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Mr. Dymond — But it is done by the color.
You know some people are color blind and
their perception is not keen. You see I am a
little old-fashioned, or rather may believe in
old-fashioned su^ar manufacture.

Professor Blouin — The color here is so dis-
tinct that almost the blind could see it. Ilere
I have a little lime paste — here is some lime
water on the surface; that color can be very
readily brought back with lime water alone.

Captain Pharr- Let me ask you a question
there to see if I exactly understand your prop-
osition. You add the alkali there until you
give it the color. Then you add the acid to
restore it to the color of cane juice.

Professor Blouin — We do that in case we run
in an excess of alkali. If we did not know
the point where the acid was neutralized.

Captain Pharr— Then you add the other in-
gredients to bring it back to the point? '

Professor Blouin — Yes, sir.

Captain Pharr — And from that you calculate
lust the amount of lime that is necessary to
bring it to the proper point? Is that your

Professor Blouin — Yes, sir.

Captain Pharr — I think I understand it that

Dr. Stubbs— In our sugar house we sulphur
and then measure the amount of that acid
added by process. Suppose we sulphur to 5
cc. We know exactly how much lime to add
to each clarifier. It is determined by that
process there.

Professor Blouin— By adding this amount of
lime you will see the change.

Captain Pharr— That is exactly the same
thing; I understand it.

The Chair— You stated something about
milk of lime. You don't say whether, by this
experiment, milk of lime had the same effect
upon this alkali matter that the alkali had in
this burette. Is that the same juice you used a
few moments ago?

Professor Blouin — Yes, sir; by applying an
excess of lime you get this color. If I run an
acid in there to neutralize this alkalinity, the
color will be destroyed.

Member— That process there is to take the
place of litmus paper?

Professor Blouin— Yes, sir; it is a more del-
icate test.

Captain Pharr— That process is to take the
place of guessing?

Professor Blouin — Yes, sir.

Captain Pharr— That is what I thought.

Mr. Dymond — Is it practically any better?

Professor Blouin — Bv this means you put in
the exact quantity of lime necessary. Fre-
quently the sulphuring has been carried to
7 per cent, instead of carrying to 5 per cent.,
and the same amount of lime is used in each
case. This detects in a moment how much
sulphur you add, and .the variation carried in
there is never more than, say, 13^ to 2>^.
Frequently we encounter this variation during
the day, and the same amount of lime is added
to each clarifier, and the result is we have the
juice over-acid or over-limed.

Professor Stubbs— This is a very simple
operation ; there is nothing new about it. It
is just the application of an old principle to
sugar manufacture. Every chemist in a sugar
house knows this; and as Mr. Dymond re-
marked here, this is a most excellent way of
letting your sugar maker know if there is too
much or too litfle lime; but the difference be-
tween over-liming and underliming requires
an expert eye to tell exactly.

Captain Pharr — Is Baum^ a correct measure
of lime?

Professor Stubbs— Yes, sir, for lime, if you
keep it well stirred.

Mr. Crozier — Some lime takes a great deal
more water.

Professor Stubbs— Not if it is pure lime,
Mr, Crozier. If you mix slacked lime (that is,
Ca O -f Hj O, one part of lime and one part
of water, or what we call hydrate of lime)
with water you will obtain what you call milk
of lime; then the Baume spindle comes in to
tell the strength of this mixture.

Mr. Churchill — I am glad the sugar experi-
ment station has taken up this matter of liming
and sulphuring cane juices by actual chemical
test in the sugar houses. It is of great import-
ance to know just how much sulphur we have
added or ought to add, and just how much
lime we should use to neutralize this sulphur.
By the method which Professor Blouin has
just described, we can do this to a nicety
without any particularly skilled labor in the
sugar house. While in Nebraska last summer,
at both Norfolk and Grand Island, I saw this
testing being done by the ordinary workmen of
the sugar houses. At each liming tank, the
workmen had a set of burettes and testing
glasses by which they gradually gauged the
amounJt of lime that was added, and then at
each c^f^^^^^^^S^ ^^^^ ^^^ workman there had

similar glasses and apparatus by which he
tested the amount of carbonic acid gas added.
This was the case for both the first liming and
the second liming, the first carbonatating and
the second carbonating. About five years ago,
if I rememl>er right, relatives of mine in Eng-
land, among other books, sent me a small
volume entiued *'Dr. Shier's Method of Accu-
rately Testing Cane Juice for Clarification."
In this book the exact method that Professor
Blouin has just spoken of is described as hav-
ing been practised in the English provinces at
that time — about 1875— when the book was
published. I will say further, that in my
travels throughout Louisiana, in the interest
of the Provident Chemical Works of St. Louis,
I have found two or three houses where this
method is in daily practical use. In one of
them they employ two boys on a watch. By
means of the burette, and a standard alkali so-
lution, they determine the exact amount of
lime that must be added. These boys know
absolutely nothing of what they are doing.
They find out how many cubic centimeters of
alkali it takes to neutralize a certain specified
amount of the cane juice, and then from tables
already prepared direct the clarifier attend-
ant to put in so many cups of lime. In this
manner every clarifiation of juice is brought to
the same identical acidity or alkalinity. The
sugars produced by this method are absolutely
uniform. They have no trouble in making
sugars to sample. By the old method all un-
certainties of *' gauging by the eye " are done
away with. There can be no" uncertainty
about it. If this method is uniformly adopted,
I hope to see our ** sugar makers '' done away
with. Gentlemen, it is surprising to me, the
ignorance of these men. I might mention here
that one of them last year told me that he
would prefer to use litmus paper to clariphos,
but, as a matter of fact, he said he did not
think much of either one. Another one told
me that when he got ready to use an acid to
clarify with, he would use alcohol; that of all
acids he thought this was the best. I have an
idea that he thought It was best internally ;
and this man was in absolute charge of a sugar
house belonging to a progressive firm.

Mr. Dymond— Since the introduction of the
Cambray process at Governor Warmoth's, and
the manufacture of white sugars thereby, and
the introduction of the Drost & Shultz process
at Evan Hall and Belle Alliance, both of which
make white granulated su^ar, where sulphur
is largely used, we are takmg a very keen in-
terest in sulphur; and we learn. there is a dis-
position in this State to use sulphur in large
quantities; and it is said the results are satisfac-
tory, or, in fact, are more than satisfactory. The
results are desirable, and those who are
adopting these methods are disposed to con-
tinue. J^ow, if that be the case, if we ought
to use these larger quantities of sulphur— if we
ought to use larger quantities than we have
been using, if we want to reach the maxi-
mum limit reached by plantations, we should
like to be told that in some forcible sort of
way so we will be able to do it. Mr. Deming
spoke about the practical impossibility ot get-
ting too large an amount of sulphur in the
cane juice, and we are told in one of these
papers that one gallon of cane iulce, I believe,
will take some thirty-five gallons of sulphur
dioxide gas.

I remember that Mr. Communy, the intro-
ducer hereof the Communy sulphur apparatus,
held that one gallon would take sixty gallons
of sulphurous acid; so it seems to have a won-
derful power. How far shall we go with that?
Shall we go much farther than in the past? Near-
ly every sugar planter goes by a process of dead
reckoning. From any established point he en-
deavors to do that which is a little better; he
strives to do better until he arrives at a decree
of excellence that bears a favorable comparison
with the work done by his neighbor. Progress
has resulted throughout the whole State,
which, without the use of a large quantity of
sulphur, would have been less apparent than

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[VoL XX, No. 25.

now. A distinguiehed gentleman ten years
ago was advising us not to use sulphur at all,
and now we have learned to bridle this in-
jurious agent; we hold him down and make
him very useful to us. We have learned to
use sulphur in moderate cjuanlities. With ref-
erence to the Oambray or the Drost & Schultze
process, these processes recommend them-
selves to us, and we are led to inquire now as
to what we shall do. Shall we all force the
fumes of sulphur through the juice by atmos-
pheric pressure? 1 believe, generally, that in
the beet sugar countries they use sulphur in
that way. We generally secure a current by a
vacuum at the other end of the line, whereas
the Germans force the sulphur with a current of
atmospheric air. Now, it would seem to me
wise to bring out these points in full and learn
the latest ideas on the subject; we shall make
in Louisiana a very centre of observation.
There are many who are now waiting for this
data, awaiting for the results of this discussion
this evening. They are anxious to know what
to do about sulphuring.

The Chairman— There is doubt about the
importance of this subject, and I think that it
would be only proper, in view of the number
of scientists present this evening, that they
should give their views ^n the subject. Among
the scieniists present 1 would call on Profes-
sor Wilkinson.

Professor Wilkinson — I would say that as a re-
sult of my experiments 1 found that the larger
the quantity of sulphur used the better the clari-
fication obtained. I have forced it underpressure
and 1 have continued its use until I would get as
perfect coagulation with the sulphur as with
lime and sulphur together. I have had asso-
ciated with me as a student Mr. H. E. Trea-
deaux, who is a practical sugar maker, and he
tells me his best success has always been to
sulphur if possible until he sees this coagula-
tion take place. In turn we have found similar
results through heavy sulphuring on a small
scale in our laboratory at Tulane. [ am of
the opinion that the effect obtained by re-
peated sulphuring at some of our sugar houses
could be largely reached by allowing the juice
thoroughly saturated with sulphur dioxide to
remain for a longer time before liming.

Professor Stubbs— I know, in bis remarks
just now. Mr. Dymond alluded to me. Now,
I have visited a large number of sugar houses,
and in many I found they worked exceedingly
acid juice — in many instances almost as acid
as the juice Is now made In sugar houses. I
condemned then the use of sulphur, on ac-
count of the large inversion caused, and I
have always advocated, and do to-day, the
working of all juices neutral. 1 suppose in the
last two or three years we have performed
over a thousand experiments; not, as Dr. Wil-
kinson says, in the laboratory alone, but in
sugar house work. Before proceeding let us
stop and inquire what sulphur docs for us. I
think I can explain what sulphur d«es for our
juice. It has three effects. First, it bleaches;
it bleaches by taking away the oxygen from
organic matter. Second, it unites with water,
and forms sulphurous acid, which, when
mingled with the juice, suspends the active ac-
tivities of the ferments. It is therefore an
antiseptic. Third, as Mr. Blouin brought out
to-night, it partially precipitates the albumin-
olds; it also has a slight effect on the gums.

These results are frequently obtained by the
4i5e of only one cc. of sulphur dioxide to ten cc.
of juice, and two to three cc. accomplishes all
the chemical changes which can be induced
by use of sulphur. But the etticacy of heavy
sulphuring can be found in the immense pre-
cipitate which Is formed by the large quantity
of lime added to neutralize the excess of acid.
This precipitate introduces a mechanical
effect, and in its subsidence carries a large
quantity of impurities suspended in the juice.
Similar results accrue from heavy carbonata-

Experiments conducted with the uucroscope,
with graduated lines, capable of counting

approximately the number of particles of sedi-
ment in a drop of juice, have shown that after
a moderate use of sulphur and lime, sufficient
to perform the necessary chemical changes,
that after clariiication, especially when white
sugar be desired, depends upon the removal of
the very minute particles of impurities (dirt,
etc.) which remain suspended in the juice.

These experiments have shown that several
flltratlons— long settling in specially designed
settling tanks, or a heavy precipitate of any
character, all aid in removing these suspended
impurities from the juice. Many of the so-
called improved processes of working juices
tlnd their largest efficacy in the numerous ni-
trations required rather than chemical action
on the juices. Settling tanks and filter presses
will frequently accomplish similar results.
Heavy precipitates by changing the suspended
impurities aid greatly in clarifying juices, and
to this quality may be assigned the largest
benefit from the use of excessive sulphur.
This excess of sulphur requires an excess of
lime to neutralize, and the precipitate pro-
duced is a costly one. Several inventions have
proposed preparations of sand, earth, etc.,
as substitutes. We have given you chemically
all the reactions that take place through the
use of sulphur and lime. The remainder of
benefits by using them in excess is a forma-
tion of a heavy precipitate which goes to the
bottom, carrying with It suspended matter.
There Is another way of illustrating this ; Mr.
Demlng remarked in his paper, that it was a
well-known fact that all our canes carried
with them a large quantity of our soil, espec-
ially In wet weather, and your microscope will
show ihat it is present in particles which are
intlnltely small. That stuff becomes sus-
pended, and It \s with great trouble that we
get It removed. As soon as we add this excessive
amount of sulphur, followed by an excessive
quantity of lime, a precipitate is formed which
will entangle many of these fine particles of
earth and remove them. Our soils contain a
large proportion of particles whose sizes vary
between. 005 to .0001 of a millimeter and are in-
visible when in suspension in the juice, unless
viewed through a good microscope. In con-
centration many of these particles fiocculate,
and by settling or filtering the syrup, may be

We have used extensively the microscope in
testing these questions and beg to say, in pass-
ing, that settling in proper settling tanks from
one to one and one-half hours has secured
cleaner juice than was secured by any of the
numerous filter processes, or by using any
amount of sulphur and lime. Sulphuring so
that juice will show 5 cc. of acidity to every
10 cc. of juice and neutralizing with lime has

given in practical sugar house work all the
enetits that could be secured by using double
or triple these quantities. In fact less quanti-
ties of these substances can be used with great
efficacy provided the juice is thoroughly
cleansed afterward either by settling or filtra-

If we can adopt a policy by which we can
get our juice to settle and not filter, because
we have demonstrated the difficulties of re-
moving the very small particles by filtration,
the results obtained would be more satisfac-

In a filter press we always find some very
small particles that pass through (he pores of
the cloth, but when we settle, thoroughly set-
tle, we elimmate them.

Mr. Churchill — I believe sulphur is a very
good thing in its place, and sulphur has cer-
tainly made great strides in the sugar industry,
though In one house where It was used ex-
tensively year before last it was not used at all
during the past year, and in another house
where it was used extensively last year it will
not be used this year; but there Is something
which Dr. Maxwell has proven by his work at
the experiment stations in Louisiana and
Hawaiian Islands that Is much superior to sul-
phur in any form. I refer to acid phosphate.

or clarlphos, as it is known in the trade. It
may appear a little alien to the subject to men-
tion the matter here, but inasmuch as the
question of clarification of juice has come up
I believe It Is entirely In place. Listen to these
comparative results obtained by Dr. Maxwell
In his work in Louisiana, which Is described
In the paper he read before the Louisiana
Sugar Planters^ Association some few yearf
ago. Experiment No. 1 : When using sulphur
and lime there was precipitated 2.6 grammes,
of which 1 per cent, was organic matter, the
balance, 1 6-10 per cent, was mineral
matter. Experiment No. 3: With lime
and clarlphos, the total precipitate was
5.2 grammes, of which 2.48 was organic mat-
ter and 2.72 was mineral matter. Now, gentle-
men, the main point of clarification is to re-
move the organic matter. Which of these
would you prefer? Sulphur, which removes
1 per cent., or acid phosphate, which removes
two and forty-eight hundredths? It is a well-
known fact that by removing all organic mat-
ter we obtain a greater yield of sugar, inas-
much^ as organic matter retards crystallization.
In summing up his work he says about as fol^
lows: Sulphur does not appear to improve the
purity of juice, which is due to the fact that
sulphur as generally used In Louisiana does
not remove anything, but as a matter of fact
forms soluble compounds which remain in the
juice, and accumulating in the after products
retard crystallization and increase the
yield of molasses—sulphur, as a general
thing, forming soluble salts. On the other
hand the use of clarlphos with lime,
according to all these experiments, yields
the best results. The improvement is
caused by the actual removal of a large
amount of organic matter, and also by the
clarifying agents mutually removing each
other in the juice as an insoluble phosphate of
lime. Another advantage that he points out
is that the precipitate In the form of a filter-
press cake, or sediment, by the amount of
phosphate it contains, is a very valuable fer-
tilizer. Another item that he brings out is
that the brightness of the juice is greatly lost
when brought back to neutrality, and thecolor
required when making white sugar can only
be maintained with a degree of acidity which
is liable to cause a great loss of sugar by in-
version. Clarlphos, or acid phosphate, on the
other hand, he points out, acts with great
benefit on the coloring matter, more thor-
oughly precipitating these l)odies than any
other Itnown acid, and causes less loss by in-

Professor Stubbs — In reference to what Mr.
Churchill has said, I would say that the most
perfect clarification, in fact the ideal clarifica-
tion, is produced by acid phospate— the only
disadvantage being in regard to the cost of the
stuff. We found, too, that in order to operate
it successfully it was best to use two sets
of clarifiers, one for liming and one for adding
the acid phosphates.

Mr. Churchill — 1 would say, gentlemen, that
undoubtedly the best way to use acid phos-
phate would be like Dr. Stubbs has just said—
by means of two sets of clarifiers, but I have
seen It used, and successfully used in dozens
of sugar houses in Louisiana, in the same
clarifier that the lime had been added in. The
method of using it is about as follows : The
juice was limed to the alkalinity that was de-
sired, and heated, and brushed of scums. The
acid phosphate was then added in quantities
found most suitable. Steam was turned on,
and the whole thing brought just to the point
of boiling — just enough to mix it thoroughly.
The clarifier was then brushed again and
allowed to settle. The settlement was very
rapid, and a much more brilliantly clarified
juice was obtained. Of course, as Dr. Stubbs
has just said, two sets of clarifiers are the best,
but, from a number of years' experience in the
matter, I do not consider it necessary.

The Chairman— It would seem, perhaps,
that the increased use of sulphur might also

Digitized by


June 18, 1898.]



depend on the various processes which have
been adopted. We have the Cambray process,
also another process— the Drost & Schultze—
with both of which white sugar is made. Now
the chair is under the impression that double
sulpharation is used in one of these processes.
The ch^r understands that Mr. Jesserun is
here this eveninjjj, who has charge of the
Magnolia plantation and is familiar with the
Cambray process. The chair would call on
him to tell the association what he knows
about the Cambray process.

Mr. Jesserun— The Cambray process, as
used on Governor Warmoth's plantation, is as
follows: Lime is brought into the juice in an
excess, then sulphur is introduced— this lime
being precipitated to a certain akalinity. Heat
Is turned on about 180 deg. Fahr., and the en-
tire contents of this clarifler is sent through a
mud press. The filtered juice coming from
the mud press is again treated with sulphur in
another tank, where the entire alkaliaity is
reduced and brought to a slight acidity. This
juice again passes through a gravity press,
and from there it goes to the . evaporators,
where it is concentrated into syrup. The syrup
from the evaporators, before going to the
syrup tanks, is again filtered.

The advantage of the Cambray process lies
in the large amount of lime and sulphur used,
for it is a known fact that sulphur and lime
both are the only clarifying agents used so far
with success in the manufacture of sugar. The
use of a large amount of sulphur has a triple
effect. It bleaches the juice, it clarifies the
juice to a certain extent and it breaks up the
ferments contained in the juice — hence, pre-
vents fermentation in the after products. The
action of sulphur is not as much beneficial to
the first products as it is to the after products.
It makes the first product, while boiling in the
vacuum pan, a short, nervous and energetic
boiling, giving a better class of sugar than so
far obtained with any other process, the after
products yielding more sugar and running
freer in the centrifugals, being of a better color
than any other after products. The advantage
of the Cambray process also lies in the triple
filtriition enabled. Formerly we could not
filter our syrups, but with this process syrup is
filtered at 30 deg. Baum^. We obtained 200
pounds of total sugars, the after products
yielding from our cars for seconds 955 |>ounds
and for thirds 755 pounds; a full charge in the
centrifugal being used.

Mr. Soniat — How low did you reduce your

Mr. Jesserun—Our molasses was reduced to
28 sucrose.

Mr. Dymond — I would ask Mr. Jesserun
whether the pounds obtained was due to better

Mr. Jesserun— If the better clarification would
not count it would be just as well for the sugar
planter to take a raw juice from the millor
battery and concentrate it immediately into
syrup, granulating it into the pan.

Mr. Dymond^Are you still using the pro-

Mr. Jesserun — We used it until the latter part
of the season. I am sorry to say that there
exists in some Louisiana sugar houses condi-
tions which ought not to exist— so-called sugar
makers and engineers, who impose on the pro-
prietor by giving their views about things of
which they have not the least idea, causing
him to make changes accordingly. We made
155 pounds of first sugar to the ton of cane at
the end of the season, which I attributed to the
bad clarification: bad boiling in the vacuum

Mr. Dymond— -What extraction did you get?

Mr. Jesserun — We got 'o8 per cent, of the
sucrose, being equal to about 88 per cent, ex-

Mr. Dymond — In Demerara some twenty
years ago they made a dark sugar for the
American market, and with a large crystal. I

Online LibraryStanley Holmes MooreMechanical engineering and machine shop practice → online text (page 140 of 148)