Improvements in Evaporating Brine and other Solutions.
Year: 1892

page_text: Date of Application, 17th Dec., 1892
Complete Specification Left, 16th Sept., 1893-Accepted, 21st Oct., 1893
PROVISIONAL SPECIFICATION.
Improvements in Evaporating Brine and other Solutions.
I, Sir LowTHIAN BELL, Baronet, F.R.S. of Rounton Grange, Northallerton
in the County of York, do hereby declare the nature of this invention to be as
follows:-
:-
In the Specification of a former Patent granted to me No. 17564 in the
year 1888 I have described the evaporation of brine for the manufacture of salt by
providing a chamber beneath a salt pan into which waggons containing blast furnace
slag in a highly heated state are introduced. The chamber was filled to a certain
depth with water from which steam was generated in the chamber by the heat of
the slag and this steam played upon the bottom of the salt pan and heated the
Or as I mentioned by way of alternative I sometimes employed a current
of air which was passed through the chamber; the air in this case was required to
serve as a heat carrier for the conveyance of heat from the slag balls to the bottom
of the salt pan.
same.
There are inconveniences attending both of these methods; if water be
employed the slag balls are liable to break on coming into contact therewith and
difficulties thus arise; when air is used it is found not to be efficient as a heat
carrier and it does not convey away the heat with sufficient rapidity to prevent the
slag waggons enclosed in the chamber from becoming over heated.
The object of my present invention is to overcome these difficulties; I do not
admit water to the chamber beneath the salt pan but I supply steam to it, preferably
the exhaust steam from a steam engine; this steam coming into contact with the
slag balls and other highly heated surfaces withdraws heat from them and on these
coming into contact with the bottom of the salt pan it communicates to it the heat
which it has previously absorbed. The apparatus which I employ is very similar
to that described in the Specification of my former Patent but the chamber has a
level floor which is a great improvement and by preference three lines of rails are
laid along the floor; the slag waggons stand side by side on these rails; they are
made to travel forward at intervals from the entrance where they are admitted in a
highly heated state, to the exit where they are so far cooled as no longer to be
advantageously available as a source of heat.
Dated this 16th day of December 1892.
LOWTHIAN BELL.
COMPLETE. SPECIFICATION.
Improvements in Evaporating Brine and other Solutions.
I, Sir LOWTHIAN BELL, Baronet, F.R.S., of Rounton Grange, Northallerton,
in the County of York, 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 the. Specification of a former Patent granted to me No. 17564 in the
year 1888 I have described the evaporation of brine for the manufacture of salt by
providing a chamber beneath a salt pan into which waggons containing blast
furnace slag in a highly heated state are introduced. The chamber was filled to a
certain depth with water from which steam was generated in the chamber by the
beat of the slag and this steam played upon the bottom of the salt pan and heated
ונם..'.

page_text: the same.
a
Or as I mentioned by way of alternative I sometimes employed
current of air which was passed through the chamber; the air in this case was
required to serve as a heat carrier for the conveyance of heat from the slag balls to
the bottom of the salt pan.
There are inconveniences attending both of these methods and it is the object of
my present invention to overcome these difficulties; I do not admit water to the
chamber beneath the salt pan but I supply steam to it; preferably the exhaust
steam from a steam engine; this steam coming into contact with the slag balls and
the highly heated surfaces of the vessel containing it withdraws heat from them
and on these coming into contact with the bottom of the salt pan it communicates
to it the heat which it has previously absorbed. The apparatus which I employ is
very similar to that described in the Specification of my former Patent; it is
illustrated by the drawing annexed.
Figure 1 is a longitudinal section. Figure 2 is a plan with a portion of the pan
removed and Figure 3 is a transverse section.
a is the salt pan, b a chamber beneath it, c c are the slag waggons, d d are
entrance doors, ee are apertures in the arches above the doors or in any other
convenient position into which pipes for admitting waste steam to the chamber are
set. is a steam outlet. The width of the pan is generally such as to admit of
three lines of rails being laid beneath it. There are longitudinal partition walls bl
between the lines of rails dividing the chamber into several compartments each
with its own door, which is opened only to allow a train of slag waggons to be
admitted to or withdrawn from the compartment.
In practice I have found that the portion of the pan bottom immediately above
the slag balls has not a sufficiently extensive surface to withdraw the heat from the
highly heated steam, consequently it is advisable than the pan should extend
beyond the waggon chamber b with a low chamber g beneath it communicating
with the waggon chamber and of a height sufficient only to give free passage to
the steam beneath the pan allowing it to pass along until it is condensed.
For the purpose of preventing a loss of steam from two of the chambers while
the door of the third is open for the purpose of introducing a fresh set of slag balls
the partition walls are continued to the further end of the pan.
In practice I find that the slag space requires about one third of the length of
the pan while the remaining two thirds can be heated during the cooling and
condensation of the steam after it has performed its work under the first third of
the pan. The relations however of these two divisions in point of length will
depend on the quantity of steam and of slag balls at command. In a pan having a
length of 75 feet by 25 feet broad with three lines of rails, each line of rails may
receive four slag balls which will afford sufficient heat to raise 30 tons of water in
the form of steam to the desired temperature and to carry on the evaporation
efficiently for 24 hours. This applies to slag balls of the ordinary dimensions say
four tons and of the temperature at which they are usually ready to leave the blast
furnace.
Practically the whole or nearly the whole of the steam will be found to be
condensed before it reaches the outlets f at the far end of the pan.
In case it is desired to expedite the withdrawal of the heat from the slag a
portion of the condensed water may be conducted so as to fall on the slag balls.
The steam so generated will in its turn receive an addition of heat in the same way
as the steam supplied from the exhaust pipes of the steam engines.
The brine is admitted at the far end of the pan and the salt as it falls is raked
out in the usual way.
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 :-
The means for evaporating brine and other solutions consisting in providing

page_text: beneath the pan a chamber into which waggons containing the hot slag balls are
admitted and into which also waste steam is blown to be heated by the slag balls,
and to circulate beneath the pan substantially as described.
Dated this 12th day of September 1893.
LOWTHIAN BELL.