Vo l. 31. No. 261.
S e p t e m b e r 1945.
SOME ASPECTS OF STANDARDIZATION IN OIL MEASUREMENT.
B y H. Hy a m s (Fellow).
Chairman of St a n d a r d i z a t i o n Su b- Co m m i t t e e No. 1 — Me a s u r e m e n t a n d Sa m p l i n g.
It is pleasing to be able to rep o rt th a t close co-operation on- oil m easure
ment m atters has been established between th e A.S.T.M. Com m ittee on Gaging, and th e I n s titu te ’s Sub-Com m ittee No. 1, th e first-fruits of this being th e jo in t publication of tw o docum ents entitled respectively “ P rin ciples Governing Oil M easurem ent Procedure ” an d “ Tables for C onvert
ing Metric Tons in Vacuo to Long and Short Tons in A ir.” These are published in th e current issue of A.S.T.M. Com m ittee D2 R eport, and in the 6th edition of th e I n s titu te ’s “ S ta n d ard M ethods for Testing Petroleum and Its P ro d u cts.”
The standardization work of th e In s titu te of P etro leu m ’s S tan d ard iza
tion Sub-Com m ittee No. 1 has been divided into seven sections, each dealt w ith by a separate Panel. These Panels cover th e following subjects :
(1) T ank calibration.
(2) M easurem ent of oil depths.
(3) M easurem ent of oil tem peratures.
(4) M easurem ent of oil gravities.
(5) Sampling.
(6) Calculation of volumes an d weights.
(7) A pparatus for oil m easurem ent.
A fu rth er Panel has recently been formed, including m em bers nom inated by th e S tandardization of T ar P roducts Tests Committee, to deal w ith m easurem ent of blerrds of coal-tar and petroleum products.
In subm itting th eir d ra ft m ethods to th e Sub-Com m ittee for confirma
tion, th e Panels draw a tte n tio n to any points of doubt or difficulty, or on which there has been division of opinion.
In th is paper it is proposed to discuss a few of th e problem s which have been or still are occupying th e a tte n tio n of th e Panels.
(a) T a n k Calibration.
New types of storage tan k s continue to appear, and although various authorities have recom m ended m ethods of calibration, no comprehensive publication on th e subject is y e t available. Panel No. I is working on th e p rep aratio n of such a docum ent, b u t among other, difficulties th e following th o rn y questions confront them :—
(i) Is th e external strapping m ethod to be preferred to diam eter m ethod for vertical tanks, or should both approved, if th e y are geom etrically equivalent ?
B B
th e internal m ethods be
politec;
340 HYAMS : SOME ASPECTS OF
(ii) Should allowance be m ade for expansion of th e ta n k u n d er oil head, and, if so, how should fully or p a rtia lly su p p o rted buried or bricked-in ta n k s he tre a te d ?
(iii) To w h at e x te n t should w ater-filling be used in calibrating small ta n k s or p a rts of large ta n k s ?
(iv) Should b o th w ater-filling an d strapping m ethods be accepted as stan d ard s for th e p re p aratio n of tab les for horizontal tan k s, and how are these m ethods affected if these ta n k s are tilte d ?
(v) W h a t procedure should be used to calibrate ta n k s w ith floating roofs, ship an d barge, rail-car an d road-w agon, spherical and spheroidal ta n k s, an d other bulk containers ?
These are a few of th e questions which th e T an k C alibration P anel must answ er before th e ir w ork can be considered as com plete.
(b) M easurement o f Oil Depths.
P an el I I has m ade su b stan tial progress in standardizing m ethods for m easuring th e d ep th of oil in containers, a te n ta tiv e b u t com plete set of procedures for these m easurem ents having been published in th e February, 1945, issue of th is I n s titu te ’s Jo u rn a l. T he Sub-C om m ittee invites com
m en t an d criticism on these, so t h a t an I.P . S ta n d a rd M ethod m ay be put forw ard. There are difficult problem s here also, such as, for exam ple :—
(i) W h a t m ethods are to be used to determ ine th e q u a n tity and oil-content of emulsified sedim ents on ta n k b ottom s ?
(ii) W h a t are th e real m erits of th e h y d ro static gauge an d th e meter for m easuring oil qu an tities ?
(iii) W h a t are th e best m eans of gauging a pressure ta n k containing a highly volatile gasoline where no gauge glasses are available ? (c) Sam pling and Average T a n k Temperature.
P an el IV is preparing a sta n d a rd procedure for obtaining th e . average tem p eratu re of th e oil in storage vessels; th is is obviously im portant, since an error of 2° F . in th e average oil te m p eratu re leads, in th e case of th e lighter oils, to an error of over 0-1 per cent, in volum e calculations.
A ny proposal to circulate a ta n k ’s contents because th e gauger w ants an accurate average tem p eratu re is usually looked on w ith disfavour by the installation m anager, so th a t oil in storage is seldom uniform in tem pera
tu re th ro u g h o u t its depth. Careful a tte n tio n therefore m u st generally be given to th e num ber of samples draw n, an d th e levels from which they are tak en , as well as to th e ap p a ra tu s an d procedure used for drawing the sam ples a n d for tak in g th e ir tem peratures.
(d)' Apparatus.
Specifications for recom m ended ty p es of dip tap es, dip w eights, ullage rules and w ater finders have been p rep ared b y P an el V II an d appear in th e pap er by P anel I I on “ M easurem ent of Oil D epths ” referred to above.
Much com m ent on these is expected, because th e oil gauger undoubtedly has very strong likes an d dislikes where oil m easurem ent ap p a ra tu s is concerned.
STAN DARDIZA TION IN OIL M EASUREM ENT. 341 In te re s t has recently been aroused in th e m aterials to be used for m easuring w ater depths and ullage levels in storage tanks.
H ydrom eters and sam plers are now carefully specified in S tan d ard M ethods, an d it is hoped to produce before long recom m ended standards for therm om eters to be used in oil tem perature work.
(e) Standard Temperature in Oil Measurement.
I t is n o t out of place to recall here th a t a short tim e ago th e In stitu te aligned itself w ith th e A .P .I. an d th e A.S.T.M. by confirming its accept
ance of 60° F . as th e sta n d ard tem p eratu re b o th for specific gravities of petroleum oils an d for correction of oil volumes. This declaration of policy on stan d ard tem p eratu re in th e petroleum in d u stry was necessary because adherents of th e m etric system proposed to have 20° C. recognized as th e international sta n d ard te m p eratu re in th e petroleum industry.
(f) Units of Measurement and Tables.
This difference of view on sta n d ard tem p eratu re leads n atu rally to a discussion of th e system s of weights an d m easures which are widely em ployed, and th e necessity for inter-relating them for commercial usage;
the prospect of th e adoption of a n y in tern atio n al system of weights and measures would seem to be as rem ote as ever. In th e oil in d u stry th e three principal system s are th e American, th e Im perial or B ritish, an d th e Metric. B y its publication in 1932 of “ S tan d a rd W eights an d M easures,”
a booklet which laid down a u th o ritativ e conversion factors in th e three systems of m easurem ent, Sub-Com m ittee No. 1 m ade a valuable con
tribution tow ards stan d ard izatio n of conversion factors in oil m easurem ent calculations. T he tables in t h a t book have been accepted in th e U nited States, and in tern atio n al sta tu s m ay be claimed for them . B u t th a t is only a fraction of th e problem . So long as oil is handled b o th by volume a t stan d ard te m p eratu re and b y weight, we have to guide those concerned in th e sim plest an d m ost accurate m ethods of com puting quantities. A n im portant contribution in th is connection is to be th e publication by th e In stitu te of Petroleum in th e near fu tu re of a book of oil m easurem ent tables. The production of th is au th o ritativ e book of over 300 pages is perhaps th e biggest standardization ta sk which Sub-Com m ittee No. 1 has so far undertaken. I t provides a set of tables which will allow th e correct conversion of weights in vacuo in th e m etric system to weights in air in th e B ritish an d A m erican system s. The tables will be in very close align
m ent w ith th e A m erican B ureau of S tandards tables, so widely used in th e American oil industry, b u t as a B ritish S tandardizing body th e Sub- Com m ittee has n a tu ra lly constructed th e tables so th a t th e y will facilitate weight a n d volum e com putations in B ritish units. I t is realized, however, th a t th is new production does not complete th e w ork under this heading.
I n th e n o t very d ista n t fu tu re a wider variety of commercial products will be available, and it is n o t certain th a t th e present tables for correcting specific g rav ity an d volume for tem perature change will be satisfactorily applicable to these new products. I t is possible th a t th e changes necessary m ay involve reconsideration of th e whole basis on which th e present tables are com puted.
Again, tab les are needed w hich will allow red u ctio n to 60 F . of th e specific gravities an d volum es of th e liquefied gases— propane, b u tan e, an d th e like. These tab les should, o f course, be based on or correlated w ith some simple physical p ro p e rty of these products, one w hich can be m easured easily in a sm all in stallatio n . Tables for blends of petroleum p ro d u cts w ith coal-tar pro d u cts an d w ith alcohol m u st also be provided, b u t, as already m entioned, steps tow ards th is have been ta k e n . Prelim inary investigation shows t h a t th e problem s w hich th e new P a n e l will have to consider are n o t likely to be easily solved.
This pap er shows t h a t m uch has already been done on th e stan d ard iza
tio n of oil m easurem ent procedure, although th e Sub-C om m ittee’s Panels are likely to have heav y program m es of w ork for a considerable tim e yet.
V aluable co-operation has been received from all m em bers of th e Sub- C om m ittee in th e w ork on w hich we have been engaged and, since the bu lk of t h a t w ork has been carried o u t u n d er w ar-tim e conditions, the progress w hich has been rep o rted speaks fo r itself.
342 SOME A SPECTS OF STA N D A RD IZA TIO N IN O IL M E A SU R E M E N T .
343
SULPHUR ESTIMATION BY LAMP METHOD USING I.P. TEST 107/45 (T).
B y A. R . Ja v e s, B.Sc., F.R .I.C . (Associate Member).
In th e sixth edition (1945) of “ S tan d ard M ethods for Testing Petroleum and Its P roducts ” th e In s titu te of Petroleum has adopted, as a ten tativ e standard, an additional lam p m ethod for th e m easurem ent of th e sulphur content of petroleum products.
The previous lam p m ethod (I.P. 62/42) is lim ited in scope, n o t being suitable for sulphur contents of less th a n about 0-01 per cent. Also, the apparatus does n o t perm it of th e com bustion being carried out in purified air.
I t is now frequently necessary to measure sulphur contents much lower th a n 0-01 per cent, and to b urn th e te s t sample in an atm osphere sub
stantially free from im purities. In th e case of th e volum etric m ethod th e impurities include, not only sulphur compounds, b u t also acid vapours and m aterials which form acids when in contact w ith th e flame. The gravim etric and turbidim etric procedures, based on measuring a p re cipitate of barium sulphate, are affected only by sulphur-bearing im purities.
A blank te st is usually m ade for these im purities by burning a sulphur- free m aterial, such as alcohol, in another ap p aratu s an d subtracting the titratio n of th e blank from th e titra tio n obtained w ith th e te s t sample.
If the sulphur content o f th e te s t sam ple is low, th e n it is possible for it to be alm ost equalled by th e blank, in which case th e results obtained for the sulphur content of th e te s t sam ple are very unreliable.
There was, therefore, a need for a stan d a rd m ethod in which th e p ro cedure for w orking-up th e te s t solution could be' chosen to suit th e m ag
nitude of th e sulphur content of th e sample, using a form of ap p ara tu s suitable for carrying out th e com bustion in purified air.
The new lam p m ethod I.P . 107/45 (T) is designed to cover th e full range of sulphur contents which are likely to be m et, and is suitable for m aterials ranging from gases to gas oil. The a p p aratu s is suitable for burning th e sample in purified air, or in a m ixture of oxygen w ith nitrogen or carbon dioxide from cylinders.
W hile this procedure does n o t elim inate th e need for a blank test, in general it ensures th a t th e am ount of sulphur found in th e blank te st is n ot excessive. A large p a rt of th e blank can come from th e reagents.
The lam p is so designed th a t prim ary ah’ is injected into th e wick tu b e 30 mm. from th e top. This gives a very rapid ra te of combustion, and even highly arom atic m aterials can be burned w ithout smoking. I t is custom ary to use enough prim ary air to produce a steady and smoke-free flame, b u t not enough to produce a bunsen-burner effect. M aterials in th e gasoline range can often be burned a t a ra te as high as 8 m l./h r.; kerosines a t ab o u t 5 m l./hr. Gas oils will b u rn a t ju st over 1 m l./hr., if previously mixed w ith a sulphur-free diluent.
The lam p is constructed w ith th e burner and th e oil flask sealed together, so as to prevent th e loss of vapour which m ight occur if th e burner were corked in to th e oil flask. A T-piece burner is used for gases. The wick
344 JA V E S : SU LPH U R ESTIM A TIO N BY
is introduced through th e filling hole into th e oil flask an d th e n pulled in to place w ith a hook-ended piece of wire. *
The chim ney is large enough to provide a sufficient reserve of air to p rev en t th e flame from going out while th e lam p is being corked in.
The w ater jack et is fitted to th e o u tle t tu b e so as to cool th e flue gas passing to th e absorber. W ith o u t th e w ater jack et, th e h e a t from th e burner is sufficient to m elt th e ru b b er tu b in g jo in t betw een th e chim ney and th e absorber an d to evaporate th e solution in th e absorber. T he chimney is quite easy to w ash th ro u g h w ith distilled w ater a t th e end of a test.
The absorber is a m odification of th e absorber specified for use w ith th e previous I.P .T . G.4 m ethod, th e enlarged to p allowing for th e increase in volum e of liquid in th e absorber, due to th e condensation o f th e w ater form ed by th e com bustion of th e sam ple, an d also helping to p rev en t the absorber solution bubbling over in to th e Drechsel bottle. A drain tu b e is also provided so th a t th e absorber contents can easily be tran sferred to a beaker a t th e end of a te st, in pre p ara tio n for working th em up by the gravim etric or turbidim etric procedures.
The Drechsel b o ttle is used purely as a catch -p o t for a n y absorber solutions which m ay bubble over.
A flowmeter is used a t th e exit end of th e D rechsel to facilitate lighting an d control of th e lam ps, an d in addition it enables all th e lam ps and the blank to be ad ju sted to ta k e th e same q u a n tity of air. T he p u rity of the air is less critical if th is ad ju stm e n t is m ade.
This a p p aratu s has been in use for th e last th re e or four years for gravim etric and turbidim etric sulphur contents. Two operators can handle up to tw e n ty lam ps betw een them . W hen th e lam ps were first p u t into use it was noticed th a t operators preferred th e m to th e old style (such as those used for th e I.P . volum etric m ethod) on account of th e ease of operation.
The m ethod allows th e te s t solutions to be w orked u p volum etrically, gravim etrically or turbidim etrically. T he volum etric procedure is sub
stan tially th e same as th a t for m ethod I.P . 62/42, th e ad vantages of the new m ethod being an im proved control of th e flame, burning in purified air an d a m ore rap id com bustion of th e sam ple. I t suffers from th e same disadvantage as I.P . 62/42, in th a t n itric acid form ed in th e flame is recorded as sulphur, w ith th e result th a t it is n o t suitable for sulphur contents of less th a n 0-01 per cent.
The gravim etric and tu rb id im etric procedures do n o t suffer from this lim itation, as th e sulphur com pounds are m easured a fter precipitation as barium sulphate. The gravim etric procedure is quite conventional. I t is n o t suitable for sulphur contents of less th a n 0-001 per cent., b u t there is no upper lim it. T he rep eatab ility of results is of th e order of 0-001 per cent.
The tu rb id im etric procedure is suitable for sulphur contents down to 0-0001 per cent., w ith a rep eata b ility of 0-0002 per cent. There is an upper lim it for th e use of th is procedure, which depends u pon th e make of tu rb id im eter used a n d which is usually betw een 0-005 an d 0-01 per cent, sulphur, b u t th is range can be extended by burning less sam ple or by tak in g an aliquot p a rt of th e te s t solution. M easurem ent of the tu rb id ity produced b y th e barium sulphate is a very quick operation, and can be m ade w ithin a few m inutes of adding th e barium chloride. This
LAMP METHOD U SIN G I .P . TEST 107/45 (T ). 345 procedure is based on th a t given by Zahn 1 for th e m easurem ent of low sulphur contents in petroleum products.
The sulphur content range betw een 0 001 and 0-005 or 0-01 per cent, is covered by both th e gravim etric and turbidim etric m ethods, b u t the turbidim etric m ethod is th e more accurate of th e two in this region.
The efficiency of th e lam ps and apparatus, and of th e gravim etric and turbidim etric procedures, has been exam ined very thoroughly.2 The work included m easurem ents to ascertain w hether high boiling sulphur com pounds were likely to rem ain behind on th e wick of th e la m p s; w hether errors were likely to be caused by th e sulphur content of th e wick its e lf;
a comparison of blank tests- m ade w ithout a flame, w ith an alcohol flame and w ith an electric h e a te r; th e effect of sulphur in th e rubber-tubing jo in ts ; th e effect of te tra -e th y l lead on te s t results, etc.
The m ethod of te s t specifies th a t if th e gravim etric or turbidim etric procedures are going to be used to te s t a leaded fuel, th e n th e lead m ust first be rem oved by w ashing th e sam ple w ith fum ing hydrochloric acid.
The reason is th a t, if a leaded fuel is burned, p a rt of th e lead is deposited on th e wick and a larger p a rt on th e chimney. A portion of th e sulphur content of th e sam ple is deposited w ith this lead. This is n o t all dis
solved when th e chim ney is washed through w ith w ater into th e beaker of test solution a t th e end of th e com bustion. This effect is n o t peculiar to th e lam ps used w ith th is m ethod of test, though th e error introduced is larger th a n it would be w ith a lam p w ith a plain wick tu b e.
The order of m agnitude of th e effect of lead on th e results of a sulphur determ ination is shown by th e following values ta k en from a graph cor
relating th e results of ju st over a hundred te sts m ade on various classes of m otor fuel before an d after leading.
Su l p h u b Fo u n d, % . C o n ten t, % .
D elead ed . Slow L am p . F a s t L am p .
0-0001 0-0001 0-0005 * 0-0002 *
0-0010 0-0010 0-0008 0-0004
0-0040 0-0035 0-0026 0-0016
0-010 — 0-0076 0-0041
0-100 — 0-094 -—
* T he re aso n fo r th ese h ig h re s u lts is obscure. I t m a y be cau sed b y th e co -p re c ip ita tio n o f lea d w ith th e b a riu m s u lp h a te .
I t can be seen th a t quite serious errors can arise, p articu larly when th e sulphur content is low, if no precautions are ta k en to avoid errors caused by th e lead.
An alternative to deleading is being tried. This consists of washing th e lead film off th e chim ney w ith acid into th e beaker of te s t solution.
P r e lim i n a r y inform ation shows th a t it is very effective, b u t a final decision on th e procedure has n o t y et been m ade.
The blank te s t is always very im p o rtan t when testing m aterials w ith a low sulphur content, and it is useful to have some inform ation as to th e
1 Z ahn, V., I n d . E ng. Chem. (A n a l.), 1937, 9, 543.
2 J a v e s , A. R ., J . In st. P etrol., 1945, 31, 129.
contribution which various factors m ake to th e overall m ag n itu d e of th e blank. T he m ethod to be adopted for purifying th e air will depend largely on local circum stances. E xperience in a ru ra l d istrict has shown th a t scrubbing w ith a continuously renew ed supply of ta p w ater is as good as any other purifying tre a tm e n t. The p u rity of th e air*so o btained gives a blank te s t which is su b stan tially th e same as th a t o btained w hen working w ith a m ixture of oxygen w ith nitrogen from cylinders.
Provided th a t th e blank is n o t too large relative to th e sulphur content of th e fuel, its actu al m agnitude does n o t m atte r, as long as it is a constant q u a n tity for all th e lam ps. A recent analysis showed t h a t th e greater p a r t of th e blank came from th e reagents an d distilled w ater. The reagents were all used in m easured quantities, so th e ir c o n trib u tio n was fixed, and th e q u a n tity of distilled w ater used was k e p t as c o n sta n t as possible by to p p in g all th e beakers up to th e sam e level a fter w ashing out the ap p aratu s. A grad u atio n m a rk was p a in te d on th e beaker to facilitate 346 SU LPH U R ESTIM A TIO N B Y LAMP M ETHOD U SIN G I . P . TEST I U 7 /4 D ^T).
th is. The results of th e analysis w ere :—
B la n k D e te rm in a tio n . S u lp h u r
F o u n d , mg.
A v erag e o f 14 b la n k d e te rm in a tio n s u sin g th e e le c tric h e a te r in p lace
o f a flam e . . . . . . . . . . 0-170
B la n k d u e to d istille d w a te r a n d re a g e n ts . . . . . . 0-158
B la n k d u e to a ir b y difference . . . . . . . 0-012
The portion due to reagents an d distilled w ater was th e n exam ined for th e contribution which each m ade to th e blank, w ith th e following results :—■
R e a g e n t. Q u a n tity U sed in a N o rm a l S u lp h u r T e s t.
S u lp h u r F o u n d , m g .
D istille d w a te r s a y 400 m l. 0-039
S odium c a rb o n a te N /4 . 20 m l. n il
N a O H /B r N /4 10 m l. 0-053
H y d ro c h lo ric a c id N / l 19 m l. 0-013
P h e n o lp h th a le in 1 d ro p n il
C a u stic so d a , 20% . . . . . 1-4 m l. 0-030
A lco h o l/g ly cero l 20 m l. 0-001
B a riu m ch lo rid e c ry s ta ls 0-3 g. n il
T o ta l . . . . . — 0 1 3 6
This to ta l differs from th e value of 0-158 mg., w hen th e y were all bulked together, by only 0-022 mg., and th is difference can be accounted as being well w ithin th e experim ental error of th e procedure em ployed.
The fact th a t th e barium chloride was also te ste d m ay seem strange, b u t it m ust be rem em bered th a t it is in th e form of sm all crystals. A b atch of sieved crystals will last for a very long tim e, during w hich it might become contam inated w ith solid im purities {e.g., dust). These im purities m ight be insoluble an d recorded in th e tu rb id ity , or th e y m ight contain sulphate which w ould be converted to barium sulphate w hen th e barium chloride crystals w ent into solution during th e test.
347
STABILITY OF FUEL OIL.
B y W. E. J . Br o o m,* Ph.D ., B.Sc. (Fellow).
Chairm an of S tab ility of Fuel Oils Panel of S tandardization Sub- C om m ittee No. 4— Gas, Diesel and Fuel Oil.
Du r i n g th e p a st tw o years th e S tab ility of Fuel Oils Panel of th e In s titu te of P etroleum ’s S tandardization Sub-Com m ittee No. 4— Gas, Diesel and Fuel Oil has been studying th e sta b ility of fuel oil, and a brief account of th e work of th e Panel is given here.
Due to th e com plexity of th e problem it was considered th a t progress could best be m ade by sub-division of th e subject into th ree m ain heads :—
(1) S tab ility of fuel oil in storage,
(3) S tab ility of fuel oil in blending operations,
(3) S tab ility of fuel oil when h ea te d to th e te m p eratu re of use.
St a b i l i t y i n St o r a g e.
For th e purpose of investigation of th e storage stability of fuel oil it was decided to investigate th e Sedim ent by H o t F iltra tio n te s t. The prim ary
S E A T G R O U N D TO FI T I - I N . STANDARD G O O C H P O R C E L A I N F I L T E R P L A T E ---
B O T T O M O F O U T L E T E N D SHALL BE S MOOT H AN D L EVE L AND SHALL AC T AS SUPPORT OR
BASE O F F U N N E L
I N L E T S T E A M
O U T L E T C R U C I B L E
H O L D E R
TO S U C T I O N
P U M P
F I L T E R F L A S K
S E D IM E N T A T IO N B Y H O T F I L T R A T I O N T E S T .
Fig. 1. Fig. 2.
S T E A M -J A C K E T E D F I L T E R I N G F U N N E L . A S S E M B L E D A P P A R A T U S .
object of th e Panel was to ascertain if good reproducibility could be obtained using th e te s t in various laboratories and, secondly, if th e results could be correlated w ith th e behaviour of fuel oils under norm al storage conditions.
The m ethod of te s t consists of khe filtration of th e oil sam ple through an asbestos filtering m edium in a steam -jacketed funnel. A diagram of th e funnel is given in Fig. 1.
* E s s o E u r o p e a n L a b o r a t o r i e s .
348 BROOM : S TA B IL ITY OF F U E L O IL.
To carry o u t th e te s t, 20 gram s of th e oil are w eighed d irectly in to a weighed filter funnel and, w ith th e a p p a ra tu s assem bled as in F ig. 2, filtered u n d e r a pressure o f 10 in. m ercury. A t th e end of th e filtratio n th e accum ulated sedim ent on th e sides of th e funnel is w ashed dow n w ith a prescribed q u a n tity o f high-boiling n a p h th a of specified p roperties. A fter a final w ashing w ith A.S.T.M. p recip itatio n n a p h th a , th e funnel is dried ou t a t 105° C. a n d th e w eight of sedim ent determ ined.
The p a rtic u la r m erit claim ed for th e S edim ent b y H o t F iltra tio n te s t is t h a t it discloses an d m easures ty p es of suspended m a tte r w hich m ay eventually deposit, a n d w hich are norm ally dissolved by th e boiling benzol used in th e older m eth o d I .P .— 53/42(T)— Sedim ent in F uel Oil by E x tra c tio n .
E xperience in reg ard to th is te s t has n o t been en tirely satisfactory.
©O n •
©"ZCMO u -.
«SluO
LUcd o ( j
u Z ^ or,
Z “ S O o • w 7 O 1/1 CC f . Y~
LsJ iff t- m u. 2 o >
^ 0*2 0-4 0 6
° / o S E D I M E N T BY H O T F I L T R A T I O N B E F O R E S T O R A G E
Fig. 3.
C O R R E L A T IO N O F S E D IM E N T A T IO N W I T H S E D I M E N T B Y H O T F I L T R A T I O N .
W hile th e six co-operating laboratories o b tain ed good reproducibility for th e sedim ent present in certain of th e oils before storage, th e determ inations of sedim ent in th e to p 75 per cent, a n d th e b o tto m 25 p er cent, of samples stored a t 100° F . for 28 days were n o t so consistent. I n general, d eter
m inations on th e stored sam ples showed t h a t some increase in to ta l sedi
m e n t h a d occurred during th e storage period, b u t th ese increases were not large.
T he difference betw een th e sedim ent in th e to p 75 p er cent, a n d in the b o tto m 25 p er cent, is ta k e n as a n indication of sed im en tatio n during storage. A n a tte m p t to correlate th is w ith th e am o u n t of sedim ent before storage is shown in Fig. 3. I n th e case of oil No. 5, a cracked 500-second ty p e fuel oil cu t back w ith gas oil, th e p ro p o rtio n ately higher sedim entation d uring storage m ay be due to th e low viscosity an d specific g ra v ity of this oil. This view is su p p o rted by th e curve in Fig. 4. A sim ilar curve is
BROOM : STA B IL ITY OF F U E L OIL. 349 obtained when th e difference in sedim entation is p lo tted against th e logarithm of th e viscosity.
U nfortunately, th e w ork has been ham pered by filtration difficulties due to the inability to o btain th e correct ty p e of asbestos, and such altern ativ es as a No. 3 sintered glass funnel have n o t proved satisfactory. E x p eri
m ental difficulties in determ ining th e sedim ent in th e bottom 25 per cent, of th e stored sam ples have also been experienced.
5 P. GR. AT 1 5 °C .
Fig. 4.
R E L A T I O N B E T W E E N S E D IM E N T A T IO N A N D S P E C I F IC G R A V IT Y .
While, therefore, it is believed th a t th is te s t m ay be of considerable use, it is obvious t h a t fu rth e r work m ust be done before it can be p u t forw ard as a sta n d a rd m ethod or even as a te n ta tiv e stan d ard . I t is also very desirable t h a t some correlation w ith norm al storage conditions should be established.
St a b i l i t y o n Bl e n d i n g.
In regard to th e stab ility of fuel oil in blending operations it was decided to exam ine th e possibilities of th e Xylene E quivalent te st. This is based on th e Oliensis Spot te st, and is carried o u t by heating, on a boiling w ater - b ath , 2 gram s of th e fuel oil w ith 10 ml. of a tria l m ixture of xylene and Oliensis solvent. A fter heating for 8 m inutes w ith agitation a t th e end
350 BROOM : STA B ILITY OF F U E L O IL.
o f each m inute th e flask is rem oved from th e w a te r b a th an d allowed to cool. A drop o f th e m ix tu re of oil an d solvent is th e n rem oved from th e flask by m eans of a p ip e tte an d placed on a No. 50 W h a tm a n filter paper.
A fter 10 m inutes th e drop is exam ined and, if th e n uclear ring is still visible, th e procedure is rep eated using solvent m ixtures w ith progressively increas
ing xylene contents, in 5 per cent, increm ents, u n til th e stag e »is reached w hen th e nuclear ring ju s t disappears. T his procedure is illu stra te d in Fig. 5.
T he low est percentage o f xylene in th e solvent to give no nuclear ring is rep o rted as th e X ylene E q u iv alen t. T hus, for th e exam ple given in Fig. 5, th e X ylene E q u iv alen t is 41 /45, in dicating th a t, w ith a m ix tu re containing 40 per cent, of xylene, th e nuclear ring still exists, b u t t h a t w hen th e xylene co n ten t h a d been increased to 4-5 p er cent, th ere was no ring.
A fairly satisfacto ry degree of correlation was found betw een co-operating laboratories, m ost of th e oils exam ined showing a reproducibility of ± 1 0 u n its. I n some cases, however, th is lim it was appreciably exceeded, and in one p a rtic u la r in stan ce resu lts v aried from 0 to 100 + .
T he m ethod does n o t a p p ear to be u n d u ly sensitive to th e composition of xylene or Oliensis solvent used, w ith in th e specification lim its, nor to th e te m p e ra tu re to w hich th e oil-solvent m ix tu re is cooled.
F u rth e r w ork will be necessary to define th e in te rp re ta tio n of th e results.
I t is probable t h a t a X ylene E q u iv alen t of 0 in d icates t h a t th e fuel oil is com patible w ith a paraffinous gas oil, w hilst a value of 100 pro b ab ly indi
cates incom patibility. More inform ation is needed on th e in terp retatio n of th e in term ed iate figures.
One criticism of th e te s t is t h a t th e procedure ignores th e possible peptis- ing influence which one oil m ay ex ert on o th e r oils in a blend. T he argu
m e n t has been advanced t h a t blending sta b ility cannot be dissociated from th e p a rtic u la r co n stitu en ts w hich it is required to blend. In o th er words, th e in sta b ility of a blend should n o t be considered peculiar to any con
stitu e n t, b u t as a p ro p erty of th e com bination of oils in th e blend.
The problem certainly seems to be one of colloidal ch em istry which cannot be dissociated from th e physical conditions w hich exist. A method which involves th e use of a lig h t solvent in assessing th e occurrence of sedim ent is, therefore, n o t viewed w ith en tire satisfaction.
St a b i l i t y t o He a t Tr e a t m e n t.
T he sta b ility of oils to h e a t tre a tm e n t has been exam ined using the N .B .T .L . or U.S. N av y H e a te r te s t. T his te s t, w hich was developed in the U.S. N av al Boiler an d T urbine L ab o rato ry , Philadelphia, an d is incorporated in th e U.S. N av y Specification No. 7-0-1 f. is s ta te d to have given good results in correlating th e behaviour of U .S. N av y fuel oils w ith deposits in pre-heaters u n d er conditions applicable to U .S. N avy steam p la n t practice.
The te s t is regarded highly b y th e U .S. N avy, b u t as y e t th e re is no evidence available to th e P an el to in d icate t h a t th e R oyal N av y or the B ritish M ercantile Marine have found it necessary to ap p ly such a te s t to th e ir fuel oil. This m ay be due to th e p a rtic u la r steam -raising technique used b y th e U.S. N av y or to th e w ider v a rie ty of fuel-oil ty p e s employed by it for steam raising.
4 0 % X Y L E N E 4 5 % X Y L E N E
Fig. 5.
N U C L E A R R I N G T E S T X Y L E N E E Q U I V A L E N T 41/45.
[To face p. 350.
- jr FU E L OIL S TA B ILITY C L A S S IF IC A T IO N CHART
ST A B L E FUEL OIL
NO. 1 B
B O R D E R L IN E QUALITY
B A
UNSTABLE QUALITY
B A
Fig. 8.
The a p p a ra tu s used is shown diagram m atically in Fig. 6 and a sectional view oi th e h e a te r elem ent is given in Fig. 7.
BROOM : STA B ILITY OF F U E L O IL. 3 5 1
j^ jS u L fi- r a e 7 /-/e e .^ fo c o
/ - y t e c y ' G /.& S S / u a s S r s s c 7og£-
IV //ZS i7 .,e /v £ !A 'r
cvv iPo/ej^£?&
Fig. 7.
Briefly th e te s t consists of subjecting th e oil to a heating te s t which lasts.
20 hours, during which tim e th e oil is h eated to a tem p eratu re of 200° F . The oil is pum ped over th e outside of a steel tube, inside which is an electric h eater elem ent m aintaining a tem p eratu re of 600° F . The results of th e
352 BROOM : STA B IL ITY OF F U E L O IL.
te s t is assessed on th e basis of th e appearance o f th e tu b e a t th e conclusion of th e 20 hours.
An 8-in. section of th e steel tu b e is w ashed b y flushing w ith a stream of benzol. A fter th e benzol has d rain ed off, one-half of th e w ashed section is hand-w iped w ith a clean soft cloth. T hus, th re e sections of th e tu b e are available for ex am ination :
(a) a w iped, w ashed s e c tio n ;
(b) an unw iped, w ashed sec tio n ; an d (c) a n unw ashed section.
D ependent on th e appearance of th e se sections, th e oil is ra te d as
“ S ta b le ,” “ B orderline ” or “ U n sta b le .” T he m eth o d of ra tin g is indi
cated in Fig. 8. O riginally th e U .S. specification differen tiated 5 types of oils, b u t a p p a re n tly w ider experience w ith th e te s t has resulted in sim plification.
W hen th e P an el com m enced th is w ork it was a n tic ip a te d t h a t th e re might be some difficulties in ob tain in g rep ro d u cib ility o f resu lts betw een labora
tories, on account of th e q u a lita tiv e m an n er in w hich th e assessm ent was m ade. I n practice, however, th is d o u b t was n o t realised, as shown in the following ta b le :
N .B .T .L . He a t e r Te s t.
Oil.
L a b o ra to ry .
1 2 3
1 S ta b le S ta b le _
2 B o rd erlin e B o rd erlin e —
3 U n s ta b le U n s ta b le —
4 ‘ — S ta b le S ta b le
5 — B o rd e rlin e B o rd erlin e
6 S ta b le S ta b le S ta b le
7 S ta b le S ta b le S ta b le
8 B o rd e rlin e — S ta b le
T hus, for th e eight oils exam ined th e re was only one case of disagreement an d th is only as to w hether th e oil was “ borderline ” or “ sta b le .”
F rom th is p o in t of view, therefore, th e te s t m ay be regarded as satis
facto ry although th e P an el has no evidence as to how th e resu lts check with U.S. N avy practice. Sim ilarly, th e P anel has no evidence to indicate that its general adoption as a te s t for all ty p e s of m arine fuel is necessary. Up to th e pre se n t th e w ork has bepn confined to oils w hich conform to the U.S. N avy Specification 7-0-1 f. viscosity clause, i.e., oils having a viscosity below 225 secs. S.U. a t 122° F.
F rom th is b rief account of w h at has so far been accom plished by the P anel, it will be seen t h a t th e re still rem ains m uch to be achieved before sa tisfacto ry te s t m ethods are produced w hich will in d icate th e stability characteristics of fuel oils in relatio n to p a rtic u la r conditions of use. I t is also obvious t h a t th ere is still relativ ely little knowledge concerning the m echanism w hereby th o se changes occur in a fuel oil w hich cause it to be designated as “ u n sta b le .”
353
THE PROBLEM OF DEVISING TESTS FOR SOIL STABILIZATION.
B y L. G . Ga b r i e l, B . Sc. (Fellow).
Chairm an of S o i l S t a b i l i z a t i o n P a n e l o e S t a n d a r d i z a t i o n S u b - C o m m i t t e e No. 7— A s p h a l t i c B i t u m e n .
It would probably be correct to call th e In s titu te of P etroleum ’s decision to appoint a Soil Stabilization Panel an exploratory one. The first m eet
ings of th e Panel early in 1943 soon indicated th a t th e problem s on which attention was to be focused were som ew hat different from those norm ally encountered by such bodies.
The difficulty lay in th e som ew hat restricted range of practical experience available. E xtensive lab o rato ry studies h ad been m ade both a t th e R oad Research L aboratory a t H arm ondsw orth and in several of th e commercial laboratories represented on th e Panel, and to a certain e x te n t th e con
clusions of these investigations h ad been checked in th e field, b u t th e influence of a wide v ariety of practical conditions rem ained unexplored.
Acknowledgment m ust be m ade of th e great value of th e American speci
fications d rafted by th e A.S.T.M. and th e A m erican Association of S tate Highway Officials, b u t it was felt th a t m any of these te sts needed close scrutiny before being included as th e y stood in any B ritish standards which m ight be set up.
I t should be em phasized a t th is point th a t th e P anel was unanim ous in its desire not unnecessarily to m ultiply th e num ber of tests which would apply to a n y particu lar p ro p erty or; aspect of th e problem . Thus, th e procedure adopted was to collect as m any as possible of th e sets of tests already published in different countries, and th e n to determ ine th e origin of any differences which m ight exist, and to endeavour to arrive a t a logical m ethod of operation which m ight stan d a good- chance of ultim ately being acceptable to all parties. In some cases th e u ltim ate choice of test conditions m ight coincide w ith one of th e already published m e th o d s; in other cases an effort was m ade to deal w ith complications or factors which had a p p aren tly n o t been ta k e n into account by existing m ethods.
As an illustration of th is th e question of th e level of com paction a t which perform ance te sts of various types should be u n dertaken should be cited. There is an Am erican com paction procedure which has received a m easure of recognition as a stan d ard procedure, and which is generally known as th e P ro cter Method. In this m ethod th e soil m ix is filled into a m ould having a diam eter of 4 in., and is th e n tam p ed w ith a ram m er having a diam eter of 2 in., tw enty-five blows of th e ram m er being given, each one w ith a free fall of 12 in. A n effort is m ade to distribute th e blows evenly over th e surface of th e specimen. The problem is w hether th e degree of com paction reached in this m ethod of working bears any relation to th e actu al values achieved in th e course of field operations.
Obviously, such criteria of excellence of th e finished work as w ater-
354 G A B R IEL : TH E PR O B LEM OF
resistance, bearing capacity, an d so on, will depend en tirely on th e degree of consolidation of th e m aterial, an d it is a m a tte r of g reat im portance th a t d a ta should he available showing some co n stan t relatio n betw een the results of th e te s t an d th e perform ance of a c tu al m ateria l on th e site.
This is w here th e difficulty lies.
A m erican experience w ould seem to show th a t th e P ro cter sta n d ard of com paction is a fair an d reasonable one to aim a t w ith ordinarily available p la n t as used for such work. T he w ork of th e R o ad R esearch L aboratory in E ngland ten d s tow ards th e same conclusion. N evertheless, it is known t h a t a ra th e r higher degree of com paction, if obtainable in practice with reasonable care an d a tte n tio n , would be conducive to a higher stan d ard of perform ance, an d in some cases would allow of th e use of m ore economical aggregates. More recently higher stan d ard s of com paction have appeared ra th e r te n ta tiv e ly in th e U.S.A. and th ere is a feeling on th e p a r t of some m em bers of th e P an el t h a t we should n o t h u rry to accept th e Procter level of com paction in E n g lan d u n til th e tre n d of a c tu a l field-work is seen m ore clearly.
There is a fu rth er problem associated w ith th is question of th e standard level of com paction. As an obvious alte rn a tiv e to th e im p act m ethod of consolidation th ere is th e use of a steadily applied pressure. This is used in T est A .4 of th e schedule recently issued b y th e P anel. A t th e pressure level selected for th is test, i.e., 3500 lb./sq. in., th ere is no question th a t a ra th e r higher density is produced th a n b y th e P ro cter m ethod. I t is recognized t h a t th is is a ra th e r u n satisfacto ry position, b u t it should be possible to resolve it sim ply enough once a greater volum e of practical experience is available. T he endeavour should obviously be to select the highest level of com paction w hich can be achieved regularly in practice, w ith reasonable care in working, an d to determ ine as precisely as possible equivalent conditions for producing th is degree of com paction by impact or by stead y pressure.
O ther problem s which need a sim ilar increase in th e am o u n t of available p ractical experience for th e ir solution are th e devising of a sta n d a rd test for resistance to th e effects of frost, an d th e finding of a reasonably accurate chem ical m ethod o f analysis to determ ine th e binder c o n ten t of mixes stabilized w ith bitum inous m aterials.
The problem of th e effects of frost is a p a rtic u la rly difficult one. The R oad R esearch L ab o rato ry has been a t great pains to collect available d a ta regarding soil tem p eratu res during recent cold spells, an d efforts have been m ade to decide on th e order of te m p eratu re g radients w hich m ay be expected in severe w inter conditions in E ngland. B ased on these data th e P anel has endeavoured to form conclusions on th e probability of frost-heave in stabilized work. G enerally speaking th e bulk of experience is t h a t genuine frost-heave is of rare occurrence, b u t t h a t disintegration of surface layers due to th e effects of fro st is m uch m ore frequent. An effort is now being m ade to produce various te m p eratu re gradients in lab o rato ry specimens, a n d to stu d y th e ir effects on stabilized mixes. The w ork in itself is difficult, a n d adeq u ate correlation w ith behaviour in the field is essential, th e la tte r being p articu larly difficult in view of the norm ally tem p e rate clim ate in E ngland.
The problem s associated w ith th e accurate d eterm in atio n o f binder
D E V IS IN G TESTS FO R SOIL STABILIZATION . 355 contents are of quite another order. I t need n o t be em phasized th a t th e w ork of th e P anel is confined to soil stabilized w ith bitum inous m aterials, and it is only th is ty p e of binder for which it is being a ttem p ted to legislate.
The m ethods com m only practised w ith other bitum inous-coated road aggregates are those which obviously come first into consideration. I t is found, however, th a t th e high specific surfaces of norm al stabilized aggre
gates, coupled w ith th e usually ra th e r high a ctiv ity of these surfaces, results in th e strong reten tio n by absorption of considerable am ounts of the binder, which in consequence are difficult to recover in th e norm al way by solvent extraction. H ere experim entation w ith different com binations of solvents, allied possibly to procedures aim ed a t flocculating th e finer aggregate, are being studied, and it is regarded as probable th a t th e m ost serious of these difficulties will be overcome in th e fairly near future.
In w hat has been said an a tte m p t has been m ade to show some of th e problems which h a d to be faced prior to th e recent issue of th e P a n e l’s first report. Subsequent to th e appearance of th is rep o rt th e difficulties have become even m ore significant. The reason for th is is n o t far to seek : th e first rep o rt represents th e answers to questions on which th e agreed d a ta a d m itted of p ro m p t finality. I t was realized th a t th e really difficult problem s rem ained for subsequent tre a tm e n t, an d consequently the second rep o rt m ay still be some little while in appearing. N everthe
less, th e w ork goes on, and in th is connection it would perhaps be as well to rem ark in conclusion th a t th e B .S.I. Soil Stabilization Com m ittee R D /9 is now in th e field, although, owing to th e com plexity of th e p rep arato ry work, its agenda is still in process of being form ulated. The au th o r has been honoured b y being elected C hairm an of th a t Committee, an d was especially pleased to accept th e office, as it afforded th e prospect of very complete co-operation w ith th e I n s titu te ’s Panel. I t is hoped th a t th e pioneer w ork of th e la tte r body will lighten th e labours of th e larger Committee, a n d th a t th e I n s titu te m ay th ereb y strengthen its role as one of th e m ajor technological organizations of th e country.
c c
356
THE USE OF LIQUID-IN-GLASS THERMOMETERS
B y J . G. Du b h a m.*
In s p e c t i o n b e e o b e Us e.
It should be an invariable rule th a t before a n y th erm o m eter is used it should be inspected visually w ith th e aid of a sm all pocket lens and ex am in atio n m ade—
(i) of th e safety-cham ber a t th e to p of th e stem , to ascertain whether an y detached m ercury has collected therein, eith er as a film or in small glo b u les; and
(ii) of th e bulb an d co n tractio n cham ber, to ensure th a t there are no specks of gas in th e m ercury an d no detached m ercury in the contraction cham ber or along th e bore.
Ad j u s t m e n t.
T herm om eters frequently arrive from th e m an u factu rer w ith defects such as those already m entioned, a n d these can usu ally be readily adjusted.
F o r exam ple, th e “ I.P . 22W A.M. O xidation ” th erm o m eter often has detached m ercury held up a t th e to p of th e contraction cham ber and for a short distance along th e bore. Shaking will seldom p u t th is right, and it is alm ost always necessary to cool th e bulb u n til th e detach ed mercury comes down into th e contraction cham ber in th e form of a th in film. If th e side of th e stem is th e n ta p p e d gently, th e detached m ercury will form in to a globule clinging to th e wall of th e contraction cham ber. The ther
m om eter should th e n be k e p t free from v ib ratio n a n d th e bulb warmed w ith a m eth y lated -sp irit flame u n til th e m ercury is joined to th e main column.
W here gas is found en trap p ed in th e m ercury a t th e shoulder of the bulb, it will usually be cleared by cooling th e bulb b y im m ersion in solid C 0 2 or some suitable m edium u n til th e m ercury is cooled below th e speck.
In extrem e cases it m ay be necessary to cool th e m ercury to below its freezing p o in t an d th e n to force th e speck above th e m ercury by giving th e th erm om eter a dow nw ard swing.
D etached m ercury m ay be located in th e safety-cham ber a t th e top of th e stem , an d can generally be driven dow n th e bore b y applying a m ethyl
ated-spirit flame across th e to p of th e therm om eter. Should it become necessary to w arm th e bulb in order to rejoin th e m ercury, th e therm o
m eter should n o t be used for some hours u n til it has recovered from the tem p o rary depression of zero.
Th e b m o m e t e r s i n Us e.
Assuming th a t th e therm om eters are in good order, th e m ercury-in-glass ty p es present little difficulty in use. Those of th e spirit-in-glass type
* C o m m unication fro m T h e N atio n a l P h y s ic a l L ab o ra to ry .
should he cooled very slowly, and w ith pentane as th e filling it m ay take a t least an hour to cool these satisfactorily to th e boiling point of oxygen ( 182-97° C.). To ensure th a t no spirit is left along th e walls of th e bore, all spirit therm om eters should be cooled as slowly as possible, a good practice w ith sta n d a rd instrum ents being to cool a t th e ra te of 1 /3° C. per minute.
St o r a g e o f Th e r m o m e t e r s.
Care in th e storage of therm om eters is as im p o rtan t as care in use.
Those which have a tem p eratu re range below 0° C. (say —40° C. to 10° C.) should, as far as possible, be stored vertically, bulb downwards, in a cool place. Spirit therm om eters m ust be stored aw ay from th e direct rays of the sun.
Therm om eters which have been h eated should be allowed to cool to air tem perature (20° C.) before being p u t away. T hey should n o t be exposed to sudden heating or cooling, particularly in th e region of th e contraction and safety-cham bers.
Re-m a r k i n g t h e Di v i s i o n s.
I f it is found during use th a t th e p a in t has come out of th e divisions of th e therm om eter scale, a tem porary filling can be effected by rubbing an ordinary lead pencil over th e divisions. This will suffice u n til th e instrum ent can be w ithdraw n from th e ap p aratu s, cleaned, and th e scale divisions re-blacked.
St a b i l i t y o f Ze r o.
U nder th is heading th e suggestions are lim ited to th e sta n d a rd therm o
m eters “ I.P . 29W ” to “ I.P . 32W ” used in th e determ ination of Viscosity (Kinematic) in Absolute U nits (I.P .— 71/45 (Tentative)).
To obtain th e high degree of accuracy required it is essential th a t frequent checks should be m ade on th e ice-points of these therm om eters. F o r this purpose it is necessary th a t th e p u rity of th e ice should be above question.
I n addition to checking th e ice points, it m ay be desirable also to check one tem p eratu re on th e m ain scale—say 70°, 100° or 210° F. In m aking this check it is im p o rta n t th a t th e stirring of th e comparison b a th used should be adequate to give th e accuracy demanded.
These therm om eters are so openly divided th a t in use th e y should be tre ate d sim ilarly to calorim eter and Beckm ann therm om eters. Prior to th e taking of readings th ey should be subjected to sufficient vibration or tapping to overcome any “ situation ” of th e m ercury column.
Pa r t i a l Im m e r s i o n Th e r m o m e t e r s.
On those occasions w hen th e defined immersion line is not th e tru e immersion, which m ay, in some cases, be ra th er indefinite, common sense should be used in correctly interpreting th e immersion.
In th e case of some standardized therm om eters th e em ergent stem tem peratures have been specified, b u t th e difference found in actual practice should be tak en into consideration when applying th e therm o
m eter correction.
DURHAM : TH E U SE OF LIQ U ID -IN -G L A SS THERM OM ETERS. 357
3 5 8
TH E INSTITUTE OF PETROLEUM.
A Me e t i n g of th e In s titu te of P etroleum was held a t M anson House, 26 P o rtla n d Place, L ondon, W . 1, on W ednesday, M arch 14th, 1945, Professor F. H . Ga r n e r, P resident, being in th e Chair.
The Pr e s i d e n t said th a t th e p resen t m eeting was a special sta n d a rd ization m eeting, th e papers to be read covering some of th e m ain subjects w hich th e S tan d ard izatio n C om m ittee were a t present discussing.
The following p ap er was th e n re ad b y th e a u th o r :
“ Some A spects of S tan d ard izatio n in Oil M easurem ent,” by H . Hyam s (Fellow). (See pp. 339-342.)
D IS C U S S IO N .
Mb. J . S. Ja c kso n sa id h e h a d b e en a sto n ish ed to fin d t h a t th e re w as no real law la id d o w n fo r a t a n k w ith a b o tto m w h ich m o v ed . S h o u ld n o t som e definite con
c lusion b e a rriv e d a t a s to w h e th e r th e y sh o u ld h a v e a w a te r b o tto m o r n o t ? Mb. Hyams re p lied t h a t th e y w ere n o t c o m p u lso ry h ere, th o u g h th e y m ig h t be so in o th e r co u n tries. I t w as n o t u n u su a l, p a rtic u la rly in th is c o u n tr y , for gasoline ta n k s to h a v e w a te r b o tto m s, to a v o id tro u b le in gau g in g , a n d i t h a d b een comm on p ra c tic e d u rin g th e w a r to h a v e larg e w a te r b o tto m s, to m in im ize e v a p o ra tio n losses.
So fa r a s h e w as aw are, th e re w ere no e x is tin g law s in sistin g on w a te r b o tto m s , and w h ilst in c e rta in c irc u m stan c es su ch w a te r b o tto m s w ere usefu l, th e re w ere other good reaso n s fo r re sistin g c o m p u lso ry w a te r b o tto m s.
Th e Pr e s id e n t a sk e d how f a r t h e b o tto m o f th e t a n k m o v ed .
M b. P . Ke r r (rep ly in g to th e la s t q u e stio n ) sa id t h a t th e id e a t h a t th e b o tto m of a ta n k w as m o v in g w as p u t fo rw a rd m o re o fte n th a n w as n ecessary . W h en errors in m e a su re m e n t o c cu rre d th e su g g estio n w as m a d e t h a t th e b o tto m w as moving.
T h a t th e y d id so m etim es m ove w as c e rta in , b u t he th o u g h t th e su g g estio n w as p u t fo rw a rd m o re o fte n th a n th e c irc u m s ta n c es w a rra n te d . T h e fo u n d a tio n s o f a tan k h a d to b e p a rtic u la rly b a d o r th e o rig in al s ta b ility m u s t h a v e failed in som e way b efore th e b o tto m co u ld m o v e to a n y g r e a t e x te n t. H e co u ld re m e m b e r a ta n k in S h an g h ai w here th e b o tto m m o v ed u p a n d dow n, b u t p ro o f t h a t th e b o tto m was m o v in g w as seldom o b ta in e d . T h e o b je c tio n to p u ttin g w a te r in w as t h a t unless th e ta n k w as fo r use fo r w a te r d isp lac em e n t sto ra g e i t w a ste d sp ace fo r oil and in creased th e c o st o f sto rag e. L ikew ise th e p resen ce o f w a te r in cre ased th e ra te of ru stin g .
Mr. A. R . Javes th e n read his pap er :
“ S ulphur E stim atio n b y L am p M ethod U sing I.P . T est 107/45 (T),” by A. R . Jav es, B.Sc., F .R .I.C . (See pp. 343-346.)
D IS C U S S IO N .
Th e Pr e s id e n t said t h a t it w as a h a p p y th o u g h t o f S ta n d a rd iz a tio n S ub -C o m m ittee N o. 3 to p re s e n t a p a p e r w h en a p p a r a tu s su ch a s h a d b een u sed fo r so m a n y y ears w as rep laced b y a n ew piece o f a p p a ra tu s . T h e degree o f a c c u ra c y w h ic h co u ld be o b ta in e d w ith th e p re s e n t piece o f a p p a r a tu s w ould p e rh a p s com e a s a su rp rise to som e m em bers.
