From marlstone to rotary kilns – the early development of Portland cements in Central Europe

Author(s): Farkas Pintér, Christophe Gosselin, Thomas Köberle, István Vidovszky, Johannes Weber
Paper category: Proceedings
Book title: Proceedings of the 5th Historic Mortars Conference
Editor(s): José Ignacio Álvarez, José María Fernández, Íńigo Navarro, Adrián Durán, Rafael Sirera
ISBN: 978-2-35158-221-3
e-ISBN: 978-2-35158-222-0
Publisher: RILEM Publications SARL
Publication year: 2019
Pages: 819-832
Total Pages: 14
Language : English

Abstract: Based on the optical and electron microscopic investigations of Portland cement structures from nine Central European historic objects built between the 1860s and 1908, the present paper discusses the phase composition, microstructural properties of unhydrated residues and hydrated cement phases as well as fingerprints of the main milestones of the development of early Portland cement production. The early cements of the 1860s were characterized by their coarse grain size and very heterogeneous composition containing, besides C3S, C2S, C3A and ferrite, a wide range of under and over burned components. Although the Portland cements produced in the following decades were less heterogeneous, cement phases suggest the absence of accurate control of the raw mix and the use of different types of shaft kilns and ring kilns. Finally, Portland cements produced in the early 1900s show features characteristic of clinker burned in early rotary kilns. Despite the slight increase in cement fineness, analyses suggest that the evolution of milling technique could not keep up with the calcination technologies. The compositional differences of hydration products between the samples produced in different periods were mostly due to the addition of calcium sulfate which presumably started in the last decades of the 19th century.

Online publication : 2019
Publication type : full_text
Public price (Euros) : 0.00