Suyuq ftorli torium reaktori - Liquid fluoride thorium reactor

Suyuq FLiBe tuz

The suyuq ftorli torium reaktori (LFTR; tez-tez talaffuz qilinadi ko'taruvchi) ning bir turi eritilgan tuz reaktori. LFTR'lar torium yoqilg'isi aylanishi bilan ftor -yoqilg'i uchun asosli, eritilgan, suyuq tuz. Oddiy dizaynda suyuqlik juda muhim yadro va tashqi o'rtasida pompalanadi issiqlik almashinuvchisi bu erda issiqlik radioaktiv bo'lmagan ikkinchi darajali tuzga o'tkaziladi. Keyin ikkilamchi tuz o'z issiqligini a ga o'tkazadi bug 'turbinasi yoki yopiq tsiklli gaz turbinasi.^[1]

Eritilgan tuz bilan ishlaydigan reaktorlar (MSR) etkazib beradi yadro yoqilg'isi eritilgan tuzga aralashtiriladi. Ularni ishlatadigan dizaynlar bilan aralashtirib yubormaslik kerak eritilgan tuz uchun sovutish faqat (ftorli yuqori haroratli reaktorlar, FHR) va hali ham qattiq yoqilg'iga ega.^[2] Eritilgan tuz reaktorlari sinf sifatida ftorli yoki xloridli tuzga asoslangan yoqilg'idan va bir qatorda bo'linadigan yoki unumdor sarflanadigan materiallardan foydalangan holda tez yoki termal spektrdagi bruserlarni va selektsionerlarni o'z ichiga oladi. LFTRlar ftorli yoqilg'i tuzlaridan foydalanish va naslchilik bilan belgilanadi torium ichiga uran-233 termal neytron spektrida.

LFTR kontseptsiyasi birinchi marta tekshirildi Oak Ridge milliy laboratoriyasi Eritilgan-tuzli reaktor tajribasi 1960-yillarda, MSRE toriumdan foydalanmasa ham. Yaqinda LFTR butun dunyo bo'ylab yangi qiziqish uyg'otdi.^[3] Yaponiya, Xitoy, Buyuk Britaniya va xususiy AQSh, Chexiya, Kanada^[4] va Avstraliya kompaniyalari ushbu texnologiyani ishlab chiqish va tijoratlashtirish niyatlarini bildirdilar.

LFTRlar boshqa quvvat reaktorlaridan deyarli barcha jihatlari bilan farq qiladi: ular uranni to'g'ridan-to'g'ri ishlatish o'rniga, uranga aylanadigan toriumdan foydalanadilar; ular yonilg'i quyilmasdan nasos bilan to'ldiriladi.^[5] Ularning suyuq tuzli sovutgichi yuqori ish harorati va birlamchi sovutish pastasida bosimni ancha past bo'lishiga imkon beradi. Ushbu o'ziga xos xususiyatlar ko'plab potentsial afzalliklarni keltirib chiqaradi, shuningdek dizayndagi qiyinchiliklarni keltirib chiqaradi.

Fon

Torium Yer po'stida nisbatan ko'p.

Ning mayda kristallari torit, a torium mineral, kattalashtirish ostida.

Oak tizmasidagi eritilgan tuz reaktori

1946 yilga kelib, sakkiz yildan keyin yadroviy bo'linishni kashf etish, uch bo'linadigan izotoplar sifatida foydalanish uchun ommaviy ravishda aniqlangan edi yadro yoqilg'isi:^[6][7]

• Uran-235, bu allaqachon bo'linadigan, va 0,72% tabiiy ravishda uchraydi uran
• Plutoniy-239 bo'lishi mumkin tarbiyalangan bo'linmaydigan uran-238 (> 99% tabiiy uran)
• Uran-233, bo'linmaydigan narsadan olinishi mumkin torium-232 (~100% tabiiy torium; bu to'rt baravar katta Yer qobig'idagi mo'llik uranga qaraganda^[8])

Th-232, U-235 va U-238 ibtidoiy nuklidlar uchun hozirgi shaklida mavjud bo'lgan 4,5 milliard yildan ortiq, oldindan Yerning shakllanishi; ular yulduzlar yadrosida soxtalashtirilgan r-jarayon va tomonidan galaktika bo'ylab tarqalib ketgan supernovalar.^[9] Ularning radioaktiv parchalanish ning taxminan yarmini ishlab chiqaradi Yerning ichki issiqligi.^[10]

Texnik va tarixiy uchun^[11] sabablarga ko'ra uchtasi har xil reaktor turlari bilan bog'liq. U-235 dunyodagi asosiy yadro yoqilg'isidir va odatda ishlatiladi engil suvli reaktorlar. U-238 / Pu-239 eng ko'p foydalanishni topdi suyuq natriy tez ishlab chiqaruvchi reaktorlar va CANDU reaktorlari. Th-232 / U-233 eng mos keladi eritilgan tuz reaktorlari (MSR).^[12]

Alvin M. Vaynberg dan foydalanishga kashshof bo'lgan MSR da Oak Ridge milliy laboratoriyasi. ORNL-da ikkita prototip eritilgan tuz reaktori muvaffaqiyatli ishlab chiqilgan, qurilgan va ishlatilgan. Bular edi Samolyot reaktori tajribasi 1954 yilda va Eritilgan-tuzli reaktor tajribasi 1965 yildan 1969 yilgacha. Ikkala sinov reaktorida ham suyuq ftorli yoqilg'i tuzlari ishlatilgan. MSRE alohida sinovlar paytida U-233 va U-235 yonilg'isini namoyish qildi.^[13](pix) Vaynberg lavozimidan chetlashtirildi va MSR dasturi 1970-yillarning boshlarida yopildi,^[14] shundan so'ng Qo'shma Shtatlarda izlanishlar to'xtab qoldi.^[15][16] Bugungi kunda ARE va MSRE eritilgan tuz reaktorlari bo'lib ishlamoqda.

Naslchilik asoslari

A atom reaktori, yoqilg'ining ikki turi mavjud. Birinchisi bo'linadigan urishganda bo'linadigan material neytronlar, katta miqdordagi energiyani ajratish va shuningdek, ikki yoki uchta yangi neytronlarni chiqarish. Ular ko'proq bo'linadigan moddalarni ajratishi mumkin, natijada zanjir reaktsiyasi davom etadi. Bo'linadigan yoqilg'ilarga U-233, U-235 va Pu-239 misol bo'la oladi. Ikkinchi turdagi yoqilg'i deyiladi serhosil. Unumdor yoqilg'iga misol qilib Th-232 (qazib olingan torium) va U-238 (qazib olingan uran) olinadi. Parchalanish uchun avval ushbu nuklidlar kerak neytronni yutadi bo'linish jarayonida ishlab chiqarilgan bo'lib, mos ravishda Th-233 va U-239 ga aylandi. Ikki ketma-ketlikdan keyin beta-parchalanish, ular bo'linishga aylanadi izotoplar U-233 va Pu-239 navbati bilan. Ushbu jarayon naslchilik deb ataladi.^[5]

Barcha reaktorlar shu tarzda yonilg'ini ko'paytiradi,^[17] ammo bugungi qattiq yonilg'i bilan ishlaydigan termik reaktorlar, ular iste'mol qilinadigan bo'linish miqdorini qoplash uchun unumdorlikdan yangi yoqilg'ini ko'paytirmaydi. Buning sababi shundaki, hozirgi reaktorlar qazib olingan uran-plutoniy tsiklidan me'yorli neytron spektrida foydalanadi. Bunday yonilg'i tsikli, sekinlashgan neytronlardan foydalangan holda, ko'paytirilgan plutonyumning bo'linishidan 2tadan kam yangi neytronni qaytarib beradi. Parchalanish reaktsiyasini davom ettirish uchun 1 ta neytron zarur bo'lganligi sababli, yangi yoqilg'ini ko'paytirish uchun har bir bo'linish uchun 1 neytrondan kam byudjet qoladi. Bundan tashqari, yadro tarkibidagi materiallar, masalan, metallar, moderatorlar va bo'linish mahsulotlari ba'zi neytronlarni o'zlashtiradi, shu bilan reaktorda ishlashni davom ettirish uchun etarlicha yoqilg'i etishtirish uchun juda kam neytronlar qoladi. Natijada ular vaqti-vaqti bilan yangi bo'linadigan yoqilg'ini qo'shishlari va yangi yoqilg'iga joy ajratish uchun eski yoqilg'ining bir qismini almashtirishlari kerak.

Kamida qancha yangi yoqilg'ini iste'mol qilsa, shuncha ko'paytiradigan reaktorda yangi bo'linadigan yoqilg'ini qo'shish shart emas. Faqatgina yangi unumdor yoqilg'i qo'shiladi, bu reaktor ichida bo'linishga imkon beradi. Bundan tashqari, bo'linish mahsulotlarini olib tashlash kerak. Ushbu turdagi reaktor a deb nomlanadi selektsioner reaktor. Agar u abadiy ishlashni davom ettirish uchun unumdorlikdan shunchalik yangi bo'linishni ko'paytirsa, u "break-even" selektsioneri yoki izobreyder deb ataladi. LFTR odatda selektsion reaktor sifatida ishlab chiqilgan: tori kiradi, bo'linish mahsulotlari tashqariga chiq.

Uran-plutonyum yoqilg'isidan foydalanadigan reaktorlar talab qiladi tezkor reaktorlar naslchilikni davom ettirish uchun, chunki faqat tez harakatlanadigan neytronlar bilan bo'linish jarayoni bo'linish uchun 2 dan ortiq neytron beradi. Torium yordamida a yordamida nasl berish mumkin issiqlik reaktori. Bu ishlaganligi isbotlangan Shippingport atom elektr stantsiyasi, uning oxirgi yoqilg'i yuki standart darajada bo'lishiga qaramay, iste'mol qilinganidan toriumdan bir oz ko'proq bo'linishga olib keldi engil suvli reaktor. Issiqlik reaktorlarini ishga tushirish uchun qimmat bo'linadigan yoqilg'idan kamroq talab qilinadi, ammo yadroda qolgan bo'linish mahsulotlariga nisbatan sezgirroqdir.

Kerakli naslchilikni amalga oshirish uchun selektsioner reaktorini sozlashning ikki yo'li mavjud. Biror kishi unumdor va bo'linadigan yoqilg'ini bir joyga to'plashi mumkin, shuning uchun ko'payish va bo'linish bir joyda sodir bo'ladi. Shu bilan bir qatorda, bo'linadigan va unumdorlikni ajratish mumkin. Ikkinchisi yadro va adyol deb nomlanadi, chunki bo'linadigan yadro issiqlik va neytronlarni hosil qiladi, alohida adyol esa barcha nasllarni ko'paytiradi.

Reaktorning birlamchi tizim dizayni o'zgarishi

Oak Ridge eritilgan tuz ishlab chiqaruvchi reaktori uchun selektsioner yasashning ikkala usulini o'rganib chiqdi. Yoqilg'i suyuq bo'lgani uchun ular "bitta suyuqlik" va "ikki suyuqlik" torium termal selektsioneri eritilgan tuz reaktorlari deb nomlanadi.

Yagona suyuqlik reaktori

Bitta suyuqlik reaktorining soddalashtirilgan sxemasi.

Bitta suyuqlik konstruktsiyasida torium va uran bo'lgan ftorli tuz bilan to'ldirilgan katta reaktor kemasi mavjud. Tuzga botirilgan grafit tayoqchalari moderator vazifasini bajaradi va tuz oqimini boshqaradi. ORNL MSBR dizaynida^[18] reaktor yadrosi chekkasida grafitning kamaygan miqdori tashqi mintaqani mo''tadil holatga keltirishi va u erda neytronlarni torium tomonidan ushlanishini oshirishi mumkin. Ushbu tartib bilan neytronlarning aksariyati reaktor chegarasidan bir oz uzoqlikda hosil bo'lgan va neytron qochqinning maqbul darajaga tushirilganligi.^[19] Shunga qaramay, bitta suyuqlik dizayni naslchilik uchun ruxsat berish uchun katta hajmga muhtoj.^[20]

Selektsioner konfiguratsiyasida, parchalanish mahsulotlarini yoqilg'i tuzidan tozalash uchun keng yoqilg'ini qayta ishlash belgilangan.^[13](p181)Konverter konfiguratsiyasida zavod narxini pasaytirish uchun yoqilg'ini qayta ishlash talablari soddalashtirildi.^[19] O'zaro kelishuv davriy uranga yonilg'i quyish talabidir.

The MSRE faqat prototipli reaktor bo'lgan yadro mintaqasi edi.^[21] MSRE uzoq muddatli ish tajribasini taqdim etdi. Yaponiyalik olimlarning hisob-kitoblariga ko'ra, kichik suyuq bo'shliqlarni to'ldirish va MSRE bilan taqqoslanadigan kichik reaktor prototipini yaratish uchun tadqiqotlarni moliyalashtirish uchun 5-10 yil davomida 300-400 million dollarlik nisbatan mo''tadil sarmoyalar hisobiga bitta suyuq LFTR dasturiga erishish mumkin edi. .^[22]

Ikki suyuqlik reaktori

Ikki suyuqlik konstruktsiyasi "bitta suyuqlik" reaktori dizayniga qaraganda mexanik jihatdan murakkabroq. "Ikki suyuqlik" reaktori yuqori neytron zichlikdagi yadroga ega uran-233 dan torium yoqilg'isi aylanishi. Alohida adyol torium tuz neytronlarni yutadi va sekin uni o'zgartiradi torium ga protaktinium-233. Protactinium-233 neytron oqimi past bo'lgan adyol hududida qoldirilishi mumkin, shunda u asta-sekin U-233 bo'linadigan yoqilg'iga aylanadi,^[23] neytronlarni olishdan ko'ra. Bu tug'ildi bo'linadigan U-233 ni uran geksafloridini hosil qilish uchun qo'shimcha ftor yuborish orqali qaytarib olish mumkin, bu eritmadan chiqqanda uni ushlab qolish mumkin. Qayta qattiq uran tetrafloridga aylantirilgach, uni asosiy tuz muhitiga bo'linishgacha aralashtirish mumkin. Yadroning tuzi ham avvalo tozalanadi florlash uranni olib tashlash uchun, keyin vakuumli distillash tashuvchi tuzlarni olib tashlash va qayta ishlatish uchun. The hali ham keyin qolgan tagliklar distillash LFTR ning bo'linish mahsuloti chiqindilari.

Yadro va adyol suyuqligini ajratishning afzalliklari quyidagilardan iborat:

1. Oddiy yoqilg'ini qayta ishlash. Torium kimyoviy jihatdan bir necha bo'linish mahsulotlariga o'xshaydi lantanoidlar. Torium alohida adyolda, lantanoidlardan ajratilgan holda saqlanadi. Yadro suyuqligidagi toriumsiz lantanid bo'linish mahsulotlarini olib tashlash soddalashtirilgan.
2. Fissile inventarizatsiyasi past. Bo'linadigan yoqilg'i kichik yadroli suyuqlikda kontsentrlanganligi sababli reaktor yadrosi yanada ixchamdir. Tashqi adyolda naslchilik uchun unumdor yoqilg'ini o'z ichiga oladigan bo'linadigan material yo'q, u erda etishtirilgan. Shu sababli, 1968 yil ORNL dizayni uchun 250 MVt (e) ikkita suyuq MSBR reaktorini ishga tushirish uchun atigi 315 kilogramm bo'linuvchi materiallar kerak edi.^[24](p35) Bu dastlabki bo'linishni boshlash zaryadining narxini pasaytiradi va har qanday bo'linadigan materialga ko'proq reaktorlarni ishga tushirishga imkon beradi.
3. Ko'proq samarali naslchilik. Torium adyol yadro mintaqasidan chiqib ketgan neytronlarni samarali ravishda ushlab turishi mumkin. Adyolda deyarli nolga bo'linish mavjud, shuning uchun adyolning o'zi juda ko'p miqdordagi neytronlarni to'kmaydi. Bu neytronlardan foydalanishning yuqori samaradorligini (neytron iqtisodiyoti) va naslchilik koeffitsientini yuqori bo'lishiga olib keladi, ayniqsa kichik reaktorlarda.

Ikkala suyuqlik konstruktsiyasining bitta zaif tomoni shundaki, neytronning tez shikastlanishi sababli vaqti-vaqti bilan yadro-adyol to'sig'ini almashtirish zarur.^[25](p29) ORNL o'zining pastligi sababli to'siq materiallari uchun grafitni tanladi neytronning yutilishi, eritilgan tuzlar bilan mosligi, yuqori haroratga chidamliligi va yonilg'i va adyol tuzlarini ajratish uchun etarli kuch va yaxlitlik. Neytron nurlanishining grafitga ta'siri asta-sekin kichrayib, keyin shishib, g'ovaklikning oshishiga va fizikaviy xususiyatlarning yomonlashishiga olib keladi.^[24](p13) Grafit quvurlari uzunligini o'zgartiradi va yorilib oqishi mumkin.

Ikki suyuqlikli dizaynning yana bir zaifligi uning murakkab sanitariya-tesisatidir. ORNL yadro va adyol naychalarining murakkab o'zaro tutilishi yuqori quvvat zichligiga erishish uchun yuqori quvvat darajasiga erishish uchun zarur deb o'ylardi.^[24](p4) ORNL ikkita suyuqlik konstruktsiyasini ta'qib qilmaslikni tanladi va hech qachon ikkita suyuqlik reaktori namunalari bunyod etilmadi.

Shu bilan birga, yaqinda o'tkazilgan tadqiqotlar ORNL-ning murakkab qatlamli grafitli trubkalariga ehtiyoj tug'dirdi va murakkab quvurlarsiz yuqori quvvat ishlab chiqarishga imkon beradigan, termal kengayishni ta'minlaydigan va trubkani almashtirishga imkon beradigan oddiy cho'zilgan trubkali reaktorni taklif qildi.^[1](p6) Bundan tashqari, grafitni yuqori molibden qotishmalari bilan almashtirish mumkin sintezlash tajribalari va neytronlarning shikastlanishiga nisbatan ko'proq bardoshlikga ega.^[1](p6)

Gibrid "bir yarim suyuqlik" reaktori

Yoqilg'i tuzida tori bo'lgan ikkita suyuq reaktor ba'zan "bir yarim suyuqlik" yoki 1,5 suyuq reaktor deb ataladi.^[26] Bu gibrid bo'lib, unda 1 ta suyuqlik va 2 ta suyuq reaktorning ba'zi afzalliklari va kamchiliklari mavjud. 1 ta suyuq reaktor singari yoqilg'i tuzida tori bor, bu esa yoqilg'ini qayta ishlashni murakkablashtiradi. Va shunga qaramay, 2 ta suyuqlik reaktori singari, yadrodan oqib chiqadigan neytronlarni yutish uchun yuqori samarali alohida adyoldan foydalanishi mumkin. To'siq yordamida suyuqliklarni bir-biridan ajratib turishning qo'shimcha kamchiliklari saqlanib qoladi, ammo torium yonilg'i tuzida bu to'siqdan adyol suyuqligiga o'tishi kerak bo'lgan kamroq neytronlar mavjud. Bu to'siqni kamroq shikastlanishiga olib keladi. To'siqdagi har qanday qochqinning oqibati pastroq bo'ladi, chunki protsessing tizimi allaqachon yadrodagi torium bilan shug'ullanishi kerak.

Bir yarim yoki ikkita suyuq LFTR o'rtasida qaror qabul qilishda dizayndagi asosiy savol - bu murakkabroq qayta ishlash yoki talabchan strukturaviy to'siqni hal qilish osonroq bo'ladimi.

Elektr energiyasini ishlab chiqarish

Ishlash harorati 700 daraja Selsiy bo'lgan LFTR a da ishlashi mumkin issiqlik samaradorligi 45% issiqlik energiyasini elektr energiyasiga aylantirishda.^[23] Bu hozirgi elektr energiyasidan 32-36% gacha bo'lgan engil suv reaktorlaridan yuqori (LWR). elektr energiyasini ishlab chiqarish, jamlangan issiqlik energiyasi yuqori haroratli LFTR dan yuqori darajadagi sanoat jarayoni issiqlik sifatida foydalanish mumkin, masalan, ko'plab foydalanish uchun ammiak bilan ishlab chiqarish Xabar jarayoni yoki termal Vodorod ishlab chiqarish birinchi navbatda elektr energiyasiga aylantirish samaradorligini yo'qotishini yo'q qilish, suvning bo'linishi bilan.

Rankin tsikli

Rankin bug 'aylanishi

Rankin tsikli eng asosiy termodinamik quvvat aylanishi hisoblanadi. Eng oddiy tsikl a dan iborat bug 'generatori, turbin, kondensator va nasos. Ishlaydigan suyuqlik odatda suvdir. LFTR bilan birlashtirilgan Rankine quvvatini konversiyalash tizimi uni yaxshilash uchun bug 'haroratining ko'tarilishidan foydalanishi mumkin issiqlik samaradorligi.^[27] Subkritik Rankin bug 'tsikli hozirgi vaqtda tijorat elektr stantsiyalarida qo'llanilmoqda, eng yangi zavodlar yuqori harorat, yuqori bosim va superkritik Rankin bug' davrlarini ishlatmoqda. 1960-70-yillarda MSBR-da ORNL-ning ishi 44% samaradorlik bilan standart superkritik bug 'turbinasidan foydalanishni o'z zimmasiga oldi.^[25](p74) va eritilgan ftorli tuz - bug 'generatorlarini yaratish bo'yicha katta loyihalash ishlarini olib bordilar.^[28]

Brayton sikli

Yopiq tsiklli gaz turbinasi sxematik

The Brayton sikli generator Rankine tsiklidan ancha kichikroq izga ega, arzonroq va yuqori issiqlik samaradorligi, ammo yuqori ish haroratini talab qiladi. Shuning uchun u LFTR bilan ishlash uchun juda mos keladi. Ishlaydigan gaz geliy, azot yoki karbonat angidrid bo'lishi mumkin. Yuqori bosimli ishlaydigan gaz turbinada kengaytirilib, quvvat ishlab chiqaradi. Past bosimli iliq gaz atrof-muhit sovutgichida sovutiladi. Past bosimli sovuq gaz tizimning yuqori bosimiga siqiladi. Ko'pincha turbin va kompressor bitta o'q orqali mexanik ravishda ulanadi.^[29] Yuqori bosimdagi Brayton tsikllari pastroq Rankin tsikllariga nisbatan kichikroq generator iziga ega bo'lishi kutilmoqda. Brayton tsikli issiqlik dvigateli kengroq diametrli quvurlar bilan pastroq bosim ostida ishlashi mumkin.^[29] Dunyodagi birinchi reklama roligi Brayton sikli quyosh energiyasi moduli (100 kVt) 2009 yilda Isroilning Arava cho'lida qurilgan va namoyish qilingan.^[30]

Bo'linish mahsulotlarini olib tashlash

Ushbu bo'lim aksariyat o'quvchilar tushunishi uchun juda texnik bo'lishi mumkin. Iltimos uni yaxshilashga yordam bering ga buni mutaxassis bo'lmaganlarga tushunarli qilish, texnik ma'lumotlarni olib tashlamasdan. (2015 yil aprel) (Ushbu shablon xabarini qanday va qachon olib tashlashni bilib oling)

LFTR ga parchalanish mahsulotlarini yoqilg'idan olib tashlash mexanizmi kerak, reaktorda qolgan parchalanish mahsulotlari neytronlarni yutadi va shu bilan kamaytiradi neytron iqtisodiyoti. Bu toriy yoqilg'isi aylanishida oz miqdordagi zaxira neytronlar va emilim kuchli bo'lgan termal neytronlar spektri bilan juda muhimdir.Minimal talab ishlatilgan yoqilg'idan qimmatbaho bo'linadigan materialni olishdir.

Parchalanish mahsulotlarini olib tashlash qattiq yoqilg'i elementlarini qayta ishlashga o'xshaydi; kimyoviy yoki fizik vositalar bilan qimmatbaho bo'linadigan yoqilg'i chiqindilarni ajratish mahsulotlaridan ajratib olinadi. Ideal holda unumdor yoqilg'i (torium yoki U-238) va boshqa yoqilg'i komponentlari (masalan, tashuvchi tuz yoki qattiq yoqilg'ida yoqilg'i qoplamasi) yangi yoqilg'i uchun qayta ishlatilishi mumkin. Biroq, iqtisodiy sabablarga ko'ra ular chiqindilar bilan yakunlanishi mumkin.

Joyda ishlov berish doimiy ravishda, har kuni tuzning ozgina qismini tozalash va reaktorga yuborish bilan davom etishi rejalashtirilgan. Yoqilg'i tuzini juda toza qilishning hojati yo'q; maqsadi parchalanadigan mahsulotlar va boshqa aralashmalar (masalan, kislorod) kontsentratsiyasini etarlicha past darajada ushlab turishdir. Ba'zi noyob tuproq elementlarining kontsentratsiyasi ayniqsa past bo'lishi kerak, chunki ular assimilyatsiya kesimiga ega. Kabi kichik tasavvurga ega bo'lgan ba'zi boshqa elementlar CS yoki Zr Ular olib tashlanmasdan oldin ko'p yillar davomida to'planishi mumkin.

LFTR yoqilg'isi eritilgan tuz aralashmasi bo'lgani uchun uni ishlatish jozibador pirroprotsessing, to'g'ridan-to'g'ri issiq eritilgan tuz bilan ishlaydigan yuqori haroratli usullar. Piroprosessiya radiatsiyaga sezgir bo'lgan erituvchilardan foydalanmaydi va ularni parchalanish issiqligi osonlikcha bezovta qilmaydi. Uni to'g'ridan-to'g'ri reaktordan yuqori radioaktiv yoqilg'ida ishlatish mumkin.^[31]Reaktorga yaqin joyda kimyoviy ajratishni amalga oshirish transportni oldini oladi va yonilg'i aylanishining umumiy zaxirasini past darajada ushlab turadi. Yangi yoqilg'i (torium) va chiqindilar (bo'linish mahsulotlari) dan tashqari hamma narsa zavod ichida qoladi.

Suyuq yoqilg'ining potentsial afzalliklaridan biri shundaki, u nafaqat bo'linish mahsulotlarini yoqilg'idan ajratib olishni osonlashtiradi, balki alohida bo'linadigan mahsulotlarni bir-biridan ajratib turadi, bu esa kam bo'lgan va turli xil sanoat (radiatsiya manbalari) uchun talab yuqori bo'lgan izotoplar uchun foydali bo'ladi. payvand choklarini rentgenografiya yordamida tekshirish uchun), qishloq xo'jaligi (nurlanish orqali mahsulotni sterilizatsiya qilish) va tibbiy maqsadlarda foydalanish (Molibden-99 bu parchalanadi Technetium-99m, qimmatbaho radioelement tibbiy tekshiruvlarda saraton hujayralarini belgilash uchun bo'yoq).

Element guruhi bo'yicha tafsilotlar

Ko'proq olijanob metallar (Pd, Ru, Ag, Mo, Nb, Sb, Kompyuter ) oddiy tuzda ftoridlar hosil qilmang, aksincha yaxshi kolloid metall zarralar. Ular issiqlik almashinuvchisi kabi metall yuzalarga yoki tercihen almashtirish osonroq bo'lgan yuqori sirt filtrlariga joylashtirilishi mumkin. Shunga qaramay, ularning tugashi bilan bog'liq ba'zi bir noaniqliklar mavjud, chunki MSRE faqat nisbatan qisqa operatsion tajribani taqdim etdi va mustaqil laboratoriya tajribalari qiyin.^[32]

Gazlar yoqadi Xe va Kr a bilan osongina chiqing siyrak geliy. Bundan tashqari, ba'zi "olijanob" metallarni an aerozol. Tez olib tashlash Xe-135 ayniqsa juda muhimdir, chunki bu juda kuchli neytron zahari va olib tashlanmasa, reaktor nazoratini qiyinlashtiradi; bu neytron iqtisodiyotini yaxshilaydi. Gaz (asosan He, Xe va Kr) deyarli barcha Xe-135 va boshqa qisqa muddatli izotoplar parchalanmaguncha taxminan 2 kun saqlanadi. Keyinchalik gazning katta qismini qayta ishlash mumkin. Bir necha oy qo'shimcha ushlab turilgandan so'ng, radioaktivlik past haroratlarda gazni geliy (qayta ishlatish uchun), ksenon (sotish uchun) va kriptonga ajratish uchun etarlicha past bo'ladi, bu uzoq vaqt davomida saqlashga (masalan, siqilgan holda) muhtoj (bir necha marta) parchalanishini kutish Kr-85.^[18](p274)

Tuz aralashmasini tozalash uchun kimyoviy ajratishning bir necha usullari taklif qilingan.^[33]Klassik bilan taqqoslaganda PUREX qayta ishlash, pirroprotsessing yanada ixcham bo'lishi va kamroq ikkilamchi chiqindilarni chiqarishi mumkin. LFTR tuzining pirroprotsesslari allaqachon mos suyuqlik shaklidan boshlanadi, shuning uchun qattiq oksidli yoqilg'idan arzonroq bo'lishi mumkin, ammo to'liq eritilgan tuzni qayta ishlash zavodi qurilmaganligi sababli barcha sinovlar laboratoriya bilan cheklangan va faqat bir nechta elementlar. Ajratishni yaxshilash va qayta ishlashni iqtisodiy jihatdan foydali qilish uchun hali ham ko'proq tadqiqotlar va ishlanmalar mavjud.

Uran va boshqa ba'zi elementlarni ftorning o'zgaruvchanligi deb ataladigan jarayon yordamida tuzdan tozalash mumkin: A siyrak ning ftor uchuvchan yuqorivalentlik ftoridlar gaz sifatida. Bu asosan uran geksaflorid tarkibida uran-233 yoqilg'isi ham mavjud neptuniy geksaflorid, texnikum geksaflorid va selenyum geksaflorid, shuningdek, boshqalarning floridlari bo'linish mahsulotlari (masalan, yod, molibden va tellur). Uchuvchi ftoridlarni adsorbsiya va distillash bilan ajratish mumkin. Uxan heksaflorid bilan ishlash boyitishda yaxshi tasdiqlangan. Yuqori valentli ftoridlar yuqori haroratlarda juda korroziydir va Xastelloyga qaraganda ancha chidamli materiallarni talab qiladi. ORNL-da MSBR dasturining bitta taklifi qattiq qatlamdan himoya qatlami sifatida foydalanish edi. MSRE reaktorida uranni yoqilg'i tuzidan tozalash uchun ftor uchuvchanligi ishlatilgan. Qattiq yoqilg'i elementlari bilan ishlatish uchun ftorning o'zgaruvchanligi juda yaxshi ishlab chiqilgan va sinovdan o'tgan.^[31]

MSRE dasturi davomida sinovdan o'tgan yana bir oddiy usul bu yuqori haroratli vakuum distillashidir. Uran tetraflorid va LiF va BeF tashuvchisi tuzi kabi quyi qaynash temperaturasidagi ftoridlarni distillash orqali yo'q qilish mumkin. Vakuum ostida harorat atrof-muhit bosimining qaynash nuqtasidan past bo'lishi mumkin. Shunday qilib, taxminan 1000 ° C harorat FLiBe tashuvchisi tuzining ko'p qismini tiklash uchun etarli.^[34] Ammo, printsipial jihatdan, torium floridni undan yuqori qaynoq nuqtasidan lantanid ftoridlaridan ajratish juda yuqori harorat va yangi materiallarni talab qiladi. 2-suyuqlik konstruktsiyalari uchun kimyoviy ajratish, uranni bo'linuvchi yoqilg'i sifatida ishlatish, bu ikkitasi bilan nisbatan ishlashi mumkin oddiy jarayonlar:^[35]Adyol tuzidan uranni ftor uchuvchanligi bilan olib tashlash mumkin va uni yadro tuziga o'tkazish mumkin. Parchalanuvchi mahsulotlarni yadro tuzidan olib tashlash uchun avval uran ftorning o'zgaruvchanligi bilan tozalanadi. Keyin tashuvchi tuzni yuqori haroratli distillash yordamida tiklash mumkin. Qaynash harorati yuqori bo'lgan ftoridlar, shu jumladan lantanidlar chiqindilar sifatida qoladi.

Ixtiyoriy protaktinium-233 ajralishi

Dastlabki Oak Ridge-ning kimyoviy dizaynlari ko'payish bilan bog'liq bo'lmagan va tez naslga yo'naltirilgan. Ular ajratishni va saqlashni rejalashtirishgan protaktinium-233, shuning uchun u reaktorda neytron tutilishi natijasida yo'q qilinmasdan uran-233 ga parchalanishi mumkin. Yarim umr 27 kun bo'lganida, 2 oylik saqlash 75% ni ta'minlaydi ²³³Pa parchalanadi ²³³U yoqilg'i. LFTR uchun protaktiniumni olib tashlash bosqichi talab qilinmaydi. Muqobil echimlar kuchning past zichligida ishlaydi va shu bilan katta bo'linadigan inventarizatsiya (1 yoki 1,5 suyuqlik uchun) yoki kattaroq adyol (2 suyuqlik uchun). Bundan tashqari, qattiqroq neytronlar spektri protaktinium izolyatsiyasiz maqbul naslga erishishga yordam beradi.^[1]

Agar Pa ajratish ko'rsatilgan bo'lsa, samarali bo'lishi uchun buni tez-tez (masalan, har 10 kunda) bajarish kerak. 1 GVt quvvatga ega 1 suyuqlikli zavod uchun bu yoqilg'ining taxminan 10% yoki 15 tonna yoqilg'i tuzining har kuni qayta ishlashga to'g'ri kelishini anglatadi. Bu faqat qattiq yoqilg'ini qayta ishlashga sarflanadigan xarajatlardan ancha past bo'lgan taqdirda amalga oshiriladi.

Yangi dizaynlar odatda Pa-ni olib tashlashdan qochishadi^[1] va qayta ishlashga kamroq tuz yuboring, bu esa kimyoviy ajratish uchun kerakli hajm va xarajatlarni kamaytiradi. Shuningdek, u kimyoviy jihatdan ajratilgan Pa parchalanishidan kelib chiqishi mumkin bo'lgan yuqori tozaligi U-233 tufayli ko'payish xavotiridan saqlaydi.

Bo'linish mahsulotlari torium bilan aralashtirilsa, ajratish qiyinroq kechadi, chunki torium, plutoniy va lantanoidlar (noyob tuproq elementlari) kimyoviy jihatdan o'xshashdir. Protactiniumni ajratish va lantanidlarni olib tashlash uchun tavsiya etilgan jarayonlardan biri bu eritilgan bilan aloqa qilishdir vismut. A oksidlanish-qaytarilish - reaksiya ba'zi metallarni bizmut eritmasiga qo'shilgan lityum evaziga vismut eritmasiga o'tkazish mumkin. Lityumning past konsentratsiyalarida U, Pu va Pa vismut eritmalariga o'tadi. Ko'proq qisqarish sharoitida (vismut tarkibida ko'proq lityum) lantanoidlar va tori vismutga ham o'tadi. Keyin bo'linish mahsulotlari alohida bosqichda vismut qotishmasidan chiqariladi, masalan. LiCl eritmasi bilan aloqa qilish orqali.^[36] Ammo bu usul juda kam rivojlangan. Xuddi shunday usul alyuminiy kabi boshqa suyuq metallarda ham mumkin bo'lishi mumkin.^[37]

Afzalliklari

Torium bilan ishlaydigan eritilgan tuz reaktorlari odatdagi qattiq uran bilan ishlaydigan engil suvli reaktorlarga nisbatan juda ko'p afzalliklarga ega:^{[8][20][38][39][40][41]}

Xavfsizlik

• Tabiiy xavfsizlik. LFTR dizaynlarida kuchli ishlatiladi reaktivlikning salbiy harorat koeffitsienti passivga erishish tabiiy xavfsizlik reaktivlikning ekskursiyalariga qarshi. Haroratga bog'liqlik 3 manbadan kelib chiqadi. Birinchisi, torium haddan tashqari qizib ketsa, ko'proq Dopler effekti deb ataladigan ko'proq neytronlarni yutadi.^[42] Bu zanjir reaktsiyasini davom ettirish uchun kamroq neytronlarni qoldirib, quvvatni pasaytiradi. Ikkinchi qism grafit moderatorini isitadi, bu odatda harorat koeffitsientiga ijobiy hissa qo'shadi.^[42] Uchinchi effekt bilan bog'liq issiqlik kengayishi yoqilg'ining.^[42] Agar yoqilg'i qizib ketsa, u sezilarli darajada kengayadi, bu yoqilg'ining suyuqligi sababli yoqilg'ini faol yadro mintaqasidan chiqarib yuboradi. Kichik (masalan, MSRE sinov reaktori) yoki yaxshi mo''tadil yadroda bu reaktivlikni pasaytiradi. Shu bilan birga, moderatsiya darajasi katta bo'lmagan yadroda (masalan, ORNL MSBR dizayni) kamroq yoqilg'i tuzi yaxshi moderatsiyani va shuning uchun ko'proq reaktivlikni va kiruvchi ijobiy harorat koeffitsientini anglatadi.
• Barqaror sovutish suyuqligi. Eritilgan ftoridlar kimyoviy jihatdan barqaror va nurlanish o'tkazmaydi. Tuzlar yuqori harorat va nurlanish ostida ham yonmaydi, portlamaydi yoki parchalanmaydi.^[43] Natriy sovutish suvi bo'lgan suv va havo bilan tezkor zo'ravonlik reaktsiyalari mavjud emas. Suv sovutgichlarida mavjud bo'lgan yonuvchan vodorod ishlab chiqarish yo'q.^[44] Ammo tuz tufayli past (100 C dan past) haroratlarda nurlanish barqaror emas radioliz.
• Past bosimli ishlash. Sovutish suyuqligi tuzlari yuqori haroratda suyuq bo'lib qolishi sababli,^[43] LFTR yadrolari 0,6 MPa kabi past bosimlarda ishlashga mo'ljallangan^[45] (ichimlik suvi tizimidagi bosim bilan solishtirish mumkin) nasosdan va gidrostatik bosimdan. Hatto yadro ishlamay qolsa ham^{[tushuntirish kerak ]}, hajmning ozgina o'sishi kuzatilmoqda. Shunday qilib qamoqxona binosi portlay olmaydi. LFTR sovutish suyuqligi tuzlari qaynash harorati juda yuqori bo'lganligi uchun tanlangan. Vaqtinchalik yoki baxtsiz hodisa paytida bir necha yuz daraja issiqlik ham bosimning sezilarli darajada oshishiga olib kelmaydi. Reaktorda katta bosim ko'tarilishiga yoki portlashga olib keladigan suv yoki vodorod yo'q Fukushima Daiichi yadroviy halokati.^{[46][ishonchli manba ]}
• Bo'linish natijasida bosim kuchaymaydi. LFTR'lar gazsimon va o'zgaruvchan bo'linish mahsulotlari. Suyuq yoqilg'i ksenon kabi gazsimon bo'linadigan mahsulotlarni qayta ishlash uchun onlayn ravishda olib tashlashga imkon beradi, shuning uchun bu parchalanadigan mahsulotlar falokat paytida tarqalmaydi.^[47] Bundan tashqari, bo'linish mahsulotlari kimyoviy jihatdan ftorli tuz bilan, shu jumladan yod bilan,^{[shubhali – muhokama qilish]} radiatsiyani ushlab turuvchi va radioaktiv moddalarning atrofga tarqalishini oldini oladigan seziy va stronsiyum.^[48]
• Nazorat qilish osonroq. Eritilgan yonilg'i reaktori ksenon-135ni oson olib tashlashning afzalliklariga ega. Ksenon-135, muhim neytron yutuvchi, qattiq yonilg'i bilan ishlaydigan reaktorlarni boshqarishni qiyinlashtiradi. Eritilgan yonilg'i bilan ishlaydigan reaktorda ksenon-135 o'chirilishi mumkin. Qattiq yonilg'i reaktorlarida xenon-135 yoqilg'ida qoladi va reaktorni boshqarishga xalaqit beradi.^[49]
• Sekin qizish. Sovutish moslamasi va yoqilg'ini ajratib bo'lmaydi, shuning uchun har qanday oqish yoki yoqilg'ining harakatlanishi tabiiy ravishda katta miqdorda sovutish suyuqligi bilan birga bo'ladi. Eritilgan ftoridlarning miqdori yuqori hajmli issiqlik quvvati, ba'zilari kabi FLiBe, hatto suvdan ham balandroq. Bu ularga vaqtinchalik yoki baxtsiz hodisalar paytida katta miqdordagi issiqlikni singdirishga imkon beradi.^[33][50]
• Passiv parchalanish issiqlik sovutish. Ko'p reaktor dizayni (masalan, Eritilgan-tuzli reaktor tajribasi ) reaktor ishlamay turganda, yonilg'i / sovutish suvi aralashmasining drenaj idishiga tushishiga imkon bering (quyida "Xato xavfsiz yadro" ga qarang). Ushbu tankda passiv parchalanish issiqligini yo'q qilishning biron bir turi (tafsilotlar hali ham ochiq) bo'lishi rejalashtirilgan, shuning uchun ishlash uchun fizik xususiyatlarga (boshqarish o'rniga).^[51]
• Xavfsiz yadro ishlamayapti. LFTR-lar pastki qismida muzlatish vilkasini o'z ichiga olishi mumkin, uni faol ravishda sovutish kerak, odatda kichik elektr foniy. Agar sovutish ishlamay qolsa, masalan, elektr quvvati uzilishi sababli, fan to'xtaydi, vilka eriydi va yonilg'i quyiladi subkritik passiv sovutilgan saqlash ombori. Bu nafaqat reaktorni to'xtatibgina qolmay, balki saqlash ombori nurlangan yadro yoqilg'ilarining qisqa muddatli radioaktiv parchalanishidan parchalanish issiqligini ham osonroq to'kishi mumkin. Quvur sinishi kabi yadrodan katta qochqin kelib chiqqan taqdirda ham, tuz reaktor joylashgan oshxonadagi lavabo shaklidagi xonaga to'kiladi, bu esa yoqilg'i tuzini tortish kuchi bilan passiv sovutilgan axlatxonaga tushiradi.^[19]
• Kamroq uzoq umr ko'radigan chiqindilar. LFTR uzoq muddatli istiqbolni keskin qisqartirishi mumkin radioksiklik ularning reaktor chiqindilari. Uran yoqilg'isiga ega engil suvli reaktorlarda 95% U-238 dan yuqori yoqilg'i mavjud. Ushbu reaktorlar odatda U-238 ning uzoq muddatli izotopi bo'lgan Pu-239 ga o'tadi. Shuning uchun deyarli barcha yoqilg'i transuranik uzoq umr ko'radigan elementga aylanishdan bir qadam oldinda. Plutonyum-239 a ga ega yarim hayot 24000 yillik va eng keng tarqalgan transuranik yengil suv reaktorlaridan foydalanilgan yadro yoqilg'isida. Pu-239 kabi transuranika reaktor chiqindilari an abadiy muammo. Aksincha, LFTR torium yoqilg'isi aylanishi, bu toriumni U-233 ga o'tkazadi. Torium engilroq element bo'lgani uchun transuranik elementlarni hosil qilish uchun ko'proq neytron ushlash talab etiladi. U-233 LFTRda bo'linish uchun ikkita imkoniyatga ega. Avval U-233 (90% bo'linadi), so'ngra qolgan 10% yana bir imkoniyatga ega, chunki U-235 ga o'tadi (80% bo'linadi). Neptuniy-237 ga yetadigan yoqilg'ining ulushi, ehtimol transuranik element, shuning uchun atigi 2%, GWe yiliga taxminan 15 kg.^[52] Bu GWe yiliga 300 kg transuranika ishlab chiqaradigan engil suvli reaktorlardan 20 baravar kichik transuranik ishlab chiqarish. Muhimi, bu juda kichik transuranik ishlab chiqarish tufayli transuranikani qayta ishlash ancha osonlashadi. Ya'ni, ular oxir-oqibat bo'linish uchun yadroga qaytariladi. U238-plutonyum yonilg'i tsiklida ishlaydigan reaktorlar transuranikani ancha ko'p ishlab chiqaradi, bu reaktor neytronikasida ham, qayta ishlash tizimida ham to'liq qayta ishlashni qiyinlashtiradi. LFTRda foizlarning atigi bir qismi, qayta ishlashni yo'qotish sifatida, oxirgi chiqindilarga ketadi. Pastroq transuranik ishlab chiqarish va qayta ishlashning ushbu ikkita foydasi birlashtirilganda, torium yoqilg'isi aylanishi kamayadi ishlab chiqarish odatdagi uran yoqilg'isi bilan taqqoslaganda transuranik chiqindilar ming baravar ko'p engil suvli reaktor. Faqatgina uzoq umr ko'radigan chiqindilar - bu uran yoqilg'isining o'zi, ammo undan qayta ishlash, doimo elektr energiyasini ishlab chiqarish orqali cheksiz foydalanish mumkin.
  Agar torium pog'onasini yopish kerak bo'lsa, reaktorlarning bir qismi yopilishi va qolgan reaktorlarda uran yoqilg'isi zaxiralari yonib ketishi mumkin, bu hatto bu oxirgi chiqindilarni ham jamiyat talab qilgan darajada kichik darajaga etkazishiga imkon beradi.^[53] LFTR hali ham chiqindilarida radioaktiv parchalanish mahsulotlarini ishlab chiqaradi, ammo ular juda uzoq davom etmaydi - bu bo'linish mahsulotlarining radioksitliligi ustunlik qiladi seziy-137 va stronsiy-90. Yarim umr uzoqroq seziy: 30,17 yil. Shunday qilib, 30.17 yildan keyin parchalanish radioaktivlikni yarimga kamaytiradi. O'n yarim hayot radioaktivlikni ikkitaga kamaytiradi, o'nga teng, 1024 omil. O'sha paytda 300 yil ichida bo'linadigan mahsulotlar tabiiy uranga qaraganda kamroq radioaktivdir.^[54][55] Bundan tashqari, yoqilg'i materialining suyuq holati parchalanish mahsulotlarini nafaqat yoqilg'idan, balki bir-biridan ajratishga imkon beradi, bu esa ularni har bir bo'linish mahsulotining yarim umrining davomiyligi bo'yicha saralashga imkon beradi. yarim umrlari qisqaroq bo'lsa, yarim umrlari uzoqroq bo'lganlarga qaraganda tezroq ombordan chiqarilishi mumkin.
• Ko'payishga qarshilik. 2016 yilda, Nobel mukofoti sovrindori fizik Doktor Karlo Rubbiya, sobiq bosh direktori CERN, Qo'shma Shtatlarning 1970-yillarda torium reaktorini tadqiq qilishini qisqartirishining asosiy sababi shundaki, bugungi kunda uni jozibali qiladi: toriumni aylantirish qiyin yadro quroli.^{[56][ishonchli manba? ]}
  LFTR o'z yoqilg'isini yadro quroliga aylantirishga to'rt xilda qarshi turadi: birinchidan, torium-232 zotlari avval protaktinium-233 ga aylanib, keyinchalik uran-233 ga aylanadi. Agar protaktiniy reaktorda qolsa, oz miqdordagi U-232 ham ishlab chiqariladi. U-232 kuchli, xavfli gamma nurlarini chiqaradigan parchalanish zanjiri mahsulotiga (talliy-208) ega. Bular reaktor ichidagi muammo emas, lekin bomba tarkibida ular bomba ishlab chiqarishni murakkablashtiradi, elektronikaga zarar etkazadi va bomba joylashgan joyni ochib beradi.^[57] Ikkinchi tarqalishga chidamli xususiyati shundaki, LFTRlar juda oz miqdordagi plutonyum ishlab chiqaradi, yiliga bir gigavatt elektr energiyasi uchun 15 kg atrofida (bu bir yil davomida bitta katta reaktorning chiqishi). This plutonium is also mostly Pu-238, which makes it unsuitable for fission bomb building, due to the high heat and spontaneous neutrons emitted. The third track, a LFTR doesn't make much spare fuel. It produces at most 9% more fuel than it burns each year, and it's even easier to design a reactor that makes only 1% more fuel. With this kind of reactor, building bombs quickly will take power plants out of operation, and this is an easy indication of national intentions. And finally, use of thorium can reduce and eventually eliminate the need to enrich uranium. Uranium enrichment is one of the two primary methods by which states have obtained bomb making materials.^[8]

Economy and efficiency

Comparison of annual fuel requirements and waste products of a 1 GW uranium-fueled LWR and 1 GW thorium-fueled LFTR power plant.^[58]

• Thorium abundance. A LFTR breeds thorium into uranium-233 fuel. The Earth's crust contains about three to four times as much thorium as U-238 (thorium is about as abundant as qo'rg'oshin ). It is a byproduct of rare-earth mining, normally discarded as waste. Using LFTRs, there is enough affordable thorium to satisfy the global energy needs for hundreds of thousands of years.^[59] Thorium is more common in the earth's crust than tin, mercury, or silver.^[8] A cubic meter of average crust yields the equivalent of about four sugar cubes of thorium, enough to supply the energy needs of one person for more than ten years if completely fissioned.^[8] Lemhi dovoni ustida Montana -Aydaho border is estimated to contain 1,800,000 tons of high-grade thorium ore.^[8] Five hundred tons could supply all U.S. energy needs for one year.^[8] Due to lack of current demand, the U.S. government has returned about 3,200 metric tons of refined thorium nitrate to the crust, burying it in the Nevada desert.^[8]
• No shortage of natural resources. Sufficient other natural resources such as beryllium, lithium, nickel and molybdenum are available to build thousands of LFTRs.^[60]
• Reactor efficiency. Conventional reactors consume less than one percent of the mined uranium, leaving the rest as waste. With perfectly working reprocessing LFTR may consume up to about 99% of its thorium fuel. The improved fuel efficiency means that 1 ton of natural thorium in a LFTR produces as much energy as 35 t of enriched uranium in conventional reactors (requiring 250 t of natural uranium),^[8] or 4,166,000 tons of black coal in a coal power plant.
• Thermodynamic efficiency. LFTRs operating with modern supercritical steam turbines would operate at 45% thermal to electrical efficiency. With future closed gas Brayton cycles, which could be used in a LFTR power plant due to its high temperature operation, the efficiency could be up to 54%. This is 20 to 40% higher than today's light water reactors (33%), resulting in the same 20 to 40% reduction in fissile and fertile fuel consumption, fission products produced, waste heat rejection for cooling, and reactor thermal power.^[8]
• No enrichment and fuel element fabrication. Since 100% of natural thorium can be used as a fuel, and the fuel is in the form of a molten salt instead of solid fuel rods, expensive fuel enrichment and solid fuel rods' validation procedures and fabricating processes are not needed. This greatly decreases LFTR fuel costs. Even if the LFTR is started up on enriched uranium, it only needs this enrichment once just to get started. After startup, no further enrichment is required.^[8]
• Lower fuel cost. The salts are fairly inexpensive compared to solid fuel production. For example, while beryllium is quite expensive per kg, the amount of beryllium required for a large 1 GWe reactor is quite small. ORNL's MSBR required 5.1 tons of beryllium metal, as 26 tons of BeF₂.^[60] At a price of $147/kg BeF₂,^[50](p44) this inventory would cost less than $4 million, a modest cost for a multibillion-dollar power plant. Consequently, a beryllium price increase over the level assumed here has little effect in the total cost of the power plant. The cost of enriched lithium-7 is less certain, at $120–800/kg LiF.^[1] and an inventory (again based on the MSBR system) of 17.9 tons lithium-7 as 66.5 tons LiF^[60] makes between $8 million and $53 million for the LiF. Adding the 99.1 tons of thorium at $30/kg adds only $3 million. Fissile material is more expensive, especially if expensively reprocessed plutonium is used, at a cost of $100 per gram fissile plutonium. With a startup fissile charge of only 1.5 tons, made possible through the soft neutron spectrum^[1] this makes $150 million. Adding everything up brings the total cost of the one time fuel charge at $165 to $210 million. This is similar to the cost of a first core for a light water reactor.^[61] Depending on the details of reprocessing the salt inventory once can last for decades, whereas the LWR needs a completely new core every 4 to 6 years (1/3 is replaced every 12 to 24 months). ORNL's own estimate for the total salt cost of even the more expensive 3 loop system was around $30 million, which is less than $100 million in today's money.^[62]
• LFTRs are cleaner: as a fully recycling system, the discharge wastes from a LFTR are predominantly fission products, most of which (83%) have relatively short half lives in hours or days^[63] compared to longer-lived actinide wastes of conventional nuclear power plants.^[57] This results in a significant reduction in the needed waste containment period in a geologic repository. The remaining 17% of waste products require only 300 years until reaching background levels.^[63] The radiotoxicity of the thorium fuel cycle waste is about 10,000 times less than that of one through uranium fuel.^[8]
• Less fissile fuel needed. Because LFTRs are thermal spectrum reactors, they need much less fissile fuel to get started. Only 1–2 tons of fissile are required to start up a single fluid LFTR, and potentially as low as 0.4 ton for a two fluid design.^[1] In comparison, solid fueled fast breeder reactors need at least 8 tons of fissile fuel to start the reactor. While fast reactors can theoretically start up very well on the transuranic waste, their high fissile fuel startup makes this very expensive.^{[iqtibos kerak ]}
• No downtime for refueling. LFTRs have liquid fuels, and therefore there is no need to shut down and take apart the reactor just to refuel it. LFTRs can thus refuel without causing a power outage (online refueling ).
• Load following. As the LFTR does not have xenon poisoning, there is no problem reducing the power in times of low demand for electricity and turn back on at any time.
• No high pressure vessel. Since the core is not pressurized, it does not need the most expensive item in a light water reactor, a high-pressure reactor vessel for the core. Instead, there is a low-pressure vessel and pipes (for molten salt) constructed of relatively thin materials. Although the metal is an exotic nickel alloy that resists heat and corrosion, Xastelloy -N, the amount needed is relatively small.
• Excellent heat transfer. Liquid fluoride salts, especially LiF based salts, have good heat transfer properties. Fuel salt such as LiF-ThF₄ bor volumetric heat capacity that is around 22% higher than water,^[64] FLiBe has around 12% higher heat capacity than water. In addition, the LiF based salts have a issiqlik o'tkazuvchanligi around twice that of the hot pressurized water in a pressurized water reactor.^[33][50] This results in efficient heat transfer and a compact primary loop. Ga solishtirganda geliy, a competing high temperature reactor coolant, the difference is even bigger. The fuel salt has over 200 times higher volumetric heat capacity as hot pressurized helium and over 3 times the thermal conductivity. A molten salt loop will use piping of 1/5 the diameter, and pumps 1/20 the power, of those required for high-pressure helium, while staying at atmospheric pressure^[65]
• Smaller, low pressure containment. By using liquid salt as the coolant instead of pressurized water, a containment structure only slightly bigger than the reactor vessel can be used. Light water reactors use pressurized water, which flashes to steam and expands a thousandfold in the case of a leak, necessitating a containment building a thousandfold bigger in volume than the reactor vessel. The LFTR containment can not only be smaller in physical size, its containment is also inherently low pressure. There are no sources of stored energy that could cause a rapid pressure rise (such as Hydrogen or steam) in the containment.^{[46][ishonchli manba ]} This gives the LFTR a substantial theoretical advantage not only in terms of inherent safety, but also in terms of smaller size, lower materials use, and lower construction cost.^[8]
• Air cooling. A high temperature power cycle can be air-cooled at little loss in efficiency,^[66] which is critical for use in many regions where water is scarce. No need for large water cooling towers used in conventional steam-powered systems would also decrease power plant construction costs.^[41][67]
• From waste to resource. There are suggestions that it might be possible to extract some of the fission products so that they have separate commercial value.^[68] However, compared to the produced energy, the value of the fission products is low, and chemical purification is expensive.^[69]
• Efficient mining. The extraction process of thorium from the earth's crust is a much safer and efficient mining method than that of uranium. Thorium's ore, monazite, generally contains higher concentrations of thorium than the percentage of uranium found in its respective ore. Bu toriumni tejamkor va ekologik jihatdan kam yonilg'i manbaiga aylantiradi. Thorium mining is also easier and less dangerous than uranium mining, as the mine is an open pit, which doesn't require ventilation such as the underground uranium mines, where radon levels are potentially harmful.^[70]

Kamchiliklari

LFTRs are quite unlike today's operating commercial power reactors. These differences create design difficulties and trade-offs:

• Questionable economics – although proponents of LFTR technology list a wide variety of claimed economic advantages, a 2014 study of their economics from University of Chicago concluded there is no real advantage in overall terms. A number of the claims, like the ambient pressure operation and high-temperature cooling loops, are already used on a number of conventional designs and have failed to produce the economic gains claimed. In other cases, there is simply not enough data to justify any conclusion. When the entire development is considered, the report concluded: "... the difference in cost, given the current industry environment, remains insufficient to justify the creation of a new LFTR."^[71]
• Reaching break-even breeding is questionable – While the plans usually call for break-even breeding, it is questionable if this is possible, when other requirements are to be met.^[42] The thorium fuel cycle has very few spare neutrons. Due to limited chemical reprocessing (for economic reasons) and compromises needed to achieve safety requirements like a negative void coefficient too many neutrons may be lost. Old proposed single fluid designs promising breeding performance tend to have an unsafe positive void coefficient and often assume excessive fuel cleaning to be economic viable.^[42]
• Still much development needed – Despite the ARE and MSRE experimental reactors already built in the 1960s, there is still a lot of development needed for the LFTR. This includes most of the chemical separation, (passive) emergency cooling, the tritium barrier, remote operated maintenance, large scale Li-7 production, the high temperature power cycle and more durable materials.
• Startup fuel – Unlike mined uranium, mined thorium does not have a fissile isotope. Thorium reactors breed fissile uranium-233 from thorium, but require a small amount of fissile material for initial start up. There is relatively little of this material available. This raises the problem of how to start the reactors in a short time frame. One option is to produce U-233 in today's solid fueled reactors, then reprocess it out of the solid waste. An LFTR can also be started by other fissile isotopes, enriched uranium or plutonium from reactors or decommissioned bombs. For enriched uranium startup, high enrichment is needed. Decommissioned uranium bombs have enough enrichment, but not enough is available to start many LFTRs. It is difficult to separate plutonium fluoride from lanthanide fission products. One option for a two-fluid reactor is to operate with plutonium or enriched uranium in the fuel salt, breed U-233 in the blanket, and store it instead of returning it to the core. Instead, add plutonium or enriched uranium to continue the chain reaction, similar to today's solid fuel reactors. When enough U-233 is bred, replace the fuel with new fuel, retaining the U-233 for other startups. A similar option exists for a single-fluid reactor operating as a converter. Such a reactor would not reprocess fuel while operating. Instead the reactor would start on plutonium with thorium as the fertile and add plutonium. The plutonium eventually burns out and U-233 is produced in situ. At the end of the reactor fuel life, the spent fuel salt can be reprocessed to recover the bred U-233 to start up new LFTRs.^[72]
• Salts freezing – Fluoride salt mixtures have melting points ranging from 300 to 600 °C (572 to 1,112 °F). The salts, especially those with beryllium fluoride, are very viscous near their freezing point. This requires careful design and freeze protection in the containment and heat exchangers. Freezing must be prevented in normal operation, during transients, and during extended downtime. The primary loop salt contains the decay heat-generating fission products, which help to maintain the required temperature. For the MSBR, ORNL planned on keeping the entire reactor room (the hot cell) at high temperature. This avoided the need for individual electric heater lines on all piping and provided more even heating of the primary loop components.^[18](p311) One "liquid oven" concept developed for molten salt-cooled, solid-fueled reactors employs a separate buffer salt pool containing the entire primary loop.^[73] Because of the high heat capacity and considerable density of the buffer salt, the buffer salt prevents fuel salt freezing and participates in the passive decay heat cooling system, provides radiation shielding and reduces deadweight stresses on primary loop components. This design could also be adopted for LFTRs.^{[iqtibos kerak ]}
• Beryllium toxicity – The proposed salt mixture FLiBe ko'p miqdorda o'z ichiga oladi berilyum, which is toxic to humans (although nowhere near as toxic as the fission products and other radioactives). The salt in the primary cooling loops must be isolated from workers and the environment to prevent beryllium poisoning. This is routinely done in industry.^{[74](pp52–66)} Based on this industrial experience, the added cost of beryllium safety is expected to cost only $0.12/MWh.^[74](p61) After start up, the fission process in the primary fuel salt produces highly radioactive fission products with a high gamma and neutron radiation field. Effective containment is therefore a primary requirement. It is possible to operate instead using lithium fluoride-thorium fluoride evtektik without beryllium, as the French LFTR design, the "TMSR", has chosen.^[75] This comes at the cost of a somewhat higher melting point, but has the additional advantages of simplicity (avoiding BeF
  ₂ in the reprocessing systems), increased solubility for plutonium-trifluoride, reduced tritium production (beryllium produces lithium-6, which in turn produces tritium) and improved heat transfer (BeF
  ₂ increases the viscosity of the salt mixture). Alternative solvents such as the fluorides of sodium, rubidium and zirconium allow lower melting points at a tradeoff in breeding.^[1]
• Loss of delayed neutrons – In order to be predictably controlled, nuclear reactors rely on delayed neutrons. They require additional slowly-evolving neutrons from fission product decay to continue the chain reaction. Because the delayed neutrons evolve slowly, this makes the reactor very controllable. In an LFTR, the presence of fission products in the heat exchanger and piping means a portion of these delayed neutrons are also lost.^[76] They do not participate in the core's critical chain reaction, which in turn means the reactor behaves less gently during changes of flow, power, etc. Approximately up to half of the delayed neutrons can be lost. In practice, it means that the heat exchanger must be compact so that the volume outside the core is as small as possible. The more compact (higher power density) the core is, the more important this issue becomes. Having more fuel outside the core in the heat exchangers also means more of the expensive fissile fuel is needed to start the reactor. This makes a fairly compact heat exchanger an important design requirement for an LFTR.^{[iqtibos kerak ]}
• Chiqindilarni boshqarish – About 83% of the radioactive waste has a half-life in hours or days, with the remaining 17% requiring 300-year storage in geologically stable confinement to reach background levels.^[63] Because some of the fission products, in their fluoride form, are highly water-soluble, fluorides are less suited to long-term storage. Masalan, ftorli seziy has a very high solubility in water. For long term storage, conversion to an insoluble form such as a glass, could be desirable.^{[iqtibos kerak ]}
• Uncertain decommissioning costs – Cleanup of the Molten-Salt Reactor Experiment was about $130 million, for a small 8 MW(th) unit. Much of the high cost was caused by the unexpected evolution of fluorine and uranium hexafluoride from cold fuel salt in storage that ORNL did not defuel and store correctly, but this has now been taken into consideration in MSR design.^[77] In addition, decommissioning costs don't scale strongly with plant size based on previous experience,^[78] and costs are incurred at the end of plant life, so a small per kilowatthour fee is sufficient. For example, a GWe reactor plant produces over 300 billion kWh of electricity over a 40-year lifetime, so a $0.001/kWh decommissioning fee delivers $300 million plus interest at the end of the plant lifetime.^{[iqtibos kerak ]}
• Noble metal buildup – Some radioactive fission products, such as asil metallar, deposit on pipes. Novel equipment, such as nickel-wool sponge cartridges, must be developed to filter and trap the noble metals to prevent build up.^{[iqtibos kerak ]}
• Limited graphite lifetime – Compact designs have a limited lifetime for the graphite moderator and fuel / breeding loop separator. Under the influence of fast neutrons, the graphite first shrinks, then expands indefinitely until it becomes very weak and can crack, creating mechanical problems and causing the graphite to absorb enough fission products to poison the reaction.^[79] The 1960 two-fluid design had an estimated graphite replacement period of four years.^[1](p3) Eliminating graphite from sealed piping was a major incentive to switch to a single-fluid design.^[18](p3) Replacing this large central part requires remotely operated equipment. MSR designs have to arrange for this replacement. In a molten salt reactor, virtually all of the fuel and fission products can be piped to a holding tank. Only a fraction of one percent of the fission products end up in the graphite, primarily due to fission products slamming into the graphite. This makes the graphite surface radioactive, and without recycling/removal of at least the surface layer, creates a fairly bulky waste stream. Removing the surface layer and recycling the remainder of the graphite would solve this issue.^{[asl tadqiqotmi? ]} Several techniques exist to recycle or dispose of nuclear moderator graphite.^[80] Graphite is inert and immobile at low temperatures, so it can be readily stored or buried if required.^[80] At least one design used graphite balls (pebbles) floating in salt, which could be removed and inspected continuously without shutting down the reactor.^[81] Reducing power density increases graphite lifetime.^[82](p10) By comparison, solid-fueled reactors typically replace 1/3 of the fuel elements, including all of the highly radioactive fission products therein, every 12 to 24 months. This is routinely done under a protecting and cooling column layer of water.
• Graphite-caused positive reactivity feedback – When graphite heats up, it increases U-233 fission, causing an undesirable positive feedback.^[42] The LFTR design must avoid certain combinations of graphite and salt and certain core geometries. If this problem is addressed by employing adequate graphite and thus a well-thermalized spectrum, it is difficult to reach break-even breeding.^[42] The alternative of using little or no graphite results in a faster neutron spectrum. This requires a large fissile inventory and radiation damage increases.^[42]
• Limited plutonium solubility – Fluorides of plutonium, americium and curium occur as trifluorides, which means they have three fluorine atoms attached (PuF
  ₃, AmF
  ₃, Smf
  ₃). Such trifluorides have a limited solubility in the FLiBe carrier salt. This complicates startup, especially for a compact design that uses a smaller primary salt inventory. Of course, leaving plutonium carrying wastes out of the startup process is an even better solution, making this a non-issue. Solubility can be increased by operating with less or no beryllium fluoride (which has no solubility for trifluorides) or by operating at a higher temperature^{[iqtibos kerak ]}(as with most other liquids, solubility rises with temperature). A thermal spectrum, lower power density core does not have issues with plutonium solubility.
• Proliferation risk from reprocessing – Effective reprocessing implies a ko'payish xavf. LFTRs could be used to handle plutonium from other reactors as well. However, as stated above, plutonium is chemically difficult to separate from thorium and plutonium cannot be used in bombs if diluted in large amounts of thorium. In addition, the plutonium produced by the thorium fuel cycle is mostly Pu-238, which produces high levels of spontaneous neutrons and decay heat that make it impossible to construct a fission bomb with this isotope alone, and extremely difficult to construct one containing even very small percentages of it. The heat production rate of 567 W/kg^[83] means that a bomb core of this material would continuously produce several kilowatts of heat. The only cooling route is by conduction through the surrounding high explosive layers, which are poor conductors. This creates unmanageably high temperatures that would destroy the assembly. The spontaneous fission rate of 1204 kBq/g^[83] is over twice that of Pu-240. Even very small percentages of this isotope would reduce bomb yield drastically by "predetonation" due to neutrons from spontaneous fission starting the chain reaction causing a "fizzle " rather than an explosion. Reprocessing itself involves automated handling in a fully closed and contained hot cell, which complicates diversion. Compared to today's extraction methods such as PUREX, the pyroprocesses are inaccessible and produce impure fissile materials, often with large amounts of fission product contamination. While not a problem for an automated system, it poses severe difficulties for would-be proliferators.^{[iqtibos kerak ]}
• Proliferation risk from protactinium separation – Compact designs can breed only using rapid separation of protactinium, a proliferation risk, since this potentially gives access to high purity 233-U. This is difficult as the 233-U from these reactors will be contaminated with 232-U, a high gamma radiation emitter, requiring a protective hot enrichment facility^[63] as a possible path to qurol-yarog ' material. Because of this, commercial power reactors may have to be designed without separation. In practice, this means either not breeding, or operating at a lower power density. A two-fluid design might operate with a bigger blanket and keep the high power density core (which has no thorium and therefore no protactinium).^{[iqtibos kerak ]} However, a group of nuclear engineers argues in Tabiat (2012) that the protactinium pathway is feasible and that thorium is thus "not as benign as has been suggested . . ."^[84]
• Proliferation of neptunium-237 – In designs utilizing a fluorinator, Np-237 appears with uranium as gaseous hexafluoride and can be easily separated using solid fluoride pellet absorption beds. No one has produced such a bomb, but Np-237's considerable fast fission cross section and low critical mass imply the possibility.^[85] When the Np-237 is kept in the reactor, it transmutes to short lived Pu-238. All reactors produce considerable neptunium, which is always present in high (mono)isotopic quality, and is easily extracted chemically.^[85]
• Neutron poisoning and tritium production from lithium-6 – Lithium-6 is a strong neutron poison; using LiF with natural lithium, with its 7.5% lithium-6 content, prevents reactors from starting. The high neutron density in the core rapidly transmutes lityum-6 ga tritiy, losing neutrons that are required to sustain break-even breeding. Tritium is a radioactive isotope of hydrogen, which is nearly identical, chemically, to ordinary hydrogen.^[86] In the MSR the tritium is quite mobile because, in its elemental form, it rapidly diffuses through metals at high temperature. If the lithium is isotopically enriched in lithium-7, and the isotopic separation level is high enough (99.995% lithium-7), the amount of tritium produced is only a few hundred grams per year for a 1 GWe reactor. This much smaller amount of tritium comes mostly from the lithium-7 – tritium reaction and from beryllium, which can produce tritium indirectly by first transmuting to tritium-producing lithium-6. LFTR designs that use a lithium salt, choose the lithium-7 izotop. In the MSRE, lithium-6 was successfully removed from the fuel salt via isotopic enrichment. Since lithium-7 is at least 16% heavier than lithium-6, and is the most common isotope, lithium-6 is comparatively easy and inexpensive to extract. Vacuum distillation of lithium achieves efficiencies of up to 8% per stage and requires only heating in a vacuum chamber.^[87] Ammo, about one fission in 90,000 produces geliy-6, which quickly decays to lithium-6 and one fission in 12,500 produces an atom of tritium directly (in all reactor types). Practical MSRs operate under a blanket of dry inert gas, usually helium. LFTRs offer a good chance to recover the tritium, since it is not highly diluted in water as in CANDU reactors. Various methods exist to trap tritium, such as hydriding it to titanium,^[88] oxidizing it to less mobile (but still volatile) forms such as sodium fluoroborate or molten nitrate salt, or trapping it in the turbine power cycle gas and offgasing it using copper oxide pellets.^[89](p41) ORNL developed a secondary loop coolant system that would chemically trap residual tritium so that it could be removed from the secondary coolant rather than diffusing into the turbine power cycle. ORNL calculated that this would reduce Tritium emissions to acceptable levels.^[86]
• Corrosion from tellurium – The reactor makes small amounts of tellur as a fission product. In the MSRE, this caused small amounts of corrosion at the grain boundaries of the special nikel qotishma, Xastelloy -N. Metallurgical studies showed that adding 1 to 2% niobiy uchun Xastelloy -N alloy improves resistance to corrosion by tellurium.^{[54](pp81–87)} Maintaining the ratio of UF
  ₄/UF
  ₃ to less than 60 reduced corrosion by keeping the fuel salt slightly reducing. The MSRE continually contacted the flowing fuel salt with a beryllium metal rod submerged in a cage inside the pump bowl. This caused a fluorine shortage in the salt, reducing tellurium to a less aggressive (elemental) form. This method is also effective in reducing corrosion in general, because the fission process produces more fluorine atoms that would otherwise attack the structural metals.^{[90](pp3–4)}
• Radiation damage to nickel alloys – The standard Hastelloy N alloy was found to be embrittled by neutron radiation. Neutrons reacted with nickel to form helium. This helium gas concentrated at specific points inside the alloy, where it increased stresses. ORNL addressed this problem by adding 1–2% titanium or niobium to the Hastelloy N. This changed the alloy's internal structure so that the helium would be finely distributed. This relieved the stress and allowed the alloy to withstand considerable neutron flux. However the maximum temperature is limited to about 650 °C.^[91] Development of other alloys may be required.^[92] The outer vessel wall that contains the salt can have neutronic shielding, such as boron carbide, to effectively protect it from neutron damage.^[93]
• Long term fuel salt storage – If the fluoride fuel salts are stored in solid form over many decades, radiation can cause the release of corrosive ftor gas and uranium hexafluoride.^[94] The salts must be defueled and wastes removed before extended shutdowns and stored above 100 degrees Celsius.^[77] Fluorides are less suitable for long term storage because some have high water solubility unless vitrified in insoluble borosilicate glass.^[95]
• Biznes modeli – Today's solid-fueled reactor vendors make long term revenues by fuel fabrication.^{[shubhali – muhokama qilish]} Without any fuel to fabricate and sell, an LFTR would adopt a different business model. There would be significant barrier to entry costs to make this a viable business. Existing infrastructure and parts suppliers are geared towards water-cooled reactors. There is little thorium market and thorium mining, so considerable infrastructure that would be required does not yet exist. Regulatory agencies have less experience regulating thorium reactors, creating potentials for extended delays.^{[iqtibos kerak ]}
• Development of the power cycle – Developing a large helium or supercritical carbon dioxide turbine is needed for highest efficiency. These gas cycles offer numerous potential advantages for use with molten salt-fueled or molten salt-cooled reactors.^[96] These closed gas cycles face design challenges and engineering upscaling work for a commercial turbine-generator set.^[97] A standard supercritical steam turbine could be used at a small penalty in efficiency (the net efficiency of the MSBR was designed to be approximately 44%, using an old 1970s steam turbine).^[98] A molten salt to steam generator would still have to be developed. Currently, molten nitrate salt steam generators are used in concentrated solar thermal power plants such as Andasol Ispaniyada. Such a generator could be used for an MSR as a third circulating loop, where it would also trap any tritium that diffuses through the primary and secondary heat exchanger^[99]

So'nggi o'zgarishlar

The Fuji MSR

The FUJI MSR was a design for a 100 to 200 MWe molten-salt-fueled thorium fuel cycle issiqlik selektsioner reaktor, using technology similar to the Oak Ridge National Laboratory Reactor Experiment. It was being developed by a consortium including members from Japan, the United States, and Russia. As a breeder reactor, it converts thorium into nuclear fuels.^[100] An industry group presented updated plans about FUJI MSR 2010 yil iyulda.^[101] They projected a cost of 2.85 cents per kilowatt hour.^[102]

The IThEMS consortium planned to first build a much smaller MiniFUJI 10 MWe reactor of the same design once it had secured an additional $300 million in funding, but IThEMS closed in 2011 after it was unable to secure adequate funding. A new company, Thorium Tech Solution (TTS), was founded in 2011 by Kazuo Furukawa, the chief scientist from IThEMS, and Masaaki Furukawa. TTS acquired the FUJI design and some related patents.

Chinese thorium MSR project

The People's Republic of China has initiated a research and development project in thorium molten-salt reactor technology.^[103] It was formally announced at the Xitoy Fanlar akademiyasi (CAS) annual conference in January 2011. Its ultimate target is to investigate and develop a thorium based molten salt nuclear system in about 20 years.^[104][105] An expected intermediate outcome of the TMSR research program is to build a 2 MW pebble bed fluoride salt cooled research reactor in 2015, and a 2 MW molten salt fueled research reactor in 2017. This would be followed by a 10 MW demonstrator reactor and a 100 MW pilot reactors.^[106][107] The project is spearheaded by Jiang Mianheng, with a start-up budget of $350 million, and has already recruited 140 PhD scientists, working full-time on thorium molten salt reactor research at the Shanghai Institute of Applied Physics. An expansion of staffing has increased to 700 as of 2015.^[108] As of 2016, their plan is for a 10MW pilot LFTR is expected to be made operational in 2025, with a 100MW version set to follow in 2035.^[109]

Flibe Energy

Kirk Sorensen, sobiq NASA scientist and Chief Nuclear Technologist at Teledyne Brown Engineering, has been a long-time promoter of thorium fuel cycle and particularly liquid fluoride thorium reactors. He first researched thorium reactors while working at NASA, while evaluating power plant designs suitable for lunar colonies. Material about this fuel cycle was surprisingly hard to find, so in 2006 Sorensen started "energyfromthorium.com", a document repository, forum, and blog to promote this technology. In 2006, Sorensen coined the suyuq ftorli torium reaktori va LFTR nomenclature to describe a subset of molten salt reactor designs based on liquid fluoride-salt fuels with breeding of thorium into uranium-233 in the thermal spectrum. In 2011, Sorensen founded Flibe Energy, a company that initially intends to develop 20–50 MW LFTR small modular reactor designs to power military bases. (It is easier to promote novel military designs than civilian power station designs in today's US nuclear regulatory environment).^[110][111] An independent technology assessment coordinated with EPRI va Janubiy kompaniya represents the most detailed information so far publicly available about Flibe Energy's proposed LFTR design.^[112]

Thorium Energy Generation Pty. Limited (TEG)

Thorium Energy Generation Pty. Limited (TEG) was an Australian research and development company dedicated to the worldwide commercial development of LFTR reactors, as well as thorium tezlashtiruvchi tizimlar. As of June 2015, TEG had ceased operations.

Alvin Vaynberg jamg'armasi

The Alvin Weinberg Foundation was a British charity founded in 2011, dedicated to raising awareness about the potential of thorium energy and LFTR. It was formally launched at the House of Lords on 8 September 2011.^{[113][114][115]} Unga amerikalik yadro fizikasi nomi berilgan Alvin M. Vaynberg, who pioneered the thorium eritilgan tuz reaktori tadqiqot.

Torkon

Thorcon is a proposed molten salt converter reactor by Martingale, Florida. It features a simplified design with no reprocessing and swappable cans for ease of equipment replacement, in lieu of higher nuclear breeding efficiency.

Nuclear Research and Consultancy Group

On 5 September 2017, The Golland Nuclear Research and Consultancy Group announced that research on the irradiation of molten thorium fluoride salts inside the Petten high-flux reactor amalga oshirilayotgan edi.^[116]

Shuningdek qarang

• IV avlod reaktori
• Thorium-based nuclear power
• Kichik yadro reaktori dizaynlari ro'yxati
• Passive nuclear safety
• Small modular reactor
• Torium energiya ittifoqi
• Tezlashtiruvchi boshqariladigan sub-kritik reaktor
• Energiya kuchaytirgichi

Adabiyotlar

Qo'shimcha o'qish

• Hargraves, Robert (2009). Maqsadimiz baland!: Torium energiyasi ko'mirdan arzonroq bo'lib, nafaqat global isishdan ko'proq narsani hal qiladi (PDF). BookSurge Publishing. ISBN  978-1-4392-2538-7. Arxivlandi asl nusxasi (PDF) 2011 yil 11 iyunda.
• Martin, Richard (2012). SuperFuel: Thorium, kelajak uchun yashil energiya manbai. Palgrave Makmillan. ISBN  978-0-230-11647-4.
• Kuper, N .; Minakata, D .; Begovich, M .; Crittenden, J. (2011). "Biz elektr energiyasini ishlab chiqarish uchun suyuq ftorli torium reaktorlaridan foydalanishni o'ylab ko'rishimiz kerakmi?". Atrof-muhit fanlari va texnologiyalari. 45 (15): 6237–8. Bibcode:2011 ENST ... 45.6237C. doi:10.1021 / es2021318. PMID  21732635.
• Yerning tiklanishi, Teodor B. Teylor va Charlz C. Xumpston, 166 bet, Harper & Row (1973) ISBN  978-0060142315
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• Torium yoqilg'isi tsikli - potentsial afzalliklari va muammolari, IAEA, 105 bet (2005) ISBN  978-9201034052
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• Leyn, Jeyms. A (1958). Suyuq yonilg'i reaktorlari. Addison-Uesli va AQSh AEC. p. 972.

Tashqi havolalar

• "Uran shunday o'tgan asr - Toriumga kiring, yangi yashil nuke" Simli jurnal maqolasi
• Torium olovdan keyingi eng katta energiya yutug'imi? Ehtimol. Forbes maqolasi
• Eritilgan tuz reaktorlari - Ralf Moir

Videolar

• TEDxYYC - Kirk Sorensen - Torium. TEDxYYC 2011 da LFTR haqida taqdimot
• Suyuq ftorli torium reaktori: qanday termoyadroviy bo'lishni xohlagan Doktor Djo Bonometti tomonidan Google TechTalk NASA / Naval aspiranturasi
• Torium eritilgan-tuzli reaktor: Nega bunday bo'lmadi? Google TechTalk Kirk Sorensen tomonidan Oak Ridge-da torium eritilgan tuz reaktorining rivojlanish tarixi, siyosiy iqlimi va dasturning bekor qilinishi uchun sabablar o'rganilmoqda.
• Kirk Sorensen - Global alternativ @ TEAC4 Kirk Sorensenning "Trium Energy Alliance" konferentsiyasida 4-chikagodagi taqdimoti.