QRN FEC!..'ICAL INFORMATION . DIVISION e s ¥-12 TECHNICAL LIBRARY 3 Document Reference Section ; Muc-LA0-28 LOAIY COPY ONLY | This document consisis oi < peges and _Dmege @t fi—rei Do NOT transfer this document to any other ; - - pcrson. If you want others to see it, attach their NO-__i__.__Q-"-____,_K__CQpiQS, Series ) nomes, rcturn the document, and the Library will grrange the loan as requested. ML UCN-1624 - & POy Nt ¢3 5-60) NOTES CN MERTING OF APRIL 28, 194/ iy ervte g T | . ST - ' N 9:00 - 10:= 209-LEck PPN . ER22al s woad @ e ,;.':; ] Preseat: Fermi, Allison, Wipgner, Smyth, Szilard, Xorison, Vsbscn, Feld, e ;{ Hogness, Young, Veinberg, Creuis, Coopar, Vernoa, Chiinzer Er?nt | RO The first specler was Mr. P. Yorrizon; his camuents follow: I9 N i we view the chain reaction merely s a source of uwnsoscializsd energy,?i‘b, g N goes directly into competition with the many eccisting large scals prAge™ G N movers and fuel sources. Eccnonics are then paramomnt. It is My. Morrison'€r ' opinion that we should not move in that divection for sone time to come, _ but should attampt vo exploit the particular properties of the chain re- ' acticn as a conceatrated source of a highly special form of energy. Power « ' simply as Ilw hours shouid appear at most as a by-produci. — ET Y LW ) R4, %m“’- Tae following data was gathered from the Buresu of Mines bulletins CLASSIFICATION Gy T . §@ and other sources and correlated by Mr. Morrison. | ) % In 1941 the avérag= Jezxly powsr procuced by the major scwrces = Qi was as follows: 2 ! , A A Water 25 x 10° K Gas und Pe‘troléum Producfs | ’3!.;0 x 3.0‘6 w ' Coal : L70 % 105 kv - The first item covors mostly. goverimcat §1Q Privete utilities and private { indusirial power developients. OFf ths power produced from the sscond fuel N sourcs, aboub LC{ vms from gasoline in all its uses. Of the power pro- " ~duced from coul, sbout 107 was used in public uii i X4 ilities, about 103 for 1, coke and cheanical uses, abovi 20% for railroad transposrtation, and the S, balance of akoub 6CX for other miscellencous uses including domestic end Andustrial fuels. O tho above total figures for the world povier production, the U.S. consursd about 355 of the coal-produced powsr and sbout 603 of the petrolewn~produced powsz. Cost figures for the above power, while not on a strictly com- parztive basis, are interssting. The figurss below are £1l per negavatt houx’, - Goveradeny aydropovar - . H1.20 Privete hydropowsy - - 2+00 to 2.50 Host officlcat coal-steam plants - 0.80 (‘{:; Cityv constmo -~ 20.C0 e Large dndusesd 2 conewter (fiva poway) - 4..00 ;_{,’{m?«f,’: d Rjvlian - 4,00 v el (Znergy, not mechenical power) . ' H*O.0D TNT - $2+66 Hi-octane gac - b0 50 Lotor fuel - v 2.00 e first item 1s vased cn the cost of the power at Boulder Dam ot the bus- oar face on a g\eru cd consurction coxminuously threouchout the 24 nour sy ond - includes thc cosv of ths or:.b:mal eqguipneat, maintenance, ebc. Tha £iguee for the coal-steam. plant is based on the fuel cost oaly and does not include the eowloment, maintenancs, ete. As Mr., Szilard poinved out, thess two camnot be compared end, as Mr. Fermi observed, it ls the 80¢ figurs of the coal-steam plents with which we must compebe in the productien of power. . As Mr, :.Iomson noved in a recent memorandun, the mpv'o:d.mate atundance of tubealloy and thorium in the top crust (5 to 8 ku thick) of thoe sarta is as fol.l.omr Tubealloy 14, '—"- 2 ppuw- (i'oimd mostly in graniite and docs not include sends, etc.) .- Thoriva =~ 12 x L ppn (found mostly in sedimentary vocks) “he most officlend golci extraction plant yet consbrucied has besaa aba.e to dlz the rock, crush it, treat it; sitc. to recover the gold for about $7-CJ per ton. Crushing rock requires about 100 kw hours per ton when the rock 1s reduced to parvicles of aboub 1 fn3 in size. Therefore, r. Morrison -estimates that we could afford to woric ths rock for power (based on using - the 25, not the 28), if necassary, providing the sbundance of the tubsalloy was not less than 5 vo 10 ppm. It has been estimatved that there are about 10t% - 1015 tons o; natural tubealloy to be found in xock in the earthl!s crust and about 105 tons in sea water (the concentration in sea water is about 10~9 pms of tubezlloy por gm of water). " The richast occurences of natural tubaalloy in the world are at the following locatlons. All figurcs are very rough estimatec based cn dnconolete and often reluctent surveys by the producers. All tomnage Pigures ure tons of tubeslley and not ore. U.s. (mainly Cclorado vanadium ores or Carno- tite, having a content of about XI tubu- elloy. Letimated st 3,000 tons of tube- alloy available in 1925.) - " about 5,000 tons in sight. . Czech {(also about 1% content) sbout 1,000 tons remaining. -3 =~ Congo (of five sites total, one was estimavcd in 1925 at not less than 5,000 tons of about 5,000 toas ore having 20 tubealloy content) in sight. Canada (although other deposits undoubbedly exist, the inown devosits containing 20 to 50% tubealloy conteut ors have) about 5,000 toms. Russia (1 to 2% tubealloy content Carnotite not less than vanadium ore depasifs) | 3,000 toas in sight. Togual about 20,CC0 taons of tube- alloy in sight. . . A similar table of the distribution of ‘thorium throughoui the vorld follows. Thls is found almost entiraly in menszite sand hawving about 5 to 11% thorium content. - . U.S. (mainly in North Carolina with a small | amount in Icaho and Florida) about 1,000 ions. Prazil (on the coast) | : about: 8 ,000 toms. British India ‘ about 150,000 tens. Netherland East Indies may have about 5,000 tous. If we were to use the entire U.S. and Canadian resources of tubeailoy (10,000 tons) using a ¥ of 0.9 amd wiilizing only the 25 and . not the 23, we would have an equivelent replacement factor of only nine months for the total powse consumpvion of the U.S. opr about ten yesars for the hydropower. ' o The second speaker was Mr. Szilerd who continued his discussion froa the previous meoting. He recapped fivst the thrse possibilitios as hs saw then. . (1) Unseparated tfibealloy'-—)h‘) production (2) Enriched tubeslloy —49 productlion (2) slow chain reaction (b) fast chaln reaction (3) Mriched tubcelloy—-~3no 49 production e — -~ - Lyt o0 capture remains constant. Szilard therefore assumes that, in a mixburs ol 222 and Plutonium, EV, = 1.2 x 2.5 = 3.0 neutrons emitived per thermally fissicnable atom destroyed and this would mean that thers is a net gain of one thermally fissionzble atom per similar atom destroyed. Referring to item (3), Szilard emphasized one possibility, i.e., the burning of Plutonium in a slow recaction and absorbing the neutrons by - bismuth to give Poloniuvm. Of the heat dissipated when Plutonium is des- troyed to give Polonium, only about 3% would be stored in the Polonium. However, this energy will be available for use free of ‘6’ radiation and could be used for driving airplanes, etc. In the discussion following, Ferml questioned the estimated value of L/, = 2.5 on ths ground that it might be too optimistic and pointed out that there 1s a long range future in developing the full utili- zation of 28 and thorium. Viigner questioned the feasibility of the rotating disc arrange- ment described at the previous meeting on the ground of poisoning and . questioned the 4} year investment return. He felt this would probably be more nearly 10 to 20 years by which time, as Mr. Morrison suggested, we nay be burning water. After discussion, Szilaird expressed his view that item 2a is of more immediate concern than 2b. Mr. Morrison suggested that more work should be done on the nuc- lear development of thorium bscause of its greater availability and also suggested experiments to obtain Wipg and other useful constants, M. Ohlinger explained very briefly an outlired program, of which a copy is attached hereto. This program for :consideration of future trends in the laboratory work, is a compllation of the independent results of the "homatiork" recuested at an earlier meeting. It has bsen assembled to give a majority concensus of the classification of possibilities. In general, the outline is first divided into three main groups based on the use to vhich a pile would bz put. Thereafter, the potent- ialities are subdivided for easy consideration. An open discussion oi' thls outline will occur al the next mesting on Fridsy, May Sth. I. POWER PRODUCTION (49, 25, or 23 consumed) A. Purnose of power (in order to determine following) 1. Physical size and mobilitv a. Large stationary piles (slow chain react. or group of fast chain react.) such as for central stations b. Mediun mobile (or sta.) piles (slow chain react. or group of fast chain react.) such as for boats or locomotives c. Small mobile pilés (fast chain react.) such as - for plenes or cars 2. Power output range, e.g. L] a. over 1.06 Iew b.. betwean 103 - 106 Iewr C.. less than 103 kv B. Diilisaticn of Energy 1. Direct a.. Klectrical removal (including thermocouple type) b, Working fluid absorbing heat directly ' (1) Direct liquid vaporization in plle o to dperate turbine, etec. (2) Gas cooling with or without ges ° turbine (3) kndothermic chemical reactions, e.g.5 20 -~>05 4 2o 2. Indirecct Lnergy removed by ocirculating a. the metnl b. the moderator (if any) c. the coolant IT. ISOTOPK PHODUCTION (49 or 23 produced) (Since its purposc is well defined and there are no limitations on slze, lack of mobility and power produced, oxecpt by the ogerating potentialities of the design chosen, these factors arc not outlined heras. A. 49 Production l. Slow chain reaction (thermal neutrons) using normal U a. Homogencous piles moderated vilth (1) P9 (2) P-9 5 H0 b. Helterogeneous piles moderaved vith (1) Graohite - inprovement in oneration and vilization of present pilec (X end %) and design new im- proved piles (2) P~9 %Also require a separation pro- cess Lo recover P-9 (3) P-9 % 520 (4) Be (5) BeO c. Cooling accomplished by moving (1) the metal (UF6, molten U, solutions) (2) the moderator (P-9, P-9 4 H,0) (3) a separate coolant (H20, P-9, liquid Bi or Bi-Pb alloy, diphenyl) 2. Enriched piles (enriched with 49 or 25) &, Slovi chain reaction as outlined above b. Fast chain reaction as outlined below 3. Fast chain resactions (no moderator) a. licmogeneous pilcs b. Heterogeneous piles c. Cooling accomplished by (1) Liquid Bi as coolant (2) Liquid Na as coolent (3) Using U molten and movinp it - B, 23 Production 1. Roflcctors ‘ -t ae P | N e N Cormcnt: IP rower procuced In maliing £9 cin v wnld practicalli s, oiils con- stitutes nnethor case, = a combination of Y oa! IT. o ¢ v - TTi. RODIATION SQURCE (High levels of intensity) (Since the purpose is well defined and size, mobility and povier preduced are not criteria, they are not outlined here. However, such a pile must be flexible with the ability to reach high levels of intensity and expose mater- jals or takc measurements with ease. TFlux: and not total power inportant here. HMost suitable of piles defined in II to be chosen as experimental machine. Routine metal removal is not important.) PROBLTAIS CO:ZION TO ALL PILLS (or a large number of’them) 1. Shielding 2. Reflectors