Magnesium oxide (MgO) varies in reactivity according to the temperature at which it has been produced. Natural magnesite is the raw material used, most commonly for industrial grades of magnesium oxide. Magnesite (MgC03) can be calcined to produce highly reactive magnesium oxide which is generally known as caustic calcined magnesite (CCM). At higher temperatures the resultant magnesium oxide is considerably less reactive and colloquially known as dead burned magnesite or dead burnt magnesite. Electric arc furnaces producing very high temperatures to melt the magnesite create fused magnesite or fused magnesia. Another source of magnesium carbonate is sea water brine, from which the magnesium salts are precipitated and then calcined to produce light magnesium oxide.
Calcined magnesite is a cost effective source of chemical grade magnesium oxide – used as an alkali for acid neutralisation in the process and subsequent effluent treatment. A range of purities are available along with a choice of particle size. 90% magnesium oxide is the most cost effective grade, whereas 94% magnesium oxide introduces the lowest unwanted non reactives. Fine particle sizes are more reactive than coarse powder but can be found less easy to handle during processing.
pH Adjusters in Water and Wastewater Treatment:
Calcined Magnesite is a cost effective source of chemical grade magnesium oxide used as an alkali for acid neutralisation, both in process and in subsequent effluent treatment. Our calcined magnesite has been used as a means of securing optimal pH for subsequent coagulation and clarification steps.
Magnesium Hydroxide can also be used as an alternative to caustic soda in wastewater treatment as a means of increasing the pH. Optimal pH is a necessity for ensuring the effective performance of microbial and coagulation steps in the treatment of industrial wastewater.
Dead Burned Magnesite (also known as Dead Burnt Magnesite)
Dead burned magnesite is widely used as a basic refractory material. It is produced in rotary kilns and has purities of 90-95% MgO. It is widely used for gunning/ramming mass for tundish linings and for fettling purposes. Dead burned magnesite can be supplied in lump for users to crush and grade, or in ready-sized form. Common sizings are 5-3mm, 3-1mm, -1mm, -0.5mm and DIN 70.
Fused magnesia is prepared in electric arc furnaces by fusing calcined magnesite. Fused magnesia is a high performance basic refractory becoming more widely used for its durability under extreme conditions.
Light Magnesium Oxide
Light magnesium oxide (magnesia) is a chemical grade magnesium oxide with low impurities. It has consistent reactivity due to its controlled surface area. Light magnesium oxide is used in the surface coatings and rubber industries.