Effect of particle size on heat of hydration of pozzolan incorporated cements /

Ardoğa, Mehmet Kemal
Hydration reactions, the chemical reactions between cement and water are exothermic. The determination of the heat of hydration and rate of heat evolution of cement are extremely important to understand the hydration mechanism. In this study, clinker and gypsum rock were ground after adding natural pozzolan (trass) with various proportions until a specific fineness value and different cements were obtained. These cements were divided into particle size groups with a sonic sifter and the heat of hydration and rate of heat evolution of each cement group were investigated over a 2-day period. In addition, chemical analyses and particle size distribution analyses were performed with the goal of trying to understand whether there was a connection between cement average particle size, pozzolan content and heat of hydration and the rate of heat evolution periods, or not. It is found that, the addition of a small amount natural pozzolan enhances 2-day heat of hydration of cement due to its nucleation effect. However, in the case where higher amounts of pozzolan are used, the hydration heat decreases because of the dilution effect. Moreover, other possible reasons for the changes in rates of heat evolution of different cement groups are predicted to be the alteration in Ca2+ concentration and dispersion effect. It is shown that fine size groups are more reactive than the coarse size groups during hydration. Using the particle size distributions and chemical analyses of size groups, the behavior of the unsieved cement sample can also be estimated. .


Early heat evolution of different – sized portland cements incorporating ground granulated blast furnace slag
Çetin, Can; Erdoğan, Sinan Turhan; Tokyay, Mustafa; Department of Civil Engineering (2013)
Heat of hydration and rate of heat evolution are two important characteristics of portland cement hydration, significant for various concrete applications such as mass, hot-weather, and cold-weather concreting. The heat of hydration and rate of heat liberation of cement pastes, and concrete made with it, depend heavily on the chemical composition, fineness, and mineral admixture content of the cement used. This thesis investigates the influence of compound composition and GGBFS incorporation in different-si...
Effect of carbonate alkalinity on flotation behavior of quartz
Sayilgan, A; Arol, Ali İhsan (Elsevier BV, 2004-11-19)
Alkalinity is defined as the capacity of a water to neutralize strong acids. In natural waters, this capacity is generally attributable to bases such as HCO3-, CO32 and OH- as well as to species often present in small concentrations such as silicates, borates, ammonia, phosphates and organic bases. Carbonate alkalinity of process waters in mineral processing may change as a result of the seasonal climatic changes, the fresh water source and the amount of recycled process water. Any mineral processing plants...
Early heat evolution in natural pozzolan - incorporated cement hydration
Över, Derya; Tokyay, Mustafa; Erdoğan, Sinan Turhan; Department of Civil Engineering (2012)
Portland cement hydration is an exothermic process. The heat evolved during the hydration process is especially important in mass concrete, and hot and cold weather concreting. Heat of hydration is affected by several factors like chemical composition of cement, fineness of cement and ambient temperature. The major aim of this thesis is to investigate the effect of cement composition and fineness, amount and composition of the fine portion (<45 µm) of natural pozzolan-incorporated cement on hydration heat. ...
Effect of calcium carbonate addition on carbothermic formation of hexagonal boron nitride
ÇAMURLU, HASAN ERDEM; SEVİNÇ, NACİ; Topkaya, Yavuz Ali (Elsevier BV, 2008-01-01)
Effect of CaCO3 on formation of hexagonal boron nitride (h-BN) was investigated by holding CaCO3 free and CaCO3 added activated carbon-boric oxide mixtures under nitrogen atmosphere at 1500 degrees C for 30-120 min. Amount of CaCO3 addition was varied in the range of 0-50 wt.% of the initial mixture. Products were characterized by powder X-ray diffractometry, FT-IR analysis, quantitative chemical analysis, scanning electron microscopy and BET specific surface area analysis. It was observed that calcium carb...
SURUCU, G; Sanin, Faika Dilek (Elsevier BV, 1989-11-01)
This study investigates the effect of aeration basin temperature, pH and dissolved oxygen (DO) concentration on filterability and compressibility characteristics of activated sludge. Laboratory-scale semi-continuous reactors, fed with synthetic wastewater were used. Effects of temperatures of 15, 20, 25, 30, 35°C; pH values of 5.7, 7.2, 8.2, 9.0 and DO concentrations of 0.5, 1.0, 1.5, 2.0, 5.0 ml/l were studied by keeping all the other parameters constant in each case. Results indicated that as the operatin...
Citation Formats
M. K. Ardoğa, “Effect of particle size on heat of hydration of pozzolan incorporated cements /,” M.S. - Master of Science, Middle East Technical University, 2014.