Experimental Studies on Effects of Selected Species of Fungi on Aerobic Composting of Sugar Pressmud

Abstract

Pressmud is one of the most highly complex organic by-products generated from sugar industry. Due to its complex nature, disposal of the pressmud is difficult without affecting the surrounding environment. Pressmud has a high potential of converting itself into a good quality organic manure with proper management, through the aerobic composting process. This study is a part of major research work which focuses on recycling of nutrients and safe disposal of two of the most complex by-products: sugar pressmud and distillery spent wash through the aerobic composting process. The main objective of this study is to determine the effect of a commercially available microbial consortium on aerobic composting of pressmud. The selected microbial consortium includes four species of fungi: Phaenerochaete, Trichoderma Virdea, Aspergillus Niger, Pleurotus. These are capable of degrading complex organic matter with lignocellulosic characteristics. Five composting mixtures were prepared for this study, with four composting mixtures of individual species of fungus and the fifth composting mixture with all four fungi species. Aerobic composting was carried out in PVC reactors with 7 kg of pressmud as a base material, 1 % (w/w) of optimum dosage for microbial consortium and 5% (w/w) of digested cow dung. The study was carried in the pre-monsoon season over a period of 50 days. Aeration was provided with mixing of the contents at every three days interval, and also, water was added to maintain the moisture content in the optimum range. Representative samples were collected and analyzed for various physic-chemical parameters. Further, these results were compared with the standards prescribed by Fertilizer Control Order (FCO), Ministry of Agriculture, Government of India, to assess the nutrient content of the prepared compost. The prepared compost from CM-V showed a pH of 7.62, EC of 3.67 dS/m, TOC of 17.64 %, TKN of 2.24 %, phosphorus of 4.93 %, potassium of 1.11 %, iron of 72.20 mg/kg and C/N ratio of 7.86. Hence, it can be concluded that CM-V has satisfactory overall nutrient content in most of the parameters. But further studies are to be conducted in a large scale to assess the evolution of heat during the composting process and its effects on duration of composting.