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美国磷矿开采方式以露天为主,地下开采所占比重很小,且仅限于西部磷矿区。同其它采矿工业比较发达的国家一样,美国磷矿开采也经历了生产规模从小到大、工艺设备由土到洋的过程。根据工艺设备的演变情况,在时间上也大致可分三个发展阶段: 第一阶段包括1891年以前历年,为土法开采时期。生产矿山规模一般都很小,工艺和机具简单而粗糙,无论是在当时的南卡罗来纳、佛罗里达及其它州,均主要靠手工作业,用镐、铲、手推车及畜力运输进行小生产,采矿工效普遍很低,10～20人每小时才生产1吨矿,原
The exploitation of phosphate rock in the United States is dominated by the open air. The proportion of underground mining is small and limited to the western phosphate rock area. Like other mining industries in developed countries, the United States also experienced the development of phosphate mining production scale from small to large, process equipment from soil to ocean process. According to the evolution of process equipment, it can be roughly divided into three stages of development in time: the first stage includes the calendar year before 1891, which is the mining period of indigenous law. The mines were generally small in size and simple and rough in craftsmanship and machinery. Both South Carolina, Florida and other states at the time were mainly handcrafted, with small picks, shovels, trolleys and animal transport for small-scale production, and mining efficiency was widespread Very low, 10 to 20 people only produce 1 ton of ore per hour, the original