Hydration of calcium sulfoaluminate cement in the system of paste and suspension : master thesis

Kalcij sulfoaluminatni cement (CSA), je alternativa portland cementu (OPC). Tehnologija proizvodnje CSA karakterizirana je manjom emisijom ugljikovog dioksida, nižim temperaturama proizvodnje te mogućnošću korištenja otpadnog materijala kao sirovine. CSA u odnosu na OPC, razvija veće rane čvrstoće, brže očvršćava i posjeduje bolja antikorozivna svojstva. U ovom radu istraživana su hidratacijska svojstva tržišno dostupnog cementa Ali Pre Green (Italcementi, Heidelberg Cement Group). Hidratacija cementa je provedena u sustavu cementnih pasta s vodocementnim omjerom (v/c = 0,31 i 0,5) i suspenzija (v/c = 4). Hidratacijom nastale faze određene su termogravimetrijom (TG / DTG-DTA) i difrakcijom X-zraka na prahu (XRD). Istraživanje sustava cementnih suspenzija i pasta ukazuje na vrlo visoku hidratacijsku aktivnost do 48 sati u sustavima pasta i do 24 sata u vodenim suspenzijama. Ukupna oslobođena toplina hidratacije usporediva je s vrijednostima za OPC, dok je glavni produkt hidratacije u vodenim suspenzijama etringit.Calcium sulfoaluminate cement (CSA) is a sustainable alternative to Ordinary Portland Cement (OPC). The producing technology of CSA is characterised by lower carbon dioxide emission, lower temperature for producing clinker and the possibility to reuse waste materials as raw materials in the production process. CSA has an advantage compared to the OPC, such as higher early strength, faster hardening, and better anti-corrosion properties. In this paper, research is focused on the hydration on the market commercially available Ali Pre Green as CSA cement (Italcementi, Heidelberg Cement Group). Hydration of cement was carried out in a system of cement pastes with a ratio of water/cement = 0.31 (w/c) and suspension (w/c = 4). The content of the hydration product was determined by thermal methods (TG / DTG-DTA), X-ray diffraction (XRD). Research on cement paste and suspension systems indicates very high hydration activity of up to 48 hours in paste systems and up to 24 hours in aqueous suspensions. The total heat of hydration released is comparable to the values for OPC until the main product of hydration in the system of water suspension is Ettringite