Alumina Calcium

Alumina Calcium

Introduction to calcium aluminate:

Calcium aluminate is a series of inorganic compounds which are sintered by calcium oxide and alumina at high temperature. Because of its high hardness and high melting point, calcium aluminate is used in cement and fire extinguishing materials. Calcium aluminate products are divided into three categories: water treatment, slag remover and high aluminum cement. Calcium aluminate mainly uses acid solution method to produce water purification agent, which can save a lot of manpower and power, and can reduce cost greatly. It has the characteristics of simple process equipment and easy operation, and is an ideal raw material for production of polyaluminium chloride.

Electrofusion calcium aluminate is also called pre melting refining slag or pre molten aluminum calcium slag, which has been used in foreign countries, such as Korea, Japan, Europe and America. The chemical composition of calcium aluminate is uniform, melting point is low, melting speed is fast, and smelting time can be shortened; No fluorine, no erosion of lining and ladle; The structure is compact, does not absorb water, and it is easy to store and transport the warehouse; Because of the stable phase and fast slag forming, it can reduce dust pollution and stabilize refining process; It is beneficial to improve the quality of steel without impurities such as hydrogen, nitrogen and carbon. The curve function of the stability of the product with time is almost a straight line. The wave and serrated curve functions of medium and low grade products (sintered products and cupola products) are avoided.

Production method of calcium aluminate:

The production method of calcium aluminate is to divide bauxite and limestone into a ball according to proportion, and then send them to rotary kiln. After being cooled by forging at 1300 ℃, the crushing package is called calcium aluminate product.

The dissolution rate of alumina in acid solution is higher.

Calcium aluminate use:

The electrofusion calcium aluminate (pre melted aluminum calcium slag) is mainly used for LF furnace, flat furnace and converter ladle refining, removing impurities such as sulfur and oxygen in the molten steel, reducing the content of harmful elements and impurities in steel, and is suitable for general carbon steel, high carbon steel, high and low alloy steel. It has been used in foreign countries, such as Korea, Japan, Europe and America.

Application scope of calcium aluminate:

Calcium aluminate is mainly used in ladle refining of LF, open hearth and converter to remove impurities such as sulfur and oxygen in molten steel and reduce the content of harmful elements and impurities in steel. It is suitable for ordinary carbon steel, high carbon steel, high and low alloy steel.

Calcium aluminate can be used to make cement. Calcium aluminate cement containing calcium aluminate nanowhiskers has high specific surface area and good dispersibility in castables, which can reduce the amount of calcium aluminate cement in castables and realize low and ultra-low amount of cement in refractory castables. In addition, the calcium aluminate nano whiskers in calcium aluminate cement can play its bridging role, help to enhance the toughness and tensile strength of castables, and improve the high temperature performance of castables. Calcium aluminate cement containing calcium aluminate nanowhiskers can replace calcium aluminate cement and be used in cement-based reinforced materials, which can further improve the properties of materials.

In addition, it can also be used to prepare a silicon carbide - six calcium aluminate composite porous ceramic method. Calcium aluminate cement is used as calcium source, and foaming method is combined with calcium aluminate cement to achieve the rapid solidification of foam slurry to obtain porous billet. Then, the calcium hexaaluminate bonded silicon carbide material was produced by the reaction of calcium aluminate cement and alumina powder at high temperature to realize the preparation of silicon carbide calcium hexaaluminate multiphase porous ceramics. The invention has the characteristics of low density, high strength, strong alkali resistance and good thermal shock stability.

A kind of calcium sulphoaluminate mineral modified cement-based pore sealing material was prepared by using calcium sulphoaluminate reinforced Portland cement composite system and aluminum powder as gas generating agent. The invention adopts the single mineral coating technology, preferentially grinds the calcium sulphoaluminate and the resin together, makes the fine resin particles adsorb on the surface of the calcium sulphoaluminate particles, plays a certain coating role, and can effectively reduce the amount of resin and improve the coating efficiency. During the construction process, after the material contacts with water, the resin wrapped on the surface of calcium sulphoaluminate interacts with water to form an intertwined coating film, which can slow release and control the hydration of calcium sulphoaluminate, adjust the formation speed and amount of needle like hydrated calcium sulphoaluminate and hydrated aluminate, effectively delay the setting time of sealing material, facilitate the construction, and endow the sealing material with continuous micro expansion in the sealing process. It provides high early strength for the material and compensates the hydration shrinkage of silicate phase, so that the sealing material can be used continuously and endurably.