Improvements in Methods of Producing Combustible Gases for Heating and Lighting Purposes and in Apparatus therefor.
Year: 1890

page_text: Date of Application, 29th Aug., 1890-Accepted, 8th Nov., 1890
COMPLETE SPECIFICATION.
Improvements in Methods of Producing Combustible Gases for
Heating and Lighting Purposes and in Apparatus therefor.
BENJAMIN HOWARTH THWAITE of 37 Victoria Street Liverpool in the County of
Lancaster Civil Engineer do hereby declare the nature of this invention and in
what manner the same is to be performed, to be particularly described and ascer-
tained in and by the following statement:-
My present invention, in a measure, relates to improvements in former inventions
for which Letters Patent have already been granted to me Numbered 15621-1886
No. 6432-1888 No. 10224-1888 No. 16970-1888. But there are certain essential
features of difference constituting novel and important improvements, which enable
the following advantageous characteristics to be obtained.
The production of a highly thermic and luminous quality of gas, from oils, or
liquid hydrocarbons, with a minimum of condensable constituents.
The production of the gas-a compound of carbonic oxide and hydrogen technically
known as water gas, carbonic oxide or generator gas, separately or in combination,
in the same generator, by the regulation of specially contrived valves.
The method of producing the above gases in a way that does not involve the
accumulation of explosive mixtures of air and combustible gas.
The production of a gas of a fixed and uniform quality.
The cycle of the process of production using the apparatus shewn in Figures 1 & 2
see Sheet 1 of drawings is as follows:-
Fire grates are provided in each of a pair of generator vessels or chambers,
connected at the upper part by an aspiratory tube and at the base by a valve and
connections.
The aspiratory tube aspires the air in an ascensional direction, through the valve
and under the grate, and combustion ensues with the production of carbonic oxide,
which is drawn forward by the steam into the second chamber or vessel and flows
descensionally through the incandescent fuel therein the steam intermixed with
the gases, in flowing through the incandescent fuel is split up by a well known
chemical reaction.
The combined gases flow by means of an annular space and through cooling tubes
into the reversing valve, and from thence to the condenser en route to the gas
holder.
This process proceeds until the fuel in the downward flow chamber, or vessel,
becomes too reduced in temperature for chemical action to take place. When this
occurs the gas, steam, and air valves, are reversed, and the air flows into the other
chamber. In order to prevent an explosive mixture occurring under the grates, a
steam supply is directed thereunder for a short period sufficient to displace the air
and gas that may have accumulated
This cycle of operations is the basis of that involved when using apparatus shewn
in Sheets 2 3 & 4 of drawings. But instead of the aspiratory tube being fixed over
the level of fuel it is placed at the ground floor, and the aspiratory action is applied
to near the base of the fuel in second generator vessel, whereby the gases are drawn
therefrom and the aspiratory action is applied to the first vessel, the air flowing under
the grate and ascensionally through the fuel. The carbonic oxide produced being
aspired to the second vessel through a connecting flue passes descensionally through
the fuel contained therein escaping by an annular flue into a reversing valve which is
merely intended for diverting the flow of the escaping gases, and which valve may be
of the several forms shewn by figures viz. the balanced, the rotary, horizontal or
vertical and the sliding type.
The aspirator draws or induces the flow of the gas. The steam of the aspirator if

page_text: undecomposed by non-contact with fuel assists in its condensation in the removal of
the ammonia and sulphurous acid and any existing condensable hydrocarbons.
The aspirator is applied to the two vessels at alternate periods-first to one vessel,
then to the other as the condition of the fuel requires.
The reversal of the gas valves and the air valve, which latter is a separate apparatus
connected to the undergrates of the two vessels and which may have connected to it,
a steam jet air injector which latter is however only applied in such a way as to
preserve an inward pressure in the gas generating vessels so that there will not be an
explosive mixture of gas produced under the grates.
In order to enrich the gases and produce this enrichment from liquid hydrocarbons
I inject oil, preferably under high pressures and in well distributed streams, into or
over the fuel.
This liquid hydrocarbon is supplied to both vessels, the flow being directed to one
vessel or the other, the change of flow being effected during the reversal of the other
valves.
I prefer however to direct the oil spray into that vessel in which the descensional
flow of gas is taking place, so that as the gas is volatilised it escapes into the gas
mains but I may direct the oil spray into the vessel in which an upward and
ascensional flow of gases is proceeding. In this latter instance the gas is volatilized
with the ascending flow of gases and is fixed, or rendered permanent during its
passage through or in traversing the fuel in second vessel.
The arrangement of solid fuel feeding is automatic, and is such that although the
vessels are under aspiratory influence no serious volume of air can penetrate or be
in such proportions as to spoil the quality of the gas.
Before I fully and in detail describe the annexed sheet of drawings containing
figures illustrative of the apparatus required to effect my invention, I wish it be
clearly understood that 1 do not intend to be confined to the exact details therein
shewn as these may be modified without departing from the nature of this invention.
Referring to Figures 12 & 3 on Sheet 1 of drawings Figure 1 an elevation and
Figure 2 is a plan of the generators. Figure 3 a detail of reversing gas valve. The
essential characteristics of the generator may be enumerated as follows-a & b are the
generator vessels or chambers, lined internally with refractory material such as
firebricks, at the base of the generator vessels, I provide the ordinary clinker doors C
for providing adequate facilities for the removal of the clinkers and ash or other
incombustible residue.
Around the refractory lining or wall just referred to, and forming part of the
lining, I provide an annular cavity d through and by which the gas escapes
alternately from one side and then from the other, as the modus operandi of the
process requires, and the gas then flows through vertical pipes which are arranged so
as to partly cool the gas before it reaches the reversing valve.
The reversing valvef is shewn in detail by Figure 3 which is a longitudinal and
vertical cross section the kinematic and moving or actuating parts are described by
the following:—
The valve plates g¹ are suspended from a bearing h. The valve plates are
suspended opposite each other, and are controlled by a cross and pivoted lever i
which is pivoted in the centre at j on to a cranked bar k, the movement of which
from the fulcrum 7 opens one valve and closes the other, allowing the gas to escape
from one side or chamber into and through opening m. The gases after leaving the
reversing valve are further cooled and condensed by being compelled to flow
through the tubular condenser n, in traversing this condenser the remaining sensible
heat of the gas is transferred or transmitted to the air flowing to the base of fuel,
and required to assist in the processes involved in the production of the combustible
gases. Such condenser may of course be the ordinary type of water cooling
condenser or feed water heater type. The aspiratory arrangement for effecting the
flow of air and gas is as follows-an aspirator tube O is placed between, and connects
the two generator vessels a & b. The aspirator tube O is so arranged that the two
steam jets p are accessible from the outside and can thus be quickly removed,

page_text: examined and cleaned. The steam jets act, in their flow through the conical tubes,
as aspirators. These steam jets are connected with a steam supply, by the
pipes q&q and the reversal valve f. The movement of a levers fixed on the
spindle or actuating control shaft of upper platform and connected by a link or rod
to reversal valve freverses the direction of the flow of steam either into the pipe q or
the pipe q. By the movement of the same lever and by means of the connecting
rod t the main gas reversal valve f is simultaneously reversed. Instead of the
reversal lever requiring to be reversed by hand, I may utilize an automatic tumbling
gear arrangement fed by water from a head or elevation, for the purpose of effecting
the reversal movement of the valve, at definite periods automatically, regularly and
reliably. The aspiratory tube is provided with vertical tubes at each end thereof,
which may also be arranged so as to act as aspirators when the fires require to be
revivified. These vertical aspiratory tubes u, are supplied with steam jets for
effecting the necessary aspiratory action and are fed with steam by a pipe V. A
safety valve w is provided to the undergrate of each vessel a & b.
Figures 4 to 7 shew respectively a vertical section, a vertical side elevation, and
plan in section and a plan of top of gas generator vessels,-1 & 2 are the gas
generator vessels. The movable fire grates 3 are horizontal and rest upon a central
support block 4, which has two seats in each of its sides-one seat is intended for the
ordinary fire bars the other for the clinker bars. Between the movable grates 3 are
the fixed triangular grates 5, sloped or inclined from the sides so that the clinkers and
incombustible residue gravitate towards and upon the movable portion of the grates.
Clinker doors 6, are provided for each of the four movable grates. The under
sides of the fire grates of the two vessels are connected together by connections, in
the centre of which is an air reversal valve 7 that directs the air alternately under
the grates of one vessel or the other as the case may be.
At a certain distance above the grates, I provide the outlets 8, for the escape of the
gas-these outlets consist of special perforated refractory blocks uniformly, and
evenly distributed around the wall, and debouching into an annular cavity 9
formed by wrought iron plates, around the vessel side. This cavity may be lined
with refractory material. Above the level of outlets 8, provide and build in a
wall a course of oil injector blocks 10 each block consisting of perforated firebrick
provided with cone shaped perforators in the centre of which I fix the oil injector
pipes of nozzles 12.
The oil I inject by a head or pressure varying preferably from 20 to 60 lbs. per
square inch, it may be more or less. The high pressure by which the oil is injected is
however an essential feature of this invention.
The fireclay or refractory blocks for introducing the oil into the gas generator
chamber may slightly project beyond the inner face of side walls so that there is a
natural cavity forined by the fuel-by the angle of repose-and by which cavity the
spray of oil resulting from the oil being injected under high pressure, is distributed to
the fuel. The oil supply is distributed to the jets by a pipe 11 encircling each vessel,
and the oil is fed by small pipe branches 12 to each of the inlet blocks, each inlet
pipe branch may be provided with a fine bore needle valve for preventing or clearing
out obstructions. Each pipe is tapered down to a fine 1 inch or less bore, at the
termination, the jet pipe or nozzle projects into the centre of the refractory block 10.
The oil supply pipe 11 is provided with a reversal valve 13 by which the oil
is directed to one or the other vessel as the flow or currents of gas and air are
reversed.
Generally I prefer to have the oil supply directed on to the vessel that has a
descensional current or flow of gases; proceeding in this application, as the oil is.
volatilised in contact with the incandescent fuel;-it immediately flows to the outlet
by this arrangement, there is not the liability in any degree of the splitting up of the
hydrocarbon gases. But I may direct the oil in the vessel in which an upward or
ascensional current is established, so that the volatilised oil gas ascends with the
currents and flows into the second vessel through which it descends and becomes
thoroughly fixed in its passage and contact with said incandescent fuel.

page_text: .The gases escape through the outlet passages 8 and annular cavity 9, and finally
escape into the gas reversing valve f, which may be of the sliding type as shewn, or
be of the rotary or balanced and bell type as described elsewhere.
The arrangement of feeding the fuel is as follows:-
The coal is transmitted or conveyed by a spiral or other form of conveyor 14 by
which the coal or other fuel to be used is drawn or otherwise moved forward to the
feeding hoppers 15.
The fuel falls into the shoots 16, and is shot or projected forward by the move-
ment of the block 17 into hopper 18, and falling or gravitating on to the bell 19,
gradually overweights it, and the bell falls allowing the fuel to fall into
the generator 1 or 2, the bell is then lifted back into its original position by the
counterbalance weights, and thus prevents an outward escape of gas or an ingress of air.
The block 17 is forced forward by the coil spring 21 which is compressed by
the movement of the lever, and cam 22 the latter being fixed and revolving on
a shaft R¹.
The fuel can be fed directly into the hopper and on to the bell by sliding away the
top cover plate.
The reversal of the rotary air valve, the sliding of the gas reversal valve, and the
changing of the direction of the flow of oil through valve 13, are effected simultaneously
by means of a link chain that passes over sprocket wheels affixed to the shaft of the
rotary valve on the shaft of the sliding actuating valve, or spindle or shaft of oil
reversal valve..
The D slide valve f, I prefer to so arrange that it shall carry a supply of water
on its upper surface by which the sliding surface is maintained cool and in a workable
condition.
A secondary supply of oil, may be provided by the use of the steam jet oil
injectors, 26 & 27, each injector having steam and oil supply pipes, which are reversed
with the reversal of the other valves.
The spray of the oil from these injectors is directed towards the flue or passage 28,
connecting the two vessels together.
The lining of the vessels is so arranged that the fuel will easily gravitate downwards
without adhering to the sides.
Referring to Figures 8 to 12 of Sheet 3 of drawings.
Figure 8 is a vertical cross section Figure 9 is a plan in section of one vessel at
the level of the grate, and at the central plane of rotary air reversal valve, and the
connection to the second vessel. The air valve may be of the balanced type as shewn
in Figure 11 and be provided with a steam jet air injector. Figure 10 is a half plan
and section through annular cavity, and through perforated outlet block, and also a
half plan in section, through upper annular cavity which is provided with ports.
Figure 11 is a detailed section of balanced gas valve fin which the bell valves A are
balanced and suspended from a lever B. The bells fall into a water trough or mercury
filled seats C, which are constantly replenished with water or mercury-if this agent
is used by a constant flow for which a special head and supply of water with supply
connections and outlet pipes are provided.
The bell valves A work in a light sheet iron cover chamber D.
The shaft E forming the central fulcrum of the lever B, carrying at its ends the
bell valves, are actuated from the outside of the cover chainber D. Figure 12
represents a detail of the aspiratory tube arrangement used in one of the modifications
of apparatus shewn by Figure 1 and Figure 2 in Sheet 1 of drawings. Steam jets
are provided at D and at E between them is a flanged central junction which can
be easily removed for cleaning purposes. At each end of horizontal aspiratory tube
I may provide a vertical aspiratory tube having its upper outlet open to the atmosphere.
These tubes are only used when the fires have become too dead for the processes to he
effected satisfactorily, and the vertical aspiratory tubes permit the fires to be rapidly
revivified.
Referring to Figure 8.
It will be observed that the firebars are carried by a central hollow bridge H

page_text: dividing the grate into two parts. The clinker bearing bars J two or three in number,
are supported by ledges projecting from the inner surface of clinker door frames K.
The clinker bearing bars are simply formed thus and placed loosely on their supports.
Besides or in addition to these bars which enable thick masses of clinker to be
removed. provide a second support for the clinker bars by means of an upper
frame L, provided with perforations for the insertion of clinker bars, which perforations
are covered with a sliding cover plate M, having corresponding openings to those in
the side plate.
"2
The clinker doors are of the ordinary cross bar or swinging bar type, and call. for
no special description.
The outlet blocks 8 are shewn of the special form I prefer to use. The annular gas
cavity or flue 9, I also line with refractory bricks as shown.
The oil injection blocks 10 are of a special kind and so arranged as to enable the
oil spray to be well distributed.
An annular flue is provided in lining the vessel at the upper part, and this cavity in
each vessel may be connected by an aspiratory tube arrangement similar to the plan
shewn in Figures 1 & 2. The fuel is fed into vessel by means of an automatic
sliding arrangement see Figure 8. The fuel falls into the box D working in a
closely fitting frame Q. The fuel is moved forward by the crank action R and
connecting rod S and falls into generator vessels through a cavity T provided on the
slide frame.
The position of the sliding coal box as shewn in Figure 8 is when it is ready for
receiving the fuel from the hopper.
The fuel having fallen into the box D during its slow movement it is then
quickly drawn forward, and the box having a hollow base and this base sliding over
a corresponding opening in the frame, the fuel falls through, and the box is
returned by the forward motion of the crank, so as to be ready to receive a
second supply of coal. The movement of the box at the forward and backward
motion of the crank, is slow, and this permits the emptying and filling-of the box to
be effected.
Referring to Figure 14 on Sheet 4 of drawings.
This Figure 14 illustrates a complete vertical section of the modification of my
invention partly shewn by Figure 8 on Sheet 3 of drawings.
1 & 2 are the generators coupled together by the connection 28 lined with refractory
material. The annular cavities g₁ debouching into generator chamber by ports g₁₁
may be connected with the aspiratory arrangement F shewn by Figure 12 on Sheet 3
of drawings.
The oil injection arrangement is similar to that shewn in Figures 4 to 7, the valve 30
is intended for the reversal of the flow of oil.
The annular flue g for the escape of the gas is lined with refractory material or a
firebrick lining 31.
The flow of gas reversal valve f is of the rotary type working in its movement
through a horizontal plane, around a vertical hollow spindle 33.
The movable valve 32 is hollow and is maintained full of water fed by the hollow
vertical spindle-shaft 33. The valve casing 34 is deeper than the valve 32, so that the
hydrocarbons deposited on the sides, fall to the bottom of the valve casing 34 and can
be easily removed.
The flow of gas reversal valve fand flow of air reversal valve 7 is connected by the
same hollow vertical spindle 33, the movement of which therefore actuates and reverses
both valves as well as the oil flow reversal valve 30.
The movable firebars 3 are shewn in section the upper openings for the insertion of
the clinker bars are shewn at M.
The automatic fuel feeding gear is shewn in cross section and is actuated by the
driving shaft R¹.
The position of the sliding fuel box D, is when it is over the opening T uncovering
the chambers of gas generator vessels 1 & 2.

page_text: The gases escape through the gas reversal valve ƒ into the gas mains and
condensers.
The direction of the flow of gas is changed every half hour the direction of the
aspiratory effect being diverted to the generator vessel a.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same may be performed I declare that what I
claim is summarised as follows:-
1st. The method, by which and alternately producer gas, per se and then oil gas
may be produced in the manner substantially as herein shewn and described.
2nd. The method by which oil gas is produced in a vessel by and with the
descending currents of gases of carbonic oxide & hydrogen produced in another
vessel as they pass through the incandescent fuel in contact with which the oil is
volatilized.
3rd. The method of injecting oil in well distributed streams or jets under very high
pressure, first into one and then into the other of a pair of gas generator vessels
working in combination substantially as herein shewn and described.
4th. The automatic fuel feeding arrangement in combination with gas generators of
the type herein shewn and described.
5th. The valvular arrangements for effecting the reversal of the currents of air and
gas substantially as herein shewn and described.
6th. The aspiratory arrangements for inducing the flow of the gases substantially
as herein shewn and described.
7th. The firegrate arrangement shewn in figure substantially as herein shewn and
described.
Dated this 26th day of Amanat 1800
B. H. THWAITE.