U.S. patent application number 13/996249 was filed with the patent office on 2014-02-27 for method for obtaining a fuel from jatropha seeds that are fich in fat.
This patent application is currently assigned to GEA MECHANICAL EQUIPMENT GMBH. The applicant listed for this patent is Stefan Kirchner, Ines Speiser, Detlef Ullmann. Invention is credited to Stefan Kirchner, Ines Speiser, Detlef Ullmann.
Application Number | 20140057030 13/996249 |
Document ID | / |
Family ID | 45401063 |
Filed Date | 2014-02-27 |
United States Patent
Application |
20140057030 |
Kind Code |
A1 |
Kirchner; Stefan ; et
al. |
February 27, 2014 |
METHOD FOR OBTAINING A FUEL FROM JATROPHA SEEDS THAT ARE FICH IN
FAT
Abstract
A method for obtaining a fuel from jatropha seeds having a fat
content of at least 30% by weight, and simultaneously obtaining a
protein-rich meal.
Inventors: |
Kirchner; Stefan;
(Gutersloh, DE) ; Ullmann; Detlef; (Oelde, DE)
; Speiser; Ines; (Verl, DE) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Kirchner; Stefan
Ullmann; Detlef
Speiser; Ines |
Gutersloh
Oelde
Verl |
|
DE
DE
DE |
|
|
Assignee: |
GEA MECHANICAL EQUIPMENT
GMBH
Oelde
DE
|
Family ID: |
45401063 |
Appl. No.: |
13/996249 |
Filed: |
December 16, 2011 |
PCT Filed: |
December 16, 2011 |
PCT NO: |
PCT/EP11/73109 |
371 Date: |
November 14, 2013 |
Current U.S.
Class: |
426/416 ;
44/307 |
Current CPC
Class: |
C10G 1/047 20130101;
Y02P 30/20 20151101; C11B 1/02 20130101; A23L 33/105 20160801; A23L
33/115 20160801; A23L 11/32 20160801; C11B 1/10 20130101; C10L
1/1802 20130101; C10G 2300/1014 20130101; C11B 3/04 20130101; C10L
1/02 20130101 |
Class at
Publication: |
426/416 ;
44/307 |
International
Class: |
C10L 1/18 20060101
C10L001/18 |
Foreign Application Data
Date |
Code |
Application Number |
Dec 21, 2010 |
DE |
102010055419.7 |
Claims
1. A method for obtaining a fuel from jatropha seeds having a fat
content of at least 30% by weight, and simultaneously obtaining a
protein-rich meal, the method steps comprising: providing jatropha
seeds; removing husk components from the seeds; comminuting the
dehulled seeds; adding one or both of water and acid to the
comminuted seeds to form an oil-containing suspension; separating
crude oil from the suspension wherein the pH value of the
suspension before separation of the crude oil is .ltoreq.3.5; oil
polishing the crude oil; performing neutralization; and drying the
crude oil.
2. The method as claimed in claim 1, further comprising the step of
de-oiling the protein-rich meal and drying of the de-oiled
protein-rich meal.
3. The method as claimed in claim 1, wherein the pH value of added
water is .ltoreq.3.2.
4. The method as claimed in claim 1, wherein the pH value of the
suspension is adjusted with hydrochloric acid before separation of
the crude oil.
5. The method as claimed in claim 1, wherein water and acid are
added, and a dwell time of at least 30 minutes is observed.
6. The method as claimed in claim 1, wherein the separating of the
using a decanter.
7. The method as claimed in claim 1, wherein the oil-containing
suspension has a temperature of from 60 to 80.degree. C. before
separation of the crude oil.
8. The method as claimed in claim 1, wherein the oil-containing
suspension has a temperature of from 80 to 95.degree. C. before
separation of the crude oil.
9. The method as claimed in claim 3, wherein a water-to-product
ratio is in the range of from 1:2 to 2:1.
10. The method as claimed in claim 3, wherein the water content of
the suspension is greater than 35% by weight based on the total
mass of the suspension.
11. The method as claimed in claim 1, further comprising the step
of cleaning of the jatropha seeds occurs prior to the comminuting
step.
12. The method as claimed in claim 11, further comprising the step
of drying of the plant jatropha seeds occurs after the cleaning
step and before the comminuting step.
13. The method as claimed in claim 1, wherein the separating of the
crude oil occurs by repeating a de-oiling from the suspension.
14. The method as claimed in claim 1, wherein after the separating
of the crude oil from the suspension, the suspension has a residual
oil content of less than 4% by weight, based on the total mass of
solids in the suspension.
15. The method as claimed in claim 1, wherein the oil polishing of
the crude oil occurs in a separator.
16. The method as claimed in claim 1, wherein the fat content is at
least 40% by weight.
17. The method as claimed in claim 1, wherein water and acid are
added, and a dwell time of from 30 to 60 minutes is observed.
18. The method as claimed in claim 5, wherein a water-to-product
ratio is in the range of 1:2 to 2:1.
Description
[0001] This application is a national stage of International
Application PCT/EP2011/073109, filed Dec. 16, 2011, and claims
benefit of and priority to German Patent Application No. 10 2010
055 419.7, filed Dec. 21, 2010, the content of which Applications
are incorporated by reference herein.
BACKGROUND AND SUMMARY
[0002] The present invention relates to a method for obtaining a
fuel from jatropha seeds having a fat content of at least 30% by
weight and simultaneously obtaining a protein-rich meal.
[0003] Getting oil from fat-rich seeds is conventional. Methods
currently used are mainly the following: [0004] 1. Pressing plus
hexane estraction [0005] 2. 2-Stage pressing [0006] 3. Cold
pressing
[0007] Fuels are obtained using mainly methods 1 and 2 above, to
maximize oil yield. With neither method is the seed dehulled before
oil recovery, and so the husks remain in the de-oiled meal and thus
adversely affect the nutritional value. Oil quality with these
high-yield methods is relatively low, necessitating costly and
complex refining steps to allow this oil to be used as biofuel.
[0008] EP 0 267 933 A1 discloses a process for obtaining vegetable
oil, in which at least one reagent for reducing the phospholipid
content is added to the oil-containing material. Plants such as,
for example, soybeans or maize are cleaned, dried and dehulled in
preparatory steps. Those plant parts can then be ground. Here, for
example, oil is additionally added. In the extraction of vegetable
oil from these soybeans or maize, hydrochloric acid, among other
things, is also employed. This is used to reduce the phospholipid
content.
[0009] A hydrophobic phospholipid is converted into a hydratable
species. However, because the hydration of phospholipids is
reversible, chelating agents, precipitating agents or the like must
additionally be used in order to stabilize the phospholipids in the
aqueous solution.
[0010] GB 1 179 584 A discloses a process for obtaining fats. The
aqueous extraction of animal fats was therein optimized by
extracting such a fat in a pH range of from 4.1 to 5.8. That pH
value can be achieved, among other things, by addition of acids,
for example hydrochloric acid, sulfuric acid, citric acid or acetic
acid.
[0011] WO 98/53698 A1 and EP 1 905 309 A1 disclose the processing
of rapeseeds, soybeans, maize and sunflower seeds. These are first
ground. Solids are then removed. Finally, washing of the oil phase
is carried out, it being possible to establish a pH value of from 2
to 10 during washing, by addition of Tris-HCl. Formulation to an
emulsion is then carried out. This emulsion is used in the
foodstuffs sector and in the feeds sector, but also in connection
with pharmaceutical and cosmetic products.
[0012] GB 1 402 769 A discloses a process for obtaining oil by an
enzymatic process. Following the enzymatic treatment, which is
carried out at pH values from pH=3 to pH=6, decomposition of the
cell walls of the oil-containing plant product takes place with
liberation of the oil within from 2 to 24 hours.
[0013] EP 2 163 159 A1 discloses the production of oil from
rapeseed.
[0014] After preparation and dehulling of the rapeseed, pressing of
the rapeseed is carried out, in which a press cake and rapeseed oil
are formed. In a process step known as "degumming", the rapeseed
oil is freed of phospholipids, which agglomerate in a reaction
tank. This is followed by a process step of drying and
esterification.
[0015] Biodiesel and crude glycerol are separated by
transesterification in the process.
[0016] In further subsequent steps, proteins and various other
reusable materials can be obtained from the different fractions of
the rapeseed oil or of the rapeseed press cake. The process
described here has only limited suitability for the production of
fuels, because the oil yield from the pressing of dehulled rapeseed
is very low. Owing to the high residual fat content in the de-oiled
press cake, the latter can be utilized to only a limited
degree.
[0017] In the use of fuels from oil plants, oil from jatropha
seeds, also called purging nuts, has been found to be a valuable
alternative, because jatropha oil has a higher cetane number
compared with rapeseed oil, for example, and because the jatropha
plant also grows in nutrient-poor soils.
[0018] Besides oil, proteins are an essential constituent of
jatropha seed. However, the high husk component of the seeds is
problematic at up to 40 percent by weight. If said husk component
is not removed prior to the de-oiling, a protein-rich, meal with a
low oil content is difficult to obtain.
[0019] Today's methods primarily use pressing of the seeds. In
order to achieve a high yield, an appreciable husk content in the
product is essential.
[0020] Embodiments according to the present disclosure provide a
method with which a useful fuel can be obtained to a great extent
from these plant seeds or nuts.
[0021] Such an embodiment or embodiments are discussed below.
[0022] A method, according to the embodiment of the present
disclosure, for obtaining a fuel from fat-containing jatropha
seeds, having a fat content of at least 30% by weight, or, for
example, at least 40% by weight, comprises the following method
steps: [0023] a. removal of husk components; [0024] b. comminution
of plant seeds or nuts; [0025] c. addition of water and/or acid to
the comminuted plant seeds or nuts, to form an oil-containing
suspension; and [0026] d. separation of the crude oil from the
suspension;
[0027] The pH value of the suspension prior to the separation of
crude oil is, for example: pH.ltoreq.3.5.
[0028] The crude oil obtained here is an intermediate in the
production of a fuel. It contains a proportion of residual water
and optionally also smaller solid particles of the plant seed.
[0029] The method just described according to the present
disclosure for obtaining a fuel from fat-containing jatropha seeds
additionally comprises the following method steps: [0030] e) oil
polishing; [0031] f) neutralization; and [0032] g) drying of the
oil.
[0033] Oil polishing is a method of cleaning the oil. The crude oil
is processed further by use of filtration technology or separation
technology and is cleaned of or separated from solids residues and
water. The solids content of the polished crude oil is reduced to
the extent that this oil can be used as a fuel. The residual water
content in the fuel is lowered, for example, to 0.1% by weight or
less by drying.
[0034] The solid phase obtained here is suitable as an intermediate
in the production of a protein-rich meal.
[0035] The oil thus obtained is extremely low in phosphates,
magnesium and calcium and complies with the standard for biofuels,
that is DIN 51605 when polished without further processing. Unlike
pressed oils, complex refining of oils can thus be avoided.
[0036] Water and acid can be fed separately to the suspension or
can be mixed to form a dilute acid before being added to the
suspension. In such a case, the dilute acid already has an
appropriate concentration prior to the addition in order to adjust
the pH value of the suspension to .ltoreq.3.5.
[0037] In the production of fuel from jatropha seeds having a fat
content of at least or more than 30% by weight, or, for example, at
least or more than 40% by weight, it has been found, surprisingly,
that the yield of crude oil increases significantly at a pH value
of .ltoreq.3.5.
[0038] According to embodiments of the present disclosure, fuel,
and if appropriate, also simultaneously a protein-rich meal is/are
obtained from jatropha seeds, that is, the purging nuts of the
jatropha plant.
[0039] Embodiments of the method according to the present
disclosure are discussed herein and in the appended claims.
[0040] Although a significant increase in the yield of fuel is
already to be observed at a pH value of .ltoreq.3.5 as compared
with processing at neutral pH, a particularly advantageous increase
in the yield can, however, be achieved with a suspension having a
pH value .ltoreq.3.2.
[0041] A further increase in the yield of fuel can be achieved by
carrying out the adjustment of the pH value of the suspension
specifically by use of hydrochloric acid. Crude oil can be
liberated from the comminuted plant seeds or nuts as extensively as
possible with a dwell time of at least 30 minutes, or, for example,
from 30 to 60 minutes, after addition of the acid. Because a higher
temperature facilitates the liberation of the crude oil from the
plant seeds or nuts, it is, for example, advantageous for a
temperature of from 60 to 80.degree. C., or, for example, from 80
to 95.degree. C., to be established in the product with the added
water.
[0042] The plant seeds can be cleaned before being comminuted, in
order thus to remove foreign matter adhering to the plants. In
addition, the proportion of solids and foreign substances in the
suspension can be reduced before comminution by prior dehulling and
drying.
[0043] Alternatively or in addition, according to the present
disclosure, the yield of fuel can be increased by carrying out the
comminution of the plant seeds or nuts by use of a mill having a
fine degree of grinding. As a result of the finer degree of
grinding of the plant seeds or nuts, less crude oil is retained
inside the solid components.
[0044] The separation of the crude oil can, within the scope of the
present disclosure, take place from the suspension by repeated
de-oiling. After a first de-oiling, the suspension, with a content
of crude oil of 4 percent or less, is introduced into a second
decanter or returned to the decanter of the first de-oiling for
further de-oiling of the suspension.
[0045] Washing of the crude oil in order to obtain the fuel can,
for example, advantageously be carried out in a centrifuge, or, for
example, in a separator.
[0046] Other aspects of the present disclosure will become apparent
from the following descriptions when considered in conjunction with
the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0047] FIG. 1 shows, schematically, a plant for obtaining a fuel
from jatropha seeds, in accordance with the present disclosure.
[0048] FIG. 1a shows a plant for obtaining a meal, in accordance
with the present disclosure.
[0049] FIG. 2 shows a diagram illustrating the dependence of the
oil content in the de-oiled suspension at different pH values, in
accordance with the present disclosure.
[0050] FIG. 3 shows a diagram illustrating the dependence of the
oil content in the de-oiled suspension with use of different acids,
in accordance with the present disclosure.
[0051] FIG. 4 shows a diagram illustrating the dependence of the
oil content in the de-oiled suspension with different dwell times,
in accordance with the present disclosure.
DETAILED DESCRIPTION
[0052] FIG. 1 shows, schematically, a plant with which, in an
embodiment of the present disclosure, jatropha seeds A are
processed into a crude jatropha oil D which is suitable as a fuel.
The jatropha seeds, or nuts A, having, for example, previously been
cleaned and dehulled.
[0053] In a first step of the treatment, the jatropha seeds A are
first transferred to a mill 1 for comminution. The nuts A are here
broken up and comminuted in a grinder. This grinding process can,
within the scope of the present disclosure, be additionally
facilitated by the supply of further oil.
[0054] The fragments of the comminuted jatropha seeds have a
specific mean grain size, which is specified by the grinder. This
can be carried out in slotted mills, for example.
[0055] Before being comminuted, the jatropha seeds A may, for
example, be dehulled and/or dried. These preparatory steps
facilitate the comminution, or grinding, of the jatropha seeds A.
At the same time, the protein content is increased significantly by
removal of the husk components.
[0056] The embodiments according to the present disclosure include
an important advantage over conventional methods used today,
because the husk fraction can now be used separately, and the
protein content of the de-oiled meal permits its use in various
ways.
[0057] It is within the scope of the present disclosure that more
than 50%, or, for example, more than 80%, or, for example, all of
the husk components are removed.
[0058] After grinding, the comminuted jatropha seeds are
transferred in the form of an oil/solid mixture to a buffer tank 2.
From there, they are transported by way of a first eccentric screw
pump 3 to a mixer or mixing station 4.
[0059] In the mixing station 4, hot water and acid, for example,
hydrochloric acid, HCl, are fed to the ground product and mixed in
such a manner that the suspension has an elevated temperature of
from 60 to 80.degree. C., or, for example, from 80 to 95.degree.
C.
[0060] During this introduction of hot water and acid, a suspension
of solids, oil and water having a pH value of .ltoreq.3.5 is
formed.
[0061] In order to increase the yield of fuel and to obtain a meal
having a low oil content, it is very important that the suspension
formed has a pH value of .ltoreq.3.5.
[0062] The hot water and the acid, for example, concentrated
hydrochloric acid, can also be introduced separately into the
mixing station and form a suspension having a pH value of
.ltoreq.3.5 by intensive stirring. Although this sequence of method
steps may not be preferred, because a locally high concentration of
acid is formed in the suspension, it can be used as an alternative,
in accordance with the present disclosure, to the addition of a
dilute acid to form a suspension.
[0063] In a further embodiment according to the present disclosure,
that may be less preferred, a different acid, for example sulfuric
acid or citric acid, can also be used instead of hydrochloric acid
to adjust the pH value.
[0064] The suspension is then, for example, transferred to a dwell
container 5. It has been found, surprisingly, that the crude oil
yield can, for example, advantageously additionally be increased in
the course of a dwell time. Sedimentation is prevented by gentle
stirring and thus improves the yield. To that end, the dwell
container 5 has a stirrer 6. The dwell time in the dwell container
5 can, for example, be from 30 to 60 minutes. Depending on the
crude material and the acid used, the crude oil yield can even fall
slightly again with a longer dwell time.
[0065] From the dwell container 5, the suspension is transported by
way of a second eccentric screw pump 7 to a decanter 8. This
decanter 8 can, for example, be in the form of a two-phase
separating decanter, where the first phase comprises de-oiled
suspension having a residual oil content of less than 6% by weight,
based on the content of solids in the suspension, and the second
phase comprises crude vegetable oil and, optionally, solid
particles, dissolved in a disperse manner, and residual water.
[0066] Alternatively to a two-phase separating decanter, and within
the scope of the present disclosure, the de-oiling can be carried
out in a 3-phase decanter or in a combination of a clarifying
decanter and a subsequent 3-phase separator.
[0067] The crude vegetable oil is collected in a container, or
buffer tank, 9 and transferred by way of a third eccentric screw
pump 10 and by way of a heat exchanger 11, for example, a plate
heat exchanger, to a centrifuge 12. Disposed between the heat
exchanger 11 and the centrifuge 12 there is a feed for hot water.
This water, for example, advantageously has a temperature of from
60 to 80.degree. C., or, for example, from 80 to 95.degree. C. The
centrifuge 12 may be, for example, in the form of a three-phase
separator, and in the separator both a separation of the water and
oil phase and a clarification of the oil and water phases, removing
solid particles, take place.
[0068] There is discharged from the centrifuge 12 a clear oil phase
in the form of jatropha oil D, which can be processed further by
neutralization and drying to give a product that is suitable for
use as a fuel in combustion engines.
[0069] Furthermore, following the oil polishing, the residual water
content of the oil phase can be lowered to a residual water content
of about 0.05% or less by vacuum drying (not shown. The content of
free fatty acid can be reduced by the neutralization. An important
step in the optimization for obtaining oil from jatropha seeds A is
the optimization of the adjustment of the pH value to
.ltoreq.3.5.
[0070] A further advantageous increase in the yield, in accordance
with the present disclosure, is achieved by the choice of a
suitable acid, the dwell time, the ratio of crude oil and water
and/or acid in the suspension, and the fine adjustment of the pH
value.
[0071] FIG. 2 shows, in a diagram in accordance with the present
disclosure, measured values of the residual oil content in de-oiled
suspensions at different pH values, which suspensions were
discharged from centrifuge 8. A lower residual oil content is
significant for a better yield of jatropha oil and a higher protein
content in the meal. A high residual oil content in the suspension
accordingly reduces the yield of jatropha oil D obtained and lowers
the protein content in the meal.
[0072] The temperature of the suspension was always 90.degree. C.,
the dwell times in the dwell container were always 60 minutes, and
the ratio of water to solid/oil mixture was always 1:1. The tests
at pH=3 were carried out with hydrochloric acid. In the case of the
suspension at pH=5.5, citric acid was used to adjust the pH
value.
[0073] The different residual oil contents of the measured values
depicted in the diagram do not show significant differences in the
residual oil content at pH values between 5.5-6.5 and the residual
oil content of an aqueous extraction in the neutral pH range. At a
pH value of 3.0, however, a significant reduction in the residual
oil content to 3.6% is to be observed. As is clear from the diagram
at FIG. 2, an increase in the yield of jatropha oil is,
surprisingly, noted when the pH value is lowered to below 3.0.
[0074] In addition to the important factor of the pH value, the use
of different acids also leads to varyingly high yields of jatropha
oil D. In the diagram of FIG. 3, citric acid, hydrochloric acid and
sulfuric acid in water were compared with one another under
comparable measuring conditions. The temperatures of the suspension
were always 90.degree. C., the pH value of the solutions was always
3.0, the dwell times in the second buffer tank were always 60
minutes, and the ratio of water to the solid/oil mixture was always
1+1. It is clear from FIG. 3 that extraction using hot water with
the addition of hydrochloric acid is preferred to sulfuric acid and
citric acid, because a particularly large amount of jatropha oil
can, in that case, be extracted from the solids of the
suspension.
[0075] FIG. 4 shows a tendency concerning the dwell times of the
suspension in the dwell container. These tests were carried out
with addition of an aqueous citric acid solution at a pH value of
3.0. It can be seen that a dwell time of 30 minutes is sufficient
to achieve the liberation of the oil phase from the suspension.
[0076] Too long a dwell time, for example, more than 60 minutes, in
the dwell container leads to an increase in the residual oil
content and accordingly to a reduction in the overall yield. The
dependence on the dwell time is, however, also dependent at least
in part on the acid used. The dwell time of from 30 to 60 minutes
has thus been found to be particularly advantageous in the case of
the use of HCl.
[0077] It has been found in tests, in accordance with the present
disclosure, that an additional increase in the yield of fuel can be
achieved if the ratio of water to product after the addition of
water and acid is in the range of from 1:2 to 2:1.
[0078] The water content in the suspension, may, for example, be
greater than 35% by weight, or, for example, be greater than 40% by
weight.
[0079] It has been found, in accordance with the present
disclosure, that a ratio of 1:1 between the solid/oil mixture and
the aqueous phase, that is to say a water content of about 50% in
the suspension, is particularly advantageous.
[0080] Aspects of embodiments of the method according to the
present disclosure are discussed below.
Test 1:
[0081] 800 g of jatropha seed, wild seed from Cape Verde, were
broken manually by use of tongs. The husks were separated off
manually. Breaking was carried out in such a manner that only a
small amount of fines and dust formed.
[0082] The seed, husks and flesh were analyzed. The seed contained
91% dry matter, or, DM, which included 16% protein and 35.7% fat.
The husk fraction of 298 g, or 37.7%, contained 91% DM, which
included 3.3% protein and 0.4% fat.
[0083] The kernel fraction of 502 g, or 62.3%, contained 91% DM,
which included 24.6% proteins and 56.5% fat.
[0084] The two fractions were separated in a visually pure manner,
in each case merely with traces of the other fraction.
[0085] It is apparent in this respect that components of the
jatropha seed that have a relatively low fat content are removed
very effectively by manual dehulling.
Test 2:
[0086] 1013 kg of jatropha seed, wild seed from Cape Verde, were
dehulled by use of a test plant from Probat.
[0087] Breaking was carried out by use of a reflex breaker with a
gap of 3 mm. The breaker was operated at 1300 rpm, the throughput
was 308 kg/h, on average.
[0088] Separation of the husks was carried out in a pilot-scale air
separator. The mean throughput was 296 kg/h.
[0089] The following fractions were obtained: [0090] 1. 507 kg of
kernel fraction (50%) [0091] 2. 494 kg of husk fraction (48.8%)
[0092] 3. 12 kg of dust fraction from the separating cyclone
(1.2%)
[0093] The husk fraction contained 91.4% DM, which includes 7.3%
proteins and 7.8% fat.
[0094] The kernel fraction contained 91.2% DM, which includes 19.8%
proteins and 49.8% fat.
[0095] Both the kernel fraction and the husk fraction visually
still contained components of the other fraction.
[0096] It is apparent in this respect that components of the
jatropha seed that have only a relatively low fat content are also
removed to a large degree by automated dehulling.
Test 3:
[0097] 300 g of dehulled, ground jatropha seed were mixed in a
glass beaker with 450 g of water and stirred for 60 minutes at
90.degree. C. in a water bath. A pH value of 6.2 was
established.
[0098] A further sample was adjusted to a pH value of 3.0 with 90
ml of HCl and likewise stirred for 60 minutes at 90.degree. C. in a
water bath.
[0099] The two samples were then centrifuged for 3 minutes at
4500.times.g in a heatable laboratory centrifuge.
[0100] The solids were then investigated for the residual fat
content.
[0101] While the sample without pH adjustment had a residual fat
content of 12.06%, based on DM, the residual oil content of the
de-oiled sample with pH adjustment was only 3.6.
[0102] This shows the advantage of the pH value adjustment.
Test 4:
[0103] 160 kg of water were heated indirectly to 95.degree. C. in a
heatable stirred vessel. 112 kg of dehulled, ground jatropha seed
were then added. The suspension was adjusted to a pH value of 3.0
with 5.8 kg of concentrated hydrochloric acid, and the suspension
was adjusted to a temperature of 90.degree. C.
[0104] The suspension was stirred gently for 60 minutes in the
vessel.
[0105] The suspension was then separated into an oil phase and a
phase of de-oiled suspension in a CA 220-08-33 2-phase separating
decanter from Westfalia Separator Group GmbH. The bowl speed was
4750 rpm and the differential speed was 18 rpm.
[0106] The feed rate was 300 l/h and was set by use of an
adjustable eccentric screw pump.
[0107] The discharge rate of the oil phase was 63 l/h.
[0108] The de-oiled solid contained 34.8% DM, with 5.4% fat, based
on dry matter DM.
Test 5:
[0109] 180 kg of already de-oiled jatropha suspension with 34.8% DM
and 5.4% fat, from test 4, in the dry matter DM were mixed in a
stirred vessel with 50 liters of water.
[0110] The suspension was stirred gently for 30 minutes and during
this was heated to 90.degree. C. by use of an indirect heat
supply.
[0111] The suspension was then separated into an oil phase and a
phase of de-oiled suspension in a CA 220-08-33 2-phase separating
decanter from Westfalia Separator Group GmbH. The bowl speed was
4750 rpm and the differential speed was 15 rpm.
[0112] The feed rate was 300 l/h and was set by use of an
adjustable eccentric screw pump.
[0113] The discharge rate of the oil phase was 9 l/h.
[0114] The de-oiled solid contained 29.6% DM, with 3.9% fat, based
on dry matter DM.
[0115] A comparison of examples 4 and 5 shows the advantage of
forming the oil-containing suspension, in particular with prior
separation of the husk constituents, as in test 4.
Test 6:
[0116] 36 kg of jatropha oil so obtained were mixed in a stirred
vessel with 1 liter of water and heated to 90.degree. C. with an
indirect heat supply.
[0117] The oil phase was then separated into an oil phase and an
aqueous phase in a BTC 3-03-107 solid bowl centrifuge from
Wesffalia Separator Group GmbH. Solids in the oil were collected in
the bowl of the centrifuge and removed after the test.
[0118] The aqueous phase contained 2.0% DM and had a fat content of
0.05%.
[0119] The oil phase had the following parameters:
[0120] carbon residue: 0.45% (m/m); oxidized ash: <0.005% (m/m);
phosphorus: <0.5 mg/kg; sodium: <0.5 mg/kg; magnesium:
<0.5 mg/kg; calcium: <0.5 mg/kg; potassium: <0.5 mg/kg;
aluminum: <0.5 mg/kg; iron: <0.5 mg/kg.
[0121] The very low phosphate and magnesium content of the oil
phase is very important.
[0122] According to test 4, an oil phase is first obtained. The
yield can be improved by repeated de-oiling. The de-oiling steps of
tests 4, 5 and 6, each of which is optional and in accordance with
the present disclosure, confirm this.
[0123] Although the present disclosure has been described and
illustrated in detail, it is to be clearly understood that this is
done by way of illustration and example only and is not to be taken
by way of limitation. The scope of the present disclosure is to be
limited only by the terms of the appended claims.
* * * * *