IMPROVEMENTS IN THE MANUFACTURE OF GAS AND FUEL
Year: 1874

page_text: LETTERS PATENT to Alexander Melville Clark, of 53, Chancery Lane,
in the County of Middlesex, Patent Agent, for the Invention of
"IMPROVEMENTS IN THE MANUFACTURE OF GAS AND FUEL."-A com-
munication from abroad by La Société Universelle de Fabrication
de Produits propres à l'Éclairage et au Chauffage, represented by
Charles Jenty, of Paris, France.
PROVISIONAL SPECIFICATION left by the said Alexander Melville
Clark at the Office of the Commissioners of Patents, with his
Petition, on the 30th June 1874.
I, ALEXANDER MELVILLE CLARK, of 53, Chancery Lane, in the
County of Middlesex, Patent Agent, do hereby declare the nature of
the said Invention for "IMPROVEMENTS IN THE MANUFACTURE OF GAS AND
FUEL," to be as follows:-
This Invention relates to the employment in the manufacture of rich
gas for illuminating and heating purposes of napthaline (C20 H 8) and
its congeners, prepared as hereafter described.

page_text: Napthaline has not hitherto been applied for the manufacture of gas
on a commercial scale, and in order to do so it is first necessary to
find some liquid hydrocarbon rich in hydrogen and capable of being
decomposed at the same degree of heat as napthaline itself, in order
that I may proceed by causing this mixture of hydrocarbon to be
absorbed by a porous body, which on being decomposed will itself
yield proto-carburetted hydrogen. To this end I proceed as follows:-
I prepare a liquid carburet of hydrogen from heavy petroleum oil or
other hydrocarbon which will be decomposed at the same temperature
as napthaline. For this purpose I take crude napthaline obtained from
heavy gas oils and heat it from 100° to 120 degrees Fahrenheit, in
order to liquefy the same, and I then add, according to the richness
of the gas to be produced, from 5 to 20 or 25 per cent. by weight of
prepared petroleum oil or other hydrocarbon decomposing at the same
temperature as napthaline. The following are examples of the com-
position:--

page_text: I immerse in one or other of these baths heated to from 100 to 120
degrees Fahrenheit peat or other dried and prepared porous body
capable of yielding proto-carburetted hydrogen. This porous substance
is caused to imbibe from 12 to 14 per cent. of the prepared napthaline,
which may be effected either by immersion as above mentioned, or by
injection under pressure. In this condition the peat or other product
carburetted as described will yield in ordinary gas apparatus from
13,000 to 14,000 cubic feet of rich gas per ton in addition to from
5 to 6 hundredweight of carbonized peat coke. The gas produced will
possess an illuminating power of 7 to 24 candles, according to the
composition of the bath employed supplied at the rate of 23 gallons
per hour.
Peat carburetted as above described will give excellent results when
used alone, but in order to obtain a product adapted for the production
of gas and to replace the cannel coal and boghead used to enrich
common coal gas which produce little if any coke, I take peat car-
buretted in one of the baths herein-before mentioned in the proportion
of from 60 to 70 parts by weight, good gas coal 30 to 40 parts, and lime
one part; these proportions may however be varied. The matters are
ground up together with 10 to 12 per cent. of a mixture of coal and
wood tar and afterwards compressed and moulded into blocks of any
suitable form. One ton of this material will produce from 14,000 to
15,000 cubic feet of gas of 18 to 20 candle power, with an expenditure
of 23 gallons per hour, in addition to half a ton of vegeto-mineral coke,
which owing to its porosity and the nature of its composition will form
a perfect substitute for all kinds of domestic fuel.
0
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Alexander Melville Clark in the Great Seal Patent
Office on the 29th December 1874.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, ALEXANDER
MELVILLE CLARK, of 53, Chancery Lane, in the County of Middlesex,
Patent Agent, send greeting...
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Thirtieth day of June, in the year of our

page_text: Lord One thousand eight hundred and seventy-four, in the thirty-eighth
year of Her reign, did, for Herself, Her heirs and successors, give
and grant unto me, the said Alexander Melville Clark, Her special
licence that I, the said Alexander Melville Clark, my executors, admini-
strators, and assigns, or such others as I, the said Alexander Melville
Clark, my executors, administrators, and assigns, should at any time agree
with, and no others, from time to time and at all times thereafter
during the term therein expressed, should and lawfully might make,
use, exercise, and vend, within the United Kingdom of Great Britain
and Ireland, the Channel Islands, and Isle of Man, an Invention for
"IMPROVEMENTS IN THE MANUFACTURE OF GAS AND FUEL," a communication
to me from abroad by La Société Universelle de Fabrication de Produits
propres à l'Éclairage et au Chauffage, represented by Charles Jenty, of
Paris, France, upon the condition (amongst others) that I, the said
Alexander Melville Clark, my executors or administrators, by an
instrument in writing under my, or their, or one of their hands and
seals, should particularly describe and ascertain the nature of the said
Invention, and in what manner the same was to be performed, and
cause the same to be filed in the Great Seal Patent Office within six
calendar months next and immediately after the date of the said Letters

page_text: naphthaline, obtained from heavy gas oils, and heat it to from 100° to
120 degrees Fahrenheit in order to liquefy the same, and I then add,
according to the richness of the gas to be produced, from 5 to 20 or 25
per cent. by weight of prepared petroleum oil or other hydrocarbon
decomposing at the same temperature as naphthaline. The following
are examples of the composition :-
I immerse in one or other of these baths, heated to from 100 to 100
degrees Fahrenheit, peat or other dried and prepared porous body capable
of yielding proto-carburetted hydrogen. This porous substance is caused
to imbibe from 1 to 14 per cent. of the prepared naphthaline, which
may be effected either by immersion, as above mentioned, or under
pressure. In this condition the peat or product carburetted as described
will yield in ordinary gas apparatus from 13,000 to 14,000 cubic feet of
rich gas per ton, in addition to from 5 to 6 hundredweight of carbonized
peat coke.
The gas produced, possessing according to the compo-

page_text: sition of the bath employed an illuminating power of 7 to 24 candles
with a consumption of 3.7 cubic feet of gas per hour.
Peat carburetted as above described will give excellent results when
used alone, but in order to obtain a product adapted for the production
of gas, and to replace the cannel coal and boghead used to enrich
common coal gas, which produces little if any coke, I take peat
carburetted in one of the baths herein-before mentioned in the propor-
tion of from 60 to 70 parts by weight, good gas coal 30 to 40 parts, and
lime one part. These proportions may however be varied. The matters
are ground up together with 10 to 12 per cent. of a mixture of coal and
wood tar, and afterwards compressed and moulded into blocks of any
suitable form. One ton of this material will produce from 14,000 to
15,000 cubic feet of gas of 18 to 20 candle power, with an expenditure
of 3.7 cubic feet of gas per hour, in addition to half a ton of vegeto-
mineral coke, which owing to its porosity and the nature of its
composition will form a perfect substitute for all kinds of domestic
fuel.
The production of hydrogen gas by the decomposition of water and
its employment in the manufacture of illuminating gas is a fact well
known in gas making, but this mode of producing hydrogen necessitates
the employment of a steam generator and superheater, provided with
substances capable of retaining the oxygen and setting free the hydrogen.
This apparatus is additional to that ordinarily employed for generating
gas, and thus increases the cost to such an extent as to preclude its uso
in small works.
The study of the use of peat for the purposes of gas making has led
to the discovery of a means of producing proto-carburetted hydrogen
gas without expense, and even advantageously, and of utilizing the same
in distilling coal and other gas producing substances. By this process
not only is additional apparatus dispensed with, but a profit is realized
in the production of hydrogen, which may be utilized in the manufacture
of gas. Two methods of obtaining this result may be employed.
According to the first method suitable proportions of gas coal and
ordinary peat, well dried, are mixed together in a fincly pulverized
condition; for example, 60 parts by weight of gas coal and 40 parts of
peat; together, 100 parts.

page_text: The retort heated to the ordinary temperature is charged with this
mixture, by the decomposition of which the following effects are pro-
duced-The excess of carbon of the volatile hydrocarbons evolved from
the coal combines with the proto-carburetted hydrogen from the peat
which is mixed with the coal, and forming therewith bicarburetted
hydrogen C, H*. In this manner 945 cubic feet of gas have been
obtained from 220 lbs. of coal, giving an illuminating power equal to 7
candles with a consumption of 3.7 cubic feet of gas per hour. This coal
contained from 90 to 92 parts of carbon and only 5 of hydrogen, the
latter being evidently in too small a proportion to produce a larger
quantity of gas. By mixing however 60 parts by weight of the same
coal with 40 parts of dried peat, both in a pulverized condition, 1220
cubic feet of gas of 8 candle power, with the same expenditure per hour,
has been obtained. Hence it is evident that the proto-carburetted
3 hydrogen from the peat becomes carburetted in a nascent state at the
expense of a certain quantity of carbon vapors in excess resulting from
the coal and its hydrocarbons undergoing decomposition. The process
is rendered still more economical, inasmuch as the residue in the retorts
is formed of porous coke, which is readily combustible, and which I
designate as vegeto-mineral coke.
By observing the effects of distilling a mixture of coal and dried peat
the inventors have been led to include that the proto-carburetted
hydrogen from the peat may be utilized either by mixing the same with
rich gas for the purpose of augmenting the product obtained from gas
coal, or from peat carburetted with naphthaline.
"
The following in brief is the mode of operation, constituting what I
term the first method:- I take gas coal, known in France as "Courrière'
coal, for example, and when it is brought to a state of decomposition
introduce proto-carburetted hydrogen produced by the decomposition
of dried peat, by which means a much larger quantity of gas is obtained
of the same illuminating power, which fact is another proof that the
proto-carburetted hydrogen is carburetted at the expense of the carbon
vapors in excess, and of the hydrocarbons contained in the coal. By
thus adding gas from dried peat to the coal in a state of decomposition,
that is to say, by introducing peat gas into the retorts containing the
coal under distillation, and before the gas enters the hydraulic main,
the proto-carburetted hydrogen C², H*, resulting from the decomposition

page_text: of the peat, passes into the state of bicarburetted hydrogen C+, H*, by
being carburetted with the excess of carbon contained in a nascent state
in the naphthaline. By this means from 28,000 to 35,000 cubic feet of
gas may be obtained from one ton of gas coal, the carbon vapors con-
tained in the coal being more than sufficient for carburetting 28,000
cubic feet of proto-carburetted hydrogen.
I will now proceed to describe a process of steeping, injecting, or
impregnating peat with prepared naphthaline, suitable for producing a
gas of the kind herein-before referred to. The details given are
necessary in order that the value of this method of treatment may be
clearly understood. I put 220 lbs. of gas tar into a retort and distil the
same as follows:-I commence by distilling slowly at a low temperature in
order to eliminate the benzine, forming about 6 per cent. of the weight
of the tar, which passes over at a temperature of from 176° to 250 degrees
Fahrenheit. The distillation is then continued at a higher temperature
to obtain the heavy oils and naphthaline, forming about 30 per cent. of
the composition of the tar. The pitchy residue remaining in the retort
is then withdrawn, and the operation recommenced.
The following shows the commercial results of distilling 220 lbs. of
A net profit of 11/1/2 is thus obtained without reckoning the 66 lbs. of
mixture of heavy oil and naphthaline which are separated by means of a
turbine after the napkthaline has been allowed to crystallize. After the a
naphthaline is separated from the heavy oil a separate bath of one or
the other of these two matters is prepared, to be used for carburetting
the peat.

page_text: of
For example, a bath for the manufacture of rich gas may be composed
This mixture is heated to from 104° to 122° Fahrenheit, and the peat
then immersed therein after being dried and prepared in condition to
absorb 14 or 15 per cent. of the said mixture.
Although when treating tar the heavy oils and naphthaline cost
nothing I reckon their commercial value at 3*/2ª per 220 lbs., thus,―
By impregnating one ton of peat with 15 per cent. of this bath
(330 lbs.) costing 6/- a ton, 330 lbs. of material is obtained suited for
25 which gives for 1 ton of carburetted peat for producing rich gas of 24
candle power 16/9.6. The products obtained per ton of material
d.
costing 16,, 96 are 14,000 cubic feet of rich gas of from 23 to 24 candle
power at an expenditure of 37 cubic feet per hour, which represents an
illuminating power three times greater than that of ordinary gas.

page_text: 2000
From which must be deducted the value of
the material
Leaving a net profit of
£6 9 6
1
5 4
£5 4 2
I may also produce ordinary quality gas from peat carburetted for
rich gas.
In order to obtain by this improved process a gas of a quality
equivalent only to that of coal gas, that is to say gas of 7 candle power,
with a consumption of 3-7 cubic feet per hour, I proceed in the following
manner-I take 44 lbs. of peat prepared for obtaining rich gas and
60 lbs. of ordinary dried peat, and charge a retort with this mixture
from which I obtain the same amount of gas as though the whole had
been carburetted, but with this difference, that the gas does not possess
the small illuminating power, being only of from 7 to 8 candle power,
with a consumption of 3-7 cubic feet per hour. This is explained by the
fact that the hydrogen set free by the decomposition of the ordinary
unprepared peat becomes in its nascent state carburetted at the expense
of the carbon vapors produced by the decomposition of the peat prepared
for rich gas. It will be observed that in this latter operation the expense
of carburetting is in respect only of the 44 lbs. of prepared peat, that is
to say from 3/- to 4/- per ton instead of 9/7d. The result of this latter
experiment with carburetted peat mixed with ordinary peat proves that
the constituent elements of coal gas as well as of other gases employed
for illuminating purposes may be divided into two classes, viz., the
luminous and non-luminous elements. In the first class may be ranged
olefiant gas and hydrocarbons, and in the latter hydrogen and oxide of
carbon, and more particularly proto-carburetted hydrogen. The former
class furnishes the gaseous elements which produce light, but at least

page_text: one of the gases of the second class is indispensable, as otherwise the
combustion of the hydrocarbons could be obtained with difficulty without
producing smoke and consequent loss of light.
All the elements of the first class instantly decompose at a high
temperature and deposit their carbon in very minute particles, which
form as many contres of radiation of the light in a gas flame, and the
greater the number of these particles present in the flame the greater is
the amount of light emitted. Thus it is evident that the value of these
hydrocarbons as luminous agents is proportionate to the quantity of
carbon which they contain for a given volume. Hence the gases and
vapors of the first class which are most dense have therefore the highest
illuminating properties. All the elements of this class are, as above
mentioned, more or less rapidly decomposed at a red heat, and in the
ordinary processes of manufacture the inside of the retort soon becomes
coated with a layer of carbon from this cause. This decomposition of
the illuminating element of the gas depends in the first place on the
time during which they remain exposed to a high temperature, and in
the second place on the number of particles of these elements which
are brought in contact with the heated surface of the retort. Two
methods of preventing this decomposition may be employed, one of
which consists in the rapid withdrawal of the gas from the retort, while
the other consists in mixing the non-luminiferous elements with the
illuminating gases, as it is evident that the number of atoms of
illuminating gas brought into contact with a given surface would be
reduced one half if it be mixed with an equal volume of hydrogen.
Both the above methods are combined in the improved manufacture
of rich gas from naphthaline and its congeners forming the subject of
the present Invention. The results obtained in practice have clearly
shown the correctness of the principles above stated. The commercial
value of this process, however, depends on the cost price of the proto-
carburetted hydrogen as compared with that of ordinary gas, and it has
been shown from the foregoing that the carbon vapors and hydrogen
may be obtained almost without any expense, the latter by the decom-
position of peat and the former from naphthaline.
Having described the nature of the Invention and the manner of 3
performing the same, I declare that what I claim as the Invention to be
protected by the herein-before in part recited Letters Patent is, the novel

page_text: use or application of naphthaline prepared as specified (or of any other
matter containing naphthaline or from which naphthaline may be
produced) in the manufacture of gas for illuminating and heating
purposes and fuel for domestic use, substantially as described.
In witness whereof, I, the said Alexander Melville Clark, have
hereunto set my hand and seal, this Twenty-ninth day of
December, in the year of our Lord One thousand eight hundred
and seventy-four.