Dr. Sunil J Kulkarni
Faculty, Chemical Engineering Department,
Datta Meghe College of Engineering, Airoli,
Navi Mumbai
Mrs.Meera T. Sose
Faculty, Chemical Engineering Department,
Datta Meghe College of Engineering, Airoli,
Navi Mumbai
Dr. R. W. Gaikwad
Professor & Head, Department of Chemical Engineering
Pravara Rural Engineering College, Loni
First chapter introduces us to the subject and content of the book. In the second chapter various important aspects of waste treatment methods for solids are discussed. These include aerobic composting, anaerobic treatments and vermicomposting. The treatment of solid waste can be carried out by various methods like sanitary landfill, composting and incineration. Aerobic and anaerobic digestion methods have their own advantages and disadvantages. Aerobic method needs diffusion of air through waste. Also sizeable amount of sludge is produced in aerobic method. Aerobic methods are most common in the waste treatment because of simplicity and effective treatment. The studies reveal that it is important to achieve an optimal system for processing organic waste. Vermicomposting is one of the most practiced methods for domestic and household solid waste treatment. In this, earthworms feed on anything that is biodegradable.
In the third chapter, work on aerobic composting is explained. Studies are carried out on variation in parameters like pH, moisture content, organic content and temperature. The parameters were measured by using conventional chemical analysis methods in laboratory. pH of the composting material changed from 6 at an ambient stage to 5.5 at mesophilic stage. The pH rapidly increased to 8.5 during thermophilic phase. It again fell to 6 during cooling period. Moisture content at ambient stage was 58 percent. This afterwards changed to 40 percent during cooling stage. The organic content decreases from ambient to mesophilic stage. This cooling indicates decomposition of organic waste. The temperature increased from 25 oC in ambient stage to 40oC in mesophilic stage. It increases to 54oC in thermophilic stage.
In the fourth chapter, pilot plant studies on vermicomposting are explained. Vermicomposting offers better solution to the solid waste treatment. The area required for the treatment in vermicomposting is less than aerobic digestion method. The time required is less. Also the odour problem is solved since the waste is covered of number of layers of oil and other layers. The current research aims at treating the solid waste by vermicomposting method and analyzing the effects on moisture content, organic content, temperature and pH with time.
In fifth chapter, actual running plant is studied for various parameters. In the this investigation performance of anexisting vermicomposting plant is analyzed. During performance evaluation of vermicomposting plant, the changes in biophysiochemical parameters were computed. The vermicomposting process requires a moisture content of 30 to 50%. There was visible effect of vermicomposting on the losses of organic content. Also the percentage of organic content decreased during theperiod of vermicomposting. This implies that the decomposition of waste by worms population. There was decrease in the pH during vermicomposting. The process is most effective between pH ranges 6.4 to 7.6.