On May 25, 2023,Shangang Rizhao Iron and Steel PlantFor the 2#5100m blast furnace intermediate repair project, West China Science and Technology Group will undertake the construction of covering agent spraying and blast furnace wet injection lining. The project has achieved a number of technological breakthroughs: 1, efficient and safe. The first large blast furnace non-stop furnace injection lining; 2, fast repair production. The planned construction period is 36h, the actual construction period is 33.5h, and it is completed 2.5h ahead of schedule. 3. Cost reduction and efficiency increase. Repair to the designed thin-walled furnace type to achieve green and low-carbon operation of the blast furnace.

1.2#5100m Blast Furnace Medium Repair Construction Process

On May 25, 2023, the 2#5100m blast furnace of Rizhao Iron and Steel Plant of Shandong Iron and Steel Co., Ltd. began to enter the medium repair construction. After the envelope and top equipment were removed, the covering agent was sprayed by Huaxi Science and Technology, and the high-performance thermal insulation and thermal insulation gas protective covering agent developed by Huaxi was used to cover the furnace charge with pressure fire. In response to the problems of high temperature and large gas in the furnace, the West China Project Department has formulated effective safety assurance measures, established a safety management team and an emergency rescue organization, and the construction personnel in the furnace wear labor protection equipment such as heat insulation protective clothing and ventilators., Arrange full-time safety officers to conduct on-site inspections, and set up emergency rescue equipment to ensure construction safety from multiple dimensions. The spraying effect of the covering agent exceeds expectations, the temperature drops to the acceptable range of the human body, and the gas value measurement meets the standard, which provides a guarantee for the safe construction of the furnace.

The spraying effect of covering agent is good, and the detection values in the furnace are up to standard. Shanghai Baoye enters the furnace for replacement.Section 7-9 cooling stave, the cooling stave replacement is completed, and the furnace body is lined by wet injection by Huaxi Science and Technology, with a planned construction period of 36h. the huaxi project headquarters was set up with kang zhibin, vice president of the group, and kan zhenghua, an expert in ironmaking technology,Construction coordination meetings have been held for many times to optimize the construction organization, carry out construction rehearsal in advance, and repeatedly check the safety load in detail. Each node of spraying construction can be controlled in advanceIt is completed in 2.5h, reaching the design furnace type, which provides favorable conditions for energy saving, emission reduction and cost reduction of 2# blast furnace operation.

2.West China Science and Technology sixth generation wet injection lining technology advantages

(1) The sixth generation of wet injection lining technology of Huaxi Science and Technology completely adopts sol binding, so that the binding between materials has affinity, the material structure has been further optimized, abandoning the traditional water-adding binding process, completely solving the traditional process of poor water material binding, easy to fall off after bonding phenomenon.

(2) According to the construction feedback over the past few years, the construction rebound rate is less than or equal to 5%, and no dust and toxic and harmful gases are generated during injection, so as to avoid the normal operation of TRT affected by dust.

(3) The lining formed by high-pressure injection forms a high-density lining body in the blast furnace lining, with low porosity, high density, corrosion resistance and wear resistance, so as to achieve the purpose of rapid slag hanging and rapid production.

(4) Stabilize the edge airflow and improve the blast furnace smelting intensity have obvious effect.

(5) Rapid recovery of reasonable furnace type, increase production, reduce energy consumption, is one of the most efficient and effective method of blast furnace longevity.

(6) Intelligent lining, energy saving and consumption reduction lining, the blast furnace after the furnace to produce nitrogen, and the furnace wall secondary combination of continuous intelligent maintenance of furnace type lining, so that the gas flow to the blast furnace center convergence circulation, so as to achieve the effect of energy saving and consumption reduction.

Huaxi Technology's sixth generation wet injection lining technology (patent number:201010179044.7) is one of the symbols of the development level of blast furnace long-life ironmaking technology, is the most efficient and effective method of intelligent lining, energy saving and consumption reduction lining. The technology to blast furnace furnace belly, furnace waist, furnace body injection, can quickly restore a reasonable furnace type, improve production, reduce energy consumption, after the furnace to produce nitrogen and furnace wall secondary combination, continuous intelligent maintenance of furnace type lining, fuel ratio and then reduce 3-5 kg/t, blast furnace performance of various indicators is good, adopted by domestic and foreign steel enterprises. At present, the market share of Huaxi spraying project is 69.76, firmly occupying the first place in China!

3. Advantages of West China Science and Technology Sialon High-strength Composite Injection Material

(1) The use of metal (Si/Al) ductility to achieve plastic forming, the use of nitriding and reducing atmosphere in the blast furnace to achieve the use of in situ synthesis of high-temperature reinforcement phase (Si3N4/SiAlON), and non-oxide substrate to form a perfect mosaic structure, while achieving:

◆ Excellent resistance to chemical erosion

The use of the process with self-repair function

◆Good thermal shock resistance

(2) With the metal-non-oxide composite material system as the substrate, through non-oxide surface modification, the use of sol-gel molding process to achieve:

◆Good liquidity

◆Fast drying performance

◆ Overall stability after drying

The sixth generation of West China Science and Technology SiLong high-strength composite injection material solves the defects of traditional cement combined with spray coating. It has excellent wear resistance, good chemical stability, higher flexural strength, better thermal conductivity, and high-quality slagging ability.

Rizhao Steel Plant of ShansteelThe 6th generation of West China wet injection lining technology adopted in the 2#5100m blast furnace medium repair project is an ironmaking blast furnace.Advanced technology with high efficiency and longevity, energy saving and consumption reduction, green and low carbon,In ShansteelMany breakthroughs have been achieved in the 2# blast furnace repair project, and valuable practical experience has been provided for the maintenance and quick repair of the super large blast furnace.