and eventing the Emission or Smoke from Furnaces.
Year: 1886

page_text: DRAGOR, and eventing the Emission or
Smoke from Furnaces.
I, FRANK WHITE, of 40 Queen Street, Walsall in the County of Stafford, ·
engineer, do hereby declare the nature of this invention to be as follows:-
This invention refers more especially to steam boiler furnaces, and has for its
object improved means for mixing with air the escaping products passing from the
furnace grate over the bridge, and also the protection of the boiler plate from the
intense heat occasioned by the combustion resulting from such mixing; but
the improved means, according to this invention, by which the air is mixed with
the escaping products, aforesaid, is applicable also to other descriptions of furnaces
from the grates of which the escaping products pass away over a bridge.
I will first describe my invention in its application specially to a steam boiler
furnace. The bridge is constructed hollow, in the manner frequently employed
in cases where it is desired to consume the smoke, or otherwise with a suitable air
flue therein. In the case of a cylindrical boiler fired underneath, the top of the
bridge is struck to a sweep concentric with the boiler, so as to leave a segmental
annular space between such top and the bottom of the boiler, of say six to twelve
inches deep. The air opening in the bridge is carried out to the top. The space
between the top of the bridge and the underside of the boiler is built in with fire
brick so as to leave a protecting thickness of brick say 1 to 3 inches thick next to
the boiler plate, of a width equal to the thickness of the bridge, and so as to leave
openings at frequent intervals between the top of the bridge and the underside of
the protecting thickness aforesaid. The products escaping from the furnace grate,
passing through the openings, aforesaid, mingle with the fresh air supplied through
the bridge, and thus the streams of escaping products and air being, respectively,
divided up so as to ensure the contact of each smaller stream of escaping products
with a small stream of air, a thorough mixture of the air and escaping products
takes place attended with thorough combustion and consequently with the con-
sumption of any smoke passing over from the grate, and the emission of smoke
from the furnace into the chimney flue is effectually prevented. The boiler plate
is protected from the intense heat at the point where the escaping products and air
го

page_text: mingle, by means of the protecting thickness of fire brick before-described. The
piers of brickwork forming the divisions between the openings, aforesaid, are
formed to radiate, and these divisions act in supporting the protecting thickness
immediately under the boiler. This protecting thickness and the radiating
divisions are formed preferably of T-headed bricks, the head of each T forming
a segment of the protecting thickness, so that the heads of the whole set of bricks
when put together form, the complete protecting thickness of brickwork. The
stalks of the T-s form the radiating divisions. The air opening in the top of the
bridge is carried up also through each radiating division, so as to give a better
circumferential distribution of air in each opening.
When the furnace is carried inside the boiler, as in the case of a Cornish or
Lancashire boiler, the top of the bridge is formed as a segment of a circle concentric
with the boiler flue, and the radiating divisions and the protecting thickness of
brickwork under the boiler plate are carried therefrom. In this case, the curves
of the protecting thickness under the boiler plate, and of the segmental top of the
bridge, are, of course, the inverse of those employed in the case of the externally
fired boiler. The protecting thickness or arch of brick work not only protects the
plate from the intense heat due to the mixture of the air with the escaping
products, but acts also as a support to the crown of the flue at this point and thus
strengthens it against the tendency which internally fired flues have to come down
at such point. The radiating divisions of course add materially to the support of
the brick arch, and consequently therefore to the crown of the flue.
Openings of the character before-described, above a hollow bridge, or otherwise
in connection with a suitable air supply flue, may be employed for the purpose of
causing a thorough mixture of air with the escaping products from the furnace
grate, for the purpose of consuming smoke passing from the grate and preventing
the emission of smoke from the furnace, in the case of furnaces generally in which
the products from the fire grate pass over a bridge, such, for instance, as puddling
and heating furnaces employed in the manufacture of iron.

page_text: Improvements in Means Employed for Consuming Smoke Passing
from the Grates of Furnaces, and Preventing the Emission of
Smoke from Furnaces.
I, FRANK WHITE, of 40 Queen Street, Walsall in the County of Stafford,
engineer, 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, reference being had to the accompanying drawings and the
letters of reference marked thereon (that is to say) :-
=
This invention refers more especially to steam boiler furnaces, and has for its
object improved means for mixing with air the escaping products passing from the
furnace grate over the bridge, and also the protection of the boiler plate from the
intense heat occasioned by the combustion resulting from such mixing; but
the invention is applicable, also, to other descriptions of furnaces from the grites of
which the escaping products pass away over a bridge.
I will first describe my invention in its application specially in the case of an.
externally fired steam boiler, and in doing so will refer to figures 1, 2 and 3 of the
drawings herewith, of which figure 1 is a longitudinal section through the grate
and bridge and front end of the boiler having this invention applied thereto;
figure 2 is a transverse section taken on line x x of figure 1; and figure 3 is a
detail view which will be hereinafter described.
The same letters of reference occuring upon both the figures 1 and 2 indicato
corresponding parts.
A is the boiler, B the fire-bar surface, and C the bridge. The bridge is formed
hollow, or with an air flue a, and the top b b of the bridge is struck to a sweep
concentric with the lower side of the boiler so as to leave a space of, say, about
eight inches between the curve of the underside of the boiler and the curve of the
top of the bridge. Into this space are built a number of T-headed bricks c c c etc,
with the heads c against the underside of the boiler and with the stalks d d d etc
radiating therefrom and bearing upon the upper curved surface of the bridge.
Openings e e e etc, for the passage of the products of combustion from the furnace,
are thus left between the heads c c c etc, the radiating stalks d d d etc, and the top
of the bridge. The flue a in the bridge runs out along the curved top thereof and
thus air is supplied through the flue a to the openings e e e etc. The products
escaping from the furnace grate, passing through the openings e e e etc. mingle with
fresh air supplied through the bridge, and thus the streams of escaping products
and air, being respectively, divided up so as to ensure the contact of each smaller
stream of escaping products with a small stream of air, a thorough mixture of air and
escaping products takes place attended with thorough combustion and, consequently,
with the consumption of any smoke passing over the grate, and the emission of
smoke from the furnace into the chimney flue is effectually prevented. The boiler-
plate is protected from the intense heat at the point where the escaping products
and air mingle, by means of the protecting thickness of fire-brick formed by the
heads of the bricks coc etc., and the heads assist also, by butting against one
another, in maintaining the bricks in position..

page_text: In order to give a more thorough mixture of air with the escaping products
from the furnace, the stalk of each T-headed brick is divided transversely as shewn
by figure 3 (which is a transverse vertical section, to an enlarged scale, of one of
such bricks), so as to form an opening or flue therethrough corresponding to the
flue a in the bridge, and thus air may flow up from the flue a, not only into the
lower side of the openings e e e etc., but also into each side of the openings e e e etc.,
from the openings formed by dividing the stalks ddd etc. of the T-headed bricks;
and, in order to more firmly hold the divided parts of the stalk together, or in their
relative position, a wall or diaphragm may join such parts as shewn by figure 3a,
which is a section taken on line x x of figure 3 but with the wall or diaphragm
added thereto.
Any well known or convenient means may be adopted for regulating the admis-
sion of air to the flue a, such, for instance, as a valve f opened and closed by means
of a rod f', operated either by hand or by clock mechanism in a well known
manner frequently employed hitherto for regulating the passage of air to a hollow
bridge.
Figures 4 and 5 illustrate the application of this invention in the case of an
internally fired boiler. Of these figures figure 4 is a longitudinal section through
a short length of the internal flue tube, shewing the bridge and inner end of
the grate; and figure 5 is a transverse section through the boiler. The latter
section is taken at a point in the length of the furnace grate. The parts corre-
sponding to those illustrated by figures 1 and 2 are correspondingly lettered, and
in all cases corresponding parts are similarly lettered in both views. Referring
specially to figure 4, D is a supplementary bridge between the inner end of the
grate and the hollow bridge C, to prevent fuel or ashes being pushed into the lower
openings above or around the bridge C, and a space is left between the bridges to
allow of the passage of the escaping products from the furnace. The top of the
bridge C is formed concentric with the flue tube, and the stalks of the T-headed
bricks radiate from the centre of the flue, and the heads of such bricks bear
around the concave surface of the tube. In this case the T-headed bricks act as a
support to the crown of the tube and thus strengthen it against the tendency
which internally fired flue tubes have to come down over the bridge. h is a pipe
for conveying air to the hollow bridge.
In
Figures 6 and 7 illustrate the application of this invention, by way of example,
to a heating furnace. Figure 6 is a longitudinal section through the grate of such
a furnace, and the part of the heating chamber immediately adjacent thereto, and
figure 7 is a transverse section taken on line y y of figure 6. Parts corresponding
to those shewn in the previously described views are correspondingly lettered.
this case, as will be seen, the T-headed bricks are placed, with their stalks vertical,
between the top of the hollow bridge and the crown of the furnace, the latter
being protected by the heads from the intense heat of the flame over the bridge.
g is a flue from the hollow bridge to the front of the furnace, and g¹ a baffler or
other regulator to control by hand the admission of air.
I find that
The T-headed bricks may be of any convenient dimensions.
two inches is a convenient thickness both for the heads and stalks.
It is not essential to employ T-headed bricks for the purpose stated, though
they are much to be preferred, as parts corresponding to the heads may be formed
separately to parts corresponding to the shanks, that is to say, a protecting thick-
ness of brickwork may be simply carried on piers corresponding to the stalks of
the T-headed bricks; nor is it essential to employ a protecting thickness of brick-
work, either in the form of T-heads or otherwise, though such is very much
preferred, as plain bricks (that is without projecting heads), or corresponding piers,
may be employed in lieu of the T-headed bricks, being fixed to bear up against
the boiler-plate, or the crown of the furnace, as the case may be so as to divide the
space between the bridge and boiler-plate into a number of openings for the
purpose described, and such plain bricks or piers may have openings therein and
also walls or diaphragms as described,

page_text: 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. Consuming smoke passing from the grate of a furnace and preventing the
emission of smoke from such furnace by dividing up into small separate streams
the products of combustion passing from the furnace grate, and mixing same with
corresponding streams of air, substantially as described.
2. The means for consuming smoke passing from the grates of furnaces and
preventing the emission of smoke from furnaces, substantially as described.
3. A protecting thickness of brickwork supported on piers carried on the
furnace bridge, so as to leave openings between such protecting thickness of
brickwork and the top of the bridge, in combination with an air flue within the
bridge, and also the modification in which bricks or piers are employed without
the protecting thickness of brickwork, substantially as described, for the purpose
set forth.
4. The T-headed bricks in combination with a bridge having an air flue therein,
substantially as described and shewn, for the purpose set forth.
5. A transverse opening formed through the stalk of a T-headed brick (or
through other brick or pier) employed in combination with a bridge having an air
flue therein, and also the modification thereof in which a wall or diaphragm is
employed, substantially as described, for the purpose set forth.
STEPHEN WATKINS,
Wolverhampton and Walsall,
Agent for the Applicant.