AN IMPROVED PROCESS FOR TREATING SEA-WRACK OR OTHER MARINE PLANTS
Year: 1875

page_text: LETTERS PATENT to Hector Auguste Dufrené, of No. 10, Rue de la
Fidélité, Paris, in the Republic of France, and 4, South Street,
Finsbury, London, Civil Engineer and Patent Agent, for the
Invention of "AN IMPROVED PROCESS FOR TREATING SEA-WRACK OR OTHER
MARINE PLANTS."-A communication from Messieurs Glaizot Frères,
of Ahon-weak Finistère in the Bonublic of France
PROVISIONAL SPECIFICATION left by the said Hector Auguste Dufrené
at the Office of the Commissioners of Patents, with his Petition,
on the 11th August 1875.
I, HECTOR AUGUSTE DUFRENÉ, of No. 10, Rue de la Fidélité, Paris,
in the Republic of France, and 4, South Street, Finsbury, London,
Civil Engineer and Patent Agent, do hereby declare the nature of
the said Invention for "AN IMPROVED PROCESS FOR TREATING SEA-WRACK OR
OTHER MARINE PLANTS," to be as follows, that is to say:—
In carrying out this Invention dry sea-wrack is placed in a furnace
in thick layers, and is lighted at the lower part. It burns from the

page_text: effect of a current of cold or hot air forced in by means of suitable
tuyeres from a blowing machinc. The gases in passing through the
upper layers distil them, and the vapours given off are then condensed
in suitable known apparatus. The combustible gases are then burnt so
as to furnish a certain amount of heat which can be utilized.
I prefer employing a vertically placed furnace elliptical in horizontal
section, widened out at the upper part and furnished with tuyeres at its
lower part. The mouth of the furnace is so constructed as to close
hermetically. I can add to the furnace horizontal chambers where the
sea-wrack is charged.
The ash of the sea-wrack reduced to a doughy state falls into fixed or
moveable crucibles or pots, from which it is extracted to withdraw the
soda, iodine, and other resulting products.
If the sea-wrack is green it should be first dried. For this purpose
the heat developed from the combustion of the gases coming from the
herein before described furnace is employed.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Hector Auguste Dufrené in the Great Seal Patent
Office on the 9th February 1876.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, HECTOR
AUGUSTE DUFRENÉ, of No. 10, Rue de la Fidélité, Paris, in the Republic
of France, and 4, South Street, Finsbury, London, Civil Engineer and
Patent Agent, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Eleventh day of August, in the year
of our Lord One thousand eight hundred and seventy-five, in the thirty-
eighth year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said Hector Auguste Dufrené, Her special
licence that I, the said Hector Auguste Dufrené, my executors, admini-
strators, and assigns, or such others as I, the said Hector Auguste
Dufrené, my executors, administrators, and assigns, should at any time
agree with, and no others, from time to time and at all times there-

page_text: after 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 In-
vention for "AN IMPROVED PROCESS FOR TREATING SEA-WRACK OR OTHER
MARINE PLANTS," a communication from Messieurs Glaizot Frères, of
Aber-wrack, Finistère, in the Republic of France, upon the con-
dition (amongst others) that I, the said Hector Auguste Dufrené,
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 Hector Auguste Dufrené, do hereby
declare the nature of the said Invention, and in what manner the same
is to be performed, to be particularly described and ascertained in and
by the following statement, that is to say :—
This Invention consists in distilling or incinerating sea-wrack and
other marine plants.
In carrying out. the Invention sea-wrack dried in the air or otherwise is
placed in any suitable furnace in sufficiently thick layers, and lighted at
the lower part. Air is introduced from any suitable blowing machine
by means of a number of tuyeres proportioned to the surface of the
horizontal section of the bottom; or the current of air may be produced
by a force pump.
The tuyeres are distributed around the bottom in one
or several rows. They may be aided either by means of central tuyeres
throwing the air vertically towards the centre of the mass of sea-wrack,
or by means of a grate or other analogous blowing apparatus formed of
one or several hollow bars placed horizontally and put in communication
at one end with the blower, the other end being closed and pierced on
their upper generatrices with holes provided or not with adjustments and
forming tuyeres. The injected air may be either cold or may be
previously heated by any known process.
The quantity of air injected is regulated by the following conditions:-
All the oxygen of the air introduced should, on contact with the lower
layers of charcoal heated to red heat, be converted into carbonic acid.
This carbonic acid will pass into the state of oxyde of carbon by passing.

page_text: through the upper beds of this charcoal. This conversion of carbonic
acid into oxyde of carbon causes an absorption of heat, which lowers the
temperature of the gases and benefits the subsequent condensation, but
their temperature will remain more than sufficient, and on leaving the
condensing apparatuses the heat absorbed by this fixation of carbon will
be given up by the combustion of the oxyde of carbon produced.
The oxyde of carbon and the nitrogen of the air introduced act by
the heat which they have acquired, and causes the distillation of the
sea-wrack and its carbonization, drawing along the products of this
distillation, then becomes partly cooled by desiccating the upper layers
of the sea-wrack.
The thickness of the bed of sea-wrack is regulated by the following
condition-The gases and the products of the distillation should become
cool on this bed in such a manner as only to present a temperature
lower than two hundred and fifty degrees centigrade. The gases, the
tars, and the other volatile products are, on leaving the furnace, con-
ducted into condensing apparatuses of any suitable form where the
tars are deposited, and nearly all the volatile products drawn off.
It is difficult to completely purify the gases; nearly all the empyreu-
matic and alkaline matters they contain are removed by causing them
to pass through columns of coke or other porous substances soaked with
pure water, or with water acidulated with sulphuric acid, which will fix
the ammonia. These gases, a large portion of which is combustible,
are lighted and completely burnt, thus furnishing a large quantity of
heat.
A good arrangement consists in causing the gases to pass over a grate
charged with incandescent coal or charcoal; a sufficient quantity of air
being introduced in this manner, none of the offensive smelling
particles drawn along. by the gas will escape combustion.

page_text: drawn towards the basin either by hand or by mechanical means, such
as an archimedian screw, endless chains or cloths, or mechanical rakes.
This form presents the advantage of requiring a less powerful pressure
of blast, the sea-wrack taking up less height, and consequently less.
pressed down in the basin.
Thirdly. Reverberatory furnaces fed in a similar manner to those
herein-before described.
The following however is the one which I prefer as being the best for
carrying out the objects proposed. This furnace, which is placed
vertically, is constructed with a basin, the horizontal section of which
is that of an ellipse with its larger axis greatly elongated relatively to
its smaller axis, or even of an elongated rectangle, the small sides of
which can be wholly or partly replaced by arcs of a circle. All these
furnaces may be divided by vertical partitions. The annular section may
also be employed.
The tuyeres are arranged in one or several rows on the periphery of
the furnace, and may be aided by grates or analogous blowing apparatus,
or by means of central tuyeres, as herein-before described.
The basin widens from the bottom towards the top up to the upper
part, where the carbonization takes place in order that the mass of sea-
wrack, which in desiccating and carbonising contracts considerably,.
shall constantly apply itself against the walls of the furnace and prevent
the air escaping lengthwise from the walls.
The openings for collecting the gas will be centrally placed, or may be
at the periphery.
The mouth of the furnace provided with a hydraulic or other closing
should be provided with a mechanism capable of allowing the sca-wrack
to be charged in regular layers without pressing it, and without
interrupting the working of the blast. These furnaces may be put in
communication at their lower part with horizontal furnaces; the
charging then takes place at the extremity of these furnaces, and the
collection of the gas takes place there.
Whatever may be the form of the furnaces, they are terminated at
their lower part by one or several crucibles for receiving the ashes of
the sea-wrack brought to a pasty state by the heat of the combustion..

page_text: These ashes are withdrawn from the crucibles through the working
doors, stirred and pugged while still hot in moveable crucibles, and then
carried on to a cooling floor or into a stove, where their heat is employed
in desiccating the sea-wrack.
I have hitherto confined the description of the improved process as
applicable only for the treatment of sea-wrack previously dried in the
open air. The process is equally applicable to the treatment of a certain
quantity of green sea-wrack added to the dry sea-wrack, but in con-
sequence of the benefit to be derived from the employment of the
products of the distillation I prefer employing (with certain exceptions
determined by local circumstances) the process herein-after described,
which presents the advantage of not condensing with the liquids of
value the large quantities of water resulting from the green sea-wrack
introduced, which water after having been vaporized in the apparatuses
would be condensed, and then in the subsequent treatment would be
carried to the boiling point, and even in certain cases would be
vaporized.
It has been shown that heat has been produced in excess, and it is
preferable under the ordinary conditions to employ it for drying green
sea-wrack in stoves or other apparatuses annexed, allowing the evapo-
rated water to be thrown off into the atmosphere. It would be the
same for the gases produced by the interior or exterior heating if
connected with the apparatuses. These gases could be introduced into
the furnaces, but it is preferable to employ them for heating the annexed.
apparatuses, because those inert gases mixed with the partly combustible
gases resulting from the distillation would be prejudicial to the com-
bustion of the latter.

page_text: When local circumstances are not conducive to the utilisation of the
products of the condensation, the tuyeres or the blast grates herein-
before described, as well as the employment of hot air, allow of the
burning of the green sea-wrack in furnaces of all forms followed or not
by horizontal chambers. The furnaces of elongated section, with or
without horizontal chambers, are admirably adapted for this operation.
In this case the tuyeres are arranged and the blast regulated in such a
manner as to burn as completely as possible the gases in the interior of
the furnace, thus utilizing them as much as possible in the production
of heat. Means for heating the furnaces internally or externally may
be added also for forcing into the mass the gases resulting from the
combustion for charging dry sea-wrack with the green sea-wrack, or for
charging alternately layers of green sea-wrack with thin layers of coal
in suitable proportions.
1
Having thus described the nature of the Invention communicated to.
me, and the best means with which I am acquainted for carrying the
same into effect, what I claim is,—
Firstly. The distillation of sea-wrack or other marine plants in a
current of, oxyde of carbon, or (which is not so good) of carbonic acid,
produced by the combustion of the carbon of the sea-wrack introduced
into the apparatus, as herein-before described.
Secondly. The employment of this distillation of cold and hot air
introduced by one or several rows of small tuyeres, by central tuyeres,
or by blast grates, or any analogous blowing apparatus, or by a com-
bination of these different tuyeres.
Thirdly. The regulation of the blast in such a manner as only to
introduce the minimum quantity of air to burn only the carbon in the
furnace to the exclusion of the products of distillation, the latter being
collected and the others which are combustible but not condensable,
being burnt only on leaving the condensing apparatuses either directly
or by means of a grate charged with charcoal, as herein-before
described.
Fourthly. The employment of all forms of furnaces possessing the
required features for the distillation, and particularly furnaces of an
elongated elliptical section or of an elongated rectangular section, the
small sides of which may be wholly or partially replaced by arcs of a

page_text: H. A. DUFRENÉ. (L.S.)