Light burned magnesia powder is an important refractory

Light burned magnesia powder is a kind of raw material with medium alkalinity and chemical activity. Besides being used as refractory and cementitious material, light burned magnesia powder is also used in other industrial fields. In addition, the development of converter slag splashing technology further expands the application scope of light burned magnesia powder. At present, the slag splashing furnace protection technology mostly uses the light burned magnesia powder into balls, including light burned magnesia powder balls, carbon containing light burned magnesia sub balls and carbon containing calcium containing light burned magnesia powder balls.

Light burned magnesia powder, referred to as light burned magnesia powder, is a kind of active magnesia obtained by calcining magnesite, brucite and magnesium hydroxide extracted from seawater or brine at 800~1000 ℃. Light burned magnesia powder is light yellow and light brown powder, with particle size mostly below 100 meshes. Magnesite crystal is very small, with a density of 3.07~3.22g/cm3, large lattice constant, many lattice defects, brittle texture, porous structure, high reactivity, easy to conduct solid phase reaction or sintering, and hardens by forming Mg (OH) 2 with water, with bonding ability.

Selecting calcination method and controlling light calcination temperature are important means to obtain good activity. With the increase of calcination temperature, the specific surface area of MgO decreased significantly. When the temperature is higher than 1000 ℃, the recrystallization rate of MgO accelerates, the dispersion degree drops sharply, and the activity becomes worse. Using different calcination methods and equipment at the same temperature is also an important factor affecting the activity of MgO. If fluidized bed furnace and suspension furnace are used for calcination, the light burned magnesia powder with maximum activity can be obtained by rapidly decomposing it in an instant. The tunnel kiln and the reflection kiln are used to calcine large blocks for a long time, which will often lead to surface over burning and internal raw burning, which will reduce the activity of light burned magnesia powder. Using rotary kiln to calcine granular magnesite, the situation is between the two, which can also keep the activity of light burned magnesia powder better.

1 The weight of each batch of finished products shall not exceed 120 t.

2 The samples for particle size determination shall be sampled before the batching, and the samples for chemical analysis shall be sampled after the batching. Take one sample for each 20 small bags (25kg) and one sample for each large bag (1000kg).

After the obtained particle size sample is fully mixed, 10~20g shall be sampled to determine the particle size. The test sample after mixing is reduced to 200g and sent to the laboratory for analysis.

3 In case of any unqualified or abnormal chemical composition in the inspection results, take twice as many samples from the same batch of products for re inspection, and the re inspection results shall be the final inspection results of the batch of products.