IMPROVE- MENTS IN THE MODE OF UTILIZING THE PRODUCTS OF DISTILLATION OF COM- BUSTIBLE VEGETABLE AND ANIMAL MATTERS IN THE PRODUCTION OF GAS."
Year: 1873

page_text: LETTERS PATENT to David Clovis Knab, Chemist, of St. Denis, in
the Department of the Seine, France, for the Invention of "IMPROVE-
MENTS IN THE MODE OF UTILIZING THE PRODUCTS OF DISTILLATION OF COM-
BUSTIBLE VEGETABLE AND ANIMAL MATTERS IN THE PRODUCTION OF GAS."

page_text: :
employed in the usual mode of distillation for the production of gas
into ammonia, the acetic acid and tar entirely disappearing, the result
being that a highly rich combustible gas is produced eminently adapted
for heating at high temperatures, as the gas produced by my process
consists almost entirely of pure hydrogen, carbonic oxyd, and other
combustible gases in variable proportions, and giving a heating power
22 to 3 times greater than gas burned under the same conditions and
arising from the transformation of coal into carbonic oxyd by air. This
latter gas contains from 60 to 64 per cent. of azote, the presence of
which weakens its combustion, and lessens its heating power.
By the ordinary modes of distillation, where from 250 to 300 cubic
mètres of gas are obtained, by my process from 1500 to 1800 cubic
mètres and more are the result; the effect of converting all the azote
that can be obtained in the form of fixed ammoniacal salts and sub-
jecting it to sulphuric acid or chlorhydric acid for transforming it into
ammonia, the combustible substance is intimately mixed with slacked
lime and the whole is then distilled.
When turf is the substance employed 200 parts at least of slacked
lime is required for every 100 part in weight of turf or peat. Distil-
lation is effected by the ordinary means, but as the matter is pulverous
vertical blast furnaces heated externally can be employed in lieu of the
ordinary retorts or horizontal gas furnaces, so that by my process the
operation is continuous instead of intermittent as is the case by the old
method. The water contained in the turf or peat serves to hydrate the
lime without adding fresh water.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said David Clovis Knab in the Great Seal Patent
Office on the 17th January 1874.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, DAVID
CLOVIS KNAB, Chemist, of St. Denis, in the Department of the Seine, 3
France, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Nineteenth day of July, in the year of
our Lord One thousand eight hundred and seventy-three, in the thirty-

page_text: sixth year
of Her reign, did, for Herself, Her heirs and successors, give
and grant unto me, the said David Clovis Knab, Her special licence
that I, the said David Clovis Knab, my executors, administrators,
and assigns, or such others as I, the said David Clovis Knab,
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 MODE OF UTILIZING THE PRODUCTS OF DISTILLATION OF
COMBUSTIBLE VEGETABLE AND ANIMAL MATTERS IN THE PRODUCTION OF GAS,"
upon the condition (amongst others) that I, the said David Colvis
Knab, 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 Patent.
NOW KNOW YE, that I, the said David Clovis Knab, do hereby
declare the nature of my said Invention, and in what manner the same
is to be performed, to be particularly described and ascertained in
and by the following statement :-
The object of this Invention is to convert into gas all the organic matters
of the vegetable and animal kingdoms, with the exception of the fixed
part forming the ashes; this is effected by distillation either in an open or
closed vessel and mixed with a certain quantity of alkalies or alkaline
carbonates. The gases thus obtained are of three kinds, namely :-
1st. Ammoniacal, which can be transformed into ammoniacal salts.
2nd. Hydrogen,
3rd. Carbonic oxyd, }
which are suitable for lighting and heating.
According to the nature of the matter to be treated and its richness
in azote, so the opperations are conducted in such a manner as specially
to extract therefrom one or more of these gases, and more particularly
to make either ammoniacal salts, lighting or heating gas, or to produce
them simultaneously.
Manufacture of Ammoniacal Salts.-If the substance is rich in azote,
it is distilled in a closed vessel with once or twice its weight of an alkali

page_text: (slaked lime or soda for instance). The products of distillation are
condensed and the gases washed in suchwise as to retain all the ammo-
niacal gas produced by the combination of the azote with the hydrogen
arising from the decomposition of the water of combination of the
alkali. The ammoniacal liquors are then saturated with an acid and
after crystallization are sold in the form of ammoniacal salts. In this
case the two other gases are only useful for heating and may serve as
combustibles in the operation, unless the hydrogen is carbureted by the
known process to convert it into a lighting gas. It is in this manner
that waste wool, animal matters, and turf rich in azote should be
treated.
Manufacture of Lighting Gas.-In making lighting gas a retort is
charged as usual with coal, and at the same time is introduced, either in
a recipient of some sort or a partitioned part of the retort, a mixture of
coal, turf, and so on, and alkali, lime, and soda. .The weight of the
coal and turf is from 2 to 6 per cent. of that of the ordinary charge.
This matter is pulverized or crushed with an equal quantity of alkali,
lime for instance. The hydrogen liberated from this mixture borne to
a red heat finds itself in its primitive state in presence of the over
heated vapours of the tar arising from the ordinary charge of coal,
becomes carbureted, and increases the lighting gas produced 30 to 40
per cent. The ammonia produced from the whole of the azote con-
tained in the number of kilogrammes of matter treated by the alkali is
collected with that furnishing the usual charge.
If lime is used as alkali, and that a little soiling of the coke is not
minded, it is not necessary to introduce the mixture in powder in a special
recipient; it can be put in with the charge itself, or little, brick shaped
cakes or balls previously prepared in the requisite proportions can be
employed. The coke produced can be burned in the works.
It should be understood that as the case may require so the process is
applied to one or all the retorts in the works by treating them with an
alkali to a part or the whole charge.
Manufacture of Heating Gas.-In making heating gas the same
operation as the preceding is employed by operating in a furnace or
retort by therein distilling coal, turf, and schiste, with an equal quantity
of alkali, soda, and lime, carbonate of lime, which by heat is quickly
transformed into lime. The little ammonia produced may, if desired,