SAIGONPAPER CORP.| 14 CNG NGH KH MC

Cng ngh kh mc

I. NHNG BC CHNH TRONG CNG NGH KH MC1. Quy btTrong qu trnh quy bt, x si c tch khi cc ph gia b sung trong qu trnh in n v gia cng. Nhiu loi thit b c th c s dng nh: quy nng thp, quy nng trung bnh, quy tang trng. Vic la chn thit b da trn cc thng s bao gm hiu qu tch x si, nng lng tiu th v cc yu t nh: ng lc tch x si Gim thiu ph v cc tp cht c th loi b chng hiu qu. V l do ny, thit b deflaker khng c s dng trong phn xng kh mc Tch mc khi x si mt cch hiu qu Ha cht (Kim, sodium silicate v x phng) c s dng trong giai on quy bt ci thin vic tch mc khi x si cho d xu hng gn y s dng cng ngh trung tnh. Peroxide cng c s dng trong giai on ny gim hin tng trng bt gim trong mi trng kim.2. Tch loi tp chtTp cht c tch loi khi x si da trn s khc bit v tnh cht: Khc bit v kch thc: tp cht nh hn x si c th tch loi bng phng php ra, tp cht c kch thc ln, nu chng cng, c th c tch loi bi phng php sng. Khc bit v t trng: Nu tp cht ln v c t trng khc 1 c th c loi b bng lc ly tm. Nhng thit b lc ly tm ny c thit k chuyn bit loi tp cht nng v tp cht nh. Khc bit v c tnh b mt: Tuyn ni c th loi b cc tp cht c tnh k nc. Cht hot ng b mt tng hp hoc x phng c s dng tp trung ht mc v tng hiu qu tuyn ni.

3. SngPhng php sng tch loi tp cht bng cch gi chng trn b mt sng trong khi x si i qua khe hoc l sng. Sng c th tch loi cc tp cht ln v cng nh nha, giy c bn t

4. Lc ly tm lc ly tm, chuyn ng quay c tp ra bi dng vo vung gc. Lc ly tm s chuyn cc tp cht nng (ct, sn, kim loi) hn x si ra pha ngoi trong khi nhng tp cht nh (hotmelt, cht dnh, plastic) s chuyn vo tm ca vng xoy. Lc ly tm c ln vn hnh nng cao l 5%, trong khi lc ly tm c nh vn hnh nng thp hn l 0,7% 1%.

5. Tuyn niTuyn ni loi b cc tp cht k nc (ch yu l cc ht mc) bng cch gn chng vo cc bng kh v a chng ln b mt. Cht tr tuyn ni c s dng ci thin qu trnh gn cc ht mc vo bng kh. Ngy nay, nhiu thit b tuyn ni c thit k ci thin qu trnh ha trn kh v loi b bt.

6. RaPhng php ra loi b cc tp cht c kch thc nh ra khi x si bi nc. Tnh cht a nc ca cc tp cht ny nh hng nhiu n hiu qu tch loi. Cc thit b c c s dng trong dy chuyn kh mc lun c hiu ng ra. Nhiu loi thit b hot ng nng khc nhau vi hiu qu ra khc nhau c s dng. Phng php ra c s dng loi b cht n, cc ht keo trong nc, cc loi mc b phn tn qu nh. Phng php ra thch hp cho vic loi b mc in flexo khi kch thc nh ca ht mc lm cho hot ng tuyn ni khng hiu qu.

7. DAFThit b DAF c s dng x l nc cng ngh ca phn xng kh mc. Mc ch chnh l loi b cht n, mc, cc ht dng keo c trong nc tch ra t giai on ra hoc c c.

8. Phn tnThit b phn tn c s dng rng ri trong dy chuyn kh mc. Mc ch chnh l phn tn cc tp cht, cc m mc ti kch thc nh hn mc mt thng c th nhn bit c. Cc cht dnh hotmelt cng c phn tn nh tc ng c hi ca chng c gim thiu. Tuy nhin mt s cht dnh t cc loi bng dnh hoc cc loi giy nhn t c kh nng phn tn.Thit b phn tn thng c kt hp vi ha cht ty. iu kin ny, ha cht ty d dng c trn u vi bt nng cao. S kt hp ny cng c hiu qu rt tt vi hin tng tch lng mc cn li khi x si to iu kin tch loi chng bi giai on tuyn ni sau.

9. Nng cp, ty trngMt vi bin php cng ngh c s dng nng cp bt. Thng thng, cc ch tiu c l khng cn yu cu cao nn giai on nghin c th c b qua. trng bt l ch tiu quan trng v giai on ty c s dng. Hydrogen peroxide (oxi ha) v sodium hydro sulfite (hoc FAS) (kh) c s dng rng ri trong ty bt kh mc. Peroxide iu kin giu oxi hoc ozon p sut cao c s dng ty bt kh mc t bt ha trng cao. 10. Kh mc giai on sau sn xut bt kh mc c cht lng cao hoc s dng giy loi c cht lng xu hn, giai on kh mc th hai thng c s dng. Mt s cng ngh cn p dng nhiu hn hai giai on kh mc. Giai on kh mc sau vn l tuyn ni, ra, sng lc. Thit b phn tn c s dng nhm tng kh nng tch v iu chnh kch thc ht mc tng hiu qu tch loi mc giai on kh mc th 2.

II. QU TRNH KH MCDy chuyn kh mc kt hp kt hp nhiu k thut nh ni phn trc. S giai on kh mc ph thuc vo loi giy ti ch v yu cu cht lng thnh phm. th biu din hm lng mc trong bt v trng ca bt cho ta hnh dung mc mc cn c loi b.

sn xut bt thnh phm cui cng, mt thng s quan trng l chi ph u t v chi ph vn hnh.Cc nh my c ch gm mt giai on kh mc c gng s dng loi giy c phn loi, trong khi nhng nh my mi thit k s dng hai hoc ba giai on kh mc ch bin giy loi c cht lng thp hn. C s khc bit gia nh thit k Chu u v Bc M. Chu u, cng chng d dng chp nhn cht giy c trng thp v lng m mc trong khi th trng Nht Bn v Bc M th nhy cm hn. Bt ti ch phi c cht lng gn tng ng vi bt nguyn thy. Chu u, my quy gin on nng cao hoc nh bt tang trng c s dng. My phn tn c b tr cui dy chuyn hoc trc giai on kh mc sau nh thit k gn y. Do hn ch trong vic s dng nc, thit b c c hoc lc a c s dng nhiu hn l thit b ra. Nht Bn, cng ngh c trng bao gm thp ngm v thit b nh bt. Cng ngh ny ban u nhm mc ch gim ting n v trnh tiu th in gi cao im. Ko di thi gian bt trong mi trng kim tng kh nng phn tch x si vi nhau v vi tp cht nh mc, plastic. Thit b phn tn c b tr u hoc gia dy chuyn tng lng mc tch khi x si cng nh iu chnh kch thc mc cho ph hp vi tuyn ni.1. Dy chuyn kh mc mt giai on thng thngHnh sau m t c bn dy chuyn ny thng c s dng kh mc cho giy bo. Tuy nhin y l thit k ca 15 nm trc. Ngy nay, phn ln nh my s dng dy chuyn c 2 giai on kh mc.

Giy ti ch c nh r trong quy nng trung bnh 15% - 18%. Sau pha long, sng th loi b tp cht ln nh plastic, giy bn t. Lc ly tm nng cao c s dng loi b ct sn. Sng l v sng khe vn hnh nng 4%. Sau bt c pha long ti nng 1 1,4% cho tuyn ni.Nh th trc nu, gi s c 2% hm lng mc trong bt, cn thit phi loi b 75% lng mc ny bng tuyn ni t trng cn thit cho lm nguyn liu giy bo. Sau tuyn ni bt c th c pha long thm ti nng 0,7% cho giai on lc ly tm (lc nng v lc nh). Giai on sng tinh dng khe c tin hnh sau . Thit b c c c s dng. Bt sau c phn tn, ty trng, v s dng cho my giy.2. Tuyn ni v ra cho sn xut bt nguyn liu cho giy tissueCht n cn c loi b bng phng php ra. C th b tr 2 giai on ra, trc v sau giai on phn tn. Giai on tuyn ni th hai c s dng loi b thm m bn. Thit b DAF c s dng x l nc cng ngh.

3. Dy chuyn kh mc nhiu giai oan cho sn xut nguyn liu cht lng cao cho giy inQu trnh kh mc hai giai on ban u c s tng hiu qu loi sticky. V d, giai on u khng s dng ha cht, nhit thp loi b cc tp cht khng phi mc. Mi trng trung tnh s gim thiu phn r tp cht, nng cao hiu qu tch loi chng bng sng lc. Mt cng ngh khc c giai on hai mi trng axit tnh nhm kt ta sticky v loi b chng bng sng lc.Cng ngh kh mc 2 giai on c s dng rng ri sn xut bt trng cao v khng m mc. Phn tn v ty c tc dng tt n tch mc khi x si do thng c p dng trc giai on kh mc th hai. Ngy nay, tt c cc nh cung cp thit b u ngh dy chuyn kh mc nhiu cp vi nhiu giai on sng, lc ly tm (lc nng, lc nh), tuyn ni, 2 hoc 3 giai on ty trng, 1 hoc 2 giai on phn tn, 2 thit b DAF chuyn x l nc. Tuy nhin, s cn thit ca thit b DAF giai on kh mc u nhiu khi khng r rng. Vn cn nhiu tranh lun trong vn ny. Do chi ph nng lng tng cao, xu hng hin nay l lp t thit b phn tch s trc phn tn ch thc hin phn tn phn on s di c lng m bi tp trung cao hn. sn xut giy LWC, mt giai on nghin ( nghin x si th, di ca TMP) c s dng cui chu trnh v i khi mt giai on ra c s dng kim sot tro.

III. NHNG KH KHN CA CNG NGH KH MC1. Bt khng trngBt thng c mu xm khi mt lng nh mc cn st li. Cc yu t trong cng ngh c th gim kch thc ht mc dn ti chng khng c tch loi hiu qu (v d thi gian nh bt qu lu, nguyn liu giy ti ch cha lng mc nc flexo hoc mc nc jet print).

2. Bt c nhiu vt bnKhi mc kt dnh trn x si v khng c tch loi trong qu trnh kh mc, bt DIP c vt bn. Li ny thng gp khi giy bo c in bng phng php offset thng hoc c gia nhit trn giy khng trng ph. Do phn ng oxi ha cc cht kt dnh mc theo thi gian, cc lin kt ngang bn vng to thnh v mc bm rt cht vi x si. Nin gim in thoi, giy in qung co bng phng php in offset gia nhit trn giy siu cn lng cng thng gy bn bt DIP. 3. Bt c mui khi bt kh mc c mu. Nguyn nhn gy mu l s c mt ca mu ha tan c trong cng thc mc. Phng php trong rotogravure thng cha mu Rhodamine. Mu ny khng chu tc ng ca peroxide hay hydrosulfite. Cc cng thc mc nc cng thng gy mu. 4. m bim bi thng xut hin khi mc khng b phn r nh hn mc mt thng c th phn bit c. Ty thuc vo tng phn. Kch thc ny thng khong 40-60 micron. Nguyn nhn ca m bi l do:- S dng giy ti ch t cc loi tp ch c bng cao mc c lm kh bng tia cc tm.- S dng giy ti ch vn phng (mc in t my photo hoc my in c lm chy v bm cht trn x si).- Giy ti ch c cht lng in cao trn giy c trng ph. 5. StickyKhng c nh ngha chnh xc cho sticky. Sticky c coi l nhng tp cht c tnh dnh, gy hi cho qu trnh sn xut. Nguyn nhn c th l do cc ph gia c s dng trong qu trnh trng ph, in n, gia cng giy. Nha cy cn li trong x si cng gy ra vn sticky, c bit l bt c hc. 6. Mc v cht ph gia thn thin vi mi trngNguyn nhn chnh gy ra vn cho bt DIP l mc in v cc ph gia trong qu trnh gia cng. Cc nghin cu v mc in d tch mc v cc cht keo dnh t gy hi cho qu trnh ti ch ang c pht trin. nhiu lnh vc, s hp tc gia cc nh ti ch v nh cung cp ha cht t kt qu nh cc cht keo dnh s dng trong ng sch c th c tch loi hon ton bi thit b sng. Mc in flexo hoc mc in laser cng s d kh mc hn.

IV. NHNG TIN B TRONG CNG NGH V XU HNG HIN NAY1. Thit b quy btQuy bt nng thp khng cn c s dng do chng phn tn nh cc tp cht. Quy nng trung bnh hoc tang trng c s dng ch yu. Quy nng trung bnh c u im tch mc khi x si tt hn trong khi quy tang trng t lm phn r tp cht hn. Tranh lun v li ch ca 2 thit b vn cn ang din ra. nhng dy chuyn c sn lng cao (600 tn/ngy) quy tang trng c s dng. Dy chuyn c sn lng thp thng s dng thit b quy gin on. Nhiu ci tin hin nay c thit k quy tang trng ngn.2. Thit b sng v lc ly tmNhng nh sn xut c nhiu ci tin t hiu qu trong vic loi b tp cht tt hn. Sng khe tinh contoured vi khe sng nh (0,15 mm thm ch 0,1 mm), lc ly tm thi tp cht nh v.v c s dng hiu qu. Gn y th h sng mi vi thit k rotor c bit c h thng kh flock. Thit b ny c nng sut cao hn cng tc quay rotor, x si qua sng tt hn cng nh tiu hao nng lng thp hn. Cc thit k mi tp trung vo cu hnh khe sng, foil gt cng nh n gin ha giai on sng. 3. Tuyn niThit b tuyn ni ngy nay khc hn vi thit k ban u. Cc nh cung cp ngh thit b c hiu qu tuyn ni cao, mt mt x si thp. Cc ng phun thit k mi, bt c ra ngc chiu gim tht thot bt. Gn y thit b tuyn ni dng ct x l nhiu dng c nghin cu. Nhiu li ch nh chn lc cao, chim t khng gian, d t ng ha, gi thnh u t, vn hnh v bo dng thp.4. Ha hc X phng ca axit bo c s dng rng ri tr tuyn ni . Cc tin b c thc hin lnh vc cht collector tng hp tng thch vi iu kin ha l v nguyn liu phn xng kh mc. Ha cht ny c s dng vi mc dng thp hn so vi x phng. Cht hot ng b mt khng din tch (s dng mt mnh hoc trong nh tng vi x phng) c dng giai on h quy tng kh nng tch mc khi x si. Sau , x phng c b sung trc giai on tuyn ni gom cc ht mc. 5. Kh mc trung tnhNhiu nghin cu c gng pht trin ha cht hot ng trong mi trng trung tnh, gim pht sinh COD. i vi phn ln cc loi giy (hn hp giy bo v tp ch hoc giy vn phng), mi trng trung tnh cho hiu qu kh mc km (ch yu do mc tch khi x si km hn) so vi mi trng kim tnh. Hin nay kh mc trong mi trng kim yu gn trung tnh c quan tm nhiu.6. Cng ngh vi sinhMt vi ci thin trong vic tch mc khi x si bng enzyme c ghi nhn. Trong quy m cng nghip, enzyme c s dng cho giy sn xut t bt ha. Thay th cng ngh kim tnh bng cng ngh trung tnh c enzyme c cho l c tnh kinh t v hiu qu trong vic kh mc v m bn. Ph thuc vo hn hp enzyme c chn, kt qu tch mc v hiu qu tuyn ni t tt. i vi nguyn liu sn xut t bt c, vic s dng enzyme vn cn him v cn nhiu tin b hn na trong kt qu nghin cu cng ngh ny c th c p dng rng ri.7. Qu trnh Cht lng bt DIP c ci thin mt bc ln (tng trng v sch) trong nhng nm gn y. l do dy chuyn DIP s dng nhiu giai on kh mc hn. Vic kt hp nhiu giai on kh mc vi iu kin ha cht v cng ngh khc nhau cho php x l nhiu loi nguyn liu c tnh chuyn bit (v d nh mc flexo). 8. X l nc cng nghDAF c s dng rng ri x l nc cng ngh ca dy chuyn kh mc. Cc ht keo, mc c loi b gim sticky v tng trng. Nhc im ca cng ngh ny l gi thnh ha cht cao c th hot ng hiu qu. Bin php hiu qu loi b cc cht keo v cu t ha tan l c c bt v s dng hiu qu qu trnh ra ngc dng. DAF dng tun hon nc trng my giy hot ng hiu qu hn dy chuyn kh mc. 9. Kim sot qu trnhKim sot trng kh thc hin do trng ca bt DIP pht trin theo mc tch mc nhiu hn mc dng ha cht ty. Tuy nhin mt chng trnh kim sot trng (hoc kim sot hm lng mc) c p dng. H thng ny gim chi ph ha cht ty mt cch hiu qu. Cc tp cht c trong bt nh sticky, giy vn, m bi, tn mc c th c o c bng k thut qut hnh nh. u o m bi v m mc nh online c s dng. V d kim sot qu trnh phn tn nng c th tit kim nng lng v ci thin cht lng bt. Hiu qu phn tn tng ln cng vi nng lng s dng tuy nhin iu ng thi gim trng bt. Thit b o lng m bi c lp t u ra ca thit b phn tn nng cao s ti u ha vic s dng thit b phn tn. Thit b o tn mc online cng c ng dng. Xu hng kim sot qu trnh sng lc c hiu qu trong vic tng cht lng bt v gim thiu dng thi.

V. CHT THI T PHN XNG KH MC 1. Cht thi rnCht thi rn ca phn xng DIP bao gm nhiu dng khc nhau nh sng, lc, c c bt t tuyn ni vi nhiu cng ngh khc nhau (ly tm, li i, vt p), cht thi rn thu gom t thit b DAF v.vTng hm lng cht thi rn ph thuc vo loi nguyn liu (ch yu l hm lng tro), v cng ngh. Tng lng thi ny ti thiu khong 11 - 13% (bao gm 7% - 9% t lng bt tuyn ni) cho sn xut giy in bo. Tuy nhin hm lng ny c th t ti 25% cho sn xut giy in v 50% cho sn xut giy tissue. Vic x l cht thi rn ny kh tn km, mt s nc thm ch cn cm thi. Do nhiu nghin cu c thc hin ti s dng bn t phn xng kh mc nh lm phn bn, n nh t, vt liu xy dng, t, sn xut kh2. Nc thiMc nhim ca nc thi t phn xng DIP ph thuc vo loi nguyn liu ( nhim cao hn i vi bt c), cng ngh kh mc ( nhim cao hn i vi pH cao) v lng nc tiu th (thng thng khong 5 - 15m3). Mt lng ln COD v BOD c chuyn qua my giy cng vi bt. Thng thng qu trnh kh mc to ra 10/50 kg COD v 5/20 kg BOD trn tn bt DIP. Lng nc thi ra ch yu t giai on c c bt mc v mt s lng nc trn khc.Trong trng hp phn xng DIP nh so vi tng th nh my, lng nc thi ny c x l cng vi dng thi ca nh my, tuy nhin lng nc ny thng c x l ha l trc. Dng thi ny cng c th c x l vi sinh trc khi trn vo dng thi ca nh my.

VI. KT LUN Cc tin b trong thy ng lc v ha hc, thit k cc thit b hot ng hiu qu hn, kt hp nhiu cng ngh v khi nim mi trong qu trnh kh mc nng cao hiu qu tch mc v tp cht. T l s dng giy ti ch cho giy in bo tng t 40% nm 1990 ln hn 82%. Mt s loi giy c sn xut t 100% giy ti ch. Cht lng bt ti ch c th t rt cao cho php mc s dng cao trong sn xut giy c bit nh fine paper, SCA, LWC paper for rotogravure

Ti liu ny do Cng ty CP Giy Si Gn tng hp da trn c s cc thng tin tin cy. Tuy nhin chng ti khng m bo v tnh chnh xc, hon chnh ca cc thng tin ti liu ny. Ti liu ny lu hnh rng ri nhm mc ch cung cp thng tin lin quan ti ngnh giy v khng nhm phc v nhu cu ring ca bt k ngi c c th no. Mi sao chp thng tin trong ti liu ny phi trch dn ngun t Cng ty CP Giy Si Gn.