As an advanced grinding equipment, VRMs play avital role in the cement industry. This paper details the process flow, main equipment composition, and actual operation effect of the grinding systems of TRMK60.3 cement VRM, HRM58.4 raw meal VRM and HRM43.3M pulverized coal VRM adopted in Africa's first 10 000t cement production line, invested and constructed in Ethiopia. The production and operation results show that all vertical roller mill systems operate stably and reliably with excellent product quality: the output of the TRMK60.3 cement VRM system is stably maintained at 280t/h, the blaine of the product is >3 900cm₂/g, and the system power consumption is about 29.7kW·h/t; the output of the HRM58.4 raw meal VRM system ranges from 470t/h to 480t/h, the residue of the raw meal after grinding on an 80μm sieve is 16%, and the system power consumption is about 15.4kW·h/t; the output of the HRM43.3M coal VRM system is 80~100t/h, the residue of the pulverized coal  on an 80μm sieve is 6%, and the system power consumption is about 22kW·h/t. All production and operational indicators have reached the advanced level of the industry, and the system has good promotion and application value.

The low-carbon graded separate grinding process based on cement vertical roller mills, compared to traditional mixed grinding processes, offers significant advantages including a lower clinker factor, reduced energy consumption, decreased carbon emissions, and enhanced overall cement performance. This study analyzes the mechanism of the low-carbon graded separate grinding technology, which leverages differences in the hydration activity of various raw materials. It involves grinding raw materials separately to different particle sizes before mixing them to produce the final product. The research focuses on comparative experiments of low-carbon graded separate grinding, investigates the fineness strategies for grinding raw materials with different activities (such as slag, clinker), and proposes two graded grinding process solutions: a combined grinding system ("vertical roller mill pre-grinding + ball mill grinding") and a vertical roller mill finish grinding system. Engineering practices demonstrate that the application of a low-carbon graded separate grinding system based on cement vertical roller mills can reduce clinker consumption by 10%~15% and decrease CO₂ emissions by approximately 80kg/t while maintaining or even improving cement performance. This system also enables the production of ultra-fine slag powder with a specific surface area exceeding 600m₂/kg, establishing it as an advanced production process promoting green and low-carbon development in the cement industry.

The ball mill coal powder preparation system of a new dry process cement clinker production line with a capacity of 5 000t/d has problems such as low output (50~55t/h) and high energy consumption (32~33kW·h/t). A modification plan using the "vertical roller mill pre grinding + ball mill final grinding" grading grinding process is proposed, and the grading grinding process flow of vertical roller mill coarse grinding and ball mill fine grinding is introduced. During the renovation, a three roll vertical roller mill with a nominal diameter of 3 500mm and an external structure dynamic and static powder selector were used. An independent feeding shell was added to the original upper shell of the vertical roller mill, and simulation optimization was carried out on key parameters of the vertical roller mill. After the renovation, the average output of the coal powder preparation system increased by 100% (about 110t/h); The total power consumption of a single machine is 19~20kW·h/t, which is about 40% lower than that of a single ball mill for grinding, achieving the dual goals of increasing production efficiency and energy conservation and consumption reduction.

This study analyzes the significant influence of slag powder particle size on the mechanical properties of cement mortar when used as a raw material in cement production. Slag powders of different fineness levels were prepared using a vertical roller mill grinding test system. The intrinsic relationship between the particle morphology of vertical mill-ground slag powder, particle size, and cement mortar strength was systematically investigated through laser particle size analysis, scanning electron microscopy, and grey correlation analysis. The results indicate that the particle group of vertical mill-ground slag powder exhibits more pronounced polydispersity. Particles in the 0~5μm range primarily enhance the 7d early strength of cement mortar, while particles in the 5~10μm range contribute most significantly to the 28d later strength. The particles in the 0~5μm and 5~10μm ranges exhibit the highest correlation with the 7d and 28d activity indices of slag powder (0.842 and 0.716, respectively). The study also found that the particle size uniformity of vertical mill-ground slag powder decreases as the particle size increases. However, optimizing the proportion of particles in the 0~20μm range can significantly improve the mechanical properties of cement mortar, providing a theoretical basis for process control in the production of high-performance slag powder using vertical roller mill systems.

The implementation of digital-intelligent transformation in the cement equipment manufacturing industry can help reducing manufacturing costs and meeting the demand for customized products. This article analyzes the problems of low automation level, extensive management, and high cost in the cement equipment manufacturing industry as a typical discrete manufacturing industry, and proposes a three-stage implementation of the digital transformation path. The basic stage mainly focuses on consolidating standardized design, data collection, network coverage, and platform construction; In the intermediate stage, the focus is on breaking down data silos and achieving system integration and local intelligent decision-making such as ERP and MES; In the advanced stage, relying on digital twin, AI algorithm and industrial Internet platform, the independent optimization and supply chain coordination of the whole process equipment manufacturing are achieved. Research shows that the basic stage can improve production efficiency by 20% to 30%, and the intermediate and advanced stages will further achieve global intelligent manufacturing optimization. Finally, it is pointed out that industrial Internet, digital twins, artificial intelligence and other technologies are the key technical supports to promote the cement equipment manufacturing industry to achieve global intelligence.

To promote the intelligence level of waste heat power plants, and continuously update existing technological systems, the paper attempt to build a new hardware framework for intelligent operation systems based on existing DCS and MES systems, and integrate the entire data process, collect and analyze data based on the operation logic of waste heat power plants and the operating procedures of power plant operators. By combining knowledge graphs with neural network models, a data-driven intelligent operation technology model is established. Through training and iterative optimization, an auxiliary decision-making platform is used for practical testing, ultimately achieving the goal of replacing manual operation or expert systems. Efforts are made to build a fourth generation waste heat power plant operation technology system, and achieve intelligent autonomous operation of waste heat power plants, and improve operational efficiency, and reduce operating costs.

This paper compares and summarizes the main revision contents of the new standard GB175-2023 "General Portland Cement", aiming at the problem that the fineness of 45μm sieve of finished cement in some enterprises does not meet the requirements of the new standard, several technical improvement measures are put forward, and taking the semi-final grinding system of "roller press+ball mill" in a production line as an example, the technical improvement scheme of "material processing in different paths+partial separate grinding" is put forward. After adjusting the lining plate and activation ring of the ball mill, optimizing the grading of the grinding media and introducing coarse-grained mixed materials, the residue of the 45μm sieve of the cement finished product was stabilized at about 7%, which realized the compliance production under the new standard and provided a new path for the technical upgrading of similar production lines.

According to the high technical index requirements of nuclear power cement (C₃S content   ≤50%, C₃A content ≤3%, f-CaO content ≤1.0%), optimization and improvement have been carried out in terms of raw material selection(preferring pure silicon-based, pure aluminum-based, and pure iron-based materials), batching scheme design (KH=0.86±0.02, SM=2.8±0.1, AM=0.8±0.1), optimization of rotary kiln calcination process (e.g., reducing feed rate and kiln speed, increasing calcination temperature inside the kiln.), and adjustments in production process control(e.g., stabilizing the temperature of the pre-calciner, controlling sample testing and frequency , maintaining low level of the raw material homogenization silo). Based on the above optimization and improvement measures, four-component batching and an online analyzer were adopted to control the batching. The stability of the three rate values of nuclear power cement clinker was enhanced, and the heat of hydration and strength all met the technical index requirements of nuclear power cement. The production and preparation process of nuclear power cement clinker provides a reference for the research and development of special cement and helps cement enterprises transform towards the production of diversified cement products.

The burner serves as the core thermal equipment in the calcination system of cement production rotary kilns. Its precise positioning and the adjustment of air duct pressure are primary methods for optimizing the kiln's combustion process. This paper outlines the requirements for precise positioning of the burner in the vertical direction (y-axis), horizontal direction (x-axis), and axial direction (relative to the kiln inlet). It introduces measurement, positioning, and marking methods at the kiln inlet along with their implementation steps, and discusses considerations for adjusting the burner's position based on kiln operational needs. Regarding the fan configuration mode of four-channel burners, the key functions and adjustment considerations for each air channel's pressure are analyzed, providing operational optimization insights for achieving ideal combustion performance.

 This paper reviews the effects of active metal components, support structures, and preparation methods of catalysts on their catalytic performance in dry reforming of methane (DRM), and it also explores the research directions of DRM catalysts. The DRM technology has the capacity to employ CO₂ captured by oxy-fuel combustion in the cement industry to react with CH₄ for syngas production, thereby facilitating the utilization of industrial CO₂ resources. Catalysts are crucial for improving the conversion rates of CH₄ and CO₂ . Ni-based catalysts are widely used, but single Ni components are susceptible to deactivation due to carbon deposition. Bimetallic Ni-based catalysts (such as Ni-Co systems) can significantly enhance carbon deposition resistance and anti-deactivation ability while maintaining high activity. Supports directly influences the reaction efficiency and service life of catalysts. The design of micro-mesoporous composite hierarchical porous supports can balance the dispersion of active metals (micropores) and the diffusion efficiency of reactants (mesopores). In terms of preparation methods, optimizing the dispersion of active metals and metal-support interactions can improve catalyst activity and carbon deposition resistance. In the future, auxiliary technologies such as plasma and photocatalysis may be employed to activate reactants under mild conditions. Meanwhile, the coupling of DRM with renewable energy sources such as solar and wind energy should be actively explored to promote green and efficient energy conversion.

Retarding cement refers to a type of cement whose setting time is prolonged by adding retarders. This paper summarizes the definition, characteristics, and development history of retarding cement, and explores its specific production processes, including raw material composition and preparation, batching control, calcination and grinding, and addition of retarders. In response to the application challenges of retarding cement in high-grade highways, bridges, tunnels, high-temperature construction, and long-distance transportation, specific solutions such as optimizing material ratio design, enhancing environmental adaptability, and using high-strength materials are proposed. Practical applications have shown that the use of retarding cement can effectively extend the setting time of concrete, improve its workability and durability, ensure continuous construction without affecting later performance, and has broad market prospects.

This paper analyzes the internal and external factors affecting pulverized coal production and grinding power consumption in view of the problems existing in the MPF2116 coal mill system, such as low hourly pulverized coal production (28~30t/h) and high grinding power consumption (28kW·h/t), and proposes a transformation plan that focuses on improving the matching degree and operational efficiency of the coal mill’s grinding capacity, powder selecting capacity, drying and carrying capacity, and optimizing the flow field inside the mill; Implemented measures such as increasing the diameter of the coal mill rollers to > 1 900mm, optimizing the nozzle ring structure, upgrading the existing powder separator to an MV type high-efficiency low-resistance powder separator, and increasing the capacity of the main motor of the coal mill from 500kW to 630kW were implemented. After the transformation, the grinding, drying and separation capacity of the coal mill system was effectively balanced. Under the same coal quality and fineness, the hourly output of the coal mill was increased to >38t/h, the grinding power consumptionwas reduced by 4kW·h/t, electricity savings reached by 100×10⁴kW·h per year, cost saving were 1.8 million yuan, and the overall efficiency of the system was significantly improved.

 A cement grinding station adopting the "vertical mill pre-grinding + closed-circuit ball mill" process had low capacity utilization and remained in a state of shutdown and losses for a long time. Therefore, it decided to carry out transformation to switch production to high-quality fly ash. First, the operation status of the grinding system before transformation and the performance of fly ash raw materials were analyzed. On this basis, a transformation implementation path was proposed: the raw fly ash is separated by a classifier, the coarse fly ash is sent to the ball mill for grinding, and the collected dust (fine fly ash) is transported to the finished product warehouse. Furthermore, based on the theoretical analysis and calculation of the production capacity of the conveying system and grinding system, the following optimizations were made: the fly ash metering system was replaced; the gradation of the grinding media (balls) in the ball mill was optimized; P·O42.5 cement and first-grade fly ash were blended to produce masonry cement. After the transformation, the performance indicators and production efficiency of the products have been significantly improved: for the first-grade fly ash product: the specific surface area is about 400m₂/kg, and the average hourly output is more than 110t/h;for the M32.5 masonry cement product: the 3d compressive strength is ≥20.8MPa, and the average hourly output is more than 120t/h. This transformation has enabled the grinding station to turn losses into profits, demonstrating the technical transformation value of "low investment and high returns".

The processing area of a large 10-million-ton-per-year granite aggregate production line is characterized by complex terrain with intensive karst caves, steep slopes, and water systems, which makes it difficult for centralized plant planning and layout. Additionally, the land transportation costs are high and pollution is severe. After analyzing the topographic features of this project, a distributed modular planning and layout solution is proposed through comparative evaluation. A primary crushing area is set up near the mining site, while deep processing and shipping wharf area are established alongside the river. A "three-stage, one closed-circuit" crushing process (primary, secondary, and tertiary crushing with closed-circuit screening) is adopted, and a dual-channel water transport network is constructed. By implementing a low-carbon logistics system featuring "long-distance belt conveying corridor + wharf shipping," and utilizing advanced energy-saving and environmentally friendly equipment, the comprehensive logistics cost of the production line is reduced by 52%, with annual CO₂ emissions cut by 38 000 tons. This approach provides a model breakthrough for the planning and layout of large aggregate production lines in similar mountainous and riverside regions (such as the Yangtze River Economic Belt and the Pearl River Delta).  

Sand and gravel aggregates are essential raw materials for infrastructure construction. This paper takes a hard rock aggregate production line project in Northwestern China as an example to discuss the process flow comparison and equipment selection calculation methods during the pre-project design stage. First, the raw material characteristics and the performance of impact crusher, jaw crusher, cone crusher and applicable conditions of commonly used crushers were analyzed. Through comparison, a three-stage and one closed-circuit crushing process of primary jaw crusher + secondary cone crusher + tertiary cone crusher and closed-circuit screening was proposed, and parameters such as size reduction ration and opening outlet width(CSS) of each section stage. Then, base on the project  scale (annual output of 2.5million tons) and product requirement (5~31.5mm high-end aggregates and high-quality machine-made sand), the each stage crushing capacity and maximum circulation of the crushers are calculated separately. Finally, the hard rock aggregate crushing equipment type are selected based on the calculation results. Practical application of the project showed that the design scheme was consistent with the actual production process and crusher selection, and the product output and quality met the contract requirements. This can serve as a reference for the preliminary scheme design of similar hard rock aggregate production line projects.