The improvement or innovation of a certain link cannot fully achieve the "two-carbon" goal. We need to comprehensively measure from one industry or even multiple industries, consider walking on multiple legs, multiple technologies, and multiple links Work together to reach the goal in the end.
The national "dual carbon" goal has put forward higher requirements for low carbon emission reduction in all walks of life. In the past 30 years, the cement and concrete industries have made great contributions to the national infrastructure. To achieve sustainable development in the future, it is an inevitable choice to strengthen the research and development of low-carbon cementitious materials.
A few days ago, in an interview with this reporter, Hunan University professor Shi Caijun said that the development of low-carbon cementitious materials should be driven by the "double carbon" goal, with multiple legs and multiple technologies. , Multiple links are carried out synchronously at the same time.
European and American countries began to calculate carbon footprint as early as 2000, collecting and coordinating the corresponding energy consumption and carbon emission information during transportation, production, processing and storage under my country's specific national conditions. Accurate calculation of the carbon footprint of industries such as , concrete and other industries is very important and significant.
"The carbon emission or carbon footprint of concrete per unit volume or weight is relatively very low, but it cannot be judged as a completely low-carbon material because of its low carbon emission." Shi Caijun believes that , the so-called low-carbon materials should be the conclusions drawn in the case of comparison, such as the process used compared with the conventional process, or the use of specific materials to build buildings compared with buildings built with traditional materials. "With the same unit area, steel structure and reinforced concrete are used to calculate the entire carbon footprint, and the comparison method is more meaningful and valuable."
Neutralizing the target has a significant impact.As cementitious material widely used in civil engineering, water conservancy, national defense and other projects, the carbon emissions of the cement industry account for about 9% of the total carbon emissions in the country, and it is the main source of carbon dioxide emissions in the manufacturing industry. The development of some cementitious materials with a lower carbon footprint is the direction of the industry's efforts.
"Alkali-activated cementitious materials have many advantages, especially sulfate corrosion resistance and groundwater corrosion resistance. Groundwater corrosion in southwest my country is extremely serious. At present, high-speed rail tunnels, subways, and underground piles in this area may all be Faced with the above problems, this material is also more suitable for the saline-alkali land in the northwest area of . Several deans of Qinghai University made a report a few years ago and found that many conventional cement concrete buildings in Qinghai suffered severe corrosion after three or five years.” Shi. Cai Jun believes that "alkali-activated cementitious materials are very suitable for application in groundwater corrosion, saline-alkali soil corrosion and marine environment. Although there are some technical problems and high production costs, its engineering service life can be extended several times. In the long run, , is a very suitable material."
"The other is how to use carbon dioxide to achieve the purpose of curing concrete." In this regard, Shi Caijun introduced that if the carbon dioxide generated in the process of firing cement is recarbonized to form calcium carbonate, Such a reciprocating cycle can actually consume a lot of carbon dioxide. "In the process of realization, some people questioned that the amount of carbon dioxide consumed by curing concrete with carbon dioxide is very small. In fact, I have been doing research on carbon dioxide utilization since 2000. Maybe this is an item that can really be promoted at this stage. Carbon dioxide utilization technology.”
In addition, the application of steel slag is also considered. Shi Caijun introduced that although the steel slag is currently more troublesome to use due to the low energy consumption, stability and activity of grinding, if carbon dioxide carbonization technology is used to directly turn it into a carbonized product and become an auxiliary cementitious material, it can also achieve the best possible results. effect of optimal use.
Shi Caijun said that the improvement or innovation of a certain link cannot fully achieve the "dual carbon" goal. We need to comprehensively measure from one industry or even multiple industries.Consider walking on multiple legs, multiple techniques and multiple links are coordinated, and finally the goal can be reached. Although there is no cementitious material that can completely replace Portland cement in the building materials industry at this stage, on the other hand, the use or preparation of low-carbon cementitious materials with different characteristics according to different environments and needs is very important to the industry. Achieving carbon reduction is significant.
China Building Materials News reporter: Wu Yue
Editor in charge: Ding Tao
Proofreading: Zhang Jian
Supervision: Han Fengfeng
