Analysis of Flow Characteristics of Slurry Transportation System

Abstract

Coal is a major source of energy. In India, about 70% electricity generation is produced by combustion of pulverized coal in thermal power plants. The major challenge throughout the world is the efficient utilization of a fuel in power generation. The concentrated coal-water slurry contains 60 70% coal powder that is used as a liquid fuel for the replacement of oil as a fuel. The maximum concentration of slurry with appreciable viscosity increases the efficiency of transportation of the coal-water slurry in pipelines for fuel generation. Combustion of coal in power plants generates a huge quantity of inorganic residues like bottom ash and fly ash, which have numerous ecological problems. Generally the coal ash is being transported hydraulically to ash pond through slurry pipelines at low solid concentrations, which is extremely uneconomical. The efficient and economical transportation of coal water slurry as well as coal ash slurry is a major challenge. The parameters, which have significant effect on the slurry transportation system, are slurry concentrations and slurry rheology. The economy of slurry transportation is achieved by transporting higher concentration of slurry having minimum viscosity so that the power required for transportation will be minimum. So the understanding of impact of these parameters on slurry transportation is necessary for efficient designing of slurry transportation system. The present study is concerned with the analysis of impact of slurry rheology and slurry concentration on slurry transportation in a pipeline. The coal samples are collected directly from the coalmines of Makum coalfield of Dibrugarh district of Assam for the present study. The coal samples are prepared by crushing with laboratory-size ball mill to the different fractional sizes required for experiments. The Makum field coal is also used for power generation in Guru Nanak Dev thermal power plant, Bathinda, Punjab, India.