A research group * by Professor Ippei Maruyama of the University of Tokyo has developed the basis of technology that can manufacture carbon-neutral concrete using only used concrete containing calcium (Ca) and carbon dioxide (CO2) and water in the atmosphere. bottom.This concrete can be recycled repeatedly, and is expected to solve the problems of resource depletion and waste generation and reduce CO2 emissions.
Cement, which is indispensable for the production of concrete, emits a large amount of CO2 during production due to the decomposition of calcium carbonate, which is the main component of limestone.In addition, there is a need for reuse technology for using cement / concrete-based waste generated as building waste as a new construction material. Development was difficult.
The research group has developed a new basic manufacturing technology that forcibly precipitates and integrates calcium carbonate between crushed used concrete particles.Only used concrete containing atmospheric CO2, water and Ca is used.Using this method, the used concrete can immobilize up to the same amount of CO2 as the CO2 emitted in the past, so the concrete becomes carbon-neutral (the amount of CO2 emitted and absorbed is the same).
This concrete is named Calcium Carbonate Concrete (CCC) and can be recycled as many times as possible to be a complete resource recycling type.This will enable the effective use of CO2, which is thinly spread in the atmosphere, and Ca in concrete structures, which are present all over the country, for local production for local consumption, and is expected to reduce CO2 emissions in the construction field. Will be done.In the future, it may be applicable to the production of concrete on Mars.
* NEDO Moonshot Project by Tokyo University, Hokkaido University, Pacific Cement Co., Ltd., Tokyo Science University, Utsunomiya University, Kogakuin University, Shimizu Construction Co., Ltd., Masuo Recycle Co., Ltd.
