It’s one of the biggest challenges the experts from Germany have ever faced: helping dismantle the nuclear power plant Zion about 30 miles north of Chicago.
Siempelkamp, a mid-sized company from the German city of Krefeld, is tackling the most demanding and sensitive task at the plant, which went offline in 1998 after more than 20 years of operation. Siempelkamp developed the method to dismantle both reactor blocks along with all the internal components, and the German experts are supervising the deconstruction.
After years of analysis, planning and the building of appropriate machines, now there’s a frenzy of sawing and other activity proceeding at the site on the Lake Michigan shoreline.
Siempelkamp, a company specializing in casting and compression molding, has plenty of experience in the nuclear sector. For decades, the family firm was one of the go-to subcontractors in the construction of nuclear power plants. But that business is on its way out, said Hans Fechner, spokesman for the company's management. “Nuclear power plants are no longer competitive, anywhere,” he said. The growth sector will be in demolishing the plants: “I expect a veritable boom in the coming years.”
The company, with annual revenues of about €600 million ($661.6 million), has been giving external expression to this transformation as well. The former subsidiary for nuclear technology has become Siempelkamp Engineering and Service Co.
“We were at a dead end with the old nuclear technology,” Mr. Fechner said. “The energy transition is forcing not only large providers like RWE, but also us to reorganize ourselves completely.”
In two years, the renamed subsidiary will have around 500 employees, about 100 less than now. In the future, the engineers are supposed to become increasingly involved in the exit from nuclear energy. In the dismantling of shut-down nuclear power plants, these specialists focus particularly on removing the components of the primary circulation ― the parts that were exposed to the most radiation.
Nuclear power plants are no longer competitive anywhere. Hans Fechner, Siempelkamp spokesman
Siempelkamp provides the software for calculating expenses, assumes responsibility for planning personnel assignments, schedules and machine utilization, and tasks its experts with supervising the dismantling over a number of years.
The company carried out all these processes on the shore of Lake Michigan. Siempelkamp has developed a concept with two technical procedures for taking apart the containers of the reactor. Torches fueled by oxygen and propane can easily cut through special steel that is about two feet thick, and the process saves much time in breaking up components weighing tons.
The procedure was first tested in dismantling the nuclear power plant in the German city of Stade, where Siempelkamp was working with a subsidiary of E.ON. In addition, use is made of special band-saws as well as cutting and milling tools.
To protect the workers from exposure to radiation, the breakdown and transport occur under water or in shielded spaces. The machines are monitored via cameras and guided by a joystick.
The dismantled parts are then packed into radiation-secure containers made of cast iron ― likewise a product of Siempelkamp. Mr. Fechner said that because of its large percentage of graphite, the material has the advantage of slowing down the flow of neutrons in the contaminated material. What is more, cast iron is extremely robust, doesn't rust and can resist shocks and bending.
Mr. Fechner knows of what he is talking about. For years now, his company has been supplying large, round Castor containers for the transport and intermediate storage of highly radioactive waste to GNS, a fuel and nuclear waste disposal firm owned by the large German energy providers. Last September, Siempelkamp received a big order from GNS for the production of 70 Castor containers. But orders are also received from other countries such as Russia. The factory in the German city of Mülheim is working at full capacity. In this sector, Siempelkamp is the largest manufacturer in the world.
Mr. Fechner also forecasts a flourishing business for containers used for storing slightly radioactive material. At the moment, his company is producing around 100 of these large, radiation-shielding containers. “When dismantling operations really get up to speed in Germany, there will be increasing demand,” he said, adding he expects to be producing around 400 of them per year. “The demand will not dwindle until the problem of final storage has been solved.”
Mr. Fechner says Siempelkamp is focusing more and more on the dismantling process because of its philosophy: “We are a technology-driven company operating in the niche.” For the new engineering subsidiary, 2015 is a year of transition. The subsidiary had about €100 million in revenues last year. The company does far more business with complete plants for producing particle boards and with gigantic presses for automobile and airplane construction.
Mr. Fechner is optimistic about the future prospects for the dismantling of nuclear reactors: “In the United States, we acquired the know-how to be successful elsewhere as well.” There is plenty of work: in Germany alone, there are currently nine nuclear reactors that are scheduled to go offline by the end of 2022 at the latest. And eight more nuclear power plants that have already been switched off are still waiting to be dismantled.
Martin Wocher covers energy issues for Handelsblatt. To contact him: [email protected]