Improvements in the Method of and Apparatus for Retting or Steeping Flax.
Year: 1899

page_text: Date of Applicati
4000
(in United Kingdom), 19th Oct., 1999
Complete Specification Left, 19th July, 1900-Accepted, 19th Nov., 1900
Date of Application
Complete Specification Left, 19th July, 1900-Accepted, 19th Nov.,
1900
Improvements in the Method of and Apparatus for Retting or Steeping
Flax.
I, ANTOINE BADOIL, of 2, Rue Glandeyès, Marseille, in the Republic of France,
Chemical Engineer, do hereby declare the nature of this invention to be as
follows:-
My improved process of chemically retting or steeping flax consists in the
employment, in combination, of soap and acids (preferably hydrochloric acid) in
an apparatus of special construction.
Soap has the property of disaggregating the substances which envelope the fibre
and of facilitating their solution in water; as a consequence the peel or bark is
separated and swells by the action of the soapy water. But the soap, having
the disadvantage of adhering to the fibre and thus rendering it sticky, impedes
the subsequent operations; it is therefore indispensible, when the soap has accom-
plished its purpose, to neutralise it; to this end I employ hydrochloric acid which
whilst decomposing the soap and removing it from the base, renders the fibre
whiter and the peel or bark more brittle.
--
In the accompanying drawing, have shown, as an example only, how my
said invention can be conveniently and advantageously carried into practice :-
Figure 1 is a vertical section and
Figure 2 a plan of the apparatus employed in my improved process.
This apparatus comprises a series of rats or tanks a, arranged side by side, each
divided into several compartments by means of cross-pieces arranged in longitu-
dinal and transverse directions, each division having four grooves intended to
receive the four frame pieces of a cage. To each of the said frame pieces, grid
plates b, placed one above the other, are fixed by means of removable linch pins
or cottars. The upper-most plate of each cage, which plate receives and transmits
pressure, is made solid or is reinforced by strengthening ribs. The frame pieces
are united at their upper parts by tie-rods. At its upper part, the tank is closed.
by a lid which can be closed hermetically, and at its lower part is formed a
receiving vessel or basin provided with an escape orifice.
The flax-stalks, tied in bundles, are placed on the various grid plates 6 and
compressed; the con.pression by itself can have no deleterious effect on the fibre,

page_text: it rather tends to create a kind of capillarity. The bundles of stalks, such as
are brought to the factory, are placed in such a manner that their ends may be
within. The dry flax displaces a large volume of water of which it absorbs four
times its weight and, by settlement, the space which it occupies, after compression,
is reduced about two thirds.
The stalks of flax are placed together with a quantity of soap, in the proportion
of eight kilogrammes of soap to one hundred kilogrammes of flax stalks, in the
tank a which is then filled up with tepid water. In this bath, which is kept at a
temperature of from 70 to 80 degrees Centigrade, the stalks remain for about two
hours.
The flax stalks are afterwards removed from the bath and passed between fluted
rollers in order to separate the peel from the fibres and to express the absorbed
liquid.
To afterwards cleanse the fibres from the soap which adheres thereto, some acid,
preferably hydrochloric acid, is added to the 'soapy bath in the proportion of three
litres of hydrochloric acid diluted in thirty litres of water for each one hundred
kilogrammes of flax stalks. The stalks remain immersed for about one hour in
this second or acid bath which is kept at a temperature of about sixty degrees
Centigrade. Instead of adding the acid to the bath of soapy water the latter
can be run off and a new bath, made up of hydrochloric acid diluted in the above
mentioned proportions, poured in.
The liquid is afterwards run off and the flax freed from acid adhering thereto
by washing the stalks with warm water and leaving them to drain.
The tank is again emptied and filled with chlorinated water prepared by mixing
ien kilogrammes of chloride of lime and ten kilogrammes of carbonate of soda in
a thousand litres of water; the stalks then remain immersed for about three hours
in this bath which is kept at a temperature of about 30 degrees Centigrade.
The chlorinated water is afterwards drawn off and a strong jet of water directed
into the tank to remove the chlorine from the fibres.
The tank a is provided with an autoclave or digester-lid.
During the duration of the boil, a subsidence is produced which renders the
desiccation of the stalks which are at the centre, difficult. To obviate this fault
and to dry the flax, I employ a hydro-extractor operating similarly to those used in
the manufacture of beet-root sugar; a speed of 500 revolutions per minute would
be sufficient (obviously with the option of increasing or decreasing this speed as
desired). After desiccation, the flax is placed in a stove or drying room, before
passing to the stripping knife.
My improved process of chemical retting or steeping flax therefore requires,
per ton (metrical) of flax, 80 kilogrammes of soap and 30 litres of hydrochloric
acid. By this improved process is obtained flax of a superior quality to that
obtained by former processes in which, the fermentation varying according to the
temperature, the stalks which are in the centre of the bundles are decomposed first
and will be subjected to a more energètic decomposition than the stalks upon the
outsides of the bundles in such a manner that retting or steeping is irregular.
By my improved process, on the contrary, a regular and homogeneous retting
or steeping is obtained.
The cost of drying, in my improved process is appreciably less, than in the
processes hitherto employed, the manufacture is no longer at the mercy of change
in the weather; there is no waste; moreover, the whole of the work can be carried
on throughout the year without interruption.
My improved process, moreover, permits the recovery of lignin and other bye-
products contained in the stalk of flax.
Dated this 10th dor of October 1800
D. YOUNG & Co.,
11 & 12, Southampton Buildings, London, W.C.,
Agents for the Applicant.

page_text: COMPLETE SPECIFICATION.
Improvements in the Method of and Apparatus for Retting or Steeping
Flax.
I, ANTOINE BADOIL, of 2, Rue Glandevès, Marseille, in the Republic of France,
Chemical Engineer, 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:―
My improved process of chemically retting or steeping flax consists in the
employment, in combination, of soap and acids (preferably hydrochloric acid) in
an apparatus of special construction.
Soap has the property of disaggregating the substances which envelope the fibre
and of facilitating their solution in water; as a consequence the peel or bark is
separated and swells by the action of the soapy water. But the soap, having
the disadvantage of adhering to the fibre and thus rendering it sticky, impedes
the subsequent operations; it is therefore indispensible, when the soap has accom-
plished its purpose, to neutralise it; to this end I employ hydrochloric acid which
whilst decomposing the soap and removing it from the base, renders the fibre
whiter and the peel or bark more brittle.
In the drawing left with my Provisional Specification, I have shown, as an
example only, how my said invention can be conveniently and advantageously
carried into practice:
-
Figure 1 is a vertical section and
Figure 2 a plan of the apparatus employed in my improved process.
This apparatus comprises a series of vats or tanks a, arranged side by side, each
divided into several compartments by means of cross-pieces arranged in longitu-
dinal and transverse directions, each division having four grooves intended to
receive the four frame pieces of a cage. To each of the said frame pieces, grid
plates b, placed one above the other, are fixed by means of removable linch pins
or cottars. The uppermost plate of each cage, which plate receives and transmits
pressure, is made solid or is reinforced by strengthening ribs. The frame pieces
are united at their upper parts by tie-rods. At its upper part, the tank is closed
by a lid which can be closed hermetically, and at its lower part is formed a
receiving vessel or basin provided with an escape orifice.
The flax-stalks, tied in bundles, are placed on the various grid plates band
compressed; the compression by itself can have no deleterious effect on the fibre,
it rather tends to create a kind of capillarity. The bundles of stalks, such as
are brought to the factory, are placed in such a manner that their ends may be
within. The dry flax displaces a large volume of water of which it absorbs four
times its weight and, by settlement, the space which it occupies, after compression,
is reduced about two thirds.
The stalks of flax are placed together with a quantity of soap, in the proportion
of eight kilogrammes of soap to one hundred kilogrammes of flax stalks, in the
tank a which is then filled up with tepid water. In this bath, which is kept at a
temperature of from 70 to 80 degrees Centigrade, the stalks remain for about two
hours.
The flax stalks are afterwards removed from the bath and passed between fluted
rollers in order to separate the peel from the fibres and to express the absorbed
liquid.
To afterwards cleanse the fibres from the soap which adheres thereto, some acid,
preferably hydrochloric acid, is added to the soapy bath in the proportion of three
litres of hydrochloric acid diluted in thirty litres of water for each one hundred

page_text: kilogrammes of flax stalks. The stalks remain immersed for about one hour in
this second or acid bath which is kept at a temperature of about sixty degrees
Centigrade. Instead of adding the acid to the bath of soapy water the latter
can be run off and a new bath, made up of hydrochloric acid diluted in the above
mentioned proportions, poured in.
The liquid is afterwards run off and the flax freed from acid adhering thereto
by washing the stalks with warm water and leaving them to drain.
The tank is again emptied and filled with chlorinated water prepared by mixing
ten kilogrammes of chloride of lime and ten kilogrammes of carbonate of soda in
a thousand litres of water; the stalks then remain immersed for about three hours
in this bath which is kept at a temperature of about 30 degrees Centigrade.
The chlorinated water is afterwards drawn off and a strong jet of water directed
into the tank to remove the chlorine from the fibres.
The tank a is provided with an autoclave or digester-lid.
During the duration of the boil, a subsidence is produced which renders the
desiccation of the stalks which are at the centre, difficult. To obviate this fault
and to dry the flax, I employ a hydro-extractor operating similarly to those used in
the manufacture of beet-root sugar; a speed of 500 revolutions per minute would
be sufficient (obviously with the option of increasing or decreasing this speed as
desired). After desiccation, the flax is placed in a stove or drying room, before
passing to the stripping knife.
My improved process of chemical retting or steeping flax therefore requires,
per ton (metrical) of flax, 80 kilogrammes of soap and 30 litres of hydrochloric
acid. By this improved process is obtained flax of a superior quality to that
obtained by former processes in which, the fermentation varying according to the
temperature, the stalks which are in the centre of the bundles are desomposed first
and will be subjected to a more energetic decomposition than the stalks upon the
outsides of the bundles in such a manner that retting or steeping is irregular.
By my improved process, on the contrary, a regular and homogeneous retting
or steeping is obtained.
The cost of drying, in my improved process is appreciably less, than in the
processes hitherto employed, the manufacturer is no longer at the mercy of change
in the weather; there is no waste; moreover, the whole of the work can be carried
on throughout the year without interruption.
My improved process, moreover, permits the recovery of lignin and other bye-
products contained in the flax stalk.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed I declare that what
I claim is:-
-
1. The hereindescribed process of retting or steeping flax by the combined
action of soap and acids (preferably hydrochloric acid), for the purposes specified.
2. The treatment of flax in the apparatus herein before described with reference
to the drawing, substantially as, and for the purposes specified.
3. The improved apparatus for use in retting or steeping flax constructed sub-
stantially as described with reference to the drawing.
Dated this 19th day my 19
JU.
D. YOUNG & CO.,
11 & 12, Southampton Buildings, London, W.C.,
Agents for the Applicant.