Copper Area News
Plans for a $110 million upgrade of the Hayden copper smelter that will bring the apparatus in compliance with new federal regulations concerning emissions of sulfur dioxide (SO2) have been filed by owner ASARCO/Grupo Mexico with the Arizona Department of Environmental Quality (ADEQ).
The rules issued by the US Environmental Protection Agency (EPA) require that SO2 emissions from the smelter be reduced from 140 ppb (parts per billion) to 75 ppd during a 24-hour period. The Hayden smelter has until Oct. 3, 2018 to meet this standard.
Meeting the standard is important to keep the Hayden copper smelting plant operating and providing employment for residents of the Hayden/Winkleman area.
To meet EPA’s goal, the plan ASARCO filed on June 24 with ADEQ describes a converter retrofit project that will replace the smelter’s five current 13-ft. diameter converters with three 15-ft. diameter converters. Also included in the plan are the installation of improved primary and secondary hoods, and an electrostatic precipitator for solids removal prior to SO2 recapture at the smelter’s existing acid plants. Larger ladles (300 cu. ft. instead of 200 cu. ft.) will be installed to reduce the number of hot metal transfers. Additional upgrades will capture secondary gases and direct them to the acid plant for conversion to a sulfuric acid product.
Overall the plan aims to reduce SO2 emissions at the Hayden smelter by 85 percent, with a total SO2 capture rate of 99.7 percent of what is produced during the copper smelting process.
The plans were made public during a meeting of the Arizona House Committee on Energy, Environment and Natural Resources held Aug. 22 at the Gila Community College Pueblo Campus in Globe.
ADEQ is expected to rule on the ARARCO plan by late September. If approved the plan will then go to EPA for an additional 45-day comment period. With EPA approval, ASARCO could begin work on the upgrades before year’s end.
Work on the converter retrofit will be performed as to not disrupt the operation of the smelter and keep all employees working their regular daily schedules, said Krishna Parameswaran, director of environmental services and compliance assurances at ASARCO. The smelting plant must operate within the EPA emission limits by Oct. 3, 2018.
The smelter and surrounding operations are an important parts of the Hayden economy. It employs 1,400 hourly and salaried workers, who are annually paid $140.8 million in wages, salaries and fringe benefits. The operations also generate $28.6 million in property, severance and sales taxes. The company annually generates spending of $345.8 million on materials, fuel and supplies into the Arizona economy.
Each year the Hayden smelter produces more than 300 million tons of copper that is important in all electrical products, electronic equipment, and even bringing electricity to homes, according to Kelly Norton, president of the Arizona Mining Association. The smelter also products more than 575,000 short tons of sulfuric acid each year.
Although originally built in 1912, the Hayden smelter has been expanded and upgraded on a regular basis, with the last major renovations taking place in 1989 and 1996. In 2012, ASARCO voluntarily undertook a $10 million project to reduce lead emissions through the addition of a monitor system to keep lead emissions to within EPA rules issued in 2008 that trimmed allowable emission levels to one-tenth of the former standard.
The EPA-required Hayden smelter renovation projects comes only a step behind a more expensive project for the smelter in Miami owned by Freeport-McMoRan. Budgeted at $450 million, the Miami smelter will receive new converter mouth covers, converter aisle canopy hoods and aisle scrubbers, an anode plant bag house and a smelter furnace upgrade to meet EPA SO2 emission limits.
Freeport-McMoRan received its permit on July 21 and has begun renovation work that could be completed by the end of 2017. The Miami smelter, which was originally built in 1915, also has undergone numerous upgrades, expansions and renovations in the interim.
Norton emphasized at the meeting that copper smelting is an important contributor to the Arizona economy. At present there are only three copper smelting plants in the US and two are in Arizona (Hayden and Miami). The third is in Salt Lake County, UT, Norton noted.