Full-Scale Industrial Application of Adipic Acid Enhanced Limestone Utilization in Wet Flue Gas Desulfurization Systems
Source abstract
Abstract
Wet flue gas desulfurization (WFGD) is a widely used process for controlling SO2 emissions in coal-fired power plants. However, the slow dissolution kinetics of limestone (CaCO3) and the poor dewatering properties of gypsum crystals significantly limit the performance of this process. In this study, the effects of adding adipic acid, an organic acid, at different concentrations (0, 500, 1000, and 1500 ppm) to limestone slurry in the WFGD process were investigated. SO2 removal performance, limestone consumption, and gypsum quality were evaluated. SO2 removal efficiency remained unaffected by the addition of adipic acid. The addition of adipic acid reduced limestone consumption by 6.89%, 8.35%, and 9.92% in WFGD, respectively. The moisture content of gypsum decreased from 22.4% to 9.2%. The results revealed that adipic acid accelerates limestone dissolution via a ligand-assisted proton-transfer mechanism and improves the overall efficiency of the WFGD process by controlling gypsum crystallization. The physical quality and structure of gypsum obtained from the WFGD were evaluated by Scanning Electron Microscopy (SEM). Adipic acid led to the development of larger, smoother, and potato-like morphologies in the gypsum crystals and improved dewatering performance. This study demonstrates that using adipic acid in WFGD processes is a significant improvement strategy that enhances process efficiency by accelerating limestone dissolution and controlling gypsum crystallization. Adipic acid addition is an effective optimization strategy for full-scale industrial WFGD systems.
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Research context
OpenAlex topics: Industrial Gas Emission Control · Chemical Looping and Thermochemical Processes · Carbon Dioxide Capture Technologies
SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.
Affiliations
Department of Energy Systems Engineering, Faculty of Engineering and Natural Sciences, Iskenderun Technical University, 31200 Hatay, Türkiye
Department of Biomedical Engineering, Faculty of Engineering and Natural Science, Iskenderun Technical University, 31200 Hatay, Türkiye
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