An Improvement in Boilers used in the Manufacture of Paper Pulp.
Year: 1890

page_text: Date of Application, 8th Feb., 1890
Complete Specification Left, 8th Nov.. 1890-Accepted. 13th Dec... 1890
PROVISIONAL SPECIFICATION.
An Improvement in Boilers used in the Manufacture of Paper Pulp.
A communication, to me from abroad by CARL KELLNER, of Vienna, Austria, Chemist.
I CHARLES ADRIAN DAVIES of 4 St. Ann's Square Manchester in the County of
Lancaster Patent Agent do hereby declare the nature of this invention to be as
follows:
Hitherto the boilers used in the manufacture of paper pulp have been generally
lined with sheet lead to resist the action of the acid solutions employed in such
manufacture.
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This lead has had to be applied in segments or sections and great difficulty has been
experienced in making good the joints between the said segments or sections so as
to render them proof against the corrosive and penetrating liquors.
By this invention however a jointless and seamless lining formed in the boiler in
place of the lead segments or sections, and the invention consists in applying to the
interior thereof (after the boiler has been put together in the usual manner) a layer
or coating of an acid resisting cement of suitable composition and thickness, which
will not be liable to creep or leave the surface of the boiler under the action of
the heat.
This coating will be cheaper and in many other ways more advantageous than the
lead linings now employed.
Portland cement mixed with fine sand has been found suitable for the above
purpose.
Dated this 7th day of February 1890.
COMPLETE SPECIFICATION.
An Improvement in Boilers used in the Manufacture of Paper Pulp.
A communication to me from abroad by CARL KELLNER, of Vienna, Austria, Chemist.
I CHARLES ADRIAN DAVIES of 4 St. Ann's Square Manchester in the County of
Lancaster, Patent Agent 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 the bodies or digestors used in the manufacture of paper pulp have been
generally lined with sheet lead to resist the action of the acid or corrosive solutions
employed in such manufacture.
This sheet lead has had to be applied in segments or sections and great difficulty
has been experienced in making good the joints between the said segments or sections
so as to render them proof against the corrosive and penetrating action of such
liquors or solutions and also in preventing the "creeping" action and consequent
loosening and cracking of the lead due to its expansion and contraction being different
from that of the steel or iron of which the boiler or vessel itself is constructed.
By the use of this invention, however, a perfectly jointless and seamless lining is
formed inside the boiler, in place of the lead segments or sections as hitherto
employed.
The invention consists in applying to the interior of the boiler after the same has
been put together in the usual manner a layer or coating (or two or more layers or
coatings) of an acid resisting cement in place of the lead lining hitherto employed.
Such coating or coatings of acid resisting cement will be laid on with a trowel or
otherwise to a suitable thickness and then dried or burnt on if necessary, and the
D

page_text: cement or similar composition employed for this purpose must be of such a nature as
will resist the action of the corrosive acids and will not be liable to "creep" or crack
or leave the surface of the boiler under the action of the heat.
This coating will be not only much cheaper in its first application than the lead
lining but in many other ways it will be found to be more advantageous and
economical and in case of any crack or breakage occurring it can always be fresh
pointed with cement by any unskilled workman competent to use a trowel.
Portland cement mixed with fine sand in about equal proportions has been found
suitable for the above purpose but various other cements or acid proof compositions
might be employed with advantage.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed I declare that what I
claim as the invention communicated to me is:
In the manufacture of paper pulp, the use of a jointless and seamless lining, to the
boilers therein employed, of Portland or other acid resisting cement or composition
in place of the lead lining hitherto generally employed.
Dated this 7th day of November 1890.
CHARLES A. DAVIES.