Aiming at the technical bottleneck of energy efficiency improvement of CUCC(Xuzhou)
10 000t/d production line Ⅰ, a solution of pollution reduction and carbon reduction of pyro system was proposed. The five-stage preheater was changed to six-stage preheater for the first time in chinese cement industry. The calciner volume was expanded and self-denitrification technology was adopted to improve the efficiency of the main combustion area, the speed of rotary kiln was accelerated, and the cooler was changed to the fourth-generation cooler with middle roll crusher. After the transformation, the outlet temperature of the preheater is reduced by 83℃, the standard coal consumption of clinker is reduced by about 14kg/t.cl, the comprehensive coal consumption per unit product of clinker reaches and is lower than the level 1 index of GB 16780-2021 standard by about 4%, 43 000 tons of standard coal is saved every year, and the annual carbon dioxide emission is reduced by 108 000 tons. Meanwhile, the emission reduction technology of self-denitrification source is applied in the existing preheater tower. The NO_X emission is lower than 25mg/Nm³ required by the local environmental protection department, the ammonia consumption is reduced by 10 000 tons, and provide a technology demonstration for the new upgrading of cement manufacturing under the double carbon strategy background, double control of energy consumption and ultra-low emission targets.

CUCC(Xuzhou) 10 000t/d cement production line Ⅰ technical upgrade project adopted six-stage preheater, the fourth generation of cooler with middle roller crusher and other advanced technical equipment. The large scale of the original equipment bring great difficulties in demolition work. The safety risks of this project is high. The new equipment has high technical standards and it is not easy to be installed. The schedule of construction is tight. Through detailing specific demolition plan and equipment installation plan, establishing and improving safety management organization, strengthening safety management, implementing delicacy management for the whole process of the project and precise construction organization, the upgrade goal was successfully achieved.

It introduces the composition of unattended conveying system of cement raw materials from four aspects: precise positioning system of stacker/reclaimer, laser radar scanning system, safety protection system against collision and PLC control system. After field test, the system can realize the three-dimensional imaging of the stockyard, the unattended safe and automatic operation of the stockyard stacker, the reclaimer and the belt conveyor.

With the development of the roller press combined grinding system, the internal structure of the ball mill suitable for this system should be optimized. With the optimization and modification of the feeding device, the liners structure, the intermediate diaphragm, the dam ring, and the heat-proof material, the operation efficiency of the ball mill is effectively improved and the energy consumption of the ball mill is reduced.

LOMA-MLB hot gas generator is suitable for blast furnace gas. Through computer modeling and mesh division, the combustion of blast furnace gas in the hot gas generator is numerically simulated by using Fluent software to verify the air-fuel ratio and flue gas temperature reference value required for air distribution during hot gas generator commissioning. The simulation results show that the combustion reaction mass transfer process is basically completed, the experimental data is slightly higher than the heat value calculated by the simulation data, and the simulated combustion burnout rate is high. The maximum temperature of the combustion flame center is 1 595K, and the NO_x content at the outlet is only 0.008 6ppm. The design of the bluff body of the gas burner is conducive to the mixing of fuel and air and the continuous stability of the flame.

The three times of clinker nodulation in cement kiln during collaborative treatment of hazardous solid waste was analyzed, the chemical composition and physical properties of clinker ball were tested, and the effects of chemical composition of raw material and clinker in kiln, control of raw material decomposition rate, chemical composition of hazardous solid waste and trace heavy metal content of cooperative treatment and addition of calcium fluoride sludge on clinker calcining process were analyzed. To solve the problem, it was optimized by stabilizing the chemical composition of raw material and clinker, appropriately reducing the content of Fe₂O₃ of raw material and the decomposition rate of raw material in hot kiln, strengthening the control of harmful components such as Cl^-, R₂O, etc. At the same time, the influence of adding dangerous solid waste to improve the burnability of raw material was fully considered in the process of mixing and calcination. At last, it effectively solved the problem of frequent clinker agglomeration in the cooperative disposal process of cement kiln.

The effects of adding magnesium slag into raw meal on clinker calcination, roller mill system operation and the cement performance using it as admixture were studied through experiments. When the content of magnesium slag in raw meal is ≥8.0%, it can significantly improve the burnability of raw meal and significantly increase the compressive strength of clinker. The magnesium slag contains CaF₂, which can act as mineralizer and crystal seed and improve the burnability of raw meal. Using magnesium slag instead of limestone, slag and other non-active admixture in cement can improve the compressive strength of cement for 3 days without affecting the anti-shrinkage performance of cement.

It introduces the technological process and technical advantages of the limestone gypsum wet desulfurization system, analyzes the problems existing in the actual application of the system, such as low limestone purity, easy blockage and freezing of limestone slurry transmission pipeline, improper liquid level control method, sediment at the bottom of the desulfurization tower, and solutions. The production practice shows that the limestone gypsum wet desulfurization system has high desulfurization efficiency, low use cost, simple operation, stable and controllable operation. When the raw material mill is running, the SO₂ emission concentration can be controlled below 10mg/Nm³; When the raw material mill is shut down, the SO₂ emission concentration can be controlled below 30mg/Nm³, and the limestone gypsum wet desulfurization system can fully meet the desulfurization requirements of cement production.

It introduces structure and characteristics of the insulated tubular busbar. The insulated tubular busbar has large current carrying capacity, strong insulation performance, corrosion resistance, outstanding heat dissipation, low loss, high mechanical strength, long service life, simple structure and easy installation. Since the insulated tubular busbar was put into operation in a large cement production line abroad for three years, the actual operating voltage of the power distribution system was 14.5kV, and the full load operating current was about 2 700~3 100A. the tubular busbar system has operated safely, stably and reliably without any fault so far.

Based on the fire hydrant system design practice of a wind turbine blade plant in Brazil, it analyzes and compares the design differences about fire hydrant system in ABNT NBR Standard and Chinese Fire Protection Standard from five aspects: indoor fire hydrant system, outdoor fire hydrant system, fire water reservoir, fire pump and fire stabilized pressure pump. Some advices about how to design fire hydrant system for industrial project in Brazil are proposed.

The paper introduces the principle of the active power filter (APF) and studies the calculation method and selection of APF in the cement engineering project. The APF can reduce the harmonics with theoretical calculation and application in projects. Selecting APF reasonably with considering actual nonlinear load condition can achieve good energy-saving effect and get considerable economic benefits.

Alkali-activated cementitious material is an energy-saving and environmentally friendly building material. Its raw materials are widely sourced and its durability is uncertain. The research results on the durability of alkali-activated cementitious materials under sulfate attack, acid corrosion, carbonization and chloride ion penetration are reviewed. Alkali-activated cementitious materials have better durability than ordinary Portland cement. Some secondary components in raw materials (such as magnesium oxide) may have unknown effects on the durability of alkali-activated cementitious materials. The corrosion resistance of alkali-activated cementitious materials can be improved by refining the pore structure of alkali-activated cementitious materials and increasing the density of alkali-activated cementitious materials.