tag:blogger.com,1999:blog-2219176247590074617.post6967725798261655543..comments2024-03-29T01:36:24.591+01:00Comments on SunnivaRose: Fission on a Friday, part 2 (10 FACTS)Sunnivahttp://www.blogger.com/profile/03788574038633535127noreply@blogger.comBlogger1125tag:blogger.com,1999:blog-2219176247590074617.post-54123847536418786012015-09-04T21:55:47.320+02:002015-09-04T21:55:47.320+02:00Fascinating. I had no idea that fast-spectrum fis...Fascinating. I had no idea that fast-spectrum fission, in addition to releasing more neutrons per fission, has a substantially different mass-distribution in the fission products compared to thermal-spectrum fission.<br /><br />Something that's been intriguing me about thorium is the potential for using it in new fuel formulations for existing LWRs. LEU fuel for LWRs currently uses "burnable poison" like gadolinium to bring down the reactivity of the fresh fuel; otherwise the enrichment would have to be very limited and the fuel would have to be changed much more frequently. But instead of using burnable poison, why not use fertile material like thorium? This would also flatten the curve of reactivity vs.burnup as burnable poison does. But there would be two more salutary effects: it might extend the useful life of the fuel quite a bit, and it would create a stock of material that could be "mined" for bulk supplies of U-233.<br /><br />I lack the depth of subject-matter knowledge to analyze this idea in detail. However, the potential shown by the light-water breeder experiment run at the Shippingport reactor from 1977-82 is enormous. If I understand correctly, the reactor ran for 4 full-power years without so much as re-arranging the core. It finished the run with 1.4% more fissiles than it had when it started. If such cores can be scaled down for units which are passively safe, there is the prospect of "heat batteries" which could run for many years with little or no attention to what's inside. Passively-safe heat batteries could be located inside cities, providing both electric power and heat for space heat and hot water. All this energy would be carbon-free, emissions-free, requiring the occasional truck-load of fuel (or possibly whole "heat batteries") in and out: no fuel pipelines, no trains or ships carrying daily or weekly loads of combustible minerals. Clean, compact, trouble-free... practically the stuff of Eden.Engineer-Poethttps://www.blogger.com/profile/06420685176098522332noreply@blogger.com