close

Вход

Забыли?

вход по аккаунту

?

The construction and operation of a pilot plant for inulin extraction

код для вставкиСкачать
THE CONSTRUCTION AND OPERATION OP A PILOT PLANT
POR INULIN EXTRACTION
A Thesis
Presented to
the Faculty of the Department of Chemistry
University of Southern California
In Partial Palfillment
of the Requirements for the Degree
Doctor of Philosophy
by
Kenton James Leeg
June 1940
UMI Number: DP21728
All rights reserved
INFORMATION TO ALL USERS
The quality of this reproduction is dependent upon the quality of the copy submitted.
In the unlikely event that the author did not send a complete manuscript
and there are missing pages, these will be noted. Also, if material had to be removed,
a note will indicate the deletion.
Dissertation Publishing
UMI DP21728
Published by ProQuest LLC (2014). Copyright in the Dissertation held by the Author.
Microform Edition © ProQuest LLC.
All rights reserved. This work is protected against
unauthorized copying under Title 17, United States Code
ProQuest
ProQuest LLC.
789 East Eisenhower Parkway
P.O. Box 1346
Ann Arbor, Ml 48106- 1346
T h is d is s e rta tio n , w r it t e n by
......... I ^ U T O ^
............
u n d e r the guidance o f h h L - F a c u lty C o m m itte e
on S tudies, a n d ap p ro ve d by a ll its m em bers, has
been presented to a n d accepted by the C o u n c il
on G ra d u a te S tu d y a n d Research, in p a r tia l f u l ­
fillm e n t o f re q u ire m e n ts fo r the degree o f
D O C T O R O F P H IL O S O P H Y
S'F"
/y V
-V
•/ f.. ;
- - - - - ............
D ean
S ecretary
40......
C o m m itte e on Studies
ACKHOWLEDGMEim
The author wishes to express his appreciation to
Dr. LeBoy 3, Weatherby, who first suggested this problem, and
to Dr. B* E. Vivian,
fheir kindly interest and timely criti­
cism in directing this problem were a source of encouragement.
fhanks are due Mrs. Dorris Bucher, Mr. Bill Coleman,
and Mr. John P. Hanna for their indispensable assistance in
construction and operation; to Mr. Paul Carnes, Mr. Michael
Lowry, and Mr. Bay Van Best for technical advice and assist­
ance; to the Messrs. Pfluger of the Bainbow Dahlia Gardens,
Mr. Armstrong of Gardena, and Mr. Andre Menou for supplying
tuberous roots of dahlias for the experiments.
TABLE OF COBTENTS
CHAP TEH
I*
II.
PAGE
INTRODUCTION.............................
1
Statement of the pr o b l e m..................
2
Discussion of the source • . . . ...........
2
REVIEW OP LITERATURE......................
6
Physical constants and chemical nature
of i n u l i n .............................
6
Purification of inulin . . . ..............
7
Value of I n u l i n ..........................
8
Previous attempts on semieommercial prepar­
ation of i n u l i n ................. . • • •
III.
PRELIMINARY WORK
10
........................
15
* ....................
13
Inulin by modified sugar beet method . . .
13
Test of method of analysis..............
14
Quantitative Benedict's
16
Methods of analysis
................
Brix spindle...........................
Methods of extraction and c o n t r o l ........
16
16
Tests to determine pH of the solution con­
taining roots with varying amounts of
added calcium carbonate or sodium bicar­
bonate ...............................
16
Wash boiler m e t h o d ......................
20
Small scale diffusion battery and results.
21
V
CHAPTER
PAGE
Experiment # 2 ....... .. .............
22
Experiment # 3 ...................
. .
24
Experiment # 4 ....................... *
25
Experiment # 5 ........................
26
Filtration methods andresults • • • . • •
29
Controlled pressure inulin filtration
Experiment..........................
29
Inulin filtration in small area filter
press. Experiment #2 . ...............
30
Filtration of hot, crude inulin solution
to remove filter cell and decolorizing
charcoal........... .. .............
Experiment # 3 ..........................
30
Experiment # 4 ..........................
31
Experiment #5
..........
31
....................
32
CONSTRUCTION OF PILOT P L A N T ..............
33
Materials of construction• • • • ..........
33
The c e l l .................................
36
Assembly.................................
47
Auxiliary a p p a r a t u s ...........
48
Experiment # 6 . . .
IV.
30
Cutter
Filter press
............................
46
.............
52
Air compressor.........................
52
vi
CHAPTER
PAGE
Steam generator
Drier
.........
53
. . . . . . . . . . . . .
54
Miscellaneous equipment..........
54
P a i n t ...............
V.
55
DIFFUSION STUDIES OH A PILOTPLANTSCALE
Experiment #1 . . . .
.........
.
57
. . . .
58
Experiment # 2 ......................
Experiment #3
60
.............
62
Experiment #4 and 5 • ♦ ............
65
Experiment # 6 ......................
65
Extraction curve of cells insystem . .
. .
68
Determination of hydrolysis ofcrude inulin
Experiment # 7 ......................
Explanation of l o s s ...............
VI.
70
71
. . .
SUMMARY AND CONCLUSIONS............
BIBLIOGRAPHY.................................
74
77
82
LIST OF TABLES
STABLE
I*
II*
PAGE
Aoid Hydrolysis of Boots • • * • • • • • •
Determination of pH of Boot Suspension
with Varying Amounts of Salts
III*
IV*
V*
VI*
VII*
VIII*
IX*
15
* * * * *
17
Determination of Inulin Recovery with
Varying Amounts of Salts • • • • • • • •
18
Degree of Extraction of Inulin • • • • • •
80
Data
84
Experiment #8 • • • • • • • • • *
Data -- Experiment #3 • • • • • • • • •
•
85
Data --- Experiment #4 * . • • • • * • • •
86
Data
87
Experiment #5 • * • • • • * * • •
Composite Results Obtained with Small
Scale Diffusion Battery
• • • • • • • •
88
X*
Filtrate Time vs* Pressure * • • • • • • •
31
XI*
Filtrate Time vs* Pressure * • * • • • • *
38
XII*
Composite Results of Filtration of Hot
Inulin Solutions * • • • • • • • • • • *
33
XIII*
Experiment #8 • • • • • • • • • • • • • *
63
XIV*
Experiment #3 • • • • • ................
64
XV*
Experiment #4
• • • • • • • • • • • • * •
66
XVI*
Experiment #5
• • • • • • • • • • • • • •
67
XVII*
XVIII.
Determination for Extraction Curve * * * *
69
Determination of Hydrolysis of Crude
Inulin • • • • • • * * • • • • • • • * •
71
viii
TABLE
XIX.
XX.
PAGE
Experiment #7
. . ..
........ . . . .
72
Composite Basalts of Experiments #3, 4,
5, 6, and 7
.........
74
LIST OF FIGUBES
FIGURE
PAGE
I*
Taboroas Boots of the D a h l i a .............
3
S.
Small Scale Diffusion B a t t e r y ...........
23
3.
Inner Cell (Upside d o w n ) .................
37
4.
Diagram of Cell (Side v i e w ) .............
39
5*
Diagram of Cell (End view) • •» ...........
40
6*
Diagram of Cell (Top v i e w ) ...............
41
7*
Diffusion Cell (Open).....................
43
8.
Diffusion Cell • • • .....................
44
9♦
Complete Diffusion Cell ShowingInsulation
Areas
• • ..............................
45
10*
Filter S a c k .......................... ..
46
11.
Pilot Plant Diffusion BatteryOpened * .• .
49
13.
Diagram Top View of DiffusionBattery . . .
50
13.
Cutting Machine and Pilot PlantDiffusion
Battery in Operation ....................
14.
Mahogany Disc
. * ...................
. .
51
61
15.
Extraction Curve
.......................
68a
16.
Flow S h e e t ...............................
81
CHAPTER I
INTRODUCTION
Inulin is a polysaccharide composed of many levulose
18
units; the exact number of which is as yet undetermined*
Until recently it has been a comparatively rare substance used
only in the laboratory, and even there to a rather limited
extent*
Research as to its preparation has been in progress
in several laboratories during the last few years*
At the
University of Southern California investigations in this field
23
have been in progress by Weatherby and co-workers since 1928*
The chief value of inulin is its use in the preparation
of the sugar, levulose*
The production of levulose on a com­
mercial scale has been the dream of many chemists.
Various
methods have been attempted to produce levulose from its five
important sources*
These are the Jerusalem artichoke(Helian-
thus tuberosus L * ). Chicory root(Ciohorium intybus L.). the
Dahlia(Dahlia variabilis(Willd.) Desf., Sugar Beet(Beta vul­
garis D*), and Sugar Cane(Saccharum officinarum L.).^
How­
ever, in most of these attempts, the purification has been
tried on levulose itself*
Difficulties with crystallization
have occurred in every oase*
Where the raw material was su­
crose these difficulties have been surmounted, but the cost
remains high*
It has been the contention of Weatherby, in
his researches, that a syrup of a high degree of purity would
crystallize readily, and that the logical method of obtaining
this syrup was to purify the inulin before hydrolysis*
Statement of the problem*
It has been the object of
this study to develop a method of obtaining relatively pure
Inulin, in large quantities, from dahlia tuberous roots and
to build a pilot plant to determine a commercially feasible
method of extraction*
Di so us si on of the souroe *
The dahlia is a genus of
herbaceous plants of the family Oompositae*
The genus con­
tains ten species indigenous to the high, sandy plains of
Mexico*
The species, Dahlia variabilis is the one from which
the majority of the forms, now common, have originated*
2
The
ordinary, natural height of the dahlia is about seven or eight
feet, but one of the dwarf species grows to only eighteen in­
ches*
As is the case with many other plants the dahlia will
do relatively well with a minimum supply of moisture, but the
plant does better as the water supply approaches the optimum*
numerous varieties of dahlias are now raised for flow­
ers, examples of which are: cactus dahlias, show dahlias, and
pompon dahlias*
They are propagated from seed and by divid­
ing the large, tuberous roots; in so doing, care must be taken
to leave an eye on each tuber*
The best and most general mode
Figure 1.
tuberous roots of the Dahlia.
JX&0B*
4
of propagation is by cuttings.
Some of the varieties, the
"Queen," produce large, succulent tuberous roots,
These are
most satisfactory for inulin extraction.
Dahlias succeed best in an open situation, and in rich,
deep loam, but there is scarcely any garden soil in which they
will not thrive if it is properly fertilized.
Dahlias, on a
large scale, succeed well in most climates, especially if the
17
rainfall is moderately heavy.
Investigations in this laboratory have shown the tuber­
ous roots of the dahlia to contain from 6*5% to 14% inulin by
weight.
At the time that sugar beets were first considered
as a source of sugar, they did not yield over 8% sugar,
The
sucrose content has now been increased by selective breeding
to from 16% to 22%.
It may be assumed that similar increases
may be obtained with dahlias.
It has been estimated that a yield of from 400 to 460
bushels of roots per acre, or from 9 to 10 tons per acre,
might be obtained, and that large varieties might yield 700
bushels per acre.
A clump of dahlia roots weighing 70 pounds
was raised by Father Sohroeder of Mission Santa Barbara.
Close planting, in commercial dahlia raising for inulin ex­
traction, might bring the yield considerably above that of
sugar beets which average about 11 short tons per acre.
This
5
holds without the added advantage of selective breeding which
would further increase the yield.
CHAP (EBB II
BE VIEW OP LlfEBAfUBE
Physical constants and chemical nature of inulin.
Inulin is a white powder resembling starch when pure.
odorless and tasteless.
It is
It has two crystalline forms; i.e.t
white, double refracting, sphero-^crystals and acicular crystale.
18
Pormerly it was thought to be made entirely of fruc­
tose units; the number of which was in dispute.
Becently, it
has been reported that a very pure inulin, on acid hydrolysis,
yields 3% glucose and this has been suggested as a means of
investigating the molecular weight.13
However, if the hydrol-
ysis is achieved by enzymes, the per cent of glucose formed
is less.
16
fhe molecular weight has been estimated by Haworth
and by Pringsheim.^’*^
!2he evidence tends to indicate that
there are probably between thirty and sixty units of fructose
8 16
per molecule. *
As in the case of starch and proteins,
this large molecular size leads to the formation of colloidal
suspensions.
Consequently, though the solubility of inulin
in water varies from 0.014$ at 0° C. and 0.23% at 30° C. to
38.3% at 98
it is necessary to have a solution of about
8% inulin to insure precipitation at 20° C. before fermenta­
tion becomes appreciable.
Inulin forms a colloidal suspension
in water and precipitates very slowly if not present in a high
concentration*
This is especially trae with impure solutions
in which there may be protective colloids.
As a standard of purity, it has been suggested that:
1) the inulin be white, 2) should give less than 0.1$ ash,
3) should not reduce Pehling's solution, and 4) should display
n 3
a specific rotation of approximately -38 .
Air-dried inulin contains about 10$ water, but this is
18
bound water and cannot be removed without decomposition*
Por a complete discussion of inulin and its physical and chem­
ical nature, see Pringsheim, "The Chemistry of the Saccharides”
page 296, and Thorpe, Chemical Dictionary, Vol. II, page 53,
18.22
1921. *
Purification of inulin.
The first attempt to purify
Inulin by any standard method was given by Kiliani in I860.
His method involved the precipitation of the inulin from sol­
ution by freezing after the removal of albuminous substances
with lead acetate.
Essentially, this same method has been fol­
lowed in most of the later investigations.
H. A. Spoehr has
suggested a new method of purification which would not, however, be satisfactory for commercial practice.
21
In his meth­
od the juice extracted from dahlias is stored for five days
at -20° €•, then thawed and filtered.
The inulin is redis­
solved in hot water and stored again at -8° C. for several
8
days.
The resultant product has an ash of 0.16J6 to 0 .2$> and
a specific rotation of -35.5° to -38.1°#
Other methods of purification involve precipitation
23
with alcohol
or allowing the inulin solution to stand for a
long period of time with a preservative added.
In neither
case could the method be applied commercially because of high
operating costs or large losses of inulin.
Purification of inulin has been developed to a high
degree at the University of Southern California.
Bartel pre-
pared inulin by successive recrystallizations from hot water.
3
He was interested in obtaining inulin of the highest degree
of purity#
I'or this purpose he found it necessary to wash
the very pure product with alcohol and finally with ether.
To obtain inulin with a very satisfactory degree of purity
without going through several recrystallizations, Brobst rec­
ommends purification by the addition of 1$ Norite and heating
with five parts boiling water for one half hour, adding 1%
diatomaceous filter aid and filtering hot, cooling, and allowg
ing the inulin to precipitate.
Pure inulin can be obtained
from a commercial stock by this method without a repeated recrystallizati on•*
Value of inulin. At the present time purified inulin
has very few uses.
The inulin of Jerusalem artichokes can be
9
assimilated fey the human body#
However, the mechanism fey
which it is hydrolyzed in the feody has not feeen definitely
determined#
It is apparently hydrolyzed fey feacteria in the
intestines, fey a combination of enzymes and hydrochloric acid
in the stomach, or fey both.
Some animals may possess inulase
enzymes#
It has feeen suggested fey A . Goudberg that inulin is
7
an excellent food for diabetic patients*
He has shown that
inulin is utilized over a long period of time in the feody#
Shis allows the feody to oxidize a relatively large portion of
the carbohydrate with a minimum of glycogen formation and a
small increase in blood sugar concentration#
Ho verification
of or addition to this work has feeen done; further investi­
gations are advisable#
A test has feeen made on the relative value of levulose
and glucose in the diets of normal, growing rats*
'Pwo groups
of rats from the same colony were fed the same basic diets
with the same calorific values.
One group received most of
its carbohydrate in the form of levulose while the other group
received an equal quantity of glucose#
ence in weight gained was observed#
Ho appreciable differ­
It was found in every
case but one that the livers of the levulose-fed rats were
considerably heavier than those of the glucose-fed rats.1
Work has feeen done on the utilization of levulose as
compared to that of glucose and other sugars fey depancreatized
10
dogs.
5
It has been found that a diet in which the carbohydrate
used is levulose is utilized to a marked degree as compared
to a similar diet but with glucose as the carbohydrate.
This
difference is pronounced at first but becomes successively
less each day until at the end of thirty days there is no
noticeable difference.
After a period of time, during which
levulose is not fed, the animals' ability to assimilate this
5
sugar again becomes appreciably greater.
The utilization of levulose, prepared from inulin, by
depancreatized animals is being investigated in this laboratory
20
by other workers.
Previous attempts on semicommercial preparation of in­
ulin.
In 1934 inulin was prepared on a large scale in this
19
laboratory by Bieger.
fhe method developed by him was model­
ed after that of the cane sugar industry.
Since inulin is
not soluble in cold water, the roots were placed in a pressure
cooker and heated to a pressure of about 15 pounds steam at
which point the pressure was suddenly released and the soft­
ened pulp was pressed in a hydraulic press.
The expressed
juice was collected and the pulp was saturated with water aid
put back through the process again.
It was held that the
superheating made the inulin soluble in the cell sap and the
sudden release of pressure ruptured the cell walls releasing
the inulin in solution.
The inulin solution thus obtained
11
was purified, cooled, and set aside to crystallize,
fhis
method was tested using steam pressures of 5, 10, 15, and 20
pounds.
Fifteen to 20 pounds gave the most complete removal
of inulin.
In these cases the extraction was in the neigh­
borhood of 97%.
Duplications of these experiments were obtained by
9
Bolzman in 1938.
He then modified the method by shredding
the roots, boiling the pulp in boilers, and removing the juice
by pressing.
Shis was followed by a second extraction with a
smaller amount of water.
Ho pressure cooking was used, but it
was necessary to shred the roots, and in order to maintain a
concentration of inulin favorable to precipitation it was
necessary to return much of the water extracted back into the
press again.
By this method he was able to obtain extractions
as high as 93%.
Inulin has been produced on a large scale from Jerusalem
artichokes at Iowa State College by McGlumphy, JSiohinger, Hixon,
15
and Buchanan.
However, in their method the inulin was not
purified, but the extracted juice was immediately hydrolyzed
to levulose which was precipitated and purified as calcium
levulate.
fhe calcium was removed by the addition of COg,
the syrup was concentrated, and the levulose crystallized.
Levulose has been prepared by similar methods at the United
States Bureau of Standards by Jackson, who obtained U.S. Pat-
IE
ent #2,007,971 in 1935 on a method for the purification and
crystallization of levulose*^
The method of obtaining the
levulose is not specified, but Jackson has prepared levulose
from many sources*
Most of his work has been on the prepar­
ation of levulose from Jerusalem artichokes, but experiments
have been conducted on the preparation of levulose from dahlia
roots and it has been suggested that a satisfactory product
might be obtained from beet sugar molasses and from the hydrol­
yzed juice of the Chicory root*
In obtaining levulose from
dahlia roots he suggested that inulin might first be precipi­
tated and filtered and the rest of the levulose, as levulose
and levulins, should be hydrolyzed and recovered as calcium
levulate*
He showed that the inulin could be obtained with
a satisfactory degree of purity by filtering the hot inulin
solution through kieselguhr.10
Ho indication was shown of
this having been done beyond laboratory scale.
CHAPTER III
PRELIMINARY WORK
I.
METHODS OP ANALYSIS
Inulin by modified sugar beet method*
This procedure
is designed to determine the total inulin plus levulose minus
glucose in the ratio of the specific rotations of levulose to
glucose; however, this is justified, due to the small per cent
of levulose and of glucose*
A sample of 18*8 grams of ground
roots was placed in a 250 ml* Erlenmeyer flask; a homogeneous
sample, including juice, was assumed to contain 13*8 ml. of
water since the roots averaged 76% water.
Eighty-five and
two tenths ml* of water and 1 ml* concentrated hydrochloric
acid were added to bring the total liquid volume to 100 ml*
The hydrogen ion concentration was lower than would be expected
due to buffers in the roots.
About one fourth gram filter­
cell and about one half gram decolorizing charcoal were added;
this was heated in a water bath with frequent shakings for fortyfive minutes, using an air reflux.
The first few milliliters
and the residue were filtered and discarded*
The filtrate was
polarised with a sacoharimeter using sodium light.
If a two
decimeter tube is used, the reading is directly in per cent*
Direct percentage readings are possible because the
saocharimeter is built to read directly in per cent when the
14
correct amount of sample is taken*
It is designed primarily
for calculations of sucrose solutions*
If £6*048 grams of
pure sucrose is dissolved in enough water to make 100 ml* of
solution, the sacoharimeter is designed to read 100% sugar if
the reading is made through a two decimeter tube*
If a sample
of solution weighing £6*048 grams is diluted to 100 ml* and
the reading is found to be 45%, then that sample contains 45%
14
suorose.
!Zhis is an arbitrary scale, but it is convenient
for plant operation.
Since levulose has a specific rotation of -9£° and su­
crose a specific rotation of +66*4°, it would take less lev­
ulose to read 100% than sucrose*
fhe levulose would, of course,
read to the left instead of to the right*
£6.048 x
466*4
-9£
equals 18*8 grams of levulose in enough water to make 100 ml*
would read 100% if read through a two decimeter tube*
fhen a
sample of levulose solution weighing 18*8 grams in enough
water to make 100 ml* will read directly in per cent levulose*
fest of method of analysis*
In order to determine
whether the acid concentration was high enough to insure com­
plete hydrolysis of the samples, six duplicate samples were
hydrolysed with varying amounts of acid.
Each sample was hy­
drolyzed for one hour in a boiling water bath,
fhe pH of the
solution was determined using a Beckman pH meter immediately
after mixing and again after hydrolysis.
Each sample contained
15
18.8 grams of roots with water and acid to give 100 ml, of
solution*
fhe acid concentration was calculated on the basis
of acid added*
Ihe pH was then determined because it was to
be expected that the plant salts would buffer the solutions*
fABLE I
ACID HYDBOLYSIS OF W O T S
Sample #
1' ' Acid '
* Cone. Mix.
' pH after
mixing
jfinuiin
pH after
* hydrolysis *
read
1
0*01 U
3.22
3.80
5.9#
2
0.01 H
3.39
3.74
5.8#
3
0*03 N
2.25
2.37
12.8#
4
0.03 H
2.25
2.37
13.0#
5
0.10 U
1.45
1.36
12.9#
6
0.10 JJ
1.40
1.35
13.4#
The rotations of the sugar solutions were read at be­
tween 18° and 19° C*
!Ehls chart indicates that hydrolysis is
oomplete in one hour with a pH of less than 2*25 or with a
calculated acid concentration of 0*05 N, but is not complete
with a pH of 3.74.
Since the rate of hydrolysis varies direct­
ly with the acid concentration, the samples are probably com­
pletely hydrolysed in less than thirty minutes*
determinations have been made to verify this*
Satisfactory
therefore,
forty minutes hydrolysis, under the conditions where the acid
16
concentration Is mixed to 0,10 U, is entirely adequate.
Quantitative Benedict1s.
glucose determinations.
This is the standard used in
Since levolose reduces only 94JJ as
much copper Benedict's per gram as glucose, this correction
must he used.
Brix spindle.
This instrument is essentially a hydro­
meter which is graduated in brix or total per cent solids.
It is one of the instruments of control used in a beet sugar
plant for rough, rapid calculation of the concentration of
solids in sugar solutions.
It was necessary, in the work on
inulin, to have some means of determining the concentration
of the liquors obtained during the preparation of inulin in
order that any variation in control might be made immediately.
It was not expected that the Brix reading would give an accu­
rate estimate of the inulin concentration, but was used for
rough control.
II.
METHODS OF EXTRACTION AND CONTROD
Tests to determine pH of the solution containing roots
with varying amounts of added calcium carbonate or sodium bi­
carbonate.
Since it has been shown that inulin decreases in
stability with the increase in hydrogen ion concentration,
it was desirable to know the pH resulting from adding differ­
ent amounts of neutralizing salts in order that a control of
17
pH could be maintained*
A pH between seven and eight was
assumed to be best; however, it might be possible that a
slightly higher pH would be more satisfactory*
In order to
verify the former the following determinations were made*
Nine 50-gram samples of ground roots were each diluted with
100 ml* water*
To the separate samples were added the follow­
ing amounts of calcium carbonate and sodium bicarbonate and
the pH checked in each case:
TABLE II
DET1BMINATI0N OF pH OF BOOT SUSPENSION
WITH VABYINGr AMOUNTS OF SAITS
amount of salt
1.
2•
3*
A.
5.
6.
7.
8.
9*
0*5 gm. CaCOglppted)
1*0 gm*
i»
2.0 gm*
«t
4*0 gm.
0*5 gm* HaHCOg
n
1.0 gm*
i
t
2*0 gm.
n
4*0 gm*
no salt added
pH oi solution after
boiling 2 hours
pH
pH
pH
PH
pH
pH
PH
pH
pH
7.03
7.72
7.38
7.42
8.61
8.56
8*57
8.78
6.88
In each case the inulin from the samples in which sodium bi­
carbonate was used contained much more coloring matter*
An
attempt was made to determine the relative amounts of levulose
to inulin in these determinations, but no satisfactory method
was found*
Accordingly, another set of determinations was
made in which the inulin was separated and weighed in each
case*
Again 50 grams of roots were dilated with 100 ml* of
water per sample; the previous pH investigations indicated
that lower amounts of salt were satisfactory*
TABLE III
DETERMINATION OF INULIH RECOVERY WITH
VARYIHGr AMOOTTS OE SALTS
grams of inulin obtained
from 10 ml* of extract
amount of salt
1.
s*
3*
4*
5.
6.
7.
8*
0*£55 gm*
0*340 gm*
0*360 gm*
0*355 gm*
0*350 gm.
0*£85 gm*
sample discarded*
0*330 gm*
0*25 gm* CaC0*(ppted)
0*50 gm*
w
1*00 gm*
w
£•00 gm*
"
0.25 gm* HaHCOg
0*50 gm*
"
1*00 gm*
*
no salt added
*Sample spilled*
In every case the filtered mother liquor had a light
tan color in each of the samples in which calcium carbonate
was used and in the blank; those in which sodium bicarbonate
was used were much darker*
The higher pH of the sodium bi­
carbonate solution apparently favors the extraction of the
coloring matter from the roots*
The weights obtained in the
chart were those of inulin precipitated from 10 ml* of the
liquid by the addition of 90 ml* of absolute alcohol, filter­
ing the inulin, drying, and weighing it*
In every case where
19
calcium carbonate was used the alcohol brought down about 10
ml* of flocculent, inulin precipitate; about 15 ml. were ob­
tained in sample #6, 7 ml. in sample #5, and about 2.5 ml. of
a granular precipitate in sample #6.
The granular precipitate
from the sodium bicarbonate solution was more easily filtered
than the flocculent precipitate from the calcium carbonate
solutions*
The inulin obtained from the sodium bicarbonate
solutions had a distinctly disagreeable flavor while the cal­
cium carbonate product was tasteless.
able sweetness.
Neither had any notice­
The sodium bicarbonate inulin would be harder
to decolorize than that obtained using calcium carbonate.
However, due to the ease of filtration of the sodium bicarbon­
ate inulin, it might be advisable to make added determinations
of the relative merits of these two neutralizers.
It has been assumed in some cases that the volume of
precipitate obtained under the conditions of alcohol precipi­
tation gives an approximate idea of the inulin content of the
solution.
It seemed desirable that this assumption should be
checked, and that results obtained in Table III should be put
on a quantitative basis.
J'or these reasons precipitates were
filtered, dried, and weighed.
A comparison of the results
obtained by the two methods showed that the volume of the pre­
cipitate does not necessarily vary as the concentration of
the inulin.
Apparently the precipitate is more voluminous
when the solution has a low pH than when it is higher*
There­
fore, it is advisable to weigh all precipitates in calculations
of this kind.
Wash boiler method*
This method was attempted to de­
termine whether it would be feasible to use a small number of
cells in a series with final extraction of inulin being ob­
tained by pressing the pulp.
were ground in a meat grinder.
About 30 to 40 pounds of roots
To half of the roots was add­
ed 8 pounds of water; this was boiled for forty-five minutes.
The liquid was then poured off and the pulp pressed.
The ex­
tract, as well as the extract from the pressed pulp, was pour­
ed upon the remaining roots.
This was cooked again for forty-
five minutes; the extract was again poured off and the pulp
pressed.
The resultant liquor was clarified with filter-cell
and charcoal.
The filter-cell and charcoal were removed by
filtration through a centrifuge which was lined with paper,
Filtration was poor, due to gumming of the filter paper.
Two
gallons of juice were recovered; the inulin and levulose con­
tent of which was 12,6$, as determined by the saccharimeter.
TABLE IV
DEGREE OF EXTRACTION OF INULIN
stage
1, first pressed pulp
8, second pressed pulp
3, original roots
% inulin content
tM
£1
fhe results of this experiment indicate that the method might
he possible if four or five cells were used, but the labor
costs of several pressings of the roots would be prohibitive.
However, for laboratory scale production of inulin where high
recovery is not essential, the method is simple and adequate.
Small scale diffusion battery and results,
fhe diffus­
ion battery is one of the older methods of extracting soluble
materials from solids.
When the problem is to remove a high
per cent of the soluble materials without obtaining a dilute
solution, it is one of the most obvious methods to be used.
It is used with notable success in the extraction of sucrose
from sugar beets,
fhese extractions have been carried out on
the counter-current principle, that is, the solvent is fed in
at one end and the raw material is fed in at the other.
Know­
ledge of these principles led to preliminary extractions of
this type by Black, Hieger, and Holzman at the University of
A TQ Q
Southern California. *
*
2Che largest battery built by these
men was that of Holzman which consisted of six cells of about
500 ml. each.
It was his suggestion that this work be carried
further.
A battery of eight cells was built using glass bottles
of £50 ml. each and connecting them with glass tubing. (Figure
£)
In each case the entering liquid came through a short
tube while the outgoing liquid entered a long tube at the bot-
zz
tom of the cell as in a trap*
tate rapid changing.
Extra cells were made to facili­
The whole battery was then immersed in
a boiling water bath which kept the contents of the cells be­
tween 90° and 100° C.
A trial extraction was attempted using
the eight cells with a preheater and pressare supplied by the
water main*
Difficulties were encountered with the solids
plugging up the tubes*
This would build up a back pressure
until the stoppers blew out*
In order to obtain results the
stoppers were all removed and the liquor poured from bottle
to bottle at regular intervals.
The data would be affected
little by this as the increment of difference of concentration
was still fairly large.
The liquor obtained was difficult to
filter and large quantities of filter-cell and high suction
had to be used to obtain a product,
The solution was decolor­
ized with charcoal and filtered while hot.
precipitated by adding alcohol to about 35$.
grams of good inulin were obtained.
The inulin was
Seventy-nine
She experiment was of no
significance quantitatively and was of value only in pointing
out the difficulties.
Experiment #8.
In this experiment eight bottles again
were used in series, with the inlet at the bottom and the out­
let at the top.
A pad of glass wool was tied over the opening
to keep the roots out of the tubes.
Ten changes were made to
insure equilibrium in the system before starting the experiment.
FIGURE
SMALL SCALE DIFFUSION BATTERY
This was necessary because fresh roots were used throughout
the system while consecutively weaker roots were in the cells
when the system was in equilibrium*
Nine more changes were
made with BOO grams of dahlias and about 2 grams of calcium
carbonate in each bottle; the liquor obtained was decolorized
by animal charcoal and filter-cell* and filtered hot.
The
filtrate was allowed to cool and the inulin was allowed to
precipitate during thirty-six hours, after which the inulin
was filtered and dried.
inulin were obtained.
Seventy-nine and one-half grams of
If it is assumed that the dahlia con­
tained 11$ inulin. which is a high value, a little over 40$
recovery of inulin was obtained.
TABLE V
DATA —
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
EXPERIMENT #2
Cells in system
8
Charge of nahlias per c e l l ......... .
BOO gm.
Total Dahlias used
................
1,800 gm.
Time of Draw • • • • . ..................
15 min.
Number of Draws per experiment. . . . . .
9
Average volume of Draw
............
150 ml.
Total inulin in Dahlias ofexperiment
. . 180 - 200 gm
Temperature in c e l l s .................. 90°
- 91° C.
Dry inulin recovered....................
Recovery................................
39.55® -
Experiment #3.
This experiment was made using the
same principles as used in experiment #2.
Eight bottles were
25
run through the battery to establish equilibrium; then* an
experiment of eight changes was made, and the liquor was clar­
ified and filtered hot as before*
The inulin solution was
evaporated to one third the volume and the Inulin was allowed
to precipitate, filtered, and dried in the drier to be describ­
ed in Ohapter IT*
Hepresentative samples of roots from the
experiment were polarized and read 10*4$ and 10*9$ inulin.
TABLE VI
DATA —
1*
8*
3*
4*
5*
6*
7*
8*
9*
10.
11*
12*
13*
EXPERIMENT #3
8
Cells in system* ........................
200
gm*
Charge of Dahlias per c e l l ........
Total Dahlias u s e d ............... * • •
1,600 gm*
Time of D r a w ............ *
15 min*
Number of Draws per experiment..........
8
150
ml*
Average volume of D r a w ............
Temperatnre in cells * * * * ............
90 - 95 C#
Average inulin content of Dahlias * . ♦ •
10.7$
Inulin in extracted roots (pulp) ........
1.'
Degree of extraction ...................
Total inulin in Dahliasof experiment • •
171 gm
Inulin recovered...................
87
gm
Recovery • • ...........................
Experiment #4*
Due to pressure difficulties that had
been encountered in the first three experiments, the pressure
system was removed and pouring from flask to flask was sub&ti
tuted*
Eight Erlenmeyer flasks were used in the experiment*
Again eight flasks were run through to bring the system to
equilibrium*
The liquor was decolorized and filtered; the
26
inulin was allowed to precipitate; it was then dried and
weighed*
TABLE VII
DATA —
1.
2*
3.
4*
6.
6*
7.
8.
9*
10.
11*
12*
13.
EXPERIMENT #4
Cells in system * « • ................
Charge of Dahlias per c e l l ..........
Total Dahlias u s e d ........ • • • • •
Time of D r a w ........................
Humber of Draws per experiment • • • •
Average volume of D r a w ........ * • •
Temperature in cells ................
Average inulin content of Dahlias * • •
Inulin content of pulp................
Degree of extraction • • • ..........
Total inulin in Dahlias ..............
Dry inulin recovered ................
Becovery • * ........................
Experiment
#5*
m
m
t
m
m
v
m
In order to check the diffusion in a
longer system, a battery of sixteen bottles was built*
These
were again immersed in a boiling water bath and pressure from
the water main was used*
Sixteen cells were run through to
bring the system to equilibrium and twenty cells were run
through in an experiment*
This experiment verifys the conten­
tion that a longer diffusion battery leads to higher extrac­
tion and higher recovery*
If the pH of the solutions were
kept lower by the addition of calcium carbonate, higher recov­
eries might be obtained*
On this experiment very few diffi­
culties were encountered and praotically no solution was lost
27
due to leaks in the system*
TABLE VIII
BATA — - EXPERIMENT #5
1.
Cells in s y s t e m ............ ...........
. • •
Total Dahlias u s e d .......... • • • • •
Time of Draw ..........................
Number of Draws per experiment ........
Average volume of D r a w ................
Average inulin content of Dahlias • • . •
Inulin content of pulp ................
Degree of extraction ..................
pH of liquor • • • • .......... • • • •
Brix of liquor at 20 C.. . . . . . . . •
Temperature in cells • • • • • • • • • •
Inulin in liquor from spent roots • • • •
Total Inulin in Dahlias of experiment • •
Dry inulin recovered • • • • • • • • • •
Recovery • • • • • • • • • • • • • . • •
2 . Average charge of Dahlias per cell
3.
4.
5.
6.
7.
8.
9.
10.
ill.
12.
13.
14.
15.
16.
16
202 gm.
4,040 gn.
30 min.
20
125 ml.
10#
0.8#
92#
5.45
14.2
90° - 95° C.
0.0#
404 gm.
255 gm.
63#
The results obtained in these diffusion attempts show
that it was possible to obtain a liquor of high inulin concen­
tration by this method.
It is also indicated that rather com­
plete extraction of the roots can be obtained at the same time,
but that more than eight cells were necessary to achieve this
result.
The extraction attained in these experiments would
indicate that a battery of twelve cells should be adequate;
this would be a very convenient number, because this is the
number of cells used by sugar beet plants in the extraction of
sucrose, and it has been the purpose of Weatherby and co-work­
ers to adapt a beet sugar plant to an inulin extraction plant
TABLE IX
COMPOSITE RESULTS OBTAINED WITH SMALL SCALE DIFB’USION BATTERY
_______
gxperiment____ _______
1
2
3
4
5
SfillS_lD_SY£lSB__ ______________ __8_______ 3______ ___ 8________ 8_______ __1S__
Average charge of Dahlias
1^0-150 _ 202
_2§r_c§ll_in_grflms_ _ _
___
200
200 _
Total Dahlias used in grgms
1^800
____________ _________ 15____
Draws per experiment
Average volume of Draw in. ml.
%
Average inulin content of Dahlias
Inulin content of gulp in
Degree of extraction in #
pH of liguor
1^600
1*160
4a040
_15___ __ 15_____- 3 0 ____
9
8
8
20
150
150
100
125
11±
10.7
10.5
10
_1*8___ _3±5___
83
66.7
0*8
__ 92_
5*45
Brix of liguor
.14*3___
o
90-100
90-91
Temperature in cells in 0.
90-95
90-95
90-95
Inulin in liquor from
spent roots in §
^pO.O
Total inulin in Dahlias
sf_expsriiDSDl-in_grflms.-________ _______ 1S0=2QQ._ — 121__ __ 122___ — 404____
Pri-iBuliD-recQyersd-ln-graas____ .22_____ 22*5___ _82___ _26*5___ _255___
£9
in its off season.
It was therefore decided to build a pilot
plant extraction battery of twelve cells with a capacity in
the neighborhood of 50 to 100 pounds of roots per hour.
III.
FILTRATION METHODS M B RESULTS
Preliminary to building a pilot plant diffusion battery,
it was considered necessary to obtain more data on the equip-*
ment necessary for handling the large quantities of liquid
which would be obtained.
Since many difficulties had been en­
countered in the filtration of inulin solutions, particularly
with reference to the removal of the decolorizing charcoal,
arrangements were made with the Dicalite Company to test fil­
tration pressures on inulin solutions using different grades
of Dicalite Filter Aid*
A solution was made of two and one
half pounds crude inulin in boiling water to mahe two gallons;
this was allowed to stand for eighteen hours.
This inulin
suspension and hot inulin solutions were filtered to determine
the most satisfactory filtration conditions.
The results are
discussed in the following paragraphs.
Controlled pressure inulin filtration. Experiment #1.
In eleven minutes £6,090 ml. of filtrate were obtained through
a press of 60 square inches of filtering area at 5 pounds per
square inch pressure.
The filtrate contained 0.07$ solids,
and the cake, which was about two thirds water, weighed 560
30
grams; the cake thickness in the filter press was one half
inoh plus or minus one thirty-second.
Filtration was at room
temperature.
Inulin filtration in small area filter press. Experi­
ment #g.
She filtration area was 1.77 square inches; 134 ml.
of filtrate were obtained in nine minutes.
one half inch thick*
She cake was about
She pressure varied from 0 to 30 pounds;
higher pressures did not appreciably increase the rate of fil­
tration.
She cake was gummy which indicated that the use of
filter aid would be necessary in the filtration of crude inulin.
Filtration of hot, crude inulin solution to remove fil­
ter cell and decolorizing charcoal*
A solution was made using
1.350 grams of crude inulin in two gallons of hot water; 135
grams of Dicalite Special Speed Flow and 13.5 grams of Norite
were added.
Shis solution was used in the following experi­
ments.
Experiment #3*
precoat of Speed Flow.
trate were obtained.
She solution was filtered through a
In twenty-one minutes 975 ml. of fil­
She filtering area was 1.77 square inches
and the pressure varied from 5 to 40 pounds*
31
TABLE X
FILTRATION TIME VS. PRESSURE
minutes
pressure
3
6
9
IS
16
£1
filtrate in ml.
5 lbs.
10 "
£0 *
30 11
40 *
40 "
£70 ml.
430 "
600 *
737 "
836 "
975 "
A five ounce sample of filtrate contained S3.5 grams of inulin.
Experiment #4.
The filter area was 60 square inches.
The solution was filtered through a preooat of Speed Flow.
In one and one half minutes 1,665 ml were obtained at a tern*
perature of 91° C. under 10 pounds pressure.
A six ounce
sample of filtrate contained £5 grams of inulin; this inulin
filtered slowly.
Experiment #5.
The solution was prefiltered through
Special Speed Flow; then, 1$ Norite and 1$ Speed Flow were
added.
In fifteen minutes 870 ml. of filtrate were obtained
at a temperature of 91° 0.
inches.
The filtering area was 1.77 square
An eight ounce sample of filtrate contained £8 grams
of inulin; the inulin filtered slowly.
32
TABLE XI
PILTRATIOR T i m VS. PRESSURE
minutes
pressure
filtrate in ml.
10 lbs.
20 »#
30 it
40 tt
40 n
3
6
9
12
15
Experiment # 6 .
110 ml.
280 n
495 n
725 tt
870 IT
The solution was prefiltered through
Special Speed Plow; 1$ Rorite and 1?S Special Speed Plow were
added, and this solution was filtered using a press of 60
square inches filtering area.
The filtering time was two min­
utes at a temperature of 90° C.; 1,300 ml. of filtrate were
obtained.
The maximum pressure was 10 pounds per square inch.
Six and one half ounces of filtrate contained 37 grams of in­
ulin; this inulin filtered well.
These filtration results
all indicate that it is advisable, when filtering crude inulin,
to add about
Speed Plow.
of filter aid of the type of Dicalite Special
This filter aid is a calcined diatomaceous earth
and is designed to give fast filtration.
It is not necessary
to prefilter the solutions before adding Rorite, but higher
Rorite economy is obtained by this method.
It is advisable,
in using Rorite, to add it several minutes previous to the
addition of the filter aid because the filter aid tends to
33
TABLE XII
COMPOSITE RESULTS OF FILTRATION OF
HOT INULIN SOLUTIONS
# of experiment
Filtering time
in minutes
Maximum pressure
in pounds
3
4
5
6
21
1.5
15
2
40
10
40
10
975
1.165
870
1.300
Filtrate in ml.
grams inulin/
100 ml. solution
Area of filter press
in sauare inches
15.9
14.1
11.9
19.3
1.77
60
1.77
60
Type of preooat
S.F.*
S.F.*
S.F.*
S.F.*
1S.S.F.**
S.S.F.**
S.F.*
S.S.F.**
1.0
0.0
1.0
1.0
92
91
91
90
adsorb the Norite and decrease its efficiency.
About 1$
Type of filter aid
% Norite
Temperature °C.
S.F.*
S.S.F.
Speed Flow
---Special Speed Flow
Norite, based on the dry weight of inulin, is usually adequate
to remove all coloring matter from the crude inulin from the
diffusion battery.
4
CHAPTER IV
CONSTRUCTION OF PILOT PLANT
I.
MATERIALS OF CONSTRUCTION
It was desired to construct a battery having a capacity
of 50 to 100 pounds of dahlia roots per hour*
The presence of
tannins in the dahlia roots makes the use of iron containers
impractical due to the formation of inks.
Tests were made on
the solubility of copper and tin in solutions of the juice
from the dahlias.
After ten hours of boiling copper turnings
with dahlia roots no test for copper in the solution, was ob­
tainable.
Similar results were obtained when tin was subjected
to this treatment.
However, when dahlia roots were boiled with
copper plus tin, a trace of tin was detected.
Therefore, it
was decided that containers constructed wholly of copper or
tin would be satisfactory, but it would be advisable to avoid
the use of both in contact with the roots.
Lata were collected
on the costs of construction of suitable containers of copper
and/or copper alloys.
To force the diffusion liquid through
the battery, in a small scale operation it has been shown that
pressures as high as 60 pounds might be necessary.
Therefore,
it was considered advisable to build a battery capable of
withstanding pressures as high as 125 pounds.
The cost of
building such cells wholly of copper would have been prohib­
35
itive*
Building the cells of iron and electroplating them
was suggested, hut this plan was discarded because of the pos­
sibility of small exposures which would interfeafc with the pur­
ity of the product*
fhe use of ice-cream cans, which are of
sufficiently heavy construction to withstand the pressure and
are heavily tinned, was suggested*
fhe use of these contain­
ers would require that the connecting tubes be made of block
tin or of iron tinned on the inside*
However, tinners will
not tin the inside of small tubing because of the dangers of
explosion*
It was desirable to avoid the use of block tin
tubing, if possible, because of the softness of the material*
However, after extensive searching, no other satisfactory
tubing was found, and it was decided to use a heavy, block tin
tubing*
Half-inch block tin tubing of a weight of 6 ounces
per foot is capable of withstanding a pressure of 600 pounds;
it is fairly soft, readily worked, and, with care, can be
handled successfully*
fhe next problem was the heating of the solutions, and
steam coils were the obvious means of accomplishing this*
Since the steam coils could be mounted on the outside of the
containers and thus avoid contact with the roots, malleable
copper tubing seemed the best material of construction*
It
was not possible to calculate the amount of contact surface
necessary, but the estimates obtained from the Chemical Engi-
36
nee ring Department indicated that six or seven tarns of halfinoh copper tubing around each cell would probably be satis­
factory*
I'rom calculations based upon the sige of the con-
tainers, it was estimated that about sixteen feet of tubing
would be necessary for each cell*
The copper tubing was avail­
able in twenty-foot lengths which allowed extra tubing for con­
nections*
It was estimated that a flat top, for the container,
capable of withstanding pressures of 60 pounds, would have to
be of one fourth to three eighths inch iron; this lid would
also have to be tinned*
To check this estimate a trial con­
tainer was built to meet these specifications.
It was tested
and found to have a factor of safety greater than two.
In
order to hold this lid in place, it was planned that eight
strap iron lugs would be riveted to the can, and bolts insert­
ed in the lugs through corresponding holes in the lid*
The
lid then could be secured by wing-nuts.
Estimates were obtained for the construction and tin­
ning of the lids, the building of the lugs, and the insertion
of the tin tubing into the bottom of the container and into
the lid*
When this work was completed the steam colls were
bent into shape around a circular block of wood one inch small­
er in diameter than the containers; these coils were then
sprung upon the cans and soldered in place; the ends of the
37
Figure 3*
Inner Cell (Upside down)
c
•
Container
LOT
-
Liguor Outlet Tube
L
-
Luge
SIS
-
Steam Inlet Tube
SOS
-
Steam Outlet Tube
ST
-
Steam Tubing
37
FIGUBB 3
38
coiled tubes were bent out perpendicular to the sides of the
can by means of a bending tool(Figure 3)*
II.
THE CELL
It was next necessary to determine a means of insulat­
ing the units.
Many insulating materials were available, but
the simplest one that seemed satisfactory was rock wool.
The
insulating material had to be held away from the steam coils
lest it reduce conductivity of the heat.
Cans having a suit­
able diameter to fit over the steam coils, were purchased.
These were put over the coils and the whole supported in a
box (Figure s 4, 5, & 6).
The top of the outer can was flared
and nailed to the top of the box(Figure 7).
The space between
the outer can and the walls of the box was then filled with
rock wool.
The thickness of the insulating material was one
inch in the thinnest places and was packed to a density of IB
pounds per cubic foot (Figures 4 & 5).
The insulation box was
built with a false bottom to allow for a fitting on the end
of the tin outlet tube(Figure 4).
This was to facilitate
cleaning of the connection lines in ease any plugging occurred.
Tin tubing was cut to length, filled with sand, and bent to
shape to connect the outlet tube of one cell to the intake
tube of the next.
The connections in the tin tubing were made
by means of flared fittings.
heavily tinned.
The couplings were made of brass,
ft
to
,0000 o
•rt
;zz:z 's~2fs-sizjzzs:sy*\
LOl
40
S c a / e - . / ’= «3 ”
End View
FIGURE 5.
*9 U A D U
P**s
;d/oof
m*u
*1*
L
It
i
4Z
Figure 7*
Diffusion Cell —
Open
FS
- Filter Sack
IS
- Insulation Space
Id
- Lid
LI3?
- Liquor Inlet Tube
L
- Lug
SCS
- Steam Chamber Seal
SGCC
- Steam Coil Coyer Can
SIT
- Steam Inlet Tube
SOT
- Steam Outlet Tube
42
FIGURE 7
43
To facilitate rapid operation it was necessary to leave
about two inches of the top of the can above the box(3?igure 8)*
To Insulate this large area and the surface of the can tops a
cover box was constructed; this had a doable top to allow for
insolation(Figure 9)*
So insulate the sides of the cover box,
a coarse, matting material was obtained and tacked in place*
A small space had been left between the insulation box top
and the walls of the diffusion cell*
So prevent the entrance
of water into this space and the loss of heat, a mixture of
cement and asbestos was pressed in place*
well insulated, waterproof unit*
Shis gave a compact,
The boxes were varnished and
painted with aluminum paint to protect the wood*
It was necessary to have some type of removable con­
tainer within the cell to hold the roots, keep them from en­
tering and plugging the lines, and to make it possible to re­
move the spent roots without too much wasted labor.
Many
types of containers were considered and it was decided that
a sack made of ooarse filter cloth would be satisfactory*
fhese sacks were made with a flared top to fit over the top
of the cell (figure 10}*
Hight holes were made in the flared
top to fit over the bolts that held the lids in place thus
holding the sack firmly in place*
It was found by a prelim­
inary test that this canvas material did not serve as an ade­
quate gasket to hold the pressure*
Gaskets were made by cut-
44
figure 8*
Diffusion Cell
IS
-
Insulation Spaoe
Li
-
Lid
LIT
-
Liquor Inlet Tube
L
-
Lug
SCS
-
Steam Chamber Seal
SCCC
-
Steam Coil Coyer Can
SIT
-
Steam Inlet Tube
SOT
-
Steam Outlet Tube
m
-
Wing Wuts
44
FIGURE 8.
45
Figaro 9*
Complete Diffusion Cell showing Insul­
ation areas
DCC
-
Diffusion Cell Cover
IS
•»
Insolation Space
Li
-
Lid
LIT
w
Liquor Inlet Tube
L
-
Lug
SOS
mm
Steam Chamber Seal
SCCC
-
Steam Coil Cover Can
SIT
-
Steam Inlet Tabe
Steam Outlet Tube
SOT
WN
•
Wing UutB
45
FIGURE 9.
46
Figure 10*
Filter Sack
47
ting rings of graphite-asbestos gasket material,
These were
about one thirty-second of an inch in thickness and were en­
tirely satisfactory.
It was found, after the preliminary ex­
periment with this set up, that the filter cloth sacks were
too finely woven; when the material clogged with fine solids,
the back pressure developed to such an extent that operation
difficulties occurred.
A new set of sacks were made using the
same pattern but of unbleached muslin to allow faster flow.
These were quite satisfactory and were used for the remainder
of the experiments.
III.
ASSEMBLY
The steam from the steam boiler was connected to the
steam main and the steam inlet lines were run off from this
line in parallel.
The drips lines were connected to the drips
main in a similar fashion*
compression fittings.
All connections were made using
A steam trap was connected to the drips
line and a pipe was run from this to a container for measuring
the condensate.
It was later decided to use the condensate
container as a preheater for the water inlet line to the dif­
fusion battery.
The water inlet line was run directly from
the water main to the preheater, at whioh point a needle valve
was inserted to allow fine control of the flow.
From the pre-
heater the water line was run to the center of the diffusion
battery, which was arranged in a circle, where a rubber hose
46
was connected so that the inlet oould be readily attached to
any cell in the system(Figures 11 & IB)*
twelve of the four­
teen cells would be connected together with a rubber hose con­
nected to the outlet of the twelfth cell.
Shis rubber, out­
let hose was run to a water cooled trough operating on the
counter-current principle for the cooling of the diffusion
liquid.
From the outlet of this trough the liquor dropped in­
to a graduated container to measure the quantity of each draw*
The two cells not in the system were to be used for emptyii^g,
cleaning, and refilling.
IV.
AUXILIARY APPARATUS
Cutter(Figure 13).
In building a diffusion battery on
the desired scale, it was necessary to obtain a cutting ma­
chine of adequate size with relatively easy operation.
were made on the rate of cutting of several machines.
Tests
A large
power meat grinder was tried, but the fibers in the roots
covered the cutting edges after a few pounds had been forced
through and stopped the operation.
Several vegetable cutting
machines and shredders were next tried, but in all cases cut­
ting edges were soon obstructed by fibers.
Attempts were made
to obtain a beet sug§r, cossette cutter, but small ones were
not available.
At this point a vegetable cutter, manufactured
by J. 1, Smith and Sons of Buffalo, Rew York, was suggested
and on trial proved quite adequate.
It was found that about
49
Pigure 11*
Pilot Plant Diffusion Battery opened
CP
-
Conneoting Pubes
DL
-
Drips Line
HWL
-
Hot Water Line
IHV
-
Inlet Heedle Valve
ISY
-
Inlet Steam Valve
OSV
-
Outlet Steam Valve
P
-
Preheater
SL
-
Steam Line
PW
thermometer Welle
49
DLSL -
tiWL
FIGURE 11.
T op
V i® W
of
Diffusion
Battery
|«T< r
t=l
FIGURE 13.
51
figure 13*
Cutting Machine and Pilot Plant Bif
fusion Battery In operation
CM
-
Cutting Machine
13?
-
Insulating fop
101
-
Liquor Outlet Line
P
-
Preheater
BOB
-
Botary Cutter Bowl
51
FIGURE 13.
52
150 pounds of dahlia roots per hour could be cut in a machine
with a fourteen inch bowl.
One of these machines, with a six­
teen inch bowl, was obtained*
£his machine is designed to be
emptied by hand, but this was considered too dangerous so a
curved piece of cardboard was cut to be used for the removal
of the roots,
^his machine was used throughout the experiments
with complete satisfaction.
Filter press.
A plate and frame filter press with
twelve by twelve plates was available.
3!his type of filter
press can be used on small scale work where washing is unneces­
sary and where it is not required that the cake be easily and
quickly removed.
Since no other filter press was obtainable,
this had to be used.
It is suggested that an Oliver Continuous
Filter Press would prove much more satisfactory.
A three quar­
ter inch bronze gear pump was also available; this was capable
of developing heads up to 60 pounds with a satisfactory volume
of flow.
A pump of sturdier construction would be more satis­
factory because the filtrations of the suspensions of diatomaceous earth wear a pump of this design and require frequent
replacements.
Hevertheless, for small plants, this pump is
inexpensive and adequate.
Air compressor.
In filtering the inulin suspension
it
was necessary to blow the cake dry with compressed air before
its removal.
Otherwise the cake was so wet and gummy that
53
removal was too slow*
An air compressor had to he obtained
to perform this operation*
]?• E. Holmes of 665 Del Monte
Street, Pasadena, has constructed and patented an air compres­
sor of radical design which has several obvious advantages
over the accepted types of air compressors*
It is capable of
developing heads of 100 pounds per square inch without the
disadvantage of pulsating flow of a reciprocal pump or the
fine clearance required for a centrifugal pump*
The pump has
an infinitely variable displacement at constant speed, and it
is built with only three moving parts all of which are rotary*
Since the compression chambers rotate, it is not necessary to
provide any cooling system because a stream of air is carrie d
over the compressor by its motion dissipating its heat by con­
vection*
It is capable of producing a rather large volume of
air per pound weight of pump and has been found to be quite
satisfactory in our experiments*
Steam generator* A small vertical tube steam generator
was available*
It was designed to develop steam as high as
100 pounds pressure and had an output of 5 horsepower.
An
iron pipe was run from this generator to the diffusion battery
and this was purposely not insulated in order that wet steam
only would be used*
SEhus, the danger of superheated steam
with temperatures higher than those calculated from the steam
pressure was avoided.
A little difficulty was encountered
in attempting to fceep the steam pressure constant, but this
54
ooold be overcome with practice or the insertion of a needle
valve in the gas line.
In all other respects, this generator
was quite satisfactory.
Drier. After the inulin had been filtered and blown
as dry as possible in the filter press, the cake still con­
tained approximately two-thirds water.
For this reason a
shelf drier with a fan and heating coils had been constructed
several years ago for the purpose of drying similar inulin
cakes.
The fan was mounted at one end of a tunnel which con­
tained the heating elements; this tunnel led into a shelf com­
partment.
The construction was simple, but it was quite satis­
factory for 10 to 15 pounds of inulin at a time.
When fully
loaded, the drier would dry the cake in about twenty-four hours.
Miscellaneous equipment.
Other equipment that was
necessary in a plant of this size included various containers
and a set of hot plates.
It was found that several buckets
should be included in the equipment to facilitate the handling
of solutions.
For large quantities of liquor and pulp six 50-
gallon drums were obtained.
blue scale linings.
These drums were of iron, with
These would not be satisfactory because
the iron would rust even with the covering of blue scale.
It
was therefore necessary to obtain some covering that would be
non-poisonous and unaffected by the solution.
Most paints or
enamels would tend to peel when in contact with hot solutions.
55
The Amerioan Concrete and Steel Pipe Company kindly famished
two gallons of their special acid and alkali resisting enamel
which served to coat the drums on the inside; this enamel
holds very well under the conditions used and was more satis­
factory than any other container with the possible exception
of stainless steel or aluminum.
Paint.
"Amercoat11 is a chemically resistant coating
manufactured and marketed by the American Concrete and Steel
Pipe Company of South Cate, California.
It resists the cor­
rosive action of practically all inorganic solutions except
concentrated nitric and sulfuric acids.
It also resists the
action of most organic solvents except the lower fatty acids,
aldehydes, ketones, esters, chlorinated hydrocarbons, and
the ring compounds.
It is sufficiently hard to withstand a
considerable amount of abrasion and yet is plastic enough
not to check, crack, or fracture when subjected to vibration
or shock.
In order to heat the liquor for the hot filtration
necessary for purification, several tin-lined copper boilers
were obtained.
Gras hot plates were used as a source of heat.
To purify the inulin, it was necessary to remove plant
dyes which were extracted in the process.
To accomplish this
1fo of Uorite and 1$ Dioalite were added to the solution.
56
These were filtered from the hot solution after one half hour
of heating*
For this operation 15 pounds of Norite and 100
pounds of Dicalite were obtained*
Dicalite is also added to
slimy, Inulin precipitates to facilitate their filtration*
Shis Dioalite was removed in the succeeding hot filtration*
CHABTBB V
DIFFUSIOK STUDIES OK A PILOT BLAST SCALE
Before starting a preliminary diffusion study the appar­
atus was cheeked for possible difficulties.
The apparatus was
set up as for an experiment, the steam generator started, and
water was run through the system to test for possible leaks
and to determine the rate of flow,
A few leaks were found in
the steam lines, but these were stopped by tightening the fit­
tings*
ho leaks developed in the battery itself and water
flowed through very readily.
The steam colls proved to
be en­
tirely adequate, as the temperature of the system could be
raised to 90° C, or above in less than half an hour.
It was found that about 10 pounds of cut dahliaroots
were a suitable charge for each cell*
This was adopted for
the standard charge throughout this experiment*
It was desir­
able to obtain a liquor containing as high a concentration of
Inulin as possible.
cipitate readily.
If it is above 15%, the inulin will pre­
Since preliminary investigations had indi­
cated that most of our dahlia roots would average 10% inulin,
a draw of about three and one third quarts for each cell should
give approximately this concentration.
Twelve cells were fill­
ed with cut roots and water, and the trial experiment was
started.
58
Experiment #1.
Uine changes were made*
The changes
were to he at half hoar intervals, hat after the first two
draws were made, a back pressure developed to such an extent
that the fall pressure of the water main, 60 to 70 pounds per
square inch, was not enough to force sufficient liquid through
in a half hour*
Three and one half quarts of liquor obtained
were considered the draw*
A new cell was then added and five
more quarts of liquor were then forced through to fill this
cell before removing the spent cell.
Five quarts of dilute
solution were discarded each time with the spent fibers, but
tests on the concentration of this solution showed that the
inulin losses were negligible*
By operating the system at
maximum pressure, it was possible to complete an experiment
of nine changes, but it was not possible to make the changes
every half hour*
The time of changes varied from one half
hour to one hour and fifteen minutes*
At this point it was decided to discontinue operation
and attempt to eliminate the cause of the back pressure.
How­
ever, the system was approaching equilibrium and sampling of
the spent roots and
the liquor being obtained would indicate
the efficiency of the system under equilibrium conditions*
Two samples eaoh were taken from; 1) the original roots, 2)
the last draw, and 3) the most completely extracted roots*
Since the system was in a state comparable to equilibrium the
59
last draw was a liquor containing inulin approaching the con­
centration of the equilibrium liquor* similarly, the spent
roots were extracted nearly as completely as those from the
system in equilibrium.
fhe samples, 16.8 grams each, were to be analyzed by
the modified sugar beet method.
Since this method assumes,
in the case of roots and extracted roots, which will for con­
venience be refe^ed to as pulp in subsequent references, 10.8
grams of water per sample; it was considered advisable to take
samples to be dried in order to check the slight variation in
this assumption,
therefore, two 60 gram samples of roots and
two 60 gram samples of pulp were taken for analysis of water
eontent.
It was later decided to ash one of each of these
samples as an added check on the variation in roots and as a
check on the extraction of salts.
fhe specific gravity of the last draw was tested with
the Brix spindle and found to be 10 Brix.
Since a solution
of 10 Brix is rather dilute for inulin recovery, 50 pounds
of fresh roots were added to the liquor and boiled in a boiler
for one half hour, then pressed in a cider press to remove
the solution and allow recovery of the inulin.
All the sol­
utions were very dark, indicating that long boiling probably
removes much of the tannin,
fhe solution was set aside to
allow the inulin to precipitate.
60
All of the palp was now removed from the battery.
It
was found that the pressure had forced the bottom of the sack
against the bottom of the cell, pushing a small section of the
sack into the outlet and reducing filtration area to about one
square inch#
It was decided that a barrier should be construct
ed which would separate the bottom of the sack from the bottom
of the cell and allow free flow of the solution.
Various ma­
terials of construction were considered and ridged mahogany
discs were finally selected(Figure 14).
fhese were heavily
varnished to protect the wood from the boiling water.
Experiment #8.
The results of experiment #1 showed
that more roots per cell would give a more satisfactory sol­
ution, so 15 pounds of roots were used in each cell in this
experiment.
It was decided to attempt to make a change every
twenty minutes in this experiment.
With the new wooden discs
in the system, operation was more satisfactory and experiment
#8 was started.
In order to obtain concentrated liquor from
the start, water was run through it and the solution was ran
into cell #8 until it was filled; this process was continued
until the whole battery of twelve cells was filled#
Since
the battery contained fresh roots throughout, the resultant
solution would be more concentrated than an equilibrium sol­
ution.
Consequently twelve changes were made to bring the
system to equilibrium, after which the true "experiment” was
begun and data were collected.
Fifteen grams of CaCOg were
Figure 14•
Mahogany Disc
61
FIGURE 14
62
added to each 15 pounds of roots to reduce acidity.
As the experiment progressed, hack pressure again de­
veloped and twenty minute changes were possible only through
the first five draws.
four minutes.
The average time per draw was twenty-
Samples of solution were taken from alternate
draws for Brix: readings and analysis.
Samples of roots and
pulp were also taken for analysis and for determinations of
water content and ash.
A record of the cell temperatures, as
well as steam boiler pressures, was kept throughout the ex­
periment.
It was desired in this experiment to collect two
and one half quarts of solution per draw, but it was found
that a large lag occurred between adjustment of water pressure
and rate of flow of the outcoming liquor.
It was impossible,
consequently, to control the volumes of the draws,
ied from two and one half quarts to six quarts.
They var­
The average
volume per draw was four and one fourth quarts.
Experiment #g.
To avoid the difficulties of experiment
#2, new filter sacks were made of unbleached muslin which is
a much more porous cloth, and as was expected, maintenance
of flow was easier.
in the system.
The experiment was made with twelve cells
Fifteen pounds of roots were used in each cell
and about two and one half to three quarts of liquor were col­
lected per draw.
Sixty-seven and one half grams, 1$, of cal­
cium carbonate were added with each 15 pounds of roots.
TABLE XIII
63
EXPERIMENT #2
12 CELLS —
26 MIN* PER DRAW
*Craw Draw Draw Draw Craw Craw Craw Craw Craw
*
#2
#3
#4
#5
#6
#7
#8
#9
* #1
fime of braw ’
in minutes
Volume of Draw
in auarts
Average dell0
Temperature C.
Brix of Draw
Inulin floho.
in per cent
Quantitative
Benedict’s
Pulp Sample
in grams
Inulin Co'nc #
in per oent
Quantitative
Benedict’s
Dry Weight of
Pulp in grams
Ash of Pulp
in per cent
Root Sample
in grams
Inulin done*
in per oent
Pulp Sample
in grams
Hoot Sample
in grams
Bry Weight of
Roots in grams
Ash of Roots
in per oent
Extraction %
20
20
20
25
25
35
35
30
25
4*0
6.0
6.0
3 f0
3.0
4.0
4.0
2.5
3.5
91
90
47
78
66
84
78
12.0
11.5
11.4
12.7
10.3
5*0
6.1
5.7
6*9
5.9
37.6
37.6
37.6
37.6
37.6
0.6
0*6
0.8
0.1
0.5
1.49
1.35
1.85
1.39
1.39
18.8
18.8
20.0
20*0
20.0
20.0
20.0
20.0
18.8
18.8
18.8
6.9
7.4
7.4
20*0
20.0
20.0
20.0
3.81
91*5
3.72
92.0
4*04
89.0
3.93
98.8
3.96
94.0
TABLE XIV
64
EXPERIMENT #3
12 CELLS —
22 MIR♦ PER DRAW
*Draw Draw Draw Draw Draw Draw Draw Draw Draw
*
#1
#2
#3
#4
#8
#6
#7
#8
#9
*1*
Time of Draw
in minutes
Volume of Draw
in auart8
Average bell
Temperature C.
Brix of Draw
Draw Sample
in grams
Inulin Cone,
in per oent
Quantitative
Benedict1s
Pulp Sample
in grams
Inulin Cone,
in per oent
5ry Weight of
Pulp in grams
Ash of £ulp
in per oent
Rooi Sample
in grams
Inulin Coho,
in per oent
Quantitative
Benedict’s
Pulp Sample
in grams
Soot Sample
in grams
Dry Weight of
Roots in grams
Ash of hoots
in per oent
Extraction %
25
20
20
20
20
20
30
20
25
3.0
2.6
4.0
4.0
3.5
4.0
2.5
4.0
8.5
90
66
91
?1
91
94
89
92
92
,
11.2
9.6
10.0
10.0
10.1
18.8
18.8
18.8
18.8
18.8
7.3
6.9
7.1
7.3
6.3
37.6
37.6
37.6
37.6
37.6
0.1
0.0
0.7
0.0
0.4
1.37
1.32
1.17
1.07
1.07
0.430
18.8
18.8
18.8
18.6
18.8
7.6
7.6
9.3
8.1
7.9
7.0
20.0
20.0
20.0
20.0
20.0
20.0
20.0
20.0
20.0
20.0
3.07
2.98
3.13
3.74
1.040
98.8
100.0
92.5
3.05
1.181
100.0
95.0
65
Twelve changes of cells were made to bring the system to equi­
librium after which the experiment was begun*
Samples of
roots* solution* and pulp were taken from every alternate draw
throughout the experiment in order to determine the efficiency*
The experiment involved nine changes*
The conditions of experiments #4 and #5 were the same
as those of experiment #3 except that experiment #4 employed
a system of ten cells and experiment #5 used a system of eight
cells* while #3 was operated with a system of twelve cells*
Experiment #6*
It was desirable to compare sodium bi­
carbonate with calcium carbonate in controlling acidity in an
experiment of this kind*
It was expected from previous exper­
imentation that darker inulin* of an inferior grade* would be
produced through the use of sodium bicarbonate* but that this
inulin would be filtered more easily*
This experiment was for
the purpose of checking these assumptions*
The conditions of
this experiment were similar to those of experiments #3* #4*
and #5 except that one half of 1# sodium bicarbonate was used
in place of Vjt> calcium carbonate*
The system was not brought
to equilibrium before starting the experiment because of a
shortage of roots.
i*or this reason quantitative data on ex­
traction would have no meaning.
Eowever* for comparison of
the types of inulin obtained, the experiment was entirely
satisfactory*
Twelve cells were filled with roots, and the
TABLE XV
66
EXPERIMENT #4
XO CELLS --- 20 Mil. PER DRAW
*
*
*
Draw
#3
*
*
*
Draw
#4
*
*
*
Draw
#6
16
20
20
26
15
6.0
6.0
2.6
2.5
4.0
92
90
85
90
91
18.8
18.8
18.8
.
18.8
9.9
10.0
10.6
CD
Extraction %
Draw
#2
GO
H
Brix of Draw
braw Sample
in grams
inulin Cono.
in per oent
Quantitative
Benedict*s
Pulp Sample
in grams
Inulin dono.
in per oent
Quantitative
Benedict's
bry Weight of
Pulp in grams
Ash o£ Pulp
in per oent
Soot Sample
in grams
Inulin done,
in per oent
Quantitative
Benedict's
Pulp Sample
in grams
Hoot Sample
in grams
bry Weight of
Roots in grams
Ash of Hoots
in per cent
*
*
*
7.5
7.7
37.6
37.6
37.6
0.0
0.1
0.2
7.6
9.4
Not significant
1.07
0.93
1*066
.
a?
Tim© of Draw
in minutes
Volume of Draw
in auarts
Average Ceil
Temperature C.
Draw
#1
18.8
8.4
8.1
20.0
20.0
20.0
20.0
20.0
20.0
18.8
8.0
H
03
*
*
*
9.0
3.26
3.17
1.090
100.0
2.71
— 1*106
98.8
97.5
67
TABLE XVI
EXPERIMENT #5
8 CELLS —
*
*
*
Tim© of Draw
in minutes
Volume of Draw
in Quarts
Irerag© d©ll
Temperature °C.
Brix of Draw
Draw Sample
in grams
Inulin Cfono*
in per oent
Quantitative
Benedict *s
tul'p Sample
in grams
inulin 6 one.
in per cent
Quantitative
Benedict1s
Ery Weight of
Pulp in grams
isk of Pulp
in per cent
boot Sample
in grams
inulin done*
in per oent
Quantitative
Benedict1s
Eulp Sample
in grams
Hoof Sample
in grams
l>ry Weight of
Boots in grams
i!sk of Hoots
in per cent
Extraction %
Draw
*
*
25 MIN. PEB DRAW
Draw
#2
*
*
*
Draw
#3
*
*
*
Draw
*
*
Draw
#6
:
SO
30
25
20
20
4*0
2.5
2.6
4.0
6.0
86
90
90
83
88
9*6
9.5
8.9
18.8
18.8
18.8
7.2
6.9
7.1
37.6
37.6
37.6
0.0
0.3
0.4
7.5
Not significant
1.09
1.12
1.24
1.590
1.800 __
18.8
18.8
18.8
8.1
7.1
6.8
20.0
20.0
20.0
20.0
20.0
20.0
8.8
3.36
3.10
1.235
1.055
100.0
3.25
95.7
94.0
68
experiment was immediately started*
Five changes were made
and water was continued running through the system until the
liqupr obtained dropped to a concentration of less than 8 Brix*
The liquor obtained was treated in the same manner as those in
experiments #3, #4, and #5; it was allowed to stand for an in­
terval of thirty-six to forty-eight hours and the inulin was
removed by filtration and dried*
It was somewhat darker than
that from calcium carbonate experiments, but it was not appre­
ciably easier to filter*
From this it would appear that so­
dium bicarbonate offered no appreciable advantage and had some
di sadvantages•
Extraction curve of cells in system*
Upon the comple­
tion of experiment #5, the system was disconnected and pulp
samples were removed from each cell in the system in order to
determine the degree of extraction in the consecutive cells
of the system*
Samples were analyzed for inulin plus sugar,
while other samples were analyzed for water content and ash*
Cell #1 was the cell containing the freshest roots, and cell
#8 contained the roots which were most completely spent*
fhe results of this experiment are given in fable XVII, and
Figure 16*
fI
All
'E-i
±1
: ie:
69
TABLE XVII
DETERMIH ATIONS FOR EXTRACT!OH CURVE
# of Cell * $ Inulin
*
*
*
Pulp
* Sample
* in &rams
*
Dry
* Weight
* in «:rams
1
5.5
30.0
3.220
2
4.2
30*0
2*455
3
3*4
30.0
2.470
4
1*4
30.0
2.550
5
0.85
30.0
1.880
6
0*8
20.0
1.890
7
0*55
20.0
1.650
a
0*5
20*0
1.650
cell
*
*
Ash
per cent
1.07
1.21
1.13
#1 -- Quantitative Benedict's — - 6.75fo
The average original inulin content of these roots was
in the neighborhood of 7*3$ which indicates an inulin extrac­
tion of aboat 93$ under the conditions of this experiment.
Therefore* with roots cut to a rather small size, a battery
of eight cells gave sufficiently complete extraction for all
practical purposes.
However, the number of cells required in
the system will vary with the time of each draw and with the
subdivision of the roots.
If the roots were sliced or shred­
ded only, more cells were required to achieve this degree of
extraction with the same conditions of time, temperature, and
70
flow*
For general purposes of extraction using a cutting ma­
chine* eight cells should usually he sufficient.
Determination of hydrolysis of crude inulin*
Determin­
ations have been made on the hydrolysis of purified inulin in
boiling water under various pH conditions*0
However, it was
considered advisable to make a check of the hydrolysis of
crude inulin as obtained from the diffusion battery, because
this would be more comparable to the conditions existing in
the battery.
Six 40 gram samples of dry inulin were taken
from experiment #3,
way,
fhis inulin had not been purified in any
Each sample was dissolved in 200 ml, of boiling water
and placed in a boiling water bath under air reflux.
Samples
#1 and #2 were removed after ten minutes; #3 and #4 after
thirty minutes, and #5 and #6 after three hours,
fhe inulin
was allowed to precipitate during forty-eight hours, after
which the samples were filtered and dried*
She results of these determinations showed that rather
large leased occurred in all cases*
fhe increased loss with
Increased time was small as compared to the initial loss.
From this it would appear that slightly lower losses of in­
ulin can be expected if it is in the battery for a shorter
period of time, but the increased loss with the slight increase
in time is not large.
It is possible then that the increased
extraction with the increase in time might more than balance
71
2ABLE XVIII
PEfERMINATI OH OF HYPROLYSIS OF CRUPE INULIN
Weight * Average
Lost
^Weight Lost
in grams
_
Number of * Weight of * fime in
*
Sample
Sample
Bath
* in grams * in min* * in grams *
1
40*0
10
5*85
z
40.0
10
5. 26
3
40.0
30
7*06
4
40*0
30
6*43
&
40*0
180
6
40*0
180
the losses through hydrolysis*
____
7*60
5*65
6.75
7*62
7*63
In order to determine optimum
conditions for inulin extraction it will be necessary to carry
out a great many diffusion studies*
Shese studies will prob­
ably not be completed until the process is in commercial use*
Experiment # 7 *
It was considered necessary to determine
the obtainable yield if a battery of eight cells were run much
more rapidly than in the previous experiments.
In order to do
this changes in construction to facilitate rapid operation were
imperative*
Hose couplings replaced the flared fittings* and
sacks with screen bottoms replaced the filter cloth sacks of
former determinations*
A clamp was placed on the rubber hose
to serve as a valve to stop the flow of liquor during changes.
72
TABLE XIX
EXPERIMENT #7
8 CELLS
10 MIN. PER DRAW
*Praw *Braw *Praw *Praw *Braw *Braw *Praw
: #x *
* #4 *
* #5 *
* #6 *
* #2 *
* #3 *
Time of Draw
in minutes
Volume of Brew
in quarts
Average deli
Temperature C.
Brix of Draw
Draw Sample
in grams
Inulin tiono.
in per oent
Quantitative
Benedictfs
Pulp Sample
in grams
I&tilin done,
in per oent
Quantitative
Benedict1s
Pry Weight of
Pulp in grams
Ash of Pulp
in per cent
Root Sample
in grams
inulin Cone,
in per oent
Quantitative
Benedict vs
Pulp Sample
in grams
Root Sample
in grams
Pry Weight of
Roots in grams
Ash of Roots
in per cent
Extraction %
10
10
10
10
10
10
5
2.7
2.7
3.2
2.7
2.7
2.7
4.3
18.8
18.8
18.8
18.8
90 - 95
12.2
18.8
18.8
18.8
6.6
8.6
7.5
6.9
37.6
37.6
37.6
37.6
1.2
1.2
0.5
0.5
1.766
1.640
1.530
1.280
18.8
18.8
18.8
18.8
9.1
9.1
10.6
10.6
20.0
20.0
20.0
20.0
20.0
20.0
20.0
20.0
3.68
87.0
3.16
87.0
3.72
95.0
3.92
95.0
73
With this equipment ten minute changes were made and satis­
factory control of liquor flow was possible*
An experiment
of seven changes was made after bringing the system to equilib­
rium in the usual manner*
Charges of 15 pounds of roots per
cell were used throughout the experiment*
and analyzed as in previous experiments*
Samples were taken
fhis experiment in­
dicated that operation at such a rapid rate is not so satis­
factory as when changes are made at twenty minute intervals*
One per oent calcium carbonate was used to control the acidity
of the solutions*
She quality of the inulin obtained was not
noticeably different from that obtained in other experiments
in Which calcium carbonate was used*
74
TABLE XX
COMPOSITE RESULTS OF EXPERIMENTS #3, 4* 5 t 6t & 7.
*
*
*
#5
9
# of Draws
Total Roots
used in lbs*
133
Average Inulin
8.1
Content in %
Soial Inulin in
10.9
Boots in lbs*
try Inulin
recovered in lbs . 4*31
Recovery in %
Average Inulin
Content in %
39.5
0*24
Extraction %
97.0
bugar in liquor
2.9
Filtrate in %
Volume of
Filtrate in qts* 32.0
loss thru
Hydrolysis
17.0
pH of Liquor
Average CellQ
Temperature C.
5.96
*
*
*
#4
*
*
*
#5
*
*
*
#5
*
*
*
#7
5
5
75
75
210
105
7*6
7.3
7.7
9.85
5.7
5.5
20.8
10.34
2.56
2.69
9.0
3.33
44.9
48.8
0.1
7
43.3
31.8
0.85
0.23
98.6
97.0
91.0
2.9
2.6
2.5
17.0
18.0
17.2
17.0
5.90
Explanation of loss*
5.68
53.0
20.0
10.7
7.70
90 - 95
In th© r©salts of all the experi­
ments on th© diffusion battery, it will be noticed that appre­
ciable losses of inulin are not explained*
A large part of
this loss is due to mechanical imperfections of the battery*
In every ease leaks developed at some point in the system dur-
75
ing the experiment; these and mpchanipal losses due to rapid
handling account for part of the unexplained loss*
Another
important source of error is the transformation of levulose
to glucose during the experiment*
If 1$ of the levulose is
converted to glucose in a solution of levulose, the saccharimeter reading will he reduced by 1.6$.
Xhis is due to the fact
that the reading is not only reduced by l$f from the loss of
levulose, but it is also reduced because the glucose is dextro­
rotatory and its rotation is therefore subtracted from the
levulose reading which is levo-rotatory*
fhe reduction in
reading is 1*6$ rather than the expected 2$ because glucose
has a specific rotation of
52*5° while levulose has a spe­
cific rotation of -90°.
She rate of transformation of levulose to gluoose, with
varying temperatures and under varying pE conditions, has been
investigated at the United States Bureau. *^a
It was shown
that 1$ of the levulose, in a water solution of levulose, is
transformed to glucose in four and one tenth minutes at a
temperature of 100° C* and a pH of 7; at a temperature of 90°
C, and a pH of 7, twelve minutes are required for 1$ trans­
formation; at a pH of 6, twenty-five minutes are required at
100° C*f and seventy-one minutes at a temperature of 90° C*
Sherefore, a large transformation of levulose would occur in
a solution at a temperature of 90° to 100° C. and a pH between
76
6 and 7*
These were the conditions maintained in the oper­
ation of this plant, and since an appreciable quantity of
levulose is formed during extraction, a large part of the
levulose would be in the form of glucose in the liquor fil­
trate of the experiments.
Therefore, the readings obtained
by the Modified Sugar Beet Method, on these filtrates, were
low and the hydrolysis of inulin was larger than that indi­
cated in these data.
The results obtained in determinations of total sugar
in the roots by Quantitative Benedicts reagent were consider­
ably higher than those readings obtained by the Modified Sugar
Beet Method which would indicate that considerable hydrolysis
have
and transformation of the inulin may*already occurred in the
fresh roots.
The levulose present would undergo transformation
throughout the extraction adding to the apparent loss.
Since
it appears that considerable inulin was hydrolyzed before the
diffusion process was started, there was less inulin in the
roots than these results indicated*
A larger per cent of the
available inulin was recovered than is evidenced in these data.
Ho method has been found for determining inulin in the presence
of levulose or levulose in the presence of inulin as they occur
in the roots.
CHAPTEB VI
SUMMARY AMD CONCLUSIONS
fhe purpose of this investigation was to construct and
operate a pilot plant for the extraction of inulin from dahlia
roots*
A review of the literature showed that very little work
had been done in this field*
attempted in this laboratory*
Small scale operations had been
At first, preliminary experi­
ments were performed using 6 ounce bottles coupled as a dif­
fusion battery*
fhese verified previous work and indicated
that extraction by means of a diffusion battery might be a
promising method for obtaining inulin on a large scale*
In order to develop a technique for handling solutions
of the type which would be obtained from a diffusion battery
without large losses, inulin solutions were prepared from
dahlia roots by boiling them in wash boilers and pressing them
to obtain the liquor*
With this liquor the available purifi­
cation equipment was tested*
filtration methods were examined
to determine quantities of decolorizing agents and filter aids
necessary*
Further data on time and pressure required for
filtration of these solutions were gathered*
A pilot plant was built according to a design based
78
upon that of the usual type of diffusion battery*
It was de­
signed to produce about 2 pounds of inulin per hour, using
30 to 60 pounds of roots.
Seven diffusion studies were carried out with this bat­
tery in order to establish, as nearly as possible, the optimum
conditions.
The temperature was kept between 90° and 100° C,
in all oases and variations were made in the time of extrac­
tion and the number of cells.
It was found, by making four determinations with a sys­
tem of twelve cells and about twenty-five minute draws, that
yields of inulin of approximately 40$ could be expected, and
about 97$ would be removed from the roots.
At about twenty
minute intervals and with ten cells, the extraction was equally
thorough, being 98.6$ and with eight cells 97$.
fhe recovery
was 44,9$ with ten cells and 48,8$ with eight cells.
This in­
dicates that eight or ten cells allow for adequate extraction
and that higher recovery, with decreasing number of units in
the diffusion battery and shorter time of draws, can be ex­
plained by the fact that the inulin is exposed to hydrolysis
for a shorter period of time*
However, a system of eight
cells with ten minute draws showed an extraction of 91.3$
and a reoovery of 31.8$.
In all of these determinations the roots were cut quite
79
fin©; the particles averaged about one eighth inch in diameter*
It is to be expected that larger particle size would result in
slower diffusion rates and would consequently require more
cells or slower rate of operation*
This would again lead to
Increased losses through hydrolysis hence smaller particles
Should give more satisfactory yields*
From this research it would appear that the following
conditions lead to the most satisfactory extraction and re­
covery of inulin from dahlia roots by the diffusion method*
1*
The roots should be cut into pieces of one eighth
inch diameter or less*
£•
A battery of eight to twelve cells is adequate*
3*
The time of draw should be about twenty minutes*
4*
The pH of the solution should be maintained as
near 7 as possible*
5*
The temperature of the solution should be between
90° and 100° C.
6*
The liquor obtained should be cooled rapidly in
order to reduce hydrolysis to a minimum*
7*
The inulin should be separated from the mother
liquor by filtration after an interval of thirtysix to forty-eight hours*
The inulin obtained under these conditions can be satisfact­
orily purified by redissolving it in hot water, decolorizing
80
it with 1% decolorizing charcoal, allowing it to stand before
reprecipitating, filtering, and drying#
It has been shown that inulin can be obtained from
dahlia roots in reasonable quantities by extraction in the
diffusion battery#
Yields obtained in the operation of a
pilot plant Indicate the feasibility of converting a beet
sugar plant, in its off season, to extract inulin from dahlia
roots#
With commercial methods of operation and control,
higher yields could be expected#
She conversion of inulin to
levulose syrup or crystalline levulose might be accomplished
by utilizing the sugar end of the factory#
fhese possibilities
are dependent upon the development and production of satis*
factory dahlia roots in large quantities#
Waste
In, to
J e vet\
----- .
I
----- 1
/?o. s :
!/?r- ;/
€nrs,'_ v Wauhcj
o/ c ok - ^ on ConI VQyor ^
r n r
^C
j i'f vor
> C & C03
|ad ded
\
.
\Pressed
J
!P u /b
i
/
D r 4; CO
fSOo/ro
L
D'S/fo/*jt.
Baticr^
Hot
|
L, / C^uah
OeCoion*
-}/*$ C*4»*
C£>n!*dfal
J t# < J 't c i
- i t I u
.
n
end of
factory
In u h n
P a rt a
CarKt
hydnl/..s
CQfke to
dr/er
lt)Ut/n
*—
filte re d
filtrate
btorcd $
36 tirj.
fi/trail|
to t*r-j
/nrnI*
/o^ j
bif ctis
til/artt'oh
Plow
tnation
Sheet
I n u h n f xhr&c f/on
FIGURE 16
f
% ///-
t e n & rd
(y d d c d
wofjrr.
CGffi'C
/IICohrl
/nv/sfl
i
r*
BIBLIOGRAPHY
1.
Bachman, George, John Haldi, Winfrey Wynn, and Charles
Ensor, Journal of Nutrition, Vol. 16, p. 229, 1938.
2.
Bailey, Liberty H., Manual of Cultivated Plants.
3.
Bartel, A. W . t "Purification and Study of Inulin,"
Unpublished Thesis, University of Southern California,
1937.
4.
Black, Le Roy G., "The Commercial Production of Levulose,"
Unpublished Thesis, University of Southern California,
1927.
5.
Bollman, J* L., and P. C. Mann, "Utilization of Various
Carbohydrates by Lepancreatized Animals," American
Journal of Physiology, 107:183-9, Jan. 1934.
6.
Brobst, W. H., "A Study of the Behavior of Inulin in
Solution," Unpublished Thesis, University of Southern
California, 1939.
7. Goudberg, A., Zeitung. Bxp. Path. Ther., 13:310, 1908.
8.
Haworth, W. N . , E. L. Hirst, and E. G. V. Percival,
Chemical Society Journal, Transactions, 141, II,
2684-88, 1932.
9.
Holzman, Josef J., "Studies in the Production of Inulin,"
Unpublished Thesis, University of Southern California,
1938.
10.. Jackson, Richard P., United States Patent #2,007,971,
Process of Making Sugar Products, July 16, 1935.
11.
Jackson, Richard P., C. G. Silsbee, and M, J. Proffitt,
Industrial and Engineering Chemistry, 16:1250-51, 1924.
83
12.
Jackson, Richard P., C. G. Silsbee, and M. J, Proffitt,
United State© Bureau of Standards, Scientific Paper,
Uo. 519, p p . 587-617.
13*
Jackson, Richard P., and R. McDonald, United States
Bureau of Standards, Journal of Re search, Rft 2^S .
14*
Kahn, Allen Ray, and Leroy S. Weatherby, Sugar. Sugar
Publications Co., Los Angeles, p. 37.
15.
McGlumphy, J. E., J. W, Kichinger, with Hixon and
Buchanan, Industrial and Engineering Chemistry.
S3, 1202, i'9#L.
15a. Mathews, Joseph A., and Richard P. Jackson, United States
Bureau of Standards. Bureau of Research. Research Saner.
SFTSTT.------------ -------------------16.
Ohlmeyer, Paul, and Hans Pringsheim, Bar., 66B, 1292*5, 1933.
17.
Peabody, Lawrence, The Dahlia. New York, Orange Judd Pub*
lishing Co., Inc•," 1931.
18*
Pringsheim, Hans, She Chemistry of the Monosaccharides
and of the Polysaccharides. Sew York, W » r a w*Hili, 1932.
19.
Rieger, Wray M., "Commercial Preparation of Levulose from
Dahlia Tubers," Unpublished Thesis, University of
Southern California, 1934.
20.
Shelly, Plorence M., Research in progress, 1940.
21.
Spoehr, H. A., Plant Physiology. 13:207*8, 1938.
22.
Thorpe, Chemical Dictionary. Vol. II, p. 53.
23.
Vivian, R. E., "The Preparation of Levulose," Unpublished
Thesis, University of Southern California, 1922.
Документ
Категория
Без категории
Просмотров
0
Размер файла
4 490 Кб
Теги
sdewsdweddes
1/--страниц
Пожаловаться на содержимое документа