally ventilated buildings

Abstract

Experiments were performed to study the ventilation rates in a naturally ventilated animal building through four summer seasons and three winter seasons. The ventilation rates were determined using moisture (H 2O) balance, tracer gas technique (TGT) and CO 2-balance. The statistical analyses were correlation analysis, regression model and t-test. Continuous measurements of gaseous concentrations (NH 3, CH 4, CO 2 and N 2O), temperature and relative humidity inside and outside the building were performed. The H 2O-balance showed reliable results through winter seasons and acceptable results to some extent through summer seasons. The CO 2-balance showed unexpected high differences to the other methods in some cases. The TGT showed reliable results compared to H 2O-balance and CO 2-balance. The air exchange rates (AERs) were 37.2, 61.6 and 63 h −1 through summer seasons, and 40.3, 38.9 and 60.5 h −1 through winter seasons subject to H 2O-balance, TGT and CO 2-balance, respectively. The emission rates through summer seasons, subject to TGT, were 191, 855, 73,877 and 45.6 g d −1 AU −1; and through winter seasons were 88, 463, 55,976 and 47.3 g d −1 AU −1, for NH 3, CH 4, CO 2 and N 2O, respectively.