Effect of MgO Injection on Smelting in a Blast Furnace

The effects of the simultaneous injection of MgO and magnesite powder on the combustion of coals, properties of the primary slag, and softening-melting properties of the burden were investigated. There were four aspects to the results that we obtained. First, MgO showed catalytic activity for dehydrogenation and carboxyl group removal from coal; as a result, with increasing MgO, the combustion ratio and pyrolysis ratio of the coal investigated improved. Notably, when the content of MgO increased from 0% to 3.21%, the combustion ratio increased from 67.75% to 75.73%. Secondly, the MgO distribution in the slag sample was close to that in the standard slag after melting for 10 min. After 50 min, the difference in MgO content between the slag and standard slag samples was less than 1%. Thirdly, with an increase in the content of MgO, the short-slag feature of the slag was obvious, the viscosity fluctuated wildly, and the melting temperature increased significantly. It is proposed that the properties of the primary slag could be improved by decreasing the MgO content. Finally, with the increase in the MgO added to the burden, the softening-melting properties of the burden degraded. When the MgO content was 0.86%, ΔPmax was only 2.04 kpa, and S 59 kPa·°C. However, when the MgO content was 2.61%, ΔPmax was 20.00 kPa, and S 1349 kPa·°C. Therefore, the technology of MgO injection into tuyeres with pulverized coal was beneficial for blast furnace operation.

Study on Properties of Re-Bonded Magnesium Zirconium Refractory Materials and Materials Application

Nineteen eighties, the sintering zone of cement rotary kiln and transition belt use main magnesia chrome brick because of its excellent performance, but the Cr6+ is carcinogenicity, which causes great harm to the air, water pollution, animal or human. Therefore, new basic refractory material of free of chrome began to be developed. This test, the raw material is made up of fused magnesite particles (particle size 0 to 3 mm), fine fused magnesite powder with the size less than 200 meshes and fine fused magnesia-zirconia’s powder with the size less than 320 meshes, polyvinyl alcohol and calcium lignosulfonate liquor being used as the combiner. This paper discusses the effect of sinter temperature on sinter character of products.

Experimental Study on the Re-Bonded Magnesia - Zirconia Refractory for New Dry Process Cement Kiln

The use of magnesia-chrome refractories of the cement kiln can generate harmful hexavalent chromium in the environment and be hazardous to your health, so the study on the instead of magnesia-chrome refractories have become urgent issues. The raw material is made up of fused magnesite particles (particle size 0 to 3 mm), fine fused magnesite powder with the size less than 200 meshes and fine fused magnesia-zirconia’s powder with the size less than 320 meshes, polyvinyl alcohol and calcium lignosulfonate liquor being used as the combine. This paper discusses the effect of sinter temperature on sinter character of products.

Characterization of Mg-Al Spinel Synthesized with Alkali Corrosion Slag from Aluminum Profile Factory

Mg-Al spinel has been synthesized by using alkali corrosion slag from aluminum profile factory, decomposed magnesite and used MgO-C brick as the main raw materials. The influence of decomposed magnesite and used MgO-C brick powder after calcinations process on crystalline constitution and micro-morphology of synthesized Mg-Al spinel specimens are discussed. The synthesized specimens are characterized by XRD and SEM, and the crystallinity of crystalline phase is calculated by X' Pert plus software. The experimental result shows that the crystalline phase periclase increases with the increasing of magnesia generated by used MgO-C brick powder. The crystallinity of crystalline phase is maximum when the addition of used MgO-C brick powder after calcined at 800°C is 30wt%. Magnesia generated by sintering decomposed magnesite powder at 700°C showed more effective than magnesia generated by used MgO-C brick powder to react with impurity in alkaline corrosion slag.