On October 24, the "2024 China Cement Double Carbon Conference and the 12th Energy Conservation and Environmental Protection Technology Exchange Conference" was held in Wuhu, Anhui Province. Xuan Hongzhong, Vice Minister of Conch Cement Operations Department, shared "Conch Cement Green Low Carbon Technology Innovation Research and Development and Application". Xuan Hongzhong said that in light of the market situation of the cement industry and the demand for high-quality and low-carbon development of Conch Cement, Conch will increase its research and development efforts in energy conservation and carbon reduction, green environmental protection, clean energy and low-carbon cement. The main research directions of Conch's technological innovation in the future are as follows: 1. Research and development projects of raw material and fuel substitution in the cement industry; 2、 Cement 
, Process (i.e., carbonate fractionation) CO2 emissions are about 58-62%, fuel combustion CO2 emissions are about 33-38%, and indirect CO2 emissions from electricity use are about 2-5%.
Focusing on the strategic requirements of "double carbon and double control", Conch Cement has increased the development and application of green low-carbon and other technical carbon emission reduction in the multi-dimension of "source carbon reduction, process carbon reduction and end carbon sequestration" to promote the high-quality development of the cement industry. The main carbon reduction and emission reduction technologies include:
carbon reduction at the source: carbon reduction at the source of cement production is achieved through the research and development and application of technologies such as the substitution of raw materials and fuels, the resource utilization of domestic sludge, and the use of clean energy. Carbon reduction in
the process: carbon reduction in the cement production process is achieved through the R & D and application of comprehensive energy efficiency technologies such as improving energy efficiency, oxygen-enriched combustion, building a "zero external power purchase" platform, upgrading ultra-low emission technologies, and digitalization and intelligent transformation of the system. Carbon sequestration
at the end: through the R & D and application of carbon dioxide capture, conversion and utilization technologies such as the preparation of combustible gas, mineralized building materials and CO2 energy storage, the "near-zero" carbon emission of cement production is promoted.
2. Technical transformation and engineering application
of comprehensive energy efficiency improvement 1.2.
After the transformation, the standard coal consumption per ton of clinker and the comprehensive power consumption basically reach the level 1 index stipulated in GB16780-2021standard.
3. Development of alternative fuel technology and its application
in cement kiln 1. Key points
of development of alternative fuel technology in cement kiln Considering that the combustion of alternative fuel requires sufficient oxygen, and avoiding the fluctuation of kiln working conditions caused by alternative fuel falling into the smoke chamber. Design position of alternative fuel feeding point:
scheme ①: top of tertiary air duct: near the interface of decomposition furnace;
Scheme ②: on the decomposing furnace column right above the tertiary air duct: 1-1.
Blend Alternative Fuel Success Story: TLH L Alternative Cement Kiln Fuel Application Project
The alternative fuels of the project are mainly: domestic waste, waste spinning and other alternative fuels; The disposal capacity of
alternative fuels is 20.1 t/H (including domestic waste 8.
At present, Conch Cement has promoted the application of alternative fuel technology in the production lines of more than 50 subsidiaries; the types of alternative fuels involved include RDF, industrial solid waste with calorific value, biomass fuel, waste rubber, carbon black, etc.; In the first half of the year, the use of alternative fuels accounted for about 11% of the total coal consumption.
4. Application
of SCR denitration technology in clinker line of cement plant 1. Arrangement
of conch high temperature and high dust SCR denitration system 2.
Exploration and demonstration application
of new technologies for energy saving, carbon reduction and pollution reduction in Conch 1.
Pilot test results of hydrogen-blended combustion in cement kiln:
hydrogen was blended in the calciner to replace coal powder in the calciner by 3.6% ~ 5.
The addition of hydrogen in the cone of the precalciner can not only replace 4% of the pulverized coal, but also reduce the NOx content at the exit of the precalciner by 25%, and the denitrification effect is obvious.
2.
Conch's second oxygen enrichment device has been put into use in BS Conch in October 2024; The oxygen-enriched oxygen production is about 1500Nm ³/H, and the oxygen concentration is about 99.3
.
The system design of carbon mineralizing materials: study the CO2 absorption and mineralization mechanism of carbon mineralizing materials, the influence mechanism of physical and mechanical properties, and optimize the material mix ratio. The effects of calcination process and ion doping on the reaction activity of carbon mineralized phase were studied to further improve the performance of carbon mineralized materials.
Develop the preparation method of carbon mineralized materials: study the influence of tail gas composition, temperature, humidity, reaction pressure and other factors on the mineralization reaction degree, strength and microstructure of carbon mineralized materials, and optimize the preparation process of carbon mineralized materials. Study on the durability of
carbon mineralized materials: study the durability of carbon mineralized materials such as salt spray corrosion resistance, and carry out corresponding performance characterization and testing according to the performance testing requirements of specific carbon mineralized materials, so as to provide feedback to guide the design and preparation of materials. In May
2024, the pilot test of Conch's first "CO2 Conversion and Utilization Technology"-Solid Carbon Fiber Board Demonstration Project was completed.
4. The research and development of new low-carbon cementitious materials and the pilot project
of Xi'an University of Architecture and Technology jointly use coal gangue activation to replace clinker, which can generally achieve the expected replacement of clinker by 30-40%. The 28 d compressive strength of low-carbon cementitious material reaches 42.
Breakthroughs in key technologies:
1.2.
At present, the activated coal gangue has passed the certification of new materials in Shaanxi Province, and the pilot test of the project has been completed, with an annual output of 6.
5.
Key technologies:
develop the pretreatment technology of alternative fuel densification molding at room temperature, improve the compression molding rate and upgrade the biomass molding equipment.
Develop a complete set of technologies for efficient and clean combustion of alternative fuels to solve the problems that alternative fuels can not be dispersed in the decomposition furnace and improve the synergy with pulverized coal combustion and raw material decomposition.
Combine with that production process of the cement plant, the waste heat flue gas of the cement kiln is fully utilize for drying the biomass raw materials, and the comprehensive utilization of the waste heat of the waste gas is improve.
It is verified that the process route of preparing alternative fuels by biomass pyrolysis is feasible, and a variety of biomass carbon products with adjustable calorific value (the low calorific value of the as-received base is 6000-7000 kcal/kg) are formed. After the biomass carbon is blended and burned in 60% proportion, the standard coal consumption index is better than first-level index. However, at present, the preparation cost of biomass charcoal is high, and the market benefit is not up to expectations.
6. The system adopts the gas-liquid mutual conversion carbon dioxide energy storage technology route initiated in the field of new energy storage technology in the cement industry, and uses the carbon dioxide captured on the cement production line as the medium for the energy storage system, so as to realize the recycling of carbon dioxide and reduce the cost of the energy storage system.
Optimize the shaft seal structure, maintain the pressure gradient, and ensure the safety and efficiency
of the turbine. Develop the micro-positive pressure self-sealing system for the closed system. The sealing form is labyrinth seal + carbon ring seal, which further reduces the heat loss of the working medium caused by the leakage of CO2.
Cement waste heat and new carbon dioxide energy storage coupling technology, make full use of waste heat resources
to research and develop high-efficiency low-resistance multi-phase heat exchange components, high energy density storage containers and pressure stabilization systems and multi-quality heat source power systems, etc., to achieve the full utilization of low-grade waste heat resources at 80-100 ℃ in cement kilns. 7.
resource utilization: that dry sludge is mixed and incinerate with coal, domestic garbage or cement raw material powder, and the like, so that thorough disposal can be realized. Sludge co-incineration can use the existing equipment and facilities to incinerate nearby, which saves a lot of costs and has low operation cost, and has been applied in some projects at home and abroad. The
domestic sludge pretreatment and resource utilization technology has the advantages of
heavy metal decomposition, no need of secondary treatment, harmful gas absorption, low heat source cost and low operation cost.
Chaohu Conch Sludge Drying and Resource Utilization Demonstration Project:
the moisture content of sludge after drying is ≤ 35%, and the lower calorific value as received is ≥ 1350kcal/kg; One ton of dried sludge can save 122.73 kg of standard coal and reduce carbon emissions by about
319.8.
Jining Conch Smart Energy Demonstration Park was selected as the seventh batch of demonstration enterprise parks for power demand side management in the national industrial field in 2023.
9.
Vehicle-road cloud system: The intelligent traffic management and control system for mining engineering machinery on the "cloud" is realized based on the core-end-cloud technology. The project has been popularized and applied in Tongling, Wuhu, Baimashan and Chizhou. Full-automatic loading system for bulk
aggregate: the top-mounted loader moves the material distribution, and the bulk truck does not need to move, which realizes the unmanned automatic loading of the whole process of bulk. The online rate of the system is ≥ 98%, and 29 full-automatic and 53 semi-automatic lanes have been implemented for aggregate loading.
"Candle Dragon" expert system: control algorithm PID, MPC, EID-MPC autonomy rate is 100%; key parameter stability is improved by 30%; free calcium standard deviation is reduced by 10%; operator labor intensity is reduced by 50%. It has been popularized and applied in more than 10 production lines such as Xing'an 2 # Line and external enterprises such as Hebei Jingye Iron and Steel Co., Ltd.
Intelligent management and control platform: It has been popularized and applied in more than 40 companies.
6. Conch's future development direction
of carbon emission reduction technology innovation and application The main research direction
of Conch Cement's scientific and technological innovation is based on the market situation of the cement industry and the demand for high-quality and low-carbon development of Conch Cement. Conch will strengthen the research and development of technologies such as energy saving and carbon reduction, green environmental protection, clean energy and low-carbon cement. The main research directions of Conch's scientific and technological innovation in the future are as follows:
1. Research and development project of raw material and fuel substitution in the cement industry; 2. Research and development project of cement clinker quality improvement; 3. Research and development project of energy saving and carbon reduction technology and equipment; 4. Clean and green energy R & D and manufacturing project; 5. Future carbon technology industry exploration project.
