New-York tribune., 1909-03-07
HOW sULPHITE PULP IS MADE.

The r7alfna, # s-phite pulp is elaborate
process The -liquvT.' acid for cooking the ciIs
is made from waste marble lime, and sulphur
in "a series az acid towers each thiTty-one inches
Sc diameter and constructed Of wood, housed N
building 100 fest high, the mill visited Briefly
1ne action ~ sulphur and water on the line makes
q sGipnurous acid The sulphur is burned IN re-
torts at the base Of and at a short distance FROM
these towers each retort or stove. having its own
tower. The sulphur. coming from the stove as
gas is liberated "A the bottom Of the towers, and
There stages at certain intervals IN eacn tower
and upon tlese the marble. broken into small
descending water and II is the meeting OF these
two with the lime that forms the sqlphuTous acla,
sgeefers g3ere he schips are cooked the said
c5}-s Fefn- he small pieces into which the pulp
Wood fas been broken. or chipped, By machinery;
orls mo 7te Irei.trati9n OF the wood up this
stage SEpIosing IL 10 have arrived al ile I'M
Inch il into TWO foot lengths; then the bark
zol1stions Ter minute and having automatic feed.
- gaJches that hold and turn the log against the
t - - ir,s Which revolving at great speed cut
which. however, they are sent TO the crusAeTs
20 be REDUCED IN size. and then 10 the chip screen
a rotary affair where the wdust is gotten rid OF
This screen IL constructed thus. The hTsl section
is Of wire through which the sawdust IS thrown On
by centrifugal motion. tie other portion OF the
rotary being composed Of steel plates with slots.
Through which the good-as 70 Slze-chips pass,
the balance beng retained by the In9Ghlhe Tor
wood l. used. the cooking takes everything but the
lbre af which TheTe Is left about - per Thus,
nile iu ground wood about 300 pounds Of pulp
WOOD is obtained from cord of wood, because
both the cellul0se and utcrcelular matter pre-
served. The only loss being il the mechanical pro-
cess Of removing the imPerfectly ground wood. the
sulphite process Yields only about 100 This sui
phite is really the binder for the ground wood.
and gives 10 the paper made from II greater
strength and a better surface
The digeSters are vast hgtte-shaped tanks Of
steel, lined with tile and cement. and having a
nzclty % some cords OF wood each. Into the
open throas of this giant bottle IS inserted huge
wooden hopper, through which the chips, falling
from tie aO.- above. fed into its a
lis neck or. The feed floor the pipes conveying
the acid also the dgester. This last rests
steel columns. which support its base
threc or four feet above the concrete floor Of the
cellar. the space between which and the feed floor
above f. divided into several decks tsCaffod
platfornsb from which the several portions
tested steam. under pressure. is forced into the
ruTiCal - TIE algeSerS. through their
contents the acid descends into them This
cooking operation is q delicate one. temp, nature
steam pressure and acid strength have 10 be very
carefully watched and regulated TO obtaia the de-
sired results. The steam pressure IS put at
first - TO lGa pounds. and Il IS necessary to be
careful that the temperature Is too high An
even circulation Of the acid throughout the OF
chips IS absolutely necessary. and u is the steam's
Office effect this. After the chips have cooked
from eight 10 twelve hours the digesterS deliver
them into the 'blow-pit." big wooden tub with a
perforated bottom. which lets the acid down. water
being added 10 assist the drainage. This leaves
only the pure fibre In the tub the disintegrated
resinous matter having passed of. with thu acid.
70 waste The blow pit has diameter or about
<~-A@I< faei-and about the same deDth-and holds