Dashiqiao Hongkai Refractories Co., Ltd.
Contact number: +86-13841720502
Zip code: 115100
Site: Nanlou Economic Development Zone, Dashiqiao City, Liaoning Province
Office Address: Building No. 5, Fenghua Yihe Village, Dashiqiao City, 105
Light burnt magnesia powder is a kind of active magnesia obtained by calcining magnesite, brucite and magnesium hydroxide extracted from seawater or brine at 800 ~ 1000 C. Light-burned magnesia powder is a light yellow and light brown powder. Its particle size is mostly below 100 mesh. Its crystal density is 3.07-3.22g/cm3. It has large lattice constant, many lattice defects, brittle texture, porous structure and high reactivity. It is easy to carry out solid-state reaction or sintering. It is obtained by selecting calcination method and controlling the temperature of light-burning. Important means of good activity. With the increase of calcination temperature, the specific surface area of MgO decreases significantly. The recrystallization rate of MgO increases, the dispersion decreases sharply and the activity decreases when the temperature is higher than 1000 C. Different calcination methods and equipment at the same temperature are also important factors affecting MgO activity. If calcined in fluidized bed furnace and suspension furnace, it can decompose rapidly in an instant, and the lightly burned magnesia powder with the greatest activity can be obtained. Using tunnel kiln and reflective kiln as large blocks, the calcination time is long, and the surface is often overburned while the interior is burned, which will reduce the activity of light-burned magnesia powder. The calcination of granular magnesite in rotary kiln is between the two conditions, and the light-burned magnesia powder can also be obtained to maintain better activity.
Magnesium hydroxide is produced by reaction of light burning magnesia powder with water. Magnesium hydroxide MgO+H_2=Mg(OH)2 is formed in the first part of reaction between powder-like light burning magnesia powder and sewage. In the instant of reaction between light burning magnesia powder and sewage, harmful impurities such as silicon in sewage are treated, because magnesium hydroxide has buffering property. It has the characteristics of high activity, strong adsorption capacity, non-corrosive, safe, non-toxic and harmless.
Magnesium hydroxide can not only neutralize the acid in wastewater, but also precipitate copper, iron, chromium (111), lead and zinc plasma in water. It can be further removed by the adsorption of magnesium hydroxide, and the purpose of complete removal can be achieved. Niand Cd plasma can also be partially removed.