ML19305A512
| ML19305A512 | |
| Person / Time | |
|---|---|
| Site: | Crane  |
| Issue date: | 05/29/1979 |
| From: | Kelber C NRC OFFICE OF NUCLEAR REGULATORY RESEARCH (RES) |
| To: | Murley T NRC OFFICE OF NUCLEAR REGULATORY RESEARCH (RES) |
| References | |
| NUDOCS 7908230006 | |
| Download: ML19305A512 (1) | |
Text
.. _
O pg0 l
me-IEMORMDUM FOR: Thomes E. Murley. Of rector Division of Anactsr Safety Ansaarch FRON:
Charles M. Kalber. Assistant Df rector
~
kr Advanced Reactor Safety Researth
SUBJECT:
REPORTS MD M PRODUCTICR MD RECOMIDIATION FOR TMI-2, OM 0 2
2 i
l i
The attached nports have been prepared by L. N. RTb and J. T. Lartfas.
I believe they are responsive th that aspect of Commissioner tiltasky's I
questions you asked th.m to stub. The chief conclusions are: deflagratten is more probabh than detonation and neither is likely under poobable i
TMI-2 conditions. Allo in the TMI-2 eonditions. there was no pctantial for b u'.14-up. Steve Kent (CA) has asked for a package of matarial en the eral questicos of it and 02 mroation. I suggest that we send him the attachment as part of s,uch a package; er you might prefer to put i
together scaething more completa.
I i
t Original signed by i
Charles N. Kelber Cherles N. Kalber. Asafstant Df reeter for Advancsd Asactdr Safety Arssarch Dtviafon of Asactor Safaty Resaarch cc: D. Heatson (w/anc1). RES/Wt:R I
Dccut Iw so-3?c
'\\
j i
79082 3 J
i
_.m s
'o UNITED STATES m o '0
, g$ wi' g NUCLEAR REGULATORY COMMISSION D
wAsmoTow. o. c. aosas oa
\\f. M.o#
MAY 2 51979
?
"O ~9 I
Lp s g a
o L.
~
MEMORANDUM FOR: Charles N. Kelber, Assistant Director for Advanced Reactor Safety Research i
Division of Reactor Safety Research FROM:
Louis N. Rib, Special Assistant Advanced Reactor Safety Research Division of Reactor Safety Research
SUBJECT:
RESPONSE TC 70MilSSION REQUEST FOR INFORMATION ON THE POTENTIAL FOR 0, ACCIDENT ACCUMULATION IN THE REACTOR VESSEL DURING THE THI-2 The response to this question is addressed in three parts: (1) Net production by radiolysis in the reactor core of H and 0 ; (2) the 2
effect of the environment (coolant chemistry, co power, P,T) on 0 production; and (3) the potential for 0 buildupinthebubblein$he reactor vessel.
2 1.
Net production.
In PWRs the net production frcrn the radiolytic process is suppressed by maintaining a concentration of H2 gas in solution in the primary coolant.
In Reference 1 Hochanadel showed that H and 0, in water a't 25'C to 2
250*C are recombined by gaerna radiatiog/Xg maintained 0, concentratio Reference 2, p.
3', states that "H concentrations as low as 6 cm 2
at 0.01 to 0.02 ppm with water temperatures in the range 300 to 380*F."
This temperature range is appropriate for the period of the TMI-2 incident whare the primary coolant terrcerature reading was 280*F and the "H
bubble" was of concern.
2 2.
Environmental effects.
Nevertheless, if one assut.es: an opening i." the primary coolant system such that the water level in the reactor vessei was down to the outlet pipe; no H, gas in solution, and, the core is at a 10N(th) decay heat level, theh, KAPL calculated a radiolytic gas (H, and 0 ) generation rate of less than 20 scf/ day (Reference 3). Therefore, 9this value represents a maximum generation rate since we are aware that an excess of H7 was actually present in the primary system.
If this quantity were generated in a boiling region of the core, gas could be stripped out of solution. However, above the boiling region, the gas may be redissolved.
l in which case the recombination would remove all the 0.
Or, O m l
be removed from the gas stream when the 0 sweptbyhofmetal(fr)ight l
surfaces.
2
]
Ln g
rp
\\
~
Charles N. Kelber MAY 2 ; 1979 3.
0 Build up 2
If some of the 0 managed to reach the gas bubble at the top of the reactor,couldt$e0 e ncentration build up to approach the deflagration 2
or explosive limits? Aside from what the limits may be (this is addressed in the following section) KAPL evaluated the H and 0, recombination 2
rate under the following conditions (Reference 3):
a' gas phase containing H, 0,,, water vapor and a gansna field strength of 6,000 r/ hour at atmosphere p essbre. The calculated rec mbination rate is of the order of 1,000 scf/ day. The experimental data base for this calculation is given in References 3 and 4.
It is expected that as pressure is increased from atmospheric pressure to 1000 psi, the recombination rate will also increase. This assumption is based on data in reference 4 which shcws that increasing hydrogen concentration increases the H -0 This assunption requires experimental verificat$on. recombination 2
rate.
Another factor which would increase the recombjnation rate is the much larger gama field in the reactor-vessel ( 10 r/hr). Therefore, the 1000 scf/ day recombination rate is considered to be a very conservative value.
The recombination rate thus is much greater than the very conservative radiolysis rate. Therefore, any 0 which reached the gas bubble would disappear rather than concentrate.2 This conclusion precludes the possibility of a H explosion in the gas bubble region of the reactor 2
vessel.
CLAN Louis N. Rib, Special Assistant Advanced Reactor Safety Research References 1.
C. J. Hochanadel, Proc. Intern. Conf. Peaceful Uses Atomic Energy,
- 1955, 7_, 521-25 (1956), "The Radiation Induced Reaction of Hydrosin l
and Oxygen in Water at 25'C to 250*C."
l 2.
ORNL-4173, " Water Chemistry in Pressurized and Boiling Water Power l
Reactors," G. H. Jenks and J. C. Griess.
l 3.
KAPL - Evaluation of Radiolysis Concerns Associated witn the Three Mile Island Unit-2 Incident, dated May 1979.
4.
C0010321. "Recmbination of H and 0 i Yapor under the Influence of kadiati$n,n the Presence of Water
" Drs. Benjamin and Isbin, University of Minnesota, July 1965.
L
. - = _
, e /.'
ic' 1
KAPL Evaluation of Radio]ysis Associated Uith The Three Mile Island Unit-2 Incident By J. C. Conine D. J. Krem cnhoek D. Enanuel Logan 8
May 1979 0
mO hv'{'
O 9
O.
Y,c d.
s g
m.
El
?.
/
\\
UNITED STATES
(
NUCLE '.R REGULATORY COMMISSION
{
I wAsumcToN, D. C. 20656
\\'.o /
MAY 2 51979 MEMORANDUM FOR: Charles N. Kelber, Assistant Director for Advanced Reactor Safety Research Division of Reactor Safety Research THRU:
/M[ Louis N. Rib, Special Assistant Advanced Reactor Safety Research i
Division of Reactor Safety Research FRCM:
John T. Larkins, Nuclear Safety Engineer Experimental Gas-Cooled Reactor Safety Research Branch Division of Reactor Safety Research
SUBJECT:
RESPONSE TO C09tISSION REQUEST FOR INFORMATION ON FLAMMABILITY AND DETONATION LIMITS FOR HYDROGEN /
OXYGEN / STEM-MIXTURES AT ELEVATED TEMPERATURES AND PRESSURES In response to a request from Cmmissioner Gilinsky on the flamability -
and detonation limits of hydrogen / oxygen / steam-mixtures, T..Murley, Director, Division of Reactor Safety Research requested that I see what information was available on this subject.
I have reviewed some of the literature and have had conversations with several experts on'this subject. The limited literature search perfomed by me was primarily on selected publications covering the years 1935-1972. John Lunsford of Los Alamos Scientific Laboratory has been reviewing the literature frcm 1970 to present. Neither of us have perfonned a detailed search; however, if this is desirable. Lunsford would probably not mind continuing on this project. None of the infomation reviewed by us contained data
-(vapor); however, there is enough separate infomation at either e,/0 /H 0 specifically at 1000 psi and temperatures between 280-550*F for H lehated 7
temperature or pressure and for H / Air /H O (vapor) to develop scrne 2
2 limits.
1.
In a hydrogen rich system at ambient conditions 5-6% oxygen would be required for deflagration (burning), however, this lower limit may not give a coherent flame (inccinplete burning). Also, deflagration would require a strong ignition source at the lower limits. The effect of elevated temperature and pressure would be to lower the
/
oxygen limit, however, 5% oxygen is probably still close to the
/
minimum.
,/
v
,, /
l E
Charles N. Kelber MAY 2 51973 2.
The detonation limit at 1000 psi and 290-550*F is going to be between 9-12% 0, for a hydrogen rich system with the 9% lower limit unlikely without a strong ignition source. Knolls Atomic Power Laborato.y report (reference 8) gave a lower limit of 10% 0., for detonaticn in a hydrogen rich system at 550*F. The report Bid not mention the pressure at which the experiment was run.
3.
There is probably no effect of water vapor below 75; however, as the amount of water vapor increases above this value, the probability of an explosion decreases. Flamability limits will not be affected until you get to concentrations above 25t water vapor. At 60%
{
water vapor, the probabi;ity of burning hydrogen and oxygen is 1
zero.
j 4.
It was noted by several experts that if oxygen were being generated I
in a hydrogen rich system, that deflagration would probably occur l
prior to detonation if an ignition source were available.
I have listed several of the more important references at the end of this report. Also, a list of references covered in the literature search by Mr. Lunsford is available.
In conversations with experts in this area, it was pointed out that there are several facilities available for experiments on hydrogen deflagration and detonation including one at Ohio State University.
It is recomended that if more exact information is required in this area that an experimental program be initiated.
9 T/ d4 John T. Larkins Experimental Gas-Cooled Reactor Safety Research Branch
References:
1.
G. W. Keitholtz, " Annotated Bibliography of Hydrogen Considerations in Light Water Power Reactors," ORNL-NSICl20.
2.
B. Lewis and G. von Elke, " Combustion, Flames and Explosions of Gases " Academic Press, New York, 1961.
3.
D. M. Kuhn, F. L. Daley, et al, " Explosion Limits in Mixtures of Hydrogen, Oxygen, Steam and Helium." ORNL-Y-731, 1951.
4.
R. L. Matthews, "Ex;,losion and Detonation Limits for an Oxygen-Hydrogen-Water-Vapor-System," XAPL-6564, June 1966.
l l
l l
~
l
3-MAY 2 51973 Charles N. Kelber 5.
B. C. Slifer and T. G. Peterson, " Hydrogen Flamability and Burning Characteristics in BWR Containments," NED0-10812, April 1973.
6.
H. F. Coward and B. W. Jones, " Limits of Flamability of Gases and Vapors," U. S. Bureau of Mines Bulletin 503, 1952.
7.
T. H. Pigford, " Explosion and Detonation Properties of Hydrogen, 0xygen, and Water vapor," (ORNL 1322) August 1952.
8.
J. C. Conine, D. J. Kromenhoek and D. Emanuel Logan, "KAPL Evaluation of Radiolysis Associated with the Three Mile Island Unit-2 Incident,"
May 1979.
e e
v.