40results about How to "Reduce the amount of nitrogen" patented technology

The invention discloses a method for controlling nitrogen content in steel by semi-steel smelting. According to the invention, the method for controlling nitrogen content in steel by semi-steel smelting comprises the following steps of: performing oxygen top blowing by using a converter, performing slag-modifying treatment before tapping, and blocking the slag and tapping. In addition, according to the requirements steel on nitrogen content, different bottom-blowing modes are adopted in the oxygen top blowing process by converter, a foaming agent is added at the last stage of blowing, argon gas is blown to ladles 1 to 3 minutes before tapping, and the soft argon blowing operation is performed on ladles during the tapping step. By adoption of the method provided by the invention, the nitrogen content in steel at the converter end-point can be controlled to be within 11 ppm and the nitrogen increase can be controlled to be between 1ppm to 3 ppm during the tapping step. The method provided by the invention can effectively reduce the nitrogen content at the converter end-point and the nitrogen increase in the tapping step, thereby providing a technical support for the production of low-nitrogen steel and ultra-low nitrogen steel.

The invention relates to field of preparing calcium carbide with oxygen jetting in tower furnace. The calcium carbonate is heat decomposed into calcium oxide and reduced to calcium carbide by carbon material by jetting with preheating oxygen or oxygen-enriched air. The device comprises: tower furnace and systems of feeding, charging, oxygen producing, heating air, blasting air, oxygen enriching, jetting, cooling, cleaning and recoverying coal gas and recovering calcium carbide and ferrosilicon. The ration between said furnace height and furnace hearth diameter is less than or equal to 3.5, and diameter ratio between furnace hearth and furnace hearth is 0.8-1.1. The invention is to produce calcium carbide of 80%, the proportioning of raw material is lime carbonate: coke: fluorite =(1.2-2.0): (1.5-4.0): (0.039-0.046); jetting material is coal powder, light oil or natural gas; relative oxygen-enriched air amount, the xygen-enriched rate is 9-39%, and prepares side products of calcium carbide of more than 65%, ferrosilicon more than or equal to 54% and carbon monoxide of more than or equal to 54% at high temperature. The invention is characterized by energy saving, high quality and environmental protection.

The invention belongs to the technical field of metallurgy, and particularly relates to a method for conducting deoxidization and nitrogen control on output steel of a semisteel steelmaking converter. The method includes the steps that when the oxygen activity of molten steel at the end point is larger than or equal to 800 ppm and steel is output by one fourth to one third, carburant is adopted for preliminary deoxidization; after steel is output by one third, silicon iron is adopted for deoxidization; after steel is completely output, an aluminum wire is adopted for thorough deoxidization on a blowing-argon-behind-converter platform; when the oxygen activity of molten steel at the end point is larger than or equal to 500 ppm and smaller than 800 ppm and after steel is output by one third, carburant is adopted for preliminary deoxidization; it is ensured that the oxygen activity of molten steel is larger than 500 ppm after steel is output, and the aluminum wire is adopted for thorough deoxidization on the blowing-argon-behind-converter platform after steel is completely output. By means of the process, the deoxidizing material consumption can be effectively lowered, production cost is reduced, and resources are saved; meanwhile, the nitrogen increase volume in the steel output process can be reduced, the nitrogen increase can be stably controlled within 5 ppm, and steel performance is ensured.

The invention relates to a method for obtaining low-nitrogen steel by reducing nitrogen content in steel in an electric furnace steelmaking process. The method comprises the following steps that in the smelting process of an electric arc furnace, a mode of mixed smelting of waste steel and molten iron is adopted, a rapid slagging technology is assisted, and silicon iron is added in the tapping process to carry out weak deoxidation on molten steel; in the LF refining procedure, a high-temperature-resistant material sealing sleeve is installed at an electrode opening, refining synthetic slag is added in the smelting process for slagging, and the appropriate bottom blowing argon flow is adjusted; in the VD vacuum treatment process, a high vacuum degree, treatment time prolonging and bottom blowing argon flow increasing strong stirring mode is adopted; and in the continuous casting process, protective pouring and immersion type sleeve sealing measures are adopted. According to the method, the nitrogen content in the steel is obviously reduced on the basis of molten steel nitrogen absorption and denitrification mechanisms and in combination with the operation characteristics of all the procedures, the method is easy to operate, nitrogen control of the whole process in the electric furnace steelmaking process is stable, and it can be effectively guaranteed that the nitrogen content in a finally obtained product is smaller than 30ppm.

The invention discloses a pyrolysis and gasification garbage incinerator adopting an oxygen enriched combustion technique. The pyrolysis and gasification garbage incinerator comprises an oxygen preparation unit, an oxygen injection unit and an incinerator main body unit, wherein the oxygen injection unit is connected with the oxygen preparation unit and the incinerator main body unit, the oxygen injection unit comprises a booster fan, a shutoff valve and two oxygen flow control devices, and each oxygen flow control device comprises a flow meter, a regulating valve, a stop valve, a mixer and an air supply fan; the shutoff valve is connected with the flow meters; the incinerator main body unit comprises an incinerator body and a smoke purification device, and the incinerator body comprises a first combustion chamber, a second combustion chamber and a partition. According to the pyrolysis and gasification garbage incinerator, the problems of low combustion temperature and combustion efficiency, substandard pollutant discharge and the like caused by low oxygen content of air or low garbage calorific value can be effectively solved.

The invention discloses a method for preventing nitrogen increment of LF refined low-nitrogen steel. The method comprises the following steps: allowing molten steel tapped from a converter to enter a station, and carrying out argon stirring under an argon flow of 30-60Nm/l; sequentially adding fluorite, submerged arc slag, small-grain ash, calcium carbide and a deoxidizer in the LF refining process; and selecting a high-grade heavy-current heating mode of the above LF furnace. The method avoids exposure of the molten steel through controlling the argon flow amount without changing present devices or refractory, shortens the existence time of high temperature slag through controlling the heating grade and the current value, avoids slag agglomeration induced long-time heating and stirring through controlling the charging sequence, and reduces the nitrogen absorption of the molten steel in a low oxygen state through controlling the deoxidation moment in order to reduce the nitrogen increment of the molten steel in the refining process. The method has the characteristics of production of low-carbon steel through fully utilizing present conditions of refining without vacuum treatment, easy realization and low production cost.

The invention belongs to the technical field of metallurgy, and particularly relates to an output steel deoxidizing process under the semisteel catching carbon practice condition. The process includes the steps that when the percentage mass content of carbon in molten steel at the end point of a converter is larger than or equal to 0.10% and smaller than 0.20%, carburant is added for preliminary deoxidization when steel is output by one third; a deoxidizing agent is added for thorough deoxidization on a blowing-argon-behind-converter platform after steel is completely output; when the percentage mass content of carbon in molten steel at the end point of the converter is larger than or equal to 0.20%, the output steel is not deoxidized, the deoxidizing agent is directly added for oxygen determination on the blowing-argon-behind-converter platform, the deoxidizing agent is added according to the oxygen determination value, and argon is blown to ladle bottoms when and after steel is output. By means of the process, deoxidization material consumption can be lowered, production cost can be reduced, and meanwhile the nitrogen increase volume in the steel output process can be reduced.

The invention relates to an adjustable oxygenation energy-saving combustion-supporting system. The adjustable oxygenation energy-saving combustion-supporting system is characterized by comprising an air compression unit, an air purification unit, an oxygen-nitrogen separation unit, an oxygenation adjusting mixer unit and an oxygenation applying nozzle unit. The invention provides an adjustable oxygenation energy-saving combustion-supporting system to change the manner of combustion support of air and save the fuel through a stable system in lower cost under the condition that the yield and the quality of the product are unchanged and even improved; meanwhile, the requirements of environmental protection are better met. According to the primary condition of energy conservation measure, the furnace age, the operation habit and the management condition of the primary furnace, after the adjustable oxygenation energy-saving combustion-supporting system is adopted, the energy-saving effects of various industrial furnaces are as follows: 5%-20% for various fuel coal industrial furnaces, 6%-30% for various fuel oil industrial furnaces, and3%-18% for various fuel coal industrial furnaces.

A low-nitrogen carburant powder-deoxidizing alloy powder cored wire for recarburizing and deoxidizing molten steel is composed of a core prepared from the mixture of low-nitrogen carburant powder and deoxidizing alloy powder, and a shell made of high-quality steel sheet (or band). It is applied by inserting it through molten slag layer into molten steel.

The invention discloses a long nozzle and a continuous casting method. The long nozzle comprises a durable material (1) and a steel sleeve (2) arranged outside the durable material in a sleeving way, wherein a hollow part (3) is arranged in the durable material; the durable material is sequentially provided with a gas inlet (4), an annular gas chamber (5) and a vent groove (6), which are communicated with one another, in the thickness direction; the vent groove extends in the thickness direction of the durable material to be communicated with the hollow part; a plurality of gas gaps are formed between the upper surface of the durable material and the steel sleeve, and are communicated with the top of the hollow part and the gas inlet respectively. According to the long nozzle, a double-sealing mode is adopted, a lower nozzle of a large ladle is primarily sealed through the gas inlet, the annular gas chamber and the vent groove by gas, and meanwhile, the combination part of the long nozzle and the lower nozzle of the large ladle can be secondarily sealed through the gas gaps formed by a plurality of bumps which are distributed on the upper surface of the durable material at intervals by the gas, so that double sealing effects are achieved, the sealing performance is high, the nitrogen increase of molten steel from the large ladle to a medium ladle can be effectively reduced, and the nitrogen increase of the molten steel in a continuous casting process can be controlled within 3ppm.

The invention discloses a liquid steel nitrogen adding device for controlling steel tapping procedures. The liquid steel nitrogen adding device comprises a cylindrical argon plug, electric stop valves and electric flow regulating valves. The cylindrical argon plug sleeves a steel tapping opening, two argon plug rings are uniformly distributed at the lower end of the cylindrical argon plug, and a plurality of argon holes are formed in the two argon plug rings in a staggered manner; a plurality of argon pipelines which are communicated with the argon holes are uniformly arranged in the cylindrical argon plug in a staggered manner; argon metal hoses are externally connected with the argon pipelines and are connected with argon sources, the electric stop valves and the electric flow regulating valves respectively. A method for controlling the steel tapping procedures includes enabling pipeline argon to flow before the steel tapping procedures are carried out; enabling argon in the inner ring and the outer ring to flow at first to form two cone argon layers when the steel tapping procedures are carried out; adjusting the electric flow regulating valves to control the flow of the argon; shutting the electric stop valves when the steel tapping procedures are terminated. The liquid steel nitrogen adding device and the method have the advantages that liquid steel and steel drop are enclosed by two argon cones, accordingly, liquid steel nitrogen adding effects for controlling the steel tapping procedures can be realized, the liquid steel nitrogen adding device is simple in structure and low in manufacturing cost, the method is easy to implement, and obvious effects can be realized.

The invention relates to the field of methods or equipment specially suitable for incineration of waste or low-grade fuel, in particular to a garbage incineration device in an oxygen-enriched atmosphere and a using method thereof. The garbage incineration device in the oxygen-enriched atmosphere comprises an incinerator (1), and is characterized in that the garbage incineration device further comprises a dust remover (2), a heat exchange device (3), a combustion-supporting fan (4), a purifier (5) and an oxygen generator (6), a flue gas outlet of the incinerator (1) is connected with an inlet of a flue gas pipeline of the heat exchange device (3) through the dust remover (2), an outlet of the flue gas pipeline of the heat exchange device (3) is connected with the purifier (5), and an oxygenoutlet of the oxygen generator (6) is connected with a flue gas delivering pipe (71) through an oxygen delivering pipe (72). The using method of the garbage incineration device in the oxygen-enrichedatmosphere is characterized in that the method is implemented according to the following steps of a, material preparing, b, incineration, c, heat exchanging, and d, flue gas exhausting sequentially.According to the garbage incineration device in the oxygen-enriched atmosphere and the using method thereof, full combustion is achieved, complete degradation is achieved, and adaptability is high.

The invention discloses a hazardous waste incineration process and system. The hazardous waste incineration process comprises the following steps that S1, compatibility is conducted, specifically, hazardous waste is mixed and compatible and conveyed into a first incineration area; S2, incineration is conducted, specifically, the mixed materials obtained after compatibility are subjected to a primary combustion reaction in a first incineration area, and primary flue gas is obtained; the primary flue gas is conveyed into a second incineration area to be subjected to a secondary combustion reaction, and secondary flue gas is obtained; S3, flue gas treatment is carried out, specifically, the secondary flue gas is cooled and purified and then discharged; in the primary combustion reaction process, used combustion-supporting gas I contains 45%-55% of oxygen; and in the secondary combustion reaction process, used combustion-supporting gas II contains 75-85% of oxygen. According to the processand system, the investment and operation cost is low, and the treatment effect is good.

The invention discloses a method for reducing an increased nitrogen amount of high-strength steel in a converter ladle. The method comprises the steps of: controlling the acid-soluble aluminum of themolten steel in the ladle to 50-200 ppm; controlling the temperature of the molten steel entering the ladle to be 1585+/-10 DEG C; alloying manganese with medium carbon ferromanganese and electrolyticmanganese. The method reduces the nitrogen content of the high-strength steel product by controlling the acid molten aluminum content of the ladle, the temperature of the ladle and the use amount ofalloy used for replacing or reducing the high nitrogen content, and the quality of the steel is improved while the increased nitrogen amount of the molten steel in the ladle of the converter process is suppressed. The method can effectively reduce the increased nitrogen amount of the molten steel in the ladle of the high-strength steel of the converter process, from the original 15+/-3ppm to 5+/-2ppm, thereby improving the quality and performance of the finished steel.

The invention discloses an ultralow-nitrogen ultralow-boron molten steel refining agent and a preparing method. The refining agent is composed of a component C and a component D, the component C is low-boron active lime, the component D is single one or any combination of industrial aluminum ash, bauxite or calcium slag, the refining agent is alkalinityR:3.0-5.0(CaO/SiO2), N is smaller than or equal to 0.02%, and B is smaller than or equal to 0.001%. The advanced premelting vacuum refining process is adopted in the molten steel refining agent, the component is uniform, checking is convenient,and mechanical and manual charging is facilitated. The refining agent is free of dust, use is safe and environment-friendly, the content of harmful elements N and B is extremely low, storage and transportation are facilitated, at the high temperature, during use, the agent is not prone to oxidation by air, the yield is high, deoxidization efficiency in the slag is high, the speed is high, and therefining agent is the most ideal high-cleanliness molten steel refining agent.

The invention discloses a method for controlling the nitrogen content of a niobium-containing steel type. The method is characterized in that argon is blown into an empty steel ladle before tapping ofa converter, so that molten steel flow and the molten steel surface in the tapping process are always in the argon atmosphere; and the molten steel is isolated from air by the argon, so that absorption of the molten steel to nitrogen in air is reduced, and the content of the nitrogen in the molten steel is effectively controlled. Compared with the prior art, the method for controlling the nitrogen content of the niobium-containing steel type has the beneficial effects that the nitrogen increasing amount of the niobium-containing steel type in the converter tapping process is greatly reduced,pressure for treating the molten steel is relieved for the subsequent refining process, the nitrogen content in the molten steel is prevented from exceeding the standard, the corner crack of a continuous casting blank is reduced, the offline corner cleaning cost of the continuous casting blank is reduced, and the heat charging rate of the continuous casting blank is improved.