Characteristics of vertical distribution of oxygen concentration and consumption rate in aerobic static composting

It is of important to improve the composting techniques and the structure of the pile to know the vertical distribution of oxygen concentration and oxygen consumption rate. The characteristics of oxygen supplement and consumption were analyzed in aerobic static composting. The oxygen concentration at different parts of the pile could increase from 17% to 20.6% after ventilation during different stages of composting. The decrease rate of oxygen concentration at the upper part was faster than that of the middle and bottom of the pile, and the oxygen concentration at the upper part was lower, which could be 3%. After same time of stopping ventilation, the oxygen concentration before ventilation increased along with the proceeding of composting. The oxygen concentration before ventilation could be upper 10% at the middle and bottom of the pile after the middle stage of high temperature, and the decrease rate of oxygen concentration declined too.