| Abstrakt: |
The present investigation aims to develop the green methodology based on phytoextracts to enrich coal quality in thermal power stations. High ash content in domestic coals is one of the serious problems in thermal power generation in India. This results in high specific coal consumption, transportation losses, environmental issues, increase in operational problems in generating stations, etc. Coal beneficiation technologies are based on physical and chemical methods. The chemical methods of reducing ash content are costly, hazardous, and difficult to handle in large scale. In this context, "biomethods" based on treating the coal with "bio-extracts" of the plants to increase the quality of coal are interesting. The bio-extract of Citrus limon plant is identified to effectively decrease the content of metal oxides (ash) in 212-μ fine coal powder on digestion under "condensate distillation (100 °C)" for optimum period of 1.0 h in the pH range 4–6. The method is applied to the coals of various sources used in Dr Narla Tata Rao Thermal Power Station (Dr NTTPS), Vijayawada, India. The percentage of ash content in the coal is decreased to the designed levels of the boilers of Dr NTTPS, and thereby, optimum combinations of fixed carbon with volatile matter are achieved for ideal combustion. The coals before and after treatment are characterized by XRD and IR analysis in addition to proximate and ultimate analysis. A prototype simulator is designed with the optimum conditions established at the laboratory scale. To apply the finding for the entire power station, modifications are suggested in the crusher house of thermal power station. The developed method is effective in reducing the cost of power generation from Rs 2.38 to Rs 1.91 per unit of power. This results in savings of many crores of rupees per year. [ABSTRACT FROM AUTHOR] |
Full text from SpringerLink