The Refractory Features Of Magnesia Chrome Bricks

HomeHome Improvement

  • Author Julia Cheng
  • Published June 16, 2015
  • Word count 382

Chrome is an important refractory material. It can increase the refractory bricks erosion resistance ability to mirabilite (salt cake). Magnesia Chrome bricks have been used as refractories for rotary lime kilns, cement kilns, or similar uses for many years, because of their excellent corrosion resistance.

Magnesia chrome bricks exhibits good corrosion resistance, high melting temperatures, low thermal conductivity, good thermal strength, and excellent thermal shock resistance. The refractoriness of magnesia chrome brick is over 2000℃,and the refractory under load is a above 1550℃. It has good steady volume in high temperature , the performance under sudden cold and sudden hot is better than magnesia bricks.

Despite these advantages, magnesia-chrome based refractory linings also suffered a serious disadvantage. The chrome within the magnesia-chrome bricks can react with the lime and alkali to form hexavalent chrome. Hexavalent chrome is a toxic material requiring special disposal measures. Thus, the use of magnesia-chrome bricks results in costly disposal and remediation procedures at the end of their use.

Magnesia Chrome bricks include ordinary magnesia chrome brick, direct-bonded magnesia chrome brick, rebonded magnesia chrome brick, and semi-rebonded magnesia chrome brick.

Ordinary magnesia chrome brick is made from sintered magnesia and chrome ore and sintered at high temperature. It has a higher bulk density and stronger thermal resistance than the magnesia brick. It is used in cement rotary kilns, glass kiln regenerators, permanent lining of steel furnace permanent and refining ladle permanent lining of refining ladle.

Directe-bonded magnesia chrome brick is made of low impurity chrome ore and high purity magnesia and fired at high temperature over 1700℃. It has strong slag resistance and good performance under high temperature. It is applied in cement rotary kilns, electric arc furnaces, and non-ferrous metal furnaces.

Rebonded magnesia chrome brick is made with synthetic fused magnesia, shaped under high pressure and fired at ultra high temperature. It is used in tapping hole of AOD furnace, the lower vessel of vacuum chamber and snorkel of RH furnace, and the slag line of high temperature furnaces.

The Semi-reboned magnesia chrome brick is made from Fused Magnesia-Chrome melting grain, high purity fused and burned magnesia sands, and chrome ore through ultra high temperature. It has both the excellent thermal shock resistance of the direct bonded brick and the good corrosion resistance of the Fused Rebonded magnesia chrome Bricks.

Zhengzhou Sunrise Refractory Co., Ltd. is a refractory supplier from China, offering a wide range of refractory materials. The magnesia chrome brick from Sunrise is made from high quality sintered magnesia and refractory level chrome ore and has excellent refractory performance.

Article source: https://articlebiz.com
This article has been viewed 736 times.

Rate article

Article comments

There are no posted comments.

Related articles