ML20004C329
| ML20004C329 | |
| Person / Time | |
|---|---|
| Site: | Crane  |
| Issue date: | 05/29/1981 |
| From: | Hovey G Metropolitan Edison Co |
| To: | Barrett L Office of Nuclear Reactor Regulation |
| References | |
| LL2-81-0124, LL2-81-124, NUDOCS 8106030187 | |
| Download: ML20004C329 (9) | |
Text
e Metropolitan Edison Company y
- '1 7
Post Of fice Box 480 gj
- g[
Middletown, Pennsylvania 17057 717 944-4041 May 29, 1981 LL2-81-0124
-e TMI Program Office 2
~~
lE Attn:
Mr. Lake Barrett, Deputy Director g
e U.S. Nuclear Regulatory Commission M
4 Ei=:
c/o Three Mile Island Nuclear Station m
Mg Middletown, Pennsylvania 17057 "32
$C E':
3-
Dear Sir:
iG Three Mile Island Nuclear Station, Unic 2 (TMI-2) 5 u
C)
Operation License No. DPR-73 Docket No. 50-320 Submerged Demineralizer System During' discussions with members of your staff, you r : quested that we provide our estimate of the number of filters to le generated
, g Ff
,g during SDS operations. You further requested that we estimate y' C
~F 1
the total amount of radioactivity to be deposited in the filter s
vessel as well as our planned method of disposal. This estimate h
[g
[
v should include tranturanics lor".ing.
You requested that we provide you with a description of the filter dewatering technique.F JtjN 0 2 M "
1 u.s.Nucuaa non^ross ;
'Ca*'5'"
This letter responds to that request and is intended to address those concerns for prccessing sump water except for transuranics b
.Y dp) /
loadings. RCS water processing'as it relates to filter loading g
will be addressed at a later time. Transuranics loading of the filter will be addressed when we address criticality concerns, by May 29, 1981.
l The planned method of disposal of the prefilter c.nd final filter
)
is to ship tiem to shallow land disposal. From current in foma-tion on suspeuded solids in the RB sump water, see ORNL/TM-7448, and the elect.ntal and radioisotopic distribution in these sus-pended solids, wc believe that the operating limit on SDS filters will be mecnanical performance (i.e., differential pressure) with little radioactivity deposition. It is anticipated that these filters will be suitable for shallow land burial in commercial sites. The filter devatering technique is described in the System Description Docu=ent, submitted to you on May 11, 1981.
\\
010603 0 FC}
~
-. _ =
1mp my a
)
g
[
.~L.
H. Barrett',
i We-have-prepared our estimate of ; filter loadings while processing Reacto".'
' Building sump water. Estimates 'cencerning filter. loading.while1 processing of
- Reactor Coolant System' water are provided below.
~
The SDS filtration system is composed of two series filters, a 125 micron filter element' preceding a 10 micron filter element. The filters will.be installed in the "B" Spent Fuel Pool to take advantage of the radiation shielding provided by the. pool water. In the process flow stream, the filters are upstream of the. tank farm to preclude the deposition of a significant amount of solids into the-tanks.
We intend to. provide flow from the Reactor Building' sump to the tank fare
~
using a floating pump that' takes suction just below the water ' surface.-- This flow scheme has many advantages, one of which is that it is expected to provide-the capability to' fill the tank fans tanks with little solids entrainment. in 'the flow stream. Furthermore, it is estimated that particles greater than'10 r
microns have settled to the bottom of the sump, leaving 'small amounts of particu-
'lates for entrainment in the SDS processing flow stream. Because of the expected low concentration of particul.tes in.the process flow stream, we estimate that l
one prefilter and two final filters will be used for filling the - feed tanks l
until the pump nears the botton of the sump. As the pump nears the bottom of the sump, the influent solids concentration may increase such that an increased number of filters may be required.-
It is important to note that the design intent of the SDS filter inspalla: ion is to protect the downstream ion-exchange media from any possible significant particulate loading. These filters are not intended for use in 9emoving sludge from the sump. Until that sludge can be better characterize'd, in' terms of its quantity and physical and chemical properties, no decision can be made as to-t adaption of the SDS, or -use of any other system, for its removal.
We have performed an analysis of the radiological locding of the expended filter vessels. Using the assumption: that the filter volume completely. fills, the contents of the completely filled filter (worst case assumptions) would contain less than 1 curie in either the prefilter or the final filter. This radionuclide loading corresponds to a loading concentration (assuming uniform dirtribution) of less than. yCi/ml in both the prefilter and the final filter; they' are auitable for shallow land burial. See attachment 1 to this letter
}
for specific assumptions used and the basis for this estimate.
4 t
i Our current intended mode of operation for processing RCS water requitec' that
)
let-down to the RCBT occur prior to initiating influent flow to the SDS. RCS water will then be transferred to the tank farm, on a batch basis, prior to SDS processing.
h I
1
~A i
~
~_
,j j
~
"EL k
4 j
L. H. Barrett 1 1
l Using preliminary result's of RCS sample analysis for suspended solids provided to GPU we estimate that processing RCS water through the SDS filters will not contribute to the deposition of solids in the filters. This is based on the fact that analysis indicates that there are no particles greater than 5 microns in suspension, 14.7% of the suspended solids are in the size range of 1.2 microns to 5 microns, and 85.3% of the suspended solids are in 'the size range of 0.45 microns to 1.2 micror.s.
Based on this information it is anticipated that suspended solids is the RCS Some of will not be deposited on the SDS filters but will be passed through.
these solids will remain in the tank farm tanks while it is expected that the remainder of the solids will be retained on the zeolite beds.
We have analyzed the potential for degradation of the zeolite beds as a result of deposition of these small size suspended solids onto the. bed. Our analysis indicates that these size solids are too small to contribute to - plugging of the top layer of the bed and too large to enter the :eolite pores. It is believed that there is sufficient void space in the first zeolite bed to accom-modate the entire quantity of solids estimated (0.129 mg/ml). Attachment 2 to this letter provides the basis for the above statement.
is to be noted that this analysis is based upon one suspended solids analysis It of one RCS sample.
It is not known if the sample is representative; the RCS is stagnant. Furthermore, the analysis is performed for solids that are suspended in solution and does not account for non-suspended solids in the RCS let-down flow r.tream. However, it is believed that non-suspended solids in the RCS flow streas will remain in the RCBT due to the low flowrate from the RCBT to the tank farm; particulate matter will probably not be entrained.
1 I
Should you wish to discuss this matter further, please contact Mr. L. J. Lehman, Jr.
of my staff.
i Sincerely,
,e
/"l
_o +4 t
/w-f G. K. Hovey Vice-President and Director, TMI-2 I
l GKH:LJL:be I
Dr. B. J. Snyder, Program Director - TM1 Program Of fice cc:
I i
M
~
I
~~
7
-w oui.
-y+r
..,-emr-
.-m
--ew---,%,.
---.,-,--.n,--_y.
-.w,we-rs-=-
w..
4 V-Attachment ~1 Page 1 of 5
'l Estimate Filters Wich Will Expended 'if Solids Settling Occurs.
Assume the. solids settle according to Stokes Law:
V = 2 ga2(d -ds) t 9 n.
'W ere:
V= Settling velocity in cm/sec 2
g= 980.621 ca/se~c a= Radius of falling sphere in ca.
3
. d = Density of-sphere in g/cm t
3 d = Density of Medius' in g/cm 2
-x n= Coef ficient of viscosity in poises (gps /cm-seci
+
Determine Density of Species Wich Will Settle Out:
ORNL-7448 states that the precipitates ar'e predominantly Fe, Ni, Al & Cu hydroxides and.'some finely divided matter.
Cu (OH)
= 3.368 g/cc Density A1 (OH)2 3
= 2.42 Ni (OH)
= 4.15
-Fe (OH)2 "34 2
Solids content of samples has Sr activity.
Sr0
= 4.7 g/cc Density SrSO4 = 3.96 'g/cc Density Sr(OH)2
- 8H O = 1.9n ' g/cc Density Sr(OH)2
= 3.625 g/cc 2
SrC03
= 3.70 g/cc i
l
- e.
i
'S
~
g, j"'
.c
.4 Page 2 of 5 Since Sr(OH)2e8H O and A1(OH)3 are least dense of species and slowest 2
to settle out, use these two as basis for settling calculations.
Calculate Settling Velocity, V, for 0.lu, 1.0u, 10u, 25u, 50u, 75u, and 125u,
- Diameter Particlew Of 1.90 g/cc and 2.42 g/cc Density.
V =,2 ga2(d -d,)
i a= As Required (S e Below)
I 9n g= 980.621 cm/Sec 3
dg= 2.42 or 1.90 g/cm 3
d = 1.10 g/cm 2n= 0.00S904 g/cm-sec for H 0-2
@ 250C Values:
-Particle Size Diameter (ce)
Radius (cm)=a 125 g 0.0125 6.25 X 10-3 75 g 0.0075 3.75 X 10-3 50 8 0.0050 2.5 X 10-3 25 g 0.0025 1.25 X 10-3 10 p 0.0010 5.0 X 10 5g 0.0005 2.5 I 10-4 1g 0.0001 5.0 X 10-5 O.1 g 0.00001 5.0 X 10-6 i
.A
.e.7 Ta t
=,,,.
l
i Page 3 of 5.
SETTLING VELOCLTIES FOR 2.42 g/ce' PARTICLES:
. V.42. = 2(980.621) (a)2 (2.42.- 1.10) 2 9_(8.904's 10-3) 3.23 z'104 (a)2
. h.42
=
V.42 = 3.23 x 104 (6.25.x 10-3)2 = 1.26 cm/sec 12$
2 1
-V.42 = 3.23 x 104-(3.75 x 10-3)2 = 4.54 x 10 ca/sec 75p 2
V.42 = 3.23 x 104 (2.5 x 10-3)2 = 2.02 x 10-1 cm/sec
.50 p 2
V.42 = 3.23 x 104 (1.25 x 10-3)2 = 5.05 x 10-2 cm/sec l-25 g 2
V.42 = 3.23 x 104 (5.0 x'10-4)2 =~8.08 x 10-3 cm/sec 10 y 2
~V.42 = 3.23 x 104 (2.5 x 10-4)2'= 2.02 x 10-3 cm/sec 5y 2
V.42 = 3.23 x 104 (5.0 x 10-5)2.
8.08 x 10-5 cm/see 1 p' 2
V.42.= 3.23 x 104 (5.0 x 10-6)2 = 8.08 x 10-7 cm/sec 0.1 p ;
2 i
f l
pe" en e
M-
.g L
g
(
,__-r
,,_,,-.__.._...,.,,.....m_,_.,~,...-,_-,-
.,...#_.--m..-.,.,,....+~,mm,
l attachment i Page 4 of 5 l
1 SETTLING VELOGTIES FOR 1.90 g/cc PARTICLES:
2(980.621) (a)2 (1,90 --1.10)
Vg,90
=
'9 (8.904 x 10-3) 1.958 x'104 (a)2 Vg,90
=
- .V,90 = 1.958 x 104 (6.25 x 10-3)2 = 7.65 x 101 cm/sec -125 1
V,90 = 1.952 x 10 -(2.5 x 10-3)2 = 1.22 x 101 cri/sec 4
75 y-t V,90 = 1.958 x'104 (2.5 x 10-3)2 = 1.22 x 10-1 cm/sec 50 1
V,90 1,958 x 104 (1.25 x 10-3)2 = 3.06 x 10 2 cof,,e 25 1
V,90 = 1.958 x 104 (2.0 x 10-4)2 4,90 x 10-3 cm/sec 10 y 1
V,90. t,958 x 104 (2.5 x 10-4)2 = 1.22 x 10-3 cm/sec 5g 1
V.90 = 1.958 x 104 (5.0 x 10-5)2 = 4.90 x 10-5 cm/sec 1p 1
V.90 = 1.958 x 104 (5.0 x 10-6)2 = 4.90 x 10-7 cm/sec 0.1 p ;
1 t
E P
t l
i a:-
=_
7 i
s
)
a Page 5 of 5 SETTLING TIME; T= 8.2 ft. (2.54 cm/in.) (12.in/ft)
+
T(hr.) = 6.94 x 102 1
V
.T.42(Hr)
V,90 Tg,90(Hr)
V.42 Particle Size 2
2 I
125 p (7.65 x 10-1) 9.07 x 10-2 (1.26) 5.5.x 10-2 75 g (2.75 x 10-1) 2.52 x 10-1 (4.54 x 10-1) 1.53 x 10-1 50 g (1.22 x 10'l) 5.69 x 10-1 (2.02 x 10-1) 3.44 x 10-1 25 g (3.06 x 10-2) 2.27 x 100 (5.05 x 10-2) 1.37 x 100 10 y (4.90 x 10-3) 1.42 x 101 (8.08 x 10-3) 8.59 x'100 5g (1.22 x 10-3) 5.69 x 101 (2.02 x 10-3) 3.44 x 101 1
(4.90 x 10-5) 1.42 x 103 (8.08 x 10-5) 8.59 x 102 0.1 (4.90 x 10-7) 1.42 x 105 (8.08 x 10-7) 8.59 x 105 Based on the above conservative analysis, using the surface suction pump to pump sump water through the SDS 125 prefilter and 10 p final fitter for feed tank fill, 'the majority of the sump v-ter can be filtered using only one prefilter and one final filter until the sump pump nears the RB filter. At this time the possibility exists that additional solids will be entrained in the liquid flow' stream for deposition on the SDS filters. Estimates of filter usage under these conditions cannot be made because of the uncertainty of assumptions that night be used.
a 7*m
-s.
~
^
4 e
-e,
..-ww,.,.., -.
3
--,,w.~
,e
-.,,._v
,_..m,
-.u,
.,,s,-,,..,
9 a
s.
tr
/ '
[
Page 1 of 1 iLUME.0F SOLIDS IN 90,000 GALLONS OF RCS, BASED ON SUSPENDED SOLIDS ETED BY EXION OF.129 ag/mi AND ASSUMING (CONSERVATIVELY) A DENSITY
,1 g/ml. :
3 3
.129 og x 3785 31.x 90,000 GAL x 1-x 1
x cm x
m 10 c,3 6
3 1 /*1 al al GAL 10 mg 8
= 4.4 x 10-2 3
3 0F ZFOLITE, ASSUMING 30% VOID THE VOLUNE OF VOID SPACE AVAILABLE IN 8 FT SPACE:
8 FT3 RESIN x.3 FT3 VOID SPACE x.028317 m3
= 6.8 x 10-2.3 l-I-
FI3 RESIN FT3 o
NO. OF SDS LINERS REQUIRED:
4.4 x 10-2.3
=.65 3
6.8 x 10 4 m 1
1 l
eene
,W
~-
~
r
-m
,m
,gg.
w._,.,y.,..,,___,,w,
,-y e-.,,+.,,yvs