Report No. 39

C W C T E R I S T I C S AND UTILIZATION OF FLY ASH

Produced by

FAIRBANKS AREA POWER PLANTS

I?. C. J. Lu

P, Dharma Rao

MINERAL INDUSTRY RESEARCH LABORATORY

University of Alaska College, Alaska 99708

January 1971

The authors wish to espress their gratitude to the C i t y of

Fairbarks Xunicipal U t i l i t i e s Sysstfm, Golden Valley Electric

Association, Unit& States Army Fort W a i n w r i g I h t Pager P u t and the

~ n i v e r s i t y of Alaska P w e r Plant for their help i n collecting fly

ash saxples.

?hank are also due to Mr. Richard Hamilton, I(wd Materials

IaSoratory, Dep-t of Highways, S t a t e of Maska, for the

analysis of the fly ash samples presented in Table 1of this report.

Tins authors also express their apsreciation to Dean Earl H.

B e i s t l i i e , Dr. Mmld J. Cook and Dr. m e s t N. Wolf f for their

interest in this project.

m ~ o : i - . ~ ~ Page i

OF ~ L ~ T S

LIST OF ~ L E S ii

JwmG- iii

iv

I- ~ D V C T I O N

Smm C U ~ ~ I O N ~ Y S S

m- mTm f i m s FDR FLY -0us mus-

LIST OF T I W E

PAGE

1 X * Y Y S I S OF FLY ASFI P I U I D m TN BE FMmYiiS

2 SPECIFICRTIOXS FOR FLY M H usm AS AN ~DEXTUIE IN FORZEW CETCENT aXClXTE

3 QL-STICS OF THE POIm PLfiLVS ANALYSm

4 FLY ZSB PGODUCPIOV AM) COLLECTION SYSmJS

5 PXlDLCTiOX PXD CORISuP.~ION OF FLY PSI1 IN THE U. S.

iii

Fly ash is a nau minesral cmm3ity which is a by-procluct

cSCLili~~ecl frm burning pulverized coal in a - 7 s plant. It has

th2 physical aqd dlemical properties of pozzc~lan. a silicews

and/or silicebus-alrmrinous material w i t h no in4erent ca~a t i aq

character, but which, in the presace of water, w i l l cabins w i t h

calciuin oxide at ordinary twperatws to form c m t mxpm&.

It largely consists of solid or hollav spherical particles of

siEcx3us a d a lminous glass, with sllall m u n t s of '&-walled,

multi-faced p lyhdrons of high iron content and k q u l a r l y shapd,

relativrtly porous carbon or carbon-coated particles. other minor

ccr;pcnerts of fly ash include: magnesium oxide, calcium oxide,

alkalies, sulfur trioxide, and other elements in minor quantities.

11. SA.WE C O ~ I a ? Am ~ Y S I S

S a q l e s of f ly ash w e r e collect& fmo f o ~ paver plants - -\

sewing F a i x b a d s and the g e w a l vicini*, AZ1 four p r x v e r plants

receive coal frm the Nenana coal fields. The four plants are:

G o l h V a l l e y Electric Association, Mine Nouth P a i ~ Plturt at Healy;

university of Alaska Power Plant; C i t y of Fakbanks, Municipal

U t i l i t i e s Pcwer Plant; and th2 Fort Wain~(~~ishht Pcwer Plant. p s

s q l e s were analyzed for S O Z t A1203Fe203, Ng Or S 03, noisture,

loss on ignition and surface area. Table 1 show the analysis of the

four sanples.

1,

DL? to tho cliffereaces in physical and chsrcical proprt ies of f l y ash £ran diifurfnt sources, individual specificatioils have

km set up by vcuiolls organizations. For exarple, Philadelphia,

Chicago, ~ z t r o i t , X:ew York, ard F l i n t have their a m fly ash

specifications; and S t a t e H i g h a ~ a y Depar-ts, the U.S. Bweau of

Pbl ic m&, and the U.S. Bureau of R e c l ~ ~ t i o n h3~s their am

qixifications for f ly ash Used as construction materials. O t h e r

orgmizations such as the A=ican Society for T e s e !aterials

- 1 I U. S. Engineers, Veteran's Amhinistration, =son

Electzic Institute (EEI), an6 Varicus consulting f b cumentLy

aze w o ~ P A g on nw ~~pscifications a d d e s epplic&le to f ly ash.

kl&'~ , Comecticut, Georgia, ma Kentuc* have ~ i f i k ~ o n s

for the Qse of fly ash in Portland c w a t concrete used for highway

purposes. Illinois, Indiana, Kansas, Maryland, Michigan, New Jersey,

N o r t h Carolina, and South Caro1ir.a have s~ecificatio~'1~ for the use

of fly ash as a mineral filler in bitminous mixtures. Virginia end

~ y l v a n i a , since they forbid the use of f ly ash, have no specifi-

cations. Illinois and Virginia pe2mit the use of fly ash in limefly

ash-q3ega-k -e for soil stabilization of b i t ~ ~ i n o u s roads.

ASDd has trm cannittees (C-7 and C-9) dea l i~g w i t h the s p e c

ifications of fly ash used as pozzolan and as fine aspegate. Tnere

are presently sevet ssecifications designated by ASDI.

1. ASDf C311-53T JPethocls of sqling and test ing fl:y ash £0 use as an admixture in Portland anent corlcrete.

2. ASn.1 C311-61T Tmtative m e t h c d s of sailkg ma testing : a5h for =e as an a a 3 w e in Portlaad cement concrete (&vision of ASTN C311-53T:

3. AST?4 C340-55~ S p c i f ication far Portland-pozalan cement.

4 . RSTN 6359-54~ Spcification for flv ash for use as an admixture jn ~ 0 ~ 3 a n h cenm-t: concrete.

5. ASTT1 (2350-60T Tentative spscificatian for fly ash for use as an a h i x t u e in Portland cment ccmncrete (Revision of AS734 C350-54T)'.

6 . . ST?-I C379-56T Tentative spcification for fly ash for use as Pozzolanic material. with l i m e .

7. ASWL C379-65T Tmtative spcifications for fly ash for use as pzzo l an i c material w i t h l ine (Revision of FSTv1 C379-56T) .

bBst of the specifications mention& in the above paragra-ph

are for f ly ash used in the ce i in t and mncrete markets. Fly ash

as a pzzolanicladditive is required tm have a m b h u m of 40 psr cent

silica and three @ercent mgn2sim oxide, a maxi~nm of five pzr

cent weight loss on ignition, a two to t l e e &r cart maxirmnn misturk

a n t e n t , 0-12 per cent retained on #325 sieve, and a 2800-3000

2 art /gm alaine Specific Surface rating. Table 2 lists the i m p r t a n t 1

specifications designed by ASn4 and the Bureau of kcl&tion.

Tmm 2

SP~IFICA!TIONS FOR FLY ASH AS USED AS AN

Al3ammE IN PO^^ mlENT EL^

Specification A Specification B

SiOZ +A1203+ F ~ ~ o ~ (Minum~m) 70 % 75 8

Magnesium as MgO (kuimum) 5 8 5 %

Sulfur Trioxide (Mainrum) 5 8 4 %

Alkalies as N a p ( m u m ) 1.5 % 2 %

Loss on ig?lition @ 75Q0 C (Maximum) 12 % 5 %

Moisture C o n t m t @ 105O C (mimum) 3 % ~ o t specifid

Mean particle diameter, microns ( m h ) 9 % Not specifid

SO-: Specification - A, AS?M C-350-60T, 1964.

Specification - B, Bureau of Reclaimation Specificatiors

Tli2refore, if f l y ash is to partially replace c m t in th=

major concrete market, it shodd contain 70 to 75 per cent of con-

binc4 silica, ~ ~ a , and iron o x i d s in order to p e t the f ly ash

specifications i n road paving, structwal concrete, and concrete

prducts . Research efforts on the ut i l iza t ion of f l y ash have not as yet

dsvelc2d all of the facts -essary to s t a t e the ~rcpex specificatior

for fly ash in various markets. Spscificaf5ons should represent a '

cqroniss bebreen the disire of the purchaser fcpr a product that .

mets his specifications, and W type of f ly ash available, This

problem has k e n exminsd by Snyder: (i, p. 35-1, 38)

"Although it is possible for producers and c a s u m r s of fly ash to reach agreement concerning the suitability.of a given f l y ash for a given use on &basis of present specifications, mither party's interests are fully S e n r e d by present specifications-

From the viewpoint of the puchaser, there is an UnInmm &-re of r i s k that a fly ash which meets specificati0n.s may not prove to be satisfactory in service.

Fran & vim-point of the producers, ~e spscif icatio,ls may well be mre res.trictive than is trrarranted leading to the rejection ' of f l y ash that would have been p e r f o m satisfactorily in service---"

IV. RX!l%TIAL MRiRRZPS FOR FLY ASH IN W O U S lN3USTW3S

% follcwing is a w r e h ~ i v e list of industrial &kts .

for f ly ash f r ~ ~ n current Literature, although very few of these are

applicable to th& Fairbanks =area at this t i m e .

1, ?.Lir,eral Incius tries a, Iron and steel indm'cry

1) Slag-fly ash aggregate 2 ) Raw material of ixon oxi& 3) H i l d abrasive in rrietal polishing 4 ) Fot~'1d1-v sand

4 .

5) B i n c l z in pelletizing iron ore, replacing scats bmtonite - - - -

b. Aluninm Industry 1) Raw materials for al- 2) Fo*;u:dry Sand 3) Abrasibe for polishhg alminuin products

c, Refrac-tory Indusky 1) Brick 2) Tile 3) 0 t h ~ ~ cer&c products

d . Glass Industrv 1) Raw nuterlal for colored glass containers 2) Abrasive in glass finishing

e. C m t Industry 1) Raw materia in cemMt mmufaccturing 2) Pozzolmic additive

f. Petrolem Industry 1) Pressure grouting 2) C e i i a t i n g of oil well casings

g. f i n o r m e t a l industry 1) Raw raterial for Germanium 2 ) Paw ~mterial for G a l l i u m

h. Coal Itlining 1) 1 % ~ dusting, prevention of explosions and fires 2) Nzu'lralizing acidic mime water

i. ~4isccllar.eous 1) Heavy rnsdia se?aration agent 2) Minaal fillers 3) MineYal wool

2. Chs i -ca l Indus t ry a. P a p r 14anufacturing

1) Mineral filler 2) Neutralizing acid waste liquids

b. Wber manufacturing 1) b l in s r a l filler

c. Plastics and paints 1) Illinera1 filler

d. O t h e r s 1) Filtration agent 2) Neutralizing agent

3. Construction Industry a- Coacrete for r-d paving and mass coiicrete projmf

(dam aid bridges) b. Concret- h7 --'-- C- ~ c r @ h ~ - i n ~ tile and o&r concre te prducts

,-..-- L 5 - - -- - -t~-~&aLLun

£. Fly a s h - h aunr-at-n

$ULC

b ~ l ~ ~ ~ i aggregate

- --3=J--yu-

9- Fly ash-slzg agyrqB+- h. Fly ash liqhi~.p;r<.-4 - i. Grou t j . Filler in w a l l boafa ---LL -

-

k. Land fill .u, p~q- . a m roofing matexials

4. Agriculture "4

='4 a. F e r t i l i z a b. Filler 6. lhsecticiifmc

- - ------" d. Trace elenat source

OF FLY ASH . *.

.:< - ' 7

t&ay research efforts have damnstrated that f ly ash h a a w i

variety of applications in the various industries. Fly ash has - . . - -.

+? P qali:ied as a rax material, additive, subs t i t u t e or for o m fom -1 .. -4

of ut i l i za t ion in the construction, iron and stesl, al-m, . .

cera-nic and chemical industries, and in agricuLtrue. The major - * - ..

reasons for using f l y ash in the abwe fields are the diversified r. . -

mture of by-product ash. and low cost of ash k h i c h eva-y !i ,. . . . ma.ke it raketable. AS

Th -u?es of f l y ash thus pan ha r n r 3 7 . . , c - 2 r r .. - - .q nological ~ f o m c e and econcmic reward~ frm fly a ~ h p i ~ ~ . *

1. Fly ash is a bv-nrodt~r+ mew- :- -- - > . L-- - - - - - r d.4+-d~ ss rlu IIUUI~ 0r quarrying

2. The particle size of fly 3-L :- rr-- . . .whiny or grinding in 11:

eliminate

3. DUE to it pozzolanic propa-, f l y ash can h bridely used as a 1-z+i mterial in c m - t rranuf ciuture. - - -

.. 4. ale vriGo ran,, of c~iqgoeition of fly ash =tends its

. . ~ s c s in the installic, aramics ch5niczl inclustrizs as rsw mkzrials .

5. Tce whumt: carbon of f ly ash could save as "hilt-in" fuel aad save cost in th2 ~nanufacture of f l y ash ag- gregates, bricks or tiles.

6. Fly ash may iiizove final prcducts, giving such qualities as higher strength, h x z porosity, stronger &ses and cornrrs in concrete blocks, less cracking, and resistance to s a l t and sulp-hte w a t e r s in grouting.

7. Thc f ly ash na.rI<~ts are generally close to payer plants since bth are located in p p u l a t d areas.

8 . The high alkali chxacteristics of f l y ash can be ! utilized as a lm-cost neutralizing agent.

9. Sone high silica f l y ash msy be used in mild abrasives, fou~dry sands and in glass manufacture.

10. Tine m-ine3 percentage of silica, alur~ina and iron oxide in f l y ash is so high as to make it useful as a mineral Tiller, filtration agents, etc.

11. Fly ash is resdily available in qyantity.

V. AS3 PkE9DVCPIC2J PND VPILIZRTION IN THE FAIR2?2'VXS E m

The demand for electric pmEr in Fairbanks has been grming

steasily at the rate of abut six per cent a year siF--- &- the 1950"s.

A t present, all the electricity in the area of study is supgLied by

coal-firing plants. There are four instiWons sqplying energy in

the region, n m ~ l y Golden Valley Electric Association, (GTi?) . m.

Wainimight (military) . Fairbanks Municipal U t i l i t y S y s t ~ m (2.1. U.S. ) ,

and the Univsrsity of Alaska. Table 3 s h m the capcity of electric

peer ~azera t ion of each i n s t a l k t , type of fue l , location of

p i e r plant aid apgroxkte clistence to the city cent- of

: Fairbanks.

Capacity (kw)

Pheral/Fuel

Location

Distance to C i t y C e n t e r

G.V.E.A. M.U.S. MILITARY U. of A. 22,000 8,500 27,000 1,500

Coal, Mine C o a l P ~ u t h

Coal Coal

Healy Fairbanks Ft. Wainwright College

within less than 10 less them 10

The production of i l y ash is a function of the q~u~nt-ty a d

ash content of the ma1 burned, and the efficiency of &h collection.

The recw,, of fly ash is d e p e n d a t upon the of coal b m s ,

ths variation in burning process a d the type of ash collection

s- .~s te~ , whether zsd?:,anical or electrical. Table 4 shavs t\e

estimated f l y ash production per year of fnu' power plants m J a - -

study, t h e mthcd of ash collection, relative efficimcy in recovery

02 f l y ash and ash disLmsal mthd and exprimes in utilization

of each pcr~'sr plant.

FLY AS13 PR3DUCTI:ON A ! ! CO-TQN SYSTEM!!

F l y Ash Prod. approx, ( E s h t d in short tons pcr year.)

Type of Clcmbustion system

mlative Recovery

Ash Collection Systm

Ash Disposal

Utilization

G.V.E.A. M.U.S. MU;mARY

pulverized stoker f u e l

average low

stoker

low

mechanical mechanical mechanical (most bottcm ash)

v?et wet truc1:

s m inland fill

lm

mechanical

d T

scene inland fill and road mintenace

A very Limited amount of fly ash is k i n g used in *I

~airbclrks area for land or structural fill and road mhtenancc.

, - The pstential uses of fly ash, parkicularly for the fly ash

.-

p-~cel by the G .V.E.A. Mi, -mum ~ o . . r e r plant would he:

1. Concrete mixes

2. Soil s tahi l izzt ion

4. Structural fill

$lass concrete project (airport, &n md ma- f;lr;l;+i*-\

Grouting or wsll-casing cment.

AS an inqr&e.i.it in concrete mixes, f l y ash can be used in - -

m l m t s f m 100-150 pun& cuhic yard of concrete. &ady-mix&

concrete, concrete blockc. r?re,+w----~ - - t - -- -- , ~ - 3 CL-~K;I ma precast cancrete, mass

concrete ~ r o j e c t s and high- co~stntct ion and a t w a n c e represa9t

many attractive fields open to the ut i l izat ion of fly ash.

Soil stzibilization alone a u l d p r o m y absorb th- "'mjor part

- of raw f ly ash. A mile of road base pay utilize h u t 500 toM of - .

fly ash and in g u l u a l 'sli&rnuay construction, about 600 to= of fly

ash co'ald be put into ths paving of each mile of single lane highway.

Therefore, a bo-lme highway for 100 miles could &sorb -6 220,000 tans of ash.

Fly ash is used in oil well casing cerent in the lmre states;

its pssible ap$iwtion to the Alaskan market is obvious.

Alaska Wrts over 20,000 tom of c m t a year. If 20 4 4

cent of ceiient is substituted by swif ied fly ash, it \-muould < -

rzm a m k e t for 4,003 tom of fly ash.

0 t h ~ ptent ia l markets in the field of winter road s t a h \

i l i za t ion m d control of thawing stre% in spring tim-, oo~rld

only be evaluatd by further research.

1966 1967 1968

PlPduction (&IS) f l y ash . 17,123,144 18,409,854 19,813,747 bottam ash 8,065,683 9,131,453 7,259,212 boiler slag ---------- --_-_---__ 2.554,569

Tota l 25,188,827 27,541,307 29,627,528 Total Ash 3,050, 669 3,794,714 5,194,016 Consumption (tons) f ly ash 7.94 8.29; 9.6%

% ut i l izat ion b o t h ash 27.0% 25.08 25.0% boiler slag _--_- ----- 57.8

Total ~ n s m p t i o n to praluction 12. 0 13.8 17.5

Source: National Coal Association

J)

~ l y ash from four coal-firing p a 7 e r stations in the ~ a i r b m k s

vic ini ty was intifstigated during t h e study. The w m plants u n ; l s

stu?y rmge f ran 1,500 ki lmvat ts to 22,000 k i l a t t s , m d c0mms nore

UICV- G50,000 toils of coal annually.

TIE p r o l i m i n q investigations shm72d that the ccmpositi0~1~

OF f l y ash collect& fro2 each of the plants, although they do not

m e t .G!E.J specifications, other ptential uses of this fly ash

are promising.

Total production of f ly ash in the Fairbanks area is =ti-

nted at mre than 13,000 tons per year. SO far, very limited

m u n t s of f l y ash are ut i l izer l in the area; ace for land or

structural fill and a very L i t t l e i n road maintenance. Wa~ever,

thse ace pt&'Lial uses for fly ash such as ready-mix mncrete;

mass concrete projects, road construction and grouting.

Since f l y ash is a by-product f r o m coal firing p ~ e r stations,

the future of f l y ash is closely tid to the continued use of c m l .

as an energy source i n p d e r gemration. The threat of c a p t i t i o n

£ran fuel oil or natural gas has been greater since the developnent

of the xorth Slope oil fields.

utilization of f l y ash is determined by many factors such as

quality and specifications, the effort devoted to market develo-zent,

and sales promtion. In the imnediate future, if any market develop

in Fairbanks, it \ v i l l be concentrat& in the Construction and bdustq.

1. B1xsk , E.C. ara3 Chapan, J.F. (ed.) , Padern marketbg S k a t v : ' I a r ~ s ~ d UniversiQ Press, Cambridge, Mass. 19 64.

2. Cap?, J.P. a d FaSer, J.H., Utilization of fly ash, wpm ~resentd a t the industrial coal conference, A p r i l 13-14, 1966: ~nivers i ty of Kentucky, Lexington, Ky., 14p. 1966.

3. Cap, J.P. Faber, J.P., Technology and economics of fly ash utilizzitition: Paper prese?ted at U e AIME annual meeting, February 28 to ?bxch 1, 1966, New York C i t y , 7p. 1966.

4. Cap?, J . F . , Fly ash ut i l iza t ion, paper presented at the 1965 i n d s t r i a l coal conference, Octobzr 13, 1965: Purdue Y m r i a l Center , Lafayette, Indiana, 1 1965.

5. C a p , J.P., Research program seeks nav uses for f ly ash: Electric l ight a ~ d WJ-, 3p. October 1964.

6 . coal Age, Tn+ coal picture - 1965 to 1966: C o a l Age, p. 75-79. February 1966.

7. C o a l Age, Fighting waste with w a s t e might be one way of &scribing what appears to be a significant n w use for f l y ash: Coal Age, p. 51. June 1965.

8. Cwl nining aid processing, pzct signed for w e s t e m coal-fired electricity: I n d u t r i a l ris~s, p. 13. Jline 1966.

9. cockreell, C.P., Shafer, H.E., Jr., and H U I ~ ~ ~ ~ S , K.K., Fly ash- based structural mterials: Recent deveIomts wing the WW-CCR process, paper presgnted at the UaE annual meet+: N ~ V york City. ,* February 28 to March 1, 1966.

i - '

10. Consol Xews, Fly ash can be an asset: Consol News, p. 1-6. May to June 1966.

7

12. Edison Electric Inst i tu te , Proceedings : s e a n d fly ash utilization 4 spps im: Pittsburgh. March 10 - 11, 1970. -2

13. En?le. M.D. , et al, Fly ash ut i l iza t ion , prh.3 mvers camittee: Ne.61 York, 99p. February 1958.

I

14. F m , J.H., Ca??, J.P., and Spncer, J.D., USEX IC 8348, Procedngs: first fly ash uti l ization s ~ , p s i u ~ , Edison Electric I n s t i t u t e , i\lational Coal Associztion and B L V ~ ~ U of Minesr p. 345. 1967.

15. Federal p:ier m ~ s s i o n , Annual &prt 1965. Janzary 10, 1956.

G a i s , G.C. , P0.q~-p lan t ash - the coal industry's hidden 02prtunity, pa= presented at the 3JbB annualmeting: XWI York C i ' q , 17p. F&ruaq 28 to March 1, 1966.

Match, EI .P . and Conncrs 7 D.N . , U s e s of fly ash in the ~4- electric pmer systm: Pa-pr presented at the AIiG annual meeting, Ee.$ York City, 1lp . February 28 to March 1, 1966.

Jarrigz , A. and D a r q u e s , V. , L i n e cements fixation by f l y ash, Rev. E a t e r . Construct. Trav. Publ., ,m. 594, pp. 144-8, 1966. (:in P r a s \ )

Jarrige, A. andl D a r q u e s , V., Fly ash util izatioa in France, Flame et therm., p. 185-189. A u g u s t - Septerrber 1960. (in ~smch)

20. Jxrige, A. and D a r q u s s , V., Industrial uses of fly ash: d t a l *search, Chim. et Ind., p. 185-189, Febma~'ry 1963.

21. Jamrek, W. G. and Schanz, J. J, 7 Jr . , B i t m i n o & c-1 coA'lsqtion, Cca1 Age, 7p., r q k i n t . May 1960.

22. J o ~ ~ s o ~ , G.E., KunCia, L.M., and Field, J .H. , U s e of coal and fly ash ks adsofbents for r-ving organic contaninants from s e c m d q

? -, municipal effluents, Ind. Eng. Process Design Develop., vol- 4, ::I no. 3, p. 323-327. 1965.

23. Katx, Jacob, T'ne effective collection of fly ash at pulverized coal- fired plants, 3. A i r P o l l ~ ~ t i o n Control Assn., vol. 15, no. 11,

.p. 525-528. 1955.

24. Lu, F.C.J., Potential m k e t s for fly ash in the U.S. , a Ilrrdel for market research and deve1opent: M. Sc. thesis, Departxent of Minezal eco~omics, Pennsylvmia Sta te University, 146p. SepL@= 1367.

25. Matrns, r.!., Sand-f ly ash brick, Materials Research and Standards, vol. 4, no. 8, pp. 427-430. August1964.

26. 14,innickf L. John, Fly ash meets l ighb~eigh t aggregate splcif - ications: Brick Clay Record, vol. 146, no. 4, LOP. 15)65,

27. PLin?ick, L. J O ~ . Characteristics of lightweig5t aggregate produced frcii fly ash: Paper presented at the mid-year meeting of the expanded clay and shale assn. , Na.7 Yorl;. August 6-7, 1964.

28. 1-Lirhg Ilagazi~e, Fly ash may curb mine fires, p2- 475. ~ecer[!kr 196E

29. EQrphy, E.I.I., bhgnusm, M.O., Sudsr, El., Jr., and Nagy, J,,-use of f l y ash for r a t e filling of underground cavities and passa5e- ways : LSBI FU 7214 , I.Jashin.fton, D.C. , 27p. & c a b s 1968,

30 * XaLdofial Coal Assn. , Ssnator Byrd surveys f ly ash prospects : Coal N w 3 , no. '. 3814, p. 7. Sept&w 9, 1966.

31. Lovell, H.L. , Spicer, T . S . and Homherger, R.L., Fly ash properties and beneficiation rnethds: PaF presented at the annual mting OZ ,912.EJ !dm Y~rkf 26~. F & m q 16 - 20. --.

32. Orrlce of C o a l Research, F<TW, Coal - associated flyash, Coal - associatd minerals of the U n i t e d States, section 7-DJ p. 89-10Zr C o a l R & D ReAmrt nmber 8, E X , 131p. Junz 1965.

33. Pearson, A.S., Lightweight aggregate from f ly ash: Civil 'Er,gineerhcf: New York, Pp. 50-53. Septeier 1964.

34. Pemqlvmia S t a b Universip, -9n investigation 0.3 potential markets fax f l y ash: Project rept: to the PEI, The Departmat of ILqsxal Econanics,'i%e Peiiylvania S t a t e Universiw, 69p- J m e 1965.

35. Pit &?d qu3rry, Western f ly ash Ltd., p. 160- Jan- 1970.

36, Scha£fer, S.G. a6 Noble, P,.TV., T e M q u e s for utilization of f ly .

ash: Fm. Chm. Society - D i v . Fusl Chemistry, vol. 10, no. 1; Pa-= preseqted at the rnesting on EWch 22, 1966, pp- 73.80. I

1966. -

2 .." - 7

37. Shafer, H a q f E., . Jr., Cockell, Charles F., and Leonard, J.N., -1, Flv ash brick, progress report: presmted at national ax1 association technical sales conference and bitminous mal research, Inc., Annual Meeting: Pittsburgh, Pa., 13p. Se?t&er 14-45, 1966.

38. Snyder, M - J , and Nelson, H.W., Final re-mrt an a critical review - '

of technical information on 'd..e u+trilization of f ly ash to prime mvers cornnittee, Ec3ison Electric Ins t i tu te , Columus, ahio: 2 Battelle l4emsrial Xnstitutcr 106p. July 13, 1962. . 3

1

. . '"i 39. Snyder, M.J., .These, A . J . , H u n t e r , R.I., and Gluck, P., Progress . f

,i repst on f l y ash utilization research program: EEI bubletin, ..- i pp. 38-42. Febv~ary 1966.

20 . .

5 .,: * Z:F rple ..- ....-

-a;$ - * ..- . .. * i;.

40. Srlvdsr, Y.J., Rose, .I\..J., Hunter, R . I . , Gluck, P . , Progerties " and uses of f l:y ash, B a t t e l l e Technical Revie:?, the Battelle

. K~mrial X~sk i tu te : C o l ~ ~ , Ohio. m. 14-18. F&mary 1964.

41. S~wZzr, F.J., R=se, A . J . , Hunter, 3.I., Glud;, P., am2 I?dsm, - Il.I.?. , A critical revim of technical infomation on the . utilizatioa of f l v ash: Unpblished pap=, final rep* to the Priine KnverS m i t t e e of =I, the Battelle :+!=rial Ins t i tutet CoLm5us, Ollie, 106p. 1952.

I

42. Sto-hz, R.%. and C d i i n , W.B., Fly ash as activated carbon: U.S. pta?t 3152,985 (cl. 210-40) to W. Va a l p and Paper Co, 6p. Octo3er 13, 1964.

43. GBM, I4imrals Yearbook, Annual Volmes, U.S. Bureau of ~ ~ s s .

44. US%): ancZ II'I! R a e a r c h Ins t i tu te , Processings: s k d minasal waste utilization symposium: Chicago. E-ch 18 and 19, 1970.

45. Vszina, J.A. and ~XT.V, W..A., Ths preparation of c-cia-grae vanadium pentoi5d-z f ran boiler f l y ash: Can dzp-t mins and tech. S w ~ y s , !nines Branch, Tech. Bulletin, T.B. 63, 13p. 1965.

46. T.?att, J.D. and Thorne, D-J-, Pozzolanic propcrties of fly ash, zs d e t h ' t d by crushing-strength tests on lire mrtars ; Journal of 4pplied Chemistry: mndon, vol. 15, no. 12, pp. 595- 604. 1965.

T.?att, J. D. and Tnolme, D. J. Pozzolanic pro-~rties of f lv ashes as determind by o\ernical m ~ & : J m d of hppl&d Ci~cmistry: Tandon, vol. 16, no. 2, pp. 33-39. 1966.

FKllia.%, 5.1;. , Jr . , Investigation of c m t - f 177 ash concrete mixtuxes for underqround conduit mnstruction: Inst. e1ec.- electronic enginzcrs, Trans. Pcrfex: App. Systems, voLl 84, no- 9 , p?. 780-786, discussion 786-788. 1965.

* Yar~auchi, Shiro, et al, P/Lixing of fly ash c m t : Governwk Industrial &search Inst i tu te , Nagoya, Japan, Xagoya X q m Gijutsh Shikensho Hokoku, vol. 14, no. 4 , p?. 152-8, 1965. (in Japanese),