[HN Gopher] BYU profs create new nuclear reactor to produce nucl... ___________________________________________________________________ BYU profs create new nuclear reactor to produce nuclear energy more safely Author : sergiotapia Score : 40 points Date : 2022-10-06 21:24 UTC (1 hours ago) (HTM) web link (news.byu.edu) (TXT) w3m dump (news.byu.edu) | idiotsecant wrote: | The basic problem for molten salt reactors is that the various | reactor components are exposed to hot salts that are chemically | corrosive, while being bombarded by radioactive particles. This | is of course quite problematic when your goal is a machine that | makes electricity consistently for decades. Equipment failures | are an inevitability because we don't know of a material that has | the properties needed to survive this kind of application. | Curious how (or whether) the authors of this design approached | this problem. | 9wzYQbTYsAIc wrote: | The newly oublished patent is for something described as a | "salt wall" if that helps your imagination. | [deleted] | jakedata wrote: | Typical university press release doesn't provide any actually | useful information. They have not created anything yet. They have | a theoretical design. Good for them I guess. | SeanLuke wrote: | Well they still might build it I imagine. Back in the 1960s BYU | had a working nuclear reactor right on campus which produced a | few watts of energy. The underground facility was standing at | least as recently as the early 1990s. | themodelplumber wrote: | I remember hearing about that, and related rumors from | coworkers at BYU. They'd point out the guesstimated location | as we drove around campus in our work vehicle. | | This always dovetailed really nicely, in our opinion, with | the plain-as fact that Zion and her people would eventually | become the envy of the world and could already easily out- | engineer the best engineers that any first-world nation could | muster. | | The same sentiments were shared in classrooms with the topic | of internet backbones "coincidentally passing right through" | Utah. Why was it so? Well because the Lord would insist upon | only the finest internet for his finest priesthood-engineers | in the latter days, of course. Do your home teaching! | | There were lots of lovely little cultural side-alley | discussions like these. | fatcat500 wrote: | > If there is not enough of a flow of cooling water, the rods can | overheat, and the entire facility is at risk for a nuclear | meltdown. | | This is not true. Water is the moderator in a light-water | reactor. Without water the reaction will stop. Water is both the | coolant and the moderator, unlike the Chernobyl reactors, which | used graphite as the moderator. | gh02t wrote: | What you say is technically true but you're forgetting decay | heat. The fission chain reaction stops if you remove the | moderator in any sane LWR design, but the fission products in | the fuel will continue to generate a very large amount of heat | for quite a while. This is exactly what happened at Fukushima | and TMI. | | https://en.wikipedia.org/wiki/Decay_heat#Power_reactors_in_s... | | Some reactor designs can dissipate this decay heat with passive | circulation, while most require active pumps to circulate for a | while after shutdown. But a total loss of coolant is probably | going to result in fuel melt to some extent. | hairytrog wrote: | Which is equally a problem for a molten salt cooled reactor. | If molten salt leaks or pumping stops, you're gonna get a | melt down in your molten salt reactor. That is unless it's | running at super low power density - like these guys: | https://www.usnc.com/mmr/, in which case no cooling fluid or | pumps or even natural circulation apparently are needed to | keep it from melting. | gh02t wrote: | MSRs have an advantage though, which is that a) fuel melt | is obviously not a problem and b) if something goes out of | control you can pull the drain plug and drain the entire | core into multiple crit-safe storage pools. Dividing the | core up makes it easier to handle the decay heat, though | I'm not sure exactly what any of the current designs do in | detail. Fission product gasses are also not soluble in most | of the fuels for MSRs which makes it easy to filter them | out, which reduces the decay heat to an extent and also | mitigates the reactivity feedback effect from xenon that | caused the Chernobyl disaster. | | Not that it's all sunshine and roses, hot salts are awfully | corrosive and that's been the primary engineering challenge | on every MSR design I'm aware of. | hairytrog wrote: | Molten-salt-fuel reactors, as described in this article, are so | lame... "It's already melted, so you can't have a meltdown." lol. | More seriously, molten-salt-cooled reactors have some promise. | They use solid fuel, usually TRISO particles, and are cooled by | molten salts, which we now have lots of experience with from | solar salt power systems. If you are interested in molten-salt- | cooled reactors outside of this lame press release - check out | Kairos Power. Their website sucks butt. But they are the main | player in molten salt-cooled reactors - funded by Henry Laufer of | Renaissance Technologies. They actually have the engineering and | financing to get one built, and are reportedly doing very well | with NRC (unlike OKLO - lolz). | sergiotapia wrote: | >A typical nuclear power plant is built with a little over one | square mile to operate to reduce radiation risk, with the core | itself being 30 ft x 30 ft. Memmott's molten salt nuclear reactor | is 4 ft x 7ft, and because there is no risk of a meltdown there | is no need for a similar large zone surrounding it. This small | reactor can produce enough energy to power 1000 American homes. | The research team said everything needed to run this reactor is | designed to fit onto a 40-foot truck bed; meaning this reactor | can make power accessible to even very remote places. | | Sounds too good to be true! Wonderful news | gh02t wrote: | Worth noting that this is not really unique to this reactor, | and the technology has been around for a while (including | multiple basically fully functional demonstration reactors that | were actually built, though they weren't without their | technical issues). NuScale's design for example, which is a | very different design and also much closer to commercial | rollout, has a similar greatly reduced need for a large | exclusion zone (https://www.nei.org/news/2018/nrc-staff-agrees- | smrs-wont-nee...). | | This article is reporting on what amounts to a paper reactor | design, which is really only like 0.1% of the effort required | to actually _build_. There are plenty of good design concepts | for new and fancy reactors, but the business, regulatory, and | PR side is where the challenges really lie. But this general | technology is a big deal in the nuclear industry right now and | it seems increasingly likely that they might finally build some | fully functional plants. Strictly speaking they _are_ actively | building some MSR plants, but given the not great track record | of actually completing new nuclear plants I will remain | pessimistic until they are ready to go critical. | hairytrog wrote: | Not sure it's a justified reduction in exclusion zone. Yes | they use natural circulation to get rid of decay heat if they | lose power to run the pumps. BUT - they can't tolerate | multiple reactors failing at once, they can't tolerate more | than a few control rod withdrawals, and they can't tolerate | clogging of the flow channels - Which to me, seem like | reasonable accidents. The reduction in exclusion zone for | NuScale is not really justified. If they get a reduction, you | can expect the big ass reactors to also get a reduction... | gh02t wrote: | I don't really have an opinion on the matter and I think | it's a fair question to consider, but I'll note that the | NRC obviously disagrees. At least for now, they could | always change their mind. I _seriously_ doubt that they | would ever significantly reduce the exclusion zone | requirement for any of the currently operating reactors, | however. | hairytrog wrote: | I think that's fair. I bet new large power plants will | get the NuScale treatment and reduced exclusion zone | though. | jbverschoor wrote: | What's different in the actual design of the tractor compared to | other MSRs/LFTR? No talk about any of this | moffkalast wrote: | MSRs can do everything except leave the impossibly heat and | corrosion resistant lab. | | Maybe we should just build them in orbit without containment | and let the surface tension hold it together or something. | jbverschoor wrote: | But the article is talking about MSR | moffkalast wrote: | Only mentions something about making them smaller, not sure | how that would solve the core (pun intended) issues. | 9wzYQbTYsAIc wrote: | If you look for the actual design, you will come across a | newly published patent in the name of the mentioned | researcher. | 9wzYQbTYsAIc wrote: | If you read the article, you would see that the MSR design | would allow for recycling of the salt and the extraction of | the valuable byproducts. | | Also, this reactor is designed to fit onto a 40-foot truck | for transport to remote areas and can power up to 1000 homes. | moffkalast wrote: | Not sure how that helps if it melts through the floor, the | truck, and then the ground when you turn it on. Those are | nice improvements, but adding a red paint job to a wingless | plane won't make it fly. | | Suppose you could use some kind of ablative material, but | that would mean short runtimes and constant expensive | refits. Sort of like taking that wingless plane and | launching it with a trebuchet. Technically makes it fly but | not in any way that matters. | 9wzYQbTYsAIc wrote: | According to his patents, the molten salt is the coolant | and it would flow multiple stages of salt through the | system. | | https://patents.justia.com/inventor/matthew-memmott | [deleted] | eecc wrote: | Molten salt reactors are nothing new. It would be truly wonderful | if these folks solved the corrosion issues associated to | circulating high-temperature molten salts, and the ever-recurring | military-grade fuel proliferation risk associated with spent fuel | reprocessing. | spencercwood wrote: | I found another article that talked about corrosion: | | > While the DoE is still investigating ways to get around these | showstopping corrosion issues, Prof Memmott said that his team, | along with Alpha Tech Research Corp (the commercializing | partner for the BYU MSR, and of which Memmott is director and | senior technical advisor), believe they have solved the problem | by removing water and oxygen from the salt, massively reducing | the corrosion issue. | | https://www.theregister.com/2022/10/05/micro_molten_salt_rea... ___________________________________________________________________ (page generated 2022-10-06 23:00 UTC)