1967-08-15 – AEC – Historical Review of the Mallinckrodt Airport Cake


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REPOSITORY–~~ ….. .._..~RCOLLECTION–_;.,;;.;;~—
NO. ~~-..:~~if–….-~—FO~
ER ~(JeJT~I?I. J uly 26 , 1973
0)4P371’E#~#stfl?~ Sr.~
Dr. !·lilllic.:m E. ! btt
Division of Envirorlirental Control
Department of I:nergy
:·7a.shingta1 D.C. 20543
Dear or. ; iott:
-‘IUL ltriP – l -r-
4114 C1oarU …. “·,…, ·- … (31C)m-12111
Da ppa, Wt- CSIJt
01., ….
Enclosed is a copy of a paper pre ,:Jared by an AJ:X:. offi cial
in 1967, entitled “liistori cal r-.eviev1 of t he i·!al linckrodt
r.J.rport Cake . :• T’nis i s t he only v.rri ttcn info:t:.mation r
have been able to find on any Uranium nd.l l tailings left
in St • .WOuis.
If you should f ind any other infoi111ation on this subject,
I v.ould u?preciate yarr sen.d ing zre a <::q)Y . ..:.:..c.. .:..::» 1 • .P le~e feel 5:-ee to contact ne i f I nay :.>e of f’ l'(the~
ass 1s tance to yoo. r- n
N C!2
Sincerely, co < m ;i 0 - n -1(..~< -F.' ::0 J0<:1v . . • i-at .• 0 ~islative Assistant THIS WfATION'i:IIY rlt1Nl1:0 ON P'AI'CJII MADII. ¥UTH " t:CVCL&D l'lftlla ... .. HISTORICAL REVIEH · OF THE 1-'.ALLINCKRODT AIRPORT CAKE 1~ - .,. _' .. .. . In discussing the history of t~e airport cake raffinates, it is t necessary to define t hem and this has been attempted by the _ :_ simplified f~owsheet given in Figure 1. Mos t of the pitchblende ·; ·p r ocessed by K2lli::1ckrodt was obtained as a concentrate from the ' Belgian Congo in 1944 and was shipped to St. Louis from the Congo in 55-gall on metal drums. The pitchblende was digested in 56 per cent nitric acid (93-102°C) followed by sulfuric acid to precipitate the lead and radium \llhen the ore had a low sulfate content. The precipitate was removed by a string-di scharge rotary vacuum filter and was usually leached with sodium carbonate to remove · residual uranium. The sulfate cake was stored in a separate location. since the Belgians (African Metals ) maintained ownership of · the radium. These residues are•presently stored at the Lake Ontario Ordnance works at Niagara Falls, New York. Some pitchblende was al so processed at Fernald and a similar cake, still stored in silos at National Lead Company in Cincinnati, is known · as Fernald•s K-65 residue . Barium carbonate s lurry was then added to the supernate to remove the excess sulfate . The barium sulfate cake was removed by a continuous solid-bowl centrifuge, leached with sodium carbonate, and also stored in a separate area. · The supernate was made 1 ~ in nitric acid and the uranium extracted with diethvl Pt~~~- : 7ne uranium was stripped from the ether with dilute; nitric acid. ' In the first extraction colu::m a precipitate for.::~ed 'Which was, on ·· · occasion, ~emoved by a Sperry Fil terpres s . The Sperry Cake wa_s __ · · : found to be a good source of protactinL9m-231 and .~u~)processed ~ ' about 20 tons ( about eighty 55-gallon drums) and obtained approximately ~wo grams of protactinium-231. The supernate from the .Sperry Press and the aqueous uranium tails were de-etherized and tr~at ed with a hydrated lime slurry . The s upe~ a te frcm a continuous rotary vacuum leaf filter was di s charg~d to the river, and the limed fraction becawe the airport cake . The cake, up until 1960, was about 25 feec hig~ . and covered three acres. ··•· . . ..... ; ... ~ Organic I i ! HN03 Strip ! Urani uin Product Figure 1 Pitchblende Conce:ltrate v . ·. HN03 Digestion ~. H2so4 ll • Supernate ~ sa++ t Supernate I (J D iethy I Ether ' b . Aqueous --- ~ Ume ! Aqt·-•·->’)\
/14 ·us
1, ;.oo
Ta”ble I
Uranium Conten::
.-2 • 192
Pitchblende Raffincte1
Colorado Raffinate
Ba3 S04 Cake (unleached)
Barium Cake (leached) ·
Miscellaneous Residues
1 Estimated to contain
1,775,000 pounds Cobalt
• 2,085,000 pounds Nickel
1,098,000 pounds Ccpper
The i:”:~ten!: ~f tbe s~q~~-~~–fqr … Sale~~ was. tQ. allow private industry
to recover r.he valuable meta1.s: copper, nickel, and. co bait. -The
original request:”for bid offered the bidder several alternatives.
The purchaser could use the existing site for purposes of conca~
tra~ing and extracting a~y d~sired material or he could remove.
t~e residue from the site for processing or utilization elsewhere.
Th.e materials remaining after the purchaser8 s processing operanons
were over could be–disposed Ol: oythepurchase:::-at:l:n~\·]eldon
Spri-ngsdump s1._t_e_wnether ·or rioE pro.cessing .. was·-aone-ontfie-prE:-sc?nt
site o~ elsewhere. The Weldon. Spring·s–Quarcy~Dump-s1te wss a’ pit: ‘~
located in·St. Charles County on Ydssouri State Highway No. 94
. approximately five miles southwest of the \ve ldon Springs plant ~d ~ ~
approximately 30 rni~es frcrn the ai~port site. The site wa~ssible
by truck f~om Missouri State Route 94 and a spur track lead·
off the existing east way of the Atomic Energy Commission’s plant
track system providing railway access to the dump pi·t.
– 4 –
In response to a ~equest in 1960, Mound made a cost estimate
based on a pro1uction rate of 1>000 grams of thorium-230 per year
·~ o\·~!7 a two to five-year period on the assumption the airport cake·
. i~ 3t. ~.ouis would be available. Pre.;urnably it may have been
I POE5ib!~ for Mound to obtain the thorium waste stream from the
1 private contractor hot~ever tha cost: estimate was based on start- :~ ,
‘ j
. ~
ir.g with unprc~~s~~d airport cake~ Inclu~ing manpower, shippi~g)
material, and arnortiza~ion of .c~piLal costs over a five-year
period, th~ estimated cosc of the thorium-230 was about $300 per
gram. At ~hat time, Mound was also instructed to make a survey
of all uranium mills in the country to determine if other potential
sources of thorium-230·existed ‘from which this amount of production
could be economically rnaint?ined. ?his survey is compiled in
MIJ1 .. l439, ~’Survey of Sources of Ionium, Thorium-230,~’ by P. E.
Figgins and H. W. Kirby •
Mound received word in September 1960 that the St~ Louis Area
Office was recommending that the bid be awarded to Contemporary
Metals; a company having a “portable processing plant.,. The AEC
talked with them about their probable process which was to be
‘:. car:ied oqt on site and it seemed that they were interested pri)
mar~ly in the cobalt and nickel. However, they also would have
!I’ a s~de st:ream. for co!’lc.entrating scandium and expected thorium to
. go 1.nto that stream.
. .
Later in 1960, word was received that it was quite unlikely that
tn~ private cont:rac~ would be awarded since the United States
~~ Geologic·al Survey forbid the clumping of the sludges, processed ·
:1 or not, into the quarries in question because of the high proba;
bjlity of contaminating’the Missouri River shortly above the
intak~s for the. St. Louis City and St. Louis County water supplies.
Due to the many· problems, the St. Louis Area Office was contacted
by_Oak.Ridge Operations and asked to hold up awarding any contract
:o~ airport sludge until the long range requirements for thorium-
230 could be fixed.

.i Ic is not clear exactly what transpired at this point (perhaps
;,·Conternporacy Hetals .bankrupted) since the material was subse-
. quently obtain~d by Co~~~~!l~_al !·~nin_g .. _and 1-A’d.ll~_I}.g _ of- Chicago
…. 5
· .. ..
£or $:26,000. Co~tine~~al borrowed $2~500~000 from Cc~~arcial
D,iscount of Chicago to buy ar.d p::oces-5-t:Ee-reiidu·e-s~–using the
riSidu:3 dS security. Concir.2ntal moved the macarial from the
l., i..,r… port t-.1:1 ~Q.th-=.r_si te in sp.”buroaQ.J1?z_glwoo..Q_. ‘!his mova required
ten dump trucks for five monch3 and co~t Continental $100,000.
they were unabl~ to maintai~ ~h~ loan paym~nts while they were
·. ~oving the materia:, so Caillffic~cia~ foreclosed tha loan • .. …
. fbe Commercial Discount Corp_Q_r_— Organic
HN03 Strip

Aqt:ecus to
Adjus~ Addity
10 Stage t-~idi-Mixcr
<1 ..J>-,.
Ac.u eous

10 Stage Midi-Mixer
Return to Airport·
– HN03
— 0 rg~~~. ~ Scrub
.. )
Aqueous Product
. !’
. ‘
… -·-~ ….
A flowsheet for -t-he-·-Femo:v:al.-.of-.o.the.r … than the thorium and uranium
has not be.en developed and th_is. now see&7ls. a reas_onable thing to
do at this poinc:-‘!Ite-n-or-f’i””f·te·en-drums· ·o£ this r.~c:terial wera
processed to develop a flm~sheet for- the recovery of the thoriur.1,
uranium, copper, nickel, cobalt, selenium, and a ~are earth fraction,
it-migh:. be: possible to raduce t.~e ::adioactive contamin£”t.ion
of the final W8Ste raffinates such that they would be no problem
and could be disposed of alrno·s·t anywhere.
The 250 kilograms of thorium-230 contained in these raffinates
are more interesting than ionium per se; cost estimates are already
in existence for irradiation to protactinium-231 and subsequent
irradiation to uranium-232. Mound has twelve thorium-230 slugs
on hand that were irradiated in the }ITR at Idaho Falls in 1960.
It· ·is planned to process these capsules in order to develop a flowsheet
for the production of protactinium-231 •

August: 15,. 1967
– 8 -.
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