An Improved Process and Apparatus for the Concentration and Crystallization of Saccharine and other Crystallizable Liquids.
Year: 1899

page_text: Date of Application, 27th Nov., 1899
Complete Specification Left, 24th Aug., 1900-Accepted, 24th Nov., 1900
An Improved Process and Apparatus for the Concentration and
Crystallization of Saccharine and other Crystallizable Liquids.
JOHN MCNEIL and CHARLES MCNEIL, Engineers, both of Colonial Iron Works,
Govan, Lanarkshire, do hereby declare the nature of this invention to be as
follows:
: -
To carry out in a practically continuous manner the concentration, crystalliza-
tion and discharge of a granulated mass of saccharine or other crystallizable liquids.
The process of crystallization is dependent on the bringing up of the density of
a solution to the hot saturated state corresponding to the temperature existing
in the vessel; the supersaturation of this solution in order to start crystallization
or the formation of grain; the addition of the required amount of syrup, or thick
juice, or liquor to increase the size of the minute or newly formed crystals; the
application of heat to evaporate the water set free by the formation of crystals
and thus to keep the solution saturated.
This series of operations is usually accomplished in a single vacuum pan, but
as its action is intermittent and at times the greater part of the heating surface
is out of action, it follows that a very large amount of surface is required to do
the work. To overcome this difficulty and to carry on the above series of opera-
tions in a practically continuous manner the vacuum pan has been, according to
this invention, subdivided into a series, or battery, of vessels, the number of
which is determined by the quantity and kind of liquor to be treated and the
density at which the finished mass is to be discharged.
Each vessel is provided with a suitable heating surface intended to utilise
exhaust or low pressure steam, and may be provided with a mechanical screwing
arrangement to assist the concentration and discharge.
The first vessel of the series works intermittently by drawing in charge after
charge of the syrup or liquid to be treated, bringing each charge up to the hot
saturated state, and then forming the grain, technically termed "seed," in the
usual way, and dropping the same into a vessel placed underneath it termed the
"seed receiver." The seed receiver is provided with a steam jacket to keep the
seed at a constant and uniform temperature and is provided with a stirrer to keep
the charge in motion in order to reduce the risk of false grain being formed.
The seed is drawn up continuously into the second vessel of the series; at the
same time a continuous supply of syrup or thick juice is introduced, by which
the seed, or grain, is nourished and increased in size. The mass then passes
continuously into the third vessel. The third vessel is also fed continuously with a
regulated allowance of syrup to still further nourish and increase the size of the
seed or grain on its way to the last vessel. In the last vessel no syrup need be added
as it is intended merely to finish the thickening of the mass up to a density, in
the case of saccharine liquids, of about 93° Brix. The discharge from this vessel
is also continuous and is effected by a mechanical screwing arrangement which
propels the charge entering from the preceding vessel towards the outlet end

page_text: where it escapes by a suitable orifice on the vessel and a torricellian tube. This
tube may lead into a tank and be emptied by means of a regulating valve and
pump or by any other suitable means.
In this way the seed originally formed in No. 1 cell is continually passed
through all the cells of the battery, being gradually increased in size in each cell
by the addition of thick juice or nourishing liquor till it is crystallized up to the
required degree, and discharged continuously from the last vessel. The function
of the first vessel is to prepare the seed for use in the battery and keep the seed
receiver filled.
The functions of the vessels in the battery following the seed receiving vessel
is to increase the size of the crystals and concentrate the mass up to the required
density.
If it be desired to add molasses or syrup of a lower purity, this can be done in
the case of large apparatus by increasing the number of the vessels and dis-
charging continuously, or in the case of small apparatus the continuous discharge
might be dispensed with and the vessel preceding the last allowed to fill up
whilst the last is thickening up with molasses.
Doted his Tonter fifth law of Navaho 1800
JOHN MCNEIL,
CHARLES MCNEIL.
An Improved Process and Apparatus for the Concentration and
Crystallization of Saccharine and other Crystallizable Liquids.
JOHN MCNEIL and CHARLES MCNEIL, Engineers, both of Colonial Iron Works,
Govan, Lanarkshire, 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: —
To carry out in a practically continuous manner the concentration, crystalliza-
tion and discharge of a granulated mass of saccharine or other crystallizable liquids.
The process of crystallization is dependent on the bringing up of the density of
the solution to the saturated state corresponding to the temperature existing
in the vessel the super-saturation of this solution in order to start crystallization
or the formation of grain; the addition of the required amount of syrup, or thick
juice, or liquor to increase the size of the minute newly formed crystals; and the
application of heat to evaporate the water set free by the formation of crystals
and thus keep the solution saturated.
This series of operations is usually accomplished in a single vacuum pan, but
as its action is intermittent, and at times the greater part of the heating surface
is out of action, it follows that a very large amount of surface is required to do
the work. To overcome this difficulty and to carry on the above series of opera-
tions in a practically continuous manner the vacuum pan has been, according to
this invention, subdivided into a series, or battery, of vessels, all of which are
to work under vacuum, the number of which vessels is determined by the quantity
and kind of liquor to be treated and the density at which the finished mass is
to be discharged. Each of the vessels is provided with a suitable heating surface
intended to utilize exhaust or low pressure steam, and may be provided with a
mechanical screwing or mixing arrangement to assist in the concentration and
discharge of the material.
With these objects in view our invention consists in the improved construction
and novel arrangement of the apparatus, and in the improved process of concen-
tration and crystallization of liquids as will be hereinafter more fully set forth.

page_text: In the accompanying drawings in which the same reference numerals indicate
corresponding parts of the apparatus in each of the views in which they occur:
Figure 1 is an illustration of so much of a plant as is necessary to practice
our invention, the pans being shewn in vertical section.
Figure 2 is a similar view of a modification of the same.
Referring more particularly to the drawings, 1, 2 and 3 indicate vessels which
are connected with a suitable exhaust pipe 4, and each provided with the usual
steam coil or heater 5, and an inlet or feed pipe 6. A vessel or tank 7 which we
shall call a seed receiver, is placed under the vessels 1 and 2 and connected with
the latter by means of a pipe 8. It is provided with a steam jacket as indicated
at 9 and with a screw or stirrer indicated by dotted lines 10. A spout or trough
communicates with one end of the vessel 7 and extends under the lower end of
vessel 1 so as to receive the material therefrom as it is discharged through the
outlet 11, and conduct it into the vessel 7.
Adjacent to the vessel 3 and connected therewith by a pipe 12 is a vessel 13
which is provided with a steam jacket 14 and a screw 15 which extends from end
to end. A torricellian discharge tube 16 is connected with one end of the
vessel 13 and with a tank 17. Pipe 18 is the outlet for the finished material to
pass from vessel 13 into tank 17. Tank 17 must be placed so much below the
level of vessel 13 that the column of semi fluid material will counterbalance the
atmospheric pressure on its surface in tank 17. The top of the vessel 13 is con-
nected with the exhaust pipe 4 by means of a pipe 19 in the same manner as the
vessels 1, 2, and 3.
Instead of providing the apparatus with a continuous discharge, as above
described, the vessel 13 anil tank 17 may be replaced with two vessels, 20 and 21,
each of which is connected with the exhaust pipe 4 and provided with the steam
coil 22, as shewn in Figure 2. In this construction, the two vessels work inter-
mittently, the one thickening up with molasses while the other one is being
charged.
In operation the first vessel, 1, of either series, works intermittently by draw-
ing in charge after charge of the syrup or liquid to be treated, bringing each
charge up to the hot saturated state, and then forming the grain, technically
termed "seed," in the usual way, and dropping the same into the vessel 7, placed
underneath it. The seed receiver is kept at a constant and uniform temperature
by a steam jacket around it and its charge is kept in motion by the stirrer 10
to reduce the risk of false grain being formed.
The seed is drawn up continuously from the receiver 7 into the second vessel, 2,
of the series; at the same time a continuous supply of syrup or thick juice is
introduced, by which the seed or grain is nourished and increased in size. The
mass then passes continuously into the third vessel 3. The third vessel is also
fed continuously with a regulated supply of syrup to still further nourish and
increase the size of the seed or grain on its way to the last vessel.
In the last vessel no syrup need be added as it is intended merely for finishing
the thickening of the mass up to a density, in the case of saccharine liquids, of
about 93° Brix. The discharge from this vessel is also continuous and is effected
by a mechanical arrangement, as the screw 15, which propels the charge enter-
ing from the preceding vessel towards the outlet where it escapes by a suitable
orifice in the side of the vessel and the tube 16. From the tank 17 the material
is emptied by means of the regulating valve and pump or by any other suitable
means.
In this way the seed originally formed in cell or vessel No. 1, is continually
passed through all the other cells or vessels of the battery, being gradually
increased in size in each cell by the addition of thick juice or nourishing liquor
until it is crystallized up to the required degree, and discharged continuously
from the last vessel. The function of the first vessel is to prepare the seed for
use in the battery and keep the seed receiver filled,

page_text: The function of the vessels in the battery following the seed receiving vessel
is to increase the size of the crystals and concentrate the mass up to the required
density.
If it be desired to add molasses or syrup of a lower purity, this can be done in
the case of large apparatus by increasing the number of the vessels and dis-
charging continuously, or in the case of small apparatus the continuous discharge
might be dispensed with and the vessel preceding the last allowed to fill up whilst
the last is thickening up with molasses.
Having now particularly described and ascertained the nature of our said
invention, and in what manner the same is to be performed, we declare that
what we claim is:-
1. A process for the concentration and crystallization of saccharine or other
crystallizable liquids, all as hereinbefore described.
2. In the concentration and crystallization of saccharine and other crystal-
lizable liquids, a series of vessels in which the current of liquid flows from the
first to the last in the manner herein before described.
3. A process in which the concentration and crystallization of saccharine or
other crystallizable liquids is effected by having a battery of vessels, the first cell
of which is used to make the seed and the remaining vessels act as growers,
builders, or thickeners, all as hereinbefore described.
Dated this Twenty third day of August 1900.
JOHN MCNEIL,
CHARLES MCNEIL.