Investigation of aerobic solid fraction fermentation process parameters for organic material.

Abstract

The parameters of aerobic solid fraction fermentation of a mixture of solid swine manure, poultry litter with addition of carbon containing plant materials have been investigated. A bioreactor design has been developed. Qualitative rating of the process and end product has been made by measuring such parameters as: process temperature, mixing process, air supply for aeration, pH and ash. A rational mixing mode for mixture has been found by investigating the dependency of temperature and costs time for fermentation of a mixture. The effective rotational speed of the reactor with periodic stirring and aeration of the compost is 10 rpm. This mode allows providing qualitative mixing and saturation of compost with air, to maintain the temperature range of thermophilic mode within 61-63 ºC. With this mode of operation, the full fermentation time of the compost is 8 days. Adding wood shavings and straw to the fermented mixture allows increasing the organic value of the resulting compost. The final compost was characterized by good qualitative characteristics, a significant level of humification and no odor emissions. This method of aerobic solid fraction fermentation of organic material represents an effective, low cost approach that could be an interesting opportunity for animal farms.