The results of the research on the amount of water evaporation from composting facilities operated in swine farms are below.
The number of swine per a farm was 1433 head/farm for a Simple Composting Facility(SCF) and 3500 head/farm for a Escalator composting facility(ECF) system. The capacities of the SCF and the ECF were 0.33m³/head and 0.25m³/head, respectively. The ECF had 24.2% less capacity than the SCF. The average water contents in the swine manure for the CP and the ECF of the surveyed farms were 86.8% and 85.7%, respectively, which revealed the ECF had 1.3% less average water content than the SCF. Daily water inputs into the SCF and the ECF were 4.1kg/m³/day and 6.5kg/m³/day, respectively. The ECF had approximately 36.9% higher water input than the SCF. Fermentation temperatures during the composting period for the SCF and the ECF were up to 45℃ and 70℃, respectively.
The decreases in water contents per each square meter for the SCF and the ECF were 3.7kg and 5.2kg, respectively. The ECF lost approximately 28.8% more water content than the ECF, which would be caused by the difference of fermentation temperature between two systems.
Fertilizer components after composting were examined. Nitrogen contents of the SCF and the ECF were similar(0.84% and 0.86%, respectively) and P₂O5 contents were 0.78% and 0.74%, respectively, showing the SCF had slightly higher content than the ECF. However, OM and OM/N did not show the difference between two systems.
Hence, efforts to increase composting efficiency with considerations of the water content of swine manure, fermentation temperature, and water evaporation potential should be done when the SCF and the ECF were used in swine farms.