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Method for preparing anhydrous calcium sulfate powder from phosphogypsum
The invention provides a method for preparing anhydrous calcium sulfate powder from ardealite, and belongs to the technical field of inorganic fillers. The preparation method comprises the following steps: mixing a chelating antioxidant and phosphogypsum to obtain a pre-crystal transformation material; and calcining the pre-crystal transformation material to obtain the anhydrous calcium sulfate powder. According to the invention, after the ardealite and the chelating antioxidant are fully mixed, in the calcining process, along with the temperature rise, moisture and impurities (including organic matters, HF, free sulfuric acid, phosphorus, metals and the like) contained in the ardealite are continuously evaporated, decomposed and converted under the action of high temperature, volatile substances are discharged in a gas state, and phosphorus is converted into inert pyrophosphate; the chelated antioxidant generates a complex with the readily oxidizable substance (ions) at high temperature to prevent the readily oxidizable substance from being oxidized, meanwhile, free radicals are decomposed to be combined with oxygen to form peroxy free radicals, oxygen is consumed, the contact probability of the readily oxidizable substance and the oxygen is reduced, and the calcined anhydrous calcium sulfate powder does not have red and yellow phenomena any more.
本发明提供了一种磷石膏制备无水硫酸钙粉体的方法，属于无机填料技术领域。本发明将螯合抗氧剂和磷石膏混合，得到预转晶料；将预转晶料煅烧，得到无水硫酸钙粉体。本发明中，磷石膏与螯合抗氧剂充分混合后，在煅烧过程中，随着温度升高，磷石膏中水分和含有的杂质(包括有机物、HF、游离硫酸、磷、金属等)在高温作用下不断蒸发、分解、转化，易挥发物质以气态方式排出、磷转化为惰性的焦磷酸盐；螯合抗氧剂在高温下与易氧化物(离子)生成络合物阻止其被氧化，同时分解出自由基与氧气结合形成过氧自由基，消耗氧气，降低了易氧化物与氧气接触几率，使得煅烧出的无水硫酸钙粉体不再有泛红、泛黄的现象。
Method for preparing anhydrous calcium sulfate powder from phosphogypsum
The invention provides a method for preparing anhydrous calcium sulfate powder from ardealite, and belongs to the technical field of inorganic fillers. The preparation method comprises the following steps: mixing a chelating antioxidant and phosphogypsum to obtain a pre-crystal transformation material; and calcining the pre-crystal transformation material to obtain the anhydrous calcium sulfate powder. According to the invention, after the ardealite and the chelating antioxidant are fully mixed, in the calcining process, along with the temperature rise, moisture and impurities (including organic matters, HF, free sulfuric acid, phosphorus, metals and the like) contained in the ardealite are continuously evaporated, decomposed and converted under the action of high temperature, volatile substances are discharged in a gas state, and phosphorus is converted into inert pyrophosphate; the chelated antioxidant generates a complex with the readily oxidizable substance (ions) at high temperature to prevent the readily oxidizable substance from being oxidized, meanwhile, free radicals are decomposed to be combined with oxygen to form peroxy free radicals, oxygen is consumed, the contact probability of the readily oxidizable substance and the oxygen is reduced, and the calcined anhydrous calcium sulfate powder does not have red and yellow phenomena any more.
本发明提供了一种磷石膏制备无水硫酸钙粉体的方法，属于无机填料技术领域。本发明将螯合抗氧剂和磷石膏混合，得到预转晶料；将预转晶料煅烧，得到无水硫酸钙粉体。本发明中，磷石膏与螯合抗氧剂充分混合后，在煅烧过程中，随着温度升高，磷石膏中水分和含有的杂质(包括有机物、HF、游离硫酸、磷、金属等)在高温作用下不断蒸发、分解、转化，易挥发物质以气态方式排出、磷转化为惰性的焦磷酸盐；螯合抗氧剂在高温下与易氧化物(离子)生成络合物阻止其被氧化，同时分解出自由基与氧气结合形成过氧自由基，消耗氧气，降低了易氧化物与氧气接触几率，使得煅烧出的无水硫酸钙粉体不再有泛红、泛黄的现象。
Method for preparing anhydrous calcium sulfate powder from phosphogypsum
一种磷石膏制备无水硫酸钙粉体的方法
ZHU TONGRAN (author) / ZHANG YANSHUN (author) / HUANG YALING (author) / YANG WEIXIAN (author)
2024-01-23
Patent
Electronic Resource
Chinese
IPC:
C04B
Kalk
,
LIME
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