It is a commonly known fact that production of cement is a process, which can cause severe damage to the environment, mainly due to the large amount of carbon dioxide that is released in the atmosphere by the factories.
Not long ago, we told you about ‘slag‘, the green cement, which is produced without any heating and resembles the ancient product the Romans used many years ago. Now, a scientist from Edinburgh College of Art developed a new green cement, the biostone, out of sand, bacteria and urine, which could potentially transform the industry into a highly sustainable one.
Peter Trimble is the person behind the invention. In his search for a solution to the world’s most pressing problems, depletion of natural resources and high energy demand, he developed a prototype that requires none of the above in order to produce an eco-friendly alternative to one of the most highly polluting, yet extremely needed materials- cement.
To make the precious biostone you need roughly two days. First, you have to start by deciding what shape you would like your final product to take, get a mold that would fit it and fill it up with sand. After that, you would have to add bacteria, which have been previously grown in a nutrient broth, and let the mix develop overnight. Once this is done, calcium chloride, nutrient broth and urea, the main-nitrogen containing substance in mammal urine, are poured into the mold. The bacteria absorb the calcium carbonate by using the urea and turns it into a hard mixture, that binds the sand inside the mold.
The scientist had to overcome quite a number of challenges in order to get the right consistency and to perfect the method, however the results were worth the efforts. He managed to successfully demonstrate how a highly energy-intensive and polluting method of producing the material can be turned into an extremely sustainable one.
The biostone is definitely comparable with conventional cement in terms of its physical properties, but the main difference is that the production process does not require any energy or heat, hence does not produce any greenhouse gases.
With his still proof-of-concept design, Trimble hopes to show the industry that there is a way to concur the emission problem without having to sacrifice on quality of the final product. The designer hopes that this biomaterial would set the scene for further research and innovation in the field of sustainable material manufacturing.
Image (c) Peter Trimble