Iziphumo ze-cellulose ethers ekuguqukeni kwezinto zamanzi kunye nemveliso ye-hydration ye-sulphoaluminate sement paste

Amacandelo amanzi kunye ne-microstructure evolution kwi-cellulose ether eguqulelwe kwi-sulphoaluminate sement (CSA) slurry yaphononongwa yi-low-field nuclear magnetic resonance kunye ne-thermal analyzer. Iziphumo zabonisa ukuba emva kokongezwa kwe-cellulose ether, ibhengeze amanzi phakathi kwezakhiwo ezijikelezayo, ezibonakaliswe njengencopho yesithathu yokuphumla kwixesha elidlulayo lokuphumla (T2) spectrum, kunye nesixa samanzi adsorbed adityaniswa ngokufanelekileyo kunye nedosi. Ukongeza, i-cellulose ether iququzelele kakhulu utshintshiselwano lwamanzi phakathi kwezakhiwo zangaphakathi kunye ne-inter-floc ze-CSA flocs. Nangona ukongezwa kwe-cellulose ether ayinayo impembelelo kwiintlobo zemveliso ye-hydration ye-samente ye-sulphoaluminate, iya kuchaphazela inani lemveliso ye-hydration yobudala obuthile.

Amagama angundoqo:i-cellulose ether; isamente ye-sulfoaluminate; amanzi; iimveliso hydration

0,Intshayelelo

I-cellulose ether, ecutshungulwa kwi-cellulose yendalo ngokusebenzisa uluhlu lweenkqubo, i-admixture yekhemikhali ehlaziyiweyo kunye neluhlaza. I-cellulose ethers eziqhelekileyo ezifana ne-methylcellulose (MC), i-ethylcellulose (HEC), kunye ne-hydroxyethylmethylcellulose (HEMC) isetyenziswa ngokubanzi kumayeza, ukwakhiwa kunye namanye amashishini. Ukuthatha i-HEMC njengomzekelo, inokuphucula kakhulu ukugcinwa kwamanzi kunye nokuhambelana kwe-samente yasePortland, kodwa ukulibazisa ukusetwa kwesamente. Kwinqanaba le-microscopic, i-HEMC nayo inefuthe elibalulekileyo kwi-microstructure kunye nesakhiwo se-pore ye-cement paste. Ngokomzekelo, i-hydration product ettringite (AFt) inokwenzeka ukuba ibe yintonga emfutshane, kwaye i-aspect ratio yayo iphantsi; ngelo xesha, inani elikhulu lee-pores ezivaliweyo zingeniswa kwi-sement paste, ukunciphisa inani lee-pores zokunxibelelana.

Uninzi lwezifundo ezikhoyo kwimpembelelo ye-cellulose ethers kwizinto ezisekelwe kwi-samente zijolise kwi-samente yasePortland. I-Sulfoaluminate Cement (CSA) yisamente enekhabhoni ephantsi ephuhliswe ngokuzimeleyo kwilizwe lam ngenkulungwane yama-20, ene-anhydrous calcium sulphoaluminate njengeyona minerali iphambili. Ngenxa yokuba isixa esikhulu se-AFt sinokuveliswa emva kokufakwa kwamanzi, i-CSA ineenzuzo zamandla okuqala, ukunganyangeki okuphezulu, kunye nokumelana nokugqwala, kwaye isetyenziswa ngokubanzi kwimimandla yekhonkrithi ye-3D yoshicilelo, ukwakhiwa kobunjineli baselwandle, kunye nokulungiswa ngokukhawuleza kwiindawo eziphantsi kweqondo lokushisa. . Kwiminyaka yakutshanje, uLi Jian et al. uhlalutye impembelelo ye-HEMC kumdaka we-CSA ukusuka kwiimbono zamandla oxinzelelo kunye nobuninzi obumanzi; Wu Kai et al. wafunda umphumo we-HEMC kwinkqubo yokuqala ye-hydration ye-samente ye-CSA, kodwa amanzi kwi-samente ye-CSA elungisiweyo Umthetho wokuziphendukela kwezixhobo kunye nokubunjwa kwe-slurry awaziwa. Ngokusekelwe koku, lo msebenzi ugxile ekusasazweni kwexesha lokuphumla elinqamlezayo (T2) kwi-CSA slurry yesamente ngaphambi nangemva kokongeza i-HEMC ngokusebenzisa isixhobo esisezantsi se-nuclear magnetic resonance, kwaye sihlalutya ngakumbi ukufuduka kunye nokutshintsha umthetho wamanzi emanzini. uludaka. Ukutshintshwa kokwakheka kwe-samente intlama yaphononongwa.

1. Linge

1.1 Iimathiriyeli ekrwada

Iisamente ezimbini ze-sulphoaluminate ezifumanekayo kurhwebo zisetyenzisiwe, ezichazwe njenge-CSA1 kunye ne-CSA2, kunye nelahleko ekutshisweni (LOI) engaphantsi kwe-0.5% (iqhezu lobuninzi).

Kusetyenziswa ii-hydroxyethyl methylcellulose ezintathu ezahlukeneyo, ezichazwe njenge-MC1, MC2 kunye ne-MC3 ngokulandelelanayo. I-MC3 ifunyenwe ngokuxuba i-5% (iqhezu lobuninzi) i-polyacrylamide (PAM) kwi-MC2.

1.2 Umlinganiselo wokuxuba

Iintlobo ezintathu ze-cellulose ethers zaxutywa kwisamente ye-sulphoaluminate ngokulandelanayo, iidosi ziyi-0.1%, 0.2% kunye ne-0.3% (iqhezu lobuninzi, elifanayo ngezantsi). Umlinganiselo oqingqiweyo wamanzi-samente ngu-0.6, kwaye umlinganiselo we-samente wamanzi we-samente yamanzi unomsebenzi omhle kwaye akukho gazi ngokuvavanywa kokusetyenziswa kwamanzi okuhambelana nomgangatho.

1.3 Indlela

Isixhobo se-NMR esisezantsi esisetyenziswe kuvavanyo yiPQ⁃001 NMR analyzer evela Shanghai Numei Analytical Instrument Co., Ltd. Amandla kazibuthe umazibuthe osisigxina yi 0.49T, i-proton resonance frequency yi-21MHz, kwaye ubushushu bemagnethi bugcinwa rhoqo kwi-32.0°C. Ngethuba lovavanyo, ibhotile yeglasi encinci equkethe isampuli ye-cylindrical yafakwa kwi-coil ye-probe yesixhobo, kwaye ukulandelelana kwe-CPMG kusetyenziswe ukuqokelela umqondiso wokuphumla we-cement paste. Emva kokuguqulwa kwesoftware yohlalutyo lokulungelelanisa, i-T2 inversion curve yafunyanwa ngokusebenzisa i-algorithm ye-Sirt inversion. Amanzi anamanqanaba ahlukeneyo enkululeko kwi-slurry aya kubonakaliswa ziincopho ezahlukeneyo zokuphumla kwi-spectrum yokuphumla, kwaye indawo yencopho yokuphumla inxibelelene kakuhle nobungakanani bamanzi, ngokusekwe phezu kohlobo kunye nomxholo wamanzi eludaka. inokuhlalutywa. Ukuze kuveliswe iresonance yemagnethi yenyukliya, kuyimfuneko ukuqinisekisa ukuba i-o1 (iyunithi: kHz) yefrikhwensi kanomathotholo iyangqinelana nobuninzi bemagnethi, kwaye i-O1 ilinganiswa yonke imihla ngexesha lovavanyo.

Iisampulu zahlalutywa yi-TG?DSC kunye ne-STA 449C edityanisiweyo yomhlalutyi we-thermal evela kwi-NETZSCH, eJamani. I-N2 isetyenziswe njengendawo yokukhusela, izinga lokushisa laliyi-10°C / min, kunye neqondo lokushisa lokuskena laliyi-30-800°C.

2. Iziphumo kunye nengxoxo

2.1 Ukuvela kwezinto zamanzi

2.1.1 I-ether yeselulosi engakhutshwanga

Iincopho ezimbini zokuphumla (ezichazwe njengeencopho zokuqala kunye neyesibini zokuphumla) zinokubonwa ngokucacileyo kwixesha lokuphumla elinqamlezayo (T2) imbonakalo ye-slurries yesamente ye-sulphoaluminate emibini. Incopho yokuqala yokuphumla ivela ngaphakathi kwesakhiwo se-flocculation, esineqondo eliphantsi lenkululeko kunye nexesha elifutshane elinqamlezayo lokuphumla; Incopho yesibini yokuphumla isuka phakathi kwezakhiwo ezijikelezayo, ezinomlinganiselo omkhulu wenkululeko kunye nexesha elide lokuphumla elinqamlezayo. Ngokwahlukileyo koko, i-T2 ehambelana nencopho yokuqala yokuphumla yeesamente ezimbini iyathelekiseka, ngelixa incopho yesibini yokuphumla yeCSA1 ibonakala kamva. Ngokwahlukileyo kwiklinka yesamente yesulphoaluminate kunye nesamente eyenziwe ngokwayo, iincopho ezimbini zokuphumla ze-CSA1 kunye ne-CSA2 ngokuyinxenye ziyadibana ukusuka kwimeko yokuqala. Ngenkqubela phambili ye-hydration, incopho yokuqala yokuphumla ngokuthe ngcembe ithande ukuzimela, indawo iyancipha ngokuthe ngcembe, kwaye iyanyamalala ngokupheleleyo malunga nemizuzu engama-90. Oku kubonisa ukuba kukho iqondo elithile lotshintshiselwano lwamanzi phakathi kwesakhiwo se-flocculation kunye nesakhiwo se-flocculation yee-pastes ezimbini zesamente.

Utshintsho lwendawo encopho yencopho yesibini yokuphumla kunye nokutshintsha kwexabiso le-T2 elihambelana nencopho yencopho ngokulandelelana kubonakalisa utshintsho lwamanzi asimahla kunye nomxholo wamanzi obopheleleke ngokwasemzimbeni kunye notshintsho lwenqanaba lenkululeko yamanzi kwi-slurry. . Ukudityaniswa kwezi zimbini kunokubonisa ngokubanzi ngakumbi Inkqubo ye-hydration ye-slurry. Ngenkqubela phambili ye-hydration, indawo ephakamileyo iyancipha ngokuthe ngcembe, kwaye ukutshintshwa kwexabiso le-T2 ukuya ngakwesobunxele kwandisa ngokuthe ngcembe, kwaye kukho ubudlelwane obuhambelanayo phakathi kwabo.

2.1.2 Kufakwe i-cellulose ether

Ukuthatha i-CSA2 exutywe ne-0.3% MC2 njengomzekelo, i-spectrum yokuphumla ye-T2 ye-samente ye-sulphoaluminate emva kokongeza i-cellulose ether ingabonwa. Emva kokongeza i-cellulose ether, incopho yesithathu yokuphumla emele ukufakwa kwamanzi nge-cellulose ether yabonakala kwindawo apho ixesha lokuphumla elinqamlezayo lalilikhulu kune-100ms, kwaye indawo yencopho yanda ngokuthe ngcembe ngokunyuka komxholo we-cellulose ether.

Ubungakanani bamanzi phakathi kwezakhiwo ze-flocculation zichaphazelekayo ngokufuduka kwamanzi ngaphakathi kwesakhiwo se-flocculation kunye ne-adsorption yamanzi ye-cellulose ether. Ngoko ke, ubungakanani bamanzi phakathi kwezakhiwo ze-flocculation zihambelana nesakhiwo se-pore yangaphakathi ye-slurry kunye nomthamo we-adsorption wamanzi we-cellulose ether. Ummandla we-relaxation peak yesibini iyahluka kunye Umxholo we-cellulose ether uyahluka kunye neentlobo ezahlukeneyo zesamente. Ummandla wencopho yesibini yokuphumla ye-CSA1 slurry yehla ngokuqhubekayo ngokunyuka komxholo we-cellulose ether, kwaye yayiyeyona incinci kumxholo we-0.3%. Ngokwahlukileyo, indawo yesibini yokuphumla yokuphumla ye-CSA2 slurry iyanda ngokuqhubekayo ngokunyuka komxholo we-cellulose ether.

Dwelisa utshintsho lwendawo yencopho yesithathu yokuphumla ngokunyuka komxholo we-cellulose ether. Ekubeni indawo ephezulu ichaphazeleka ngumgangatho wesampuli, kunzima ukuqinisekisa ukuba umgangatho wesampulu eyongezelelweyo ufana xa ulayisha isampuli. Ke ngoko, umlinganiselo wendawo usetyenziselwa ukubonakalisa isixa somqondiso wencopho yesithathu yokuphumla kwiisampuli ezahlukeneyo. Ukusuka kutshintsho lommandla wencopho yesithathu yokuphumla kunye nokunyuka komxholo we-cellulose ether, kunokubonwa ukuba ngokunyuka komxholo we-cellulose ether, indawo yencopho yesithathu yokuphumla ibonise ngokusisiseko ukunyuka (kwi- I-CSA1, xa umxholo we-MC1 wawuyi-0.3%, yayingaphezulu Indawo ye-relaxation peak yesithathu iyancipha kancinane kwi-0.2%), ebonisa ukuba ngokunyuka komxholo we-cellulose ether, amanzi adsorbed nawo ayanda ngokuthe ngcembe. Phakathi kodaka lwe-CSA1, i-MC1 yayinokufunxwa ngcono kwamanzi kune-MC2 kunye ne-MC3; ngelixa phakathi kwe-CSA2 slurries, i-MC2 yayineyona nto ingcono yokufunxa amanzi.

Inokubonwa ukusuka kutshintsho lommandla wencopho yesithathu yokuphumla kwiyunithi yobunzima be-CSA2 kunye nexesha kumxholo we-0.3% ye-cellulose ether ukuba indawo yencopho yesithathu yokuphumla kwiyunithi nganye iyancipha ngokuqhubekayo kunye nokuhanjiswa, ebonisa ukuba Ekubeni izinga lokugalela kwe-CSA2 likhawuleza kakhulu kunelo le-clinker kunye ne-samente eyenziwe ngokwayo, i-ether ye-cellulose ayinaxesha lokunyuka kwamanzi angaphezulu, kwaye ikhupha amanzi adsorbed ngenxa yokwanda ngokukhawuleza koxinzelelo lwesigaba solwelo kwi-slurry. Ukongeza, i-adsorption yamanzi ye-MC2 yomelele kune-MC1 kunye ne-MC3, ehambelana nezigqibo zangaphambili. Inokubonwa kutshintsho lwendawo encopho yobunzima beyunithi nganye yencopho yesithathu yokuphumla ye-CSA1 kunye nexesha kwiidosi ezahlukeneyo ze-0.3% ze-cellulose ethers ukuba umgaqo wokutshintsha wencopho yesithathu yokuphumla ye-CSA1 yahlukile kuleyo ye-CSA2, kwaye indawo ye-CSA1 inyuka ngokufutshane kwisigaba sokuqala sokuhamba kwamanzi. Emva kokunyuka ngokukhawuleza, yehla ukunyamalala, okunokuthi kungenxa yexesha elide lokujika kwe-CSA1. Ukongeza, i-CSA2 iqulethe i-gypsum eninzi, i-hydration ilula ukwenza ngakumbi i-AFt (3CaO Al2O3 3CaSO4 32H2O), idla amanzi amaninzi asimahla, kwaye izinga lokusetyenziswa kwamanzi lidlula izinga lokungeniswa kwamanzi nge-cellulose ether, enokukhokelela kwi-Ether. Ummandla wencopho yesithathu yokuphumla ye-CSA2 slurry iqhubekile ukuhla.

Emva kokufakwa kwe-cellulose ether, incopho yokuqala neyesibini yokuphumla nayo yatshintsha kwinqanaba elithile. Inokubonwa ukusuka kwincopho yobubanzi bencopho yesibini yokuphumla kweentlobo ezimbini zodaka lwesamente kunye nodaka olutsha emva kokongeza i-ether ye-cellulose ukuba ububanzi bencopho yesibini yokuphumla kwe-slurry entsha yahlukile emva kokongeza i-ether cellulose. ukwanda, ubume bencopho buthanda ukusasazeka. Oku kubonisa ukuba ukufakwa kwe-ether cellulose kuthintela i-agglomeration yamasuntswana esamente ukuya kumlinganiselo othile, yenza ukuba ulwakhiwo lwe-flocculation lube lula, ludodobalise iqondo lokubophelela kwamanzi, kwaye kwandisa iqondo lenkululeko yamanzi phakathi kwezakhiwo ze-flocculation. Nangona kunjalo, ngokunyuka kwedosi, ukwanda kobubanzi bencopho akubonakali, kwaye ububanzi bencopho kwezinye iisampuli buyancipha. Kungenzeka ukuba ukonyuka kwedosi kwandisa i-viscosity yesigaba solwelo lwe-slurry, kwaye kwangaxeshanye, i-adsorption ye-cellulose ether kumasuntswana e-samente iphuculwe ukuze ibangele i-flocculation. Iqondo lenkululeko yomswakama phakathi kwezakhiwo liyancitshiswa.

Isigqibo sinokusetyenziselwa ukuchaza inqanaba lokwahlula phakathi kwencopho yokuqala neyesibini yokuphumla. Iqondo lokuhlukana lingabalwa ngokweqondo lesisombululo = (icandelo lokuqala-Asaddle)/icandelo le-Afirst, apho i-Afirst component kunye ne-Asaddle imele ubuninzi be-amplitude ye-peak yokuqala yokuphumla kunye ne-amplitude yeyona ndawo iphantsi phakathi kweencopho ezimbini, ngokulandelelanayo. Iqondo lokwahlula lingasetyenziselwa ukubonakalisa iqondo lokutshintshiselana kwamanzi phakathi kwesakhiwo se-slurry flocculation kunye nesakhiwo se-flocculation, kwaye ixabiso ngokubanzi ngu-0-1. Ixabiso eliphezulu lokwahlula libonisa ukuba iinxalenye ezimbini zamanzi zinzima kakhulu ukutshintshiselana, kwaye ixabiso elilingana ne-1 libonisa ukuba iindawo ezimbini zamanzi azikwazi ukutshintshiselana nonke.

Inokubonwa kwiziphumo zokubala zedigri yokwahlula ukuba idigri yokuhlukana kweesamente ezimbini ngaphandle kokufaka i-cellulose ether ilingana, zombini malunga ne-0.64, kwaye idigri yokwahlukana iyancipha kakhulu emva kokongeza i-cellulose ether. Kwelinye icala, isisombululo siyancipha ngakumbi ngokunyuka kwedosi, kwaye isisombululo sezincopho zimbini zide zehle ziye ku-0 kwi-CSA2 exutywe ne-0.3% MC3, ebonisa ukuba i-cellulose ether ikhuthaza kakhulu ukutshintshiselana kwamanzi ngaphakathi naphakathi. Izakhiwo zeflocculation . Ngokusekelwe kwinto yokuba ukufakwa kwe-ether ye-cellulose ayinayo impembelelo kwisithuba kunye nommandla wencopho yokuqala yokuphumla, kunokucingelwa ukuba ukuhla kwesisombululo kubangelwa kukwanda kobubanzi bencopho yesibini yokuphumla, kwaye Isakhiwo se-flocculation esikhululekile senza ukuba utshintshiselwano lwamanzi phakathi kwangaphakathi nangaphandle lube lula. Ukongezelela, ukugqithwa kwe-cellulose ether kwisakhiwo se-slurry kuphucula ngakumbi iqondo lokutshintshiselana kwamanzi phakathi kwangaphakathi nangaphandle kwesakhiwo se-flocculation. Kwelinye icala, isiphumo sokunciphisa isisombululo se-cellulose ether kwi-CSA2 yomelele kune-CSA1, enokuthi ibe ngenxa yendawo encinci yomphezulu kunye nobungakanani besuntswana elikhulu le-CSA2, elinovakalelo ngakumbi kwisiphumo sokusasazeka kwe-ether ye-cellulose emva kokunciphisa i-cellulose ether. ukufakwa.

2.2 Utshintsho ekubunjweni kodaka

Ukusuka kwi-spectra ye-TG-DTG ye-CSA1 kunye ne-CSA2 i-slurries i-hydrated i-90 min, i-150 min kunye ne-1 imini, kunokubonwa ukuba iintlobo zeemveliso ze-hydration azizange zitshintshe ngaphambi nangemva kokongeza i-cellulose ether, kunye ne-AFt, i-AFm kunye ne-AH3 yonke. yenziwe. Uncwadi lubonisa ukuba uluhlu lokubola lwe-AFt luyi-50-120°C; uluhlu lokubola lwe-AFm yi-160-220°C; uluhlu lokubola lwe-AH3 luyi-220-300°C. Ngenkqubela phambili ye-hydration, ilahleko yobunzima besampulu yanda ngokuthe ngcembe, kwaye iimpawu ze-DTG eziphakamileyo ze-AFt, AFm kunye ne-AH3 ngokuthe ngcembe zacaca, zibonisa ukuba ukubunjwa kweemveliso ezintathu ze-hydration zanda ngokuthe ngcembe.

Ukusuka kwiqhezu lobunzima bemveliso nganye ye-hydration kwisampulu kwiminyaka eyahlukeneyo ye-hydration, kunokubonwa ukuba isizukulwana se-AFt sesampuli esingenanto kwi-1d yobudala sidlula isampuli exutywe ne-cellulose ether, ebonisa ukuba i-cellulose ether inempembelelo enkulu ukumanzisa koludaka emva kokujija. Kukho umphumo wokulibaziseka okuthile. Ngemizuzu ye-90, ukuveliswa kwe-AFm kweesampuli ezintathu zahlala zifana; kwimizuzu ye-90-150, ukuveliswa kwe-AFm kwisampuli engenanto yayicotha kakhulu kuneyamanye amaqela amabini eesampuli; emva kosuku olu-1, umxholo we-AFm kwisampulu engenanto yayifana naleyo yesampuli exutywe ne-MC1, kwaye umxholo we-AFm wesampulu ye-MC2 wawuphantsi kakhulu kwezinye iisampuli. Ngokubhekiselele kwimveliso ye-hydration AH3, isantya sokuvelisa isampula engenanto ye-CSA1 emva kokufakwa kwamanzi kwimizuzu engama-90 yayicotha kakhulu kune-ether ye-cellulose, kodwa izinga lokuvelisa lalikhawuleza kakhulu emva kwemizuzu engama-90, kunye ne-AH3 yokuvelisa iisampulu ezintathu. yayilingana ngosuku olu-1.

Emva kokuba i-slurry ye-CSA2 ifakwe i-hydrated ye-90min kunye ne-150min, isixa se-AFT esiveliswe kwisampuli exutywe ne-cellulose ether yayingaphantsi kakhulu kwesampulu engenanto, ebonisa ukuba i-cellulose ether nayo ibe nefuthe elithile lokunciphisa i-CSA2 slurry. Kwiisampuli kwi-1d yobudala, kwafunyaniswa ukuba umxholo we-AFt wesampulu engenanto wawusephezulu kunesampulu exutywe ne-cellulose ether, ebonisa ukuba i-cellulose ether isenomphumo othile wokunciphisa i-hydration ye-CSA2 emva kokumiswa kokugqibela, kunye neqondo lokubuyiswa kwe-MC2 lalilikhulu kunesampulu eyongezwe nge-cellulose ether. MC1. Ngemizuzu engama-90, inani le-AH3 eliveliswe yisampuli engenanto yayingaphantsi kancinci kunesampulu exutywe ne-cellulose ether; kwimizuzu ye-150, i-AH3 eveliswe yisampuli engenanto igqithise isampuli exutywe ne-cellulose ether; ngosuku lwe-1, i-AH3 eveliswe yiisampulu ezintathu yayilingana.

3. Isiphelo

(1) I-ether ye-cellulose inokukhuthaza kakhulu ukutshintshiselana kwamanzi phakathi kwesakhiwo se-flocculation kunye nesakhiwo se-flocculation. Emva kokufakwa kwe-cellulose ether, i-ether ye-cellulose ibhengeza amanzi eludaka, oluphawulwa njengencopho yesithathu yokuphumla kwi-spectrum yexesha lokuphumla elinqamlezileyo (T2). Ngokunyuka komxholo we-cellulose ether, ukuxutywa kwamanzi kwe-cellulose ether kwanda, kwaye indawo yokuphumla okwesithathu inyuka. Amanzi afunxwa yi-cellulose ether akhululwa ngokuthe ngcembe kwisakhiwo se-flocculation kunye ne-hydration ye-slurry.

(2) Ukufakwa kwe-ether ye-cellulose kuthintela i-agglomeration ye-cement particles ukuya kwinqanaba elithile, okwenza ulwakhiwo lwe-flocculation lube lula; kunye nokunyuka komxholo, i-viscosity yesigaba se-liquid ye-slurry iyanda, kwaye i-ether ye-cellulose inefuthe elikhulu kwiincinci ze-samente. Isiphumo sobhengezo esongeziweyo sinciphisa iqondo lenkululeko yamanzi phakathi kwezakhiwo ezidadayo.

(3) Ngaphambi nangemva kokongezwa kwe-cellulose ether, iintlobo zeemveliso ze-hydration kwi-sulphoaluminate sement slurry azizange zitshintshe, kunye ne-AFt, AFm kunye ne-aluminium glue; kodwa i-cellulose ether ilibazisekile kancinane ukusekwa kweemveliso ze-hydration effect.