During the Sixth Five-Year Plan period, it was first promoted and applied on small ladle bricks with the price of magnesium

During the Sixth Five-Year Plan period, it was first promoted and applied on small ladle bricks with the price of magnesium

Following the aluminum-magnesium ramming material, China has developed aluminum-magnesium castables using high-quality high-alumina bauxite clinker and sintered magnesia as raw materials and liquid water glass as a binder. During the period of "Sixth Five-Year Plan" for exporting magnesium bricks, the castables were first promoted and applied on small ladle bricks and achieved good results. For example, in a steel plant in Hebei, 10t and 14t ladle bricks use aluminum-magnesium castables combined with water glass. The average package age is 109.7 times [12], which is more than 8 times the clay brick lining. A 15t and 13t ladle brick of a steel plant in Heilongjiang uses aluminum-magnesium castables, the package age is 53 times, and the clay liner brick is only 6-10 times.

During the "Seventh Five-Year Plan" period, the technology of integrally cast lining of ladle bricks was listed as a key new technology promotion project of the former Ministry of Metallurgy and promoted nationwide. By the third quarter of 1987, most of the medium and small ladle bricks (capacity below 45t) for converters below 30t in China had adopted integral casting linings. The overall casting lining life is more than 40 to 60 times, and some small ladle bricks can reach 90 times [13]. The consumption of refractory materials and the cost of linings have been greatly reduced, and obvious economic benefits have been achieved. The physical and chemical indexes of water-glass and aluminum-magnesium castables for a steel ladle brick of a steel plant are Al2O3 75.20%, MgO 9.47%, SiO2 10.25%, bulk density (110 ℃ × 24h) 2.67 ～ 2.73g. / Cm3, and the flexural strength at room temperature (110 ℃ × 24h) 14.9MPa.

Magnesium brick price

In addition to aluminum-magnesium ramming materials and aluminum-magnesium casting materials, China has also developed aluminum-magnesium unfired bricks combined with water glass, which is used on ladle bricks and has a longer life than traditional aluminum silicate ladle bricks. The 160t ladle bricks of Benxi Iron and Steel use aluminum-magnesium non-fired bricks, with an average life of 40.56 times, which is more than double the use of third-grade high-aluminum bricks (18.5 times). The average service life of 20t ladle bricks of Tianjin No. 3 Steelmaking Plant using aluminum-magnesium unfired bricks is 38.8 times, reaching 55 times, which is more than 4 times the service life of clay-lined bricks (9 times).

The physical and chemical indexes of the water glass bonded aluminum-magnesium unfired bricks produced by a plant are: Al2O3 68.46% ～ 74.07%, MgO 7.65% ～ 12.32%, SiO2 9.02% ～ 13.37%, Fe2O3 1.12% ～ 1.83%, and bulk density 2.48 ～ 2.86. g / cm3, apparent porosity is 16% ~ 23%, compressive strength at room temperature is 55.6 ~ 123MPa.