Faculty of Chemical Engineering, Kunming University of Science and Technology, Kunming, Yunnan 650500, China; Key Laboratory of Unconventional Metallurgy, Ministry of Education, Kunming, Yunnan 650093, China.
Faculty of Chemical Engineering, Kunming University of Science and Technology, Kunming, Yunnan 650500, China.
J Environ Manage. 2017 Apr 15;191:58-65. doi: 10.1016/j.jenvman.2016.12.048. Epub 2017 Jan 11.
Low-carbon ferrochrome slag (LCFS), a by-product of the ferrochrome alloy industry, has potential for use as a cementitious material due to its pozzolanic characteristic. The objective of the present study was to determine the optimum compound chemical activators for LCFS-based composite cement using an orthogonal test, in which 7 d and 28 d compressive strengths were used as the evaluating indices. The influences of compound chemical activators on the hydration of a composite cement mix were investigated using X-ray diffraction (XRD), scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM/EDS) and thermogravimetry-differential scanning calorimetry (TG-DSC). The optimum activator to activate the composite cement was a compound of NaCl (NC) at a dosage of 0.6%, NaSO (NS) at a dosage of 1.2%, NaF (NF) at a dosage of 0.6% and Al(SO) (AS) at a dosage of 0.9% or 0.7%. The compressive strengths of the optimum composite cement mix at ages of 3, 28 and 180 d increased by 50.1%, 22.4% and 16.5%, respectively. More hydration products including ettringite and calcium silicate hydrate were formed at an early age of hydration. The compound chemical activators effectively activated the ferrochrome slag (FS), blast-furnace slag (BFS) and fly ash (FA) in the composite cement.
低碳铬铁渣（LCFS）是铬铁合金工业的副产品，由于其火山灰特性，具有用作胶凝材料的潜力。本研究的目的是通过正交试验确定基于 LCFS 的复合水泥的最佳复合化学激发剂，其中 7d 和 28d 抗压强度用作评价指标。通过 X 射线衍射（XRD）、扫描电子显微镜结合能谱（SEM/EDS）和热重-差示扫描量热法（TG-DSC）研究了复合化学激发剂对复合水泥浆水化的影响。激活复合水泥的最佳激发剂是 0.6%的 NaCl（NC）、1.2%的 NaSO（NS）、0.6%的 NaF（NF）和 0.9%或 0.7%的 Al(SO)（AS）的复合。在 3、28 和 180d 龄期，最佳复合水泥浆的抗压强度分别提高了 50.1%、22.4%和 16.5%。在水化的早期阶段形成了更多的水化产物，包括钙矾石和硅酸钙水合物。复合化学激发剂有效地激活了复合水泥中的铬铁渣（FS）、高炉矿渣（BFS）和粉煤灰（FA）。
