With the increasing global concern about climate change, the cement industry, as a major carbon emitter, has received unprecedented attention in its carbon reduction work. As the largest cement producer in the world, China's carbon reduction progress not only has a direct impact on domestic environmental quality, but also is of great significance to the realization of global emission reduction goals.
On the road of carbon reduction, China's cement industry has made remarkable achievements. By effectively eliminating backward production capacity, promoting energy-saving technology and using waste heat to generate electricity, the level of energy consumption and carbon emissions in China's cement industry has been greatly reduced. However, facing the long-term goal of carbon neutrality, the industry still faces multiple challenges.
"China's cement industry carbon peak has been completed, carbon neutralization is a great undertaking to overcome difficulties, the difficulty is not small." Shen Weiguo, a researcher and doctoral supervisor at Wuhan University of Technology, said that the cement industry's carbon emissions are mainly divided into six sources: raw material carbon emissions; fuel carbon emissions; electricity carbon emissions; transportation carbon emissions; concrete life cycle carbon emissions; and carbon deposition.
In Shen Weiguo's view, the main difficulties for the cement industry to achieve carbon neutrality lie in:
First, reducing carbon emissions from raw materials: Carbon emissions from raw materials are the biggest difficulty for the cement industry to reduce carbon emissions, although carbon emissions can be reduced by using alternative raw materials such as carbide slag, steel slag and industrial waste gypsum. However, the supply of these alternative materials is limited and there are technical difficulties. To achieve complete carbon neutrality of feedstock carbon emissions, innovative technologies are needed, such as the use of solar energy to convert carbon dioxide into fuel and the development of non-calcium carbonate calcareous feedstocks.
The second is to reduce fuel carbon emissions: the comprehensive energy consumption of cement clinker in China is significantly advanced in the world, and some new production lines have reached the level of 95 kilograms of standard coal consumption per ton of clinker. The potential of emission reduction through energy saving has been basically exhausted, even if the preheater and calciner are further improved to reduce the consumption of several kilograms of standard coal, the emission reduction effect can hardly exceed 10 kilograms. The use of alternative fuels is an effective measure to reduce emissions, but the current replacement rate is still low. In the future, the complete replacement of clean fuels will be the key to achieve carbon neutrality of fuel carbon emissions.
The third is to reduce carbon emissions from electricity: the reduction of carbon emissions from electricity is relatively easy to achieve. With the popularization of clean energy, cement enterprises can further reduce carbon emissions from electricity by using clean energy such as wind power and photovoltaic power. In addition, with the reduction of grid emission factors, even if enterprises do not directly adopt clean energy, their electricity carbon emissions will gradually decrease.
The fourth is to reduce carbon emissions in the transport sector: although carbon emissions in the transport sector do not account for a high proportion in the life cycle of cement, with the green transformation of transport modes, such as increasing the proportion of sea and river transport, and promoting public transit rail and other measures, this part of carbon emissions is expected to be significantly reduced. When
cement is made into cement-based materials, it will adsorb CO2 , that is, carbon deposition. In theory, within 100 years after adding water to cement, Carbon deposition equivalent to more than 50% of the raw material CO2 can be produced. Steel slag, slag and phosphorus slag all have different degrees of carbon deposition.
Looking forward to the future, in order to achieve full carbon neutrality in the cement industry, we need not only the drive of technological innovation, but also the cooperation of policy support and market mechanism. By adopting non-carbon raw materials, alternative fuels, clean energy and optimizing transportation modes, the cement industry will gradually achieve a significant reduction in carbon emissions, thus taking a more solid step on the road of carbon reduction.
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.
