Economic Analysis of Wet Flue Gas Desulfurization System with the Application of Low Pressure Economizer for Waste Heat Recovery

Abstract:

The data of wet flue gas desulfurization (WFGD) power and water consumption, from two different coal-fired power plants (100 MW and 1000 MW) under full load operation, are studied for the WFGD economic analysis of waste-heat-recovery transformation with the installation of low pressure economizer (LPE). The results of 100MW unit show that, WFGD inlet flue gas temperature drops from 155°C to 110°C, the benefits generated include power consumption of fans declines by 23.85% and water consumption of the smoke desulfurization absorption tower declines by 34.88%. In another case, the temperature of inlet flue gas from WFGD of 1000 MW unit drops from 130°C to 84°C, power consumption of fans increases by 15.04% while water consumption of the smoke desulfurization absorption tower declines by 73.1%. Besides, the flow resistance is increased in LPE water side due to the installation of LPE. This makes power consumption of condensate pump enhanced, which slightly decreases the benefits from waste heat recovery.

• Periodical: Advanced Materials Research (Volumes 1092-1093)
• Pages: 491-497
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.1092-1093.491
• Online since: March 2015
• Authors: Jing Hui Song, Yan Lin, Yan Fen Liao*, Xiao Qian Ma, Shu Mei Wu
• Keywords: Waste Heat Recovery, Water Consumption Reduction, Wet Flue Gas Desulfurization

References

[1] Wang CJ, He BS, Sun SY, Wu Y, Yan N, Yan LB, et al. Application of a low pressure economizer for waste heat recovery from the exhaust flue gas in a 600 MW power plant. Energy 2012; 48: 196-202.

DOI: 10.1016/j.energy.2012.01.045

[2] Chaojun Wang, Boshu He, Linbo Yan, Xiaohu Pei, Shinan Chen. Thermodynamic analysis of a low pressure economizer based waste heat recovery system for a coal-fired power plant. Energy 2014; 65: 80-90.

DOI: 10.1016/j.energy.2013.11.084

[3] Nolan P S, Redinger K E. Demonstration of additive use for enhanced mercury emissions control in wet FGD systems. Fuel Process Technology, 2004 (85): 587-600.

DOI: 10.1016/j.fuproc.2003.11.009

[4] CHEN Haizhan, YUAN Xing, XU gang. Modeling and Analysis on the Water Consumption of the Wet Flue Gas Desulphurization System in Thermal Power Plants. Modern Electric Power Vol. 28 No. 5 (2011), p.68.

[5] ZHU Wen-bin, WANG Ding. Analysis and correction of outlet gas temperature and evaporation of water of desulfurization tower in WFGD. Boiler Technology Vol. 38 No. 4 (2007), p.68.

[6] XUE Dianhua. Air Conditioning, Tsinghua University Press, (2008).