IMPROVEMENTS IN THE TREATMENT OF STRAW, STRAW REFUSE OR OTHER FIBROUS MATERIALS FOR THE MANUFACTURE OF PULP AND MANURE
Year: 1883

page_text: ·LETTERS' PATENT to Thomas Henry Cobley of Dunstable in the County of
Bedford for an Invention of "IMPROVEMENTS IN THE TREATMENT OF STRAW,
STRAW REFUSE OR OTHER FIBROUS MATERIALS FOR THE MANUFACTURE OF
PULP AND MANURE
"
PROVISIONAL SPECIFICATION left by the said Thomas Henry Cobley at
the Office of the Commissioners of Patents on the 23rd July 1883.
THOMAS HENRY COBLEY of Dunstable in the County of Bedford
MENTS IN THE TREATMENT OF STRAW, STRAW REFUSE OR
MATERIALS FOR THE MANUFACTURE OF PULP AND MANURE
"
"IMPROVE-
OTHER
FIBROUS
My invention relates to the treatment of straw, straw refuse, such as straw
manure or stable litter, waste straw paper or cuttings of straw paper or board, and
other fibrous materials, for the manufacture of pulp for paper or board, and to the
treatment of the waste and by products for manufacture of manure.
For treating straw or comparatively clean fibrous material, I cut it into lengths
of about one inch and steep these for several days in water charged with chlorides,
such as calcium, magnesium or other chlorides, or mixtures of these, using these in
the proportion of about 3 per cent of the weight of material treated. The
maceration may be promoted by a jet of steam. After maceration, the material is
boiled in a steam jacketted boiler provided internally with rollers or other known
pulping apparatus, with liquor, which, for brown paper pulp, contains lime or a
mixture of this and a salt of lime such as calcium chloride, and for white paper.
pulp, contains caustic soda or black ash or causticised potassical waste from wool
washing, or a mixture of caustic soda and calcium chloride. The material, after
being boiled with lime for brown pulp, is washed in the usual way and slightly
acidulated, and may to a certain extent be bleached by treatment with soda ash.
The material after being boiled with alkali for white pulp, is washed and treated
with a small quantity of calcium chloride having excess of hydrochloric acid, or
with magnesium chloride under the influence of heat. It is preferably, passed

page_text: through a knotter to remove crude particles, and it is then bleached with a solution
of chloride of lime or of hypochlorite of Potassa and Magnesia obtained by
decomposition of chloride of lime and. Kieserite. After bleaching, the pulp is
washed, squeezed and dried by hot air, and it may be teased or brushed out into
fibre.
In treating cuttings or waste of straw paper or board, maceration is not
required. The material is merely chopped into shreds and boiled as described for
the straw, using for production of brown pulp, a liquor containing nitre cake or
acid sulphate of soda and nitrate of soda, and for white pulp a liquor containing
soda ash.
In treating straw manure or litter, the maceration after shredding is continued
longer than for the straw, and the steeping liquid is kept in circulation by pumping
or agitation, so as thoroughly to wash out the non-fibrous matter which is from
time to time allowed to settle and removed to be converted into manure. The
fibrous matter, after boiling under pulping action, is passed through squeezers to
remove completely any residuary manure matter, and is then treated for brown or
white pulp as above described for straw.
The black liquor resulting from the boiling after draining and squeezing the
pulp is mixed with quick or partly slaked lime and evaporated to the condition of
a stiff paste, from which is washed caustic liquor available for subsequent boiling.
The black liquor resulting from the partial bleaching of the lime boiled material
may be causticised by boiling with lime, without previous evaporation.
The sludge resulting from the maceration of the straw manure or litter is treated
for precipitation with a salt of alumina or alumina and iron. The precipitate is
then partially dried in a filter press or centrifugal machine, and farther dried for
transport as manure by addition of phosphatic or nitrogenous waste, preferably
crag phosphate or phosphatic slag calcined with Kainite and pulverised with
admixture of soot or nitrate of soda.
As a size or filling for brown paper or board, I employ waste of leather and glue
which is dissolved in the black alkaline boiling liquor, and then precipitated by
lime and afterwards sulphate of alumina.
In order to avoid too great darkness of colour, when the leather contains tannin,
the sulphate of alumina should be cleared of iron by precipitation.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Thomas Henry Cobley in the Patent Office on the 22nd January
1884.
"
IMPROVE-
OTHER FIBROUS
THOMAS HENRY COBLEY of Dunstable in the County of Bedford
MENTS IN THE TREATMENT OF STRAW, STRAW REFUSE OR
MATERIALS FOR THE MANUFACTURE OF PULP AND MANURE
"
My invention relates to the treatment of straw, straw refuse such as straw
manure or Stable litter, waste straw paper or cuttings of straw paper or board and
other fibrous materials for the manufacture of pulp for paper or board, and to the
treatment of the waste or by products for the manufacture of manure.
For treating straw or comparatively clean fibrous material, I cut it into lengths
of about one inch or more and steep or macerate these in water charged with
chlorides, such as the chlorides of calcium, magnesium and other chlorides or
mixtures of these, using these in the proportion of about 3 per cent of the dry
weight of the material treated.
If treated cold the steeping or maceration should be continued several days, if
warm then a shorter time will be sufficient. After steeping or maceration, the
material is boiled in a boiler preferably steam jacketted and provided internally
with rollers, stirrers or agitators or other known pulping apparatus, in contact
with a liquor which, for Brown paper pulp, should contain lime or a mixture of
lime and lime salt such as calcium chloride, and for White paper pulp, a liquor
containing caustic soda or a solution of so called Black Ash or Potassical waste
liquor from washing or scouring of Wool after causticising, mixed with chloride of
calcium. The steeps or macerating pits may be employed as boilers by increasing
the amount of steam introduced by means of coils and adding the soda or potassical
liquors to the steeping liquor.
The material for brown paper pulp after boiling is washed in the ordinary or
any convenient manner, and then acidulated with an acid such as sulphuric or
hydrochloric acid, in the proportion of at least half a per cent of the weight
of material. It may then be partially bleached or the coloring matter to a
great extent withdrawn by treatment with a solution of soda ash (meaning
carbonate of soda) the organic coloring matter being largely soluble in carbonate
of soda.
The material, boiled with alkali for white pulp, is washed and treated with
Acichloride of calcium or magnesium that is chloride of calcium or magnesium
containing an excess of hydrochloric acid, about 3 parts of the salt and 1/2 to 1 part
of the acid to 100 parts of the dry weight of the material. Previous to bleaching,
it is preferably passed through a coarse knotter or strainer so as to remove the
sheaves or crude particles and impurities, and afterwards bleached with a solution
of chloride of lime or hypochlorite of potash and magnesia obtained by the double
decomposition of chloride of lime and kainite.
After bleaching, the pulp is washed, squeezed through india rubber rolls and
dried by hot air.
In treating cuttings or waste of Straw paper or board, maceration is not required.
The material is merely chopped into shreds and boiled as described for the straw,
using for the production of brown pulp a liquor containing "Nitre Cake" or acid
sulphate of soda with a small quantity of nitrate of soda, for the production of
white pulp, a liquor containing soda ash or carbonate of soda.
In treating straw manure or stable litter, the maceration or steeping after the
cutting or shredding is continued longer than for the straw, and the steeping
liquids are kept in circulation by pumping or agitation, so as thoroughly to wash
out the non fibrous matter which is from time to time allowed to settle and
afterwards removed to be converted into manure.
The liquor employed in maceration should also be stronger than for the straw

page_text: '
and brought up to 5 per cent of the chlorides, as described for straw with the
addition of a little chloride of iron.
The fibrous material or matter is passed through squeezers to remove completely
any residuary manuring matter, and, after boiling under pulping action as
described for straw with the addition of the same chemical agents for brown or
white pulp as in the case with straw.
The black liquor resulting from the boiling after draining is mixed with fresh
quick lime or such partially slaked and evaporated down to the condition of a
stiff paste, from which is washed caustic liquor available for subsequent boiling.
The black liquor resulting from the treatment of the lime boiled material may
be causticised for the same purpose by boiling with lime without evaporation.
The liquor or sludge resulting from the maceration of the straw manure or litter
is treated for precipitation with a salt of alumina or alumina and iron. The
precipitate is then deprived of its moisture by passing through a filter press or
hydro-extractor centrifugal machine, and further dried for transport as manure.
Additions may be made of a nitrogenous, phosphatic or potassical_character;
which at the same time act also as driers. For the nitrogenous matter, I prefer to
add nitrate of soda and soot; for phosphatic matter combined with the potassical
admixture of phosphatic Slag, Crag phosphate (Coprolite) and Kainite (mineral
potash) fused together and ground up with the precipitate."
As a size or filling for brown paper or Board, I employ leather waste or glue
waste, which is rendered soluble by boiling with alkaline liquor. Waste liquor from
previous boiling of fibre will answer equally well, and in its application as a size it
may be precipitated on to the fibrous mass or pulp as in the ordinary process of
sizing, by the addition of alum or sulphate of alumina, but it is preferable and
more economical to use a certain portion of milk of lime in the sizing operation,
which proportion may be one half the amount of lime to the salt of alumina
ordinarily employed to produce precipitation, the lime to be added after the
alumina.
As regards color, where the paper is required of a brown color and excessive
darkness is to be avoided, the alum or sulphate of alumina employed must be
rendered free of iron by previous precipitation, and leather waste previously
deprived of its tannin. But where dark color up to black is desired, then the
leather waste employed for sizeing and filling is that containing the largest amount
of tannin, and the salt of alumina must contain iron, if not sufficient which may be
in the case where a black is required, then the necessary quantity of salt of iron is
added until the desired tint or shade is produced. In the case of black, no lime
should be used. This method of sizing will produce a paper of great tenacity,
of a fine surface and very impervious to water.
Having thus described the nature of my invention and in what manner the same
is to be performed, I claim
First. The process, substantially as herein described, in treating straw or its
equivalent for the manufacture of pulp suitable for brown paper or board.
Second. The process, substantially as herein described, in treating straw or its
equivalent for the manufacture of pulp suitable for white paper or board.
-Third. The process, substantially as herein described, in treating the refuse from
the pulp manufacture referred to in the preceding claims, for the production of
manure.
In Witness whereof I the said Thomas Henry Cobley have hereunto set my hand
and seal this Twenty first day of January in the year of our Lord One thousand
eight hundred and eighty-four.
THOMAS: HENRY: COBLEY
(L.S.)