Improvements in Evaporating or Condensing Milk and other Liquids.
Year: 1889

page_text: Date of Application, 28th May. 1889
Complete Specification Left, 28th Feb., 1890-Accepted, 5th Apr., 1890
PROVISIONAL SPECIFICATION.
Improvements in Evaporating or Condensing Milk and other
Liquids.
We, WILLIAM POWELL BRANSON of Chase Works, Clapham in the County of
Surrey Coffee Merchant and HARRY WILLIAM NEILD of Shoe Lane in the City of
London Engineer do hereby declare the nature of this Invention to be as
follows:-
When milk and various other liquids are boiled in vacuum at comparatively low
temperatures the vapour rising from the heated surface at the bottom of the pan often
does not pass freely through the liquid in the vessel, but carries with it a considerable
portion of the liquid in the form of froth and bubbles, which rise up in the pan and
if the operation is continued pass into the condenser. This occasions considerable
loss of the liquid it is desired to condense besides the evaporation is retarded and
practically cannot be carried on with advantage.
We have found this can be remedied and controlled by admitting at the bottom
part of the pan beneath the liquid to be evaporated a fine jet of air the effect of this
appears to be to keep the liquid in motion and facilitate the free passage of the vapour
through the liquid and prevent an undue accumulation of froth and by regulating
the current of air the froth or bubbles can be controlled at any height in the pan
found desirable and the amount of evaporation is very considerably increased. The
quantity of air required to be admitted to do this is very small and does not
appreciably reduce the vacuum or increase the work required to be done for
maintaining same.
Dated th
1
1000
CARPMAEL & Co.,
Agents.
COMPLETE SPECIFICATION.
Improvements in Evaporating or Condensing Milk and other
Liquids.
We, WILLIAM POWELL BRANSON, of Chase Works, Clapham, in the County of
Surrey, Coffee Merchant, and HARRY WILLIAM NEILD of Shoe Lane in the City
of London, Engineer, 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 :-
When milk and various other liquids are boiled in vacuum at comparatively low
temperatures the vapour rising from the heated surface at the bottom of the pan
often does not pass freely through the liquid in the vessel, but carries with it a
considerable portion of the liquid in the form of froth and bubbles, which rise
up in
the pan and if the operation is continued pass into the condenser. This occasions
considerable loss of the liquid it is desired to condense besides the evaporation is
retarded and practically cannot be carried on with advantage.
We have found this can be remedied and controlled by admitting at the bottom
part of the pan beneath the liquid to be evaporated a fine jet of air, the effect of this
appears to be to keep the liquid in motion and facilitate the free passage of the
vapour through the liquid and prevent an undue accumulation of froth and by
regulating the current of air the froth or bubbles can be controlled at any height in
the pan found desirable and the amount of evaporation is very considerably increased.
The quantity of air required to be admitted to do this is very small and does
[Price bi1

page_text: not appreciably reduce the vacuum or increase the work required to be done for
maintaining same.
Figure 1 of the drawing annexed is a vertical section of an ordinary vacuum pan
having fitted to it at the bottom a pipe of small diameter through which air may be
admitted to the interior of the pan.
A is the vacuum pan heated at the bottom by steam in a steam jacket A' and in
coils of pipe B in the interior of the pan in the ordinary manner.
C is the pipe by
which a jet of air can be admitted to the pan. Preferably on the top of the pipe we
place a valve D for controlling the admission of air to the pipe and preferably also
we place above the valve D a vessel E filled with cotton wool resting on a perforated
plate E' to filter the air as it passes to the pipe as shown in section on a larger scale
at Figure 2. The pipe is carried upwards in the manner shewn in Figure 1 so that
it may be controlled from the ordinary working stage.
Where the pipe Crises up through the steam jacket A¹ and pan A tight joints may
be made in the manner shewn in the section Figure 3.
For a vacuum pan of 6 feet diameter we have found it sufficient to use an inlet jet
of about of an inch in diameter
Having now particularly described and ascertained the nature of our said inven-
tion and in what manner the same is to be performed we declare that what we
claim is :-
1. In the process of evaporating or condensing milk or other liquids in a vacuum
pan the admission of a small jet or jets of air into the vacuum pan below the liquid
which is being evaporated or condensed for the purpose of preventing an undue
accumulation of froth.
2. The construction of evaporating pans with a small pipe passing into the bottom
of the pan and fitted at its outer end with a cock by which the passage of air into the
pipe can be controlled.
0011
1000
CARPMAEL & Co.,
Agents.