Improvements in the Separation of Fats from Emulsions.
Year: 1890

page_text: COMPLETE SPECIFICATION.
Improvements in the Separation of Fats from Emulsions.
I, CARL DIDRIK HELLSTROM, Engineer of Stockholm Sweden do hereby declare
the nature of this Invention and in what manner the same is to be performed to be
particularly described and ascertained in and by the following statement:—
;
In an emulsion the particles of fat are in the form of spheres of very different sizes
for example in milk, the largest are of about 20 times greater volume than the smallest.
Each sphere of fat is surrounded with a zone of the surrounding liquid. The zono
lessens the flotation of the spheres of fat in proportion to the size of the latter, so that
the smaller spheres no longer possess any flotation; these cannot be separated by
centrifugal action alone, except when the larger spheres draw them in a manner with
them. The path of the larger spheres through the mass under the influence of
centrifugal action will be an unbroken line. When however the mass also receives a
motion parallel to the axis, the larger spheres which possess flotation will on account of
If the axial
their small density receive a relative motion in an axial direction.
motion continually changes its direction the larger spheres will travel in a zig zag
course about the line, which in the absence of axial movement would have been
the path. The larger spheres so travelling will continually collide with the smaller
spheres of fat, which on account of the surrounding zones do not take part in the
relative motion. The separation of the fat is rendered more complete by this method.
As the axial movement in the mass gives rise to pressure, the particles will coalesce and
the enlargement of the at first small particles of fat takes place fairly quickly throughout
the mass.
On the surface this enlargement of the spheres of fat is hastened by the
movements originated by the axial motion. In centrifugal action the surface places
itself normally to the resultant of the centrifugal force and gravitation, if there be
also axial motions the surface tends to place itself normally to the resultant of all
three; as however the axial motion is variable both as regards amount and direction,
the particles on the surface have a wavy motion. This takes place quite sym-
metrically round the axis, so that a section which is placed perpendicular to the axis
will be alternately extended and compressed and by this means the particles of fat will
be made to unite. By each union of two spheres a portion of the liquid which
envelopes the spheres will be liberated; the fat therefore is more thoroughly freed
from liquid than by centrifugal action alone.
When the temperature of the emulsion is such, that the fat is cool, the transition to
a firmer state of aggregation is hastened by the repeated variations of pressure ;
if for example milk is treated at a temperature under 23° C. in this way, butter is
produced.
With continuous inflow and outflow the process is made continuous.
The axial movements may be produced by various arrangements. The annexed
drawing gives an example. A is a shaft in the bearings C C by means of the pulley D
it is set in rotation. F is a connecting rod, which at one end embraces the crank B
on the shaft A, and the other end by means of the pins a connects with the sleeve G
on the axle H of the centrifugal machine. b and c are collars on the axle of the
centrifugal machine, by means of which the axle receives movement from the connecting
rod. The axle H of the centrifugal machine is set in rotation by means of the
pulley J. d is a pin in the boss of the pulley J, which pin enters a slot e in the axis
of the centrifugal machine. Thus the axle H can rotate independently of the axial
movement. KK are bearings for the axis of the centrifugal machine. Lis the basket
of the centrifugal machine is the pipe admitting the emulsion, g is the outlet for
the separated fat. The liquid passes away at the periphery by the pipe h and the
hole i

page_text: Having now particularly described and ascertained the nature of my said Inven-
tion and in what manner the same is to be performed I declare that what I
claim is:
1. The process substantially as described for the separation of fat from emulsions,
wherein the. emulsion is exposed to the simultaneous influence of rotary motion and of
motion either quite or nearly parallel with the axis of rotary movement.
2. Apparatus substantially as described and illustrated by the annexed drawings.
Dated this 11th day of June 1890.
CARPMAEL & Co.,
Agents for the Applicant.