Concentration of methane gas at different levels of the animal shed

Abstract

Methane is one of the greenhouse gasses (GHG) that is responsible for the current increase in the temperature and the climate system of earth. Methane is the second most abundant GHG, right after CO2. CH4 is 25 times more potent than CO2 when it comes to trapping heat in the atmosphere and also, it accounts for about 20% of global emissions. Ruminant livestock can produce 250 to 500 L of methane per day. This study was carried out to determine the differences in concentration of methane at different parts of an animal shed. Gas was collected at different periods of time from different locations of the shed. There were four categories for this study, concentration at different heights inside the animal shed, concentration at different times of the day, concentration at an altitude that was at the level of the roof of the shed where a pipe was attached compared to a higher altitude above it where the pipe ended and concentration when the spaces around the pipe was blocked and when it was not. The current study indicated that the concentration of methane is highest near the roof (62.69 ppm), less at the middle (61.86 ppm) and least at the bottom (54.39 ppm). It also showed that the concentration of accumulated methane was higher at noon (58.48 ppm) than in the morning (46.18 ppm). Concentration of methane near the roof where the bottom of the pipe was attached was higher (59.65 ppm) compared to the top of the pipe situated on the roof of the adjacent building (46.33 ppm). Concentration of methane when the empty spaces around the pipe was covered was lower (51.14 ppm) than when it was uncovered (51.94 ppm). It can be interpreted from the study that methane concentration has variations at different levels and at different times of the day inside the shed. The highest concentration of methane can be found near the level of the roof and at noon.