An Improved Coal Dust Feeder for Furnaces.
Year: 1894

page_text: Date of Application, 26th July, 1894-Accepted, 29th Sept., 1894
An Improved Coal Dust Feeder for Furnaces.
I, ALFRED FRIEDEBERG, of 11/12 Wöhlert Strasse, Berlin, Kingdom of
Prussia, German Empire, Manufacturer 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 a device for feeding furnaces, especially boiler-furnaces,
with coal-dust, and consists in certain arrangements and combinations of parts
which will be more fully described hereinafter.
In order to make my invention more clear, I refer to the accompanying drawing,
in which similar letters denote similar parts throughout the several views, and in
which :-
Fig. 1 shows a front-view of my improved feeding-device, partly in section,
Fig. 2 is an upper view, also partly in section, and
Fig. 3 is a detail, shown in vertical section.
The construction is as follows: Several boxes b arranged in an inverted position
are secured to the upper portion of a common vessel a, so as to form a cover or
covers for the same. Vessel a is covered not entirely by said boxes b, but a space
is left, into which is inserted a hopper a¹.
Into the bottom or
cover respectively of each of the inverted boxes b
terminates a nozzle e forming the mouth-piece of the blast inlet-pipe d. The
latter is provided with a throttle-valve v. Said nozzles terminate into said
boxes 6 in such a direction, that they are adapted to whirl off that portion of the
coal-dust, which is indicated by k in Fig. 1. It will be seen, that this is the
portion supporting the coal-dust within funnel a¹.
Outlet-pipes c communicating at their outer ends with a stand-pipe or stand-
pipes extend from the side-walls of the boxes b. Said stand-pipe is held in a
vertical position by a bracket and is provided near its bottom with an opening h,
and with a slide or flap i adapted to close said opening.
Concerning the stand-pipe g, it is of importance that the exit, or delivery-end
respectively, of the same is situated above, or higher than the inlets of the pipes c
into said stand-pipe. The latter is furnished at its head, with a hopper-like body m
arranged horizontally, and containing, or embracing respectively, another hollow
or solid body n of similar configuration. The respective size of the two bodies is
such that there is remaining between them an annular space o adapted to act as a
channel for the material dispersed by the blast.
The several parts of the apparatus described up to now are rigidly connected
with a tube p. This connection is established at the bottom of vessel a by a
plate t, at the head of the same by pipe d already mentioned. Said pipe
communicates with tube p by an opening s.
is then in
Tube P is arranged on a fixed tube g, and may be turned on or around the
same. Said tube is provided with an opening r coinciding with openings of
piped when the apparatus is in its proper working position. Tube
communication with pipe d. Said communication will be interrupted as soon as
the whole apparatus is turned around tube q, as openings of pipe d will be closed
then by the wall of said tube q.
The whole apparatus is arranged in front of a furnace (especially a boiler-furnace,
as indicated for instance at R in Figs. 2 & 3) in such a manner, that if the
apparatus is in working position, the flange of body m lies close to the opening
of, or entrance to, the furnace. As long as the apparatus is in this position,
017

page_text: tube q and pipe d are communicating, and a blast of air pressed into tube g by
any suitable means is allowed to enter the boxes b.
Vessel a as well as hopper a¹ form the store-room for the coal dust to be
dispersed. The material is introduced into vessel a through the hopper, and is
filling said vessel up to the lower edge of the side-walls of the boxes 6; by said
walls, the coal-dust is hindered from entering the interior of said boxes b. There is
remaining, thus, a space between the surface of the coal-dust and the covers, or
bottoms respectively, of said boxes.
If, now, valve v is opened, the blast coming from tube 9 will flow through the
nozzles e into the boxes; the blast pushing upon the surface of the coal-dust
causes the latter to be whirled up, aud is driving the particles loosened by its
action into the channels c. By reason of the peculiar arrangement of the nozzles,
or by the direction given the blast by said arrangement respectively, there is
whirled off that portion of the coal-dust which is indicated by k in Fig. 1. Thus,
the other portion of the coal-dust supported up to then by said portion k will
loose its support, and will fall down into the space emptied by the action of the
blast. According to the quantity falling down into vessel a out of hopper a',
fresh material is automatically introduced into the latter by means of any suitable
contrivance. There is, consequently, a steady delivery of coal-dust to the furnace
as long as the blast is allowed to enter the boxes b.
The particles whirled off by the blast are carried away by the latter through
the stand-pipe g. By reason of the vertical position of said stand-pipe, and by
the upward direction imparted thereby to the blast as well as to said particles, all
larger or heavier parts, as pieces of coal and slag, are caused to fall down, and to
collect on the bottom of the stand-pipe. Said parts may be removed now and then
by aid of opening aforementioned.
The mixture of coal-dust and air when pushing upon the body n is deviated by
the latter, and caused to enter the annular channel o; by reason of the arrange-
ment of the two bodies m and n, and by the equal width of said channel o, the mixture
is equally distributed within the channel, entering in this state the furnace R.
In order to cleanse the furnace, and to remove residues of the fuel, the feeding-
apparatus must be swung off the furnace; this is performed by turning the
apparatus around tube q. The blast is automatically interrupted thereby as
openings of piped is closed by the wall of tube g; the feeding of the material,
consequently, ceases, and will commence again as soon as the apparatus is swung
back into its former, proper working position.
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
1. In a coal-dust feeding device for furnaces:
The combination with a vessel a adapted to receive the material to be dispersed,
of one or more boxes barranged in an inverted position within the upper portion
of said vessel, and forming the cover of the latter, a hopper a¹ arranged between
said boxes being adapted to convey the coal-dust into vessel a, and keep the latter
filled up to the side-walls of the boxes b, the latter being adapted to form an
empty space above the surface of the coal-dust, substantially and for the purpose
as described.
2. In a coal-dust feeding device for furnaces:
The combination with boxes b, and with a hopper a', of blast-nozzles e arranged
within said boxes in such a direction that the spread-cone resulting from the
function of said nozzles extends below said hopper; the latter being adapted to
refill the space emptied by the blast, substantially and for the purpose as
described.
3. In a coal-dust feeding device for furnaces:
The combination with pipes c adapted to lead away the dust whirled off by the
blast, of a stand-pipe or -pipes g having near its bottom an opening / adapted to

page_text: be closed by a flap i, the outlet or outlets of said stand-pipe or -pipes being on a
higher level than their inlets, substantially and for the purpose as described.
4. In a coal-dust feeding device for furnaces:
a,
and
The combination with a tube p adapted to hold the coal-dust vessel
communicating with the latter by a pipe d, of a fixed tube q having an opening r
communicating with said pipe d, said tube p being adapted to be turned around
said tube g, substantially and for the purpose as described.
5. In a coal-dust feeding device for furnaces:
The combination with a stand-pipe g, of a hollow body m arranged on the top
of said stand-pipe in front of the furnace proper R, said body m containing
another body n adapted to form with body m an annular channel o, the latter being
adapted to lead the mixture of coal-dust and air into said furnace R, substantially
and for the purpose as described.
6. In a coal-dust feeding device for furnaces:
The method of dispersing coal-dust, consisting in directing upon the surface of
a quantity of coal-dust, that is in the state of rest, a blast or blasts adapted to
whirl said surface up, and to carry away the particles loosened thereby, substantially
and for the purpose as described.
1004
ALFRED FRIEDEBERG.
Geo. H. Rayner,
37, Chancery Lane, London, W.C., Agent for the Applicant.