Exergy analysis of the flue gas pre-dried lignite-fired power system based on the boiler with open pulverizing system

Xiaoqu Han, Ming Liu, Kaili Wu, Weixiong Chen, Feng Xiao and Junjie Yan

Energy, 2016, vol. 106, issue C, 285-300

Abstract: This paper deals with an exergetic analysis of the flue gas pre-dried lignite-fired power system (FPLPS) based on the boiler with open pulverizing system (OPSB) to explore the energy-saving potential of the FPLPS. A steady-state simulation was performed to obtain thermodynamic properties of process streams in a 600 MW unit. Results indicated that the plant efficiency of the FPLPS was relatively 3.42% higher than that of the conventional lignite-fired power system (CLPS). The improvement benefited from the integration of the flue gas dryer with the OPS, in which the dryer exhaust gas was separated from coal powders and prevented from recycling in the furnace. Consequently, the exergy destruction in the combustion process was reduced by 2.32%-pts for increased flame temperature, and the exergy loss of the boiler exhaust gas was reduced by 0.68%-pts for decreased temperature. Moreover, the dryer exergy efficiency was only 20.20% due to considerable exergy destructions in the moisture evaporation and the mixing of drying agents. The proposed retrofitting option by extracting cold flue gas from the economizer outlet could increase the plant efficiency by 0.33% relatively. Finally, attempts were made to examine the influence of varying pre-drying parameters on system performances.

Keywords: Exergy analysis; Flue gas pre-drying; Lignite; Open pulverizing system; Simulation (search for similar items in EconPapers)
Date: 2016
References: View references in EconPapers View complete reference list from CitEc
Citations: View citations in EconPapers (12)

Downloads: (external link)
http://www.sciencedirect.com/science/article/pii/S0360544216302912
Full text for ScienceDirect subscribers only

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:eee:energy:v:106:y:2016:i:c:p:285-300

DOI: 10.1016/j.energy.2016.03.047

Access Statistics for this article

Energy is currently edited by Henrik Lund and Mark J. Kaiser

More articles in Energy from Elsevier
Bibliographic data for series maintained by Catherine Liu ().