A coalition of environmental groups filed suit against the EPA on September 3, 2024, challenging the Agency’s final emissions rule for coke ovens and coke oven batteries.
The coalition includes the Greater-Birmingham Alliance to Stop Pollution (GASP), the Clean Air Council, the Hoosier Environmental Council, Just Transition Northwest Indiana, PANIC, PennFuture, and the Sierra Club and is represented by Earthjustice.
The suit, GASP et. al. v. EPA, was filed in the D.C. Circuit Court of Appeals and asks the court to review the EPA’s final rule, titled “National Emission Standards for Hazardous Air Pollutants for Coke Ovens: Pushing, Quenching, and Battery Stacks, and Coke Oven Batteries; Residual Risk and Technology Review, and Periodic Technology Review.”
“In Western Pennsylvania, Northern Indiana, Alabama, and other locations throughout the U.S., coke oven plants superheat coal in a kiln. The process releases toxic chemicals like benzene, mercury, lead, and arsenic into the air. On July 5, the EPA failed communities finalizing a rule that does not reduce the toxic air pollution coke ovens emit,” states an Earthjustice press release. “Earthjustice clients filed a lawsuit challenging the new rule … because the EPA must protect nearby communities by controlling the release of toxic air pollution from coke ovens.”
The EPA defines a coke oven as a chamber of brick or other heat-resistant material in which coal is heated to separate the coal gas, coal water, and tar. The coal gas and coal water fuse together with carbon and the remaining ash, forming a hard residue commonly referred to as coke, which is primarily used in steel production.
The process
Coke is produced from coal because coal can’t be placed directly into a blast furnace because of the harmful byproducts.
Within a coke oven, coal is heated to approximately 1,250 degrees Celsius. This step in the process is called “dry distillation” because there’s no oxygen in the oven and the coal doesn’t truly burn, according to GASP. It takes about 18 hours to convert 35 tons of coal into 25 tons of coke.
Coke oven batteries are a set of coke ovens with common walls. These contain 10 to 100 ovens that are usually 20 feet tall, 40 feet long, and less than 2 feet wide, notes Kallanish Commodities.
“After heating up the coal into coke, the coke is then unloaded from the oven by a pusher machine. The pusher machine has a pusher arm that puts the coke into a car that takes the coke to a coke quenching tower. Here, the coke is quenched with water. The coke is then taken to a coke wharf, where the remaining water evaporates. A reclaimer then feeds the coke from the wharf to a conveyor belt, which transfers the coke to the crushing and screening station. The finished product is about two-thirds the weight of the original raw material,” GASP explains. “During the distillation process, a large amount of gas and smoke is generated, which, after purification, creates coke oven gas, and other by-products such as ammonia, tar, sulfur, naphthalene and benzol. The creation of coke and the purification of gas are … completely automated.”
Not all coal is useful for the steel-making process. Coal used to produce steel is called metallurgical (met) coal, which has “low sulfur content (<1%), low ash yield (<7%), low volatile matter (15 to 40%) and low phosphorous, low chlorine, and low alkali content,” notes the University of Kentucky. “Both the coals and subsequent cokes are tested for their quality. Another important quality of the coke, which is tested, is its strength. Coals and cokes are also microscopically analyzed (called petrography) to determine the relative proportions of ‘reactive’ components (vitrinite and liptinite macerals) vs. ‘inert’ components (inertinite macerals and mineral matter), which influence coking properties.”
The moisture content and density of the coal used impact the coke produced. The coke-making process produces carbon monoxide and other volatile emissions.
“Pollution prevention in coke making is focused on reducing emissions from the coke oven,” GASP says. “There are many ways to help reduce pollution. One way is to improve the quality of coal feed, so that the coke produced is of higher quality. This helps reduce emissions of sulfur oxide and other pollutants. Another way is to use enclosed conveyors for the coal and coke handling. Using higher quality coal helps reduce the time it takes to convert it into coke, it also helps reduce fuel consumption.”
Additionally, using several windbreaks and reducing the drop distances reduce pollution.
Final rule
According to an EPA fact sheet, the final amendments to the rule will establish:
- More protective standards for hazardous air pollutant (HAP) leaks from doors and other sources at coke oven batteries;
- A fenceline monitoring requirement to ensure coke oven batteries regularly monitor benzene levels near the facility and take appropriate corrective action if these levels exceed a particular threshold;
- Opacity limits for bypass and waste heat stacks; and
- Standards for currently unregulated pollutants, such as mercury and non-mercury metals, emitted by coke ovens.
The EPA reports there are 11 active coke oven plants remaining in the United States.
The environmental groups filed suit because they don’t believe the new regulations contain strong enough emissions limits for benzene.
“For three decades, EPA has failed to protect people from coke ovens, which the agency itself says emit ‘among the most toxic of all air pollutants.’ This rule continues that same trend of indifference to people living near coke ovens, as EPA: eliminated fenceline monitoring from half the source category; never reviewed the health risks posed by leaking ovens; overlooked viable pollution control strategies—like variable pressure regulation or creating a 1-hour standard—that the agency’s own staff advocated for,” said Earthjustice Senior Attorney Tosh Sagar in an e-mail.
Communities in Pennsylvania, Alabama, Indiana, Michigan, and Ohio have suffered enough, Sagar said, according to the Environmental Integrity Project (EIP).
“We’re urging the D.C. Circuit to force the EPA to finally do its job and protect them.”
According to EIP Attorney Haley Lewis, the “EPA failed to impose strong enough standards to adequately protect the public and failed to require industry to install modern pollution control technologies that are readily available.”
Cleaner steel
Cleaner production methods reduce pollution. Steel is one of the materials the EPA sees as having “significant opportunities” to be produced in a more sustainable manner.
The EPA’s recently announced label program to bolster the production of cleaner, more climate-friendly construction materials provides industry the opportunity to distinguish itself by moving to processes that result in a lower carbon footprint.
Eco-friendly practices for steel production, according to steel products and services provider Top End Steel, include:
- More efficient production methods
Replacing traditional blast furnaces with electric arc furnaces (EAFs) is more energy-efficient and primarily uses recycled steel scrap to manufacture new steel. Continuous casting processes can also be used to reduce environmental impacts.
- Alternative low-carbon materials
Biomass is an alternative material that’s gaining traction and is used as a substitute for coal in the iron reduction process. Derived from plant materials, biomass is carbon neutral, meaning it absorbs as much carbon as it emits.
“The development of new alloys that require less energy-intensive processing and lower temperatures during production is rising,” Top End Steel notes. “These materials help reduce the carbon emissions associated with steel production and enhance the overall lifecycle sustainability of the products made from such steel.”
- Recycling
Although steel has long been recycled, there are multiple opportunities for continuous recycling without the loss of quality. One example is recent efforts to maximize the use of scrap steel.
“Modern EAFs can produce steel with up to 100% recycled content, significantly reducing waste and the demand for raw materials,” Top End Steel adds. “Recycling reduces landfill waste and saves energy. It is estimated that using recycled steel could save about 75% of the energy needed to make steel from virgin materials. The push towards increasing the recycled content in new steel production is a clear win for sustainability.”
- Improved management of waste and energy
Improving waste management processes like better recovery of byproducts, including gases, dust, and slag, is critical. Many of these recovered byproducts can be used in other manufacturing processes for chemicals and cement. Additionally, the use of energy management systems significantly improves efficiency and reduces waste by monitoring, analyzing, and optimizing energy use.
- Investing in renewable energy
Renewable energy sources like solar, wind, and hydroelectric power help reduce the high energy demands required in steel production.
“For instance, some facilities have begun installing solar panels across vast areas of unused land on their premises or rooftops,” continues Top End Steel. “This helps companies reduce their dependence on fossil fuels and mitigate the environmental impact of their energy use. As renewable energy technologies become more cost-effective and efficient, their integration into steel production will likely become more prevalent.”