The issue of how reactors handle hydrogen gets airedIn the annals of journalism, improbable news stories are categorized by the headline “Man bites dog.” It signals the reversal of the normal flow of events and challenges to the logic of daily life.
Of course, the headline has been the butt of many jokes, “Man bites dog at county fair,” says Mayor Billy Bojangles, “it was a corn dog. Ha ha.”According to Wikipedia, the phrase was coined to describe the fact that you never read about a plane that did not crash and you don't hear about cases where a politician kept his pants on and his hands out of the till.
The phrase was reportedly first spoken by Alfred Harmsworth, a British newspaper magnate, but is also attributed to New York Sun editor John B. Bogart (1848–1921): "When a dog bites a man, that is not news, because it happens so often. But if a man bites a dog, that is news.So when the New York Times writes that U.S. nuclear utilities are complying with requirements from the Nuclear Regulatory Commission (NRC) regarding the control hydrogen in reactor pressure vessels, why is that news? But if an anti-nuclear group claims that the NRC’s requirement itself it unsafe,does that make it news? Maybe.
The newspaper seems motivated to run to ground a charge that the NRC acted against the interests of safety. It turns out the charge by the consultant at Beyond Nuclear is without merit, but the newspaper printed the story anyway.Maybe the newspaper’s original intention was to debunk the charge? I’d like to hope so, but it’s not easy to draw that conclusion from the way the material is presented to readers. Of course, the newspaper would say it is just reporting the news.
I suggest a new headline for this story should be “man did not bite dog” or something like that. It would make a lot more sense and tell a truer story.So why is the story news?
The multiple hydrogen explosions (Unit 3 right) at the Fukushima nuclear reactor complex in the days following the massive earthquake and tsunami that devastated the area March 11 were alarming visually, but caused little real damage to the part of the reactor that matter.So far as experts in the U.S. with direct on-the-ground knowledge of the situation in Japan know, the two pieces that count – the reactor pressure vessel and primary containment – are still intact at Fukushima reactors units 1-4.
The hydrogen explosions were caused because the level of cooling water dropped inside the reactor pressure vessels, and in the damaged spent fuel pool at unit #4, uncovering the fuel rods. The fuel rods are bound together with zirconium.When it gets too hot from the residual heat of the fuel assemblies, zirconium interacts with the water to oxidize claiming the oxygen and releasing hydrogen. Hydrogen is a volatile gas and is easily set off with explosive results from a variety of sources including sparks from static electricity.
As a practical matter, even if the reactors at Fukushima had hydrogen recombiners retrofitted into the plants, there was no electricity to run them to harmlessly vent hydrogen gas out the stacks. The tsunami that breached the seawall by two times its height wiped out the fuel supply for the emergency diesel generators shutting them off.Safe control of hydrogen
The safety issue for U.S. reactors is how to control the hydrogen, or vent it, in the case of an accident. The New York Times ran a story March 31 which was based on an allegation by a representative from an anti-nuclear group that the U.S. Nuclear Regulatory Commission (NRC) had failed to require nuclear utilities to properly deal with the risks of hydrogen explosions. The problem with the allegation, as detailed in the news report, is that isn’t true.The story begins with a statement by Paul Blanch, a Hartford, Conn., energy consultant, who's work has been prominently featured on the website of Beyond Nuclear, an NGO which is stridently opposed to the use of nuclear energy.
“The change in commission policy was pointed out this week by a nuclear safety critic, Paul M. Blanch, who said that he had been involved in installing such equipment at Millstone 3, a nuclear reactor in Waterford, Conn.“Post-Three Mile Island, they were considered very important to safety,’’ Mr. Blanch said. He accused the Nuclear Regulatory Commission of having “gutted the rule’’ because the industry wanted to save money.“
The newspaper also quotes a spokesman from the NRC.“They [recombiners] weren’t needed for design basis accidents and they didn’t help with severe accidents,’’ Mr. Brenner said.”
Nitrogen is an inert gasWhen the primary containment structure is filled with nitrogen, which is a common practice, then even if hydrogen is generated in there it cannot ignite in an inert atmosphere. It follows that it makes sense to drop the requirement to have hydrogen recombiners.
Yet, the newspaper ran with a story that suggest the NRC acted against the interests of safety at reactors when in fact the regulatory agency was reasonable in its logic.
TMI or refinery fire?Also, the use of a photo of TMI with the article is at least gratuitous or does it seem obligatory for editors these day when publishing something about the U.S. nuclear industry.
This is no different than CBS and CNN running pictures of a refinery fire in Japan for voice-overs about the status of the Fukushima reactors. It is a form of sensationalism and has no place in reporting about industrial accidents.# # #