Estimation of Power Generation Potential of Non- Woody Biomass and Coal – Biomass Mixed Briquettes

Abstract

In view of energy and environmental problems associated with the use of fossil fuels (coal, petroleum and gas) in power generation, an increasing attention is being paid world-over by the scientists and technocrats for the utilisation of renewable energy sources in power generation, metallurgical industries etc. There are various type of renewable energy sources such as solar, wind, hydropower, biomass energy etc. out of these renewable energy sources, biomass is more economically viable for almost all the continents in the world. Biomass is a carbonaceous material and provides both the thermal energy and reduction for oxides, where as other renewable energy sources can meet our thermal need only. Amongst all the solid fuel like coal etc. biomass is the purest fuel consisting of very lesser amount of ash materials. The power generation potential data for renewable energy sources in India clearly indicates that the biomass has potential to generate more than 17000 MW of electricity per year in India. However, the country is locking in exploitation of biomass in power generation. Till date, India has been capable to generate only 2000 MW (approx.) of electricity per year in spite of declaration of several incentives by the govt. of India. Hence, there is an argent need to increase the utilization of biomass in power generation. The present project work is a positive step towards energy and environmental problems facing the world. The presently selected forestry biomass species has no any commercial use and are underutilized.
Presently, co-firing (coal + biomass) has been proved to be more attractive and economically viable technique for power generation. In the present work, briquettes were prepared by mixing non-coking coal from Orissa mines and the related biomass species in different ratio (coal: biomass = 95:05, 90:10, 85:15, 80:20). The objectives have been to examine their energy values and power generation potential.
3rd chapter of this theses deal with the experimental work carried out in completion of this project work. The experimental works included determination of proximate analysis, energy value & ash fusion temperature (AFT) of different components of biomass, coal & there mixture.
The results & discussion of the experimental work have been outlined in chapter 3 of the thesis. The results has indicated that Cassia Tora biomass species has somewhat higher ash and lower fixed carbon contents then these of Gulmohar biomass species, energy values of Gulmohar biomass species were found to be little bit higher than that of Cassia Tora biomass. The proximate analysis results of studied coal proved it of F- grade.
As it is evident from result, an increase in biomass content (wood/leaf/nascent branch), in general, in the briquetted increases the energy values of the resulting briquettes. From Volatile Matter (VM) & Fixed Carbon result, it appears that the volatile matter contents is also playing significant role in affecting the energy value of the briquettes in addition to fixed carbon. Among the four AFTs (IDT, ST, HT & FT), softening temperature of ash is most important for boiler operation. The results have indicated that both biomass species have more or less same softening temperature but lower than that of coal. Increase in biomass content in the briquette on rang studied has slightly reduced the softening temperature. The softening temperature results of the briquettes also indicated that the boiler could be safely operated up to about 1100 0C with studied (Coal + Biomass) briquette.
The conclusion derived from present project work has been presented in Chapter 4 of this thesis.