Transcript

U.S. Steel Coke Plant Explosion Linked to Valve Procedure, Siting Failures

We first take a look at the U.S. Chemical Safety and Hazard Investigation Board’s final report on the Aug. 11, 2025, explosion at U.S. Steel’s Clairton Coke Works in Clairton, Pennsylvania. CSB found deficiencies in procedures, facility siting and process safety management contributed to the incident.

The explosion occurred during maintenance on a double-disc gate isolation valve supplying coke oven gas to Battery 13. U.S. Steel employees and contractors from MPW Industrial Services were attempting to exercise the valve, a process intended to confirm that it could fully close and reopen.

According to CSB, workers had developed an informal practice of applying pressurized water to valve cleanout ports when coke residue prevented valves from closing fully. The practice had been used for at least three years but was not included in the facility's written valve-exercising procedure, and U.S. Steel did not have a formal procedure for washing valves with pressurized water.

During the incident, workers applied pressurized water while the valve's two gates were closed or nearly closed. The water became trapped between the gates, increasing pressure beyond the valve's containment capability. The more than 70-year-old cast-iron valve then failed, releasing toxic and flammable coke oven gas. The gas ignited within minutes, causing the explosion.

Two workers were killed and 11 others injured, including five who suffered serious injuries. The incident also caused an estimated $52.5 million in property damage.

CSB identified inadequate procedures and hazard analysis, facility siting and deficiencies in process safety management systems as key safety issues.

The board recommended that U.S. Steel conduct a facility-siting evaluation covering occupied and potentially occupied buildings at Clairton and address identified hazards. It also recommended that the company establish a written procedure for washing valve seats with pressurized water and implement a comprehensive process safety management system for coke oven gas processes.

Research Revisited: Argonne's Cleaner Path to Critical Minerals

There’s gold in oilfield wastewater … or lithium, that is. Argonne National Laboratory researchers are advancing a separation process that could make it profitable to extract lithium and other critical elements out of the water generated by oil and gas operations, geothermal plants and battery recyclers.

Yuepeng Zhang, an Argonne principal materials scientist who is leading the research, wrote about the project in a July 2, 2024, Chemical Processing article called, “Extracting Critical Materials From Gas and Oilfield Wastewaters.”

Since then, the scientists have expanded their target elements to include cobalt, copper, nickel and semiconductor materials like gallium and germanium. These are elements on the Department of Energy’s list of critical minerals and materials considered essential for energy technologies.

The researchers also have shifted from absorption materials to direct extraction, which requires less energy and makes the process more efficient and cost-effective, according to Zhang.

The previous process relied on absorption materials with cavities that would bind with certain elements, enabling preferential complexing. That method works, but releasing the captured ions afterward requires considerable energy. Argonne's team is developing other selective layers focused on 2D materials, which either allow the desired element to pass through the membrane for collection or allow non-selective elements to pass through, leaving the target ion behind.

Argonne is in discussions with commercial partners to bring the technology to market. Zhang said the lab has not entered into a formal agreement with any collaborators but has submitted two proposals that are pending.

DOE Launches $100M Critical Minerals Workforce Initiative 

We close with an announcement from the Department of Energy’s Office of Critical Minerals and Energy Innovation. On Aug. 7 the agency announced a Notice of Intent for its Providing Opportunities for Specialized Education in Critical Technologies (PROSPECT) initiative. The program is intended to expand higher-education programs and develop workers needed across the domestic critical-minerals supply chain.

The initiative will support scholarships, financial assistance, curricula, teaching tools and other programs at colleges and universities. DOE said it’s looking to double the number of graduates with degrees related to mining, minerals and associated supply-chain technologies within two years.

DOE estimates the U.S. will need about 6,000 new mining engineers over the next decade. The agency also identified workforce shortages in materials science, mineral processing and recycling.

For chemical processors, the initiative could help address workforce needs in the downstream stages of critical-minerals production, where chemical engineering expertise is used for mineral separation, refining, extraction, recovery and recycling. Expanding domestic processing capacity also will require engineers and technicians familiar with unit operations, process control, materials handling and environmental and safety systems

That wraps up this month's top stories from ChemicalProcessing.com. Stay informed on the stories that matter most to the chemical processing industry. I'm Jonathan Katz, and this has been Distilled News.