AN IMPROVED ARRANGEMENT OF AIR AND SMOKE PASSAGES IN THE SETTING OF RETORT AND MUFFLE "FURNACES
Year: 1884

page_text: I ARTHUR WILLIAM LOVELL REDDIE of the Office for Patents, Bream's
Buildings, Chancery Lane in the County of Middlesex, Patent Agent do hereby.
declare the nature of my Invention for AN IMPROVED ARRANGEMENT OF AIR
AND SMOKE PASSAGES IN THE SETTING OF RETORT AND MUFFLE "FURNACES"
and in what manner the same is to be performed, to bo particularly described and
ascertained in and by the following statement:-
This Invention relates to the setting of retorts and muffles, and consists in a
novel arrangement of the air and smoke passages whereby the air necessary to
support combustion is preheated by the escaping gases, and is automatically
drawn in below and above the furnace in variable proportions suitable to the
conditions of the fuel in the grate, and whereby also the products of combustion
are utilized to heat the water in a tank below the fire bars for the purpose of
protecting the fire bars from burning and accelerating the combustion of the fuel.
In the accompanying Drawing Fig. 1 is a longitudinal vertical section through
the centre of a retort furnace constructed according to this Invention.
Fig. 2 is a sectional elevation taken on the lines H1, H2, and J, of Fig. 1.
Fig. 3 is a sectional plan view taken on the lines A A, B B, C C, D D and E E
of Fig. 2; and
Fig. 4 is a vertical section taken on the line F F of Fig. 2.
The fuel is introduced on the grate a through the opening b which can be closed
by a door c in an airtight manner. Slag and ashes are removed through the
opening & which can also be closed by a door e in an airtight manner.
If the grate
charged with fuel and if the two doors cand e are closed, no cold
exterior air can come to the fire-place. The entire air required for the combustion
is then admitted in a stream whose volume is regulated by the slides f, at g into
the furnace at the right and the left, passes through the channels and h¹ in the
direction of the arrows, and divides into two streams, the primary air of combustion
being led through the slits i from the right and the left, beneath the grate, and so
to the fire place; while another part of the air which has entered at g 9 goes from
[Dries 1

page_text: the channel ¹ through the channel into the channels h³ where its quantity is
regulated by the slides k, and thence it enters through the slit 7 as secondary air of
combustion into the furnace.
By this arrangement of air passages it happens that when there is a large mass
of fuel in the furnace a greater quantity of secondary air is absorbed by the
furnace, which air is necessary to the combustion of the carbonic oxide then being
formed in a more abundant quantity; whereas a greater quantity of primary air
is on the contrary absorbed, and a less quantity of secondary air introduced, when
there is a smaller layer of fuel. In this manner a self-acting regulation of the
quantity of the two kinds of air takes place according to the height of the layer
of fuel. The products of combustion after having passed in a uniform manner,
through the furnace, enter the smoke channel m and pass from front to rear, pass
down through n, and go through o from back to front, and through p from front
to rear to the chimney flue. On their passage through these channels the escaping
smoke and gases yield up a great deal of their heat to the air for supporting
combustion passing through the air channels h h h² and h³, and they can also be
utilized for the evaporation of the water in the tank q. This iron tank below
the grate is kept constantly filled with water as high as possible and the steam
resulting from the heated water protects the fire bars from burning away, and is
then by passing through the hot fuel, converted into hydrogen and oxygen. The
combustion of this hydrogen and of the so formed carbonic oxide takes place after-
wards when these gases are brought into contact with the secondary air of
combustion entering above or at the back of the furnace.
The above described heating by means of fire grates or furnaces may be applied
to retort and muffle-furnaces provided with retorts or muffles up to the number of
nine, tho' seven is a preferable number.
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. In a setting for retorts and muffles the arrangement of air channels h¹² h³,
flues m n o p and doors or slides, such as f, k, for pre-heating the air necessary to
support combustion, by the escaping smoke and gases, and for varying the volume
of heated air delivered respectively above and below the furnace, according to the
height of the fuel therein, substantially as described and shown on the accompanying
Drawings.
2. In a setting for retorts and muffles the combination with a water tank q
situate below the furnace, of the smoke flues p p passing beneath the said tank for
the purpose of facilitating the conversion of the water therein into steam, as herein
shown and described.