Hydrogen energy replacing fossil fuel to calcine cement clinker is an effective way to save energy and reduce carbon emission in cement industry. Based on the theoretical calculation of thermal engineering, the theoretical combustion temperature and gas volume of different fuels such as hydrogen were analyzed, and a small suspension calcining test platform was built to simulate the combustion state of the calciner, and the feasibility of hydrogen energy replacing fossil fuels in calcining cement clinker was analyzed and verified. Results show that hydrogen has no additional theoretical gas volume compared to conventional fuel. Hydrogen-enriched combustion of coal or alternative fuels has a positive effect on reducing CO and NO_X in suspension calcination, thus promoting the utilization of inferior fuel. As a low-carbon fuel, Hydrogen can further play a high activity to solve the technical bottleneck of incomplete combustion and high NO_X background emission of alternative fuel in the calciner. According to the experimental results, for reducing fossil fuel consumption and carbon emission, the industrialization technical route of 20% hydrogen energy coupled with 60% alternative fuel is proposed to calcine cement clinker. Before this route is applied to practical projects, more in-depth pilot study is needed.

With the deepening of national carbon dioxide reduction work, the cement industry, as an important source of carbon dioxide emissions, has received widespread attention. This article introduces the classification of carbon emission sources and methods of carbon dioxide emission measurement in the cement production process. Carbon dioxide emission sources can be divided into direct emission sources and indirect emission sources, meanwhile methods of carbon dioxide emission measurement mainly include carbon dioxide emission calculation methods and carbon emission online monitoring measurement methods. This article provides an overview of the main technologies for carbon dioxide capture in the cement industry at home and abroad, with a focus on the current application status of oxygen enriched/full oxygen combustion technology in the cement industry. At present, the main technological paths for carbon dioxide utilization in the cement industry include concrete carbonation curing, waste slag mineralization utilization, and preparation of new carbon fixing materials. In the future, the cement industry needs to continue to make efforts in reducing carbon dioxide capture costs, optimizing carbon dioxide emission measurement methods, and efficiently utilizing carbon dioxide resources to further promote the achievement of carbon reduction goals in cement production.

A cement production line adopts a cement grinding double loop flow semi-final grinding system composed of RP170mm-140mm roller press and [?]4.2m×13m ball mill. During operation, there are serious problems such as severe wear on the roller surface of the roller press, poor material extrusion effect, severe system crust formation, unreasonable arrangement of connecting air ducts between the powder selection machines, high resistance of the dust collector, and severe reverse grading of the grinding body in the second bin of the ball mill. The system process has high power consumption. By taking optimization measures such as reducing the initial roll gap of the roller press, strictly controlling the moisture content of raw materials, controlling equipment air leakage, adjusting the internal structure and grading of the grinding material, the system crust was improved, the system resistance was reduced, and the production capacity of the grinding system increased from 200t/h to 230t/h. The electricity consumption of the cement production process decreased from 29kW·h/t to 25~26kW·h/t, and the energy-saving and consumption reducing effect was significant.

Adding a bypass ventilation system is an effective way to solve the problem of cement product quality deterioration caused by the use of solid waste raw materials in cement kilns. However, traditional bypass ventilation systems suffer from the waste of waste heat resources. In order to improve the utilization rate of waste heat resources in cement kilns, process optimization was carried out on the basis of the traditional bypass ventilation waste heat utilization system. By replacing the mixed ambient cold air with mixed BP boiler exhaust, the vast majority of gas waste heat resources were recovered, increasing the power generation capacity of the waste heat power plant. Taking a 5 000t/d cement production line waste heat power generation project as an example, the economic feasibility of two process flows was compared and analyzed. The results show that adopting the optimized bypass ventilation waste heat boiler flue gas circulation system can increase economic benefits by 2.962 7 million yuan annually, reduce exhaust gas emissions by 42 750 Nm³/h, and achieve significant social and economic benefits.

Pyro technology is the key to the large-scale and intelligent development of cement production lines. This article introduces a series of advanced pyro technology equipment, including TX-3 weak vortex low resistance cyclone, third-generation self-denitrification calciner, Sinowalk fourth generation grate cooler, independently developed and designed by TCDRI. Taking the Xuzhou Zhonglian 10 000t/d production line renovation project and the Saudi YAMAMA 12 500t/d production line relocation renovation project as examples, this article introduces the technical solutions for optimizing and renovating using advanced pyro technology equipment. After the renovation, the standard coal consumption of Xuzhou Zhonglian 10 000t/d production line has been reduced to 93kgce/t.cl, the comprehensive power consumption of clinker has been reduced, the heat recovery efficiency of the cooler has been improved, and the NO_X emission concentration of the gas at the outlet of the preheater is ≤ 50mg/Nm³. The renovation has achieved good results. The Saudi YAMAMA 12 500t/d production line relocation and technological renovation project has achieved phased results and is expected to be put into operation in 2025.

When a 5 000 t/d cement clinker production line adopts dry desulfurization technology, there are problems such as the desulfurization effect being greatly affected by kiln operating conditions, the thermal stability of the kiln system being affected by water desulfurizers, and the possibility of "sticking bags" in bag dust collectors at the preheater. Using conventional wet desulfurization technology, although the desulfurization effect is stable, there is a problem of environmental pollution caused by wet flue gas plume emissions. A comparative analysis is conducted on the three technical processes and working principles of wet desulfurization combined with wet plume gas treatment, namely "flue gas condensation, flue gas heating, and flue gas condensation reheating". After adopting the wet desulfurization combined with flue gas heating technology to treat wet flue gas emissions, the SO₂ emission concentration of the kiln preheater flue gas was ≤ 50mg/Nm³, the humidity content of the flue gas was <65g/kg, and there was no white smoke emission from the kiln preheater chimney, it achieved the expected transformation goals.

A cement factory plans to change the kiln size from ?4.8m×74m to ?4.3m×74m. In order to reduce the cost of transforming, the reconstruction scheme adopted the original supports and tyres, redesign and manufacture the double loose pads system. This paper focuses on the double loose pads system structure design, machining, on-site installation and daily operation and maintenance. The double loose pads system is mainly composed of inner and outer pads, retaining rings,  transition sleeve, etc. The design should ensure a certain gap value and slippage between shell, tyre and retaining ring. During maching, the transition sleeve should be stress-relief annealing treatment; when installing, the pads system and tyre must be pre-assembly with large sections of the shell; during maintenance, it should pay attention to the lubrication and gap value detection of the pads system and replace the pads in time. The transformation took 4 months. The rotary kiln runs stably after being put into operation, and the expected goal of the transformation has been achieved. 

This paper introduces the characteristics and development history of near-infrared spectral analysis (NIR) technology. Technical points that need to be noted when applying NIR spectral analysis technology to the quality detection and control of cement raw meal out of the mill are proposed. When the near-infrared spectral analyzer is installed at the airslide where the raw meal exits the mill, the sampler better be an automatic sample-taking and sending type. The sampling point should be as close as possible to the NIR detection point, and the NIR detection site should be kept in a slightly negative pressure state. The NIR analyzer needs to be cooled during operation to ensure that the NIR analysis results are within the allowable error range. The advantages and disadvantages of PGNAA neutron activation analysis technology and NIR analysis technology are compared and analyzed. The results show that NIR analysis technology has more convenient market access, more obvious comprehensive cost advantages, and simpler later-stage maintenance, has certain application prospects.

In a 2 500t/d cement production line, the preheater system has high resistance, large fluctuations in material composition, and steel fiber castables in high-temperature areas are prone to burn and fall off, resulting in poor ventilation, cyclic enrichment of harmful components, and incomplete combustion of pulverized coal. The system has serious scaling and clogging and frequent kiln shutdowns, which seriously affect the stable operation of the kiln system. To solve the problem of material scaling and clogging in the preheater system, technical transformation was carried out using anti-scaling microcrystalline nano materials. The actual field application shows that the microcrystalline nano material has good thermal insulation effect and a smooth surface. At the parts where the microcrystalline nano material is used, the surface temperature drops significantly, effectively solving the problem of scaling and clogging. At the same time, the output and quality of clinker are improved, and the standard coal consumption of clinker is reduced by 2.5 kg/t. The labor intensity of workers and the construction safety risk are greatly reduced.

The traditional method of monitoring the operational status of cement production equipment relies heavily on manual inspection, which has problems such as missed and false detection of equipment malfunction status, low informationization, and low work efficiency. Based on the technologies of industrial Internet of Things, edge computing, cloud computing, AI artificial intelligence, machine learning, etc., the solution for developing an intelligent online monitoring interactive platform is proposed, and the main functions of the device intelligent online monitoring system and the AI video intelligent middle platform are introduced. The system has been successfully applied to scenarios such as deviation monitoring of cement production conveyor belts, detection of blockages at the feeding port, monitoring of pulverized coal temperature and flame, and so on. It has achieved intelligent early warning and intelligent diagnosis of equipment malfunctions in cement production, reducing the frequency of equipment downtime and extending the service life of cement production equipment.

The tooth height of the double-toothed roll crusher is the main tooth structure parameter that affects its crushing performance. The material crushing state of the roll tooth structure with different tooth heights is simulated and analyzed by discrete element method. The analysis results show that with the decrease of tooth height, the position of material crushing gradually shifts to the lower roller tooth inclusion cavity, which avoids the crushing of large materials in the direction of larger size, thus reducing the tooth roller torque, but the reduction range of the tooth roller torque becomes smaller and smaller. The ratio range of tooth height/roll tooth center distance should be controlled between 0.6 and 0.7. In this range, not only the discharge particle size of the double-toothed roll crusher meets the design requirements, but also the sum of the torque of the double-toothed roll is small, which is beneficial to reduce the energy consumption of the crusher.

This artical takes a certain dust collection supporting concrete frame which is at 9-degree seismic fortification zone as the research object. A scheme using BRB buckling constrained support dampers for seismic energy dissipation technology, meanwhile another traditional seismic structural scheme is designed respectively for this supporting frame. PERFORM-3D assessment analysis software is used to calculate the elastic-plastic time history seismic dynamic force of the two structural models, and the seismic performance of the two design schemes is compared. The results show that buckling constrained braces have an effective energy dissipation and seismic reduction effect on this supportign concerete frame. The total earthqueke actions and story lateral drift ratio for structures using seismic reduction are distinct lower than non-seismic reduction structures under multiple or rare earthquake.Energy dissipation structure has better seismic performance and greater safety margin.  Compared with non-seismic reduction structures, seismic energy dissipation structure  has less engineering quantity and better economic benefits.

Strengthening compliance management in engineering project construction is a critical measure for mitigating construction risks and enhancing project quality and efficiency. This paper uses a cement production line construction project as an example to define and emphasize the importance of compliance management in engineering projects. It provides a detailed overview of the compliance technology roadmap from preparation to execution, covering essential steps such as risk assessment and management, compliance team establishment, identification of applicable laws, regulations, and standards, formulation of compliance policies and procedures, compliance training and education, as well as the establishment of monitoring and review mechanisms. Following the implementation of this compliance roadmap, the project achieved zero safety or quality incidents and no work stoppages or rectifications, while also advancing the clinker production timeline by half a month. This effectively enhanced project quality and safety, strengthened stakeholder trust, and underscored the critical role of compliance in ensuring that project goals and long-term value are met.

Geological disasters caused by mine geological and ecological environment problems have always been the bottleneck restricting the development of some areas. In order to repair the geological landform and reduce soil erosion, effectively eliminate geological safety hazards of abandoned mines and improve the green plant coverage of abandoned mines, an abandoned open-pit mine in Yangxin County, Hubei Province was taken as a reference case. This article analyzes the ecological and geological environment issues of the abandoned mine. Using the technology of ecological protection and restoration, the high and steep slope of the mine was treated by the comprehensive treatment strategy of ' slope clearing + retaining wall + drainage ditch + edge sealing wall + site leveling + guest soil spray seeding greening + soil covering greening '. The geological environment and ecological environment were restored, and the artificial greening landscape coordinated with the surrounding natural environment was formed, which achieved the purpose of ecological restoration and management. This research and engineering practice not only achieved the goals of ecological environment protection and vegetation restoration, but also explored a new path in the field of mining ecological environment restoration and governance, providing valuable experience for similar mining vegetation restoration.