A New Process and Apparatus for Treating Soluble and Partially Soluble Gums so as to Render them Fit for Industrial Purposes.
Year: 1888

page_text: Date of Application, 1st Sept., 1888
Specification Accepted, 5th Oct., 1888
A New Process and Apparatus for Treating Soluble and Partially
Soluble Gums so as to Render them Fit for Industrial Purposes.
1, ALFRED NAYLOR PEARSON, of Cunningham Street, Northcote, in the Colony of
Victoria, Agricultural Chemist, 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 :-
This invention has been designed for the purpose of providing a process and
apparatus whereby soluble and partially soluble gums may be converted into an
article suitable for industrial purposes.
Hitherto wattle gum has been declared useless for industrial purposes, principally by
reason of its supposed insolubility. Now by my invention I am enabled to utilize
this article so as to make it an equivalent for what is generally known as "gum
arabic."
This process consists shortly first, in dissolving the soluble portion of the gun.
Secondly in filtering the solution so produced. Thirdly in concentrating this solution
by evaporation and Fourthly, either to pour it into trays or to allow it to percolate
through holes in a plate or vessel and then to dry it. When a more refined article is
required decolorize the solution before concentration by means of coagulable or
precipitable material such as albumen.
The greatest difficulty that has been met with in the endeavour to use wattle gum
for industrial purposes has been the inability of the persons so making such endeavour
to dissolve the soluble portion of it in such a way as to be of any practical use.
Now I have overcome this difficulty by dissolving the gum whilst it is held in
suspension in water instead of plucing the whole bulk of the gum on the bottom
of the vessel.
In practice I make a dissolving vat of any required size and of any suitable
material such as iron and in this vessel I suspend a tray or a number of trays one
above the other each made of some foraminous material such as wire gauze or
perforated metal.

page_text: In my drawings Figure 1 shews a plan and Figure 2 a section of such a vat in
which A is the rat and B the trays supported by central shaft B¹ which rests on
the bottom of the vat.
I find that pieces of wattle gum of the size of a duck's egg dissolve within twelve
hours thus if such gum be placed in suspension in cold water in the evening it will
be all dissolved by the time the workmen arrive in the morning.
After the gum has been thus dissolved I filter it through a filtering press of special
construction as shewn in Figures 3 and 4 of my drawings in which C is a solution
receptacle having a hole in its bottom covered with wire gauze and leading into a
pipe D which extends downwards into a closed vessel E in which is a floor or tray
of foraminous material covered with a layer of sand.
After having thus filtered the solution I concentrate it by evaporation to any extent
for office purposes
to which it may be desired say, either for use as a solution of gum
or if the solution is made sufficiently viscid I allow or compel it to flow slowly through
holes in a plate which may either be horizontal or vertical and may form the bottom or
sides of a vessel. This should be done in a warm atmosphere say one hundred and
twenty degrees to one hundred and forty degrees Fahrenheit so as to congeal in drops
or in such forms as it may naturally assume or may pour it into shallow trays and
allow it to set drying it at a temperature not high enough to produce discoloration say
any temperature below two hundred and twelve degrees Fahrenheit.
In some cases where a more refined product is required such as for confectionery or
for medicinal purposes I decolorize the solution either before or after filtration but
preferably after filtration by adding to it a sufficient quantity of coagulable or precipi-
table material (such as albumen) to absorb the colouring matter therein and by
then separating the coagulated or precipitated material from the solution by filtration.
In practice I find that the albumen of one egg is sufficient for about six pounds of the
solution.
Any bitter taste which the gum might originally possess would be removed by the
albumen unless it were considerable in which case it might be removed by gelatine or
hides as is well known.
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is :-
First. The process substantially as herein described and explained for treating
soluble and partially soluble gums so as to render them fit for industrial purposes con-
sisting essentially in dissolving them while held in suspension in water thon filtering
such solution, then concentrating it by evaporation and when required in a solid state
pouring it into trays or allowing it to percolate through holes and then allowing it to
dry and when required in a more refined condition decolorizing it preferably after
filtration by coagulable or precipitable materials such as albumen.
Second. The improved apparatus used for treating the gums in the aforesaid process
and consisting, firsi, of a vessel having one or a series of foraminous trays or supports
for the gum arranged one above the other and, second, of a filter having a receiving
chamber leading to a long pipe discharging into a closed chamber containing a forami
nous tray covered with a layer of sand substantially as herein described and explained
Dated this Twenty-sixth day of July
One thousand eight hundred and eighty-eight.