Improvements in the Manufacture of Artificial Fuel.
Year: 1892

page_text: Date of Application, 26th July, 1892-Accepted, 27th Aug., 1892
COMPLETE SPECIFICATION.
Improvements in the Manufacture of Artificial Fuel.
We ROBERT FERGUSSON STRONG of 56 Burton Crescent, in the County of
London, Civil Engineer, and ALEXANDER GORDON of 27 Cheapside, also in the
County of London, Merchant, 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 relates to the manufacture of artificial fuel suitable for the
formation of blocks or briquettes which during combustion will emit little or no
black smoke. Furthermore, the fuel is inexpensive and gives a maximum of
heating power with the production of as small a percentage of ash or unconsumed
residium as is compatible with the complete absorption of the sulphurous and other
deleterious and smoke forming gaseous products of combustion. The principal
ingredients which we use in the manufacture of our artificial fuel, are:-(1) coal-dust,
coke, small coal, breeze, peat, lignite, charcoal, petroleumn, sand, or other
carbonaceous material or materials; (2) hydraulic lime; and (3) rock or other
common salt or sulphate of soda.
To these, we sometimes add cellulose, pitch, or other bituminous or gummy
material according to the kind of coal dust or other carbonaceous material used, and
I vary the proportions of the ingredients according to the purpose for which the
fuel may be desired, or the degree of hardness or consolidation of the particles
which the finished block or briquette is required to possess. When using
anthracite coal dust, peat, lignite, or other carbonaceous material of close compact
texture, or which under ordinary conditions smoulders during the process of com-
bustion instead of burning with a flame, we find that the following ingredients will
make a satisfactory fuel when used in about the proportions stated.
These ingredients are ground and intimately mixed together in a cold and natural
state and sufficient water is added to form the whole into a plastic mass which
may then be moulded or otherwise formed into blocks or lumps of desired size and
shape.
The hydraulic lime from its setting or cementing nature serves to unite or bind
the ingredients together and to consolidate the finished block or briquette. It also
during the process of combustion chemically combines with the carbon di-oxide as
and when the latter is produced in the fire and is thereby transformed from
an oxide to a carbonate of calcium which is precipitated as ash or unconsumable
residium and falls to the bottom of the grate or fire. From the foregoing it will be
understood that the lime in the fuel produces ash or residium in addition to the
calcareous deposit usually produced from the combustion of ordinary fuel, and thus
increases the quantity of the ash produced from the fuel. To restrict the ash to
the lowest possible quantity compatible with the absorption of all or practically all
the smoke forming products of combustion, we have found that not more than

page_text: ten per cent. of hydraulic lime should in any case be used in the composition of the
fuel, the quantities which we prefer to use being within the limits of from six to
ten per cent. of the total weight of the fuel. The rock or other salt or sulphate of
soda is simply used for the purpose of causing the lime to set or harden quickly and
is well known and commonly used for this purpose. When combined with
substances of a close compact texture such as anthracite coal, peat, or lignite, the
cellulose from its cellular structure affords the air spaces necessary to support com-
bustion, so that these substances when combined with cellulose, may be burnt under
ordinary atmospheric conditions, instead of under forced or induced draught, as is
usually the case. It also deflagrates during combustion and supplies the flame
necessary to the proper burning of the fuel. The cellulose furthermore serves to
bind the particles together during the combustion and to prevent the fuel from
decrepitating or hopping out of the grate, and the consequent crumbling away
of the fuel before it is properly consumed. With ordinary small coal or coal dust,
breeze, charcoal, coke and such like materials of a loose or open texture, cellulose
is not required; the only ingredients being coal dust, hydraulic lime and salt in
about the following proportions :-
Sometimes we use pitch or other bituminous or gummy substance with carbon-
aceous materials, such as ordinary coal dust, for the purpose of holding or binding
the ingredients of the fuel together and causing the particles thereof to cohere
during the process of combustion, but we never use more than about five per cent.
of the whole mass, as the pitch during combustion gives off vapours of a disagreeable
odour. When making artificial fuel in this manner, we add the pitch, the coal dust,
and the lime, together in a dry state, the lime having been slaked about 24 hours
previously all the ingredients are then ground together and steam heated to melt
the pitch, causing it to bind, and the fuel is then pressed to shape. In this method
of manufacture the pitch forms the binding material while the lime is used only in
sufficient quantity to reduce the smoke given off during combustion and to preserve
the blocks when exposed to the weather.
;
We are aware that a compound of coal dust and lime has already been used for the
production of artificial fuel, but so far as we know it has hitherto always been used in
the proportion of from one quarter to one tenth of the whole bulk, and the large
amount of ash or unconsumable residium resulting from the combustion of this fuel
has been a great disadvantage. We therefore shall make no claim broadly to the
combination of lime with coal dust, but shall restrict ourselves to such combination
when the lime is in the proportion of not more than ten per cent. of the whole
mass.
Having now particularly described and ascertained the nature of our said inven-
tion, and in what manner the same is to be performed, we declare that what we
claim is :-
1. Artificial fuel manufactured from anthracite coal dust or other compact
carbonaceous material, cellulose, and hydraulic lime, combined in about the
proportions and for the purposes herein described.
2. The use in the manner and for the purposes stated of the compound of anthra-
cite coal dust or other compact carbonaceous material, cellulose and hydraulic lime
in about the proportions stated.

page_text: 3. Artificial fuel manufactured from coal dust, breeze, and such like materials
of a loose or open texture, hydraulic lime and salt with or without the addition
of a small quantity of pitch combined in about the proportions and for the purposes
herein described.
4. The use in the manner and for the purposes stated, of the compound of
ordinary coal dust or other loose or open carbonaceous material and hydraulic
lime in the proportion of not more than ten per cent. of the whole mass substantially
as described.
Dated this 20th day of my
1032
F. W. GOLBY,
36, Chancery Lane, London, W.C., Patent Agent for the Applicants.