Wang Haoqian, Wang Feifei, Qin Weiran, He Chiquan, Wang Fushun, Liang Xia, Li Xiaoping
School of Environmental and Chemical Engineering, Shanghai University, Shanghai 200444, China.
School of Environmental and Chemical Engineering, Shanghai University, Shanghai 200444, China.
Sci Total Environ. 2024 Oct 1;945:174053. doi: 10.1016/j.scitotenv.2024.174053. Epub 2024 Jun 17.
Flue gas desulfurization gypsum (FGDG), a solid waste produced during sulfur removal in coal-fired power plants, has applications in saline-alkali soil amelioration due to its function of calcium‑sodium ion exchange. Existing research has focused on the use of gypsum to improve saline-alkali soils in non-coastal areas. However, coastal areas are not only extensively salinized, but an important source of methane, and surprisingly, FGDG may assist to decrease methane formation mainly by the action of sulfate radical. This is the first critical review to systematically discuss the effects of FGDG on both saline-alkali soil improvement and carbon emission control in tidal flats, including application status, amendment principles, environmental risks and methane emission control. After adding FGDG, soil salinization degree was weakened via adjusting soil structure, pH, exchangeable sodium percentage and electric conductivity, introduction of nutrients also promotes crop growth. The optimal FGDG dosage in tidal flats seems to be higher (>2 %) than that in non-coastal areas (<1 %). Its environmental risks regarding heavy metals and eutrophication are evaluated safe. In tidal areas, more methane is produced in hot seasons and ebb tides. Plants and invertebrates also promote methane release. FGDG controls methane production by promoting the activity of sulfate-reducing bacteria and inhibiting methanogens. Considering methane flux levels and seawater erosion, FGDG use in low tidal beach needs more research, while that in high and middle tidal beach is recommended. This review will expand applications and appropriate use of FGDG for reducing carbon emission and improving ecological services in coastal areas.
烟气脱硫石膏（FGDG）是燃煤电厂脱硫过程中产生的一种固体废弃物，由于其钙钠离子交换功能，在盐碱地改良中具有应用价值。现有研究主要集中在利用石膏改良非沿海地区的盐碱地。然而，沿海地区不仅盐碱化程度高，而且是甲烷的重要来源，令人惊讶的是，FGDG可能主要通过硫酸根自由基的作用有助于减少甲烷生成。这是第一篇系统讨论FGDG对潮滩盐碱地改良和碳排放控制影响的综述，包括应用现状、改良原理、环境风险和甲烷排放控制。添加FGDG后，通过调整土壤结构、pH值、交换性钠百分比和电导率来减弱土壤盐碱化程度，引入养分也促进作物生长。潮滩中FGDG的最佳用量似乎高于非沿海地区（>2%）（<1%）。其在重金属和富营养化方面的环境风险被评估为安全。在潮汐区域，炎热季节和落潮时会产生更多甲烷。植物和无脊椎动物也会促进甲烷释放。FGDG通过促进硫酸盐还原菌的活性和抑制产甲烷菌来控制甲烷生成。考虑到甲烷通量水平和海水侵蚀，FGDG在低潮滩的应用需要更多研究，而在中高潮滩则建议使用。本综述将扩大FGDG在沿海地区减少碳排放和改善生态服务方面的应用及合理使用。
