An Improved Method of and Means for Protecting Apparatus Used in the Manufacture of Sulphite Cellulose.
Year: 1888

page_text: Date of Application, 17th Sept., 1888
Complete Specification Left, 14th June, 1889-Accepted, 20th July, 1889
PROVISIONAL SPECIFICATION.
An Improved Method of and Means for Protecting Apparatus Used
in the Manufacture of Sulphite Cellulose.
We FERDINAND SALOMON of Mohrenstrasse 59 Berlin, and HERMANN BRÜNGGER
of Cunnersdorf in the District of Liegnitz Factory Manager, do hereby declare the
nature of this invention to be as follows:
This invention relates to a method of preventing the destructive action of sulphite
lyes upon the boiling apparatus used in the manufacture of sulphite cellulose.
Boiling apparatus heretofore employed in the manufacture of sulphite cellulose has
been provided with an inner lining of lead or brickwork, with the object of preventing
the destruction of the iron shell of the boiler by the sulphite lye.
But this method of protecting the boiling apparatus, has the disadvantage, that
the lining of the shell is liable to leak, thereby necessitating constant repairs or
frequent renewals of the lining, and thus causing interruption in the working of the
apparatus. In consequence of this liability of the protective lining to leak, the
boiling apparatus is also liable to be destroyed and must be often repaired or
renewed.
The present invention has for object to obviate these disadvantages, and consists
essentially in causing a protective crust from the sulphite lyes to form or settle upon
the exposed surfaces of the boiling apparatus, by the application of heat. The walls
of the boiling apparatus. having been heated to a suitable temperature (say 130°),
they are brought into contact with the sulphite solution; the latter boils where it is
in contact with the hot walls, and is thereby partly decomposed, the result being the
deposition of a firm, dense, permanent crust of about 1 to 2 millimetres in thickness.
This crust is composed mainly of gypsum (formed by the oxidation of calcium
sulphite) and calcium monosulphite, and is so dense that it protects the underlying
surface from the destructive action of the lye.
.
In boilers or boiling apparatus capable of being rotated, hose parts which are to
be protected by a coating deposited from the boiling lye, are constructed with double
walls, in order that the heating of the parts to be treated or protected may be
effected by means of a heating medium introduced into the intermediate space.
The spaces between the double walls of the manholes, and unions (if any) are
connected by means of pipes with the spaces between the double walls of the boiler
shell.
A pipe conveys steam or other heating medium into these intermediate spaces.
The boiler may be rotated by means of rollers, so as to enable all parts of it to be
brought into contact with the steam, and thus become heated.
The filling of the boiler with sulphite solution and the rotation are effected in such
a manner that the entire inner surface of the boiler shall come in contact with the
sulphite lye.
Steam is conducted by the steam pipe into the spaces between the double walls,
until the inner surfaces have reached a suitable temperature (say 130°).
The lye is then admitted into the boiler, and on coming in contact with the heated
inner surfaces of the boiler, a portion of the lye begins to boil, and is thereby partly
decomposed with deposition of insoluble calcium sulphite and gypsum.
The latter substance is produced by the oxidation of the calcium sulphite by the
oxygen of the air. As a result of this operation the parts which had been previously
heated and then covered by the lye, become coated with a uniform, firm, protective
coating. Any parts that may become worn are automatically renewed during subsequent
boiling processes in a manner similar to that just described.

page_text: By this means boilers can be employed in the manufacture of sulphite cellulose,
whose inner walls are not provided with protective linings of the kinds heretofore
employed.
Dated this 17th doy of So tomber 1000
FERDINAND SALOMON,
Per L. W.
HERMANN BRÜNGGER.
Per L. W.
COMPLETE SPECIFICATION.
An Improved Method of and Means for Protecting Apparatus Used
in the Manufacture of Sulphite Cellulose.
We, FERDINAND SALOMON, of Mohrenstrasse, 59 Berlin and HERMANN BRÜNGGER,
of Cunnersdorf, in the district of Liegnitz, Factory Manager, 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 relates to a method of preventing the destructive action of sulphite lyes
upon the boiling apparatus used in the manufacture of sulphite cellulose.
Boiling apparatus heretofore employed in the manufacture of sulphite cellulose has
been provided with a inner lining of lead or brickwork, with the object of preventing
the destruction of the iron shell of the boiler by the sulphite lye.
But this method of protecting the boiling apparatus has the disadvantage, that
the lining of the shell is liable to leak, and frequently requires repair and renewal and
thus causing interruption in the working of the apparatus. In consequence of this
liability of the protective lining to leak the boiling apparatus is also liable to be
destroyed and must be often repaired or renewed.
The present invention has for object to obviate these disadvantages and consists
essentially in causing a protective crust from the sulphite lyes to form or settle upon
the exposed surfaces of the boiling apparatus by the application of heat.
The walls of the boiling apparatus having been heated to a suitable tempera-
ture 100° C. or more the sulphite solution is brought into contact with them so that
the solution boils where it is in contact with the hot walls and is thereby partly
decomposed the result being the deposition of a firm, dense, permanent crust of about
1 to 2 millimetres in thickness. This crust is composed mainly of gypsum (formed
by the oxidation of calcium sulphite) and calcium mono-sulphite, and is so dense that it
protects the underlying surface from the destructive action of the lye.
In boilers or boiling apparatus capable of being rotated those parts which are to
be protected by a coating deposited from the boiling lye, may be constructed with
double walls, in order that the heating of the parts to be treated or protected may
be effected by means of a heating medium introduced into the intermediate space.
In the iron boiler A shewn in longitudinal section in Fig. 1 of the accompanying
drawings the entire shell B and the manholes and other unions C are constructed with
double walls as shewn.
The spaces between the double walls of the man holes and unions are connected
by means of pipes D with the spaces between the double walls of the boiler shell.
A pipe F serves to convey steami or other heating medium into these intermediate
spaces. The boiler may be rotated by means of rollers E, so as to enable all parts.
of it to be brought into contact with the steam and thus become heated.
The filling of the boiler with sulphite solution and the rotation are effected in such
a manner that the entire inner surface of the boiler shall come in contact with the
sulphite lye. Steam is conducted by the steam pipe F into the spaces between
the double walls until the inner surfaces have reached a suitable temperature (100° C.
or more).
The, fibrous material and the lye are then admitted into the boiler, and on coming
in contact with its heated inner surfaces a portion of the lye begins to boil, and is
"

page_text: thereby partly decomposed with the deposition of insoluble calcium sulphite and
gypsum.
The latter substance is produced by the oxidation of the calcium sulphite; as a
result of this operation the parts which had been previously heated and then covered
by the lye, become coated with a uniform, firm, protective coating. Any parts that
may become worn are automatically renewed during subsequent boiling processes in a
manner similar to that just described.
By this means boilers can be employed in the manufacture of sulphite cellulose,
whose inner walls are not provided with linings, of the kinds heretofore employed.
For heating rotary boilers with single walls, as shewn in vertical section in Fig. 2,
there may be provided externally a covering of masonry formed with openings G and H
corresponding to the manholes and union C in the boiler shell. The heating of the
boiler shell is effected by means of hot gases such as products of combustion, or hot
air, which are introduced into the space between the boiler and the masonry, so that the
boiler is thereby heated to the requisite temperature. The heating of the shell is
continued during the duration of the boiling this heating serving at the same time
to effect this boiling.
Non rotating or fixed boilers with signal walls may also be provided with a covering
of masonry as shewn in vertical section in Fig. 3. The boiler in this case is provided
with a pipe leading to a closed vessel J that is situated within the covering of
masonry. When such long rotating or fixed boilers with single walls have been
sufficiently heated, they should be completely filled with the solution in order to
produce the deposit of scale on the entire inner surface of the boiler. The vessel J
then serves to receive the excess of liquid which overflows owing to expansion. The
vessel J, and the pipe connecting it with the boiler are (as we prefer) provided with
valves VV which are so loaded that the pressure in the vessel J shall be somewhat
lower than in the boiler proper. The heating of the boiler shell and the subsequent
heating of the contents of the boiler is effected as in the arrangement of rotating
boilers with a single wall.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed we declare that what we
claim is
1. For protecting apparatus used in the manufacture of sulphite cellulose the
method of depositing a protective coating or film on the internal surface of the
boiling vessel by heating from the outside the bare internally exposed iron or steel
wall of the said vessel to a temperature of or exceeding 100° C. and then admitting
sulphite solution into contact with the so heated internal surface of the said vessel and
exposing it to the action of heat from without.
2. In the manufacture of sulphite cellulose the use or employment for the purpose
of boiling the cellulose matter of an iron or steel vessel having a protective lining,
coating or film deposited from cellulose sulphite solution directly upon the internal
surface or wall of the vessel substantially in the manner set forth.
Dated this 14th day of June 1889
W. LLOYD WISE,
Per F. J. Brougham,
46, Lincoln's Inn Fields, London, W.C., Agent for the Applicant.