Process and Apparatus for Extracting the Colouring Matter from Dyewoods.
Year: 1895

page_text: Date of Application, 4th Apr., 1895
Complete Specification Left, 19th Dec., 1895-Accepted, 1st Feb., 1896
PROVISIONAL SPECIFICATION.
Process and Apparatus for Extracting the Colouring Matter from
Dyewoods.
I, FRANÇOIS Edouard Mafat, of 12 Rue des Lious St. Paul, Paris, France,
Manufacturer, do hereby declare the nature of this invention to be as follows:-
Hitherto, according to the processes known as those of Kohlrausch and others,
the colouring matters of dyewoods have been extracted by treating the woods in a
series of vessels operating in rotation, the water acting first on the wood from
which most of the colour had been extracted and last on the wood fresh supplied.
These processes, however, failed to effect complete extraction of the colouring
matters whether acting under pressure or not or at high or low temperatures.
The present invention relates to means of effecting radical extraction of the
colouring matters, using for that purpose vacuum produced by an air pump or
steam ejector and methodical diffusion. The presence of air in the pores of the
dyewoods prevents radical extraction of the colouring matter, but by, in the first
place, subjecting the dyewoods to vacuum in the vessels, the air is removed from
the pores of the wood, leaving the colouring matter completely accessible to the
dissolving action of the water.
For this purpose, I arrange either in line or circularly a set of close vessels
generally five in number with sets of pipes for air, water, steam and juices, and a
vacuum pump or ejector.
Each vessel is in the first place charged with a certain quantity of the dyewood.
The first vessel being cut off from the others is exhausted of air and is then
supplied with hot water which is kept hot and active for extracting by steam
circulating through a coil submerged in the liquid in the vessel.
While extraction is going on in the first vessel, the second is exhausted, and then
the liquor from the first vessel is admitted to it and, fresh water being admitted to
the first, both are boiled while a vacuum is made in the third, which is then
supplied with juice from the second, the second again receiving juice from the first
which again receives fresh water. The contents of the first, second and third are
boiled while a vacuum is made in the fourth. The fourth then receives liquor
from the third, the third from the second, the second from the first, which is again
supplied with fresh water. Boiling again goes on while a vacuum is made in the
fifth vessel and again a transfer of liquor from vessel to vessel is made, and boiling
goes on while the first has the spent wood discharged from it, fresh wood supplied
and a vacuum made in it. The first vessel now receives the strong liquor from the
fifth and this after boiling is discharged.
The succession of operations now goes on, the second vessel now taking the place
of the first, and the first taking the place of the fifth.
Each of the vessels employed has the special form of a conical frustrum wider
at the bottom than at the top, & has near the bottom the steam coil under a grating
on which the fragments of dyewood are laid. The pipes for supply of steam and
water, for exhausting the air and for communicating from one vessel to another, are
furnished with suitable cocks or valves and the vessels are provided with vacuum
gauges.
Dad thi
.
$1 1005
ABEL & IMRAY,
Agents for the Applicant.

page_text: Process and Apparatus for Extracting the Colouring Matter from
Dyewoods.
I, FRANÇOIS EDOUARD MAFAT, of 12 Rue des Lions St. Paul, Paris, France,
Manufacturer, 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 :-
Hitherto, according to the processes known as those of Kohlrausch and others,
the colouring matters of dyewoods have been extracted by treating the woods in a
series of vessels operating in rotation, the water acting first on the wood from
which most of the colour had been extracted and last on the wood fresh supplied.
These processes, however, failed to effect complete extraction of the colouring
matters whether acting under pressure or not or at high or low temperatures.
The present invention relates to means of effecting radical extraction of the
colouring matters, using for that purpose vacuum produced by an air pump or
steam ejector and methodical diffusion.
The presence of air in the pores of the dyewoods prevents radical extraction of
the colouring matter, but by, in the first place, subjecting the dyewoods to vacuum
in the vessels; the air is removed from the pores of the wood, leaving the colouring
matter completely accessible to the dissolving action of the water.
For this purpose, as shewn in the accompanying drawing, I arrange, either in
line as shewn, or it might be circularly, a set of close vessels A, generally five in
number, with sets of pipes for air, water, steam and juices, and a vacuum pump or
ejector.
Each vessel A is, in the first place, charged with a certain quantity of the
dyewood. The first vessel A¹, being cut off from the others, is exhausted of air
and is then supplied with hot water which is kept hot and active for extracting by
steam circulating through a coil submerged in the liquid in the vessel.
While extraction is going on in the first vessel A, the second A' is exhausted,
and then the liquor from the first vessel A¹ is admitted to it and, fresh water being
admitted to the first, both are boiled while a vacuum is made in the third A,
which is then supplied with juice from the second A³, the second again receiving
juice from the first A', which again receives fresh water. The contents of the
.first, second and third are boiled while a vacuum is made in the fourth A' which
then receives liquor from the third As, the third from the second A³ the second
from the first A³, which is again supplied with fresh water.
a
Boiling again goes on while a vacuum is made in the fifth vessel A', and again
transfer of liquor from vessel to vessel is made, and boiling goes on while the
first A¹ has the spent wood discharged from it, fresh wood supplied and a vacuum
made in it.
The first vessel A¹ now receives the strong liquor from the fifth A' and this
after boiling is discharged.
The succession of operations now goes on, the second vessel A³ now taking the
place of the first, and the first taking the place of the fifth.
Each of the vessels employed has the special form of a conical frustum wider
at the bottom than at the top, and has near the bottom the steam coil C under a
grating G on which the fragments of dyewood are laid.
The pipes for supply of steam and water, for exhausting the air and for
communicating from one vessel to another, are furnished with suitable cocks or
valves, and the vessels are provided with vacuum gauges, and with doors for
introducing the fresh dyewood and withdrawing that from which the colouring
matter has been extracted.

page_text: Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
1. The herein described process for extracting colouring matter from dyewood
by subjecting the wood to vacuum and successive boilings with juices of less and
less strength, and finally with water.
2. For operating as above set forth a series of vessels constructed and connected
by suitable pipes with each other and with vacuum vessels steam and water
supplies, substantially as described.
Dated this 10th day of December 1895
ABEL & IMRAY,
Agents for the Applicant.