Sulfite pulping experiments on sand pine


Material Information

Sulfite pulping experiments on sand pine
Physical Description:
McGovern, J. N
Keller, E. L
Forest Products Laboratory (U.S.)
University of Wisconsin
Dept. of Agriculture, Forest Service, Forest Products Laboratory ( Madison, Wis )
Publication Date:

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All applicable rights reserved by the source institution and holding location.
Resource Identifier:
aleph - 29316862
oclc - 755903028
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Full Text
,,. S. r OES SE"RVCEf
t 0 ;H E
March 1943

No. IP1429
Madison, Wisconsin
In Cooperation with the University of Wisconsin


^ULFI Tz PUL I :", '2 E7, E- I T-- CON, S A:D 0 IF

J. GOWUAzf-ociatc T-chnolojgis-t
~. KLLE~,JuniorChit
S1umma ry
3 -veral r-n ine (Pirus -, sa bolt:- w.i-th anaerg eniy f.
pounds pr cut-c 'oot average gq :row t h r ate of' 9.6 rng per.7 r nir-c'n andi- ave-r -
age heartood volume 0o. _55 percent, were -te ito heairtoodi and
- ,-wood for ufit pulping -xperiments. The, sppwiood h-a-d ceia hr
ei -tic- iia to thosp of the whole wood of --r.- pine -.rle -Y vou ly
received a t the~ Forest PrdcsLaboratory, whra h- heartw.,ood w Fi on d
to b~low in lignin. and cellulose contents -and exceptionall'Iy high i*r matze-
ri-cl1- --oluble in alcohol-benzene., ethe-r, 1 percent s-odllium h.yldroxide, and
hot zwater i.
Tis: nr., moderate pulping conditions, the -- wood chp wr completely
di~~sedto a low bleaching pulp, but the heartwovodchip wer icompetely
rAucd two-thirds of the total fibrous yield of' 57 pretbcm ce
~nr ejets. Application of a relatively low maxiu epe-u, n
l -r. digetion time improved the heartw.ood pulpingsmehtbt vn ne
the rifvo-,ible conditions the scr- eninp_ rejects aone to tw:o -f1'th- te
Thesapoodpulp of' -and pine had q chlorine- dean o only 29pr
~ert, ad uchlower streni-th propertiesta sapwV~ooC puIPS obtatined fro
o0+e ouhrn pines and -ais high in celluloFe rn nr-th-r hi-i ther
w r x t or a l r o 1 eh t n e x rs h ch min co s it e t of -Ind
-"..,od rn h -r:ood pulp we re con.sI.-,t-nt 1'ith the of0 0 h* cis ef
Introduce ion
Sar.U" pie i Tarmior n.-)r.17r of' I--- uter yellow, pine goigin
rlrd adAabin. tn of -and pine of s-orre -CO ords:, pl
of -porin r x nua u o:f 4 -,GOO crif or a 5-ea rotaItion', grows!- in
th~ Ocala N~rioral Forst in northcentral olrid. I ~ i elme
;alu~~~~~~~~~~~,T, Iu r~d oeote ~suft up e n

0. _0.

Ruel reported that sand pine could be readily reduced by the sulflte
process to bleachable pulps in the yield range of 25 to 35 percent. Th.i,
appears to be the only reference available on the sulfite pulping of" t1hi!s
species. The possibility of making a wide variety of kraft paper- includ-
ing wrapping, high-grade paper, and newsprint was recently reported.2
The limited investigation reported here was undertaken the ees
of the Ocala National Forest to determine the feasibility of pulping sand
pine by the sulfite process using commercial conditions. The experiment nts-
were conducted on separated heartwood and sapwood samples and included:
(1) digestions of both the heartwood and sapwood under moderately mild pulp-
ing conditions and (2) a digestion of the heartwood using a rather low
maximum temperature and a long digestion time.
Experimental Part
Six 4-foot bolts of sand pine arrived at the Forest Products Labora-
tory from the Ocala National Forest on June 24, 1942, and were designated
as shipment No. 1667. One badly decayed bolt was discarded. M ost of the
outer bark of all bolts had. been knocked off during shipment. The inner
bark had been penetrated with borers and beetles and serious blue stai n
extended to the heartwood. One-innh discs were cut from the center of, each
bolt for the physical tests. After the bark had been completely removed
the wood was separated into heartwood and sapwood portions and converted
into 5/0-inch chips. The two kinds of chips were sampled for chemical
The digestions were made in a stainless-steel autoclave with R steam
jacket. Its capacity was 1.5 cubic feet. Tghe pulped chips were defibered
in a stirrer and passed through a diaphragm screen equipped with plates
having 0.012 inch slots. The digester charge was 15.3 pounds for the sap-
wood and 16.8 pounds for the heartwood, both on a moisture-free basis. The
acid charge was 7.0 gallons. Other digestion conditions are discussed later
in this paper.
Results and Discussion
The Wood
The bolts ranged in diameter from 7 to 9 inches. 'The physical
characteristics of this shipment were similar to those of a previous ship-
ment, No. 1375, except for a somewhat higher density, as shon in tbl- i.'
The higher density figure was within the range of densities for most southern
pine s.
'ells, S. D. and Rue, J. D. U.S.D.A, Bulletin 14-85 (1927).
-Bray, :,T. IAV. and Martin, J. S. South. Pulp & Paper Jour., June 1942.

Mimeo. No. R1429


'Te heiclcomprosition of tho sap-wood from shipmentt 'No. 1667,
givn i tale howed goodl ajr-mn with that- of t'he- whole wood from
.hipme nt No 35 atog hipme.:nt ',o. 1375apeae to 1-uu~a~ low
n nsn~ CAnd ether extractie matePrial. Thc ?heartwo fror No, 1667
c e czr a' I from ,ts wnspwo or the whole ood of' th pr~iu
~hipient. wa~low in li,;nin and_ alphn. and-oa ells~cnet n
i-hin material xtranted by -'oolbnenehe, ecntsdum
!h.'dro)xide, and, hot water. The high causticsouil* vle n-ctd h
prseceof de(:cay but none was detei ted vi:;ually.
l'ulpinrg _-xnrriments
Fecusethe rhysical and ch-ri--l characteristics of rpeioc ship-
mmrnts o:' 7,and pine were ,imilar to thcoe of northern iAck pinon Fim
oanksianrr ), pulping conditions ]cno,,-,r to be farystsacoyfrjc
pin,:- were used for the first experi--r-:. Th I an --c'tion of th--- mod-
Prqt,71Y mild conditions to the sand p-ine zqT-,oodr,1 ute in cmlt up
.ni, and a very low; bleaching pulp. Thsi hw y i-t o 3~-
in. table 3. The screening rej--ts of approximat-ly 1 percent w r robpblly
lie to the presence of a small proportion of hert1o7 he Z -p.od pulp,
whic wasslihtly overcooked, ha eypoor strength proprties-. a
muhwekrthan sulfl.ite pulps from othe-r southe r pines. It WaS hg in
Coth total ce~llulos,: and alpha cellulos-7 content. A Chrcr.trto
father :-oluble aera than desirable for sa-tisfac'ory PAper making a
prp:sent. :t does not appear from these, results that the sawoevon if
it ',an be readily obtained free from heartwvood, i,- i promiz4-nF ma.terial.
for sulfit- pulping under stsnda--rd conmerciAl condition:.~Ti dpes notL
rrecludp the possibility that more suitable pulping 'c ondition:- cain be
vrlopod to improve the qualities of the sapwood Iup
7he heartwood, when digested under the conditions 's- or tesp
wood, was not successfully pulped, as shown by the data for Nio. _F7-Y In
table 3 Th bi3,.lfite in the -ookin;- liquor waPxhau,-te:d about hor
Z' than in th- sapwood digestion, indicating- the pro -,r -, of hbi
S'ilfitp-dostroyi- omponents that are typical, of rine hes~rt %ocd. h
eyhaustion of t'e, biSulfite and (-onsePquently, t ,e horterc ,-,- pn tn
cP-uied 4 ncomplet, pulpinr Pnd gave -vid ,n e of an Pxtr.m-l. efaor
rr.teral.Approximately-, tw-o-third-, of the total fro yifld w~i h
4orm of scre,-nin ;s. The screened heartwood pulp ras hirgh In giad
~xracIvesand low in total. and alpha cellulose (,tale 4). irc~oe
a nhbl,,ach requir-ment. as Showr by-he -hlorinp requirement in
VYl .It was very weakrl from a paper-making -,tandroint (tab'Ile 4+).
Since a low maximum temp,-rature is known to be, faivorable.
.-n the p'llpirng of refract7ory h-e rtwoois,
~ or~d dpest:~n Pas maie of the he-,rtw:.oo, i: .-.hi-h temxmmtmea
>~~~re- :, ,resdfrm.3' to 13 C. Th- Ihnelwrd h eo
~~~771 hor-JTda mll pro~mn 0n th -1-r-h opuig Atouh the
cr, ret w:er- half fi-uc as znth firs: hertOddgsin

No. P141"29


they still amounted to two-fifths of the total yield. The chlorine requirP-
ment of the pulp was slightly lower than for the first heartwood aigetor.
Slight improvements in strength properties and chemical purity wer-
realized. The pulp, however, was still inferior in quality.
The sapwood from a small sample of sand pine was completely ruired
by the sulfite process under conditions comparable to those of corercial
practice; under similar conditions the heartwood was only partialpy rulyed.
The pulps were decidedly inferior in paper-making qualities compared to
sulfite pulps from other southern pines. Therefore, sand Fine is not
indicated to be a promising source of sulfite pulp as ordinarily prepared.

Mimeo. No. R1429


Tabe l-~~ysial ~raterst~s o sad Ii
of T7,~ n, e
Diameter~~-l (7 heg.....3755.,: ,4 .
------------------------------------- --------- ---------?
~rot~th rste che, s . . . . . .i ~12

anl erd~ o of sn

Shipmnt1667 :Sh--*Tm. 13t
:S a 7 % o -- : -- rtvw o d ,-olp wood


D 'nsit (pounds, per cubic foot) ....:


77, 1

-i ivrrl ,-'or 5g bolt, none ltini~ tcy

-Civr,-ry '-riht and Ereer,'7jL~
Tat'le 2--Chemical anfilysf .- o- h sapwood
p i n p

211.0 : -
iiS, o
35 (~


ii~~i n ...........
T~t;i ........, .. :

'V-M,1 0. No. Ri2

Table 3--sulfite pulping of sand T)Ie capwood and heartwood
Digestion: Wood I Cooking Penetration Cooking :Total: Yield
acid : time
SKind :Dryness:Total:Comb,:Time to:Time at:liax. :Time to :Time at .: Chlorine
202 : 502:110* C. :1100 C. :temp. :max. temp. :max. temp.: :Total:Soreenings: requirement
Number : Perce:Per- :Per-. h~oura Hours OC. Hours H Jurs :Hours:Per-. Percent Percent
G ent :;Zent: 5j _ont
381-Y :Bap- 69.4i 6.76:1.35: 1.5 2.0 :136 : 5.2 :13.2 .46.2 : 0.9 2.9
390-Y :Heart-.: 76.1 6.37-1.35*: 1.5 :2.0 136 83.3 :11.3 :56.9 3 4 : 16.3
wood ..
382-Y :Heart-: 76.5 t7-10:1.36: 2.o0 2.0 :1320 10 4L 45 5. 19.9 12.6
*wood .
Table 4-EhysIca!L roperties and chemical analyses of sand pine sapwood and heartwood sulfite pulps
Digestion: Physical properties of Iteaten pulp test sheets--25 by 40 500 ream Chemical analyses
nu brn- - - -- - - - - -- - - - -- - - - - -- - - - - -- - - - - -- - - - -
and :Bursting strength:Tearing strength:Tenaile strength: Solid fraction Beating time :Lignin: Cellulose : : Solubility in--
material: --------- ----------------- -------- --------.:------- : Total : ------------------
:Freeness-S.R. Freeness-S.R. :Freeness-S.R. :Freeness-S.R. :Freeness-S.R. : :Total:klpha:pentosans: :Alcohol: :Ash
80 ---- 0c.:0 c: 5 c 80c. 50c.:0 c 50cc 80c. 5 c:---------------------------- ---------------- ---------------- ---------------- : :Ether:bentene:NaOH:
Pts. per lb. :Gm. per lb. :Lb. per sq. In~ : Min. Per- :Per- :Per- :Percent :Per- :Percent:Per-:Per-
per ream per ream : : ent : E:ent :cent :cent:cent
g8l-Y : 0.36 20.39 0.75: 0.50 3,600: ',6oo o.4~6 :0.55 :17 : 40 :0.8 :96.o :so.4 : 4.6 :2.2 :2.5 :g.I4: o.14
Bapwood :
380-Y : 27 : 32 .6o .140 :2,100 t3,700 : 37 : .145 : 27 9.0 :714.2 :61.1 : 4.o :15.2 :16.6 :25-7: 0.9
Heartwood: :
a 92-Y : .29 : 37 : .65 : .145 2,200 : 4,100 : 37 : .146 :15 414 8.1 :75.5 :614.o : 4.o :15.5 :15.8 :22.7: 0.8
heartwood :
z M 4606r, F,

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