Enhancement of Coal Quality by using Bioextracts of Carissa carandas Fruits

The major problem faced by coal fired power stations in India is high ash content. Commercially it is big loss to transport high ash content coal as leads to higher specific coal consumption in addition to environmental issues like suspended particulate matter. This research study aims to develop a chemical method using weak organic acids from plant extracts to reduce ash content in the coal. In this context Carissa Carandas fruit extract is used to treat with coal samples at optimum conditions and found this bio extract effectively leaches ash from coals. This treatment process is applied to different coals used for combustion at Rayalaseema thermal power project, Kadapa, India and found 6 to 7 % reduction in ash content and increased gross calorific value of coal by more than 600 units. These findings are proved in proximate and ultimate coal analysis and supported by IR and XRD spectral studies. By using the optimized conditions of the laboratory scale, a prototype simulator is designed. This coal beneficiation method resulting in accomplishment of technical, environmental most importantly commercial benefits as cost of generation has reduced from Rs 2.66 to Rs 2.32 per unit of energy. This results in the total savings of approximately more than 178 crore per year in 600 MW unit alone, in an eco friendly manner.