36results about How to "Meet smelting requirements" patented technology

The invention discloses a multi-layer composite runner brick and a production method thereof. The multi-layer composite runner brick comprises a brick base body, wherein the brick base body is provided with a steel liquid flow passage; a combining layer and a working layer are sequentially compounded onto the surface of the steel liquid flow passage; the brick base body is prepared from main materials including flint clay, pyrophyllite, third-level alumina clinker and clay, and a small amount of added sillimanite, andalusite and potassium feldspar; the working layer is prepared from main materials including corundum, mullite and alpha-Al2O3 micropowder, and a small amount of added sillimanite, silicon micropowder, clay and andalusite; the raw materials of the working layer are compounded into slurry, the slurry is sprayed onto the surface of the steel liquid flow passage and is fired, and the working layer reacts with a base body layer to form a mullite-based combining layer, thereby forming a whole; in a steel casting process, the working layer, the combining layer and the base body layer are closely combined together, so as to avoid the separation of the working layer. The multi-layer composite runner brick has the advantages that the cost is low, the high-temperature property is good, the anti-scouring erosion capability is strong, the market competition advantage is obvious, the thickness of the working layer can be adjusted through design, and the multi-layer composite runner brick is suitable for smelting different types of special steel.

The invention discloses a machine pressing carbon-free lining brick for steel ladles, which comprises the following components (according to weight percentage): 20-24% of brown aluminium oxide particle, 28-30% of first white alundum particle, 12-16% of second white alundum particle, 15-20% of white alundum powder, 10-12% of alumina micro powder, and 3-6% of efficient binding agent, wherein the diameter of the brown aluminium oxide particle is 3-5 mm, the diameter of the first white alundum particle is 3-5 mm, and the diameter of the second white alundum particle is 0-1 mm. The invention has the benefits that (1) the machine pressing carbon-free lining brick is free from carbon, and in the steel smelting process, carbon in steel is not increased, so that the smelting requirements of low-carbon steel and ultra-low carbon steel are met; (2) an effective binding agent (aluminum sulfate) is adopted as an inorganic binding agent, has higher thermal state strength, and can ensure that the thermal state strength is higher within the range from normal temperature to high temperature, and the low smelting phase is not generated; and (3) compared with a conventional fireproof material, the machine pressing carbon-free lining brick has the characteristics of high density, high compression strength and long service life.

The invention discloses a preparation process of a low-grade laterite nickel ore oxidized pellet. The preparation method comprises the following steps: drying low-grade laterite nickel ore until the moisture content of the laterite nickel ore is 11-13%, and crushing the laterite nickel ore with a double-roll crushing mill until the grain size of the laterite nickel ore is minus 3mm; evenly mixinglaterite nickel ore, iron ore concentrate, chromite and a calcium-containing additive in a mass proportion of (45-50%):(30-35%):15%:(5.0-7.7%); carrying out high-pressure rolling pretreatment on the mixed material; pelletizing on a disk pelletizing machine, wherein the moisture content of fresh pellet is 12-12.5%, and the grain size of the fresh pellet is controlled to 12-16mm; and carrying out drying preheating and roasting on the fresh pellet in a chain gate and a rotary kiln or a belt type roasting machine so as to obtain the finished product oxidized pellet, wherein the preheating temperature is 1000-1100 DEG C, the preheating time is 12-15 minutes, the roasting temperature is 1220-1280 DEG C, and the roasting time is 12-15 minutes. The invention relates to the preparation process of the low-grade laterite nickel ore oxidized pellet with high finished product pellet compression strength and wide roasting temperature range when the laterite nickel ore is used for production of pellets.

The invention provides a method for the dephosphorization of phosphorized crude-nickel iron by refining; a dephosphorization agent of lime or limestone with 3 to 8 percent of the quality of the crude-nickel iron and flux fluorite with 0.5 to 3 percent of quality of the crude-nickel iron are added in the melt high sulfur crude-nickel iron in a middle-frequency induction furnace; under a high temperature, the dephosphorization agent and the flux are melt; the industrial oxygen or high pressure air with a pressure of 0.3 to 0.7MPa is blown into the flux in the furnace; top blowing and refining are carried out for 3 to 15 minutes under the condition of a temperature of 15000 to 1600 DEG C to lead the carbon thereof to be oxidized and carry out slagging after partial iron is led to be oxidizedwith the impurities like silicon and phosphor; after the refining is finished, the slag is removed to obtain the refined nickel iron; wherein, the phosphor, the carbon and the silicon are reduced to be below 0.015 percent; the quality of the nickel is improved to be above 15 percent; the direct yield of nickel is equal to or more than 95 percent. The method of the invention has a simple techniqueand low energy consumption; besides, the method of the invention is easy to realize industrial production.

The invention discloses a preparation method for vanadium-titanium-iron concentrate magnetized pellets for a shaft furnace. The method comprises the steps: a, mixing of raw materials: mixing uniformly a vanadium-titanium-iron concentrate powder and a binder according to the following weight ratio: wherein the weight ratio of the vanadium-titanium-iron concentrate powder to the binder is 100: 2-6; b, pelletizing: pelletizing the uniformly mixed material to obtain green pellets; c, drying: drying the green pellets; d, magnetization roasting: carrying out magnetization roasting of the dried green pellets at the temperature of 1000 DEG C-1200 DEG C to obtain magnetized pellets; and e, protective cooling: carrying out protective cooling of the magnetized pellets or carrying out hot delivery and hot charging into the gas-based shaft furnace for direct reduction. The preparation method has simple process steps, requires a few devices, and can meet needs of industrial production. The pellets obtained by the method can effectively eliminate catastrophic expansion of vanadium-titanium-iron concentrate pellets, play roles of restraining pulverization and bonding and improving desulfurization effect, and meet smelting requirements of the shaft furnace and a blast furnace.