The grinding of hardwoods, studies on swamp tupelo, paper birch, green ash, sugarberry, southern cottonwood, black willo...

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Title:
The grinding of hardwoods, studies on swamp tupelo, paper birch, green ash, sugarberry, southern cottonwood, black willow, and American elm
Physical Description:
Book
Creator:
Schafer, E. R ( Earl R )
Pew, J. C
Forest Products Laboratory (U.S.)
University of Wisconsin
Publisher:
Dept. of Agriculture, Forest Service, Forest Products Laboratory ( Madison, Wis )
Publication Date:

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Rights Management:
All applicable rights reserved by the source institution and holding location.
Resource Identifier:
aleph - 29300944
oclc - 223404020
System ID:
AA00020548:00001

Table of Contents
    Front Cover
        Front Cover
    Summary
        Page 1
    Introduction and Swamp Tupelo
        Page 2
        Page 3
    Paper birch
        Page 4
    Green ash, sugarberry, and Southern cottonwood
        Page 5
    Black willow and American elm
        Page 6
    General considerations
        Page 7
    Literature cited
        Page 8
    Tables 1 to 8
        Page 9
        Page 10
        Page 11
        Page 12
        Page 13
        Page 14
        Page 15
        Page 16
    Back Cover
        Back Cover
Full Text



TN-i CIINUING ()If HAIUWCDUS
August 1942
It












OA




AL_




L) DEPOSITORY



UNITED STATES DEPARTMENT OF AGRICULTURE
FOREST SERVICE
FOREST PRODUCTS LABORATORY
Madison, Wisconsin
In Cooperation with the University of Wisconsin
I









THE GRIINDING OF HARDWOODS


Studies on Swamp Tupelo, Paper Birch, Green Ash,
Sugarberry, Southern Cottonwood, Black Willow, and American Ilm


By

E. R. SCHAFER, Senior Engineer
and
J. C. PEW, Associate Engineer



Summary


Investigations of the grinding of hardwoods have been conducted at the Forest
Products Laboratory over a period of years with results that should be of
interest to manufacturers of papers containing grcundwood, who no'.: obtin
suitable softwood species at considerable dictanceL fro= their mills. Hard-
woods, by their ready accessibility to many mro Ji'r, od mills, offer distinct
advantages from the standpoint of pulpwDcQ trOnscprtation costs. Increased
use of hardwoods would also aid in the improvement .f Lixed stands of hard-
woods and coniferous woods, and would expand our pulpwo:d resources.

Swamp tupelo, if ground soon after cutting, yields a groundwood pulp that is
litht colored and short fibered. It lacks the strength considered essential
in the pulps produced from spruce and other softwoods but, even so, can. be
used in appreciable quantities as filler stock in the manufacture of book,
magazine, and newsprint paper. Groundwood pulp made from parer birch has
similar properties. The absorbent quality of this pulp was demonstrated in
the production of a highly absorbent toweling paper. The pulps made from
green ash but not so strong as standard pulp made from spruce. Satisfactory newsprint
papers were made, however, in which both species constituteJ a considerable
part of the furnish. The groundwood pulps obtained from southern cottonwood
and black willow were comparable in strength with commercial ground'-ood.
Although the color of the latter is too dark to permit its use in newsprint
or other light colored papers, it should be suitable for papers and boards in
which the dark color is not objectionable. Groundwood pulp made from American
elm was both short fibered and dark colored, qualities which limit its use
to such products as filler stock for boards and papers of low color.

The energy consumed in the making of groundwood pulps from hardwoods need not
be so high as is generally believed necessary. For many purposes a sstis-
factory groundwood can be made from these woods with less energy than is
ordinarily consumed in the grinding of softwoods. Some hardwoods, moreover,
yield more pulp per cord than can be obtained from the softwoods.


Rl419





he United States
ve been com-
sed cost of
. The spruces
ip, with the
r. The idea
of the hardwood
s. In fact,
ss. Increased
a wartime
iso as good
stance, in-
e conducive to


e amount of
all. Thickens
and black
energy con-
roundwood.
to two-thirds
editions.
er freeness
s, according
ts that the use
tter for the
moderate pres-
nd that beech
round'-rood was,
ure of beech
eign investi-
erican ob-
in improving
ion per ton,


iucts Laboratory
rdwoods. This







received and again after treatment with sodium sulfite solutions, In all
experiments on untreated wood, the pulps obtained were low in strength and
average fiber length as compared to standard spruce groundwood. The pul
obtained by grinding on a dull-surfaced stone and with high pressure were
completely fibrillated and slightly stronger than those obtained with the i
of sharper stone surfaces.

These swamp tupelo groundwood pulps had an excellent color. The color of
grounxdwood pulps obtained in other experiments was found, however, to be ii
fluenced greatly by the conditions 'of storage prevailing prior to pulping c
the wood. It has been pointed out in a previous publication (1) that the
light-colored sapwood in the freshly cut wood became discolored in less th
2 months if stored in a warm, moist condition, such as might prevail in
southern climates during the summer. The fresh wood did not discolor if
dried rapidly, indicating that moisture was an essential factor in the dis-
coloration. Pulping the wood soon after cutting, before discoloration can
occur, would appear to be a desirable practice.

The wood was chemically treated before, grinding to improve the strength an
increase the average fiber length of the pulp. Most pretreating processes,
however, discolor the wood, and this discoloration, of course, prevents th(
use of the groundwood pulp in light-colored papers. Since the neutral sull
solutions used in the semichemical process of treating chips do not discolc
the wood if properly applied, the liquor used in these experiments was of I
type, i.e., a mixture of sodium sulfite and sodium bicarbonate. Log sectic
about 2g inches long were weighted down in a treating cylinder and covered


to 170 C., the
obtained. r
ture during the
romn the treated
method was groi
* 4' ,.rc t- BY'IA W9


lightly higher weight, but otherwise equal to
,r experiment in which 50 percent of the furnis
tood, 20 percent of slash pine groundwood, and
Spulp, (machine run 350) had normal strength.
mundwood content was reduced to 50 percent and












Acceptable sheets of book paper were made, in which the normal component of
ioda pulp was substituted in whole or in part with tupelo groundwood (machine
runs 339, 441, and 442). These papers possessed good color, finish, and
strength. One of the papers in this group (run 340) was, except for its low
bursting strength, typical of rotogravure paper in its properties.

%he papers having treated tupelo groundwood as part Of their furnish were
rough of surface and weak. Further study of pulps of this type is necessary
,o learn more about their papermaking characteristics.


Paper Birch


Paper birch (Betula papyrifera) is an important northern hardwood. It ranges
'rom Labrador to Hudson Bay, southward to Long Island and northern Pennsyl-
vania, and westward through Ontario, Michigan, and northern Wisconsin to
western Minnesota and eastern Manitoba. The wood used in the experiments re-
Morted here wad obtained from northern Wisconsin and Michigan. The grinding
.ata are given in table 4*

'he pulps produced were, in general, like those from the swamp tupelo; short
'ibered and low in strength, but, in spite of their short-fibered character-
Latics, quite free. Increasing the pressure of the wood on the stone surface
rom 20 pounds per square inch to 30 pounds and then to 4O pounds, successive-
.y, reduced both the strength and the unit energy consumption. Freeness
ras increased, but there was little change in fiber length. Contrary to
experience with softwoods, raising the pit temperature (without change in
consistency ) produced a negligible effect.

although the birch wood, especially when green, is quite white, the pulps were
inclinedd to have a more or less pronounced orange tint. The coloring matter
Appeared to be water-soluble, but showed a tendency to become adsorbed on the
ulp to some extent when standing in suspension. A sample of the pulp washed
immediatelyy after discharge from the grinder was decidedly improved in color.

'he properties of the birch groundwood described above did not bar its use
.n several types of paper. Table 5 shows data for newsprint paper. When
omblned with birch neutral sulfite semichemical pulp and a coniferous ground-
food pulp, birch groundwood may be used in Iroportions up to 30 percent of
'he total furnish with satisfactory results. The 50 percent of birch semi-
:hemical pulp used with this amount of birch groundwood brought the total
hardwood content of the sheet to 80 percent. Comparing the properties of the
experimentall papers with the averages for commercial newsprint papers, it is
Loted that nearly all of the experimental -oaers are equal to or better than


11419


faU 1OLJ I ft _U01W U W L" i W A. 64 I LWA WU. Q Gbi k V* 1~W








Certain grades of toweling paper contain from 40 to 50 percent of groundwood
pulp, usually made from spruce and balsam, the remainder of the furnish bein
spruce sulfite pulp. The short fiber, softness, and apparent absorbent
qualities of birch groundwood suggested its possible use in this grade of
paper. The principal data obtained in several experiments in the making of
toweling paper are given in table 6. The birch groundwood was substituted
for part or all of the spruce groundwood in amounts varying from 15 to 45
percent of the total furnish. The birch groundwood lowered the strength
slightly, but this was overcome to some extent by a little beating or Jordan-
ing. The drainage from the wire was slower and the wet strength of the web
before passing the creping doctor was lowered. Considerable picking occurred
on the dryers. In commercial operations these machine-operating character-
istics will need to be controlled by appropriate countermeasures. The water-
absorption rate of the toweling paper was greatly increased by the addition
of the birch pulp. One of the best papers, meeting most of the strength re-
quirements of the standard toweling paper, contained 25 percent of birch
groundwood (machine run 1707). This paper had more than 3 times the absorbed
of the standard.


Green Ash, Sugarberry, and Southern Cottonwood


Green ash, sugarberry, and cottonwood were received and tested at the same
time. For this reason, it is convenient to consider them as a group. Geen
ash (Fraxinus, pennsylvania lanceolata) is widely spread throughout southern
Canada and the United States as far west as the eastern ranges of the Rocky
Mountains. Sugarerry (Celtis laevigata), also commonly known as hackberry,
is a bottomla&-l hardiwood growing in the southern United States, being quite
plentiful in 'he Mississippi valley. Southern cottonwood (Populus del.toldes
virginiana) occurs i. river valleys throughout the eastern, southern, and


delta region of Arkansas.

The grinding data are Riven in table -7 which includes


data on paper birch and southern piie and
print groundwood pulps.

By lowering the grinding pressure on the s
square inch of w-ood on the stone surface ti
little but a large increase in energy consi
the pressure _aS raised to 40 pounds, on tl
of strength was produced and' both a marked
erin of energy consumption were achieved.
to that with ugarberry, except that the ii
unit energy consumption only slightly.

Comparing the groundwood pulps produced at
apparent that the unit energy consumption
the range of commercial practice for news
sugarberry being somewhat high. The fiber


average val


igarberry f
ie pulp str


The
crest


30 pounds pei
for these thi
int groundwoc


for comparison purp
s for commercial ne,


m 30 to 20 pounds p
gth was raised a
on was attained. W
, very little lower


asrt
redux


Sinch,
.woods
That








the commercial groundwoods and slightly shorter than those of birch pulp. The
cottonwood was low in the coarsest mesh fraction (24-mesh), but otherwise
approached commercial pulps in screen analysis. The sugarberry and ash had
only fair bursting and tensile strengths and poor tearing strength. The
cottonwood equaled the commercial average in bursting and tensile strength,
but was somewhat lower in tearing strength. The sugarberryj ash, and cotton,.
wood were all superior in strength to the birch groundwood although none was
as strong as the southern pine groundwood. All of them were comparable with
spruce groundwood in color.

These hardwood groundwood' pulps were used in newsprint papermaking ex-eriments
with southern pine groundwood pulp and semibleached southern pine sulfate pulp.
The data are given in table 9. On the basis of machine runs 1770,and 1771,
it' was found that a furnish containing 20 percent of cottonool groundwood,
60 percent of pine groundwood, and 20 percent of pine sulfate, lightly
jordaned, gave a paper about equal to the average commercial newsprint. TIM
whiteness, at 65 percent, was very good. When the cottonwood groundwood
content was increased to 40 percent (machine run 1772) and the same total
groundwood content was maintained, the tensile strength was lowered about one-
fifth, but there was practically no change in bursting strength. The tearing
strength was higher than the standard average.

The relative effect of the three hardwood species may be noted by comparing
machine runs 1772, 1773. and 1775. The paper of run 1772, containing cotton-
wood groundwood, was about equal in quality to that of run 1773, which con-
tained an equal amount of ash groundwood, while the paper from run 1775,
containing sugarberry groundwood, was poorer. Machine run 1777 was made with
a furnish consisting of equal amounts of the three hardwood grouniwools, 39
percent in all. The rest of the furnish was pine groundwood and semibleached
sulfate in about the proportions used in the three runs just discussed. Vith
the exception of tearing resistance, the test values for all strength proper-
ties are less than the average for commercial newsprint. In these newsprint
experiments it appeared that at least 20 percent of semibleached sulfate pulp
was required to bring the bursting and tensile strengths up to values cord-
parable with commercial newsprint. This amount of sulfate pulp produced a
tearing strength higher than the standard. Although none of the har'wood-
containing papers were quite as strong as the average for pine groundwood and
sulfate alone, they are considered satisfactory for use as newsprint paper.

Summarizing these experiments, it is indicated that groundwood pulp of
acceptable quality can be made from cottonwood, green ash, and sugarberry.
In the making of newsprint paper, these pulps can be combined, in quantities
as high. as 40 percent, with southern pine groundwood and semibleached sulfate


SOU1









samples tested at the Laboratory were received fr6m the Arkansas delta r on
as were the three hardwoods discussed in the foregoing section. The data e
given in table 7.

The black willow groundwood, like the cottonwood, was low in the 214-mesh re
fraction, but wase about equal to the commercial groundwoode in strength. The
elm groundwood was more like the sugarberry in fiber length and strength.
Under comparable grinding conditions, the energy consumption for the elm was
higher than that for the willow, which was normal for groundwood of newsprint
grade. The dark color of these puips was their principal defect, and it was
for this reason that papermaking tests were not made with them. It is entire
possible that willow and elm groundwood pulpa 'e,'be used in papers and board
in which color is not so important, as, for instance, in insulating board or
container board filler, but no experiments were made to ascertain this.


General Considerat ions


It is generally believed that the production of groundwood pulp from hardwood
requires a high expenditure of energy. This is often true when it is soiugb
to produce pulp comparable to spruce groundwood in strength and fiber length.
In fact, it is doubtful whether these properties can be obtained with such
dense, short-fibered hardwoods as tupelo, birch, beech, maple, sugarbegg,f
ash. There are uses for groundwood pulp, however, in which the strenagtlng
normally obtained from spruce are not necessarily required. The data in
tables 1, 4, and 7, give evidence-that pulps satisfactory for certain purpose
can be made from this class of hardwoods with average or below average energy
consumption. Hardwoods of lower density such as cottonwood, aspen, willow,
etc., yield relatively free groundwoods with average strength and normal ener
consumption. The fiber length of these groundwoods is, as a rule, somewhat
less than that of spruce, and the color of some of them limits their field of
usefulness.

Because of the short fiber of some hardwood groundwood pulps, considerable
difficulty is experienced in attempting to form laps on the wet machine in tb
customary manner. It might be better, in such instances, to take the pulp
off the machine in loose, crumbled form and store it in bales instead of laps
Better still, perhaps, would be the use of a slush system entirely when
grinding hardwoods. Close attention must also be paid to the prevention of
white water fiber losses when operating with hardwood groundwood pulps, by
providing a properly closed system and adequate oave-alls. Some mill operate
have abandoned the grinding of hardwoods, for the reason that low yields were
obtained. A modification of the wet machine operation and white water system
might have been a solution to these difficulties.

Some of the hardwoods have fairly high densities in contrast to the softwoods
usually used for eroundwood manufacture, The resultant higher weight of wood


-1 ,







exception of cottonwood and willow, ranged from about 2400 to 2700 pounds of
oisture-free wood per standard cord. The cottonwood and willow were compar-
ble with spruce in weight per cord, namely around 2000 pounds. In these days
f uncertain transportation, it might be advantageous to procure hardwoods,
yen at a higher price per cord, in stands close to the mill than to purchase
oftwoods at a lower price, but requiring a longer haul.

Literature Cited

L) Benninger, Fritz.
Groundwood from beech. Woohbl. Papier fabr. J2:11g-120 (1941).

2) Brecht, V.; Schrotter, Hi: Suttinger, R.
A comparison of various woods in mechanical pulp manufacture. Papier
fabr. (Tech. Wiss Teil) L6 4l3-420 (1938).

5) Briefkasten.
Groundwood from aspen. Wochbl. Papier fabr. 69 (33):622; (35):655;
(36):681; (Aug. 14, 28, Sept. 4, 1937).
4) Kin, Myron; Libby, C. B.
The manufacture of brown mechanical pulps from hardwoods. I yellow
birch. Paper Ind. and Paper World 22 (7):675 (Oct. 1940); (9):918-923
(Dec. 1940); (10):1043-10o4 (Jan. 19-1).

5) Hunro, W. A.
Poplar wood as a substitute in the manufacture of groundwoocl. Paper
Trade Jour. fJ (20):60 (iTov. 15, 1923).

6) Running, K. D.
Hardwood utilization by the paper industry. Pulp and Paper .1'ag. Can.
42 (2) 104-106 (Convention issue 1941).

7) Schafer, B. R.; Pew, J. C.; Pillow, M. Y.
Discoloration of swamp black gum pulpwood in storage. Tech. Assoc.
Papers 22:405-8 (1939).
5) Thickens, Ji H* and MclTaughton, G* C.
Groundwood pulp. UT. 9. Deptt Agric, Bull, 343 (April 26, 1916).

9) Wynn-Roberts, R. I.
Grinding characteristics of various woods. Paper Trare Jour. l1O4
(6) 46-49 (Feb. 11, 1937).































' ~ *.....4. s..;.. .t 'I .f~* t'*. To- i rr ;l *S.G.4fb ,
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11 1. LS L t 1.
di I. 1.1* >U f' * t l 1} l T 1 i* l !Sl < i ~ '* ;
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II-i6 T tef i I (r, ; ( H i T 80i ~ l ~ 0 .. 1 t.6 i Ii 61..'Ig *i i ae
a ..'. I1 0- so eI .5 I 33 ,10 .8 Pd l.Ia
0.in Ia s.>15 *t0-l02 B ..r -I td.J t. 15 asae p *;p *.. l t 1 106I I I .? 6.9 .7.0 t~ 71 *'Il 1.1 .*-. I* 5i ........ ( I i

da-~~ t^ " fif-*, 0 TJ .4.jd 4,*...,.,.. ,.... ..,. 1 ^ I B Il6; 69 .?! .8 i1- 1. 1.2 .10 .2. s- liS ..... 4..... .... a.* .,.

.I2 *^ ! U V ll; 1 *l. 0 I 1 >1 .U t 18~ ., M.t .a 1 l . )i- :*; :; -;
L'. .^ .i t l.. .... .. .; 1. I U6 "> 1.9 1.0~ l. at1S l ;'l *t . l.11 ls 1 it .,; <* l> o I
I i k, I de. 1 C. reda




.3 r ..5. V- i.....~... ., 61. 1 68 -i i .1) F. 03. I 8. ?. 5 fII O .x> .11,4 1... ~ 6 : 1: .30 a. a.. .5 a.
It 0.n-45t % s2' 501 ns*s S5. q lp.' 0.l> as 0p*.k 1.8 t.lst. Is 105 m23 1 15.,. 18 #p0S504 50 C* p lha I .p. -2 330 t*5 I S1.1i. l 1 I ,] ;* ~ i
1s ,. .*' .W a. T l A f-in *i *s. i~ la <1.at.. 0 b (*.r SO l 10 5.1 S l s}n.1- .Is ia C, 12 p01. d Is.!. 2. .t0 1 55.1 o ~l: 652 1 6 nIl t5. *I.L .45 10* 205 dl o5to i
7,.lon .s la 801 SISS i.50fa.... Th .. t5151 18 51* Il.i. l454.m 15 aI-s 7b sla 5,1 5..5 tos It l.C b. ts . ss *. .1 Is SB. b'l.1* a .. *n O..i 1 951!s 80fl 45 nD .9 BS t
n.'02 I I be,.





2* .tt: 1111.51 *fit *5 255 415 1 7 12. ss B*.oSS5 D 1.} p25455 02 18 .1125 ~ 15l p.2I.56 1 .541.6 t.> 455.? I f; .S .. ** 1; t } *
1 f5 i.4 0 s C,,854 1>.* (.. 1.... CI 12. 7*! 5. 5 fl.. <>..5 **l. 51 1.5 !, t Ia M~l i 500.** 0 i .. t i .* r ~~~P5~~13 6.,. 16. ........... ws ~ 8. ~a
"1^f i0 :V, 1*
^ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ t m2r rj .2 ; ",wi " i ii**- H.rr "l iit o i*
\9f WW ssa^^f w^#t sB(*t Kfft r tkbot~or


























Table 2.-COhooal treatment of se.on tupelo before arindinl


I I I I
Wood : Treating liquor I Impregnation Cooking
--- --- ----- --- -- --- --- --------------------... ... ... .. I -------------------- I; -------------------- I ------------------- -- -- - -- -
SI mount of rreeh U lOWbaok I spent O Chemiclal I
Dige.-.. Wood used. ovTn-dry mood I I t absorbed IDure Nazi-: alo-!rag IDurs-. Nxi- lJAvrage
tion Sl........... grind Lnt- -------------- -------..----------- I ------------------- MIon !mum t prre- ItIon IamI pros-
No. trun .l S or N dle* a ii In lOonoontrtion Conontratlon Oonoentraton: ------------- Item- Sure I Itb. i sure
Sbolts sta"r wood streatedVolume ----- 3--: volumeZ ----------- tVolum er.----.-. I per. I pepr-
a taken wood t S:.80 39 3i; 530 :3*2003: :3.82O SOf :t" 00 B,".s2003 ature : tur
t 2 : (I) i 2 3: () 2 3 (1) 1 2 31 (1) 1 ,
. .l.. a ... r.... r- . . .. 9........... t. For- I L. .. ... oure . ..... I. . 1 t .a.. .
1B a p1snmr Eo wr smr c0r car 11 Fr DF' I Ir

S I 5 IM -- S IB 1 182 2.2: :16:06:: 1 :a. 1.510 125Ta

2322.18, 19, 20: 90 .1 5.9 0 1 8 ....... 2.2 o0 13 01 2 1908 1.5 35170 7125
2l121. 1 27:17.1:65.2 8U.25 2:.2 l.8 9. :.... :6.....:39.6:1.8:5.6:?.60 .35:1 :01 l :170 10
M2?2: 28 27 3 7.-2 sa5 13.0 ..... ..9.. :61.7 6.1 : .47 3.21 S 952 185 :6 150: 72
2031 32 :27.5 6.2 Z.4 43.1 :.: 79.811. ... .. .... ...... 14.6 5.0 6.51.04 .. ......................
732. 3 3275.. . .. .9 15 ..... ...... ...... 39. 5.2 9.6 7 1.05.. . .....

reosnt s 3a00A but oalulatd A003.
A 'cyole* oonsiste of one VOuul am one pressute pbae.0


M 39203 P










Table 3.-Book and newsprint opere ont In1 wamp tupelo Kround-wood pulp


Mahlne: urnslBh Properties of the paper
Ho. : round wood Sulflte pulp : lze: Alum : Weight : Thick-: ursting: Tearingi : Ten- :stretch: Ahite-: Castor Opacity: loss
.-.-.-.-------- --.------------------------. per ream ne, : per pound per pound : slile,: :nes : oil
GriAnder: Anount: Srecles Nlo.! ; Amount: z: : x 4o per ream : per ream :break-: pene-
run :500 : : 25 x 40 25 x 40 : ing : :tration
No. : : : 00 :length:
:Percent ; :Percent:Percent:Percent: Pounds : Ils : Point Gram Meters:PercPercet:Percenst: eoonds :Percent:Percent
Newerint papers


S0 pruce 3443
70 Slash pine : 3449
70 .... do ...... 34557
13 bpruce 3474
5 8laeih pine 3456
70 spruce P-9 46
50 Slash pine 3452
3 ....do....d ... 345
50
20 ....do...... 3485
....do.....: 3485
50 ;B;a;p tupelo: 3481
70 :blash pine : 3)506
70 sprucee P-946
70 ....do...... .P-946
20 slIsh pine 3485
70 :....do...... 35o06
80 ....do......: 3506


30
30
30
27
35
30
50
30
30
15
35 J
30
30
30
30
30
20


1.0 : 1.5
.5 1.-3
.5 2.0
.5 1.5
3.0 : 4.5
.5 : 3.0
.5 3.0
.5 3.0
.5 5.0
.5 3.0
.5 7.0
.5 5:.0
.5 3.0
.5 3.0
.5 7.0
.5 : 7.0


Average of 56 oommerclal newsprint papers .........................

loot t~p&2r
1340 : 8 : 60 :Slash pine : 346 : 40 : .5 : 2.5
339 : 8 : 50 :....do....... 3446 : 0 : 1.5 : 3.0
441 S26 0 pruce : P-927 : 01:
2P_1.5 3.0
S 6 Sprdwoof : p-925 : 20 .0
442 ; 26 : 40 ispruce : P-927 : 60 i 1.5 3.0


3.2
3.3
4:40
4.0
3.1
3.0
4.0
4.0

4 .3
3.6
3.90
3-9
3.5
5.5


0.23

.17

.33
.20
.13
.16
.18
.10
.15
.13
.19
.15


0.57
.42
:48
.61
.53
.57
.63
.39
.48
.64
.24
.41
.36
.69
.66


38 : 3.3 : .25 : -54


4 5.5 :
: 4.5 :


3080 0.95 63 49 93 34
2090 : 1.15 : 62 : 70 : 93 : 34
: .. :.. ... : .. .. :... ....:....... :........
:1798: 1.12 : 66 : 26 '85 629
1615 1.25 64 26 : 21
3123 1.50: 14 93 39

1835 1-15 67 27 86 26
1205 1.15 68 11 : 3 : 29

:1378 1.10 70 : 8 : 84
1369 1.40 61 : 26 : 97 : 35
510 .75 73 : 5 : 7 :
1308 : 1.30 69 : 15 : 7 8
61l .50 70 10 81 30
2944 1.41 63 : : 90 : 35
1890 : 1.19 :62 2 90 : i
2795 1.00 59 : 50 : 9e : 41


:1480: 1.25 70o 42 : 90 1 26
2422 1.-25 76 : 80 ; 87 : ?9
2271 1.&5 79 152 91 35
2350 2.55 81 120 : 6 : 36


p, preceding the number of the pulp Indloates a commercial product.
LoT improve color, dye was added to the stock in the beater before adding alum.
To convert the bursting and tearing strengths of the newsprint papers to the trade ream base 24 x 36 500, multiply by 1.157.
4
-4ash pine ground-,wood pulp.
*Wood treated before grinding.
Surnlih for machine runs 339 and 340 contained 15 percent of olay based on total fiber; runs *441 and 446, 25 rent of clay.
A rotogravure type of paper.
ommerolal soda pulp.

Z1M 42$513 F


{153
10
14
15






25
3^1


532
i0
43



























Table 4.--Grlndlng of paper biroh



opertles : Grinding data : Properties of pulp suspension Propertles of pulp
'------------ --4 -------- ---------------------------------------- 4------------------------------- --- 4 -------.4----------------------
Den- IDry- i Preo- Stone i Ten- : Con- : XYield per 100 1 Dry :Power1Znergy:Freeness,: Screen analyssle Burst- : Tear- :Ten- :Solid:
sity. Ines s sure I serv- : per- s lat- :pounds dry wood : wood :Input: oon-:Bohopper-: -.-.----- ------------------------- ing per:Ing persles :frao-l.-.
dry :of t itoe2 :ature a enoy c ------------- groundd: : sumed: Rlegler : Re- I Retadned between :Passing: Fibertpound :pound : per :tion :!Jhi
eight : wood I of I lsoreened:oreen-:; per talned$ --------------- 150 lengtht per : per l:square
per I on I igrind- : pulp : ings : : ton : on t 24 it 42 i 80 mesh Index:rea :ream ; inch : I
green I atoneo : ing t: 1 : dry : 24 : and : and : and : :25x4:0 :25 I 40:
volume : : It ood I leseh 1 42 : 80 1505 00: -500: I
I ; : meahl mesh esh t : :
-:: : ------------------- -- I 4 -----------------:-------- ------ ------------
Lb r P ,i ._r Hours O te_ .FPer- Proent:Peroent T 2. H Go. :Per- Per-:Per-- e-.P :Percents :Point G-. : Lb.- PA
: c bent I I 1 1 I Fontsownt cent I 1 o<
; i t t It I : t i lt i | ; ;

29.6 78.8 28.8 17.1 1 160 4.4 it 91.3 O.E26 1.25 122 73 t 470 0.8 i 3.71 15.1 18.3 1 62.1 o.o72; 0.11 o.33 : 644 0.261
I It t ; l l : i
31.5 55.8 20.3 18.8 160 :3.8 i8 8.2 .27 .72 90 93 385 .1 1. -3 11.8 20.8 66.0 .068: .09 .30 644 1 .27t
I I I 1 8 1 I l 1 l t i : :
31.5 55.8 129.8 120.2 160o 4.3 1 92.2 1 .43 1.39 124 t67 t 475 t.1 2.3t 13-9 21.3 62.4 .069; .08 .25 528 1 .25:
i i i S : t I
31.5 55.8 40.3 20.8 16o 4.3 : 96.1 i .24 2.34 : 161 52 565 .2 2.4: 14.3 : 21.0 : 62.1 1 .0691 .06 .21 : 273 .23
I t I I t I I I I I I 1 1
31.5 55.8 29.8 21.2 190 :4. 8:89.5 .-37 1.31 117 67 510 .2: 2.9t 17.6 : 19.0 60.3 : .070t .08: .26 4a80 .24:
I 1 1 1 1 1 1 1
31.-8 5 6.5 40.0 t 22.0 16o : 4.6 1 94.1 s .31 2.07 : 153 56 i 520 .2 : 2.4: 16.5 : 23.8 : 57.2 : .075 .-07 : .20 : 314 : .23
I newsprint grade pulp ............................. ...... ..... ............. 65 ........... 7 0 ( ) ........ ........ : .......: .19 .59 : 945 ......

'oot (determined by calibration of the oyllnder pressure) divided by the area represented by the product of the pocket width and the wood length.
led. In previous service It had been burred with an 8-out, 1-1/2-mnoh lead, spiral burr, and after 58.8 hours of use, lightly sharpened with a 14-polnt dialmond burr. Tl
subsequent to thlls sharpening. The peripheral speed was 3150 feet per minute, and time of service was based on thls speed and the equivalent of 3-pooket operation.
lontaot area per 24 hours.
tometer. The tint Is designated as follows 0, orange: X, yellow; A, red.
k, 8 percent, and passing 60 mesh, 61 percent.























Table .--tem.,r! rit 1ac;irL c.: ritt I nE _bA rch ir,._ un_ __ ..- d _and r.rtfutrL1 dU1 fl t r


1iacnine oiren pulp
rn --------.-------------*----------|-
S. Ground Neutral eulflte
wood Cemichemlcal
:trinder:Amount Cook Amount:
;run No.: : No.

F er- :f, rc,-i it
zcrrdt

1659 : 377 18 : ,'7- : 31
3(75 j' 20 3^ N --" 0
l,3',,, 3 : 20 : i'.-N :
1317 : 21 : 1; -. : 0
1,U. 3 1,'7 : 20 : ,i-t. I ,3-1
1 *. ^ 2 0 ;'?;1^ 20
1721 : 3178 30 Y j-N :)0
1724 : 378 50 '--N : 0
l i'j 3 7 e 31'-- < 1 N -SO
17i3 378 : 0 A 1-N 40
i;1 : 37 :40 3920-N : 40

Average of 56 commercial newsprint Ipaper...


The jack pine was from grln.l-r run 361: the
To convert to the newsprint trade ream basi


Z M 4 71*i Fr


!'rcetrt



20
i ,-,
4>


20
20
20
3 c
Z 0




nercial g
, multlpl


S per ream: per ream
: x 4o 25 x 4o
'.,' : 500

HMilt lo1nt : Gram


3.5 : 0.24 o0.61


26
33
28
33
2b
21

79

















*0 L A WA'J*.%J1JU1JU. W JW V 0 - -
No. : :ing :

: Per- : Per- : Per- : :Pounds: Mils : :Point:Grams :Pounds: Per- : See-
Scent : cent : cent : per : per per cent :onds
:pound:pound :square:
: per : per :inch
:ream :ream

1702 ...... Nou :45.0 55.0 :None :None :None : 39.5 :10.52 :0.14 :0.21 : 1.09 : 525 : 4.65 : 263

1703 : 376 : 22.5 : 22.5 : 55.0 :None :Jor- :None : 39.8 :10.34 : .14 : .18 : -85 : 502 : 4.80 : 58
daned: : :

1704 : 376 : 45.0 : None : 55.0 :None :None :None : 38.5 :10.01 : .14 : .18 : .85 : 416 : 5.50 : 37















Table 7.-The finding of southern cottonwood, sogarborry, green men. black willow and Amerloan elm


3rieder: AvsrW~ prpoprtles of %he wood Grinding data Properties of pulp suspension Properties Of palp tset Sheets
-------- ---------------- ----------------.--------.------------------ --------------------------- ... .... ...... ....
Ag. Rot.. V D 811.. 1,Isl r-'r.. r on : Can- : l1.10 per IO0 Dry :Power: n-rgy F're .... Bereer. eanly.1s :b.rstilg" Tearing Ten. Solid Color a.-swielt.-
or 'r Jr, Y a r K -rd . ..... ,,j ...r.ds dry wood wood 1 IVVt A% o.. ...- ..... .... ..... ....... ......pe ......... p r par : all. :-f ........................
gT -owLhb.S15.- irl K1, t' en -.---------- rou;Fdi: :slned hle. r Retained Retained oetleea. plss- FIber pound pound per :tion Irhote.Pr -ir S.er,-
W-4 Lreen .t r.. :bocrwsn*dBoreow- : :per too: : on ----- -o- .t I 'ngtpor rroan per reanosquare: tint ary lnt
volume: pulp Ioge :dr : 211 uosh:24 andt:112 ad:80 aId: 10 ind.e P5 a 4. 25 x inc0: h zob
t wood : 80so : 150: mesh: n- 500 : 5W0 I
S ... ...... ...... .. ... ..... ........ . .. ... ....... - - - ------ --------------- ------ ------ ......- - - - -------- ...... ------- ------- -
____, ____e Kings P__r- _____no ____pn ______~us rre i pon Tons Up HpE~days Co Percent: Per- iPer- FoPr-: point (Ia LV4" I t !Per- pA Poi:~ roau


:3m 6.7 0 )c,.6 8 20 242 .1 :79. 4 :u.2: c, )6 : 11 18A, 10 1.:9.:0l 1 :xa0
do ... .1Z t.. .. ,, : ++ : ,.o
2j .3 2.8: .2 t 683.5 :. 300 .2 1:2 :9.; 15. b1 .10 .0b :5 06 .2 3: .7.-0
38 t D.:, do... o +.0, 0 :.7 15i+ I.+ is ,,.9, 3+,+, Ob5+ +" + + t + ';,o .,,
0re- Ash
386 41 8 't c 0 34-4s 66.?. 20 : .q2 : 3.7 :8$0.6: .11 .67:t83: 270 : .2 t:6.3 V-~7 s702: -W65 .16 : 1 91 i~ : 22j:71:3.-0: .1 A.
t8, : d 4 . ... do.. .d : 0 28 1 9 8.0 .0 2 1: 1 -3 .2 70 60 1 4 .-1
0eo+ +oo++. . :..:+. :;9 : .2 1+, :07 5- +
568 ~Do.:.do.:.o.:,d.... .d 1 29.11 4:1.5 a8 5 1811:13 1 352 :0 :03 .2:3 :2.: IN 190I 1 .2 tL"1 5_
Southern mottopwood
589 :26.011k.1:1 11.8: 23.6:1142.95 30 :30.2:s 3.7 :93.8: .3:11.331U3: 6: t1130 :1.3 :10.5 :22.6:16.5: 6.: .89 0610: .19: .1 -5:1050:t 425t:64t:51-0:1.6-?-

390 : 28.0:3 34. : 36.1: 23.6 t 4Z.2 30 131.0 :911.1 9 .30 :116 67 325 : -5. 7.2 t19.1 9 18.2 0.0: .0791 .-2: .50 t 1230 .-251 1 1 .?-7-0:0

391 : 55.t :8.1 : 22.8 : 29.-5 : 1173 30 :32 .3 87.9 .3: 1.09 :1114 781 : 22 M .1 : 2.7 111.0 : 13-.14 :t. .065: .16 : .11 : $01 2 $ 52 9.09-0" .t-M,
LAoleded for oomaerleOa

392 : 13.1: 3.8 : 0 129.3: 15.11' M4 : V t32.6: 11 12.: 9: 1.27 : 13 1 79: t3W : 7.0 :10 .11.6 : 12.6 : 55.81 .0601 .25 : .59: 116:1 .2- 66 4 .6.-0 t r."

315 ; 37.7:12.0 : ...... : A05 t 55,4 t 30 : 0o.2 : 1.) 92-.2 .1 1:.3519 2: 2 : 67: 1175 : .1 2 3. :03.9 : 21.3 1 1: .069: -06: .5:P5 528 : -.5: 67 1 :51-0 1 .-6.
A..U 4 F1 comrta.l noeerclnt 1rads rguOu l-Sood pulp@
....... !.+ .. . .+...... . .. .: ....... : .... .: ....... ......... I ........ : ....... ....... . 65 t ......... t 17.0 :14.0+ 3 (J) . .. ..+ ...... .19 !+ .59 t 91s ++ +...... ) ....... I ........

entua thrul st of the pressure toot determinedd by oalibration o1 the cylinder pressure) divided by the oar represented by the product of the pooket nnth ad the oo ength.
'k Mrton )160/5-N? stone em used. in previous erw e 1it Wd boon bwrred with an 6-cot. 1-1/2 Inob lead spiral burr end ofzer 58.8 hours of use I Lgtly sharpened with a 1In-point diamond ISOr. e hours glowsa to
this Column wmer tthe senl-e subsequent to this shlrpening. The peripheral Speed or the Stane Was 3150 toot per minute. LlIbough only two poets of the grinder were In use &% amt sr tine, the uti s4quwel t
Of Wee., Of the s ton srfane Is stliwated on the basls of tlree-pooket operation at this perlpheral speed.
37h.e temperature of grinding "e 1600 F.
*V1e square toot of woodosons contot erea per 2411 hure.
3tiolar souredd by Ive. tometar. The, tunt As deanee4 am o1osil 0, orargep T. yellow; A, red.
1Uigbt Iperent retained between 412 and 60 menh and 61 percent passing 60 eswb.

Z Y 4+2516 i


-----------


OW










Table 8.--Newsprint papers from southern cottonwood, green ash. sugarberry and pine


Machine: Ground-wood pulp : Semi- :Jordan-: Properties of the paper
run -------------- :bleache: ing : ----------------------------------------
Hardwoodl :Southern:sulfate.: :Weight:Thick-:Bursting2: Tearingl:Tensile: White-: Castor:Porosity:Opacity: Gloss
------------ : pine1 : : per : ness :per pound:per pound: per : nes : oil
Species : Amount: -------- : :ream : per ream: per ream: square: : pene-
Amount: : 25 x: : 25 x 40 : 25 x 40 : inch : tra-
:40 -: : 500 : 500 : : tion
:500 :
"-o------ ----- : ----:---- P 1-------- : P-----oin------ ----- -d---- -r---- ..------
No__. :Percent Percent Percent :Pounds Point Gram :Pounds :Percent:Seoonds:Seconds :Percent:Percent


1770 : Oottonwood : 20
1771 : Do......... 20
1772 : Do ......... 40O
1773 : Green ash 40
1774 : Do......... 40
1775 : Bugarberry 4: 40
1776 : Do......... 40
COottonwood t 13
1777 Green ash : 13
Ltugarberry : 13
Southern pine newsprint4


60
60o
40o
40o
45
40
45

41 :

80


20 None
20 Light
20 ...do..:
20 ...do..:
15 None
20 ...do..:
15 ...do..

20 ...do..:

20 :...do..:


Average of 56 commercial newsprint papers............ :


42 : 4.18
38 : 3.60

37 4.45
4o : 3.85
43 : 4.2l
41 : 4.06
4o : 4.26

39 : 4.07

32 : 3.34
38 : 3.30


0.22
.24
.23
.22
.18
.19
.17

.18

.29
.25


0.69
.57
,66
.64
.57
.61
.70

.70

75
.54


2,186
2,549
2,020
2,151
1,852
1,801
1,685

1,805

2,420
2,537


92
91
91
94
95
93
93

93

91
92


1
Species :Grinder
:run No.
Cottonwood : 389
Green ash : 388
Sugarberry : 395
Southern
pi.ne : '392
-In addition to the fiber furnish 0.25 percent of rosin size, dye, and alum to a pH of 4.5 to 5.0 was added. The semibleaohed pulp used
was prepared from commercial southern pine kraft bleached to a whiteness of 56 as measured by the Ives photometer.
To convert to the newsprint trade ream basis 24 K 36 500, multiply by 1.157-
4Average of machine runs -92 inclusive, 1148, 1149, 152-154 Inclusive.
"Average of machine runs 1088-1092 inclusive, 11148, 11149, 1152-11514 Inclusive.


Z U 42517 -


I





UNtVERSITY OF FLORICjA
3 1262 08924 5509
































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