Improvements in and relating to Boiler Furnaces.
Year: 1896

page_text: Date of Application, 23rd Apr., 1898-Accepted, 17th Apr., 1897
COMPLETE SPECIFICATION.
Improvements in and relating to Boiler Furnaces.
I, JAMES HERMANN ROSENTHAL, of 147 Queen Victoria Street, in the City of
London, 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 to provide a boiler furnace for burning bagasse or
similar refuse fibrous material in combination with means for heating the air supply
and directing it through the fuel as it is fed into the furnace, for the purpose of drying
the fuel and facilitating its combustion.
In the accompanying drawings which illustrate the invention Figure 1 is a
longitudinal vertical section of the improved furnace and air heating arrangement as
applied for firing a water tube boiler, Figure 2 is a horizontal section of the same and
Figures 3, 4 and 5 are transverse vertical sections taken respectively as at the lines
1-1, 2-2, and 3-8 in Figure 1.
The boiler A which is shown in elevation is of the well-known Babcock & Wilcox
type and it is interposed between the furnace B and an air heater the latter being
BO situated as to absorb and utilise the waste heat from the products of combustion on
their passage to the chimney D. The furnace B which is enclosed by brickwork has
an inclined stepped grate E terminating at its lower end in a horizontal grate formed
by ordinary fire bars e, or a dumping grate, whilst at its upper end is a hopper F
through which the bagasse or other fuel is fed, the hopper being provided with
weighted doors F1 adapted to close automatically so as to practically seal the furnace.
Air in a honted state is admitted to the hopper F through perforations in its walls
from a casing G surrounding it and heated air is also admitted through porforations in
the dead plate E at the upper end of the stepped grate E, the heated air being
supplied through air trunks H fed by flues 1 leading from the heater O the direction
of flow being indicated by the arrows. Dampers J and K are provided for controlling
the air supply to the upper and lower parts of the furnace; and other dampers or doors L
at the sides of the furnace serve to admit air when desired through passages M
extending around and over the crown B' of the furnace and opening to the fire grate E.
The fire gasos from the furnace pass over a bridge B at rear and thence into a
combustion chamber B' in which the boiler A is placed the gases circulating around
the water tubes of the boiler as indicated by the arrows and thence passing through
the heater chamber C to the chimney. The heater is composed of a number of rows
of vertical tubes .c connected at top and bottom to air casings or chambers c¹ into
which the air is admitted or forced by a fan or blower N, the air being caused to
circulate up and down through the tubes as indicated by the arrows by suitable
subdivision of the air casings at top and bottom whilst the impingement of the hot
gases on the exterior of all the tubes is ensured by the interposition of baffle plates or
walls in the passage for the gases. The air is thus highly heated and is delivered
through the underground flue I and air trunks H to the hopper and furnace B at a
temperature sufficiently high to ensure complete combustion of the fuel.
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 :-
The combination with a steam boiler of a bagasso burning furnace and feeding

page_text: hopper constructed as set forth and an air heater arranged to absorb the waste heat
and to supply heated air to the furnace and hopper, substantially as described.
Dated this 22nd day of April 1896.
WALLACE FAIRWEATHER,
Chartered Patent Agent,
62 Saint Vincent Street, Glasgow, Agent for the Applicant.