Improved Smoke Consuming Furnace and Apparatus in connection therewith.
Year: 1897

page_text: Date of Application, 7th Apr., 1897
Complete Specification Left, 5th Jan., 1898-Accepted, 26th Feb., 1898
PROVISIONAL SPECIFICATION.
Improved Smoke Consuming Furnace and Apparatus in connection
therewith.
I, AUGUST KRIPPEL, of XVIII. Scheidestrasse No. 34, Vienna, Austria, do
hereby declare the nature of this invention to be as follows:-
This invention relates to an improved construction of furnace in which the
effectual consumption of the smoke is attained by the production of a very high
temperature of combustion in combination with a suitable supply of air both below
and above the furnace grate. For this purpose there is constructed above the fire
grate a fire brick arch or vault, the under surface of which is either made stepped,
if the grate is inclined, or it is made with transverse serrations if the grate is
horizontal, so that the flames and combustion gases strike against the edges of the
several steps or serrations, and thus have a whirling or eddying motion imparted
to them whereby they are effectually mixed with the air supply passing up through
the grate and also passing in above the grate, producing complete combustion of
the carbon.
The air supply below the grate has mixed with it a small proportion of steam
introduced through perforated pipes, which steam in becoming superheated on
passing through the incandescent layer of fuel expands and thereby opens up the
fuel so as to provide free passage for the air, and also diminishes the production of
slag so that the latter can be easily removed by a rake.
The upper or secondary supply of air is admitted continuously in regulated small
quantities from the front through a specially constructed fire door and also from
the rear during a short interval of time after each opening of the fire door when the
fire is stirred or fresh coals are introduced. Such air supply is for this purpose
introduced through a small slot at the fire bridge or rear wall of the furnace.
The fire door, which may be lined on the inner side with fire-clay, consists of a
chamber or divided by a vertical wall into 2 compartments, in which the air is
guided twice to and fro so as to become heated, and discharges at the upper edge of
the inner face of the fire-door through a very small slot a certain height above the
fuel.
According to the system of the boiler employed the air can be conducted in three
different ways to the air-slot at the fire bridge; in boilers with so-called under
firing, having a large ash pit the air passes through channels at the side of the ash-
pit, separated from the latter by iron walls and having a large cross section.
In boilers with internal furnace (such as Cornish Boilers &c.) the secondary air
passes through pipes of fire clay (silicate of magnesia) leading from the rear part of
the boiler through the flue, to the fire bridge; these pipes in addition to supply-
ing secondary air, have the further purpose of forcing the flame (which would
extend without this arrangement only on the upper part of the flue) to pass around
the central fire clay pipe over the whole internal flue-surface, effecting thus a con-
siderable augmentation of the heating surfaces.
In furnaces for locomotive and marine boilers the secondary air is conducted

page_text: by means of tubes (which are fixed in the rear-wall of the fire-box and serve instead
of stiffening bolts) to the combustion chamber above the grate. In all these 3 cases
after the automatic opening of the spacious air channels, the heavier external air
rushes into the air channels, forcing forward the warmer and thinner air, and enters
with a high velocity through the narrow slot at the rear end of the furnace below
the brick vault which ends there.
The direction of this current of secondary air entering from rearward towards
the fire-door is opposed to that coming from the fire-door below the fire brick vault,
Howing rearward, whereby the thorough mixing of both currents of air is effected.
The arrangement of the vault produced a heating temperature so far
above 1000° C. that the entrance of the relatively cooler secondary air is not capable
of reducing. this temperature below 1000° C. (the condition of a perfect combustion)
but on the contrary it augments this temperature by the supply of oxygen to
about 2000° C.
As mentioned above, the supply of secondary air is automatic and intermittent.
In all cases the air conductuctors are closed by lids or valves, which are put in con-
nection, by means of wire ropes running over rollers, with hollow regulating
cylinders.
As soon as the fire man opens the fire door to stir up or to feed on fuel, a cock
'connected with the fire door hinges is thereby turned, causing water to flow into the
said regulator cylinder in connection with the air-valves and effects the opening of
the same by any known means. At the same time a valve or cock at the bottom of
the cylinder effects the emptying of the cylinder, so that the cylinder, not being
as heavy as the air valve or it counterweight, is raised by the latter and the air
conducting-pipe is closed.
In order to effect a perfect consumption of smoke, even when much slag is on the
grate or when bad coal is used I employ a perforated tube behind the air entrance
slot, through which steam may be supplied, but only as long as the air valve is
open.
This steam then enters also from rear-ward above the grate below the vault, and
passes towards the fire-door acting as injector. Where it is necessary I provide
a counter as auxiliary vault or arch to protect the boiler walls and to prevent the
direct flame contact.
When the construction of the boiler demands it (for example in Babcox and
Wilcox Boilers) the doors for cleaning the water-pipes may be protected by a cover-
ing of fire-clay or by a water jacket against heating.
As this furnace acts quite automatically no skilled fireman is necessary and the
furnace can be served by anybody, while a great saving of coal and perfect con-
sumption of smoke is attained.
ABEL & IMRAY,
Agents for the Applicant.
COMPLETE SPECIFICATION.
Improved Smoke Consuming Furnace and Apparatus in connection
therewith.
I, AUGUST KRIPPEL, of XVIII. Scheidlstrasse No. 34, Vienna, Austria, 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 improved construction of furnace in which the
effectual consumption of the smoke is attained by the production of a very high

page_text: Fig. is a longitudinal section and
Fig. 7 a cross section through a ships boiler with such appliances.
Fig. illustrates a longitudinal section and Fig. 7 a cross section of a flame
flue with the smoke consuming device.
Fig. 8 shews part side view of a locomotive with section through the fire-box.
Fig. 9 shews a cross section through the fire-box, and Fig. 9* shews a front view of
the same.
Fig. 10 shews an enlarged front view of the fire door, Fig. 11 the vertical cross
section, Fig. 12 the horizontal cross section, Fig. 13 shews a detached detail. Fig. 14
is a part longitudinal section and Fig. 15 a front view of a water-tube boiler (system
Babcock and Wilcox) Fig. 16 is a cross section, and Fig. 17 a longitudinal view of
the detail of the pipe-conduit between the water chamber and pipe conduit.
In all figures similar letters indicate the same parts.
In order that during the production of the heating gases no transmission of heat
by radiation shall take place to the surrounding iron walls that are internally in
contact with water which would cause a diminution of temperature in the furnace,
the arches are provided made of refractory material, constituting a bad conductor
of heat (for instance fire-clay, silicate of magnesia, dinas-brick and the like).
The heat of the ash pit is used for the preliminary heating of the secondary air, the
resulting simultaneous cooling of the ash pit increases the durability of the grate.
For this purpose I employ the air channels b (Figs. 1, 2, 3 and 14) below the grate
at the sides of the ash pit, which channels are separated from the latter only by iron
plates b. These iron plates take up very quickly the heat radiated downwards
from the grate and impart the same to the air in the spacious air-channels. After
the opening of the air slide valve r heavier external air rushes into the air channels
and presses the warmer and rarified air through a narrow slot d at the rear end of
the furnace, from which it discharges with a high velocity into the furnace.
This slot is made of gradually diminishing area towards the furnace and is
arranged in such a manner that the relatively cool air enters as high as possible
above the layer of fuel but below the fire-brick a flowing as far as possible from the
grate in the direction towards the fire-door into the highly heated furnace chamber;
there the air expands suddenly and is mixed thoroughly with the meeting com-
bustion gases coming from the fire door. By this means the exhausting action
of the chimney is already effected at the front of the furnace and a high initial
velocity of the supply of cold external air is obtained.
Also the disadvantageous heat radiated against the fire door is utilised in the
same way, as it also effects the preliminary heating of the air which enters from the
outside and is conducted to and fro in the spaces formed in the door before it enters
the furnace as high as possible, above the grate. The cooling of the fire door by
the entering fresh air is advisable on account of the high temperature in the furnace.
The mixing of the combustion gases, with the primary air entering through the
grate and with the secondary air entering through the fire door c is effected by the
serrated or stepped construction of the vault a as the gases strike against the edges
and have thus a whirling motion imparted to them. The number of channels b
depends upon the size of the boiler and upon local conditions.
When bad coal is used or when much slag is on the grate or when the com-

page_text: bustion is "forced," an augmented supply of secondary air through the slot & can
be effected by opening the valve e Fig. and admitting steam through the per-
forated pipe f behind the slot d which steam acts as injector in propelling the
atmospheric air into the combustion chamber. Steam may be also admitted below
the grate through the perforated pipe h by opening the valves y Fig. 3. This steam
passes through the slag, limits the production of the latter, loosens the same and
becoming expanded by the high temperature forms new passages for the primary
air coming from below. The continual supply of secondary air would cause a great
excess of air, and consequently a waste of fuel; therefore the supply of secondary
air is only effected intermitently for very short periods without the assistance of the
stoker.
As soon as the fire door c (Figs. 1, 3, 4, 6, 10 to 12 is opened the arm i (Fig. 5)
turns with it and by aid of the links and it opens water cock-plug /, whereby the
hollow sheet iron cylinder n (Figs. 1, 3, 4, 6, and 94) is filled with water from the
pipe conduit m. After the cylinder is filled with water it is heavier than the slide
valve of the air channel b; the air-valve is therefore lifted and opened by the
sinking cylinder n.
At the same time the water gradually escapes from through a lower valve o
and flows into the cylinder p (below the former) whereby the cylinder n becomes
emptied after a certain time and being again lighter than the air valve r it is
consequently lifted by the latter.
From the cylinder the water is discharged through the pipe q.
The flowing off of the water from the cylinder into the receptacle that is to
say, the time for maintaining open the valve r may be regulated by adjusting the
valve o so that the commencement and ceasing of the admission of secondary air
is effected quite automatically.
In order to protect the boiler walls against the direct flame I provide the arches s
(Figs. 1, 2, 8, 9 and 14).
The furnace door e (Figs. 10 to 13) is divided by a partition c¹ into two com-
partments; the air enters at in the first chamber, is guided around the parti-
tion c, enters the second chamber and passes through slot et into the combustion
chamber at such a height above the fuel that the contact of the fuel with fresh air is
prevented. The fire-door is efficiently cooled by this draught.
At Fig. 14 is shewn a water tube boiler with a water tank u rivetted to the clean-
ing door t.
The feed water is supplied to this tank through pipe and through the pipe wit
is led off to the feed tank of the boiler.
by
These pipes are so arranged that they may be easily removed when required for
opening the cleaning door to clean the boiler. For this purpose the supply and
discharge pieces of the water conduits are constructed in form of looped pipes v
and w (Figs. 14 to 17) which are pressed air-tight against the mouth pieces
means of yokes with screws and by caoutchouc washers y. As, owing to the high
temperature, a production of steam in the water tank is possible, the top of the
tank is arched, and from the highest point of this arch a steam discharge pipe 1
(Fig. 15) leads into the ash-pit. By this arrangement not only is the cleaning door
preserved but also a feed-water heater is created.
In Cornish, Tischbein, and other boilers of similar construction the secondary air
is conducted from rearward through the flue by means of pipes B of refractory
materials (fire-clay, silicate of magnesia etc.) as shewn at Figs. 6 and 7*.
In furnaces for locomotive and marine boilers (Figs. 6, 8 and 94) the secondary
air is conducted by tubes D (either one tube as at Fig. 6 or several tubes as at
Figs. 8 and 9) which are fixed in the rear wall of the fire-box and serve instead of
stiffening bolts.
In a locomotive furnace the mouth of the air channel D' is situated at the front of
the engine above the smoke-box door, so that the speed of the engine is utilised for
producing a compressed air supply. The air channel becomes flatter and wider
towards the front and is made to fit close against and follow the curved shape of the

page_text: locomotive boiler, so that heat will be transmitted from the latter to the compressed
secondary air supply as it flows towards the furnace.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed, I declare that what I
claim is:
-
go
1. In a smoke consuming furnace with automatically regulated air-supply im-
mediately after opening the fire-door, the arrangement whereby an air valve which
is automatically actuated by the opening of the fire door admits external fresh air
through channels either leading from rearward to the fire-bridge (in internal
firings as at Fig. 6, 6 and 8) or situated at the sides of the ash-pit and only
separated from the same by iron partitions, whereby the air is supplied in such a
manner at the fire bridge, or at the rear wall of the furnace, that it flows in a direc-
tion opposite that of the combustion gases against a fire brick arch or vault the under
surface of which is either made stepped or serrated in order to effectually mix the
secondary air entering through the fire-door, with the combustion gases, sub-
stantially as set forth.
2. In a smoke consuming furnace the combination of the fire-door e with an
arm which on opening the door effects the opening of a water cock by means of
rod and lever whereby the movable receptacle n which is connected to the air
valve is filled with water so that the receptacle thus weighted lifts the air valve
and enables a supply of secondary air to be effected through the fire bridge or rear
wall, the water being there gradually discharged from the vessel n so as to allow
the air valve to descend again and cut off the air supply substantially as described.
3. In a smoke consuming furnace such as is referred to in Claims 1 and 2, for
Cornish and similar boilers with internal firing, the supply of secondary air from
rearward through the flue to the fire bridge by means of tubular channels of fire-
brick, silicate of magnesia, and the like, substantially as described with reference
to Figs. 6 and 7 of the drawings.
4. In a smoke consuming furnace such as is referred to in Claims 1 and 2 the
supply of secondary air through the walls of fire boxes in locomotive and marine
boilers by means of tubes serving instead of stiffening bolts, substantially as
described with reference to Figs. 6, 8 and 9 of the drawings.
5. In a smoke consuming furnace such as is referred to in Claims 1 and 2 the
use of channels for the supply of secondary air, extending from the furnace close
against the surface of the boiler to the front end of the engine so that the air supply
entering there is both compressed by the speed of the engine and is heated by the
boiler, substantially as described with reference to Figs. 8 and 9 of the drawings.
Dated this 5th day of January 1898.
ABEL & IMRAY,
Agents for the Applicant.