Impacts of different sized lab-based reactors on the aerobic composting of chicken manure

The aerobic composting with sawdust and chicken manure as raw material was carried out to study the effect of different sized lab-based reactors(18, 24, 30 and 42 L) on dynamic changes of temperature, total-C, C/N ratio, water-soluble organic carbon and microbial population during the high speed (12 d). The results showed that the duration of high temperature of 50℃ and 55℃ all exceeded seven days and the compost conformed to the sanitary standard of the aerobic composting; the results showed that the time of maintaining high temperature of above 50℃ exceeded seven days, and with the increased volume of compost, the time of sustained high temperature lengthened; with the changes of the total carbon content, water-soluble organic carbon content and the C/N ratio of the test composting maturity, the composting processes of 30 and 42 L were more rapid than 18 L and 24 L; in the composting process, the changing trend of bacteria quantity is rising after the first drop, fungi quantity rapidly declined in the high-temperature phase, actinomycosis quantity was rising, and 30 L and 42 L of the actinomycosis quantity were more than 24 L and 18 L in the high temperature period, significantly. The minimum valid size of composting equipment should be above 30 L, in a environment without any outside heating.