Can Egypt build with desert sand? Egypt’s construction sector is under pressure to slash its carbon emissions, and the country’s abundance of desert sand could be the key to greenify the sector that contributes a substantial part of the country’s GDP, according to a research paper by Future University in Egypt’s Assistant Professor of Architectural Engineering Dina Khater. The paper explores how the country’s desert sand supply could replace carbon-intensive building staples like Portland cement and clay bricks, assessing its potential as a green building material.

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The building materials sector is one of Egypt’s biggest carbon emitters. Cement production alone accounts for around 14% of the country’s CO2 emissions, which is twice the global average. Much of this is driven by energy-intensive processes and heavy reliance on coal and petcoke, both of which are heavy carbon emitters.

Why it matters? “Nearly 96% of Egypt is undeveloped desert territory, and rapid population growth has made metropolitan centers denser. This highlights the need for prioritizing sand as a locally accessible sustainable resource for future urban development,” the paper argues.

Why sand? Sand is among the most available materials in Egypt, with deserts making up most of the country’s land, according to the paper, and is among the most underutilized resources. Specific types of Egyptian desert sand, especially quartz (also known as silica sand) and feldspar sand, could be used in construction once stabilized or compacted.

One method is bio-cementation, which could offer a greener way to stabilize weak ground. Researchers are exploring how to use natural processes to strengthen sandy soils by accelerating the formation of calcite, which is the mineral that cements sand into sandstone over time, according to a study by Professor Michael Long at University College Dublin’s School of Civil Engineering. Injecting bacteria or enzymes into sand that contains calcite triggers a reaction that produces calcium carbonate, which binds the grains together. This process could create stronger, more stable ground for construction without the carbon footprint of traditional cement or compaction methods.

A successful example: A research team from October University for Modern Sciences and Arts developed sand Lego-like bricks pressed from local sandy soil, which were then used to build a one-story structure without any burning. The bricks proved to be more climate friendly than traditional clay bricks. The structure was sturdy, good at isolation, and the bricks were half as costly as other materials.

And another: Builders in Siwa Oasis are combining traditional construction methods using karshif — a stone found by the Salt Lake in Siwa — to create cost-effective and climate-resilient buildings. Karshif, combined with other natural materials — silt, palm wood, and natural stone — can create strong, long-lasting structures.

AAC blocks are also an alternative: Sand can also be used to create autoclaved aerated concrete (AAC) blocks — also known as light white blocks. The blocks are lightweight and energy-efficient materials made from sand, cement, lime, and gypsum, and then cured with electric-powered autoclaving rather than burning. AAC blocks have several advantages including their ability to reduce a building’s energy consumption, as doubling AAC block and reflective glass in a structure can reduce energy use by up to 25% in residential and commercial buildings. These blocks are more costly than traditional bricks, but in the long term save energy and are fire resistant.

What’s the catch? There are challenges to using desert sand in construction including the lack of a regulatory framework for sand-based alternatives as many contractors and developers still stick to the familiar and tested options like clay bricks and standard cement. Desert sand is also too fine and smooth to use in construction, so without the right mix or stabilization techniques, structures would lose their strength and durability, according to an article by real estate developer Wegraz.

What’s next? “To standardize locally recognized criteria, the researcher underlines the necessity of further experimental investigations especially including Egyptian sand and regulatory actions that help to integrate masonry and sandbased concrete. The research supports the adoption of Lego-inspired building methods, modular and sustainable sand-based building materials, to enable quick and environmentally friendly urban growth,” the paper concludes.

Your top green economy stories for the week:

  • Localizing seed production: The Agriculture Ministry is in negotiations with several French and Italian companies to establish vegetable seed production projects in Egypt to stop relying on imports. (Al Borsa)
  • Egypt’s first green city: Sharm El Sheikh became the first Egyptian city to join the Local Governments for Sustainability’s global network of sustainable cities. (Statement)
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