987results about "Shaft furnace" patented technology

A process and system for producing reducing gases are disclosed, wherein volatile components derived from coal are transformed into reducing gases suitable for utilization as synthesis gas, as a reducing agent for the direct reduction of iron ores and / or as a clean fuel.

A process for energy- and emission-optimized iron production and an installation for carrying out the process. A first partial amount of a generator gas produced in a melter gasifier is used as a first reducing gas in a first reduction zone. A second partial amount is fed to at least one further reduction zone as a second reducing gas. In addition, after CO2 scrubbing, a partial amount of top gas removed from the first reduction zone is admixed with the generator gas after the latter leaves the melter gasifier, for cooling the generator gas.

A cooling system comprises serpentine cooling fluid passages cast into a work piece with carefully controlled turning radii and profiles. Individual interdigitated baffles are contoured in the plane of coolant flow to have walls that thicken and then round off at their distal ends. The outside radii at these turns is similarly rounded and controlled such that the coolant flow will not be swirled into eddies.

The invention discloses a method and device for producing direct reduced iron by using a gas-based reduction shaft furnace. Coal reducing gas and coke oven gas are mixed and supplied to a shaft furnace so as to produce direct reduced iron. The method comprises the following steps: separating the coke oven gas into hydrogen gas and linde gas, mixing the hydrogen gas with the coal reducing gas and using as reducing gas to reduce iron ores, and using the linde gas as cooling gas to cool direct reduced iron. The device for realizing the method comprises a shaft furnace, a coke oven gas source, a coal gasification device, a coke oven gas hydrogen-extracting device and a gas heating device. In the invention, coal gasification devices of different sizes can be flexibly used with a coke oven gas supply device, thereby reducing the size of the coal gasification device and effectively using the coke oven gas. Meanwhile, the invention cancels the minor cycle of a cooling section of a common shaft furnace, saves the equipment and investment, and brings the heat of direct reduced iron to a reducing section, thereby saving the heating load of the system reducing gas.

A method and apparatus for simultaneously supplying varying proportions of hot and cold direct reduced iron(DRI) material from a source of hot DRI for melting, storage, briquetting, or transport. The system uses gravity to transport hot DRI material from a reduction furnace to a furnace discharge section, which transports desired amounts to a cooling receptacle and to a hot DRI vessel. The cooling section of the apparatus is connected to the furnace discharge section through a dynamic seal leg. The hot section is also connected to the furnace discharge section through separate a dynamic sealing leg and can feed a surge vessel, a briquetter, a storage vessel or a melting furnace. The method of operation is also disclosed.

The invention relates to a preparation process and a device of sponge iron, belonging to metallurgical industry steel-making raw material. The process comprises the following steps: mixing iron-containing raw materials with reducing agent, solvent and catalyst to prepare ultra fine powder, passivating and mixing to make pelletizing materials, sending the prepared pelletizing materials into a reducing furnace, drying and roasting, and obtaining sponge iron after the reduction reaction. The reducing device is connected with an upper furnace above a furnace base, a lower furnace body is connected to the downside of the furnace base, the upper end of the upper furnace body is connected with an upper furnace mantle, a drying bed grate is positioned at the upper end in the upper furnace body, a purifying device is connected with the upper furnace body and the lower furnace body through pipelines, and a residual heat circulating device is connected with the lower furnace body. The invention has the advantages that: firstly, the reduction temperature is reduced, the reduction speed is increased, the energy consumption is reduced, the production cost is lowered, the production efficiency is improved, and the uniformity of the quality is ensured; secondly, the degree of mechanization is high, the procedure is simple, the yield is large, the mass production can be performed; thirdly, the waste of raw materials is lowered, the environment pollution is reduced; and fourthly, the waste resource can be recycled so as to save the resource consumption.

The invention discloses a coal-derived reducing gas base shaft furnace direct reduction metallurgical method and a system thereof. Reducing gases with CO and H2 serving as the main components are prepared from coal through a coal-derived reducing gas system, and are treated by the reducing reaction with iron ore through a direct reduction metallurgical system. The reducing gases are mainly used as the reducing agents of the reducing flow, the cooling agents of the cooling flow and the fuel of the direct reducing metallurgical system. The reducing flow is composed of a reducing shaft furnace, a furnace top gas heat exchanger, a furnace top gas shock chilling / scrubbing system, a process gas recycle compressor, a compressor secondary cooler, a CO2 absorber, a process gas humidifier, a process gas heater, etc. The conical part of the lower part of the shaft furnace is the cooling zone of the shaft furnace direct reduction metallurgical furnace. The cooling gases are sprayed in from the conical region of the lower part of the shaft furnace direct reduction metallurgical furnace, and flow upwards across the metallurgical furnace. The hot cooling gases flow away the cooling region and then are cooled, compressed and recycled. The system is simple in structure and low in process cost.

The invention provides a method for pulverized coal gasification for gas generation and direct reduction metallurgy of a gas-based shaft furnace. According to the method, feed coal is ground and then enters a gasification furnace in a form of pulverized coal; the pulverized coal reacts with a gasification agent oxygen and water vapor to generate crude gas rich in CO and H2; the high-temperature raw gas generated by the gasification furnace is subjected to cooling and wet cleaning for dust removal to obtain crude synthesis gas mainly containing CO and H2; the crude synthesis gas is adjusted into a reducing agent for a gas-based shaft furnace through water vapor conversion and purification; and the reducing agent enters the shaft furnace and reacts with lump ores or pellets to generate reducing iron. Through the invention, the coal gasification is combined with a gas-based direct reduction shaft furnace technology, thus the limitation on total natural gas of a gas-based direct reducing method is overcome, and large-scale production is realized; and the method has the advantages of low energy consumption, little pollution and the like.

The invention relates to a process and a device for smelting chromium irons and chromium-containing molten iron by using chromium ore powder, which belongs to metallurgical industry steel-making raw material. The process comprises the following steps: mixing chromium iron containing raw materials with reducing agent, solvent and catalyst to prepare ultra fine powder, mixing to make pelletizing materials, sending the pelletizing materials into a reducing furnace, obtaining chromium irons pellets after the reduction reaction, and directly adding reduced pellets into a lining electroslag furnace for being smelted into the chromium-iron alloy or the chromium-containing molten iron. The device comprises an internal-external heating vertical reducing furnace, a lining electroslag furnace and a residual heat recovery system. The invention has the advantages that: firstly, the reduction temperature is low, the speed is high, the energy consumption is reduced, the production cost is lowered, the production efficiency is high, and the uniformity of the quality is good; secondly, the degree of mechanization is high, the procedure is simple, the yield is large, the mass production can be performed; thirdly, the waste of raw materials is reduced, the environment pollution is lowered; fourthly, the source of raw materials adopting the chromium ore powder and chromium-containing waste, the cost is low; fifthly, the waste resource can be recycled so as to save the resource consumption; and sixthly, the high-temperature pellets are directly smelted by adopting the lining electroslag furnace, the heat efficiency is high, the energy consumption is low, the material purity is high and the quality is good, and the device is simple with less investment.

In the method of producing reduced iron according to the invention, fine iron oxides and powdery solid reductants are mixed, compacted into sheet-like compacts, and charged onto the hearth of a reduction furnace for reduction while maintaining the temperature inside the furnace at not less than 1100 DEG C. As the sheet-like compacts can be obtained by compacting mixture of raw material by use of rollers or the like, processing time is much shorter than the case of pelletization or agglomeration. A drying step is unnecessary since feeds are placed no the hearth via a feeder chute or the like. The method is carried out with ease by use of the facility according to the invention. High quality hot metal can be produced by charging reduced iron in hot condition obtained by the method described as above into a shaft furnace or a in-bath smelting furnace for melting at high thermal efficiency.

A process for reducing iron ore particles in a moving bed reduction reactor comprising an upper reduction zone and a lower discharge zone, wherein the coke oven gas, preferably forming all the make-up for the reducing gas circulating through and reacting in said reduction zone, is first fed to said discharge (cooling) zone and thereafter said coke oven gas, conditioned by the DRI in the lower zone, is withdrawn from the reactor and fed preferably into the recycled reducing gas for injection into the reduction zone of the reactor. Heavy hydrocarbons and other components of coke oven gas which may otherwise cause fouling, corrosion, or deposits in the direct reduction plant are removed from coke oven gas by catalytic and / or adsorptive action of the DRI present in said lower zone, before being externally transferred to the reduction zone of the reduction reactor.

The invention discloses a method for comprehensively using vanadium-titanium magnetite by shaft furnace reduction and electric furnace melting, characterized by: mixing vanadium-titanium magnetite concentrates with a binder to prepare oxidized pellets, reducing in a gas base shaft furnace at 900-1200 DEG C under the pressure of 0.2-0.3Mpa for 4-6 h, wherein the content of the reducing gas that is a mixture of H2 and CO is no less than 90%, and the molar ratio of H2 to CO is 1-3; putting the reduction product into the electric furnace for melting and conducting slag-iron separation to obtain molten iron and slag, wherein the slag contains vanadium-titanium and is used for vanadium extraction and titanium extraction. According to the invention, effectively extraction and utilization of titanium can be realized; there is no need for coke and no coking coal is consumed, thus the increasing insufficiency of coking coal resource is alleviated.

The invention relates to a method to make low carbon sponge iron by microwave shaft furnace. It adopts iron ore powder as raw material, common soft coal dust or anthracite dust as reducer to gain high quality low carbon sponge. It uses the feature that the iron ore powder, carbon powder, and lime powder has selective absorbing to microwave. Under the condition of sealing and high temperature, and under the effect of microwave generator, heater, and adjustor, it would take carbon heat self-reduction by absorbing the heat produced by microwave generator to gain low carbon sponge iron. The method has simple technology, shortens the reduction time period, saves coking coal and coke resource, and reduces environment pollution. The degree of metallization could reach 90-98%, and the carbon content could be lower than 0.5%. It is the ideal method to make low carbon sponge iron.

A loading device for a shaft furnace comprises a chute supported by a suspension rotor (28) in a fixed housing. The rotor (28) is fitted with a cooling circuit, supplied with liquid coolant via a rotating annular joint (44). The latter comprises a fixed ring (60) and a rotating ring (62), and is fitted in an annular leak collecting tank (46) formed by the suspension rotor (28). Fixed ring (60) is supported by the housing (12). Rotating ring (62) is supported entirely by fixed ring (60) via a bearing (64). Selective coupling means (65, 66) connect the rotating ring (62) to the suspension rotor (28) in such a way as to transmit a rotary moment of rotor (28) to rotating ring (62) selectively, while at the same time preventing other forces from rotor (28) being transmitted to rotating ring (62).

In the method of producing reduced iron according to the invention, fine iron oxides and powdery solid reductants are mixed, compacted into sheet-like compacts, and charged onto the hearth of a reduction furnace for reduction while maintaining the temperature inside the furnace at not less than 1100° C. As the sheet-like compacts can be obtained by compacting mixture of raw material by use of rollers or the like, processing time is much shorter than the case of pelletization or agglomeration. A drying step is unnecessary since feeds are placed no the hearth via a feeder chute or the like. The method is carried out with ease by use of the facility according to the invention. High quality hot metal can be produced by charging reduced iron in hot condition obtained by the method described as above into a shaft furnace or a in-bath smelting furnace for melting at high thermal efficiency.

The invention discloses a method for preventing pellets from high temperature reduction bonding in a high phosphorus oolitic hematite treatment shaft furnace, belonging to the technical field of direct-reduction ironmaking. High phosphorus oolitic hematite powder, pulverized coal, a dephosphorization agent and a bonding agent are mixed together according to a proper ratio, the mixture is milled and pressed into balls so as to prepare cold bound pellets, and the bound pellets are dried or maintained and are further conveyed into a direct-reduction shaft furnace; in the direct-reduction shaft furnace, the pellets are subjected to hot coal gas roasting, gas-based prereduction, coal-based direct reduction and cooling process from top to bottom, temperature range of gas-based prereduction and coal-based direct reduction for the bound pellets is 850-1200 DEG C, and standing time in the shaft furnace is 1-5 hours; the reduction gas comprises H2 and CO in a ratio of 1.2-4; the reduced pellets are sealed and cooled, at the outlet of a cooling section, temperature of the bound pellets is controlled to be 100-200 DEG C, and the bound pellets are further smashed, magnetically separated and briquetted, wherein TFe in the obtained iron product is not less than 88%, and phosphorus content is less than 0.3%. The method has the advantages of decreasing energy consumption of reduction process of the shaft furnace.

The invention discloses a method for recovering iron, vanadium and titanium from schreyerite through shaft furnace reduction and electric furnace smelting and separating deep reduction. The method comprises the following steps of: producing a vanadium-titanium oxidized pellet; directly reducing the vanadium-titanium oxidized pellet; smelting and separating a metalized pellet through an electric furnace; extracting vanadium from molten vanadium-containing iron; smelting and separating titanium slag to manufacture titanium dioxide; smelting and separating vanadium slag to manufacture V2O5. According to the method, coal gas, converted coke oven gas or natural gas is used as a reducing agent to reduce original vanadium titanium magnetite, so that the dependency of the traditional blast furnace process to coking coal can be greatly reduced, and diversification of metallurgical energy is realized; by adopting the process, the vanadium titanium magnetite can be smelted completely; mixed smelting of common iron ore and vanadium titanium magnetite is not needed, so that the smelting efficiency is higher; titanium dioxide in the smelted and separated titanium slag produced in smelting accounts for more than 50%, therefore, the slag can be directly used as the raw material for preparing titanium dioxide, and as a result, the recovery rate of vanadium, titanium and iron can be raised; simultaneously, the smelted and separated titanium slag and vanadium slag can be directly utilized, thus the environmental pollution and land resource occupation caused by piling and storing the slag can be avoided.

The invention discloses a recycling process of iron-containing zinc powder generated in an iron and steel process. The process comprises the following steps: mixing dried iron-containing zinc powder with a binder, and pelletizing by a pelletizer to obtain green balls; feeding the green balls into a shaft furnace and heating to 1100-1300 DEG C; reducing iron in the shaft furnace to sponge iron; converting reduced zinc at high temperature into zinc steam which is discharged out of the shaft furnace with coal gas and enters into a two-stage dedustor; and feeding dedusting mud obtained from the dedustor into a settling pond, and filtering, settling, thickening and drying to obtain zinc powder. The iron-containing zinc powder mainly comprises blast furnace gas ash, gas mud, dedusting ash, converter steelmaking dust and continuous casting steel rolling scrap iron generated in the iron and steel production. By adopting a treatment mode of the shaft furnace, the problem such as large rotary kiln equipment, low utilization ratio of in-kiln volume and high energy consumption is solved. Coal base is directly reduced at a high speed, and meanwhile, zinc in dust is further recovered.

The invention relates to a smelting process and a device of pure iron, belonging to metallurgical industry steel-making raw material. The process comprises the following steps: mixing iron-containing raw materials with reducing agent, solvent and catalyst to prepare ultra fine powder, mixing to make pelletizing materials, sending the prepared pelletizing materials into a reducing furnace, obtaining metallic pellets after the reduction reaction, and directly adding the reduced pellets into a lining electroslag furnace for being smelted into pure iron. The device comprises an internal-external heating vertical reducing furnace, a lining electroslag furnace and a residual heat recovery system. The invention has the advantages that: firstly, the reduction temperature is low, the speed is high, the energy consumption is reduced, the production cost is lowered, the production efficiency is high, and the uniformity of the quality is good; secondly, the degree of mechanization is high, the procedure is simple, the yield is large, the mass production can be performed; thirdly, the waste of raw materials is reduced, the environment pollution is lowered; fourthly, the source of raw materials adopting iron ore concentrate powder and iron-containing metallurgical waste, the cost is low; fifthly, the waste resource can be recycled so as to save the resource consumption; and sixthly, the high-temperature pellets are directly smelted by adopting the lining electroslag furnace, the heat efficiency is high, the energy consumption is low, the material purity is high and the quality is good, and the device is simple with less investment.

The invention relates to a method for recovering and utilizing kiln slag of a zinc hydrometallurgy volatilizing kiln, comprising the following steps: firstly, crushing the kiln slag into particles with the particle diameter of about 0.01 to 2 mm, and carrying out primary selection under the magnetic field intensity of 800 to 1800 oersteds to obtain a first magnetic part and a first non magnetic part of the kiln slag; and secondly, crushing the first magnetic part into 200 meshes with the particle size range of 50 to 60 percent by weight, and carrying out fine selection with the magnetic fieldintensity of 500 to 1090 oersteds to obtain a second magnetic part and a second non magnetic part. By adopting the method, the recovery rate of metal component or carbon component in the kiln slags isobviously enhanced, the kiln slag is efficiently utilized to the maximum, and the environmental pressure is greatly reduced.

A method of manufacturing reduced iron at high Fe purity efficiently with less intrusion of a slag components using less carbonaceous reducing agent and fuel, comprising charging a compact of the iron oxide containing a carbonaceous reducing agent in a packed bed, reducing the iron oxide to 90% or more while keeping in a solid state by a heat source formed from the lower portion of the furnace and then melting the same, as well as an apparatus for manufacturing the metallic iron, comprising a fire grate disposed in the inside of a packed bed, a compact charged layer on the fire grate, a charging product charging mechanism for supplying the compact and a mechanism for discharging an exhaust gas in the furnace, and a fuel charging mechanism, a fuel combustion space and a molten product stores bath disposed below the fire grate.

A direct reduction process for producing direct reduced iron (DRI) in a reduction reactor having a reduction zone for reducing iron-oxides-containing particles, such as iron ore pellets, to DRI by reaction of said iron oxides with a high temperature reducing gas, and a cooling zone for lowering the temperature of the DRI produced in said reduction zone, wherein a stream of cooling gas, usually natural gas, is circulated through said cooling zone, a portion of said cooling gas is withdrawn from the cooling zone, cooled and cleaned in a gas cooler and a portion of the cooled gas is recycled to said reduction zone by means of an ejector utilizing the high-pressure natural gas make-up feed as the ejector's motive fluid. Using an ejector for recycling the cooling gas instead of using a mechanical compressor provides significant savings in electricity and in capital, operational and maintenance costs. A direct reduction plant having a DRI cooling zone which uses at least one ejector in recycling at least a portion of cooling gas to the cooling zone.

The present invention relates to a process for the direct reduction of iron ore performed by means of a plant comprising a gravitational furnace (2) having at least one iron ore reduction zone (8) in the upper part thereof, and at least one carbon deposition zone (9) and one reduced metal product cooling zone (10) in the lower part thereof, and means for feeding a reducing gas mixture into the reactor in correspondence to the with the reduction zone, means for recycle exhaust or reactor off gas from the reactor to syngas and mixing the recycled gas with natural gas to form a reducing gas mixture. According to the invention a in first reformation step (5) unreacted carbon monoxide CO and steam present in the reactor off gas is reformed to carbon dioxide and hydrogen following the water gas shift reaction CO+H20=CO2+H2, in a secondary reformation step the de-watered reactor off gas comprising mainly of carbon dioxide and hydrogen is processed to remove carbon dioxide, and in a third reformation step physical separation of both nitrogen and carbon oxide CO from the reducing syngas is carried out to bring down the levels of CO and any existing other gases in the recycled gas to as low level as possible such that recycled reducing gas is as close to pure hydrogen H2 as possible.

The invention discloses a high-wind-temperature rotational flow injection disturbance melting reduction and prereduction combination device and a method, which belong to the technical field of melting reduction. The device comprises a raw material system, a furnace top material charging and distributing system, a melting reduction furnace, a furnace top high-temperature gas system, a prereduction furnace, a semicoke gas recycling system, a coal dust preparing and spraying system, a molten iron desulfurizing agent preparing and jetting device, an oxygen and nitrogen supplying system, a residual iron treating system, a high-wind-temperature hot blast furnace, a melting reduction furnace blower, a furnace top gas dedusting and recycling system and a gas cogeneration device. The method comprises the following steps of: introducing high-temperature gas which is generated in a high-wind-temperature rotational flow injection disturbance melting reduction furnace into the prereduction furnace; directly reducing an iron-containing raw material in a solid phase state into a prereduction furnace material with a certain metallization rate; cooling, and then adding the cooled material and semicoke which serve as the furnace material and a fuel respectively into the melting reduction furnace; and finally producing molten iron by reduction. The device and the method have the advantages of high production efficiency and low energy consumption, are easy to operate and make industrialization easily realized.

The invention relates to a process and a device for smelting ferronickel and nickel-containing molten iron by using lower-nickel materials, which belongs to metallurgical industry steel-making raw material. The process comprises the following steps: mixing ferro nickel containing raw materials with reducing agent, solvent and catalyst to prepare ultra fine powder, mixing to make pelletizing materials, sending the pelletizing materials into a reducing furnace, obtaining chromium irons pellets after the reduction reaction, and directly adding reduced pellets into an lining electroslag furnace for being smelted into ferro nickel alloy or the nickel-containing molten iron. The device comprises an internal-external heating vertical reducing furnace, a lining electroslag furnace and a residual heat recovery system. The invention has the advantages that: firstly, the reduction temperature is low, the speed is high, the energy consumption is reduced, the production cost is lowered, the production efficiency is high, and the uniformity of the quality is good; secondly, the degree of mechanization is high, the procedure is simple, the yield is large, the mass production can be performed; thirdly, the waste of raw materials is reduced, the environment pollution is lowered; fourthly, the source of raw materials adopting nickel oxide ore or nickel-containing waste, the cost is low; fifthly, the waste resource can be recycled so as to save the resource consumption; and sixthly, the high-temperature pellets are directly smelted by adopting the lining electroslag furnace, the heat efficiency is high, the energy consumption is low, the material purity is high and the quality is good, and the device is simple with less investment.

The invention discloses a process of extracting white tungsten concentrate from tungstenic iron ores or tungstenic waste residues. The process comprises the following steps: after smashing tungstenic iron ores or tungstenic waste residues, mixing with sodium carbonate and double salt and pressing to form pellets; then, calcining at an appropriate temperature; leaching the calcined pellets by use of a ball-mill; then carrying out resin ion exchange, desorption, impurity removal and crystallization on leach liquor to finally obtain the white tungsten concentrate. The process can be used for effectively separating high grade white tungsten concentrate from tungstenic iron ores or tungstenic waste residues with extremely low grade of tungsten, is low in energy consumption, low in production cost, small in discharge capacity and environment-friendly, and can be used for effectively realizing comprehensive resource utilization, thereby satisfying the industrialized production.

The invention relates to a method for smelting stainless steel mother liquid by using chromium mineral powder and laterite as raw materials, which comprises the sequential steps of mixing, briquetting, proportioning, burning and smelting to obtain chromium-containing molten iron, wherein (1) mixing: uniformly mixing chromium mineral powder, laterite, coal powder or coke powder and composite binder; (2) briquetting: putting the mixture into a briquetting machine for briquetting, and then, drying or curing the briquettes to the specified strength; (3) proportioning: adding the dried or cured briquettes into a reduction accelerator and a slag preparing agent, and proportioning the briquettes, the reduction accelerator and the slag preparing agent; (4) smelting: adding the proportioned raw materials into a small blast furnace or new vertical furnace with an iron opening and an air opening from a furnace opening, and adding coke for smelting; and (5) tapping and transmitting the smelted chromium-bearing molten iron (i.e. stainless steel mother liquid) into steel works, or casting the smelted chromium-containing molten iron into iron ingots. The method for smelting stainless steel mother liquid by using chromium mineral powder and laterite as raw materials has lower production cost and reduces the environment pollution.

The invention discloses a direct reduction process for producing spongy iron from CH4-rich coal gas, which comprises the following steps: a, inputting CH4-rich coal gas subjected to pressure regulation and gas-based shaft furnace top gas sequentially subjected to cooling, dust removal and pressurization treatment into an outer converter, supplementing steam taken as modification reaction oxidizer of CH4 into the outer converter, and enabling CH4, H2O and CO2 in the outer converter to be subjected to modification reaction under the effect of a catalyst to generate high-temperature reducing coal gas mainly containing CO and H2; and b, inputting the high-temperature reducing coal gas generated in the outer converter into a gas-based shaft furnace to directly reduce iron ores to generate spongy iron. According to the invention, CO2 in the top gas is fully utilized to generate CO so as to provide reducing gas, thereby reducing the discharge of CO2, omitting the coal gas decarburization procedure and ensuring that the process is simple; and CH4 in the raw gas is subjected to thorough reaction, and the temperature of the high-temperature reducing coal gas is controlled at 850 DEG C, thereby realizing that the utilization efficiency of the raw gas is high, and avoiding the problems of blockage and shaft furnace cementation caused by a great amount of carbon precipitate of CH4 at high temperature.

The invention relates to a process and a device for preparing chromium iron by using chromium ore powder, which belongs to metallurgical industry steel-making raw material. The process comprises the following steps: mixing chromium iron containing raw materials with reducing agent, solvent and catalyst to prepare ultra fine powder, mixing to make pelletizing materials, sending the pelletizing materials into a reducing furnace, drying and roasting, and obtaining chromium irons after the reduction reaction. The reducing device is connected with an upper furnace above a furnace base, a lower furnace body is connected to the downside of the furnace base, the upper end of the upper furnace body is connected with an upper furnace mantle, a drying bed grate is positioned at the upper end in the upper furnace body, a purifying device is connected with the upper furnace body and the lower furnace body through pipelines, and a residual heat circulating device is connected with the lower furnace body. The invention has the advantages that: firstly, the reduction temperature is low, the reduction speed is high, the energy consumption is reduced, the production cost is lowered, the production efficiency is high, and the uniformity of the quality is ensured; secondly, the device is simple with less investment, the degree of mechanization is high, the procedure is simple, the yield is large, the mass production can be performed; thirdly, the waste of raw materials is reduced, the environment pollution is lowered; fourthly, the cost is low because the chromium ore powder and chromium-containing waste are adopted as raw materials; and fifthly, the waste resource can be recycled so as to save the resource consumption.

The invention provides a BAOSHEREX (Baosteel-Shenghua high efficiency smelting reduction) ironmaking process for smelting molten iron by a two-step method, which belongs to the technical field of ironmaking. The steps of the process comprise vertical furnace type prereduction; and additional arrangement of a melt gasification furnace outside a vertical prereduction furnace: oxygen gas and pulverized coal are sprayed from oxygen gas tuyeres which are uniformly distributed in the middle part of a furnace cylinder of the melt gasification furnace, and generated heat meets the requirements of generating molten iron and furnace slag. In the BAOSHEREX ironmaking process, coal accounts for 80-85 weight percent of fuel, only oxygen gas containing 500-600m<3> / t of iron and carbon coke accounting for 15-20 weight percent of the fuel are used for producing high-quality hot molten iron at a temperature of 1350-1480 DEG C, pelletized water granulated slag and high-quality coal gas. The BAOSHEREX ironmaking process has the advantages of high yield, high efficiency, low energy consumption, low emission and low cost.