ML20151B650
| ML20151B650 | |
| Person / Time | |
|---|---|
| Site: | 07000036 |
| Issue date: | 12/28/1988 |
| From: | ABB COMBUSTION ENGINEERING NUCLEAR FUEL (FORMERLY |
| To: | |
| Shared Package | |
| ML20151B640 | List: |
| References | |
| NUDOCS 8804110095 | |
| Download: ML20151B650 (30) | |
Text
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_y CCMBUSTION A ENGINEERING SN!1-33 AllEllDfiEflT APPLICATI0ft LIST OF PAGES REVISED 12-28-87 Page #
Revision #
I.1-2 2
I.1-3 2
1.4-5 2
1.4-6 1
II.8-7 2
11.8-8 1
11.8-9 1
II.8-15 1
11.8-17 1
II.8-19 1
11.8-20 2
11.8-21 1
11.8-22 1
11.8-23 1
11.8-24 1
11.8-29 1
11.8-31 1
11.9-1 1
11.9-2 1
11.9-4 1
11.9-5 1
II.9-Sa 1
11.9-10 1
11.9-17 1
11.9-26 1
11.9-29 1
11.9-31 1
II.9-33 0
8804110095 071228 ADOCK 070 g 6 PDR C
Power Systems Post Off co Bos 107 (314) 937-4691 Combu: tion Eng neenng. Inc Highw af P (314) 296 E610 Hematit(. M ssoun 6304 7 j
e 1.4 Possession Limits Combustion Enginearing, Inc., requests authorization to receive, use, possess, store and transfer at its Hematite site, the following quantities of SNM and source materials:
i Material Form Quantity Uranium enriched to Any*
8,000 kilograms maximum of 5.~0 weight contained U-235 percent in the U-235 isotope Uranium to any enrichment Any*
350 grams l
in the U-235 isotope Source material Uranium and/or 50,000 kilograms Thorium, Any*
Cobalt-60 Sealed Sources 40 millicuries total 1.5 Location Where Material Will Be Used All manufacturing activities are carried out within the security fenced area located on the central site tract. Manufacturing activities utilizing radioactive materials are housed in several buildings containing equipment for conversion of.UF6 to U02 fabrication of UO2 nuclear fuel pellets and related processes.
Section 1.7 contains a list of the buildings, identified by number and name, showing their present utilization.
1.6 Definitions s
Terminology is as defined.in standard references (e.g.', Title 10 of the Code of Federal Regulations) or is explained in the section whert it appears if unique to this application.
- Excluding metal powders License No. SNM-33, Docket 70-36 Revision:
2 Date: 12/28/87 Page:
1.1-2 i
t a-
to 1.7 Authorized Activities Receive, possess, use and transfer Special Nuclear liaterial under Part 70 of the Regulations of the Nuclear Regulatory Coninission in order to manufacture nuclear reactor fuel utilizing low-enriched uranium (up to 5.0 weight percent in the isotope U-235).
Receive, possess, use and transfer Source Material under Part 40 of the Regulations of the Nuclear Regulatory Commission.
Source materials are used for the same purposes as SNii, and are generally used for start-up testing of a new process.
Sealed cobalt-60 sources are used for instrument calibration and testing.
Authorized activities are conducted in the following
]
buildings and facilities on the Hematite site:
Number Name Present Utilization 101 Tile Barn Emergency Center and equipment storage 110 New Office Building Guard Station and offices 120 Wood Barn Equipment storage 0xide Building UF6 to U02 Conversion, and Dock UF6 receiving 235 West Vault Source material storage 240 240-1 Offices and Cafeteria 240-2 Recycle and Recovery area 240-3 Incinerator and storage 240-4 Laboratory and Maintenance Shop 250 Boiler Room Steam supply, and Warehouse Storage 251 Warehouse Shipping and Receiving, storage 252 South Vault Radioactive waste storage 255 Pellet Plant Pellet Fabrication, storage and packaging.
License No. SNM-33, Docket 70-36 Revision:
2 Date: 12/28/07 Page: I.1-3
1 r-4.2.3 Safety Margins for Individual Units (continued) c.
lluclear safety shall be independent of the degree of moderation between units up to the maximum credible mist density. The maximum mist density will be deter-mined by studying all the sources of water in the vicinity of the single units or arrays.
The maximum mist i
density may be limited by design and/or by administrative controls.
d.
Criteria used in the choice of fire protection in areas
' potential criticality accidents (when moderators are present) shall be justified, e.
Nuclear safety shall be independent of neutron reflector thickness for the reflector of interest.
f.
Optimum conditions (limiting case) of water moderation and heterogeneity credible for the system shall be determined in all calculations.
g.
The analytical method (s) used for criticality safety f
analysis and the source of validation of the method (s) shall be specified.
h.
Safety margins for ino;vidual units and arrays shall be l
based on accident conditions such as flooding, multiple batching, and fire.
j
- i. The method of deriving applicable multiplication factors shall be specified.
4.2.4 Limits for Safe Individual Units (SIUs)
Table 4.2.4 Safe Individual Unit Limits for 5 5.0% enriched U02 at optimum moderation. All Mass and Volume limits have been adjusted to provide constant spacing areas for the enrichment shown. Hetero-geneous limits have been developed with optimum rod sizes (up to 0.4" diameter) taken to allow for pellet chips, etc.
License No. SNM-33, Docket 70-36 Revision:
2 Date:
12/28/87 Page: 1.4-5
i..
r-4,.2.4 Limits for Safe Individual Units (SIUs) (continued)
HOMOGENE0US HETEROGENE0US j
- Limit, f*
Limit f*
Hass (Kg U0 )
2
- 2.5% V
54
.19 50
.26
>2.5 - 3.0% "
41
.23 38
.29
>3.0 - 3.2% "
36
.23 36
.29
>3.2 - 3.4% "
35
.25 33
.29
>3.4 - 3.6% "
32
.26 30
.30
>3.6 - 3.8% "
28
.26 27
.29
>3.8 - 4.1% "
24
.25 24
.27
>4.1 - 4.3% "
22
.26 22
.27
>4.3 - 4.5% "
20
.27 20
.27
>4.5 - 4.7% "
18
.26 18
.27
>4.7 - 5.0% "
16
.27 16
.27 HOMOGENEOUS HETEROGENE0US Limit f*
Limit f*
Volume (liters)
<3.5%
31
.39 22
.40 3.5 - 4.1 25
.38 18
.38
>4.1 - 5.0 22
.22 9
.38 Cylinder Diameter (inc.hes)
<3.5 10.7
.34 9.5
.36 3.5 - 4.1 9.8
.33 8.9
.34
>4.1 - 5.0 9.2
.34 8.4
.35 Slab Thickness (inches)
<3.5 5.1
.36 4.1
.22 3.5 - 4.1 4.6
.32 4.0
.28
- Fraction of the equivalent unreflected critical spherical volume or mass 4.2.5 Surface Density Method The surface density method may be used to evaluate arrays of SIUs where each mass limit has a fraction critical of 50.3, and volume and cylinder limits have a fraction critical of 50.4.
Spacing for mass limited SIVs is such that the contained UO2 J
and l
License No. SN!1-33, Docket 70-36 Revision:
1 Date:
12/28/87 Page:
1.4-6 i
e 8.1.5 Blending (continued)
Blenders are arranged on six foot centers forming an inline array and are located at least four feet from other SNM-bearing equipment.
8.1.6 Packaging and Storage Dry UO2 product is transferred into stainless steel cans (9.75" d X 11" long) in the ventilated powder packaging hoods. A 4 mil poly bag may be used as an inner liner.
If used, it is sealed at the top with tape.
The can lid is a friction-fit type which is sealed on the outside with tape.
This precludes any in-leakage of moisture from atmospheric humidity (the powder is not hygroscopic) or flooding. Thus, the UO2 product is kept dry (typically
<.05% moisture) and moderation control is assured under all conditions.
Section 11.9.7 describes all moderation controls in detail.
The sealed cans of dry U02 product are then transferred to one of 5 roller conveyors on the north side of i
Building #255 as shown in Drawing 0-5007-2001, 1
Sheet 9 of 9.
The entire building is above the 100 year flood level as determined by the U.S. Army Corps of Engineers in their Special Study for Joachim Creek, dated March 1980.
Even if flooding were possible, the 30 Kg weight of the cans containing high density 002 would prevent them from floating and being moved.
Building #255 is not sprinklered and firefighting would be by dry chemical means. Thus, j
criticality safety is assured through moderation control (<
5.0% enriched UO2 cannot be made critical without moderaticn).
i License No. SNM-33, Docket 70-36 Revision:
2 Date: 12/28/87 Page: 11.8-7
i I
8.2 Pellet Fabrication U0 from the conversion process may also be withdrawn in 2
5 gallon pails to be agglomerated and granulated to provide feed for pellet pressing.
1 Af ter pressing, pellets are dewaxed, sintered, ground and inspected.
They are then packaged for shipment.
Process flow is shown in Figure 11.8.1.
8.2.1 Agglomeration and Granulation U02 powder from the blenders is transferred to a V-blender having a total volume of 25.7 liters.
The blender is mounted on a scale and binders and other materials are added in pre-determined quantities. The agglomerated material is discharged through a hopper to a drying belt which can contain up to a 1 inch thickness of material.
The dry material is then dropped to a 15 liter granulator.
This agglomerated press feed is then transferred to a press feed blender or into metal buckets (11" 6 x 13" long) equipped with metal lids (which are tightly sealed with a locking clamp-ring) for storage on a 1 inch thick steel mezzanine located above the product storage conveyors.
This mezzanine is 81 feet above the concrete floor and the buckets are stored in a 13 x 13 array on 24-inch centers.
Metal rings are used to maintain this spacing.
The following conservative assumptions were incorporated in the calculational model of the powder storage and the mezzanine press feed storage areas:
- 1. The containers on the lower level were modelled as 9.75 inch diameter by 11 inch high cylindrical containers containing 35 kg of UO2 with.05 w/o water.
The steel structure of the cans were not modelled.
1 License fio. SNil-33, Docket 70-36 Revision:
1 Date:
12/28/87 Page:
11.8-8
l" 8.2.1
- Agglomeration and Granulation (continued)
- 2. The lower level contained no external mist.
- 3. The containers on the upper level were modelled as 11 inch diameter by 13 inch high cylindrical containers con-taining 41.0 kg of UO with 2.0 w/o water.
The steel 2
structure of the cans were not modelled.
- 4. The upper level assumed a.05 g/cc external mist.
- 5. The lower level assumed the cans were stacked as shown in drawing 05007-2001 in the +/- x direction (horizontally) and that the cans were touching in the +/- z direction (depth) and infinite in length.
- 6. The upper level assumed a seperation distance of 2 feet between centers in the x direction and 1.7 feet (2.0 feet actual) between centers in the z direction and infinite in length.
- 7. The systen was reflected in the +/- x and z directions.
The K-eff obtained for the system is 0.65867 0.00862.
Each agglomeration blender and associated hopper is assigned seven square feet of floor area, thereby permitting one mass in the blender and one in the hopper.
This multiple unit approach is discussed in Appendix A.
This equipment has also been shown to be nuclearly safe by solid angle calculations. (Section II.9.6)
The V-blenders are enclosed in a ventilated hood having sufficient air flow to assure a minimum face velocity of 100 ft/ min.
8.2.2 Pressing Granulated material, contained in 5-gallon pails, is considered to be homogeneous for criticality safety evaluations. The 5-gallon pails of blended material are attached to the press-feed hopper mounted above each press.
From this hopper the Date: 12/28/87 License No. SNM-33, Docket 70-36 Revision:
1 Page: 11.8-9
^
4
- 8. 5.1 UFg Cylinder Washing (continued).
d) The uranium in the wash solution will be precipitated by the addition of Anhydrous Anmonia.
The precipitate will be filtered on a 12" X 12" filter press.
e) Filtrate will be concentrated by evaporation, sampled and alpha and beta counted.
It will then be solidified by adding cement and packaged' for shipment to licensed burial.
8.6.
Analytical Services Analytical services are provided in several laboratory areas.
Stim of any enrichment may be handled in these areas.
The laboratories are divided into sections consistent with the testing techniques employed.
There are a general lab area, physical testing areas, office areas and storage.
The material handled includes feed material samples, process i
control samples, final product samples, and residue' samples;.
Such samples may be liquid or solid.
Analyses are performed using destructive and non-destructive techniques.
Unused sample portions are returned to the process streams. Analytical residues are collected, analyzed, and removed from the area for solidification for shipment to a licensed burial site or stored for recovery.
1 a.
General Laboratory Wet and dry analytical methods are used. The quantity of Stim in this area will be limited to 740 grams of U-235.
However, for enrichments in excess of 5.0%, a limit of 350 gm U-235 applies.
License fio. St4M-33, Docket 70-36 Revision:
1 Date: 12/28/87 Page: 11.8-15 i
8.7 Scrap Recovery 8.7.1
System Description
The Scrap Recovery Process is designed for wet recovery and blending.of scrap materials containing uranium having a maximum enrichment of 5.0%.
Clean dry scrap recycle (Section 11.8.4) and UF6 cylinder wash precipitation (Section II.8.5.ld) operations are also conducted in the Recycle / Recovery Area (240-2).
Except as specified, all units of equipment conform to the limits specified for safe mass, volume or cylinder diameter, and are spaced to conform with spacing requirements for SIUs.
The uranium bearing units and their associated spacings are shown on Dwg. D-5009-2012, Rev. 5, and the equipment layout is shown on Dwg. D-5009-2010, Rev. 4.
fiaterial flow diagrams are shown on the following drawings:
0-5009-1011 Rev. 2 240-2 R/R Equipment Flow Diagram B-5009-1007 Rev.1 240-2 R/R Process Flow B-5009-1008 Rev. 2 240-2 R/R Wet Recovery System B-5009-1009 Rev. 1 240-2 R/R UF6 Cylinder Wash 8.7.2 0xidation and Reduction Wet recovery operations will be performed on all types of scrap materials such as contaminated uranium compounds, clean-up residues and combustible materials with recoverable uranium content. Most of these materials require oxidation and reduction prior to introduction into the Wet Recovery System, and are loaded into furnace trays in the muffle box hood. This hcod is operated on a mass limit.
License tio. Stim-33, Docket 70-36 Revision:
1 Date: 12/28/87 page: 11.8-17
8.7.2 0xidation and Reduction (continued)
Cooled boxes are unloaded in the muffle box hood, and the material processed through such steps as granulation, magnetic separation, sampling, weighing, and blending, as appropriate.
Each of these operations is performed under a safe mass limit.
Material thus prepared is now ready for introduction into the first step of the Wet Recovery System.
8.7.3 Dissolution A preweighed charge of homogeneous material is introduced into a 9-3/4" diameter X 16" long vessel which is located in the slurry feed hood. This hood is limited to one safe mass. The material is slurried with water and transferred to a dissolver.
The dissolver is 9-3/4" diameter x 51" long. With the addition of nitric acid, the uranium is dissolved into a solution having a concentration of 50 to 250 grams per liter. Concentrations of uranium in the 300 gram / liter range and higher form slurries which cannot be pumped by the centrifugal transfer pump.
The critical diameter for a fully reflecr.ed infinitely long cylinder containing 5.0 wt % U at optium internal moderation 235 is 10.4 inches. The critical diameter for a unreflected infinite I
cylinder is 13.7 inches.
Therefore, a 9.75 inch diameter cylinder even at optimum internal moderation is a safe cylinder.
Non-homogeneous materiai (e.g., pellets) will not be introduced into the dissolution step.
License No. SNM-33, Docket 70-36 Revision:
1 Date: 12/28/87 Page: 11.8-19
l c.
l s
1 l
l 8.7.3 Dissolution (continued)
Both the slurry and dissolver vessels have assigned spacing areas greater than 5 ft* per ft. of length.
8.7.4 Filtration, Storage, and Dilution Af ter allowing digestion time to insure complete uranium dissolution, the U0 (NO3)2 solution may still contain acid 2
insolubles and is pumped through a filter press to remove these solids.
The filter press is 8" x 8" x 8-1/2" and has an active volume of less than the allowable safe volume for non-homogeneous material.
Af ter filtration, the solution is pumped into two safe diameter (6" diameter by 5' long) Pyrex clarity check vessels.
If any evidence of suspended solids remaining in the solution is observed, it will be recirculated through the filter until a clear solution'is obtained prior to release to the holding tank.
The holding tank has a maximum capacity of 1285 gallons, and is also used for dilution and blending.
The holding tank is poisoned with Raschig rings in accordance with ANSI Standard N16.4-1979.
Two Raschig ring sample tubes are provided to enable inspection for accumulation of solids and to provide samples for testing the physical and chemical properties of the rings.
These inspections and tests will be conducted in accordance with the ANSI Standard.
License No. SNS 33, Docket 70-36 Revision:
2 Date: 12/28/87 Page: 11.8-20
l a
l 8.7.4 Filtrution, Storage, and Dilution (continued)
The acid insoluble filter and the clarity check vessels are assigned exclusion areas conforming with surface density spacing requirements.
These exclusion areas are shown on Dwg. D-5009-2012, Rev. 5.
There are no sumps nor floor drains in the 240-2 area to which process material could flow from leaks or rupture of the equipment.
8.7.5
![04 Precipi ta tion Diluted UO (NO )2 solution is transferred to a horizonal 2
3 trough precipitator (8-3/8" x 12-5/3" x 10' long). An overflow is located at a height of 9 inches to assure an active cross sectional area equivalent to a 9.8" diameter cylinder. Any overflow from this trough is collected in a (9 3/4" diameter x 39" long) overflow vessel.
The critical diameter for a fully reflected cylinder containing 5.0 wt % V' " at optimum moderation is 10.4 inches.
The critical diameter for an unreflected cylinder is 13.7 inches. The trough precipitator is essentially unreflected.
Further, the leakage for a rectangular tank is greater than for an equivalent cross section area cylinder. Therefore, the 9.8 inch precipitator and overflow vessel are safe units.
The pH of the solution is adjusted with amonium hydroxide from the amonium hydroxide makeup system.
This systen consists of a sealed tank with a vent to the atnosphere, j
Additional makeup solutions are introduced from tank 4-2 to precipitate the uranium as 00. After aging and the 4
final pH adjustnent is completed, the UO slurry is 4
discharged to a 9 3/4" diameter x 33" long centrifuge feed vessel.
License No. SNM-33, Docket 70-36 Revision:
1 Date: 12/28/87 Page: 11.8-21
e 8.7.6 U.[04 Separation The precipitated slurry is transferred from the centrifuge feed vessel into a centrifuge which has a maximum volume of 7.63 liters. The cake is discharged, by gravity, from the centrifuge into a steam heated screw conveyor dryer.
z The dryer has a total cross sectional area of 75.17 in (this includes the internal screw conveyor) The actual net internal volume available for uranium is 107.62 liters, based on the manufacturer's design data, and allowing for the volume displaced by the internal screw mechanism.
The centrifuge is located in line with the dryer, and has an internal volume of 7.63 liters.
i The UO4 centrifuge-dryer-pail complex, as sketched below, has been evaluated in a 1000 x 1000 array to establish safe spacing requirements. The evaluation was made using i
I KENO with Hansen-Roach cross sections. The geometrical j
model used in the KEN 0 calculations is shown in Figure 11.8-2.
I l
U(5.0) 02 + H2O f
. _p._ -
l 2 gm U/cc U
x= 2' I I
l_
J Z = 59" x=2' e
+
x=2' 4-Reflector assumptions used were a 16" thick concrete slab below and a 4: thick concrete slab above the complex.
License No. SNM-33, Docket 70-36 Revision:
1 Date: 12/28/87 Page: 11.8-22
.. _ _. _.. _ _. _ -.. - - _ - - - -. _ _,, _ - - -. _ _ _ _ - _. ~ _ _. _ _. _ -,..
't C.
a 4* Thick Concrete Sla./
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3::
Centrifuge) 8.41" d o
Cylinder 7
8.41" high "w
10" high 11.5* wide Slab.
3.75" deep m
y 1
Cylinder 14' long i
i w
9.8" 6 m
Z = 59"
\\
i
/18" top width
~-
71-
$1ab 9
/ 8.375" deep 8
(Dryer) 12" t.cttern width c
13.5" height 2
(centerline) 6.91" d 9.77" height
- N C
(centerline) e--Cylinder l
co B
N 4" d
.N 9.5" high rylinder 1
/
e j
g 11.25" (
U (5.Q 02 + H2O 13* high.
(Pail)
% Cylinder
'2 gm U/cc
,(All units full)
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/ / / / / / / / / / / ! dc[Cder[6dla[ ! ! ! ! !
16 T WMir u. /9$7 7c USA 7EtrfM/
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SKETCH 4 - KENO MODEL - CENTRIFUGE / DRYER / PAIL C(,HBtNATION y a E%
C-
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N C3 RS
8.7.6 g4 Separation (continued)
The KEtt0 calculation gave keff=0.8966
.0099 at an optimum U0 2 density of 2.0 gm/cc.
The following conservative assumptions were incorporated in the calculation:
t 5.0 wt % U* " instead of the
- 1. The powder was assumed to be UO2 actual UO. The powder density was assumed to be 2.0 g/cc. The 4
U0 was assumed to be fully saturated.
2
- 2. All steel structural materials were neglected. The dryer driving screw was replaced by full density water.
- 3. The system was assumed to be fully flooded by water.
- 4. The net internal volume of the Holo-Flite processor was 107.62 liters.
The U0 was assumed distributed uniformly around the dryer driving 2
screw, which was modelled as a central cylinder occupying the l
remaining volume.
Accordingly, a minimum spacing of x - 2.0' will be provided for the centrifuge-dryer pail combination unit, giving a total exclusion area of 72 ft' for this unit.
This spacing is more than adequate, as the KEt10 nodel used was conservative. Af ter drying, the UO is 4
transferred to safe volume containers in the dryer discharge hood.
This hood is limited to one such container. These containers are moved to approved storage spaces to await additional processing.
Centrifuge supernate is discharged to a 9 3/4" diameter x 39" long overflow and filter recycle vessel.
It is then pe ped through a filter press for further clarification.
This filter press is limited to a safe volume and is assigned exclusion area spacing of greater than 9 ft'.
Solids from this press are treated in the same manner as solids from the centrifuge.
l
)
License flo. S!ll'-33, Docket 70-36 Revision:
1 Cate:
12/20/07 Page:
II.8-24
I 8.8 Waste Incineration The incinerator /3crubber system is used to reduce the volume of low level uranium contaminated waste with a maximum enrichment of 5.0% U-235.
The system consists of a gas-fired incinerator, an air-cooled heat ex-changer, an ejector-venturi scrubber and a packed tower scrubber.
The engineering flow diagram is shown in Drawing D-5009-1020. The system is located in area 240-3.
[
The equipment layout is shown in Drawing D-5009-2015.
Low level wastes are dispositioned for incineration l
after gamma counting. The wastes are logged in on the Incinerator / Scrubber Continuous Inventory Sheet and then subdivided into incinerator charges in the filter cut-up hood.
Individual charges are packaged in plastic or paper bags.
The typical incinerator charge contains about 10 kilograms of combustible waste and only a few grams of U-235.
The -
small size of the incinerator makes it necesr.ary to vacuum out the ash long before the safe mass is reached.
Operating procedures require removal of the ash when it reaches a depth of 3 to 4 inches (less than a safe slab configuration). fio significant ash accumulation has been observed in the secondary combustion chamber. Operating procedures, however, require inspection of the secondary chamber each time the ash is removed from the primary chamber. The probability of mode.'ation by water flooding is essentially zero.
f License tio. Sf4M-33, Docket 70-36 Revision:
1 Date: 12/28/87 Page: II.8-29
y 8.8 Waste Incineration (continued)
Charging of the incinerator is terminated when the inventory sheet shows that a total of 850 grams U-235 has been introduced into the system, or when the ash nears a safe slab depth, as stated above.
Ash will be removed from the incinerator via the vacuum collection hood, analyzed for total uranium and dispositioned for burial or wet recovery.
The ejector-venturi scrubber and its recycle tank are less than or equal to a safe diameter for 5.0% enrich-ment.
The packed tower scrubber is very similar to the scrubber used with the furnaces in area 240-2.
Thus, the same control procedures are used.
The scrubber liquor is sampled weekly and analyzed for uranium concentration.
The scrubber will be drained and flushed if the uranium concentration exceeds 1 gram per liter.
The heat exchanger, ejector-venturi separator box, and the packed tower scrubber are inspected at least annually for accumulation of uranium compounds.
No significant accumulation has been observed in over two years of operation.
Pressure indicators are located before and after each stage of the system. Operating procedures require frequent checks of these indicators to assure that the entire system remains under negative pressure.
I License No. SNM-33, Occket 70-36 Revision:
1 Date: 12/20/87 Page: 11.8-31 l
i
9.0 flVCLEAR SAFETY A!1AL_YSIS OF UF6- - UO 00t1VERSICtl 2
9.1 Reactor Vessel and Furnace a.
Description Cross section assembly dr>/.,ing of the vessel and furnace jacket is shown in Figure 9-2.
The elevation view of the UF - UO2 conversion reactor line is shown in 6
Figure 9-1.
The three reactor vessels, R-1, R-2, and R-3, are identical with the exception of the internal filters that are not included in R-2 and R-3.
b.
iluclear Safety Assumptions :
- 1) fiaximum enrichment 5.0%.
2)
Under process design (nonnal) conditions, Stim is only in the 10" diameter lower section of the vessel.
3)
Reflection as provided by furnace insulation; and vessel steel walls as shown'in Figure 11.9-2.
Reactor vessels are supported 30, 20, and 10 feet above the ground level; infinite water reflection is, therefore, not credible.
1 License fio. Stim-33 Docket 70-36 Revision:
1 Date: 12/28/87 Page: 11.9-1
9.1 Reactor Vessel and Furnace (continued) c.
Conclusions
- 1) Normal Conditions -
The SNM is in the lower 10" diameter portion of the reactors under normal conditions.
- 2) Accident conditions -
It is possible for the vessel to be overfilled by addition of excess process fluids causing SNM to be added to the 12 inch diameter upper section.
Since the process and these vessels are highly automated and instrumented this occurrence will be immediately detected and corrected by the automatic and manual controls.
Should corractive action not be successful, continuation of this condition will cause shutdown of the process and stop any further addition of SNM to the vessel.
It is, therefore, an extremely remote possibility that the vessel will be completely filled.
)
1 l
l l
i 1
l License No. SN!1-33, Docket 70-36 Revision:
1 Date:
12/28/87 Page:
11.9-2
~
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License No SNM-33, Docket 70-36 Revision:
1 Date:
12/23/87 i
Page:
11.9-4 i
t 9.1
- Reactor Vessel and Furnace (continued) c.2 Conclusions (continued)
However, a keff calculation has been nade for the R-2 Reactor as shown in 11.9-2.
The keff = 0.9510
.0055 c.3 Criticality Safety Analysis l
The following conservative assumptions v re used in the calculational model of the UF to LO conversion equipment analysis:
6 2
- 1. Reactors R1 and R3 were assumed to be filled in the 10 inch portion (i.e. no overfill) with dry UO at 2.5 g/cc density of powder and 2
5.0 w/o U' ". All structures consisting of.375" steel wall, 7.75" of 37.5 lbs/ft' firebrick insulation and.25" steel casing were included in the model.
- 2. Reactor R2 was assumed to be filled in both the 10" and 12" portions (i.e. overfilled) with saturated UO t 2.5 g/cc powder density and 2
5.0 w/o U* ". All structures consisting of.375" steel wall, 7.75" firebrick insulation and.25" steel casing were included in the model.
- 3. The cooler was assumed to contain saturated UO and to be enclosed 2
by a.5" external water jacket.
- 4. The silos were assumed to contain U02 with 5.0 w/o water. The.125" steel walls were also modelled.
- 5. The U0 blenders contained UO with 5.0 w/o water.
The.125" steel 2
2 walls were also modelled.
- 6. The 002 scrubbers assumed dry U0 with no external structures nodelled.
2
- 7. The R1 hopper was assumed to be filled with dry U02 and surrounded by 1" of water.
- 8. An external mist of.001 g/cc was assumed.
The KENO-IV code with Hansen-Roach cross-sections was used to determine the criticality of the system. The K-eff obtained was.9714
.0054 9.2 Cooler The cooler is an eight inch diameter with an external water jacket.
Eight inch diameter is safe at 5.0% enriched.
Reference:
Section 4.0.
License No. Smi-33, Docket 70-36 Revision:
1 Date:
12/28/87 Page:
11.9-5
i i
,~
9.3 Interaction of the UFr, - U02 Conversion Equipment These following interaction analys:s show that the reactors are the most reactive compoi, anis in the UF6 - UO2 conversion system.
Even though the reactivity analysis was done for 4.1% U ", the inter-action calculations are still valid and can be used for small additions to the systea.
The interaction of the conversion equipment has been evaluated by the solid angle method.
The total solid angle subtended at R-2 by other equipment is 0.70 steradiens which slightly exceeds the allowable solid angle of approximately 0.5 steradians.
Although the total solid angle slightly axceeds the allowable solid angle, the arrangement is felt to be nuclearly safe due to the re:atively low reactivity of the interacting units downstrean of the reactor.
Details of these calculations follow.
License fio. SNM-33, Docket 70-36 Revision:' 1 Date: 12/28/87 Paqe: il.9-Sa
9.4 Storage Vessels a.
Equipment Description
- 1) Storage vessels:
12 inch diameter x infinite length, 1/8 inch stainless steel wall thickness.
- 2) Milling equipment:
10 inch diameter x 2 foot high hopper; 10 inch x 1 inch deep mill; 5-gallon recycle pail.
- 3) Blending vessels:
14 inch diameter x 20 foot length,1/8 inch stainless steel wall thickness, b.
Nuclear Safety
- 1) Assumptions Maximum enrichment is 5.0%
Limited or no moderation Partial reflection 2)
Individual Units Individual vessels and units contain dry U02 under normal operating conditions and therefore are safe.
Further details of the control of moderation are set forth in the Nuclear Safety Analysis - Control of Moderation.
3)
Interaction The interaction of blenders has been evaluated by the solid angle method.
The total solid angle subtended at the most central blender is 1.123 steradians which compares with an allowable interaction of 2,16 steradians. Detailed cair,ulations follow.
i License No. SNM-33, Docket 70-36 Revision:
1 Da te: 12/28/07 Page: 11.9-10
a 9.6 Agglomeration Blenders a.
Description 1)
The 02 Blender is the centennost unit. All equipment will be separated by at least 4 feet.
2)
The maximum enrichment processed will be 5.0%.
b.
Assumptions 1)
Individual blenders are safe as shown in 9.6.c.
2)
Blender has optimum moderation.
3)
A reflector savings of 3 cm will be used to describe the unreflected case.
4)
The unreflected effective multiplication factors will be calculated using the data in NDE0-ll37.
5)
The blender geometry will be treated as a cylinder with a diameter equal to the blender diameter and the.ength determined by the blender volume and diameter.
c.
Effective Multiplication Factor Calculation - Normal Moderation The blender has a volume of 25.62 liters and a diameter of 9-1/4" I
(23.5 cm)
The equivalent height is t
_4 x 25620
_ 10.2480 h=
58.8 cm, r = 11.75 cm
=
=
"d2 535 x r 1740 Assuming the unreflected reflector savings is i
6=3cn 1
i license No. SNM-33, Docket 70-36 Revision:
1 Date: 12/28/87 Page: 11.9 17
e 9.7 Moderation Control r
The process of converting UF6 to U02 is performed in three closed systems.
Equipment for the first portion includes the attached UF6 cylinder, the UF6 to U02 conversion reactors, and the in process storage silos. A break in the system occurs at the milling equipment to allow charging of recycle material. The second portion includes the milling equipment, the dry blenders and breaks at the bottom of the dry blenders to allow charging the agglomeration V-blenders. The last portion includes the agglomeration V-blenders and granulator, both of which have openings.
Under normal operating conditions, moderation and moisture control are rigidly maintained to insure product quality.
This control also is necessary for material transfer through the various process steps. Both mechanical and administrative controls are used.
Assurptions a.
Maximum enrichment 5.0%
b.
Controlled moderation c.
Nominal water reflection i
License No. St.M-33, Docket 70-36 Revision:
1 Date: 12/28/87 Page: 11.9-26
Nuclear Safety (continued) a.
Reactors (
Reference:
NDE0-1963)
If one malfunction occurred allowing the 12 inch upper section to fill with SNM and water at the optimum moderation ratio, the effective multiplication factor would be k
0.9510
.0055
=
eff A second unrelated event such as substituting a more effective reflector would be required before accidental criticality could occur, b.
Storage Silos (
Reference:
NDE0-1137)
Two unrelated equipment failures would be required to cause water moderation. These failures are:
1)
The continuous drain on the 002 screw cooler would have to plug.
2)
The screw cooler water jacket would have to rupture, allowing the inleakage of water.
An additional misoperation causing the addition of a water reflector around the outside of the vessel would be required.
Approximately 5.75 cm of water wculd be required.
An equivalent man smeared around this outside of the vessel would contribute approximately 5.4 cm of water.
License No. SNM-33. Docket 70-36 Resision:
1 Date: 12/28/E7 Page: 11.9-29 4
y<<
s Nuclear Safety (continued) d.
Dry Blenders (
Reference:
NDE0-ll37) (continued)
- 4) Water could be introduced through the plant air system.
However, the following failures would be renuired:
Failure of the dryer Failure of the alarm Failure of water separator with the automatic blowdown.
The automatic blowdown on the blender air receiver would have to fail. This applies only to the blend air system,
- 5) Water could be introduced through the roof mounted vacuum transfer system blower. This renuires physical damage to the blower or accessories followed by forced introduction of water.
- 6) Loss of moderation control on recycle green scrap.
This material is certified eoual to or less than 5% water by process control and check, e.
Agglomerators This equipment it safe if optinally water noderated and un-reflected.
It is in a hood and is elevated off the floor, making floodino impossiblei f.
Granulators This equipment is safe if optimally water moderated and completely water reflected.
License No. SNM-33, Docket 70-36 Revision:
1 Date: 12/20/07 Page: 11.9-31
9.9 Slab Limits for Pellets The following analysis was done for a slab filled with 0.4" diameter pellets.
Pellets, when randomly loaded, pack to an average density of 5.95 gm/cc, with a sigma variation of 0.264, as detemined from a series of 14 measurments. Thus, at a 95% confidence level, the volume of H O to volume of UO ratio does not exceed 1.0 and from fig. I.E.16 2
2 of UKAEA Handbook MiSB1, the critical slab thickness is 6.2 inches.
Dividing by the safety margin of 1,2, results in a slab thickness of 4.8 inches.
The water to fuel ratio is actually lower than the above as the pellets are normally loaded on corrugated plates, which are stacked to obtain the stack height.
The sides of the stack are open in this arrangement.
License No. Smi-33, Docket 70-36 Revision: 0 Date:
12/28/07 Page:
11.9-33 i
NAR 111988 Docket No. 70-36 DISTRIBUTION:
Pending Fee File Ginny Tharpe, NMSS Combustion Engineering, Inc.
ARM /DAF R/F ATTN: Mr. H. E. Eskridge LFMB R/F (2)
Supervisor, Nuclear Licensing, DW/REJ/Com Eng Safety and Accountability P.O. Box 107 Highway 107 Hematite, M0 63047 Gentlemen:
This refers to your December 28, 1987 app'.ication for an amendment to License SNM-33 to increar,e the Uranium 235 enrichment limit to 5.0%.
You stated in your letter that the license fee would be submitted separately; however, as of this date, we have not received the fee. An application fee of $150 is required as specified in ll70.12(C) and fee Category 1B of $170.31,10 CFR 170, copy enclosed. Applicants in fee Category 1B pay an initial application fee of $150 and are subsequently billed at 6-month intervals for all accumulated NRC costs or upon completion of the review, whichever occurs sooner. The toIal fee assessed will be based on the actual NRC cost (professional staff-hours) to process the application as well as any contractual cost incurred.
Based on the above, please remit an application fee of $150 and mail it to my attention.
If you have any questions concerning the fee, please let me know.
Sincerely, Signed by:
Glenda Jackson Glenda Jackson License Fee Management Branch Division of Accounting and Finance Office of Administration and Resources Management
Enclosure:
10 CFR 170 cc: Mr. A. E. Scherer, Director Mr. C. B. Brinkman, Manager Nuclear Licensing Washington Nuclear Operations Combustion Engineering Inc.
Combustion Engineering Inc.
1000 Prospect Hill Road.
7910 Woodmont Ave., Suite 1310 Windsor, CT 06095-0500 Bethesda, MD 20814 r
0FFICE: ARM /LFMBi SURNAME: GJackson:rej DATE:
3// 0 /88
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