Economic performance assessment of elemental sulfur recovery with carbonate melt desulfurization process
Juwon Lee, Yuchan Ahn, Hyungtae Cho, Junghwan Kim
Abstract
This study develops an elemental sulfur recovery (ESR) process from sulfur dioxide (SO2) as a hazardous material removed from flue gas emitted at thermal coal-fired power plants with a carbonate melt flue gas desulfurization (CMFGD) process. The carbonyl sulfide (COS) generated as a byproduct after removing SO2 from flue gas using carbonate melt in the CMFDG is utilized as a resource to produce elemental sulfur by applying the hydrolysis and Claus processes in the ESR process. In addition, to increase energy independence in the integrated CMFGD-ESR process, heat integration was applied by introducing new heat exchanger networks that utilize the waste heat in the proposed process. The levelized cost of the integrated CMFGD-ESR process was determined to be US$ 811 per ton SO2 removed; from this result, the proposed process to remove hazardous material from flue gas emitted at thermal coal-fired power plants is economically benign compared to conventional SO2 removal processes (US$ 500 ~ US$ 1200 per ton SO2 removed), which use limestone as the raw material.