一、可观的数字:每年美国可回收4000万吨废黑色金属,300万吨废有色金属。1984年,从废料再生的金属和矿物原料价值为40亿美元。据估计,美国汽车制造业所用的铬仅回收30～40%。根据技术评议处的报告,仅从汽车的催化转换器中即可回收铬5000～7000吨。1982年美国从汽车催化剂中回收了约115000盎司的铂族金属,估计到1995年可回收50万盎司的铂族金属。 First, a considerable figure: the United States annually recyclable 40 million tons of waste black metal, 300 tons of waste non-ferrous metals. In 1984, the value of the metal and mineral raw materials recovered from scrap was 4 billion U.S. dollars. It is estimated that only 30-40% of the chromium used in the U.S. auto industry is recovered. According to a report from the Technology Review Office, 5000 to 7,000 tons of chromium can be recovered from the catalytic converter of a car alone. In 1982, the United States recovered approximately 115,000 ounces of platinum group metals from automotive catalysts and estimated that 500,000 ounces of platinum group metals could be recovered by 1995.