Products steagips® Produktion FGD gypsum (desulfogypsum) is the end product of the desulfurization of flue gases from coal-fired power plants. The flue gases are processed in Flue Gas Desulfurization plants. steagips is solely produced in processes that use the principle of wet absorption. In this method an aqueous suspension of limestone or calcium oxide is injected into the flue gas stream. The sulfur dioxide contained in the flue gas is converted to calcium sulfite, which is then oxidized with air oxygene and thus transformed into calcium sulfate. The suspended calcium sulfate dihydate, commonly known as gypsum, is separated from the aqueous phase by mechanical processes and dehydrated down to a residual moisture of approx. 10%. steagips is available in humid, fine-grained form, or, after confection, in briquetted form. In Germany a total of approx. 2.2 million tonnes of FGD gypsum from coal-fired power plants was produced in 1999. Properties According to a study1) about the sanitary evaluation of natural and FGD gypsum, the differences between natural gypsum and FGD gypsum regarding the chemical composition and the content of trace elements are negligible from a sanitary point of view. The results of this study show that both FGD and natural gypsum can be used for the production of building material without sanitary concerns. The technological properties of FGD gypsum correspond to those of natural gypsum as well. FGD gypsum normally has a higher content of calcium sulfate dihydrate and a more uniform particle distribution than natural gypsum.2). The following table exemplarily shows a comparison between a natural gypsum and an FGD gypsum regarding their composition and some material properties. Parameter Unit Natural gypsum FGD gypsum Gypsum content % 95.3 98.2 pH value % 7.0 6.5 Norm color value % 83 77 Odor Neutral Neutral MgO % 0.02 0.02 Na2O % 0.01 0.02 K2O % 0.02 0.01 Chloride ppm 20 60 Calcium sulfite % 0 <0.01 Carbon components % 0 0.01 Aluminum oxide % 0.1 0.03 Iron (III) oxide % 0.1 0.03 Silicon dioxide % 1.2 0.2 Ca and Mg carbonate % 2.7 0.3 Bulk density g/dm³ 1020 1000 d50 µm 43 33 > 90 µm % 32.9 0.2 > 32 µm % 59.3 53.5 Comparison of natural gypsum and FGD gypsum2) The production of gypsum from flue gases from coal- fired power stations widely prevents the emission of sulfur dioxide and thus the development of acid rain and the resulting detrimental effects on the environment. The high quality of steagips allows a high-grade utilization in the building material industry and thus supersedes the landfilling of the original waste. By using steagips in the production of gypsum products, natural resources and landscapes are saved. Applications The FGD gypsum produced in Germany is utilized by 100%. In the building material industry it is used as a substitute for natural gypsum. The calcium sulfate dihydrate is used as a raw material for the production of beta and alpha hemihydrate. These intermediary products are used in the manufacturing of gypsum plasterboards, wallboards and fiber boards as well as plastering gypsum, and in the production of screed, mining mortar and other special products. Furthermore, FGD gypsum can be used as setting controller in cement production or as filler material in the production of varnish, adhesives, and plastics. 1) Beckert, J.; Einbrodt. H.J.; Fischer, M.: Vergleich von Naturgips und REA-Gips, Untersuchungen zur gesundheitlichen Beurteilung von Naturgips und REA-Gips aus Kohlekraftwerken im Hinblick auf deren Verwendung zur Herstellung von Baustoffen, VGB-Forschungsstiftung, Essen (Germany) and Bundesverband der Gips- und Gipsplattenindustrie e.V., Darmstadt (Germany), 1989. 2) Jurkowitsch, H.; Hüller, R.: Neue Gipskartonplatten unter Verwendung von Naturgips und verschiedenen synthetischen Gipsen, Zement-Kalk-Gips International, volume 43, 1990, issue 12, pages 583-588. steagips® is a registered trademark of STEAG Entsorgungs-GmbH
FGD gypsum (desulfogypsum) is the end product of the desulfurization of flue gases from coal-fired power plants. The flue gases are processed in Flue Gas Desulfurization plants.
steagips is solely produced in processes that use the principle of wet absorption. In this method an aqueous suspension of limestone or calcium oxide is injected into the flue gas stream. The sulfur dioxide contained in the flue gas is converted to calcium sulfite, which is then oxidized with air oxygene and thus transformed into calcium sulfate. The suspended calcium sulfate dihydate, commonly known as gypsum, is separated from the aqueous phase by mechanical processes and dehydrated down to a residual moisture of approx. 10%. steagips is available in humid, fine-grained form, or, after confection, in briquetted form. In Germany a total of approx. 2.2 million tonnes of FGD gypsum from coal-fired power plants was produced in 1999.
Properties According to a study1) about the sanitary evaluation of natural and FGD gypsum, the differences between natural gypsum and FGD gypsum regarding the chemical composition and the content of trace elements are negligible from a sanitary point of view. The results of this study show that both FGD and natural gypsum can be used for the production of building material without sanitary concerns.
The technological properties of FGD gypsum correspond to those of natural gypsum as well. FGD gypsum normally has a higher content of calcium sulfate dihydrate and a more uniform particle distribution than natural gypsum.2).
The following table exemplarily shows a comparison between a natural gypsum and an FGD gypsum regarding their composition and some material properties.
Parameter Unit Natural gypsum FGD gypsum Gypsum content % 95.3 98.2 pH value % 7.0 6.5 Norm color value % 83 77 Odor Neutral Neutral MgO % 0.02 0.02 Na2O % 0.01 0.02 K2O % 0.02 0.01 Chloride ppm 20 60 Calcium sulfite % 0 <0.01 Carbon components % 0 0.01 Aluminum oxide % 0.1 0.03 Iron (III) oxide % 0.1 0.03 Silicon dioxide % 1.2 0.2 Ca and Mg carbonate % 2.7 0.3 Bulk density g/dm³ 1020 1000 d50 µm 43 33 > 90 µm % 32.9 0.2 > 32 µm % 59.3 53.5 Comparison of natural gypsum and FGD gypsum2)
The production of gypsum from flue gases from coal- fired power stations widely prevents the emission of sulfur dioxide and thus the development of acid rain and the resulting detrimental effects on the environment.
The high quality of steagips allows a high-grade utilization in the building material industry and thus supersedes the landfilling of the original waste. By using steagips in the production of gypsum products, natural resources and landscapes are saved.
Applications
The FGD gypsum produced in Germany is utilized by 100%. In the building material industry it is used as a substitute for natural gypsum. The calcium sulfate dihydrate is used as a raw material for the production of beta and alpha hemihydrate. These intermediary products are used in the manufacturing of gypsum plasterboards, wallboards and fiber boards as well as plastering gypsum, and in the production of screed, mining mortar and other special products. Furthermore, FGD gypsum can be used as setting controller in cement production or as filler material in the production of varnish, adhesives, and plastics.
1) Beckert, J.; Einbrodt. H.J.; Fischer, M.: Vergleich von Naturgips und REA-Gips, Untersuchungen zur gesundheitlichen Beurteilung von Naturgips und REA-Gips aus Kohlekraftwerken im Hinblick auf deren Verwendung zur Herstellung von Baustoffen, VGB-Forschungsstiftung, Essen (Germany) and Bundesverband der Gips- und Gipsplattenindustrie e.V., Darmstadt (Germany), 1989.
2) Jurkowitsch, H.; Hüller, R.: Neue Gipskartonplatten unter Verwendung von Naturgips und verschiedenen synthetischen Gipsen, Zement-Kalk-Gips International, volume 43, 1990, issue 12, pages 583-588.
steagips® is a registered trademark of STEAG Entsorgungs-GmbH