IMPROVEMENTS IN APPLYING HEAT IN THE MANUFACTURE OF ARTIFICIAL FUEL, WHICH IMPROVEMENTS ARE APPLICABLE TO THE PREPARATION OF ASPHALTE, AND FOR OTHER PURPOSES
Year: 1842

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, EDWARD
BELL, of the College of Civil Engineers, Putney, in the County of Surrey,
Professor of Practical Mechanics, send greeting.
WHEREAS Her present most Excellent Majesty Queen Victoria, by Her
Letters Patent under the Great Seal of Great Britain, bearing date at West-
minster, the Twenty-ninth day of September, in the sixth year of Her reign,
did, for Herself, Her heirs and successors, give and grant unto me, the said
Edward Bell, Her especial licence, full power, sole privilege and authority,
that I, the said Edward Bell, my exors, aditiors, and assigns, or such others
as I, the said Edward Bell, my exors, adiñors, or assigns, should at any time
agree with, and no others, from time to time and at all times during the term
of years therein express, should and lawfully might make, use, exercise, and
vend, within England, Wales, and the Town of Berwick-upon-Tweed, my
Invention of "IMPROVEMENTS IN APPLYING HEAT IN THE MANUFACTURE OF
ARTIFICIAL FUEL, WHICH IMPROVEMENTS ARE APPLICABLE TO THE PREPARATION
OF ASPHALTE, AND FOR OTHER PURPOSES;" in which said Letters Patent is
contained a proviso that I, the said Edward Bell, shall cause a particular
description of the nature of my said Invention, and in what manner the same
is to be performed, to be inrolled in Her said Majesty's High Court of Chancery
within six calendar months next and immediately after the date of the said
in part recited Letters Patent, as in and by the same, reference being
thereunto had, will more fully and at large appear.

page_text: NOW KNOW YE, that in compliance with the said proviso, I, the said
Edward Bell, do hereby declare that the nature of my said Invention, and
the manner in which the same is to be performed, are fully described and
ascertained in and by the following statement thereof; that is to say:―
In the manufacture of artificial fuel, where pitch or other bituminous
matters are employed, and also when preparing asphalte and mixtures of pitch
and other bituminous matters in combination with sand, pebbles, and other
materials, for the purposes of paving and covering other surfaces, considerable
difficulty is experienced in applying heat economically when stirring and
mixing such matters when operating on large quantities, owing to the slow
manner in which heat penetrates through large masses of such materials, and
it is consequently difficult to stir and intimately blend and combine hard and
gritty matters with the pitch or other bituminous matters when carrying on
such processes. Now my Invention relates, first, to the application of currents
of heated air into the mass of materials under process, such heated air more
readily keeping the pitch or other bituminous matters in a melted or fluid state
whilst the process of mixing is going on.
Secondly, my Invention relates to applying a hollow shaft or axis; with suit-
able hollow blades, to allow of the same being kept heated during the process
of stirring and mixing pitch or other bituminous matters with other materials.
And, thirdly, my Invention relates to the application of melted pitch or other
bituminous matters through the hollow axes of a stirrer, in order to mix such
materials in preparing artificial fuel, and when preparing other matters for
paving roads and for covering other surfaces.
And in order that my Invention may be fully described and readily carried
into effect, I will proceed to describe the means pursued by me in performing
my Invention.
In preparing or manufacturing artificial fuel, where pitch or other bitu-
minous matter is used and also in preparing asphalte and other matters for
for the covering of roads and other surfaces when pitch or other bituminous
matter is used which requires heat to facilitate its being mixed with the
other matters employed, I use an iron pug mill, or machine of a like kind,
similar to what is used for grinding clay; and I prefer to apply heat around
and under the external surface thereof to aid the other means hereafter
described for heating the matters under process. And in such pug mill I
apply, a hollow shaft, the lower end of which is open, and works through a hole
at the bottom of the pug mill, there being a projecting ring or collar a few
inches up the hollow shaft, which rests on the bottom of the pug mill, and thus
prevents any matters passing through the hole in and through which the hollow

page_text: axis works. Under the bottom, and covering the hole through the pug mill,'
there is a pipe affixed, which is connected with a suitable air-heating appa-
ratus, through which currents of air are propelled by means of blowing
machinery. And the description of air-heating apparatus which I prefer is
such as is now constantly used for heating air for applying hot blast in the
manufacture of iron, or of smelting of iron stone or blast furnaces, as by such
description of apparatus air may with facility be heated to very high degrees of
temperature with but comparatively little destruction of the apparatus employed.
The knives or blades which are affixed to the hollow shaft are also hollow, and
along the backs thereof several small holes are formed, through which the
heated air is forced as the axis revolves, by which means the materials under
process will be more readily and completely mixed than when using heat only.
at the outer surface of the vessel containing the matters to be mixed; and at
the same time the knives or blades will be kept highly heated, by which they
will be prevented being clogged by the bituminous matters adhering thereto,
and thus the power necessary for stirring such mixtures of materials, will be
reduced. Or in place of causing heated air to pass through the hollow axis
and the knives or blades affixed thereto, I can apply melted pitch, or other
heated and fluid bituminous matter, through the hollow axis and through the
knives, by which heat may be applied to the knives, and the fluid pitch or
other bituminous matters introduced will thus be readily mixed with the other
materials in the pug mill. And to facilitate the operation it is better to have a
close cover for the pug mill in order to allow of the air and vapour within to be
exhausted by suitable machinery, by which this fluid bituminous matter, sub-
jected to the pressure of the atmosphere, will be forced into the mass of matters
in the pug mill; or pressure may be applied to force the matter or fluid matter
when the pug mill is open. I would remark, that when manufacturing arti-
ficial fuel, where pitch and small coal are used, I generally mix them in the
granular state by first breaking the pitch into small pieces which will pass
through a sieve with meshes a quarter to half an inch square, which I mix:
with a shovel with small coal, and then keep the pug mill charged with the
mixture, and the pitch will be melted and combine with the small coal, and be
delivered from the mill in a suitable state to be moulded and pressed in moulds,
as heretofore practised. Or I use the bituminous in a heated and fluid state,
and pour it into the pug mill as the small coal is charged into the pug mill;
and such is the case when combining other matters with pitch or other bitu-
minous matters for paving and the covering of surfaces. Or I can mix the
Buid and heated bituminous matters by placing the small coal in closed iron
ressels capable of being closed, so as to allow the air from within to be partially

page_text: exhausted, and then, by allowing the fluid bituminous matter to flow into such
vessel through a syphon or other suitable apparatus," the pressure of the
atmosphere or of a force pump or other apparatus quickening the process of
mixing the various matters. I then remove such matters so mixed, and
submit them to the operation of the pug mill, as above described.
Having thus described the nature of my Invention, and the best means I
am acquainted with for performing the same, I would wish it to be understood
that I do not confine myself to the particular details herein described, provided
the peculiar character of either part of my Invention be retained. But what
I claim is,
First the mode of applying heat in the manufacture of artificial fuel, and
also when preparing asphalte or other preparation of pitch or other bituminous
matter with other materials, as herein described, by the application of streams
of heated air amongst the materials under process.
Secondly, I claim the mode of applying heat when mixing pitch or other
bituminous matters with other materials, by applying hollow, heated agitating
or stirring apparatus.
And, thirdly, I claim the causing the heated and fluid bituminous matter to
be introduced through the agitating or stirring apparatus, as above described.
In witness whereof, I, the said Edward Bell, have hereunto set my hand
and seal, this Twenty-eighth day of March, in the year of our Lord
One thousand eight lundred and forty-three