Improved Apparatus for Treating Asphalte.
Year: 1898

page_text: Date of Application, 10th Nov., 1898-Accepted, 7th Jan., 1899
COMPLETE SPECIFICATION..
Improved Apparatus for Treating Asphalte.
I, JOSEPH WINTER PATTISON, The Neuchâtel Asphalte Company, Travers, in
the Canton of Neuchatel and Republic of Switzerland, Manager, 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 apparatus for heating natural or artificial asphalt,
also applicable for manufacturing artificial asphalt.
Natural or artificial asphalt is a compound composed of calcareous matter and
of bitumen and is used in the form of powder or as cement. In the powder form,
asphalt is used for making road-ways and in the cement form for foot-paths.
According to its contents in bitumen, every asphalt possesses a fixed temperature
at which it becomes liquid, a second temperature at which its fusion is complete,
and a third temperature at which its decomposition commences. In order to
heat in every case the asphalt either during its manufacture at the works or
when being prepared for use to the required temperature without deteriorating
the bitumenous element by excess of heat, I have invented the apparatus which
forms the object of the present application for Letters Patent. This improved
apparatus consists essentially of a steam boiler, so connected by tubes with the
double bottom of one or more asphalt boilers, that these latter may be heated
either by steam or by hot water kept hot by steam coming from the steam boiler,
and the maximum heating temperature of this asphalt boiler or boilers can be
regulated by means of an adjustable safety valve, attached to the steam-boiler.
Referring to the accompanying drawings, I have illustrated by way of example
in Figure 1 in elevation and in Figure 2 in plan, a constructional form of the
apparatus, portions of the elevation shewn in Figure 1 being in section for greater
clearness. In these drawings, A indicates a steam-boiler having a safety valve B,
the counter-weight a whereof enables the pressure of the steam existing in the
boiler to be regulated from a little above one atmosphere up to that pressure
which corresponds to a temperature of 225° Centigrade. CCC are the heating
vessels or boilers for the asphalt, provided internally with rotary agitators b,
and each having its lower part surrounded by a double bottom c. These boilers C
are supported by a block of masonry D. The steam dome of the boiler A
communicates by means of a tube E with the double bottoms c of the vessels C,
and the passage of the steam into each of these double bottoms or steam-jackets
can be controlled by means of a cock d. From the bottom of each steam-jacket c
there passes a pipe e provided with a cock f, and all these pipes discharge into a
common conduit g which leads to the lowermost part of the boiler A, so that
the water produced by the condensation of the steam in the steam jackets c can
flow back to the boiler through the tubes e g. To the tube g is attached a
vertical pipe k, provided above with a cock h and communicating by means of
a bent tube placed nearly at the level at which the steam passes into the steam-
jackets c, with the same tube g, upon which is placed the valve i between the
tube and the tube j. If it be required to make use of this apparatus for pre-

page_text: paring asphalt cement in the works, for heating asphalt cement at the place of
operation, for making foot-paths, or for heating asphalt powder to make road-
ways of compressed asphalt, the pressure of the steam in the boiler is raised to
the pressure corresponding to the maximum temperature to which the material
placed in the vessels C is to be heated, and the cocks d, f, i, are then open and h
is closed.
The steam passing from the steam dome of the boiler A expands into
the steam-jackets c, heats the vessels C and the condensed water therefrom returns
to the boiler through e g. If, on the other hand, it is desired to prepare artificial
asphalt powder, the pressure of steam in the boiler is raised a little above the
atmospheric pressure, and the cocks d, f are opened and the valve i is closed;
the steam passing from the steam-dome of the boiler A expands into the steam-
jackets c of the vessels C, heats these latter and the water of condensation accumu-
lates in gec and during this time the cock h will be opened, so that the air
enclosed in the tube k can be driven out by the water rising in the said tube.
As soon as the water of condensation has risen in the tube k to the level at which
the bent tube j branches off, the cock h is closed and then the water of condensa-
tion passes from k into j and returns to the boiler A, whilst the vessels C are
heated by a water-bath in communication with the steam by the boiler A, and
kept hot by this latter, so that the materials under treatment in the vessels C
will not be heated to a temperature exceeding 100° Centigrade. When the above
described apparatus is made use of for laying the road or the like, the various
vessels A, C and so forth which compose it are preferably mounted on wheels.
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:
1. The improved apparatus for heating natural or artificial asphalt, and for
the manufacture of artificial asphalt, consisting essentially of a steam-boiler
and one or more heating vessels for the asphalt provided with double bottoms,
the said steam-boiler having a regulatable safety valve for controlling the pres-
sure of the steam supplied thereby, and limiting it to the maximum temperature
to which the material to be treated in the asphalt vessels is to be subjected; the
said steam-boiler moreover being so connected to the double bottom or bottoms
of the asphalt vessel or vessels. that the contents thereof may be heated either
by the steam from the boiler or by a bath heated by the same steam, substantially
as above described and shewn in the accompanying drawings.
LLION
EVIV
W. P. THOMPSON & Co.,
322, High Holborn, London, W.C., Patent Agents for the Applicant.