Pebble bed reactors work quite well and are meltdown proof. A core of enriched uranium pellets are surrounded by seven alternating layers of ceramic and graphite. Detractors of the design claim that there are always cracks in the layers. Big deal, that's why there are seven layers. The chance of all the layers having a crack, and all the cracks being perfectly aligned is essentially zero. In reactors of this type the pebbles are cycled through an automated inspection that tests for radiation leakage.
They use helium for transferring heat to an exchanger to heat water to steam, or use some other working fluid to run turbines. A benefit of helium is if there is a leak, the helium floats up. It can be let out of the building and will float harmlessly away. This reactor design can't melt down because the pellets are designed so they don't have enough uranium close enough together to sustain the level of fission required to get hot enough to melt. But the folks who know nothing at all about nuclear stuff and refuse to learn anything about it are against building these in the USA. On Sunday, March 10, 2019, 6:31:47 PM MDT, Jon Elson <[email protected]> wrote: On 03/10/2019 04:16 PM, Greg Bernard wrote: > Interesting stuff, Jon. Didn't know about the ongoing cleanup at Three Mile > but it doesn't surprise me. Now I'm going to put you on the spot. Given our > current need for carbon-free energy, do you see nuclear as a viable option? > > Yes! If a properly designed and built nuclear plant is run by a competent organization, I think they make a lot of sense. The French have been using nuclear power almost exclusively for 40 years, and their plants are WAY more modern than ours. They use a lot of gas-cooled reactors, which solve a WHOLE bunch of potential problems (loss of coolant and corrosion, mostly) and those have been doing just fine for years. We ought to rethink nuclear, and start using the newest technology. While it is not totally clean or risk-free, it is a lot cleaner than coal (which ALSO releases radioactivity into the atmosphere). _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
