Composting is an aerobic microbiological process facilitated by diverse microbial groups supplementing significant fertilizer quality to soil. Our current society is faced with the problem of managing growing quantities of organic municipal waste. In order to increase the biodegradative rates and lower the emission of noxious gases, introduction of lignocelluloytic fungi and diazotropic microbes was found to be beneficial.
In this study we initially isolated Aspergillus niger, a lignocellulolytic fungi and diazotrophic Azotobacter sp from soil by serial dilution method. Compost samples collected from commercial site and lab scale preparations were supplemented with pellet preparations of Aspergillus niger and Azotobacter sp in variable run off trays set up with adequate substrates for biodegradation. Control samples(without added inoculums) were also maintained. The C/N ratios, temperature and pH of the samples were analyzed and compared with the control samples.
Compost preparations supplemented with Aspergillus niger and Azotobacter sp retained a higher temperature range of 37-38oC suggesting a maximized biodegradation rate. pH values was maintained at 6.8-7 in the maturation stage of the compost. More significantly C/N ratio of the finished lab compost and commercial compost was in accordance
to 30:1 when compared to one week old commercial sample which indicated an inappropriate 14:1 ratio.