Improvements in Apparatus for Bleaching Minerals.
Year: 1893

page_text: Date of Application, 6th June, 1893-Accepted, 25th Nov., 1893
COMPLETE SPECIFICATION.
Improvements in Apparatus for Bleaching Minerals.
I ERNEST GIBSON of 28 Meldon Terrace South Shields, in the County of
Durham, Chemist, 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 :-
My invention relates to an improved apparatus for heating minerals (such for
instance as calcium, magnesium barium strontium and the like) during the process
of bleaching, and a method of cleansing same after leaving the bleaching bath or
baths, for the purpose of eliminating therefrom all traces of acids or other
chemicals or impurities, liberated during the process, or may be held in solution
by the liquor employed therefor, the principle object of my invention being to
provide a method and means of imparting heat to the said minerals during the
process of bleaching, that at no time shall or can exceed 212° F., and without
diluting the strength of the bleaching liquor, as obtains by injecting steam thereinto
for this purpose in the methods hitherto employed.
In order that my invention and the manner of using the same may be fully
understood, I have hereunto appended a sheet of drawings in which,
Figs. 1 and 2 are plan and front elevation respectively of a bleaching bath
constructed according to my invention.
Fig. 3 is a longitudinal vertical section of the same, shewing the method I employ
in washing or cleansing the minerals as these are removed from the bleaching bath.
Fig. 4 is a like section to Fig. 3, illustrating an alternative method of construct-
ing and arranging the same.
I carry my invention into effect by constructing of fire clay, porcelain, or glazed
earthenware, or of iron, enamelled internally, for the purpose of resisting the
influence of the acids or other chemicals or materials that may be employed in
the process of bleaching, a preferably rectangular bleaching bath A, provided with
a broad rim B, and this I cause to rest upon the rim of, so that the body of A dips
into, an iron vessel or tank C, containing water, built into a brick or other flue D,
in such a manner, that a passage or space exists between D and C. The heat
employed may be from that of a fire kindled at E, for which a door E' is provided,
so that the flan:es therefrom may pass around C for heating the water therein, or if
a furnace be at hand I may convey some of the heat therefrom through suitable
conduits to an inlet F in D (Fig. 2) in lieu of or in addition to the fire at E, or I
may employ, if available, high pressure steam from any source, and cause this to
enter F and pass around C for the same purpose, a suitable chimney or outlet for
the heat or steam being provided at G, and, if necessary, a suitable safety valve H
may be provided (Fig. 3) the aperture covered by H being also used, for filling the
boiler or tank C.
The bath A may be perfectly rectangular without a break therein as at Fig. 4,
but, preferably, this would be constructed with a mouth or outlet aperture A', as in
the remaining figures, provided with a flange in which is formed slots a and b for
the reception of a sliding door J, which may be rendered water tight by the means
of a screw e, passing through a threaded hole in a plate d, arranged to engage with
slots efformed in the flange of A', and parallel with a b, or by any other suitable
means. A lid or cover K (shewn by dotted outline in Figs. 2 and 3) may be
provided for the bath A, in order to prevent the escape of noxious fumes therefrom,
and this may be fastened to A by any suitable means, and if by bolts and nuts,
holes or apertures would be provided in the rim of K and the rim B for that
purpose.
The minerals to be bleached, and the chemical or other liquid usually employed

page_text: for the purpose, would be placed in the bath A, and if necessary covered by K in
the manner stated, and the water in C heated by either of the means previously
cited, and as the temperature of this was raised, so also would be the contents of A
to a corresponding degree, and as the temperature of the water in C, could not at
any time exceed boiling point, I thereby insure that the bleaching liquor will not
exceed this, and so I am enabled to preserve an even temperature for the bleaching
process.
When the bleaching is complete I place beneath the mouth A' of A, one end of
a metallic or earthenware chute L, the opposite end of which leads into the highest
end of a tilted perforated cylinder M, caused to revolve by any convenient or
available means, and upon this impinges several sprays of water from a supply
pipe N, which also throws a stream of water N¹ upon the chute L in the direction
of its fall. The door J is then raised, and the minerals scooped, shoveled or
otherwise removed from A, through A', and shot into L, and by the combined
influence of gravity and the force of N' the minerals pass into and through the
cylinder M, and by this means the minerals are cooled, and cleansed from all
impurities, and after passing from M the minerals may pass through a second or
third bleaching, by being treated a second or third time in the manner described,
not necessarily through the same bath, as any number of these may be provided
constructed in the same manner, but in certain cases, the application of heat may
be dispensed with in the baths subsequent to the second, and may be the first, as the
bleaching liquor after the first bath usually, or in some cases, differs therefrom.
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.
1st. In an improved apparatus for bleaching minerals the combination of a fire
clay, earthenware or enamelled iron bleaching bath A placed within, and resting
upon a vessel C, containing water, and built into, or otherwise surrounded by a
flue D, and heated by means of a flame, hot air or steam passing through D, thus
ensuring that the minerals and the bleaching liquor in A shall not exceed a
temperature of 212° Fh., substantially as and for the purposes herein described and
shewn by the accompanying drawings.
Dated this 5th day of June 1893
GEO. THOS. HYDE,
4, Moorfields, Fore Street, London, E.C., Agent for the Applicant.