Title: Exergy and sustainability analysis of quintuple effect evaporation unit in a sugar industry - a case study
Authors: S.M. Bapat; V.S. Majali; G. Ravindranath
Addresses: Department of Mechanical Engineering, Gogte Institute of Technology, Belgaum, 590008, India ' Department of Mechanical Engineering, Gogte Institute of Technology, Belgaum, 590008, India ' APS College of Engineering, Bangalore, 560082, India
Abstract: The present work evaluates the performance of quintuple effect evaporation unit by using exergy analysis based on actual operating/experimental data. Process steam for first evaporator is used as heating media, and the cane juice is concentrated from 14 brix to 70 brix. Exergy analysis reveals that first evaporator is the least efficient component with a value of 74.66%, whereas third evaporator is the most efficient component with a value of 93.40%. Further, the analysis shows the magnitude, locations and causes for inefficiencies. A new modified evaporation system is proposed with certain suggestions and improvements, which minimises the magnitude of these losses. Analysis of the proposed new system shows it to be more sustainable (in terms of exergy) as compared to the existing evaporation system. The average exergy efficiency improved to a value of 91.88% whereas sustainability index improved from a value of 3.451 to 4.452. It is expected that the present analysis would play a significant role in evaluating and increasing the use of sustainable energy and technologies in sugar industry.
Keywords: exergy analysis; quintuple effect evaporation; sugar industry; evaporator; process steam; sustainability; sustainable development; case study; cane juice; exergy efficiency.
International Journal of Renewable Energy Technology, 2016 Vol.7 No.1, pp.46 - 68
Received: 23 Nov 2014
Accepted: 09 Apr 2015
Published online: 01 Dec 2015 *