Sustainable resolve

Waupaca Foundry Inc., headquartered in Waupaca, Wisconsin, produces iron castings largely from scrap metal for use in the transportation, construction, agriculture and industrial markets. The company, which has been owned by Tokyo-based Hitachi Metals Group since 2014, says it is committed to continuous improvement and dedicated to “advancing technology, safety and productivity.” One item missing from that list is sustainability.

An original recycler

Founded as Pioneer Foundry in 1871 by John Rosche on the banks of the Waupaca River, the company took the Waupaca Foundry Inc. name in 1955 when Clifford Schwenn purchased it.

Waupaca Foundry operates six iron casting foundries and two machining facilities in Wisconsin, Indiana, Tennessee and Illinois, as well as a plant in Ironwood, Michigan, where castings produced at its Waupaca foundries are cleaned and finished. Recognizing that capacity exceeded demand, in the summer of 2020, the company closed a seventh foundry in Lawrenceville, Pennsylvania. That plant primarily made automotive suspension components.

Waupaca Foundry says it melts up to 9,500 tons of iron daily across its six foundries.

Brian Powell, director of procurement and supply at Waupaca Foundry, says, “Approximately 85 percent of the materials used in our melt process come from recycled materials.”

He notes that in its 2019 fiscal year, Waupaca Foundry consumed 1 million tons of steel scrap in the production of its various grades of gray iron and ductile iron, including Hitachi Metals HNM Series high-strength and austempered ductile iron. Other metallic inputs include pig iron and copper.

The company purchases ferrous scrap from the automotive, appliance and general scrap market, Powell says, which includes tin cans.

“Melting 9,500 tons daily requires multiple strong partners,” he says. “Waupaca Foundry aims to source locally where, and as often as, possible. At any given time, there is only a four-hour supply of feedstock on the ground.”

According to Waupaca’s annual sustainability report, 8 of its top 10 supplier relationships go back 25 years or more, and all suppliers are certified through a documented process.

Waupaca employs two types of melt processes—induction, or electric, and cupola.

“The advantage of electric melt is the flexibility for frequent material changes and starts/stops,” he explains. “Cupola melting is still generally recognized as the most economical melting process if the furnace is operated continuously, such as is the case at Waupaca Foundry.”

Powell adds that even though the cupola process is 300 years old, it is the more efficient of the two processes and the primary method used at Waupaca.

Given its use of continual and large batch melting, he says Waupaca Foundry has high standards for its scrap. “There is an audit and review to ensure tramp [metals] are to the specification that allows Waupaca to meet our customers’ high quality standards,” Powell says. “It all starts with melt, and we work closely with our partners to ensure their standards are met.”

Waupaca Foundry Director of Environmental Engineering Bryant Esch says the company melts approximately the weight of the Eiffel Tower daily across its operations.

When scrap enters the company’s foundries, Esch says, it is sorted and sized “so it is optimal for our process,” which helps the company maintain production.

While he describes scrap usage as “one of the major cogs of sustainability” at Waupaca, it is not the only one.

Sustainable beyond scrap

Despite its significant use of ferrous scrap, Waupaca acknowledges that foundries also consume a good deal of energy and water and produce wastes, including foundry sand, which is why it has focused on the following sustainability goals for its 2020 fiscal year, which ends March 30:

• reduce energy use by 25 percent;
• reduce water use by 80 percent;
• promote alternative processes and maintain advanced pollution control technologies; and
• reduce spent foundry sand generation by 30 percent while promoting off-site reuse/recycling opportunities for remaining spent foundry materials.

Esch says that as of early January, Waupaca has achieved a 23 percent reduction in its energy use relative to 2010 and earned a U.S. Department of Energy 2020 Better Project Award for a system that removes humidity from the air entering the cupola at its Tell City, Indiana, foundry.

The federal program recognizes manufacturers for creating and implementing industrial energy and water efficiency projects, as well as renewable energy and energy resiliency projects.

Esch says plant engineers installed a desiccant cupola blast air drying system that removes water vapor from ambient air prior to introduction to the foundry’s cupola, enabling the company to use less energy in the form of coke in the melting process. “Every pound of water removed equals a certain amount of coke reduction,” he says.

“The system passes air through a desiccant air wheel which works like a filter to remove water from the air, increasing the efficiency of the combustion process,” Marco Gonzalez, corporate energy manager for Waupaca Foundry, says in a news release the company distributed after receiving the award in June of last year. “It’s like if you’re trying to light a barbecue during a rainy day, the moisture in the air will consume power from your charcoal and they will take longer to light. By removing the moisture from the air, the fuel can burn more efficiently.”

The cupola system also is designed to recover and return waste heat to the cupola’s melting zone, which further boosts the system’s energy efficiency, Esch adds.

In addition to the energy savings, the system reduces ash and solid waste produced during the melting process, he says.

The melting process represents 65 percent of the Tell City foundry’s total energy usage, with coke being the largest source of energy.

In addition to supporting the direct melting processes, excess “waste” heat from the cupola furnace supplies building heat and is used to heat water at Waupaca Foundry facilities in cold months. Heat recovery systems used at Waupaca plants provide 70 percent of the foundries’ space heating requirements and 100 percent of the plants’ hot water needs.

Esch says the company also wanted to reduce fresh water use in foundry pollution control and noncontact machine cooling applications. Each of the company’s foundries in Waupaca used 1 million gallons of water per day for these purposes. Plant upgrades substituted these single-use water cooling systems with closed-loop and air-cooled heat exchangers, cutting water demands by 67 percent, Esch adds, and reducing noncontact cooling water discharge to near zero.

The company’s sustainability efforts also have been recognized by the American Foundry Society, Schaumburg, Illinois. In 2020, Waupaca Foundry was awarded the Green Foundry Sustainability Award for initiatives that included implementing the ISO 50001 Energy Management System, a formal management system approach to energy reduction. To gain the ISO certification, the company says it created and implemented a program in energy management at its gray iron foundry Plant 1 in Waupaca and then reviewed and checked data to ensure consistent results. After 12 months of preparation and a verification audit by an independent registrar, the certification was granted in 2017.

Waupaca Foundry also recycles 450,000 tons of foundry byproducts annually, including sand. One grain of sand can be recycled approximately 50 times internally at the company’s foundries by cooling and reconditioning it, Esch says.

Sand that can no longer be recycled internally at Waupaca’s foundries is removed from the process for use in general construction, road construction, agricultural use and geotechnical fill, according to the company. About 75 percent of Waupaca’s sand goes off-site to be used in these applications.

The company’s sustainability initiatives and its focus on continual improvement have helped to position the company for future growth, Esch says.

Room for growth

“Waupaca will continue to expand in markets in support of its customers’ growth,” Powell says. “This will be realized through key strategic capital investments throughout our facilities. And it can be seen in new technology, such as expanded use of automation, which carries positive social and environmental impacts.”

Upon completion of its 2020 sustainability goals, he says new three-year targets will facilitate ongoing improvements. “Waupaca is also investigating the procurement of long-term renewable energy, such as solar and wind power, using variable power purchase agreements, as well as to maximize the use of waste heat to work towards a carbon-net-zero business model.”

While sustainability will factor into the company’s future, Powell says Waupaca Foundry’s ongoing use of scrap could be challenged by the growing use of specialty metals in many industries. “The more high-strength steel, the more challenging it will be to use a straight scrap supply to melt iron. This indicates more reliance on virgin materials like pig iron, direct reduced iron, etc.,” he says.

For the time being, global trade issues are affecting scrap metal pricing.

Powell says, “The industry supports a global supply chain. Components and commodities move all over the globe.” However, tariffs have affected U.S. metal producers’ ability to sell globally, he adds. “The economic conditions created by tariffs artificially decrease demand with fewer buyers. This puts all the control in the U.S. mill market. We have seen dramatic raw material price increases recently. We expect this volatility will continue in 2021, which began in December 2020.”

However, the company does not view the growth in electric vehicle (EV) demand and production as a potential challenge, with Powell noting that EVs that run only on batteries are forecast to be just 10 percent of the vehicles produced in 2030. “[U]ntil then, [internal combustion] engines will still be installed, including [in] hybrid vehicles. Parts for internal combustion engines will continue to contribute to our portfolio.”

While EVs could lead to decreased demand for some engine components, the company says iron castings will remain in demand for suspension, braking and driveline components. Additionally, Waupaca says a hybrid-electrification model could present opportunities for new iron components.

Infrastructure impacts arising from EV growth also could increase demand for municipal, construction and other industrial components that the company manufactures. Because Waupaca Foundry is diversified across multiple market sectors, the company says it is well-positioned to adapt to these changes.

The author is editor of Recycling Today and can be reached at dtoto@gie.net.