Micro Concrete tiles, mud bricks, pozzolanic cement: EcoSur - Home

A group from EcoSouth recently had an opportunity to visit the Ceramic Museum in Switzerland . Historically, bricks and tiles made of burnt clay have been among the principal construction materials in Europe throughout the centuries, and the colleagues were interested in learning about pre-industrial brick production.

The museum has an impressive collection of product samples from Roman times to the present, and is directed by an archeologist who combines her scientific knowledge with what she has learned in the practice. She enthusiastically related the struggle to preserve some vestiges of this art, as today large scale automatic production has completely displaced artesanal production, and even the mechanics of production.

We saw decorated bricks from the Middle Ages, fabricated by monks, to build columns with relieves. Some of these bricks stand out because of their enormous size and weight, almost 100kg. To know how to dry and burn them without their cracking in the process is a highly developed art.

During the entire morning we had lively interchanges, in which we could compare different levels of technology over time. Most outstanding for us was not only that we understood what we saw, but also that we could contribute our knowledge, as in many southern countries the production methods continue to be the same, while in post-industrial countries they are considered historic. In order to understand this, one has to know that ceramic technology has not changed significantly throughout many centuries, and that the preparation of the clay and the process of molding has undergone little change. For the burning process various types of ovens are used, and today almost all known varieties are used, including open-air burning in some African countries.

It has been little more than a hundred years since brick factories began to use mechanical systems for the preparation of the clay and extrusion for molding. In Europe Hoffmann ovens began to dominate and in India the so-called “Bull Trench Kiln”.

We concluded this fascinating visit in a recently restored brick factory, where the association that maintains the museum organizes courses for those interested in learning how bricks were made anciently. The two-story wooden building has semi-open walls in order to let the air circulate to dry the products. In the lower story bricks are made and in the upper roof tiles are produced. The kiln has been built with thick brick walls and is integrated into the building itself. It was interesting to learn that the owner himself had a horse and wagon to deliver the products.

The interchange was extremely enriching, as much for the museum director as for us, as we all have had some technical and practical experience with the theme, especially Martin Melendez who has experimented with different kilns and burning methods, and Fernando Martirena who currently is developing methods to reduce the burning time.