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世界石膏资源丰富,世界石膏年产量保持在1亿t左右,如1998年1.07亿t,1999年达1.08亿t,然而近年来各国对副产品石膏的回收与利用也在加强。而且一些国家的副产品石膏产量也相当可观,如美国1998年的副产品石膏达460万t,仅在该国佛罗里达磷肥厂一处,副产品石膏的年产量有70万t之多;
The world’s gypsum resources are abundant. The annual output of gypsum in the world is maintained at about 100 million tons, such as 107 million tons in 1998 and 108 million tons in 1999. However, in recent years, the recovery and utilization of by-product gypsum have also been strengthened. Moreover, the gypsum production of by-products in some countries is also considerable. For example, in the US, the gypsum by-product of the United States reached 4.6 million tons in 1998, and only one place in the Florida Phosphate Fertilizer Plant has an annual output of 700,000 tons of gypsum.