Exergetic, Thermal, and Fuel Savings Analyses of a Heat-matched, Bagasse-based Cogeneration Plant in Sugar Industries
DOI:
https://doi.org/10.13052/dgaej2156-3306.2413Keywords:
Bagasse, cogeneration, exergy, efficiency.Abstract
The sugar industry employs different cogeneration schemes to sat-
isfy process steam demand, and generates surplus power by upgrading
the steam inlet parameters. A wide range of steam inlet parameters is
used in Indian sugar industries, and varies from 21 bar to 110 bar in
pressure and 330°C to 540°C in temperature. Most of the people under-
stand that higher pressure (HP) steam inlet conditions result in more
efficient power plant. In this article, exergy methods, in addition to
more conventional energy analysis, are employed to evaluate overall and
component efficiencies and to identify and assess thermodynamic losses.
The analysis is carried out for a heat-matched bagasse-based cogenera-
tion plant of a typical 2500 tcd sugar factory using a backpressure steam
turbine and an extraction condensing steam turbine for a wide range
of steam inlet conditions; selected around the sugar industry’s export
cogeneration plant for better choice of cogeneration plant configura-
tion. The results indicate that a backpressure turbine plant achieves the
highest energy and exergetic efficiency, and fuel savings; the condensing
turbine plant generates maximum power per tonne of cane processed.
Steam inlet conditions of 61 bar and 475°C can be considered as the
optimal steam parameters that yield the best thermodynamic advantage.
Exergy analysis of the components indicates that the turbine is the most
efficient and the boiler is the least efficient component of the plant.
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