Usimende we-Aluminate, owaziwa nangokuthi usimende we-alumina ephezulu (HAC), uwuhlobo lukasimende olusebenza ngogesi olwenziwa nge-bauxite ne-limestone. Yaqala ukutholwa eFrance ngeminyaka yawo-1900 futhi manje isisetshenziswa kabanzi ekwakheni ngenxa yezakhiwo zayo eziyingqayizivele kanye nezinzuzo ngaphezu kwezinye izinhlobo zikasimende. Kulesi sihloko, sizohlola umsuka, izici, izinzuzo, nokusetshenziswa kukasimende we-aluminate.

Imvelaphi Usimende we-Aluminate watholwa okokuqala eFrance ekuqaleni kwawo-1900 ngunjiniyela waseFrance ogama lakhe linguJules Bied. Wathola ukuthi ngokufudumeza ingxube ye-bauxite ne-limestone ezingeni lokushisa eliphezulu, kukhiqizwa isisetshenziswa esinamandla futhi esihlala isikhathi eside. Le nto ekuqaleni yaziwa ngokuthi i-“ciment fondu” noma “usimende oncibilikisiwe” ngesiFulentshi, futhi kamuva yanikezwa ilungelo lobunikazi njengosimende we-alumina ephezulu.

Izimpawu Usimende we-Aluminate unezici ezimbalwa ezihlukile eziwenza wehluke kwezinye izinhlobo zikasimende. Lezi zici zihlanganisa:

1. Ukusetha okusheshayo: Usimende we-Aluminate usetha ngokushesha, nesikhathi sokumisa cishe amahora angama-4-5. Lokhu kuyenza ifaneleke ezinhlelweni zokusebenza lapho ukulungiselelwa okusheshayo kudingwa khona, njengalapho kubanda noma lapho kudingekile ukulungisa ngokushesha.
2. Amandla okuqala aphezulu: Usimende we-Aluminate unamandla okuqala aphezulu, namandla acindezelayo acishe abe ngu-50-70 MPa ngemva kosuku olulodwa lokwelapha. Lokhu kuyenza ilungele izinhlelo zokusebenza lapho amandla angaphambi kwesikhathi edingeka khona, njengakukhonkolo osakazwa ngaphambili noma ukulungisa.
3. Ukushisa okuphezulu kwe-hydration: Usimende we-Aluminate ukhiqiza ukushisa okuphezulu ngesikhathi senqubo ye-hydration, okungaba kokubili inzuzo kanye nokubi. Lokhu kushisa okuphezulu kwe-hydration kwenza kube kuhle ukusetshenziswa esimweni sezulu esibandayo, njengoba kungasiza ukusheshisa inqubo yokwelapha. Kodwa-ke, kungaholela nasekuqhekekeni nezinye izinhlobo zokulimala uma kungaphathwa kahle.
4. I-Carbon footprint ephansi: Usimende we-Aluminate une-carbon footprint ephansi kunosimende wendabuko wase-Portland, njengoba udinga amazinga okushisa aphansi ngesikhathi sokukhiqiza futhi iqukethe i-clinker encane.

Izinzuzo Usimende we-Aluminate unikeza izinzuzo ezimbalwa ngaphezu kwezinye izinhlobo zikasimende, okuhlanganisa:

1. Ukusetha okusheshayo: I-Aluminate usimende ibeka ngokushesha, engasindisa isikhathi futhi inciphise izindleko zokwakha.
2. Amandla okuqala aphezulu: Usimende we-Aluminate unamandla amakhulu okuqala, anganciphisa isikhathi esidingekayo sokwelapha kanye nokwandisa umkhiqizo.
3. Ukumelana ne-sulfate ephezulu: Usimende we-Aluminate unokumelana okuphezulu nokuhlasela kwe-sulfate, okwenza ifanelekele ukusetshenziswa ezindaweni ezine-sulfate ephezulu, njengezindawo ezisogwini.
4. Ukuncipha okuphansi: Usimende we-Aluminate unezinga eliphansi lokuncipha kunosimende wendabuko wasePortland, onganciphisa ingozi yokuqhekeka nezinye izinhlobo zomonakalo.

Isebenzisa usimende we-Aluminate usetshenziswa ezinhlelweni ezahlukahlukene, kufaka phakathi:

1. Ukhonkolo wokusetha ngokushesha: Usimende we-Aluminate uvame ukusetshenziswa ezinhlelweni lapho ukusetha okusheshayo kudingeka khona, njengalapho kubanda noma ukulungisa ngokushesha.
2. Ukhonkolo osakazwa ngaphambili: Usimende we-Aluminate uvame ukusetshenziswa ekukhiqizeni imikhiqizo kakhonkolo wangaphambili, njengamapayipi kakhonkolo, ama-slabs, namaphaneli.
3. Usimende ohlanjululwayo: Usimende we-Aluminate uvame ukusetshenziswa lapho kukhiqizwa usimende oyinzayo, osetshenziselwa ukuhlanganisa izithando zomlilo ezishisa kakhulu, iziko lomlilo, nezinye izinto ezisetshenziswa ezimbonini.
4. Izicelo ezikhethekile: Usimende we-Aluminate usetshenziswa nasezintweni ezikhethekile, njengasekukhiqizweni kukakhonkolo ozilinganisa kanye nanjenge-binder ezinhlotsheni ezithile zezinto zamazinyo.

Isiphetho Usimende we-Aluminate uwuhlobo oluhlukile lukasimende olunikeza izinzuzo ezimbalwa kunosimende wendabuko wasePortland. Ine-carbon footprint ephansi, isetha ngokushesha, inamandla amakhulu okuqala, futhi imelana kakhulu nokuhlaselwa kwe-sulfate. Usimende we-Aluminate usetshenziswa ezintweni ezehlukene, okuhlanganisa ukhonkolo omiswa ngokushesha, ukhonkolo wangaphambili, usimende ophikisayo, nezinhlelo ezikhethekile ezifana nezinto zamazinyo. Nakuba usimende we-aluminate unezinzuzo eziningi, kubalulekile ukuqaphela ukuthi nawo unezinye izinto ezimbi okufanele zicatshangelwe. Ukushisa okuphezulu kwe-hydration kungaholela ekuqhekekeni nezinye izinhlobo zokulimala uma kungaphathwa kahle, futhi kungase kubize kakhulu kunosimende wendabuko wasePortland. Kodwa-ke, izinzuzo zokusebenzisa usimende we-aluminate zivame ukudlula izindleko, ikakhulukazi ezinhlelweni ezikhethekile lapho izakhiwo zawo ezihlukile zidingeka khona.