Modern cement production with chalk

1 Coccolithe structure of chalk

2 Principle of the compact kiln system

3 Connection between feed moisture and specific heat consumption [1]

4 Clinker production process for chalk

5 One of the twelve chamber filter presses in Lägerdorf (Ritterhaus&Blecher/Andritz, year of construction 1972)

6 Chalk and marl store

7 Bedeschi reclaimer for chalk

8 Quarrying, transport and preparation/storage of chalk

9 Mobile washing plant at the place of quarrying (Lägerdorf)

10 Dredger (photo design of the feasibility study of IHC)

Classification of the raw material preparation process

Future prospects – the underwater mining method

Summary: Today, hardly any question is raised as regards the winning and preparation of conventional carbonate rock (limestone, marl). Meanwhile there are proven standard methods for the majority of theses widespread cement raw materials, and it is easy to compile a practicable winning and preparation concept based on these methods. Chalk is a very special cement raw material. It is not easy to handle this chalk due to its fineness and moisture. Tailored solutions are in demand. All known processes to make Portland cement clinker from chalk are presented in this article. Problems of winning and preparation are in the focus. From his point of view the author favours a graded modernisation of old factories operating according to the wet process.

1 Chalk as cement raw material

As regards conventional carbonate rock (limestone, marl), problems of quarrying and preparation are only dealt with in passing. Meanwhile there are proven standard methods for the majority of these widespread cement raw materials, and it is easy to compile a practicable quarrying and preparation concept based on these methods. Chalk, however, requires an approach taking into account the peculiarities of this material and of the specific deposit when selecting the process. Many methods and equipment for quarrying, handling and storage, working well in other cases,...