bricks from desert sand

[amor de cosmos]

Researchers make bricks from waste, desert sand
Wagdy Sawahel
9 April 2013 | EN

[CAIRO] Algerian and Malaysian researchers have designed cheap eco-friendly bricks that can be made from waste materials.

Population growth in many urban areas of the developing world is outstripping available housing, prompting interest in making bricks from cheap and durable local materials. Fifty six per cent of the African population is expected to live in urban areas by 2030 (up from 18 per cent in 1950).

Malaysian scientists at the Tenaga National University have produced prototype bricks using waste from the mining, coal and steel industries. They mixed the materials — including quarry dust, the iron oxide that forms on steel during production, and ash from furnaces — with cement and water.

Traditional brick manufacturing uses high pressure or firing in a kiln to shape the bricks. But the scientists formed the bricks within moulds without applying pressure, reducing costs and simplifying the brick-making process, they say.

The researchers add that using waste materials rather than clay or shale conserves resources and maintains the soil quality needed for sustainable agriculture development.

According to the scientists, whose findings are published in the April edition of Construction and Building Materials, the new bricks have a variety of promising properties, including resistance to corrosion and compression.



The bricks could be produced cheaply in the southern region of Algeria, where Saharan sand is especially plentiful and available at minimal cost, according to the study, which was published in December 2012 issue of the Arabian Journal for Science and Engineering. The researchers carried out 750 laboratory tests to hone the bricks.

"If the compression and the thermal resistance of [the bricks] are validated by Algerian building material codes, it could solve the building material crises which Algerian builders are suffering from," Ali Zaidi, a researcher in the Department of Civil Engineering of Algeria's University of Laghouat, tells SciDev.Net.

Zaidi explains that bricks in Algeria are often stressed by the hot summers and cold winters, and assailed by sandstorms.

http://www.scidev.net/en/agriculture...sert-sand.html

[scalziand]

This just seems to be concrete blocks, albeit ones where the (fine)aggregate consists of recycled materials. They still need cement for the binder.... which still has to have been fired some some point anyway.

Not saying that it's a bad idea, just not quite as good as claimed.

[ardecila]

It's a lot more efficient to bring in portland cement and manufacture bricks domestically than it is to import CMUs on palettes.