Publication detail

Long-term Observation of Yeelimite Clinker Hydration in Environment of Saturated Water Vapour

MOKRÁ, J. KULÍSEK, K. GAZDIČ, D. FRIDRICHOVÁ, M.

Original Title

Long-term Observation of Yeelimite Clinker Hydration in Environment of Saturated Water Vapour

Type

conference paper

Language

English

Original Abstract

Due to ecological overloading decrease, industrial by-products are utilized. Fly ash also belongs among these by-products. In Portland-composite cements, the high-temperature fly ash is applied nowadays, but fluidized bed combustion fly ash (FBC fly ash) is not used. The reason is that the FBC fly ash hydrates to form an undesirable ettringite, C3A.3CaSO4.32H2O. Decomposition temperature of ettringite in ambient conditions is most often mentioned in a range of 50 °C to 110 °C. In order to assess the ettringite long-term stability, ettringite was synthesized by hydration of mineral yeelimite, 3CaO.3Al2O3.CaSO4. The aim of this paper is long-term observation of the hydration of yeelimite in environment of saturated water vapour and examination of how stable the products of hydration are under given conditions. Raw materials for preparation of yeelimite were gypsum, limestone and corundum, weighed according to stoichiometric ratio of yeelimite. The mixture was heated at temperature of 1200 °C, soak 3 hours. After quenching and grinding, yeelimite was hydrated with a water-yeelimite ratio of 0.3. The system was cured as pastes and stored in conditions at laboratory temperature and in settings of saturated water vapour (100% R.H.). In order to follow the progress of synthesis regularly, namely up to age of 180 days of hydration, X-ray diffraction (XRD) was chosen using diffractometer Empyrean PANalytical (CuK-alpha). Based on the XRD patterns, only minor part of ettringite was formed, whilst a majority of yeelimite was preserved. It has been found that ettringite was not the only one product of yeelimite hydration. From an age of 20 days of hydration, a small amount of monosulfate was identified, whose quantity rose gradually. Especially at later ages of hydration, transformation of ettringite into monosulfate was observed.

Keywords

Yeeilimite; ettringite; monosulfate; saturated water vapour; bed combustion fly ash

Authors

MOKRÁ, J.; KULÍSEK, K.; GAZDIČ, D.; FRIDRICHOVÁ, M.

Released

3. 8. 2016

Publisher

Elsevier

Location

Černá Hora

ISBN

978-1-5108-2855-1

Book

Ecology and new building materials and products 2016

ISBN

1877-7058

Periodical

Procedia Engineering

Year of study

151

Number

1

State

Kingdom of the Netherlands

Pages from

94

Pages to

99

Pages count

6

URL

Full text in the Digital Library

BibTex

@inproceedings{BUT127929,
  author="Jana {Pekárková} and Karel {Kulísek} and Dominik {Gazdič} and Marcela {Fridrichová}",
  title="Long-term Observation of Yeelimite Clinker Hydration in Environment of Saturated Water Vapour",
  booktitle="Ecology and new building materials and products 2016",
  year="2016",
  journal="Procedia Engineering",
  volume="151",
  number="1",
  pages="94--99",
  publisher="Elsevier",
  address="Černá Hora",
  doi="10.1016/j.proeng.2016.07.385",
  isbn="978-1-5108-2855-1",
  issn="1877-7058",
  url="https://www.sciencedirect.com/science/article/pii/S1877705816317738"
}