Effects of Temperature and Initial Moisture Content on the Composting Rate of Paper Mill Sludge and Broiler Litter

The effects of temperature and initial moisture content on the rate of composting of paper mill sludge (a waste product of the paper making process) with poultry broiler litter were investigated using a bench scale composting system. Tests were conducted at 5 initial moisture contents (32.6, 37.4, 42.2, 47.9, and 53.5 %, wb.) and 5 temperatures (37.8, 41.5, 53.8, 59.7, and 64.3 oC). Each treatment was replicated two times. The system was monitored for temperature, O2 uptake, CO2 generation, mass reduction, and moisture content. A first order kinetic model was used to predict decomposition rates of paper mill sludge with broiler litter. Regression analysis applied to data using a 2-D Gaussian model indicated that the optimum initial moisture was 44 %, wb. and the optimal composting temperature was 57 oC.