Management of Biogas spent slurry for hastening the composting of agro residues

• Published in: Carbon science and technology Vol. 7; no. 2; pp. 25 - 32
• Main Authors: G. S. Geeta, M. Ashwini, T. H. Shankarappa
• Format: Journal Article
• Language: English
• Published: Applied Science Innovations Private Limited 01-04-2015
• Subjects: Biogas spent slurry; enrichment
• ISSN: 0974-0546; 0974-0546

The demand for energy and the fertilizers are ever increasing. Organic farming has many advantages looking to the environment pollution, unproductive soil, less yields etc. By installation of a biogas plant serves both the purposes of meeting the fuel as well as obtaining manures. The organic manures need to be added in bulk to meet the nutrient demands of the crop as it is not in concentrated form like chemical fertilizers. Hence, biogas spent slurry is the best alternate for hastening the compost preparation of abundantly available crop residues as well as obtaining enriched compost as conventional method takes long time. Moreover, slurry is composed of major nutrients besides enzymes and a rich microflora. Based on the preliminary results, the present study was conducted at farmer’s field to know whether slurry could be used for degradation of agro residues. One ton of crop residues that included banana waste, sunflower and maize waste, leaf litter of horticultural crops were inoculated individually with 60 L of spent slurry along with consortia of degrading fungi and P-solubilising bacteria. After a retention period of 60 days, nutrients were analysed. The cultures along with slurry indicated 1.5 - 1.96% N with reduction in C:N ratio between 1.6 - 1.82. The micronutrients also increased. Thus, it was concluded that efficient use of spent slurry can be made besides utilising the crop residues and the product for organic cultivation.