Coating granule magnesium desulfurizer and preparation method thereof

Abstract

The invention discloses coating solid magnesium desulfurizer and a manufacture method thereof; the coating solid magnesium desulfurizer is made of following components in weight percentage: (1) 94 to97 percent of metal solid magnesium, 1 to 4 percent of magnesia powder, 0.1 to 1.0 percent of graphite powder, 0.5 to 1.5 percent of chloride, 0.1 to 0.5 percentof selenious acid and 0.2 to 0.6 percent of silicone grease; (2) components producing process is as follows: raw material - mix - agitation - response - adding package agent - dry -screen separation - finished product; earthy graphite powder, magnesia, chlorine salt, selenious acid and silicone grease are adopted as the composition and such producing technical solution is adopted as from raw material - mix - agitation - response - adding package agent - dry - screen separation - finished product. The method overcomes such flaws exiting in the prior coating solid magnesium desulfurizer as surface hygroscopicity and agglomeration ofthe solid magnesium, inconvenience for transportation and storage, lance sticking, jammed and splattering in the process of spraying and blowing, a plurality of used cerium oxide, expensive price, badeffect of formaldehyde on human heath and environment pollution, etc. The coating solid magnesium desulfurizer and the manufacture method are widely applied in molten iron pre-desulphurization and molten steel deepening desulphurization production in steel and iron smelting industry.

Description

technical field [0001] The invention relates to a coating granular magnesium desulfurizer used for pre-desulfurization of molten iron and deep desulfurization of molten steel in the iron and steel smelting industry and a preparation method thereof, in particular to a magnesium desulfurizer containing earthy graphite powder, magnesium oxide, chloride salt, selenous acid and Composite coating granular magnesium desulfurizer of silicone grease series and preparation method thereof. Background technique [0002] The development of modern industry has put forward higher requirements for the iron and steel industry. How to minimize the sulfur content in steel has become one of the first-choice tasks in the steelmaking process, especially for value-added steels that require high strength and toughness. production of various types (such as IF steel, high-grade pipeline steel, etc.). [0003] Magnesium is a very light metal with an atomic number of 12, an atomic weight of 24.305, an...

AI Technical Summary

Problems solved by technology

[0004] In the existing published patent documents, as the Chinese Patent Publication No. CN1459510 "a kind of manufacturing method of molten iron desulfurizer-coated granular magnesium" discloses that various chloride salts (sodium chloride, magnesium chloride, potassium chloride, chlorine Calcium chloride, barium chloride) are mixed in a certain proportion and dissolved in 100°C water to form a liquid chloride salt, and then placed in a rotary kettle with raw materials at a temperature of 210°C-240°C, and the liquid chloride salt is sprayed while rotating The technical scheme of drying the product on the surface of raw material magnesium grains at high temperature. In this technical scheme, chloride salt covers the surface of magnesium grains, which is easy to absorb moisture, and even agglomerates in serious cases. Not only is it not conducive to the storage of the product, but also During the injection process, it is easy to cause gun blockage, splashing, etc.

Another example is that the Chinese Patent Publication No. CN1962889 "passivated magnesium desulfurizer containing rare earth oxides and its preparation method" discloses that first metal magnesium particles are dry-mixed with cerium oxide and magnesium oxide powder, and then acetic acid, magnesium chloride and Mix water to make a passivation solution, then pour the passivation solution into the metal magnesium of the mixed cerium oxide and magnesium oxide powder, stir until the material is dry, and naturally cool to prepare a passivated magnesium desulfurizer containing rare earth oxides , the cerium oxide in the disclosed passivated magnesium desulfurizer is a kind of rare earth oxide, and the market price is expensive (about ¥25,000-¥30,000 per ton). In the process of preparing the desulfurizer, the amount of cerium oxide is large, and the production The cost is extremely high; moreover, the acetic acid in this invention has strong corrosiveness, and its aqueous solution is acidic, and it is easy to react with metal magnesium, which will reduce the magnesium content and reduce the desulfurization rate

For another example, Chinese Patent Publication No. is CN1647873 " a kind of passivation magnesium powder " disclosed is the passivation magnesium powder that is used for steelmaking desulfurization to add flame retardant and bonding agent to make in granular magnesium powder, Its flame retardant is glass water, magnesium hydroxide, fossil powder, dolomite or its mixture, and binding agent is 107 glue, but the passivated magnesium powder surface coating that this invention prepares comes off easily, is unfavorable for the transportation and transportation of magnesium. Storage, and it is easy to cause splashing during the desulfurization process. The 107 glue used contains formaldehyde, which is harmful to human health, and seriously pollutes the environment.

In addition, the Chinese Patent Publication No. CN1311070 "Composite Coating Magnesium Particles and Preparation Method thereof" discloses that a layer of hydrophobic agent is first coated on the surface of the metal magnesium particles, and then a layer of flame retardant is coated on the surface of the hydrophobic agent. The hydrophobic layer is one or both of rosin, silicone oil, and lithium hydroxide, and the flame-retardant layer is calcium oxide, magnesium oxide, aluminum oxide, phosphorus pentoxide, silicon dioxide, and mixtures thereof. The material of the above-mentioned hydrophobic layer will have a side effect on the molten iron, so that more slag will be produced during the desulfurization process, thereby increasing the iron loss caused by slag removal, and the surface coating of granular magnesium produced by this method is extremely difficult during transportation. Easy to fall off, easy to cause gun sticking or even blockage during desulfurization