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Патент USA US2412635

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Dec. 17, 1946.
P. F. SHARP
2,412,635
PROCESS FOR PRODUCING DRIED IIILK POWDER
Filed Nov. 25, 1943
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INVFN TOR.
Fbul F Sharp
BY
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ATTORNEY
2,412,635
Patented Dec. 17, 1946
UNITED STATES PATENT OFFICE
2,412,635
PROCESS FOR PRODUCING DRIED MILK
POWDER
Paul F. Sharp, Piedmont, CaliL, assignor to
Golden State Company, Ltd., San Francisco,
Calif., a corporation of Delaware
Application November 25, 1943, Serial No. 511,711
11 Claims. (CI. 99-201)
1
This invention relates generally to processes for
the manufacture of dry divided milk products
from liquid lacteal materials, and to the preserva
tion of such products.
In prior processes for producing powdered milk
products such as whole milk it has been found
desirable to reduce the moisture content to a rela
tively low value of the order of from 11/2 to 21/z%.
Where drying equipment of the drum or roller
a 2
stale ?avor because 0! continued oxidation of non
fat solids.
It is an object of the present invention to pro
vide a process for the manufacture of powdered
milk products which will enable production of low
moisture contents without the difiiculties en
countered in prior processes, and with the produc
tion of a high quality material having good keep
ing properties.
type is employed, this is accomplished by ap 10 Another object of the invention is to provide a
process of the above character which will enable
plication of additionalheat and drying time, until
reduction in the moisture content of milk powder
the desired low moisture content is obtained.
to a low value where permanent keeping is as
Where spray drying is employed, additional heated
sured, and without detrimentally exposing the
drying air is introduced into the drying chamber,
product to hot air during the final drying stage.
or the material may be partially dried to powdered
form in a primary drying chamber, and there
after further subjected to hot drying air for a
A further object of the invention is to provide a
process which will reduce the ?nal moisture con
tent of milk solids while at the same time effec
secondary drying to the final moisture content.
tively removing free oxygen.
Such prior drying methods have certain inherent
disadvantages. For example by prolonging heat 20 A further object of the invention is to provide a
process which will treat hot powdered milk im
treatment the capacity 01’ the drying equipment
mediately after a primary drying operation, and
is necessarily reduced, and heat sensitive com
which will quickly cool the material and reduce
ponents of the material may be detrimentally af
its moisture content to a desired low value.
fected. Use of secondary drying increases the
capacity of apparatus employed for the primary 25 A further object of the invention is to provide
a process which will retard development of a stale
drying operation. but the secondary drying itself
?avor due to oxidation of non-fat solids.
is detrimental to the keeping properties or the
Additional objects of the invention will appear
product, particularly in that the hot air to which
from the iollowing description in which the pre
the material is exposed promotes oxidation of the
fat content. Where it is attempted to reduce the 30 ferred embodiment has been set forth in detail in
conjunction with the accompanying drawing.
moisture content to a value of say 1% to 21/270
The present process involves, use of suitable
without secondary drying, the product is dis
equipment for removing moisture from liquid
charged in heated condition. Unless this hot ma
lacteal material to produce an ostensibly dry di
terial is immediately cooled its quality is seriously
vided material, but which however has a moisture
impaired, particularly because complex chemical
content higher than that desired in the ?nal prod
changes in the material which are associated with
uct. A mass of this material while hot is then
deterioration in quality, tend to proceed at an ac
subjected to a relatively high vacuum, whereby
celerated rate at temperatures of the order of
rapid evolution or moisture occurs and the ma
from 150 to 185° F., while in contact with air.
One method which has been employed for cooling 40 terial is cooled to a comparatively low tempera
ture. Simultaneously with evolution of moisture,
the powdered material is to contact the material
free oxygen, such as may be occluded or entrapped
with cool air, but when employing this procedure
with the particles or the powder, is effectively re
it is frequently di?lcult to prevent reabsorption of
moved. By properly controlling the vacuum
moisture, and in addition such cooling can not
be carried out as rapidly as desired. Furthermore
during such cooling the material is subjected to
oxidation ‘by virtue of the oxygen in the cooling
air.
Attempts have been made in the past to inhibit
oxidation of dry milk products, after their manu 60
iacture, by subjecting the same to a vacuum for
removal of free oxygen. It has been found that
such methods as ordinarily practiced have a sub
treatment one can produce a final powdered ma
terial having a desired low moisture content, as for
example of the order of from 1% to 2%% and at
the same time reduce the tree oxygen to less than
1%.
For the ?rst drying operation one can use con
ventionai driers of the roller or spray type, with
or without previous concentration by evaporation.
Powdered material discharged from such driers is
at an elevated temperature, and this hot material
stantial amount 01' free oxygen in the material,
and on storage the material tends to develop a 55 is then progressed to the final treatment, thus
2,412,885
3
4
avoiding reheating or the powder or retention oi’
um condenser 22. This condenser can consist for
the same at an elevated temperature for detri
example of a condensing chamber 34 having cool
ing coils 38 in its upper portion, and having its
lower end connected to the condensate pipe 21.
mentally long periods of time.
The drawing diagrammatically represents a
particular procedure and equipment which can
Pipe 30 represents a connection to a suitable
be used for practicing the invention. In this in
evacuating pump. Suitable cooling liquid is cir
stance whole milk which may be clari?ed‘ as by
culated through the coils 38. Pipe 21 can be an
centrifuging, is passed through a heater l0 where
extended barometric leg.
it is rapidly heated to an elevated temperature of
The inlet pipe 26 to chamber 24 is shown pro
the order of from 130 to 140° F'., after which it is 10 vided with a three way valve 4| having one op
?ashed or permitted to expand in the evacuated
erating position in which powder may enter
chamber 24 through pipe 26, a second position in
chamber II, which is maintained at a suitable
vacuum such as 28 inches of mercury. This
which pipe 26 is closed, and a third position in
serves the purpose of e?ectively removing in
which the chamber is placed in communication
corporated air and has been found desirable in 15 with a venting pipe 42. It is preferable to have
preserving the vitamin C content of the material.
this pipe connected to a source of inert gas, such
as nitrogen.
The deaerated material is then passed to the
The valves 3| and 4| as well as the bearings
evaporating equipment l2 which can be of the
fo'r the agitator shaft 25, should be designed to
vacuum type, and where the moisture content is
reduced to a desired value, as for example from 40 20 prevent admission of air. For example as
diagrammatically indicated the valves SI and 22
to 55% solids. Either before, during or imme
diately after this evaporating operation, it is de
can be jacketed where their operating members
extend from the bodies of the valves, and these
sirable to pass the material through a heater l3
jackets can then be connected to a source 01'
where it is rapidly heated to an elevated tempera
ture of from 180 to 230° F. This treatment serves 25 vacuum by pipes 42 and 44. Similarly the gland
21 about shaft 24 can be provided with an inner
to produce substances in the milk which tend to
compartment surrounding the shaft and con—
prevent oxidation of fats and deterioration of
nected to a source of vacuum by pipe 45. Cham
certain vitamin values, particularly vitamin C.
ber 23, pipe 32 and condensing chamber 24 are
The milk concentrate is then subjected to dry
ing or desiccation to convert the same to the form 30 all shown provided with external heat insula
tion. Also the walls of chamber 22 are prefer
of a powder. Apparatus I4 shown in the drawing
ably heated by suitable means such as the pipes
for this purpose is a spray drier, which for ex
45 through which hot water can be circulated.
ample may be of the Gray-Jensen type. Heated
Operation or the process and apparatus de
drying air is introduced through the inlet con
scribed above can be reviewed as follows: The
duit I8 and air ladened with moisture is exhausted
whole milk after being heated at l0 and deaerated
through conduit I5. The spray drier is operated
at II is concentrated at l2. The concentrate
in such a manner that the resulting powdered
after being'heated at It is applied to the atomiz
material removed through outlet conduit l5, has
ing nozzle of the spray drier l4. Within the
a moisture content considerably greater than that
spray drier the material is reduced to a moisture
desired in the ?nal product, as for example of the
content of say 3V2%. and as delivered to the
order of from 3% to 5%. Such operation involves
storage tank 2| it is at a temperature of the order
proper control with respect to the rate 01' atomiza
of from 170 to 180° F. Storage within this cham
tion of the concentrate, and the ?ow rate and
ber is for a relatively short interval and makes
temperature 01' the incoming drying gas. By way
possible use or evacuating apparatus 22 of the
of example, in one speci?c instance the drier pro
batch type. In the event evacuating apparatus
duced powdered whole milk having a moisture
of the continuous type is employed, such storage
content between 31/2 to 5% when adjusted to pro
can be minimized or omitted in entirety. Before
vide air entrance through the conduit ii at a
the powdered material has had an opportunity
temperature of from 280 to 300° F. Under such
conditions of operation the powdered material 50 to cool to an appreciable extent, it is introduced
into the chamber 24, after which valve 4| is closed
discharged through conduit I1 was at a tempera
and valve 45 is opened to evacuate the chamber
ture of the order of from 175 to 185° F.
and thereby subject the powdered material to a
The hot powdered material removed through
relatively low pressure of the order of 0.25 to 0.10
conduit I1 is shown being delivered by blower iii
inch of mercury. The mass of powdered mate
to the centrifugal separator l9, where it is sepa
rial is kept under continual agitation by rotation
rated out from the drying gas. It is then shown
of rod 25. Application oi’ a vacuum of this order
passing to the receiver or storage hopper 2|.
causes rapid evolution oi’ moisture because the
From hopper 2| the material is shown being de
reduced pressure is well below the vapor pressure
livered through conduit 22 to a special vacuum
treatment apparatus 23.
60 of moisture contained within the material. Rapid
evolution of moisture is accompanied by loss of
The vacuum treatment apparatus 23 has been
heat and cooling of the material to a relatively
shown including a chamber 24, which has its inlet
low temperature.
pipe 26 connected to the conduit 22 from tank 2 I.
In addition to reducing the moisture content
Within the chamber 24 there is a suitable me
and cooling the material, the present process is
chanical agitating means, consisting for example
highly e?ectlve in removing free oxygen which
of a rotatable rod 28 extending into the chamber
may be occluded or entrapped in the particles
through the bearing and sealing gland 21. Rod
of material. Oxygen and other gases from the
26 is shown provided with radially extending
air are inevitably present in the material by
?ights 21, and the bottom stirring ?ights 28. The
powdered materia1 can be discharged through the 70 virtue of exposure of the material to heated air
during spray drying or other drying operation
lower end of chamber 24 through outlet pipe 29,
utilized for initially converting the material to
which is provided with a suitable shut-oil’ valve
divided solid form. with the present process
The upper part of chamber 24 is connected by
evolution oi‘ moisture by subjecting the hot mate
pipe 32 to a source of vacuum, through the vac“ 75 rial to a high vacuum greatly facilitates rapid
' auaoss
removal of free oxygen, and the free oxygen
content can be reduced to a value of the order of
1% or less in a comparatively short time, such as
one hour or less. On the other hand when milk
powder containing from 1% to 2%% moisture
and at ordinary atmospheric temperature is sub
Jected to a high vacuum, the free oxygen is re
moved with greatest difliculty and it is necessary
to maintain a mass of material under the high
vacuum for a prolonged period such as 24 hours
or longer and to employ one or more dilutions
with an inert gas like nitrogen, in order to ap
6
the steps of spraying the material into contact
with hot air in a controlled drying chamber, re
moving the relatively high humidity gas from the
chamber, removing powdered product from the
bottom of the chamber at an elevated tempera
ture of the order of from 170° F. to 185° F. and
having a moisture content of the order of from
3.5 to 5% and before any appreciable drop in
temperature has occurred, subjecting the powder
to a relatively low pressure of the order of from
0.25 to 0.10 inch of mercury for the relatively
short period of time su?icient to evaporate the
moisture content of the powder down to a value
of the order of from 1.0 to 2.0%, said evaporation
After a comparatively short interval of time, 15 effecting substantial cooling of the powder.
2. In a process for the manufacture of dry
‘during which application of vacuum is main
powdered milk products from liquid lacteal mate
tained, the moisture content of the material is
rial, the steps comprising spraying a milk con
reduced to a value of from say 1V: to 2%, the
centrate into contact with hot air in a controlled
temperature of the material is reduced to say
110“ F‘. and the free oxygen reduced to about 20 drying chamber, removing a portion of the rela
tively humid air from the top of the chamber,
0.8%. During the vacuum treatment vapor
removing the hot powdered product having a
evolved passes through pipe 32 to the condenser
moisture content of the order of from 3.5 to 5.0%
33, where vapor is condensed with water and
and the remaining portion of said humid air from
withdrawn through the condensate pipe 01.
the bottom of the chamber, separating the pow
At the end of the vacuum treatment valve 45
der from said air and before appreciable drop
is closed and valve 41 is turned to break the
in temperature has occurred, subjecting the pow
vacuum in chamber 24 by venting in gas through
proach the effectiveness of oxygen removal
accomplished in the present process.
pipe 42. Assuming that this is an inert gas like
nitrogen, which is preferred practice, the particles
der to a relatively low pressure of the order of
from 0.25 to 0.10 inch of mercury for the rela
of the powdered material are enveloped in the 30 tively short period of time sufficient to evaporate
the moisture content of the powder down to a
inert gas and are removed together with this
value of the order of from 1.0 to 2.0%. said evap
gas when withdrawn through pipe 20. It is de
oration effecting substantial cooling of the pow
sirable to have this pipe connect directly with
der.
equipment whereby the material is introduced
3. In a process for the manufacture of dry
into sealed containers for distribution to the .
powdered milk products from liquid lacteal ma
trade, or if desired the material can be introduced
terial, the steps comprising spraying a milk con
into closed storage chambers, before being placed
centrate into contact with hot air in a controlled
in sealed containers.
drying chamber, removing the relatively humid
To review the advantages of the present
air and the hot powdered product having a mois
process, it is possible to operate the spray drier
ture content of the order of from 3.5 to 5.0% from
ll or other drying apparatus employed at rela
the bottom of the chamber, separating the pow.
tively high capacity, with effective and emcient
der from the air and before any appreciable drop
reduction in moisture content to a relatively low
in temperature has occurred, subjecting the pow
value in the final stage of the process. Prolonged
der to a relatively low pressure of the order of
exposure to elevated temperatures in the primary
from 0.25 to 0.10 inch of mercury for the relatively
drying stages is completely avoided, and thus
short period of time sufficient to evaporate the
the material leaves these stages in unimpaired
moisture content of the powder down to a value
condition. Long storage of the powdered mate
of the order of from 1.0 to 2.0%, said evaporation
rial at elevated temperatures is avoided and the
effecting substantial cooling of the powder.
residual sensible heat of the particles after pre
4. In a process for the manufacture of dry pow
liminary drying is utilized in the ?nal drying
dered products from liquid lacteal material, the
operation. In the final drying operation there is
steps comprising spraying the material into con
no impairment to the quality or keeping proper
tact with hot air in a controlled drying chamber,
ties of the milk, particularly as contrasted with
the impairment taking place in prior conven- I removing a portion of relatively humid air from
the chamber at a point removed from the point
tional secondary drying.
of powder discharge, removing the hot powdered
The final product is not only of the desired
product having a moisture content of the order
moisture content but in addition it is associated
of from 3.5 to 5.0 per cent and the remaining por
with a relatively low percentage of free oxygen,
tion of said humid air from the chamber, sepa
that is of the order of 1% or less. It has been
rating the powder from said air and before 8.?
found that such a low percentage of free oxygen
preciable drop in temperature has occurred, sub
makes possible retardation in the oxidation of
jectlng the powder to a relatively low pressure of
non-fat milk solids such as causes development
the order of from 2 to 0.10 inches of mercury for
of a stale ?avor, as well as to inhibit oxidation of
fats. Thus the present product is more effectively - the relatively short period of time sufficient to
evaporate the moisture content of the powder
preserved against development of undesirable ?a
down to a value of the order of from 1.0 to 2.0
vors and in general has a longer keeping period.
Der cent, said evaporation effecting substantial
With respect to retarding oxidation of non-fat
cooling of the powder.
solids the invention is applicable to the produc
5. In a process for the manufacture of dry
tion of dry skim milk, as well as to milk products
like whole milk which have a substantial fat con
tent.
I claim:
1. In a process for the manufacture of pow
dered milk products from liquid lacteal material,
powdered products from liquid lacteal material,
the steps comprising spraying the material into
contact with hot air in a controlled drying cham
ber, removing a portion of relatively humid air
from the chamber at a point removed from the
7
2,419,885
point of powder discharge, removing the hot pow
dered product having a moisture content of the
order or from 3.5 to 5.0 per cent and the remain
8
product having a predetermined moisture con
tent several per cent higher than desired in
the ?nal product from the system, and before
ing portion of said humid air from the chamber,
appreciable drop in temperature has occurred,
separating the powder from said air and before I subjecting the hot material to a relatively low
appreciable drop in temperature has occurred,
sub-atmospheric pressure for the relatively short
subjecting the powder to a relatively low pressure
of the order of from 3 to 0.10 inches of mercury
for the relatively short period of time sumcient to
evaporate the moisture content of the powder 10
down to a value of the order of from 1.0 to 2.0 per
period of time sumcient to evaporate the mois
ture content of the powder down to a value of
the order of from 1 to 2%, said evaporation ef
fecting substantial cooling of the powder.
9. In a process for the manufacture of dry
cent, said evaporation e?ecting substantial 0001-
products from liquid lacteal materials, the steps
ing of the powder.
comprising spraying the material into a con
6. In a process for the manufacture of dry
trolled drying chamber to form a pulverulent
milk products from liquid lacteal materials, the i5 material of a predetermined moisture content
steps of spraying the material into contact with
higher than desired in the ?nal product, remov
hot gas in a controlled drying chamber, removing said pulverulent material from said drying
mg the major portion of the relatively humid gas
chamber while hot and conveying it to the cooling
from the top of said chamber, removing a minor
chamber under conditions to minimize loss of
portion of the humid gas together with the hot 20 heat, and then subjecting a mass of the pul
pulverulent product of predetermined moisture
verulent material to sub-atmospheric pressure
content higher than desired in the ?nal product
substantially below the vapor pressure of the
irom the bottom of said chamber, separating the
moisture contained in the hot pulverulent ma
pulverulent material from the humid gas with
terial whereby a portion of the moisture content
which it is associated as it leaves the drying at is ?ashed oil’ and the material cooled.
chamber and before too appreciable a drop in
10. In a process for the manufacture of pow
the temperature 01' said material has occurred,
dered milk products wherein the liquid lacteal
subjecting the pulverulent material to the action
material is sprayed into contact with hot gas
of a high vacuum for the relatively short period
in a controlled drying chamber to produce a
of time to evaporate a su?lcient portion of the to product which is removable from said drying
moisture from the hot powder to eil'ect subchamber as a hot powder, the steps comprising
stantialcooling.
removing powdered products of predetermined
7. In a process for the manufacture of dry milk
moisture content higher than desired in the ?nal
products from liquid lacteal materials, the steps
product from said chamber at an elevated tem
of spraying a milk concentrate into contact with as perature and subjecting the hot powder to sub
hot gas in a controlled drying chamber, removing
atmospheric pressure substantially below the
the relatively humid gas from the upper region
vapor pressure of the moisture contained in the
of the chamber, removing the hot pulverulent
hot powder whereby a portion of the moisture
product of predetermined moisture content
content is ?ashed 011' and the powder cooled.
higher than desired in the ?nal product from, 40
11. In a process for the manufacture of
the bottom of said chamber, subjecting the hot
powdered milk products from liquid lacteai
product as it leaves the drying chamber to submaterial, the steps of effecting primary drying
atmospheric pressure substantially below the
of the lacteal material by heat transfer to the
vapor pressure or the moisture contained in the
same to form a hot divided solid material having
hot pulverulent product whereby a portion of 45 a moisture content substantially in excess of the
the moisture content is ?ashed oil and the pul-
moisture content of the ?nal product, and then
verulent product cooled.
transferring the materia1 without substantial
8. In a process for the manufacture of dry
loss of sensible heat to a zone of secondary treat
powdered products from liquid lacteal material,
ment in which the material is subjected to a
the steps comprising spraying the material into 50 vacuum below the vapor pressure of moisture
contact with hot air in a
system, removing humid air
point in the system removed
powder discharge. removing
controlled drying
from at least one
from the point of
the hot powdered
remaining in the material to thereby rapidly
reduce the moisture content and cool the same.
PAUL F‘. SHARP.
Disclaimer
2,412,635.—Paul F. Sharp, Piedmont, Calif. Pnocnss roa Pnonucmo Damn MILK
POWDER. Patent dated Dec. 17, 1946. Disclaimer ?led July 14, 1948, by
the assignee, Golden State Company, Ltd.
Hereby disclaims claims 9, 10, and 11 of said patent.
[Official Gazette August 17, 1948.]
7
2,419,885
point of powder discharge, removing the hot pow
dered product having a moisture content of the
order or from 3.5 to 5.0 per cent and the remain
8
product having a predetermined moisture con
tent several per cent higher than desired in
the ?nal product from the system, and before
ing portion of said humid air from the chamber,
appreciable drop in temperature has occurred,
separating the powder from said air and before I subjecting the hot material to a relatively low
appreciable drop in temperature has occurred,
sub-atmospheric pressure for the relatively short
subjecting the powder to a relatively low pressure
of the order of from 3 to 0.10 inches of mercury
for the relatively short period of time sumcient to
evaporate the moisture content of the powder 10
down to a value of the order of from 1.0 to 2.0 per
period of time sumcient to evaporate the mois
ture content of the powder down to a value of
the order of from 1 to 2%, said evaporation ef
fecting substantial cooling of the powder.
9. In a process for the manufacture of dry
cent, said evaporation e?ecting substantial 0001-
products from liquid lacteal materials, the steps
ing of the powder.
comprising spraying the material into a con
6. In a process for the manufacture of dry
trolled drying chamber to form a pulverulent
milk products from liquid lacteal materials, the i5 material of a predetermined moisture content
steps of spraying the material into contact with
higher than desired in the ?nal product, remov
hot gas in a controlled drying chamber, removing said pulverulent material from said drying
mg the major portion of the relatively humid gas
chamber while hot and conveying it to the cooling
from the top of said chamber, removing a minor
chamber under conditions to minimize loss of
portion of the humid gas together with the hot 20 heat, and then subjecting a mass of the pul
pulverulent product of predetermined moisture
verulent material to sub-atmospheric pressure
content higher than desired in the ?nal product
substantially below the vapor pressure of the
irom the bottom of said chamber, separating the
moisture contained in the hot pulverulent ma
pulverulent material from the humid gas with
terial whereby a portion of the moisture content
which it is associated as it leaves the drying at is ?ashed oil’ and the material cooled.
chamber and before too appreciable a drop in
10. In a process for the manufacture of pow
the temperature 01' said material has occurred,
dered milk products wherein the liquid lacteal
subjecting the pulverulent material to the action
material is sprayed into contact with hot gas
of a high vacuum for the relatively short period
in a controlled drying chamber to produce a
of time to evaporate a su?lcient portion of the to product which is removable from said drying
moisture from the hot powder to eil'ect subchamber as a hot powder, the steps comprising
stantialcooling.
removing powdered products of predetermined
7. In a process for the manufacture of dry milk
moisture content higher than desired in the ?nal
products from liquid lacteal materials, the steps
product from said chamber at an elevated tem
of spraying a milk concentrate into contact with as perature and subjecting the hot powder to sub
hot gas in a controlled drying chamber, removing
atmospheric pressure substantially below the
the relatively humid gas from the upper region
vapor pressure of the moisture contained in the
of the chamber, removing the hot pulverulent
hot powder whereby a portion of the moisture
product of predetermined moisture content
content is ?ashed 011' and the powder cooled.
higher than desired in the ?nal product from, 40
11. In a process for the manufacture of
the bottom of said chamber, subjecting the hot
powdered milk products from liquid lacteai
product as it leaves the drying chamber to submaterial, the steps of effecting primary drying
atmospheric pressure substantially below the
of the lacteal material by heat transfer to the
vapor pressure or the moisture contained in the
same to form a hot divided solid material having
hot pulverulent product whereby a portion of 45 a moisture content substantially in excess of the
the moisture content is ?ashed oil and the pul-
moisture content of the ?nal product, and then
verulent product cooled.
transferring the materia1 without substantial
8. In a process for the manufacture of dry
loss of sensible heat to a zone of secondary treat
powdered products from liquid lacteal material,
ment in which the material is subjected to a
the steps comprising spraying the material into 50 vacuum below the vapor pressure of moisture
contact with hot air in a
system, removing humid air
point in the system removed
powder discharge. removing
controlled drying
from at least one
from the point of
the hot powdered
remaining in the material to thereby rapidly
reduce the moisture content and cool the same.
PAUL F‘. SHARP.
Disclaimer
2,412,635.—Paul F. Sharp, Piedmont, Calif. Pnocnss roa Pnonucmo Damn MILK
POWDER. Patent dated Dec. 17, 1946. Disclaimer ?led July 14, 1948, by
the assignee, Golden State Company, Ltd.
Hereby disclaims claims 9, 10, and 11 of said patent.
[Official Gazette August 17, 1948.]
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