Introducing
Transforming CO2 Emissions into Carbon Removal Concrete Solutions
CO2-SUICOM stands as the world's pioneering eco-friendly carbon removal concrete,
boasting to negative CO2 emissions during its production.
This technology marks a significant stride in shifting from mere decarbonization (reducing CO2 emissions)
to proactive carbon usage (leveraging CO2 emissions).
CO2-SUICOM：CO2-Storage and Utilization for Infrastructure by COncrete Materials.
Ordinary concrete relies heavily on cement,
a major CO2 emitter during production.
CO2-SUICOM, or "SUICOM" for short, significantly reduces CO2 emissions by replacing over half of the cement with γ-C2S and industrial by-products.
Unlike ordinary cement, which solidifies with water, γ-C2S uniquely hardens upon reacting with CO2. In the carbonation curing chamber, this innovative mixture absorbs substantial CO2 before fully hardening, trapping the carbon permanently within. This process also includes a unique method of directly utilizing CO2 from power plant emissions.
While ordinary concrete emits 288 kg/m3 of CO2, SUICOM slashes this by 197 kg/m3 through material substitution. Further CO2 absorption in the carbonation curing chamber reduces emissions by an additional 109 kg/m3.
The total reduction amounts to 306 kg/m3, effectively reaching near-zero or negative levels (-18 kg/m3).
SUICOM matches or exceeds the strength of ordinary concrete. The carbonation process not only densifies the surface, enhancing abrasion resistance, but also maintains a near-neutral pH, making it more harmonious with plants, wildlife, and the environment.
Location : Karuizawa, Nagano
Application : block-wall, private residence
Year of completion : 2023
A private residence in Karuizawa, Nagano. Situated along the road lies the distinctive triangular property extending 110m in length. A creative solution was essential in securing privacy from passing traffic and pedestrians, while acting as a foil for basking in the natural surroundings.
The approach was to design concrete block walls that would serve as filter screens. The line of sight is orchestrated by adjusting the angles of each block, fine-tuned by overlapping two rows of blocks in some places. In areas with a single row, the view is set in one direction. With two rows overlapping, the view on the other side is visible only when the block angles in the front and back rows align; otherwise, the view is obstructed.
The material used for the blocks is “CO2-SUICOM,” which is made by replacing a portion of cement, with an industrial byproduct and adding a carbon dioxide-absorbing material for less CO2 emissions during production.
Approximately 2,050 blocks are staggered in parallel rows to create five 3m-high walls. The living space is designed to “fill in the gaps” in between. Calibrating the block angles by three degrees to fit each room condition ensures privacy in the bedroom and bathroom, while also providing a spacious ambience in the living and dining rooms. Ultimately, the design transpires into blocks arranged in a gradient-like pattern.
Photographer :
Takumi Ota, Masahiro Ohgami
Location: Osaka City, Osaka Prefecture
Application: Piers of Expressway (stay-in-place formwork)
Year of completion: 2024 (Planned)
Location: Yokohama City, Kanagawa Prefecture
Application: Solar panel elevated base, mounts
Year of completion: 2023
Location: Ube City, Yamaguchi Prefecture
Application: Solar panel foundation block
Year of completion: 2014
Location: Masuda City, Shimane Prefecture
Application: Pedestrian/vehicle path boundary block
Year of completion: 2013
Location: Nakano ward, Tokyo
Application: Balcony ceiling panel
Year of completion: 2012
Location: Fukuyama City, Hiroshima Prefecture
Application: Paving blocks, etc.
Year of completion: 2011
CO2-SUICOM was developed jointly by Kajima, Chugoku electric power,
Denka, and Landes, with Mitsubishi Corporation involved in supporting its commercialization.
It is a material that solidifies by reacting with CO2. CO2 emissions during production are about 1/6 that of cement.
Blast furnace slag discharged during steelmaking and fly ash discharged during thermal power generation can be used.
High purity CO2 of course, but in the past we have experience with carbonation curing of exhaust gas from factories with a CO2 concentration of 10-15%.
A facility (carbonation chamber) is required to absorb CO2 when the concrete has hardened to a certain degree.
Quality is equivalent to ordinary concrete. The concrete is low in alkali and environmentally friendly.
Since CO2 is fixed to the same degree as limestone (CaCO3), it will not re-leak in a typical environment.
At present, it is manufactured and sold only in Japan. In the future, we would like to manufacture and sell it overseas as well.
Costs will become higher, but will depend on the amount of CO2 fixed.
No, it is the name of the concrete.