Testing device expedites measurement of hardened concrete CO2 uptake

Sources: University of Tokyo; CP staff

University of Tokyo researchers have unveiled the concrete thermal gravimetry and gas analyzer, a boxlike device gauging carbon dioxide absorbed in hardened specimens. A concrete block placed inside the device is heated to 980°C, releasing CO₂ and other readily measured gases. The process takes about one-third of the time of the current measurement method, which involves finely ground specimens and opens a window for concrete to react with the air. Early concrete thermal gravimetry and gas analyzer results show that an accurate measurement can be taken even when CO₂ is not uniformly distributed in the matrix. 

“We developed a new machine which can measure how much CO₂ is fixed in concrete or cementitious material without having to crush it,” says Department of Architecture Professor Ippei Maruyama. “Until now, there wasn’t a simple method to measure the amount of CO₂ fixed in concrete, but with this device, we can shorten the time it takes to measure CO₂  and increase the accuracy of the measurement. This device requires a suitably large space and special safety considerations, so for now, there are some limitations to its application. However, after further tests, we hope to make this device commercially available, so that it can contribute to sound emissions trading in the concrete sector and support global efforts to reach carbon neutrality.”