Improved Apparatus for Utilizing the Waste Heat of Furnace Gases.
Year: 1895

page_text: Date of Application, 5th Feb., 1895
Complete Specification Left, 23rd Sept., 1895-Accepted, 26th Oct., 1895
PROVISIONAL SPECIFICATION.
Improved Apparatus for Utilizing the Waste Heat of Furnace
Gases.
I, JAMES PATTERSON, of 141 West George Street, in the City of Glasgow,
Engineer, do hereby declare, the nature of this invention to be as follows:-
This invention has for its object the utilization of the heat of the waste products
of combustion of boiler and other furnaces for the purposes of generating steam to
drive auxiliary engines such as those used for operating fans employed for inducing
draught in such furnaces, and of evaporating sea water to make up the feed for the
main boilers in steam ships.
The improved apparatus comprises a steam generating chamber composed of a shell
which may be conveniently made of the shape of a domed vertical boiler, but having,
in lieu of the usual furnace and chimney, a flue traversing it and communicating at
one end with the furnace uptake or chimney and at the other end with the inlet
eye of a fan or fans by means of which the hot waste gases from the furnace are
drawn through the flue. The steam generator is partially filled with water which
may be pumped in from the sea and the flue passes through the water space which
is thereby divided, water tubes expanded at their ends or otherwise fixed in the
plates which compose the flue shell serving to place the upper and lower com-
partments into communication and to offer an extremely large heating surface upon
which the hot gases impinge in their passage through the flue whilst other tubes
outwith the flue may be fitted to provide for circulation of the water. The fan is
fitted within a casing communicating with a receiver from which the products are
discharged into the upper part of the furnace chimney which is closed off from the
lower part by a movable damper. For the purpose of absorbing a large proportion
of the remaining heat of the waste gases and depositing the soot and other
impurities, water is passed through a pipe terminating in a chamber at the hub of
the fan and is thence led by small pipes and discharged in the form of jets or spray
on the blades or vanes, to keep them clean, and in the direction opposite to that of
the rotation of the fan in order by their reaction to facilitate the propulsion of the
fan. The steam raised in the generator is used to drive an engine connected to the
fan shaft or may be led to any other auxiliary engine. A pipe from the steam
space of the generator is led to the condenser of the main engines, and is fitted
with a valve loaded so that when the steam pressure is in excess of that required
for driving the auxiliary engines the surplus steam passes off to the condenser and
is there utilized to make up the feed for the main boilers. The exhaust from the
auxiliary engines may be connected to this pipe and also led to the condenser, and
in like manner the vapour arising from the water carried through the fan and
collecting in the receiver may also be discharged into the condenser.
In a modified form of the steam generator the flue is carried through the steam
space, and the water space is partitioned off or separated from the generator proper.
The water to be vapourised is forced through the water space and discharged in
the form of spray by nozzles or through jet orifices into or through the tubes
traversing the flue space and is there transformed into steam by impingement on
the interior surfaces of the heated tubes. Blow off cocks are provided to drain off

page_text: salt and scum collecting in the lower part of the steam space and sludge from the
water space of the generator.
Dated this 4th day of February 1895.
Improved Apparatus for Utilizing the Waste Heat of Furnace
Gases.
I, JAMES PATTERSON, of 141 West George Street, in the City of Glasgow,
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 :-
This invention has for its object the utilization of the heat of the waste products
of combustion of boiler and other furnaces for the purpose of generating steam to
drive auxiliary engines such as those used for operating fans employed for inducing
draught in such furnaces, and of evaporating sea water to make up the feed for the
main boilers in steam ships.
The improved apparatus comprises a steam generating chamber composed of a
shell which may be conveniently made of the shape of a domed vertical boiler, but
having, in lieu of the usual furnace and chimney a flue traversing it and communi-
cating at one end with the furnace uptake or chimney and at the other end with
the inlet eye of a fan or fans by means of which the hot waste gases from the
furnace are drawn through the flue. The steam generator is partially filled with
water which may be pumped in from the sea and the flue passes through the water
space which is thereby divided water tubes expanded at their ends or otherwise
fixed in the plates which compose the flue shell serving to place the upper and
lower compartments into communication and to offer an extremely large heating
surface upon which the hot gases impinge in their passage through the Hue whilst
other tubes outwith the flue may be fitted to provide for circulation of the water.
The fan is fitted with a casing communicating with a receiver from which the
products are discharged into the upper part of the furnace chimney which is closed
off from the lower part by a movable damper. For the purpose of absorbing a
large proportion of the remaining heat of the waste gases and depositing the soot
and other impurities, water is passed through a pipe terminating in a chamber at
the hub of the fan and is thence led by small pipes and discharged in the form of
jets or spray on the blades or vanes to keep them clean. The steam raised in the
generator is used to drive an engine connected to the fan shaft or may be led to
any other auxiliary engine. A pipe from the steam space of the generator is led
to the condenser of the main engines and is fitted with a valve loaded so that when
the steam pressure is in excess of that required for driving the auxiliary engines
the surplus steam passes off to the condenser and is there utilized to make up the
feed for the main boilers. The exhaust from the auxiliary engines may be
connected to this pipe and also led to the condenser, and in like manner the vapour
arising from the water carried through the fan and collecting in the receiver may
also be discharged into the condenser.
In a modified form of the steam generator the flue is carried through the steam
space, and the water space is partitioned off or separated from the generator proper.
The water to be vaporized is forced through the water space and discharged in the
form of spray by nozzles or through jet orifices into or through the tubes traversing
the flue space and is there transformed into steam by impingement on the interior

page_text: generator.
The accompanying drawings illustrate suitable arrangements for carrying the
invention into effect.
Fig. 1 being a vertical section of one arrangement,
Fig. 2 a horizontal section thereof, and
Fig. 3 a transverse section of such arrangement.
Fig. 4 is a vertical section, and
Fig. 5 a horizontal section of a modified arrangement.
Fig. 6 is a vertical section of the form of fan it is preferred to employ.
A is the steam generating chamber which the flue B traverses, one end of same
communicating with the furnace uptake or chimney C (a damper D being arranged
at the mouth of such flue for regulating or closing the opening of same), while at
the other end such flue B communicates with the inlet eye of a fan or fans E by
means of which the hot waste gases are drawn from the uptake or chimney
through the flue B.
In the arrangement shown in Figs. 1, 2 and 3, two fans E are employed, the
flue B being arranged between same and communicating with the casing of both,
whereas in the arrangement shown in Figs. 4 and 5 only one fan is employed.
In the arrangement shown in Figs. 1, 2 and 3, the steam generator A is partially
filled with water which may be pumped in, and the flue B traversing same divides
the water space into two parts, which water tubes b arranged in such flue place in
communication with each other and offer an extremely large heating surface upon
which the hot gases passing through the flue B impinge. Other tubes F outside
the generator also connect the two parts into which the water space of the
generator is divided, and serve to ensure the circulation of the water.
In the case of the arrangement illustrated in Figs. 4 and 5 the water space is
partitioned off from the generator proper (as shown at X), to the bottom part of
which it is confined, and the water to be vapourized is forced through such water
space and discharged in the form of spray by nozzles or through jet orifices H into
or through the tubes b traversing the flue B, and is there transformed into steam
by impingement on the interior surfaces of such heated tubes, and collects in the
top of generator A.
The casing of the fan or fans communicates with a receiver I from which the
products are discharged into the upper part of the uptake C through the passage K,
which opens into such uptake above the damper L, closing the upper part from the
lower part thereof.
The fan or fans E are preferably supplied with water for the purpose of
absorbing a large proportion of the heat still remaining in the waste gases after
their passage through the flue B, and which by becoming intimately mixed with
such gases in the fan or fans also serves to deposit the soot and other impurities
therefrom before such gases pass again into the uptake C through passage K.
The steam raised in generator A is led by a pipe M to the engine or engines N for
driving the fans (which may be of any suitable construction) or such steam may be
utilized for driving any other auxiliary engines.
A pipe O leads from the steam space A to the coudeuser of the main engines
and is fitted with a loaded valve P so that excess of steam will pass to such
condenser, and is there utilized as feed water for the main boilers. The exhaust
from the fan engines N may also be connected to pipe O, and the vapour from the
water passing through the fau or fans E and collecting in the receiver I may also
be discharged into the condenser.
Fig. 6 shows the form of fan it is preferred to employ, drawn to a larger
scale.
The fan blades X' are secured to a casting Y in the form of a hollow hub
(preferably of the conical form shown) such hub being fixed to the spindle Z
which is driven by any suitable means.

page_text: The outer side of the casting or hub Y is open to the atmosphere in the centre
and a pipe W projects through such opening and supplies water to the space at
the periphery of such hub. The rotation of the fan causes the water to be
thrown outwards and be retained in the space at the periphery of the hub, whence
it escapes through openings or tubes U and coming in contact with the blades X'
becomes intimately mixed with the gases admitted to the fan casing through the
inlet V, communicating with the uptake or passage through which such gases
are drawn by the fan.
The space at the periphery of the hub Y is preferably provided at intervals
with blades y which grip the water in such space, and prevent any slip of the
hub in relation to such water, but compel the latter to travel round with
the hub.
As the water escapes from the hub Y through the openings or tubes U, same
is replaced by water entering through the water pipe W. Before stopping the
fan for any reason the water supply through pipe W should be first turned off.
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. The combination of a fan communicating with the uptake or chimney through
which hot gases from furnaces or other sources are conveyed by means of a flue or
passage passing through a steam generator, such flue or passage having tubes
arranged therein which connect the upper and lower parts of the generator, and
against which the hot gases impinge on their way to the fan casing, all
substantially as specified.
2. The combination of a fan communicating with the uptake or chimney through
which hot gases from furnaces or other sources are conveyed by means of a flue
or passage passing through a steam generator, such flue or passage having tubes
arranged therein which connect the upper and lower parts of the generator, and
against which the hot gases impinge on their way to the fan casing, and into
or through which tubes water is forced in the form of a jet or spray, all
substantially as specified and as illustrated in Figs. 4 and 5 of the accompanying
drawings.
3. The improved fan for treating gases from furnaces and other sources consisting
in blades secured to a hollow hub fixed to a spindle, and open on one side to the
atmosphere, a water pipe projecting through the opening and supplying water to
the space at the periphery of such hub, while openings or tubes lead from such
space to the interior of the fan casing, all substantially as specified.
Dated this 23rd day of September 1895.
ALLISON BROS.,
Agents for the Applicant.