Richland’s Areva is a quiet giant in electricity production.
Fuel rods made at by the Tri-City area’s largest manufacturer are used to create about 5 percent of the nation’s energy.
Each rod’s diameter is slightly narrower than a dime, but is 12 to 14 feet long. And it’s made to withstand the environment of a nuclear reactor and produce energy for about six years.
Most of the Richland’s plant 700 employees are dedicated to helping make about 200,000 fuel rods a year for use in nuclear utilities in North America and the Pacific Rim.
The Richland facility is one of three Areva fuel fabrication plants around the world. The other two are in France and Germany. The company also is a partner in a number of fuel fabrication facilities.
“Areva is the largest nuclear supplier in the world,” said Ron Land, Areva senior vice president.
Richland has been home to a nuclear fuel producer for the past 45 years, but the site now belonging to Areva has been owned by more than a half-dozen companies.
Areva bought the Richland fuel fabrication facility in 2001, and started modernizing the plant. The result, Land said, is a state of the art facility on the world stage.
The Richland site includes about 40 buildings and facilities on about 47 acres. The buildings cover about 400,000 square feet.
The basic recipe for making nuclear fuel has remained about the same, but how it is done hasn’t. New technology is being used, including some developed by Richland employees through the years. Some of that technology is considered the best practice for worldwide nuclear fuel production.
“We are very proud of our technology here,” Land said. “It is all aimed at improving safety, improving quality, reducing the impact to the environment.”
Each batch of fuel is custom made to fit the requirements of the utility that will use the fuel, Land said. In some cases, the way the fuel rods are assembled appears the same but the levels of uranium within the fuel rods are different.
“We build all kinds of nuclear fuel,” said Barry Tilden, Richland operations manager.
Areva starts out with an enriched form of uranium called uranium hexafluoride. The uranium is enriched elsewhere and transported to the Richland facility in cylinders. Each can carry about 2.5 tons of uranium hexafluoride.
Then, the uranium is at such a low level of radioactivity that someone could hold it in his or her hand and be fine, Land said.
The enriched uranium is chemically changed using a dry conversion process into a uranium dioxide powder. The dry conversion process was among those invented at the Richland site, and is better when it comes to economics, environment and safety, Land said.
The powder is pressed into pellets no more than an inch long. The pellets go through a sintering furnace for about eight hours, bringing them higher than 1,500 degrees C, holding them at that temperature, and then cooling them down. That bonds the powder together.
The pellets are loaded into the fuel rods by a machine that vibrates and shakes the pellets into the rods. Helium gas is inserted into the rods before the open end is welded shut.
The company’s high tech machine shop also makes the structural parts needed for nuclear fuel rods assemblies using computer-controlled robotics, Land said.
Among the parts made are the tie plates used on the top and bottom of fuel assemblies.
The structural materials used for the fuel rods and arrays is mostly zirconium, a material resistant to corrosion and strong. It also does not absorb neutrons, a critical characteristic since conserving neutrons helps nuclear fuel utilities keep the chain reaction of fission going steadily.
Areva also makes control rods of boron or cadmium that are inserted into the fuel assemblies if a nuclear utility needs to pause the fission process. The control element assemblies absorb the neutrons that are part of the fission process.
The fuel that leaves Areva for worldwide customers is unradiated fresh fuel, which means it is still minimally radioactive.
Still, fuel is packed in a licensed shipping container and transported by truck. Containers are tested before they can be used. Tests include fire, being dropped from 33 feet and being dropped onto a steel pin, trying to simulate possible accidents.
The nuclear utilities that buy Areva’s fuel install the fuel rod arrays into reactors. The fission process creates heat, generates steam and produces electricity.
Reactors typically operate about 18 to 24 months before a refueling outage. Most fuel rods will be used during three cycles, since only about a third of the fuel is replaced during an outage, Land said. The rest is shuffled around.
The spent fuel that has undergone the fission process is extremely radioactive, Land said.
Areva has seen some growth over the years, but it has been taking over more of the market share versus expanding within the industry, Land said.
Most of the nuclear plants were built in the 1970s and 1980s. Since then, a few have been built, but a few also have been shut down. It’s kept business steady.
In the past, Japan has been the Richland plant’s largest export market, but it hasn’t sent nuclear fuel to Japan in recent years.
Japan’s nuclear utilities haven’t operated since a major earthquake and a tsunami created a major nuclear accident at three reactors in Fukushima in March 2011.
Areva’s own impact to the environment is lower than one might expect. All of the liquid effluent from the plant is clean enough to go directly into the city sewer system. And the plant filters air before it is released into the environment, Land said.
Very little regulated waste is produced because Areva tries to recycle and use each and every bit of uranium. And the hydrofluoric acid produced as part of the process is sold to be used in semiconductor manufacturing, Tilden said.
Uranium is recovered from any scraps and used to make fuel. Areva incinerates combustible materials and recovers uranium from the ashes. And uranium also is recovered from the wash water used to clean the cylinders, Tilden said.
Nuclear fuel production is highly regulated. The federal Nuclear Regulatory Commission is the primary nuclear regulator and has inspectors at the Richland facility for about a week each month, Land said.
Regulation is an essential part of the process, according to Land. It’s important to be able to have an independent regulator verifying that companies like Areva are correctly handling and manufacturing nuclear materials.
The Richland fuel fabrication plant has not had a significant accident or event during its 45-year history.
“We place a premium on being prepared,” Land said. “Always better to be prepared and never use it as opposed to the other way around.”