Zirconium

Zirconium is a metallic element that has been used extensively in light water reactors for fuel cladding.  It is the first line of defense against radioactive fission products entering the environment. (BWT the second line of defense is the reactor vessel, usually about 4 inches of steel, and the third is the containment building of thick reinforced concrete and lined with around an inch of steel.)

Zirconium is virtually transparent to neutrons, so it doesn’t absorb them in the fission process and it has good heat conduction properties to allow the fission heat to leave the fuel rods and be transferred to the primary coolant.  The zirconium is made into long tubes that contain the uranium oxide fuel pellets.  The fuel rods are then assembled into groups called bundles, with dozens of bundles forming the core of the reactor.

The zirconium rods and bundles are a work of art, IMO.

Nuclear fuel rods and bundles

I also imagine that all this beautiful, precision metal work costs about the same as Rolex watch parts – a lot!

One of the advantages of molten salt reactor technology it that all this expensive zirconium is not needed.  The molten fuel is not contained in rods or tubes or bundles.  The level of safety will still be defense in depth, but should be considerable cheaper without all the Rolex parts.

My apologies to a local company, Western Zirconium, that is a subsidiary of Westinghouse Electric and produces zirconium from the minerals in the Great Salt Lake.  In the somewhat distant future we will not be needing so much zirconium when molten salt reactors come into their own.  In the meantime, they can make zirconium hydride control rods for WAMSR. (I owe my readers a post about WAMSR in the near future.)

I am not too worried about Western Zirconium in the near future, since Westinghouse sold all the zirconium metallurgical technology to the Chinese along with the AP-1000 reactors being built in China.  Providing fuel assemblies for those reactors should keep Western Zirconium plenty busy.

BTW, here are some cool pictures I took of the evaporation ponds that Western Zirconium uses in their process to extract zirconium from the mineral rich Great Salt Lake.

Western Zirc flying 068 Western Zirc flying 065 Western Zirc flying 061 Western Zirc flying 055Note: The Northern Arm of the Great Salt Lake is red from algae in the very salty water.

bwr

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