In the end of an era in US lead operations, Doe Run Company finally shut down all primary lead operations at its Herculaneum, Missouri location as of December 23, 2013. This was the last primary lead smelter operating in the US. Doe Run’s Missouri lead mines and mills continue to operate, producing high quality lead concentrate. Lead is a key component of batteries used for transportation and backup power in a variety of industries, including technology, communications and renewable energy.
Approximately 98% of lead-acid batteries are recycled, turning the used metals and other components into new products. More than 13 million of these batteries are recycled annually at Doe Run’s lead recycling centre in southern Missouri, one of the world’s largest. The Doe Run smelter had been supplying 8 to 10% of US demand for lead through its Herculaneum smelter. Some 75 employees will be retained in 2014 to assist with continued refining and alloying, and the maintenance of our site.
Leading up to the closure, Gary Hughes, General Manager of Doe Run’s Metals Division said: “Our final production days will be our best. We intend to meet our customers’ needs in a safe and responsible manner. We will receive the final shipment of lead concentrates from our Missouri mines in the next several days, producing one of the highest grades of primary lead metal in the world in the final weeks of December. Although we will continue to mine and mill lead, zinc, and copper from our underground mines, the ability to produce primary lead metal and their alloys domestically will vanish.”
In 2010, Doe Run reached a comprehensive settlement with the US Environmental Protection Agency and the State of Missouri. As part of that settlement, Doe Run agreed to discontinue its smelting operations in Herculaneum by the end of 2013. “We saw no alternative to closing our plant,” stated Hughes. “We are aware of no primary lead smelting process that will meet the standard for ambient air at the Herculaneum site. We believe the only existing technology that can meet today’s standards in Herculaneum, as well as potential future standards, is the new electrowinning lead metal process we announced in 2010. We hoped to be building such a plant by now, however, constructing a full-scale plant given other regulatory compliance spending requirements puts our company at financial risk. We may pursue a smaller scale plant if conditions become more favorable.”
The US ambient air quality standard for lead emissions is the most restrictive in the world. In 2008, the National Ambient Air Quality Standard for lead was reduced from 1.5 µg/m3 (micrograms of lead per cubic metre of air) to 0.15 µg/m3. Doe Run had hoped to bring the revolutionary lead metal production technology online prior to the closure of the smelter. This proprietary, new technology uses a wet-chemical, electrowinning process instead of a heat-based smelting process, greatly reducing sulfur dioxide and lead emissions. In 2012, the company announced that costs to build an electrowinning plant similar in production size to the smelter were too great for the company given the present economic conditions and other demands on operations.