Singapore scientists develop cement made from mud and urine

Traditional Portland cement production technology still has disadvantages, creating a large source of greenhouse gas emissions, because raw materials must go through a high-temperature calcination process. To overcome, many modern technologies were born, the latest, with biotechnology just released.

The technology uses biological waste, mainly the two main raw materials are industrial carbide sludge and urea.

This is a technology developed by Singapore's Nanyang Technological University. The technology uses biological waste, mainly two main materials are industrial carbide sludge, a by-product of the production of acetylene and urea gas, which is derived from the urine of mammals such as cows or pigs. .

The sludge is pre-treated with acid to produce soluble calcium. Then urine is added to form a cement solution. Continuing to add special bacteria to that solution, it is responsible for breaking down urea to form carbonate ions. The next step, in a process known as "microbiologically induced calcite precipitation," reacts with dissolved calcium ions to form solidified calcium carbonate.

When the mixture is combined with sand or soil, the reaction takes place, the calcium carbonate will bind with the sandy soil and fill the voids in the material. The result is a solid, concrete-like mass of material that is waterproof and has the same color as the original sand or soil.