The comparison of the effect of Zinc compounds on hydration of ordinary Portland cement

conference paper

English

The content of heavy metals in various secondary industrial products and alternative fuels increases with the ecological push for reuse of waste materials and recycling. This effect is especially visible in the Portland cement properties. The cement production often involves burning of old tires as fuel and source of iron oxide and ground communal waste or industrial waste sludge as cheap fuel. The burning of waste in rotary kiln introduces heavy metal into cement clinker that have adverse effects on the properties and use of cement. Zinc has been proven to drastically increase of induction period of cement setting. The negative effect of zinc compounds on hydration of ordinary Portland cement was measured by isoperibolic calorimetry. Zinc was added to the cement in the form of two soluble salts of Zn(NO3)2 hydrate, ZnCl2 and a poor soluble compound ZnO. The concentration of zinc added was chosen as 0.1, 0.5 and 1 mass %. The results show significant retardation of cement hydration with increasing zinc content with ZnO causing most drastic increase in induction period

Portland cement, Hydration, Zinc, Heavy metals, isoperibolic calorimetry

MATĚJKA, L.; ŠILER, P.; NOVOTNÝ, R.; ŠVEC, J.; MÁSILKO, J.

21. 11. 2019

Vysoké učení technické v Brně, Fakulta chemická, Purkyňova 464/188 612 00 Brno

Brno

978-80-214-5808-6

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