CA1077680A - Fluidized reactor reduction of uf6 to uo2 - Google Patents
Fluidized reactor reduction of uf6 to uo2Info
- Publication number
- CA1077680A CA1077680A CA231,248A CA231248A CA1077680A CA 1077680 A CA1077680 A CA 1077680A CA 231248 A CA231248 A CA 231248A CA 1077680 A CA1077680 A CA 1077680A
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- Prior art keywords
- solids
- bed
- steam
- uranyl fluoride
- uranyl
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
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- Inorganic Compounds Of Heavy Metals (AREA)
Abstract
ABSTRACT OF THE DISCLOSURE
Producing sinterable uranium dioxide by establishing a fluidized bed of uranyl fluoride solids, maintaining the bed of uranyl fluoride solids at temperatures in excess of 730°C
while countercurrently contacting the solids with excess steam to convert the uranyl fluoride to triuranium octoxide; and thereafter fluidizing the triuranium octoxide at temperatures below about 500°C while countercurrently contacting the triuranium octoxide with excess hydrogen in the presence of steam whereby uranium dioxide is formed. The dioxide produced has a relatively low fluoride concentration.
Producing sinterable uranium dioxide by establishing a fluidized bed of uranyl fluoride solids, maintaining the bed of uranyl fluoride solids at temperatures in excess of 730°C
while countercurrently contacting the solids with excess steam to convert the uranyl fluoride to triuranium octoxide; and thereafter fluidizing the triuranium octoxide at temperatures below about 500°C while countercurrently contacting the triuranium octoxide with excess hydrogen in the presence of steam whereby uranium dioxide is formed. The dioxide produced has a relatively low fluoride concentration.
Description
1~77680 BACKGROUND OF l~lE INVENTION
2 This invention relates to a 2-stage fluid bed pro-
3 cess for the production of uranium diox~de from uranium hexa-
4 fluorideO In particular, th~s invention relates to new and i~proved techn~ques for converting uranium hexafluoride to a 6 sinterable uran~um dioxide of relatively low fluoride concen-7 tration. `
8 There are a number of fluid bed techniques-that 9 have been proposed for converting uranium hexafluoride to uranium dioxideO For example, UOS~ Patent 3,160,471 dis-11 closes a single stage fluidization process in which uranium 12 hexafluoride is contacted with sto~chfometrfc excess of steam 13 and hydrogen to convert the uranium hexafluoride to uranium 14 dioxide. In UOS. Patent 3,574,598 a 2-3tage flufd bed pro-cess is disclosed in which uranium hexafluoride, steam and 16 hydrogen are reacted in a first fluid bed react~r to form a 17 mixture of intermediate uranium oxide~O Theqe intermediate 18 urani~m oxide produc~s are then fluidized with team and hy-19 drogen in a second re~ctor where they are converted to uran-ium dioxide~ Although these processes offer the prom~se of 21 cost savings inherent in fluidfzation techntques, unfortunate-22 ly in order to reduce the fluoride content of the uranium 23 dioxide produced to acceptable level~, for example, betow 24 about 0.011 to 0.015 wt. % based on the weight of uran~um di-oxide produced, the solid uranium oxides must be maintained 26 within the bed for extensive periods of timeO Moreover, the 27 uranium dioxide i8 formed at relatively high temperatures 28 that adversely af~ect the sinterable quality of the d~oxideO
~ . .~ .
According to the present invention there is pro-31 vided an improved process for the conversion of uranium hex~-32 fluoride to ~interable uranium dioxide. The present proces~
~ 2 - ;~;
;, 1~77680 1 contemplates, as a first stage, establishing a fluidized bed 2 of uranyl fluoride (U02F2) solids, which is maintained at 3 temperatures above about 730C., and countercurrently con-4 tacting the uranyl fluoride solids with steam in excess of that required to convert the uranyl fluoride to trluranium 6 octoxide (U308). Thereafter, the triuranium octcxide is 7 fluidized in a second stage and reduced with hydrogen in the 8 presence of steam at temperatures below about 500C.
9 In the practice of the present invention, it is particularly pxeferred that the fluidized bed of uranyl 11 fluoride solids be established in a multiple bed reactor and l2 preferably a two-bed reactor. Uranium hexafluoride and ste~m 13 are introduced at temperatures ranging generally from about 14 658C. to about 780C. into a first fluid bed ~f seed particles of uranyl fluoride. The steam is used in amounts s~fficien.
16 to convert the uranium hexafluoridé to uranyl fluoride The 17 uranyl fluoride so produced is then introduced into the sèc-18 ond bed where it is flu~dized and contacted with steam in 19 excess of the stoichiometric amount required to convert the uranyl fluoride to triuranium octoxide. Temperatures in this 21 second bed are mainta~ned in the range of about 730C to 22 about 780C. and préferably above about 750C. Thus, the 23 fluoride concentration of the triuranium octoxide iæ below at 2~ least O.OlO wt. % and generally as low as abou~ 0.0025 to about 0.0005 wt. % thereby assuring that the U02 will be sub~
26 stant~ally free of fLuoride.
27 The triuranium octoxide so pxaduced is rapidly con-28 verted in a second stage reactor by fluidizing the triuranium 29 octoxide at temperatures below about 500C. and generally in the range of about 450 to 500C. while countercurrently con-31 tacting the uranium trioxide in the fluid bed with excess 32 hydrogen containing steam. Fo~ example~ ~he mols ra~io of .
~:` ' ' ' .
~, 1 hydrogen to ~eam ic generally in the range of 2 to 1 to 2 about 1.5 to 1. The ratio of hydrogen to triuranium octoxide 3 i~ generally in the range of 3 to 1 to about 2.5 to l. Thus, 4 the reduction is carried out at relatively low temperature~
with the concommitant result that the product is very easily 6 sintered. .
7 In another embodiment of the present invention a 8 bed of uranyl fluoride solids is established in a single bed 9 reactor and converted therein to triuranium octoxide by in-troducing uranium hexafluoride and ste~m into a bed-of seed 11 particles of uranyl fluoride and maintaining`the bed-tempera-12 ture in the range of about 730Co to about 780C. The amount 13 of ste~m used is in excess of that required to convert uran-14 ium hexafluoride to.triuranium octoxide. Thereafter-~he tri-uranium oxide is reduced in the second stage reactor with 16 hydrogen and s~eam at temperatures ranging from a~out 450C.
17 to about 500C.
18 These and other features of the present invention 19 will be better understood by reference to the detailed des-cription which follows, especially when ccnæider~d i~`connec-21 tion with the drawings hereinO
22 BRIEF DESCRIPTIO~ OF THE D~AWqNGS --.23 The single figure is a schematic diagram illustrat-2~ ing the use of two fluid bed reactors in the practice of the instant proce~s.
-27 Referring specifically to the drawing, two Beparate 28 fluidization reactors 10 and 20 are shown. Each of these 29 reactors i~ provided with a typical grid to support the flui-dized bed of solids. The design of the grid is not part of 31 the present invention and consequently the grid is merely 3~ indicated as lin2s 12 and 12a in reactor 10 and as line 22 .. 4 .
.
` 1077680 1 in reactor 20. Also, in reaetor 10 two flu~ ized beds of 2 solid~ are shown as 1 and la and in reactor 20 one fluidized 3 bed of solids ~ shown generally as 2.
In the practice of the present invention a fluid bed 1 of uranyl fluoride (U02~2) is established by seeding 6 the first reactor lQ with uranyl fluoride par~icles of flui-7 dizable particle size. F~r example, partiCle~ being an 8 average particle size of about 30~are sufficient. The 9 amount of seed material employed, of course, is not fixed but varies greatly depending upon the reactor size, desired 11 throughput and the like. Thereafter, uranium hexafluoride 12 and steam are introduced into fluid bed 1 of reactor 10. To 13 prevent channelling of the gases, the uranium he~afluoride 14 is preferably introduced via line 14 below grid pla~e~l2.
Steam i8 introduced via line 15 and passes upwardly through 16 the reactor into fluid bed 1. Optionally steam can be intro-7 duced into fluid bed 1 in substantially the samè manner as 18 the uranium hexafluoride by ano~her line ~not shown).
19 The temperature in bed 1 is malntained generally ~ in the range of from about 658C. to 780Co and preferably 21 658 C~ to 680C. The steam is used in amounts sufficfent to 22 convert the uranium hexa1uoride to uranyl fluoride.
23 ~ext, the uranyl fluoride is advanced to fluid bed 24 la by means of a downcomer 19 or other suitable means. The ~5 uranyl fluoride introduced into bed la is fluidized and 26 countercurrently contacted there with ste~m in excess of the 27 stoichiometric amount required to convert the uranyl-fluor-28 ~ lde to triuranium octoxideO The steam i5 introduced via 29 line 15. Gener~lly, the temperature ln bed la is maintained in the range of from about 730C. to about 780Co with about 31 750C. to about 760C. being preferred~
32 Optionally, a single bed of uranyl rluoride ~rti-~, .
.'. ' ' . ~
1 cles is established in a fluid bed reactor by introducing 2 uranium hexafluoride and steam ~nto a bed of seed particles 3 of uranyl fluoride. In this embodiment, however, the tem-4 perature of the bed is maintained in the range of about 730C.
to about 780C. and the excess steam is used to ultimately 6 convert the uranyl fluoride formed to triuranium oc~oxide.
7 In any event, generally the mole ratib of steam to 8 uranium hexafluoride introduced into reactor 10 will be in 9 the range of 10 to 1 and preferably in the range of~a~cut 5 to 1. Effluent gases are removed via line 8 and pass-through 11 a solid recovery system shown as vessel 16. Ihese solids can 12 be returned via-line 9 to fluid bed 1 or removed via line 17 for further processing- Gases leaving the solids recovery system 16 via line 18 may be recycled or recovered as so desired.
16 In view of the high temperatures preYailing in fluid bed la of reactor 10 and the large excess of steam, the uranyl 18 fluoride solids are rapidly oxidized to triuranium octoxide.
19 The trluranium octoxiae i8 removed, for example, via line 7 and introduced int o reactor 20. Line 7 is provided with 21 suitable means (not shown) to preven~ gases from reactor 20 22 entering reactor 10. - ~
23 In reactor 20, the uranyl triuranium octox~de is ~-24 ~luidized and reduced to uranium dioxide~ Generall~, the triuranium octoxide w~ll be maintained at temperatures below 26 about 500C., ~or example, in the range of ~bout-450~C. t~
27 a~out 500C., and preferably in the range of abou~ 470 to ` 28 475C. Hydrogen gas is introduced via line 23 to counter-29 currently contact the triuranium octoxide and reduce it to uranium dio~ide. The amount of hydrogen introduced into 31 reactor 20 is in excess of the stoichiometric amount of hy-. ~ c~fo~/~e 32 drogen required to convert the triuranium 4~kl~ to uranlum 10776~30 B 1 dioxide. For example, the mole ratio of hydrogen to iue~u~u~
- 2 triuranium octoxide is in the range of 3 to 1 to 205 to 1.
3 The mole ratio of hydrogen to steam is generally 4 2 to 1 and preferably 1.5 to 1. Apparently, the ~team en~
hances and/or catalyzes the reduction of triuranium octox~de 6 by hydrogen. Fines carried from reactor 20 are recovered for 7 example, by means of the separation vessel 24 which is con~
nected to reactor 20 via line 25. Such fines are removed via 9 line 26 or are transferred via line 28 to product removal line 27. The off gas which contains steam and hydrogen is 11 removed via line 29 and sent to a gas recovery facility where l2 the hydrogen can be separated and recycled ~~-13 By staging the conversion of uranium hexafluoride 14 to uranium dioxide in the manner described herein9 the fluor~ -ide content of the uranium dioxide is reduced to acceptable l6 levels below about 0.011 wt. X and the sinterabllity of the 17 uranium dioxide powder is enhanced.
24 .-~ 7 ~
.
- - , . .
~ .
. .
8 There are a number of fluid bed techniques-that 9 have been proposed for converting uranium hexafluoride to uranium dioxideO For example, UOS~ Patent 3,160,471 dis-11 closes a single stage fluidization process in which uranium 12 hexafluoride is contacted with sto~chfometrfc excess of steam 13 and hydrogen to convert the uranium hexafluoride to uranium 14 dioxide. In UOS. Patent 3,574,598 a 2-3tage flufd bed pro-cess is disclosed in which uranium hexafluoride, steam and 16 hydrogen are reacted in a first fluid bed react~r to form a 17 mixture of intermediate uranium oxide~O Theqe intermediate 18 urani~m oxide produc~s are then fluidized with team and hy-19 drogen in a second re~ctor where they are converted to uran-ium dioxide~ Although these processes offer the prom~se of 21 cost savings inherent in fluidfzation techntques, unfortunate-22 ly in order to reduce the fluoride content of the uranium 23 dioxide produced to acceptable level~, for example, betow 24 about 0.011 to 0.015 wt. % based on the weight of uran~um di-oxide produced, the solid uranium oxides must be maintained 26 within the bed for extensive periods of timeO Moreover, the 27 uranium dioxide i8 formed at relatively high temperatures 28 that adversely af~ect the sinterable quality of the d~oxideO
~ . .~ .
According to the present invention there is pro-31 vided an improved process for the conversion of uranium hex~-32 fluoride to ~interable uranium dioxide. The present proces~
~ 2 - ;~;
;, 1~77680 1 contemplates, as a first stage, establishing a fluidized bed 2 of uranyl fluoride (U02F2) solids, which is maintained at 3 temperatures above about 730C., and countercurrently con-4 tacting the uranyl fluoride solids with steam in excess of that required to convert the uranyl fluoride to trluranium 6 octoxide (U308). Thereafter, the triuranium octcxide is 7 fluidized in a second stage and reduced with hydrogen in the 8 presence of steam at temperatures below about 500C.
9 In the practice of the present invention, it is particularly pxeferred that the fluidized bed of uranyl 11 fluoride solids be established in a multiple bed reactor and l2 preferably a two-bed reactor. Uranium hexafluoride and ste~m 13 are introduced at temperatures ranging generally from about 14 658C. to about 780C. into a first fluid bed ~f seed particles of uranyl fluoride. The steam is used in amounts s~fficien.
16 to convert the uranium hexafluoridé to uranyl fluoride The 17 uranyl fluoride so produced is then introduced into the sèc-18 ond bed where it is flu~dized and contacted with steam in 19 excess of the stoichiometric amount required to convert the uranyl fluoride to triuranium octoxide. Temperatures in this 21 second bed are mainta~ned in the range of about 730C to 22 about 780C. and préferably above about 750C. Thus, the 23 fluoride concentration of the triuranium octoxide iæ below at 2~ least O.OlO wt. % and generally as low as abou~ 0.0025 to about 0.0005 wt. % thereby assuring that the U02 will be sub~
26 stant~ally free of fLuoride.
27 The triuranium octoxide so pxaduced is rapidly con-28 verted in a second stage reactor by fluidizing the triuranium 29 octoxide at temperatures below about 500C. and generally in the range of about 450 to 500C. while countercurrently con-31 tacting the uranium trioxide in the fluid bed with excess 32 hydrogen containing steam. Fo~ example~ ~he mols ra~io of .
~:` ' ' ' .
~, 1 hydrogen to ~eam ic generally in the range of 2 to 1 to 2 about 1.5 to 1. The ratio of hydrogen to triuranium octoxide 3 i~ generally in the range of 3 to 1 to about 2.5 to l. Thus, 4 the reduction is carried out at relatively low temperature~
with the concommitant result that the product is very easily 6 sintered. .
7 In another embodiment of the present invention a 8 bed of uranyl fluoride solids is established in a single bed 9 reactor and converted therein to triuranium octoxide by in-troducing uranium hexafluoride and ste~m into a bed-of seed 11 particles of uranyl fluoride and maintaining`the bed-tempera-12 ture in the range of about 730Co to about 780C. The amount 13 of ste~m used is in excess of that required to convert uran-14 ium hexafluoride to.triuranium octoxide. Thereafter-~he tri-uranium oxide is reduced in the second stage reactor with 16 hydrogen and s~eam at temperatures ranging from a~out 450C.
17 to about 500C.
18 These and other features of the present invention 19 will be better understood by reference to the detailed des-cription which follows, especially when ccnæider~d i~`connec-21 tion with the drawings hereinO
22 BRIEF DESCRIPTIO~ OF THE D~AWqNGS --.23 The single figure is a schematic diagram illustrat-2~ ing the use of two fluid bed reactors in the practice of the instant proce~s.
-27 Referring specifically to the drawing, two Beparate 28 fluidization reactors 10 and 20 are shown. Each of these 29 reactors i~ provided with a typical grid to support the flui-dized bed of solids. The design of the grid is not part of 31 the present invention and consequently the grid is merely 3~ indicated as lin2s 12 and 12a in reactor 10 and as line 22 .. 4 .
.
` 1077680 1 in reactor 20. Also, in reaetor 10 two flu~ ized beds of 2 solid~ are shown as 1 and la and in reactor 20 one fluidized 3 bed of solids ~ shown generally as 2.
In the practice of the present invention a fluid bed 1 of uranyl fluoride (U02~2) is established by seeding 6 the first reactor lQ with uranyl fluoride par~icles of flui-7 dizable particle size. F~r example, partiCle~ being an 8 average particle size of about 30~are sufficient. The 9 amount of seed material employed, of course, is not fixed but varies greatly depending upon the reactor size, desired 11 throughput and the like. Thereafter, uranium hexafluoride 12 and steam are introduced into fluid bed 1 of reactor 10. To 13 prevent channelling of the gases, the uranium he~afluoride 14 is preferably introduced via line 14 below grid pla~e~l2.
Steam i8 introduced via line 15 and passes upwardly through 16 the reactor into fluid bed 1. Optionally steam can be intro-7 duced into fluid bed 1 in substantially the samè manner as 18 the uranium hexafluoride by ano~her line ~not shown).
19 The temperature in bed 1 is malntained generally ~ in the range of from about 658C. to 780Co and preferably 21 658 C~ to 680C. The steam is used in amounts sufficfent to 22 convert the uranium hexa1uoride to uranyl fluoride.
23 ~ext, the uranyl fluoride is advanced to fluid bed 24 la by means of a downcomer 19 or other suitable means. The ~5 uranyl fluoride introduced into bed la is fluidized and 26 countercurrently contacted there with ste~m in excess of the 27 stoichiometric amount required to convert the uranyl-fluor-28 ~ lde to triuranium octoxideO The steam i5 introduced via 29 line 15. Gener~lly, the temperature ln bed la is maintained in the range of from about 730C. to about 780Co with about 31 750C. to about 760C. being preferred~
32 Optionally, a single bed of uranyl rluoride ~rti-~, .
.'. ' ' . ~
1 cles is established in a fluid bed reactor by introducing 2 uranium hexafluoride and steam ~nto a bed of seed particles 3 of uranyl fluoride. In this embodiment, however, the tem-4 perature of the bed is maintained in the range of about 730C.
to about 780C. and the excess steam is used to ultimately 6 convert the uranyl fluoride formed to triuranium oc~oxide.
7 In any event, generally the mole ratib of steam to 8 uranium hexafluoride introduced into reactor 10 will be in 9 the range of 10 to 1 and preferably in the range of~a~cut 5 to 1. Effluent gases are removed via line 8 and pass-through 11 a solid recovery system shown as vessel 16. Ihese solids can 12 be returned via-line 9 to fluid bed 1 or removed via line 17 for further processing- Gases leaving the solids recovery system 16 via line 18 may be recycled or recovered as so desired.
16 In view of the high temperatures preYailing in fluid bed la of reactor 10 and the large excess of steam, the uranyl 18 fluoride solids are rapidly oxidized to triuranium octoxide.
19 The trluranium octoxiae i8 removed, for example, via line 7 and introduced int o reactor 20. Line 7 is provided with 21 suitable means (not shown) to preven~ gases from reactor 20 22 entering reactor 10. - ~
23 In reactor 20, the uranyl triuranium octox~de is ~-24 ~luidized and reduced to uranium dioxide~ Generall~, the triuranium octoxide w~ll be maintained at temperatures below 26 about 500C., ~or example, in the range of ~bout-450~C. t~
27 a~out 500C., and preferably in the range of abou~ 470 to ` 28 475C. Hydrogen gas is introduced via line 23 to counter-29 currently contact the triuranium octoxide and reduce it to uranium dio~ide. The amount of hydrogen introduced into 31 reactor 20 is in excess of the stoichiometric amount of hy-. ~ c~fo~/~e 32 drogen required to convert the triuranium 4~kl~ to uranlum 10776~30 B 1 dioxide. For example, the mole ratio of hydrogen to iue~u~u~
- 2 triuranium octoxide is in the range of 3 to 1 to 205 to 1.
3 The mole ratio of hydrogen to steam is generally 4 2 to 1 and preferably 1.5 to 1. Apparently, the ~team en~
hances and/or catalyzes the reduction of triuranium octox~de 6 by hydrogen. Fines carried from reactor 20 are recovered for 7 example, by means of the separation vessel 24 which is con~
nected to reactor 20 via line 25. Such fines are removed via 9 line 26 or are transferred via line 28 to product removal line 27. The off gas which contains steam and hydrogen is 11 removed via line 29 and sent to a gas recovery facility where l2 the hydrogen can be separated and recycled ~~-13 By staging the conversion of uranium hexafluoride 14 to uranium dioxide in the manner described herein9 the fluor~ -ide content of the uranium dioxide is reduced to acceptable l6 levels below about 0.011 wt. X and the sinterabllity of the 17 uranium dioxide powder is enhanced.
24 .-~ 7 ~
.
- - , . .
~ .
. .
Claims (7)
1. A method of producing sinterable uranium dioxide com-prising:
(a) establishing a fluidized bed of uranyl fluoride solids;
(b) maintaining the bed of uranyl fluoride solids at temperatures in excess of 730°C. while countercurrently contac-ting said solids with excess steam to convert the uranyl fluoride to triuranium octoxide; and (c) thereafter fluidizing the triuranium octoxide at temperatures below about 500°C. while countercurrently contacting the triuranium octoxide with excess hydrogen in the presence of steam whereby uranium dioxide is formed.
(a) establishing a fluidized bed of uranyl fluoride solids;
(b) maintaining the bed of uranyl fluoride solids at temperatures in excess of 730°C. while countercurrently contac-ting said solids with excess steam to convert the uranyl fluoride to triuranium octoxide; and (c) thereafter fluidizing the triuranium octoxide at temperatures below about 500°C. while countercurrently contacting the triuranium octoxide with excess hydrogen in the presence of steam whereby uranium dioxide is formed.
2. The method of claim 1 wherein said bed of uranyl fluo-ride solids of step (a) is established by introducing uranium hexafluoride and steam countercurrently into a first fluid bed of seed particles of uranyl fluoride solids and maintaining the temperatures of said first bed in the range of from about 658°C
to about 780°C whereby uranyl fluoride solids are obtained and thereafter introducing said uranyl fluoride solids into a second bed for fluidization therein, thereby establishing a fluid bed of uranyl fluoride solids.
to about 780°C whereby uranyl fluoride solids are obtained and thereafter introducing said uranyl fluoride solids into a second bed for fluidization therein, thereby establishing a fluid bed of uranyl fluoride solids.
3. The method of claim 2 wherein the temperature of the bed is maintained in the range of about 658°C. to about 680°C
and the uranyl fluoride solids are then transferred to a second fluid bed and further treated as in steps (b) and (c).
and the uranyl fluoride solids are then transferred to a second fluid bed and further treated as in steps (b) and (c).
4. The method of claim 3 wherein triuranium octoxide is fluidized and reduced in a separate reactor at a temperature in the range of from about 450°C. to about 500°C. with excess hydrogen and steam, the ratio of hydrogen to triuranium octoxide being in the range of from about 3 to 1 to about 2.5 to 1 and the ratio of hydrogen to steam being in the range of about 2 to 1 to about 1.5 to 1.
5. The process of claim 1 wherein the temperature of the fluidized bed of uranyl fluoride solids is maintained at a tem-perature in the range of about 730°C to 780°C.
6. me process of claim 1 wherein the ratio of steam to uranium hexafluoride introduced into the bed of uranyl fluoride solids ranges from about 10 to 1 to about 5 to 1.
7. A staged fluidized process of converting uranium hexa-fluoride to uranium dioxide comprising countercurrently intro-ducing uranium hexafluoride and steam into contact with a first fluid bed of seed particles of uranyl fluoride solids; maintain-ing the first bed of uranyl fluoride solids at temperatures in the range of about 658°C. to 680°C whereby uranium hexafluoride is converted to uranyl fluoride; transferring said uranyl fluoride solids to a second fluid bed; maintaining said second fluid bed at temperatures in the range of about 730°C to about 780°C; while countercurrently contacting said second fluidized bed of uranyl solids with excess steam for a time sufficient to convert uranyl fluoride solids to triuranium octoxide;
transferring said triuranium octoxide solids into a second reactor; fluidizing and countercurrently contacting said tri-uranium octoxide solid with excess hydrogen in the presence of steam at temperatures in the range of about 450°C to 500°C
whereby said triuranium octoxide solids are converted to uranium dioxide.
transferring said triuranium octoxide solids into a second reactor; fluidizing and countercurrently contacting said tri-uranium octoxide solid with excess hydrogen in the presence of steam at temperatures in the range of about 450°C to 500°C
whereby said triuranium octoxide solids are converted to uranium dioxide.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA231,248A CA1077680A (en) | 1975-07-10 | 1975-07-10 | Fluidized reactor reduction of uf6 to uo2 |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA231,248A CA1077680A (en) | 1975-07-10 | 1975-07-10 | Fluidized reactor reduction of uf6 to uo2 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1077680A true CA1077680A (en) | 1980-05-20 |
Family
ID=4103578
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA231,248A Expired CA1077680A (en) | 1975-07-10 | 1975-07-10 | Fluidized reactor reduction of uf6 to uo2 |
Country Status (1)
| Country | Link |
|---|---|
| CA (1) | CA1077680A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0322481A1 (en) * | 1986-05-27 | 1989-07-05 | Mitsubishi Materials Corporation | Method of preparing uranium dioxide powder from uranium hexafluoride |
-
1975
- 1975-07-10 CA CA231,248A patent/CA1077680A/en not_active Expired
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0322481A1 (en) * | 1986-05-27 | 1989-07-05 | Mitsubishi Materials Corporation | Method of preparing uranium dioxide powder from uranium hexafluoride |
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