Vertical Kiln Bauxite for Refractory Raw Materials

Xiaoyi City Jingang Refractory Materials Co., Ltd. was established in 2019 and produces refractory raw materials in Xiaoyi, Shanxi Province, China. Its vertical kiln bauxite is calcined in a shaft kiln. The company also supplies mullite, kaolin, jiao bao shi and castable materials, and it describes itself as a high-tech enterprise with a municipal technology center.

A shaft kiln is a cylindrical kiln with preheating, calcination and cooling zones. Raw material and gas flow move in counter-current convection: the ore descends from the top while the gas rises from the bottom. The kiln has identical inner diameters at the top and bottom, a simple robust structure, low capital investment, efficient heat utilization and low fuel consumption. Annual capacity exceeds 60,000 tonnes.

The process starts with manual sorting and grading of the raw ore, then screening out soil powder and impurities. Ore of 25 to 150 mm enters the kiln for counter-current calcination, followed by bottom cooling and discharge, manual sorting, crushing and screening. The output is aggregate or fine powder. Only large lumps can be fired, because powder and crushed ore have poor permeability.

The grades range from 90 to 70, with alumina content of at least 90, 88, 85, 80 or 70 percent. Iron oxide is limited to 1.5 to 1.8 percent, titania to 4.0 percent, CaO plus MgO to 0.4 to 0.5 percent and K2O plus Na2O to 0.25 to 0.30 percent. Bulk density ranges from 2.85 to 3.40 g/cm3 and water absorption from 1.7 to 3.5 percent.

Vertical kiln bauxite is positioned for cost-sensitive applications such as low-grade castables, standard high-alumina bricks, bauxite cement and foundry coatings. Its advantages include low production cost, a simple process, ample supply and a large sintered block with good wear resistance. Its limitations include poor compositional uniformity, mixed burnt quality, high manual sorting labor and lower mullitization than rotary kiln or homogenized bauxite.

For a vertical kiln bauxite order, buyers should confirm the grade, the alumina content, the impurities, the bulk density, the water absorption, the sizing and the application. It is also useful to agree on the sampling and inspection method, because the kiln produces natural variation between lumps and bags. Xiaoyi City Jingang Refractory Materials Co., Ltd. can be reached at della@kingconref.com or kinder@kingconref.com. Send the grade, size and quantity, and the team can confirm the vertical kiln bauxite and the next steps.