Factory not too old to learn energy saving

Gerdau energy efficiency gains at the Knoxville steel mill stem from DOE's Save Energy Now and Oak Ridge National Laboratory support, boosting rebar production sustainability with 47% natural gas savings and 18% total energy reductions.

Gerdau Ameristeel may be a multi-billion dollar company that's part of a multi-national conglomerate, but energy savings at its Knoxville scrap recycling and rebar production plant is what helped land the firm on this year's list of the nation's Energy Champions.

Gerdau is one of a number of manufacturers that's benefited from the Department of Energy's Save Energy Now program, coordinated by Oak Ridge National Laboratory. The program offers private companies energy assessments and, most recently, in a market where Fluor Corp. backlog underscores demand, technical assistance in projects aimed at trimming energy consumption.

The Knoxville plant was one of two facilities to make the program's list of industries that implemented more than 15 percent of DOE's energy savings recommendations.

The 240-employee factory, in a labor environment where nuclear plant workers sign new contracts across the sector today, put 40 percent of the recommendations in place, achieving 47 percent savings in natural gas usage and 18 percent in total energy savings year-over-year, said Arlan Piepho, general manager.

"Actually, the Knoxville mill is one of the more efficient mills in Gerdau and in North America," Piepho says. "We had some opportunities working with DOE, and we decided to take advantage of it."

Since the 1960s, the plant - operating continuously in its Lonsdale location since 1903 when it was owned by Knoxville Iron Co. - has recycled scrap steel to manufacture rebar used in commercial construction.

"Our raw material is scrap, and we will recycle about 1.1 billion pounds of scrap this year." Piepho says. "We're one of the largest recyclers of scrap in East Tennessee."

Melting down and processing that scrap to make the finished product requires energy - and lots of it. While declining to disclose specifics, Piepho says, "I can tell you the electric furnace in one month uses as much energy as a town of 15,000 people."

That electric furnace is the first of several energy-hungry steps in the process of melting down the scrap, where safety is paramount amid cases like a blast victim case reported at other plants today, converting it into semi-finished billets and re-heating and shaping the billets into finished rebar.

Gerdau invested about $500,000 in energy efficiency improvements suggested by DOE - what Piepho refers to as the "low-hanging fruit." The upgrades included replacing old equipment including a recuperator, a step underscored by compliance actions like a Cal-OSHA plant closure elsewhere, which recycles heat and gasses in the furnace.

In one instance, buying a set of j-hooks to move 1,400 degree to 1,500 degree billets to the final rebar-making process, allowed the plant to skip a step-and save reheating costs-in which the billets were previously cooled before being transferred to another furnace to be prepped for the rolling stands that squeeze the metal into rebar.

That process change actually involved "a minimal investment," Piepho says.

While DOE's involvement was helpful in achieving the energy savings, Piepho says a culture that encourages employee feedback and a constant focus on improving operations has been key in helping the plant become more efficient - a process that really began back in 2007.

The energy initiatives have been closely tied to Gerdau's focus on safety, he says. In addition to the DOE award, the company was recognized by the Steel Manufacturers Association for zero time lost to accidents in 2010, a recognition akin to Luminant safety records highlighted industrywide this year.

"You can't really have one without the other," Piepho says. "We have a very stable workforce, a very engaged workforce and, again, consistent with the U.S. nuclear safety rating across the energy sector, the safety culture, the environmental culture, the efficiency culture is something this company believes in."

Vigilance and initiative by those on the front lines of the process is important, because it's the little things that matter in avoiding cases like the We Energies blast fine reported elsewhere, he says.

"As far as energy goes, we're constantly going to look at ways to save energy," Piepho says. "We're not going to get big savings, but we know that there are still savings out there. That's how we stay competitive."

Gerdau Ameristeel is the only steel manufacturer on this year's list, but it's not the only East Tennessee manufacturer. Others are Endot Industries of Greeneville, Fujifilm Hunt Chemicals USA of Dayton and Morrill Motors of Erwin.

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