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1994年美国稀土产量提高。美国稀土主要是加利福尼亚州和佛罗里达州的矿山生产的。稀土主要还是用于冶金应用和石油裂化催化剂。美国氟碳酸铈镧矿精矿产量增加,但独居石精矿产量减少。精加工稀土消耗量增加,但独居石精矿产量减少。精加工稀土消耗量增加,因为美国经济从1993年开始复苏。美国仍然是稀土主要进口国和出口国。佛罗里达州独居石中含有钇,加利福尼亚州氟碳酸铈镧矿中含有少量钇。美国不生产精加工钇。美国所需的大部分钇仍从中国进口。美国不开采钪。国内有3家处理厂精加工钪矿石和精矿。世界钪矿石生产主要是在中国和俄罗斯。镧系矿石和钇矿石主要生产国是澳大利亚、巴西、中国、印度以及俄罗斯。美国从国外进口氟碳酸铈镧矿、钛铌酸钠铈矿、独居石以及粘土形式的稀土。稀土矿的主要处理国是
In 1994 the United States increased rare earth production. American rare earths are mainly produced in mines in California and Florida. Rare earth is mainly used for metallurgical applications and petroleum cracking catalysts. US bastnaesite concentrate production increased, but monazite concentrate production decreased. Finishing rare earth consumption increased, but the production of monazite concentrate decreased. Finishing rare earth consumption increased because the U.S. economy started to recover from 1993. The United States is still a major importer and exporter of rare earths. Yttrium is contained in monazite in Florida and a small amount of yttrium is contained in cesium lanthanum mine in California. The United States does not produce finished yttrium. Most of the yttrium needed by the United States is still imported from China. The United States does not mine scandium. There are three domestic processing plant finishing scandium ore and concentrate. World production of scandium ore is mainly in China and Russia. Lanthanum ore and yttrium ore are the main producing countries of Australia, Brazil, China, India and Russia. The United States imported rare earths from abroad, including bastnasite, cericotitanium niobate, monazite and clay. The main processing country of rare earth ore is