Macau Matters | Teaching an old dog new tricks

Richard Whitfield

Based on research from Rutgers University, Solidia Technologies (www.solidiatech.com or Solidia Video) is commercializing a new way to make concrete which can dramatically reduce the environmental impact of this major global industry. Like my earlier (23 October 2019) article about the Hazer Group, this is another great example of how farsighted business-people are learning how to profit from improving our planet instead of destroying it. Again, I wish we had more university-industry collaboration in Macau that is similarly focused on counteracting climate change.
Human synthesis of rock-like substances for use to make shelters dates back to Neolithic times. Structures made from cob and adobe and other mixtures of sand, stones, mud and other binding agents have been a feature of many cultures for millennia. The Greeks, and later the Romans, knew that if a mixture of volcanic ash and cementitious materials, sand and stone was wet down with water a chemical reaction would occur to turn the material into concrete. Portland cement, the principal binding agent used in modern concrete was developed in the mid-1800’s. It is derived mostly from limestone, a carbonate sedimentary rock formed from the skeletons and shells of marine animals.
To make Portland cement nowadays, limestone is crushed with clay and then burnt at high temperature (1,450oC) to initiate the formation of calcium silicates and other cementitious materials and to release carbon dioxide (CO2) as a waste gas. Cement production is responsible for around 8% of global energy consumption and accounts for 5% of the CO2 now being released into the atmosphere.
Most people have seen how Portland cement is mixed with sand, stone and water to make a slurry in concrete batching plants and then transported by cement-mixer trucks to building sites where it is pumped into molds and then hardens over several days, whereupon the molds are removed. The water triggers a chemical reaction that converts the Portland cement into the rock-like material we call concrete. The sand and stone are largely “filler” materials and are not involved in this chemical process, but they do contribute to the final strength of the concrete.
Solidia has developed and patented two fundamental changes to conventional cement/concrete production and use. Firstly, it has developed a new way to make Portland cement from limestone which significantly reduces the energy needed and eliminates 30%-40% of the waste CO2. Secondly, it has found a way to use CO2 (mixed with some water) to initiate the chemical reaction to turn cement powder into rock. Thus the CO2 generated during the process of turning limestone into Portland cement is no longer a waste, but can be reused to trigger the reaction to gradually harden the cement, sand, stone slurry into rock (concrete). This CO2 is thus locked into the structure of the concrete so it is never released into the atmosphere.
If fully adopted by the global cement/concrete industry, Solidia’s technology has the potential to reduce global CO2 emissions by 1.5 gigatonnes/year. It could also reduce the water consumed to make concrete by 3 trillion litres/year. As an added advantage, Solidia concrete fully hardens in 1 day, and not the 20-30 days that conventional concrete takes to fully harden.
The Solidia technology is well proven and it has won several industry awards and its investors include Kleiner Perkins and other investment funds and LafargeHolcim, the world’s largest manufacturer of building materials, and Air Liquide a major global industrial gases company.
Given the large amounts of cement/concrete used in Macau each year, do you think we could convert the local industry to use this new technology? Yet another way that Macau could become a world leader, if only we had the will.