An Improved Process for Preparing and Treating Lime; and Apparatus therefor.
Year: 1898

page_text: An Improved Process for Preparing and Treating Lime; and
Apparatus therefor.
I, HENRY JOSIAH HARDING, of 11, Blomfield Road, Paddington, London, W.,
Lime and Cement Merchant, do hereby declare the nature of this invention to be
as follows:-
-:
My invention relates to the slaking and preparation of lime and more particu-
larly lime of a hydraulic character, which unless properly divided does not, as a
cement attain the highest results of which it is capable.
To reduce the calcined limestone to its finest atoms and to preserve the same
from re-absorbing its carbonates, I first ascertain the character of the lime and
the least quantity of moisture required to naturally bring it to its greatest division.
The necessary moisture is carefully applied by means of a boiling spray or steam
jet, after which the lime so moistened is immediately placed in an oven or heated
chamber, from which the resulting product is conveyed to another chamber,
preferentially of a circular shape having an air-tight shaft of convenient dimen-
sions and height.
At the bottom of this chamber I introduce a blower or air pump of sufficient
power to carry all lime reduced to a given size. or of sufficient low specific gravity,
up and over the aforesaid shaft, over and round the top of which are built suitable
receptacles of sufficient capacity to admit of the dried lime atoms sinking or sub-
siding to the floor, or convenient bins or shoots in such receptacles, when relieved
of the forced atmospheric pressure which is not maintained beyond the air tight
shaft.
At the bottom of the shaft is a reducing machine which may be of various types,
such as edge runners or roller presses, for instance, but I prefer a circular basin
with balls made of hardened steel or porcelain, granite or other hard substances
and so as to produce when revolving a similar action to a pestle and mortar, thus
pulverizing such refractory atoms which may be of too great a specific gravity,
(either from absorbing too much moisture or from other causes), to be carried up
with the air blast, which latter is preferably heated.
With some limes I may use suitable chemicals mixed with and in the appli-
cation of both the heated moisture, steam or hot air, but especially the latter, to
assist in preserving the lime in its hydrated state.
Dated this 8th day of February 1898.
HUGHES & YOUNG.
55 & 56, Chancery Lane, W.C..

page_text: COMPLETE SPECIFICATION.
An Improved Process for Preparing and Treating Lime, and
Apparatus therefor.
I, HENRY JOSIAH HARDING, of 11, Blomfield Road, Paddington, London, W.,
Lime and Cement Merchant, 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 ;-
"
-
This invention relates to an improved process for preparing and treating lime,
and more especially lime of a hydraulic character, which unless properly divided
does not when employed for cementing purposes, attain the highest results of
which it is possible. The object of the said invention is to so treat the lime as
to render it capable of being more readily and effectually mixed with many other
ingredients in the preparation of concrete, mortar and the like, with the addition
of less water and no danger of expansion, and generally to render such lime of
more commercial value and utility than was heretofore possible. In order that
this my said invention may be the more readily understood and carried into
practical effect, reference is hereby made to the accompanying illustrative draw-
ing, wherein is shewn a sectional elevational view of the apparatus I. employ in
conjunction with the improved process.
In carrying the invention into practice, I reduce the calcined limestone to its
finest atoms, and to preserve the same from returning to its carbonate form until
required I first ascertain the character of the lime and the least quantity of
moisture required to naturally bring it to its greatest division. The necessary
moisture is carefully applied by means of a boiling spray.or steam jet, or, the
calcined limestone may. be immersed in boiling water, after which it is placed on
a hinged rack a¹ in an oven or chamber a which is heated in any suitable manner.
The said oven or heated chamber a communicates with a lower chamber. b, both
of which communicate with an air-tight shaft c, preferably of a cylindrical and
vertical form. At or near the bottom of the said chambers a and b I introduce
the nozzles d d of suitable blowers, air pumps or other forced draught apparatus,
each capable of producing a forced draught of heated air sufficient to carry all
the lime reduced to a given granular size, or of sufficient low specific gravity, up
and over the top of the shaft aforesaid. The said shaft c communicates at its
upper end with a receptacle (or it may be receptacles) e into which the dried lime
atoms, which are forced up the shaft in the manner before mentioned, sink or
subside, such lime atoms being conveyed away into bins or other receptacles. by
means of suitable shoots or their equivalent (not shewn).
In practice, it will be found that the forced draught from the nozzle d will be
sufficient to blow all the dried lime atoms off the rack a¹ in the oven or chamber a,
but where the said atoms are of too great a specific gravity (through absorbing
too much moisture or from other causes) to admit of every particle of such lime
being conveyed up the shaft c in this manner, such rack may be lowered and the
residue of the lime shot into the lower chamber b, in which may be situated a
suitable roller or other grinding apparatus, for the purpose of still further
reducing the aforesaid refractory lime atoms until they are of such a low specific
gravity as to admit of the forced draught from the nozzle d, carrying them up
the shaft c and into the receptacle e.
A suitable man-hole a² is provided in the upper or other convenient part of the
oven or chamber a, through which the calcined limestone is placed in the said
oven or chamber.

page_text: With some kinds of lime, I may employ suitable chemicals either by mixing
same with the lime in an early stage, or by applying such chemicals to the lime
by means of heated moisture, steam, or hot air (the latter means being preferable)
in order to assist in preserving the lime in its hydrated state.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I declare that what
I claim is
CLAIMS.
1. The improved process for preparing and treating lime, consisting in reducing
the calcined limes to its finest possible granular condition after which the suitably
moistened atoms are immediately heated in an oven or chamber from which they
are conveyed by a heated air-draught up an air-tight shaft into a receptacle, and
preserved in that condition substantially as specified.
2. In the improved process for preparing and treating lime and apparatus
therefor, the oven or chamber a having a man-hole a² and hinged rack a¹, in
which oven or chamber a the nozzle d of a suitable forced draught apparatus
projects, said oven or chamber communicating with an air-tight shaft c and a
lower chamber b also communicating with the shaft and having a nozzle d¹ for
the admission of heated air for conveying (in conjunction with the forced draught
admitted by the nozzle d) the lime of low specific gravity up the shaft c into a
receptacle e, substantially as described and as illustrated by the drawing.
Dated this 8th day of November 1898.
HUGHES & YOUNG,
55 & 56, Chancery Lane, London, W.C., Agents for Applicant.