IMPROVE- MENTS IN BOILERS OR DIGESTERS TO BE EMPLOYED IN THE TREATMENT OF PAPER MAKING MATERIALS OR FOR ANALOGOUS OPERATIONS
Year: 1884

page_text: PROVISIONAL SPECIFICATION:
I, THOMAS ROUTLEDGE, of Ford Works, Sunderland, in the County of Durham,
Paper Manufacturer, do hereby declare the nature of said Invention for "IMPROVE-
MENTS IN BOILERS OR DIGESTERS TO BE EMPLOYED IN THE TREATMENT OF PAPER
MAKING MATERIALS OR FOR ANALOGOUS OPERATIONS "
to be as follows:-
My Invention has for its object to obviate many of the objections at present
existing in Boilers or Digesters as hitherto employed in the treatment of Wood and
other Fibrous substances for the preparation of Paper-making materials or for
textile purposes or in the treatment of grain or amylaceous substances, in making
Glucose or in analogous operations more especially when acid solutions under high
pressure or an elevated temperature are employed for such purposes.
In such operations it is customary to line the interior of the Boilers or Digesters
and their connections with Lead or to construct them of a Bronze or other compound
metal on which the said acid solutions shall have little or no prejudicial effect.
Such Boilers or Digesters however are expensive in first cost, and in maintenance
are very liable to get out of order and constantly require repairs this being
especially the case when such vessels are constructed of iron or steel lined with
lead, due to the difference in expansion and contraction under heat between Iron
and Lead.
According to my Invention I construct such Boilers or Digesters of Lead alone
of suitable thickness or substance to withstand the degree of pressure to be
employed and according to their capacity or dimensions. Such vessels may be
constructed in any convenient manner from Lead in Sheets or Plates or by casting
in sections or otherwise, the joints both in the vessels themselves and their
connections being united in the customary manner by burning or otherwise.
I lay no claim to any special form of boiler or digester, which may be either
stationary or rotating; nor to any special manner of heating the contents or for
maintaining the requisite temperature in such Vessels, nor to the acid or other
solutions employed, these details and particulars having been fully described and
specified in the Patents (now lapsed) No 2924 of 1866 and No 385 of 1867 taken.
for Telghman's Inventions:
Dated this 15th day of September 1884.

page_text: I THOMAS ROUTLEDGE of Ford Works Sunderland in the County of Durham
Paper manufacturer do hereby declare the nature of my invention for "IMPROVE-
MENTS IN BOILERS OR DIGESTERS TO BE EMPLOYED IN THE TREATMENT OF PAPER
MAKING MATERIALS OR FOR ANALOGOUS OPERATIONS" and in what manner the
anime is to be performed, to be particularly described and ascertained in and by
the following statement:-
My Invention has for its object to obviate many of the objections at présent
arising in the use of the existing boilers or digesters employed for the treatment
of wood and other fibrous substances for the preparation of paper making materials
or for textile purposes in cases where acid solutions under high pressure or an
elevated temperature are employed or in the treatment of grain or amylaceous
substances in making Glucose or in analogous operations where acid solutions are
employed.
In such operations it has hitherto been customary to line the interior of the
boilers or digesters and their connections (when treating wood or other fibres by
acid solutions) with lead and also (when using acid solutions for trenting grain or
other amylaceous substances) to construct the said boilers or digesters of a bronze
or equivalent alloy so that the acid of the solutions shall have little or no
prejudicial effect on the interiors of the said boilers or digesters.
Boilers or digesters so made are however expensive in first cost and in
maintenance, are very liable to get out of order and constantly require frequent
repairs this being especially the case when such vessels are constructed of iron or
steel lined with lead and is mainly due to the difference in expansion and
contraction under beat between iron or steel and lead.
According to my Invention I construct such boilers or digesters of lead alone of
suitable thickness or substance to stand the highest degree of pressure to bo
employed in the process for which the said boilers or digesters are used and in
accordance with the capacity and dimensions of the mid boilers or digesters. The
Enid boilers or digesters may be constructed or formed from the lead in any
convenient manner either from lead in sheets or plates or by casting in sections or
otherwise the joints both in the vessels themselves and their connections being
united in the customary manner by burning or otherwise.
The addition of antimony to the lead will harden the lead and render it liable
to expansion and contraction to a lesser extent. In place of antimony any other
metal (such for example as manganese) which will make an alloy with the
load and harden it and render it liable to expansion and contraction to a lesser
degree may be used provided that it is not of a nature when so alloyed to be
injuriously acted upon by acid.
I lay no claim to any special form of boiler or digester which may be either
stationary or rotating nor to any special manner of heating the contents or of

page_text: maintaining the requisite temperature in such vessels nor to the acid or other
solutions employed these details and particulars being known and having been fully
described and specified in the specifications of patents (now lapsed) N° 2924 of 1866
and N° 385 of 1867 taken for Tighlman's Inventions.
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
Constructing boilers or digesters (for treating paper making materials or for
analogous purposes or operations) of lead either alone or with the addition of
antimony or the like as hereinbefore described.