Improvements in Furnaces for the Desiccation, Incineration, and Carbonization of Precipitants or Solids Resulting from Sludge Carbonization of Precipitants or Solids Resulting from Sludge or other Substances liable to Putrify.
Year: 1886

page_text: Improvements in Furnaces for the Desiccation, Incineration, and
Carbonization of Precipitants or Solids Resulting from Sludge
Carbonization of Precipitants or Solids Resulting from Sludge
or other Substances liable to Putrify.
I RICHARD DE SOLDENHOFF of 71 St Mary Street Cardiff in the County of
Glamorgan, 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 :-
:
The above named substances are to be desiccated carbonized and incinerated by
the heat developed by the consumption of their own combustible compounds such
as carbon, hydrogen, phosphorous and sulphur; and in Furnaces as hereinafter
described.
In the accompanying drawings Figure 1 is a cross section of a group of Furnaces
constructed according to my invention; Figure is a horizontal section thereof
taken on the lines E F, G H, IJ, and K, L, of Figure 1: Figure 3 a longitudinal
section on the lines A, B, of Figure 11 Figure 4 is a similar section on the line C, D,
of Figure 1 and Figures 5 and 6 are detail views of parts.
The furnaces are to be built always in pairs that is to say, the least number to
be used is two furnaces situated side by side, but any even number of furnaces
may be employed.
Each furnace is composed of two chambers an upper one A and a lower one B.
The upper chamber A is the desiccating or drying chamber while the lower
chamber B is the incinerating or carbonizing chamber. The upper chamber A is
provided with one two or more openings A in the top, through which the said
chamber is to be charged with the material to be desiccated and with one or more
other openings; when one b is employed it is placed in the front whilst at the back
is a permanent closure and when two openings are employed one is placed in the
front end and the other 61 in the back end thereof.
Each of these end openings is large enough to permit a rabble to be passed
through it so as to level the material in the said upper chamber A. The openings
in the top are closed by means of cast iron covers; whilst those in the ends are
closed by means of doors as hereinafter described. Each of these upper chambers A
is situated above a lower chamber B and is put in connection with it by three
openings c, situated immediately underneath the charging openings a.

page_text: These openings c are closed with fire brick covers provided with wrought iron
handles by which they may be taken out through the charging openings a.
The openings c are for the purpose of enabling the material when sufficiently
dry to be passed through them from the upper chamber A into the lower
chamber B. The lower chamber B is provided with doors as hereinafter described.
Each lower chamber B is above three horizontal flues C, D, E, arranged in a
tier one above the other the arch or crown of the flue C constitutes the floor of the
furnace.
The floor of the top flue may be horizontal as shown or slightly inclined from
the centre to both ends or it may be inclined from the back to the front.
The top and bottom flues C, and E, are gas flues, the intermediate flue D is an
air regenerative flue. Each side wall is formed with a horizontal air flue F which
is in connection with another horizontal flue G below the same through a series
of openings d in the roof of said flue G. The flue G communicates with the oven
chamber B by openings e; and the air flue F, communicates with the said oven
chamber by openings f similar to openings e. From the lower flue G to the floor
of the flue C there are shown 28 vertical flues H but other numbers may be
employed these are repeated in every side wall except the last on the right hand
side and the last on the left hand side. These vertical flues H are gas flues to
carry the products of combustion through them into the flue C where they meet
with gases carried by similar vertical flues of next side wall. The gases therefore
meet in the flue C and after traversing together, the greater portion thereof pass
into the flue C¹.
From these flues C and C¹ the gases pass into flues E, E¹ and from there into
the main Blue J.
The first flue D on the left hand side receives the cold air which after traversing
through all said flues D passes into vertical flues K, K¹ whence it is distributed
into the upper air flues F and from thence through the openings d into the lower
air flues G or through openings finto the ovens. :
In some cases if necessary the gases would be passed intermittently into two
Siemens regenerators situated in the main flue between the ovens and the chimney:
so that the waste gases would traverse the regenerators before passing to the
chimney and the air passing into them intermittently would pass through one
of the regenerators at a time before entering the vertical flues K, K¹.
The working of the furnace is as follows:-
The material to be treated is charged first into the upper chamber A of the
furnace, to dry from whence after the moisture is expelled it is dropped into the
lower chamber B. In this lower chamber B the material operated upon, owing to
the heat of side walls and floors and owing to the presence of hot air delivered by
the upper air flue F will inflame and expel the gases. The gases partly burnt
in the oven, and partly in the flue will produce heat and render it to the
side walls.
The waste gases and the heat will after having escaped from the ovens pass into
the lower air flue G in which they mingle with the gases of the next oven, and
also with the hot air passing to the lower air flue G through the openings d in the
floor of the upper air flue. Therefore all the gases not yet inflamed in the furnace
will become ignited in the lower air flue G. The products of combustion will then
find their way through the vertical flues H by which they will be conducted to the
flue C under the floor of the oven and in which flue C the gases travelling in two
side walls both belonging to the same furnace but each used by gases of two
furnaces mingle together. A small part of the gases in this flue C in which they
meet will be taken off by an opening p into the flue E, whilst the bulk of the gases
in flue C will flow into the flue C₁ whence by an opening p' they will pass into
flue E-The cold air first enters the flue D and passes through similar flues from
one end of the block of furnaces to the other where by two vertical shafts K, K¹
as stated above it is led into two flues N, N¹, situated on the top of the furnaces.

page_text: From these the hot air enters all the upper air flues F, through openings
whence it is distributed into the ovens and lower air flues G, as described above.
When the material submitted to incineration in the lower chamber B of the furnace
has expelled all its gases and been reduced to the state of ash, the doors of the
furnace are opened and the ashes are rabbled out by hand or by special machinery
designed for that purpose. The doors of the furnace are made of wrought or cast
iron, and lined with four or five inches of fire bricks. The perfect closure of
furnaces is secured by luting them with clay from the outside.
The doors are suspended on hinges or are lifting doors; in the last case the
top of the furnaces will be provided with crabs or other lifting means to lift
the doors.
The moisture evaporating in the upper chamber A of the furnace will find its
way through the middle charging hole which will be left open for that purpose only
in case of wet weather the opening will be provided with a cover so as to protect
the inside of the chamber A from being wetted.
The floor of the lower chamber of the furnace B is not flat but is curved, or it
may have an undulated or serrated shape as shown at Figures 5 and 6 in order to
develop the heating surface of the floor.
The bricks in the side walls separating the lower chamber B from the flues G
and H are about three inches thick.
In case the Siemen's regenerators were applied the flues D and E would be
suppressed and the gases leaving flue C, C¹, would be directed into the main
flue and from there by an arrangement as described diverted to the regenerators.
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 :-
The peculiar construction and arrangement of furnaces substantially as herein
shown and described, and for the purpose stated.