In the tide of global carbon reduction, the cement industry, as a representative of high carbon emissions, has attracted wide attention for its emission reduction actions. However, some carbon reduction measures have been questioned as "face-saving projects", that is, they seem to be environmentally friendly on the surface, but in fact they have not brought substantial carbon emission reduction effects. Faced with such doubts, how should the cement industry really achieve carbon emission reduction?
"In order to promote the carbon neutralization of the cement industry, there have been some carbon reduction pioneers. Due to inadequate theoretical preparation and product market development, there have been some face-saving projects. This is an indispensable exploration in a huge innovation." Shen Weiguo, a researcher and doctoral supervisor at Wuhan University of Technology, said.
According to Shen Weiguo, the carbon emissions of the cement industry mainly come from six levels. The general situation is 6LCC: the reduction of national infrastructure scale, the reduction of building concrete consumption, the reduction of cement consumption in concrete, the reduction of clinker consumption in cement, the reduction of carbon emissions in clinker production process and the substitution of new cement or cementitious materials with low carbon emissions. The emission reduction of the
cement industry is an overall measure:
the first is to reduce the scale of infrastructure construction: after the peak period of infrastructure construction in developed countries, the service life of buildings is longer, the per capita cement consumption is lower, and the trend of reducing the scale of infrastructure construction in China has been formed.
The second is to reduce the use of concrete: use more materials that are easy to recycle and biomass materials, as well as structures with high strength and more reasonable design, to reduce the amount of concrete.
The third is to reduce the amount of cement in concrete: give full play to the interlocking effect of coarse aggregate and reduce the amount of cement in concrete.
Fourth, reduce the amount of clinker: stimulate the activity of metastable auxiliary cementitious materials, reduce the amount of clinker, and fully develop the potential of Chinese enterprises in this regard.
And fifthly, prepare that low-carbon clinker, namely prepare the low-carbon clinker by adopting non-Ca CO3 calcareous raw materials, reduce fuel carbon emission and the like.
Sixth, develop low-carbon cement: research and develop new cement or cementitious materials with lower carbon emissions, such as alkali-activated cementitious materials, biomass cement, etc.
However, we need to pay attention to the fact that under the current situation, it is obviously unrealistic for a cement enterprise to invest in technology and equipment innovation simply for energy saving and emission reduction.
"Only energy-saving and emission reduction technologies with cost reduction and efficiency enhancement and low investment are rational choices at present." Shen Weiguo emphasized that "steel slag phase separation clinker" is the best choice in the current industry situation. The technology of "
steel slag phase separation clinker" is to put the unground steel slag into the kiln system for calcination, forming a gradient clinker containing three layers of different phases with the reconstructed steel slag as the core, the high-speed rail clinker as the transition zone and the ordinary clinker as the main body, so it is called steel slag phase separation clinker.
Shen Weiguo said that "steel slag phase separation clinker" may be the most economical investment, the most obvious emission reduction, the greatest energy saving and the most significant comprehensive benefits in the comprehensive utilization technology of steel slag so far, and its application prospect is very broad. If the technology is fully promoted and applied, it will not only convert 160 million tons of cheap steel slag into high-quality clinker at low cost every year, but also produce 132 million tons of carbon emission reduction, with considerable direct economic and environmental benefits.
In a word, although the road of carbon emission reduction in cement industry is full of challenges, through continuous technological innovation and industry practice such as "steel slag phase-separated clinker", we have reason to believe that the cement industry can surpass the "face project", realize the real green transformation, and explore a sustainable way of cement concrete development. To leave a cleaner and more sustainable planet for future generations.
China Cement Network will hold the " 2024 China Cement Double Carbon Conference and the 12th Energy Conservation and Environmental Protection Technology Exchange Conference " in Wuhu Conch International Hotel on October 24-25. The conference will focus on the core issues of low-carbon development and green upgrading in the cement industry, discuss the application of energy efficiency improvement and energy-saving and carbon reduction technologies, and how the cement industry can use the carbon trading mechanism to promote its low-carbon transformation. At the meeting, Shen Weiguo, a researcher and doctoral supervisor of Wuhan University of Technology, will give a wonderful report.
