CN110938725A - Efficient reduction system and method for metal oxide - Google Patents
Efficient reduction system and method for metal oxide Download PDFInfo
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- CN110938725A CN110938725A CN201911169300.1A CN201911169300A CN110938725A CN 110938725 A CN110938725 A CN 110938725A CN 201911169300 A CN201911169300 A CN 201911169300A CN 110938725 A CN110938725 A CN 110938725A
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Abstract
A system and a method for efficient reduction of metal oxides, comprising: the device comprises a combustion chamber, a heat accumulator, a reduction chamber, a flue, a material bearing ventilation platform, a reducing gas purification and quality improvement device and a first flue gas switch; the combustion chamber is arranged above the reduction chamber and is communicated with the reduction chamber; the heat accumulator is arranged between the combustion chamber and the reduction chamber and is of a ventilating structure; the lower end of the reduction chamber is communicated with the flue; the first flue gas switch is arranged between the reduction chamber and the flue; wherein, the material bearing ventilative platform sets up in reducing the indoor, and the bottom of material bearing ventilative platform is ventilative baffle, and the reducing gas purifies the bottom intercommunication of upgrading device's suction opening pipeline and material bearing ventilative platform. The technical scheme that this application provided through will heating and two steps of reduction separately, heats reducing gas through the heat accumulator simultaneously for reducing gas with heating material reaction also is high temperature gas, thereby improves material reduction effect, improves product quality.
Description
Technical Field
The invention relates to a high-efficiency reduction system for metal oxides, and belongs to the technical field of iron ore reduction. The invention also relates to a method for efficiently reducing the metal oxide.
Background
Since the end of the 18 th century, the direct reduction technology was conceived and the development began in the 60's of the 20 th century. There are tens of processes proposed in total, and there are two kinds of processes classified by the reducing agent used, namely, gas-based and coal-based processes. From the development of direct reduction, gas-based direct reduction methods always dominate (about 80%) regardless of the actual yield or production capacity of direct reduction, and coal-based direct reduction methods account for about 20%. The gas-based process is mainly focused on regions with abundant natural gas resources such as iran, saudi arabia, mexico and russia. And for other areas with abundant non-coking coal resources, the coal-based direct reduction process becomes the first choice. The coal-based direct reduction process mainly comprises a rotary kiln process, a rotary hearth furnace process and a tunnel kiln process according to production equipment classification.
In all coal-based direct reduction processes, the rotary kiln method is absolutely dominant, and 98% of the yield of coal-based direct reduced iron is produced by the coal-based rotary kiln. The main raw material of the rotary kiln method is oxidized pellets, the used reducing agent is mainly non-coking high-reactivity coal (sub-bituminous coal, bituminous coal and lignite), 80% of reduced coal and ore are added from the tail of the kiln, and 20% of reduced coal is sprayed from the head of the kiln. The reduction temperature is about 1050 ℃, the retention time of the raw materials in the kiln is about 10-12 h, about 800kg of reduced coal is consumed by each ton of sponge iron, and the net energy consumption is about 13.4GJ.t < -1 >. The problems of long flow, large investment, high overall energy consumption, long pellet retention time in the kiln, easy low-temperature reduction pulverization, product cracking, low kiln capacity utilization coefficient, large powder amount in the kiln, easy ring formation of the rotary kiln and the like exist, and further improvement is still needed.
The rotary hearth furnace method was used for the earliest time for the recovery of nickel, chromium and iron from alloy steel smelting waste, and it has proved to be feasible to produce sponge iron by this method. The main body equipment of the method is a circular furnace which is in a sealed disc shape, and the furnace body rotates by taking a vertical line as an axis in the motion. Mineral powder or metallurgical waste is used as an iron-containing raw material, and coke powder or coal is used as an internal reducing agent. The process comprises the following steps: mixing raw fuel evenly, grinding, pelletizing, continuously adding raw pellets into a rotary furnace, wherein the thickness of furnace charge is about 3 times of the diameter of the pellets, and heating and roasting the pellets by adopting a natural gas, coal or coal burning nozzle at the reduction temperature of 1250-1350 ℃. The main problems encountered with this process are: the heating of the rotary hearth furnace completely depends on radiation heat transfer, combustion flame and combustion waste gas can not contact the material layer of the carbon-containing pellets, the heat supply and the reduction potential are ensured to be a pair of spears, and the metallization rate of the product is not high (70-80%); the equipment is similar to a ring-shaped heating furnace, the structure is complex, and the operating cost is higher; the production control requirement is high, and the production stability (product quality and equipment operation) does not reach the expected level.
The tunnel kiln method is one of the oldest direct reduction iron making methods, and is generally used only for one reduction process of powder metallurgy reduced iron powder production. The method has low technical content, is suitable for small-scale production, has small investment, meets the investment requirement of small enterprises, and increases or decreases the heat tide of recent construction. The tunnel kiln method has the problems of low thermal efficiency, high energy consumption (reduced coal is 450-650 k/t.DRI, and heating coal is 450-550 kg/t.DRI), long production period (48-76 h), serious pollution (more solid wastes such as reduced coal ash and waste reduction tank, more dust), unstable product quality, difficult expansion of single-machine production capacity and the like, and is difficult to meet the development requirement of the steel industry.
At present, the scale of the steel industry is continuously enlarged, the steel production technology is continuously developed and perfected, and the process flow is continuously developed towards the direction of compactness, high efficiency, continuity, high cleanness and environmental friendliness. The main process of steel production is coking, sintering → blast furnace ironmaking → converter steelmaking (also called long process), there are obvious unreasonable places (such as the situation that oxygen level and carbon level change repeatedly in blast furnace ironmaking-converter steelmaking), and the energy consumption of the traditional long-process coking, sintering and other auxiliary processes accounts for 60% -70% of the energy consumption of steel production. In addition, the long process pollution of the traditional steel production is serious, the method is a pollution large household of national production, and particularly the sintering and coking processes in iron-making production have higher pollution emission indexes and more pollutant types, and the method is a main object of environmental management. In recent years, with the rise of short flow of "direct reduction-electric furnace steelmaking", direct reduction technology has been attracting much attention as an effective means for utilizing complex multi-metal resources. Due to the difference of resource conditions, the development emphasis of the direct reduction process is different at home and abroad. China takes coal as a main energy source and focuses on a coal-based direct reduction process, including the processes of a rotary kiln, a rotary hearth furnace, a tunnel kiln and the like, but the method can not realize better breakthrough and development.
In summary, most of the existing coal-based direct reduction technologies have the problems of low production efficiency, heavy energy consumption pollution, poor product quality, and the like, so how to provide a metal oxide efficient reduction system can improve the production efficiency, reduce the energy consumption, and improve the product quality is a problem that needs to be broken through and solved urgently by technical personnel in the field.
Disclosure of Invention
In view of the above-mentioned disadvantages of the prior art, the present invention is directed to improve the material reduction effect and improve the product quality by separating the heating and reduction steps and heating the reducing gas through the heat accumulator, so that the reducing gas reacting with the heated material is also a high-temperature gas. The invention provides a metal oxide efficient reduction system, which comprises: the device comprises a combustion chamber, a heat accumulator, a reduction chamber, a flue, a material bearing ventilation platform, a reducing gas purification and quality improvement device and a first flue gas switch; the combustion chamber is arranged above the reduction chamber and is communicated with the reduction chamber; the heat accumulator is arranged between the combustion chamber and the reduction chamber and is of a ventilating structure; the lower end of the reduction chamber is communicated with the flue; the first flue gas switch is arranged between the reduction chamber and the flue; wherein, the material bearing ventilative platform sets up in reducing the indoor, and the bottom of material bearing ventilative platform is ventilative baffle, and the reducing gas purifies the bottom intercommunication of upgrading device's suction opening pipeline and material bearing ventilative platform.
According to a first embodiment of the present invention, there is provided a metal oxide high efficiency reduction system:
a metal oxide high efficiency reduction system, the system comprising: the device comprises a combustion chamber, a heat accumulator, a reduction chamber, a flue, a material bearing ventilation platform, a reducing gas purification and quality improvement device and a first flue gas switch;
the combustion chamber is arranged above the reduction chamber and is communicated with the reduction chamber; the heat accumulator is arranged between the combustion chamber and the reduction chamber and is of a ventilating structure; the lower end of the reduction chamber is communicated with the flue; the lower end of the reduction chamber is connected with the flue through a first flue gas switch; the material bearing and ventilating platform is arranged in the reduction chamber, the bottom of the material bearing and ventilating platform is a ventilating partition plate, and the reducing gas purifying and upgrading device is communicated with the bottom of the material bearing and ventilating platform through an air suction opening pipeline; the reducing gas conduit is in communication with the combustion chamber.
Preferably, the first air outlet of the reducing gas purifying and upgrading device is communicated with the combustion chamber through a reducing gas pipeline.
Preferably, the system further comprises: a first heat exchanger; the first heat exchanger is arranged on the reducing gas pipeline and is positioned in the flue; the reducing gas exchanges heat with the flue gas in the flue through the first heat exchanger.
Preferably, a gas burner is arranged at the top of the combustion chamber; and a combustion-supporting gas nozzle is arranged in the combustion chamber.
Preferably, the combustion-supporting gas nozzle is located on one side of the gas burner.
Preferably, the sidewall of the reduction chamber is provided with a re-burner.
Preferably, the system further comprises: the second heat exchanger is arranged on the third pipeline, and the second heat exchanger is positioned in the flue; and combustion-supporting gas is communicated with the combustion-supporting gas nozzle through a third pipeline, and the combustion-supporting gas exchanges heat with flue gas in the flue through a second heat exchanger.
Preferably, the system further comprises: a dry distillation chamber; the bottom of the dry distillation chamber is communicated with the flue; and a dry distillation outlet at the top of the dry distillation chamber is communicated with the gas burner through a fourth pipeline.
Preferably, the system further comprises: a loading area and a first material transportation switch; the charging area is arranged at one side of the dry distillation chamber; the first material transportation switch is arranged between the loading area and the dry distillation chamber.
Preferably, the system further comprises: a cooling chamber; the bottom of the cooling chamber is communicated with a second air outlet of the reducing gas purifying and upgrading device through a fifth pipeline; and a gas outlet at the top of the cooling chamber is communicated with the combustion chamber through a sixth pipeline.
Preferably, the flue is a dual-purpose flue for flue gas conveying and material transferring; the material which is carbonized in the carbonization chamber is transferred into the reduction chamber through the flue.
Preferably, the cooling chamber is disposed on the flue, and the material reduced in the reduction chamber is transferred into the cooling chamber through the flue.
Preferably, the cooling chamber is arranged on the flue, and the system further comprises: a second material transportation switch and a third material transportation switch; the second material transportation switch and the third material transportation switch are sequentially arranged on the flue, and a cooling chamber is formed between the second material transportation switch and the third material transportation switch.
Preferably, the system further comprises: a discharge area; the discharging area is arranged on the flue and is separated from the cooling chamber by a third material transportation switch.
Preferably, the system comprises a plurality of groups of material reduction cooling unloading modules which are formed by combining the combustion chamber, the heat accumulator, the reduction chamber, the cooling chamber and the unloading area, and the plurality of groups of material reduction cooling unloading modules are arranged along the length direction of the flue.
Preferably, the flue comprises a main flue, an auxiliary flue and a fourth material transportation switch; the combustion chamber, the heat accumulator and the reduction chamber are positioned above the main flue or the auxiliary flue, and the cooling chamber and the unloading area are arranged in the auxiliary flue; the main flue and the auxiliary flue are separated by a fourth material transportation switch.
Preferably, the system comprises a plurality of groups of feeding dry distillation modules formed by combining the charging area and the dry distillation chamber, and the plurality of groups of feeding dry distillation modules are arranged along the length direction of the flue.
According to a second embodiment of the present invention, there is provided a method for the efficient reduction of a metal oxide:
a method for efficiently reducing a metal oxide, which is applied to the system for efficiently reducing a metal oxide according to the first embodiment, comprising the steps of:
1) the method comprises the following steps of placing a material containing biomass and metal oxide in a reduction chamber, burning and heating the material containing the biomass and the metal oxide in the reduction chamber by a burner in a combustion chamber, simultaneously heating a heat accumulator 2 which is in the same heating space with the material, and enabling generated high-temperature flue gas to enter a flue;
2) heating the material to a certain temperature to obtain a high-temperature material, and stopping heating the material and the heat accumulator;
3) sealing the space between the heat accumulator and the material, and pumping out the reducing gas purifying and upgrading device from the bottom of the material and collecting low-quality reducing tail gas B in the material and between the heat accumulator and the material;
4) the low-quality reduction tail gas B is treated by a reduction gas purification and quality improvement device and is subjected to H removal2O and CO2 to obtain reducing gas A;
5) and when the content of the low-quality reduction tail gas B extracted from the bottom of the material is detected to be obviously reduced, introducing reducing gas to the other side of the heat accumulator opposite to the material, heating the reducing gas by the heat accumulator and then introducing the reducing gas into the reduction chamber, and deeply reducing the high-temperature material in the reduction chamber by the reducing gas to obtain a deep reduction material.
Preferably, the method further comprises:
1a) the material containing the biomass and the metal oxide is loaded in the loading area, the material containing the biomass and the metal oxide and loaded is conveyed to the dry distillation chamber for pretreatment, dry distillation objects generated by the dry distillation chamber are conveyed to the combustion chamber through a fourth pipeline, and the material containing the biomass and the metal oxide and pretreated by the dry distillation chamber is conveyed to the reduction chamber for treatment.
Preferably, the method further comprises the following steps: and 6) conveying the deep reduced material obtained after deep reduction treatment in the reduction chamber to a cooling chamber for cooling.
Preferably, in the step 1), the combustion-supporting gas passes through the second heat exchanger, is subjected to heat exchange with the flue gas in the flue to raise the temperature, and is then conveyed into the combustion chamber, and the burner in the combustion chamber combusts and heats the material containing the biomass and the metal oxide in the reduction chamber.
Preferably, in the step 5), the reducing gas exchanges heat with the flue gas in the flue through the first heat exchanger to be heated, or the reducing gas exchanges heat with the high-temperature material in the cooling chamber to be heated through the cooling chamber, then the reducing gas is conveyed into the combustion chamber, and then the reducing gas is heated by the heat accumulator and then introduced into the reduction chamber.
In a first embodiment, the combustion is disposed adjacent to the reduction chamber, preferably, the combustion chamber is disposed above the reduction chamber; igniting in the combustion chamber to heat the material in the reduction chamber. In the process of heating the materials by the combustion chamber, the combustion chamber also heats a heat accumulator arranged between the combustion chamber and the reduction chamber so as to store heat in advance. The high-temperature flue gas after heating the heat accumulator and the material enters the flue through a communicating part of the reduction chamber and the flue. The first smoke switch can control the connection and disconnection of the reduction chamber and the flue. After the heat accumulator and the materials are heated, the first smoke switch is closed, reducing gas is introduced into the combustion chamber through the reducing gas pipeline, and the reducing gas is heated by utilizing the waste heat and the heat accumulator in the combustion chamber. Meanwhile, under the action of the reducing gas purifying and upgrading device, reducing gas entering the combustion chamber enters the reduction chamber through the heat accumulator, and the gas in the reduction chamber only can pass through the material and enters the reducing gas purifying and upgrading device from the bottom of the material through the air inlet pipeline. In the process, the materials are taken as the necessary channel for the gas in the reduction chamber to be discharged, the materials can carry out deep reduction reaction with high-temperature reducing gas, and the quality of material reduction is improved. Thereby creating excellent material and temperature conditions for efficient reduction and solving the problem that a heat tool and a high reduction potential condition are contradictory in the direct reduction process. Finally, the production efficiency is improved, the energy consumption is reduced, and the product quality is improved.
It should be noted that all the flame or high-temperature gas generated in the combustion chamber passes through the heat accumulator and then enters the reduction chamber to heat the material.
The material bearing and ventilating platform is arranged at the bottom of the reduction chamber, and a gap is formed between the periphery of the material bearing and ventilating platform and the inner wall of the reduction chamber; the first smoke switch is arranged between the material bearing ventilating table and the reduction chamber. After the material bearing ventilating platform is moved into the reduction chamber, an annular gap is formed between the periphery of the material bearing ventilating platform and the reduction chamber. The annular gap is communicated with the flue, and the first flue gas switch is used for controlling the on-off between the annular gap and the flue.
In a first embodiment, biomass is converted in a reduction chamber from biomass-containing material at elevated temperature, the biomass being dehydrated and CO-removed2Producing high-quality hydrogen-rich reducing gas. In the process of heating the reduction chamber through the combustion chamber, the reducing gas purification and quality improvement device is started, and hydrogen-rich reducing gas generated by biomass in the materials (iron minerals) in the stage is continuously extracted and collected. The hydrogen-rich reducing gas produced is then passed through a reducing gas line into the combustion chamber. Therefore, hydrogen-rich reducing gas generated by the biomass is used for strengthening the reduction process in the key stage in the later stage, the characteristics of the components of the biomass are fully and reasonably utilized, and the reduction efficiency is obviously improved. In a further preferred embodiment, the reducing gas duct also recovers heat in the flue via a first heat exchanger. Thereby reducing the temperature rise dependence on the heat accumulator, effectively prolonging the time of deep reduction after combustion is stopped, and improving the product quality.
In a first embodiment, a flame is generated in the combustion chamber by the cooperation of an internal combustion nozzle and a combustion gas inlet, and the material and the heat accumulator are heated. Furthermore, the lateral wall of the reduction chamber is also provided with a reburning nozzle, so that oxidizing gas in the reduction chamber is fully utilized and consumed, and the heating of materials is facilitated.
In the first embodiment, the combustion-supporting gas is heated in the flue by the second heat exchanger, so that the combustion value of the fuel in the combustion chamber is improved, and the combustion efficiency is improved.
In the first embodiment, the high-temperature flue gas in the flue can also be used for carrying out dry distillation on the materials which are just assembled in the dry distillation chamber, and the combustible gas generated by the dry distillation is connected into the combustion nozzle and is used for combustion in the combustion chamber, so that the resources generated by the dry distillation are reasonably utilized, and the consumption of heat is reduced.
In a first embodiment, the loading zone is arranged on one side of the retort chamber. After the material assembly is completed, the material can be quickly placed into the dry distillation chamber for dry distillation, so that the operation time is saved, and the production efficiency is improved.
In a first embodiment, the cooling chamber is used to cool the material after deep reduction, since the material is still at a higher temperature. If the reduced material contacts oxidizing gas, partial material oxidation will be caused to affect the product quality. Therefore, reducing gas is generally introduced into the reduction chamber, so that the cooling chamber maintains a reducing atmosphere. In this scheme, the hydrogen-rich reducing gas that has living beings to produce can also let in the cooling chamber, and hydrogen-rich reducing gas provides the reducing atmosphere for the cooling of material on the one hand, and on the one hand, the material after the reduction that has the waste heat still can heat the preheating to hydrogen-rich reducing gas. The temperature of the hydrogen-rich reducing gas before entering the combustion chamber is increased, so that the deep reduction time is prolonged, and the product quality is improved.
In a first embodiment, the flue is used for flue gas transport as well as a material transfer channel. The materials move in the flue, the materials after the dry distillation enter the reduction chamber from the dry distillation chamber through the flue for reduction, and the materials after the reduction enter the cooling chamber through the flue for cooling.
The cooling chamber is formed by isolating a second material transportation switch and a third material transportation switch on a flue, and the second material transportation switch and the third material transportation switch are controlled to be opened and closed to cooperate with materials to enter and move out of the cooling chamber.
In the first embodiment, the device further comprises a discharging area, wherein the discharging area is arranged on the flue, and the discharging area is arranged on the other side of the third material transportation switch of the cooling chamber.
In the first embodiment, the multiple groups of material reduction, cooling and discharging modules are arranged on the flue, the flue is divided into a main flue and an auxiliary flue, the combustion chamber, the heat accumulator and the reduction chamber are positioned above the main flue or the auxiliary flue, and the cooling chamber and the discharging area are arranged in the auxiliary flue. The multi-group material reduction cooling discharging module enables the system to meet the reduction work of a large number of materials, and meanwhile, the occupied area of equipment is reduced. Is beneficial to reducing the production cost of enterprises.
In the first embodiment, a plurality of groups of feeding dry distillation modules are arranged on the flue, so that the dry distillation efficiency of materials can be improved.
In a second embodiment, the heat accumulator and the material containing biomass in the reduction chamber are heated simultaneously, the material is heated to a certain temperature to obtain a high-temperature material, and the heating of the material and the heat accumulator is stopped. At the moment, the biomass is pyrolyzed and the reducing gas formed by the pre-reduction reaction of the biomass and the iron material is extracted from the bottom of the material. And when the content of the extracted low-quality reduction tail gas B is obviously reduced, introducing reducing gas A to the other side of the heat accumulator opposite to the material, and reacting the reducing gas A with the high-temperature material after the reducing gas A is added through the heat accumulator to deeply reduce the material.
In the second embodiment, the reducing gas A is specifically oxygen-enriched reducing gas B extracted from the bottom of the material, and the oxygen-enriched reducing gas B is introduced into the reducing chamber after being heated by the first heat exchanger or the cooling chamber, so that the energy loss is reduced.
It is further explained that, as shown in fig. 1, firstly, the iron-containing raw material and the biomass are mixed in a certain proportion in a charging area and then enter the dry distillation chamber. The dry mixed material in the dry distillation chamber enters a direct reduction chamber, the material is placed on a grate plate, and the bottom of the grate plate is connected with a reducing gas purifying and upgrading device through an air suction opening pipeline. And a gas burner and an oxygen-enriched nozzle are started to supply heat by combustion, a heat accumulator, materials and a hearth of a reduction area are heated, a reducing gas pipeline is closed at the moment, high-temperature flue gas is fully combusted by a reburning nozzle and then enters a flue from a first flue gas switch at the bottom of the hearth, and a heat exchanger is arranged in the flue and used for preheating combustion-supporting air/oxygen-enriched and reducing gas. After the mixed material is heated to a certain temperature (the pre-reduction is started), gradually closing the gas burner and the combustion-supporting gas nozzle, then closing the re-burner and a first flue gas switch at the bottom of the hearth, and opening the reducing gas purification and quality improvement device at the lower part of the grate plate. At the moment, the biomass pyrolysis and the reducing gas formed by the pre-reduction reaction of the biomass pyrolysis and the iron material are collected by a reducing gas purification and quality improvement device, dehydrated, and subjected to CO2 removal, and then the biomass pyrolysis and the reducing gas are preheated by a first heat exchanger or a cooling chamber. And (3) obviously reducing the reducing gas quantity of the to-be-reduced gas purifying and upgrading device, reducing the negative pressure of air draft, introducing the preheated hydrogen-rich reducing gas into the combustion chamber, and then exchanging heat with the heat accumulator to form high-temperature hydrogen-rich reducing gas. High-temperature hydrogen-rich reducing gas enters the material to complete the deep reduction of the material, and the positive pressure level of the combustion chamber is maintained in the process. And after the reduction process is finished, closing the reducing gas pipeline, starting the reducing gas purifying and upgrading device, transferring the high-temperature reduced material to the cooling chamber for cooling, and then finishing unloading. Repeating the steps and entering the treatment of the next batch of materials.
As shown in figure 2, a plurality of material reduction cooling unloading modules can be arranged on the main flue, and the reduction processes are alternately carried out to form continuous production.
The technical scheme provided by the application is that,
aiming at the problem of insufficient atmosphere supply in the later stage of the reduction process caused by CO escape, the invention arranges the flue outlet at the bottom of the material layer, adopts pressurization operation, and the material layer becomes a diffusion path which is necessary for gas discharge, thereby ensuring sufficient atmosphere conditions in the material layer in the reduction process, improving the reduction efficiency and the quality of the reduction product, and breaking through the core bottleneck of the existing coal-based direct reduction process. In the invention, the characteristics of high volatile component and hydrogen enrichment of biomass are considered, iron minerals are used for converting the biomass in the early reduction process, and the high-quality hydrogen-enriched reducing gas is prepared after dehydration and CO2 and is creatively used for strengthening the reduction process in the key stage in the later period, so that the characteristics of the components of the biomass are fully and reasonably utilized, and the reduction efficiency is obviously improved.
Aiming at the common problem that the direct reduction heat supply and the reduction potential guarantee that two major factors are difficult to be considered, the invention independently separates the combustion heat supply and the reduction of a key stage (later stage); in the early stage, the material is heated through the heat accumulator in a fuel combustion mode, and the heat accumulator is heated at the same time; then, the combustion burner is cut off to introduce hydrogen-rich reducing gas (converted from biomass), and the hydrogen-rich reducing gas directly carries heat into the material layer through heat exchange with the heat accumulator, so that continuous supply of heat in the reduction process is ensured, and high reduction potential in the system is not damaged; creates excellent material and temperature conditions for efficient reduction, and solves the common problem of contradiction between heat supply and high reduction potential conditions in the direct reduction process.
The method not only can effectively utilize abundant but idle biomass resources, but also has the advantages of short flow, low investment, high efficiency, low energy consumption, environmental friendliness and the like, and can realize the efficient direct reduction of metal oxide resources.
In the prior art, the disadvantages of each type of process are as follows:
the kiln raw material of the rotary kiln process is oxidized pellet ore, the process of grinding ore, pelletizing, roasting and the like is needed for obtaining the oxidized pellet ore, and the rotary kiln process has the disadvantages of long flow, large investment and high energy consumption; the temperature is low (the kiln temperature needs to be strictly controlled at 1050 ℃), the reduction time is long (the retention time of the raw materials in the kiln is about 10-12 h), and the low efficiency is the disadvantage II; the ring formation of the rotary kiln is easily caused by the crushing and pulverization generated in the reduction process, the ring formation is avoided by strictly controlling the temperature of the rotary kiln and also serving as the root source, and the defect of unstable production is the third defect; the difficulty of diffusing CO generated by coal gasification in a material layer to the interior of iron minerals is far greater than the difficulty of diffusing CO to the interior of iron minerals, namely most of CO escapes instead of participating in reduction, so that the CO is not supplied enough in a key metallization stage (the later stage of the reduction process), and the disadvantages of low operation temperature of the rotary kiln and insufficient heat supply are superposed, thereby causing the effects of long time consumption, low efficiency and poor product quality of the direct reduction process and being the common problem existing in the existing coal-based direct reduction process.
The rotary hearth furnace process heating completely depends on radiation heat transfer, combustion flame and combustion waste gas can not contact the material layer of the pellets completely, and low heat transfer efficiency is one of the defects; the generation of heat depends on the sufficient combustion of fuel, thereby influencing the concentration of the reducing atmosphere in the rotary hearth furnace, ensuring that the heat supply and the reducing potential are a pair of spears, and both are necessary conditions for the reduction process to be carried out sufficiently, and are the second defects; as a common problem, the reduction process caused by the slip has insufficient CO supply, which is the third disadvantage; the rotary hearth furnace has the fourth defect that the structure is complex, the operating cost is high, the production control requirement is high, and the production stability is poor.
The tunnel kiln process adopts an external heating mode, and has the disadvantages of low thermal efficiency, high energy consumption, long production period and serious pollution; similarly, the deficiency of CO supply at the later stage of the reduction process caused by the escape is the second disadvantage; the product quality is unstable, and the single machine production capacity is small, which is the disadvantage three.
Compared with the prior art, the invention has the following beneficial effects:
1. according to the technical scheme provided by the invention, the characteristics of cleanness and high activity of biomass energy are fully utilized, and an innovative thermal field and reduction field control technology system is combined, so that a system integration technology is provided for the direct reduction of metal oxide, the production efficiency is improved, and the product quality is improved;
2. the technical scheme provided by the invention effectively utilizes the renewable energy of biomass energy, has the characteristics of wide adaptability, short flow, high efficiency and environmental protection, reduces the emission of pollutants and improves the environmental protection level.
Drawings
FIG. 1 is a schematic structural diagram of a core heating reduction zone of a metal oxide efficient reduction system in an embodiment provided by the present invention;
FIG. 2 is a schematic diagram of the overall structure of a metal oxide reduction system according to an embodiment of the present invention;
fig. 3 is a schematic layout diagram of a metal oxide efficient reduction system in an embodiment of the present invention.
Reference numerals:
1: a combustion chamber; 101: a gas burner; 102: a combustion-supporting gas nozzle; 2: a heat accumulator; 3: a reduction chamber; 301: then burning the mouth; 4: a flue; 401: a main flue; 402: a secondary flue; 5: a material bearing ventilation platform; 6: a reducing gas purification and quality improvement device; 7: a dry distillation chamber; 701: a dry distillate outlet; 8: a loading area; 9: a cooling chamber; 10: a discharge area; h1: a first heat exchanger; h2: a second heat exchanger;
l1: an air suction opening pipeline; l2: a reducing gas conduit; l3: a third pipeline; l4: a fourth conduit; l5: a fifth pipeline; l6: a sixth pipeline; k1: a first flue gas switch; w1: a first material transport switch; w2: a second material transport switch; w3: a third material transport switch; w4: and a fourth material transportation switch.
Detailed Description
According to a first embodiment of the present invention, there is provided a metal oxide high efficiency reduction system:
a metal oxide high efficiency reduction system, the system comprising: the device comprises a combustion chamber 1, a heat accumulator 2, a reduction chamber 3, a flue 4, a material bearing ventilation platform 5, a reducing gas purifying and quality improving device 6 and a first flue gas switch K1; wherein the combustion chamber 1 is arranged above the reduction chamber 3, and the combustion chamber 1 is communicated with the reduction chamber 3; the heat accumulator 2 is arranged between the combustion chamber 1 and the reduction chamber 3, and the heat accumulator 2 is of a ventilation structure; the lower end of the reduction chamber 3 is communicated with a flue 4; the lower end of the reduction chamber 3 is connected with the flue 4 through a first flue gas switch K1; the material bearing ventilating platform 5 is arranged in the reduction chamber 3, the bottom of the material bearing ventilating platform 5 is a ventilating partition plate, and the reducing gas purifying and quality improving device 6 is communicated with the bottom of the material bearing ventilating platform 5 through an air suction opening pipeline L1; the reducing gas duct L2 communicates with the combustor 1.
Preferably, the first air outlet of the reducing gas purifying and upgrading device 6 is communicated with the combustion chamber 1 through a reducing gas pipeline L2.
The system further comprises: a first heat exchanger H1; the first heat exchanger H1 is disposed on the reducing gas duct L2, and the first heat exchanger H1 is located inside the flue 4; the reducing gas exchanges heat with the flue gas in the flue 4 through a first heat exchanger H1.
Preferably, a gas burner 101 is arranged in the combustion chamber 1; the combustion chamber 1 is provided with a combustion-supporting gas nozzle 102.
Preferably, the combustion-supporting gas nozzle 102 is located on the side of the gas burner 101.
Preferably, the re-burning nozzle 301 is provided on the side wall of the reduction chamber 3.
Preferably, the system further comprises: a second heat exchanger H2 and a third conduit L3, the second heat exchanger H2 being disposed on the third conduit L3, and the second heat exchanger H2 being located within the flue 4; the combustion-supporting gas is communicated with the combustion-supporting gas nozzle 102 through a third pipeline L3, and the combustion-supporting gas exchanges heat with the flue gas in the flue 4 through a second heat exchanger H2.
Preferably, the system further comprises: a dry distillation chamber 7; the bottom of the dry distillation chamber 7 is communicated with the flue 4; the dry distillation outlet 701 at the top of the dry distillation chamber 7 is communicated with the gas burner 101 through a fourth pipeline L4.
Preferably, the system further comprises: a loading area 8, a first material transportation switch W1; the charging area 8 is arranged at one side of the dry distillation chamber 7; the first material transporting switch W1 is provided between the charging zone 8 and the retort chamber 7.
Preferably, the system further comprises: a cooling chamber 9; the bottom of the cooling chamber 9 is communicated with a second air outlet of the reducing gas purifying and upgrading device 6 through a fifth pipeline L5; the gas outlet at the top of the cooling chamber 9 communicates with the combustion chamber 1 through a sixth conduit L6.
Preferably, the flue 4 is a dual-purpose flue for flue gas conveying and material transferring; the material distilled in the dry distillation chamber 7 is transferred to the reduction chamber 3 through the flue 4.
Preferably, the cooling chamber 9 is disposed in the flue 4, and the material reduced in the reduction chamber 3 is transferred into the cooling chamber 9 through the flue 4.
Preferably, the cooling chamber 9 is arranged in the flue 4, and the system further comprises: a second material transportation switch W2, a third material transportation switch W3; the second material transportation switch W2 and the third material transportation switch W3 are sequentially disposed on the flue 4, and a cooling chamber 9 is formed between the second material transportation switch W2 and the third material transportation switch W3.
Preferably, the system further comprises: a discharge zone 10; a discharge area 10 is arranged on the flue 4, which discharge area 10 is separated from the cooling chamber 9 by a third material transport switch W3.
Preferably, the system comprises a plurality of groups of material reduction cooling discharging modules which are formed by combining the combustion chamber 1, the heat accumulator 2, the reduction chamber 3, the cooling chamber 9 and the discharging area 10, and the plurality of groups of material reduction cooling discharging modules are arranged along the length direction of the flue 4.
Preferably, the flue 4 comprises a main flue 401, a secondary flue 402 and a fourth material transportation switch W4; the combustion chamber 1, the heat accumulator 2 and the reduction chamber 3 are positioned above the main flue 401 or the auxiliary flue 402, and the cooling chamber 9 and the discharging area 10 are arranged in the auxiliary flue 402; main tunnel 401 is separated from secondary tunnel 402 by a fourth material transport switch W4.
Preferably, the system comprises a plurality of groups of feeding dry distillation modules formed by combining the charging area 8 and the dry distillation chamber 7, and the plurality of groups of feeding dry distillation modules are arranged along the length direction of the flue 4.
According to a second embodiment of the present invention, there is provided a method for the efficient reduction of a metal oxide:
a metal oxide high-efficiency reduction method applied to the metal oxide high-efficiency reduction system according to the first embodiment, comprising the steps of:
1) the method comprises the following steps of placing a material containing biomass and metal oxide in a reduction chamber 3, carrying out combustion heating on the material containing the biomass and the metal oxide in the reduction chamber 3 by a burner in a combustion chamber 1, simultaneously heating a heat accumulator 2 which is in the same heating space with the material, and feeding generated high-temperature flue gas into a flue 4;
2) heating the material to a certain temperature to obtain a high-temperature material, and stopping heating the material and the heat accumulator 2;
3) sealing the space between the heat accumulator 2 and the material, and pumping out the reducing gas purifying and upgrading device 6 from the bottom of the material and collecting low-quality reducing tail gas B in the material and between the heat accumulator 2 and the material;
4) the low-quality reduction tail gas B is treated by a reduction gas purification and quality improvement device 6 and is subjected to H removal2O and CO2 to obtain reducing gas A;
5) and when the content of the low-quality reduction tail gas B extracted from the bottom of the material is detected to be obviously reduced, introducing reducing gas A to the other side of the heat accumulator opposite to the material, heating the reducing gas A by the heat accumulator 2 and then introducing the reducing gas A into the reduction chamber 3, and deeply reducing the high-temperature material in the reduction chamber 3 by the reducing gas A to obtain a deep reduction material.
Preferably, the method further comprises:
1a) the material containing the biomass and the metal oxide is loaded in the loading area 8, the material containing the biomass and the metal oxide and loaded is conveyed to the dry distillation chamber 7 to be pretreated, dry distillation objects generated by the dry distillation chamber 7 are conveyed to the combustion chamber 1 through a fourth pipeline L4, and the material containing the biomass and the metal oxide and pretreated by the dry distillation chamber 7 is conveyed to the reduction chamber 3 to be treated.
Preferably, the method further comprises the following steps: and 6) conveying the deep reduced material obtained after deep reduction treatment in the reduction chamber 3 to a cooling chamber 9 for cooling.
Preferably, in the step 1), the combustion-supporting gas passes through the second heat exchanger H2, is subjected to heat exchange with the flue gas in the flue 4 to raise the temperature, and is then conveyed into the combustion chamber 1, and the burner in the combustion chamber 1 combusts and heats the material containing the biomass and the metal oxide in the reduction chamber 3.
Preferably, in the step 5), the reducing gas a exchanges heat with flue gas in the flue 4 through the first heat exchanger H1 to raise the temperature, or the reducing gas a exchanges heat with high-temperature materials in the cooling chamber 9 to raise the temperature through the cooling chamber 9, and then is conveyed into the combustion chamber 1, and then is heated by the heat accumulator 2 and then is introduced into the reduction chamber 3.
Example 1
A metal oxide high efficiency reduction system, comprising: the device comprises a combustion chamber 1, a heat accumulator 2, a reduction chamber 3, a flue 4, a material bearing ventilation platform 5, a reducing gas purifying and quality improving device 6 and a first flue gas switch K1; wherein the combustion chamber 1 is arranged above the reduction chamber 3, and the combustion chamber 1 is communicated with the reduction chamber 3; the heat accumulator 2 is arranged between the combustion chamber 1 and the reduction chamber 3, and the heat accumulator 2 is of a ventilation structure; the lower end of the reduction chamber 3 is communicated with a flue 4; the lower end of the reduction chamber 3 is connected with the flue 4 through a first flue gas switch K1; the material bearing ventilating platform 5 is arranged in the reduction chamber 3, the bottom of the material bearing ventilating platform 5 is a ventilating partition plate, and the reducing gas purifying and quality improving device 6 is communicated with the bottom of the material bearing ventilating platform 5 through an air suction opening pipeline L1; the reducing gas duct L2 communicates with the combustor 1.
Example 2
Example 1 is repeated, except that the first air outlet of the reducing gas purifying and upgrading device 6 is communicated with the combustion chamber 1 through a reducing gas pipeline L2.
Example 3
Example 2 is repeated except that the system further comprises: a first heat exchanger H1; the first heat exchanger H1 is disposed on the reducing gas duct L2, and the first heat exchanger H1 is located inside the flue 4; the reducing gas exchanges heat with the flue gas in the flue 4 through a first heat exchanger H1.
Example 4
Example 3 was repeated except that a gas burner 101 was provided in the combustion chamber 1; the combustion chamber 1 is provided with a combustion-supporting gas nozzle 102. The combustion-supporting gas nozzle 102 is located on one side of the gas burner 101. The reduction chamber 3 is provided with a re-burning nozzle 301 on a side wall thereof.
Example 5
Example 4 was repeated except that the system further included: a second heat exchanger H2 and a third conduit L3, the second heat exchanger H2 being disposed on the third conduit L3, and the second heat exchanger H2 being located within the flue 4; the combustion-supporting gas is communicated with the combustion-supporting gas nozzle 102 through a third pipeline L3, and the combustion-supporting gas exchanges heat with the flue gas in the flue 4 through a second heat exchanger H2.
Example 6
Example 5 was repeated except that the system further included: a dry distillation chamber 7; the bottom of the dry distillation chamber 7 is communicated with the flue 4; the dry distillation outlet 701 at the top of the dry distillation chamber 7 is communicated with the gas burner 101 through a fourth pipeline L4.
Example 7
Example 6 is repeated except that the system further comprises: a loading area 8, a first material transportation switch W1; the charging area 8 is arranged at one side of the dry distillation chamber 7; the first material transporting switch W1 is provided between the charging zone 8 and the retort chamber 7.
Example 8
Example 7 is repeated except that the system further comprises: a cooling chamber 9; the bottom of the cooling chamber 9 is communicated with a second air outlet of the reducing gas purifying and upgrading device 6 through a fifth pipeline L5; the gas outlet at the top of the cooling chamber 9 communicates with the combustion chamber 1 through a sixth conduit L6.
Example 9
Example 8 is repeated except that the flue 4 is a dual-purpose flue for flue gas conveying and material transferring; the material distilled in the dry distillation chamber 7 is transferred to the reduction chamber 3 through the flue 4.
Example 10
Example 9 was repeated except that the cooling chamber 9 was disposed in the flue 4 and the material reduced in the reduction chamber 3 was transferred to the cooling chamber 9 through the flue 4.
Example 10
Example 9 is repeated except that the cooling chamber 9 is provided in the flue 4. in particular, the system further comprises: a second material transportation switch W2, a third material transportation switch W3; the second material transportation switch W2 and the third material transportation switch W3 are sequentially disposed on the flue 4, and a cooling chamber 9 is formed between the second material transportation switch W2 and the third material transportation switch W3.
Example 11
Example 10 is repeated except that the system further comprises: a discharge zone 10; a discharge area 10 is arranged on the flue 4, which discharge area 10 is separated from the cooling chamber 9 by a third material transport switch W3.
Example 12
Example 11 is repeated except that the system includes a plurality of groups of material reduction cooling discharging modules formed by combining the combustion chamber 1, the heat accumulator 2, the reduction chamber 3, the cooling chamber 9 and the discharging area 10, and the plurality of groups of material reduction cooling discharging modules are arranged along the length direction of the flue 4.
Example 13
Example 12 is repeated except that stack 4 includes main stack 401, secondary stack 402, fourth material transport switch W4; the combustion chamber 1, the heat accumulator 2 and the reduction chamber 3 are positioned at the main flue 401, and the cooling chamber 9 and the discharging area 10 are arranged in the auxiliary flue 402; main tunnel 401 is separated from secondary tunnel 402 by a fourth material transport switch W4.
Example 14
Example 13 is repeated except that stack 4 includes main stack 401, secondary stack 402, fourth material transport switch W4; the combustion chamber 1, the heat accumulator 2 and the reduction chamber 3 are positioned above the secondary flue 402, and the cooling chamber 9 and the discharging area 10 are arranged in the secondary flue 402; main tunnel 401 is separated from secondary tunnel 402 by a fourth material transport switch W4.
Example 15
Example 14 was repeated except that the system included a plurality of sets of feed retort modules comprising the combination of the loading zone 8 and retort chamber 7, the sets of feed retort modules being arranged along the length of the flue 4.
Example 16
A method for efficiently reducing metal oxides comprises the following steps:
1) the method comprises the following steps of placing a material containing biomass and metal oxide in a reduction chamber 3, carrying out combustion heating on the material containing the biomass and the metal oxide in the reduction chamber 3 by a burner in a combustion chamber 1, simultaneously heating a heat accumulator 2 which is in the same heating space with the material, and feeding generated high-temperature flue gas into a flue 4;
2) heating the material to a certain temperature to obtain a high-temperature material, and stopping heating the material and the heat accumulator 2;
3) sealing the space between the heat accumulator 2 and the material, and pumping out the reducing gas purifying and upgrading device 6 from the bottom of the material and collecting low-quality reducing tail gas B in the material and between the heat accumulator 2 and the material;
4) the low-quality reduction tail gas B is treated by a reduction gas purification and quality improvement device 6 and is subjected to H removal2O and CO2 to obtain reducing gas A;
5) and when the content of the low-quality reduction tail gas B extracted from the bottom of the material is detected to be obviously reduced, introducing reducing gas A to the other side of the heat accumulator opposite to the material, heating the reducing gas A by the heat accumulator 2 and then introducing the reducing gas A into the reduction chamber 3, and deeply reducing the high-temperature material in the reduction chamber 3 by the reducing gas A to obtain a deep reduction material.
Example 14
Example 13 is repeated except that the method further comprises: the method comprises the following steps that 1a) materials containing biomass and metal oxides are loaded in a loading area 8, the loaded materials containing the biomass and the metal oxides are conveyed to a dry distillation chamber 7 to be pretreated, dry distillation objects generated by the dry distillation chamber 7 are conveyed to a combustion chamber 1 through a fourth pipeline L4, and the materials containing the biomass and the metal oxides and pretreated by the dry distillation chamber 7 are conveyed to a reduction chamber 3 to be treated.
Example 15
Example 14 is repeated except that the method further comprises: step 6) conveying the deep reduced material obtained after deep reduction treatment in the reduction chamber 3 to a cooling chamber 9 for cooling;
example 16
Example 15 is repeated except that in step 1), the combustion-supporting gas passes through the second heat exchanger H2, is heated by heat exchange with the flue gas in the flue 4, and is then conveyed into the combustion chamber 1, and the burner in the combustion chamber 1 combusts and heats the material containing the biomass and the metal oxide in the reduction chamber 3.
Example 17
Example 16 is repeated, but preferably, in step 5), the reducing gas a is subjected to heat exchange with flue gas in the flue 4 through the first heat exchanger H1 to raise the temperature, or the reducing gas a is subjected to heat exchange with high-temperature materials in the cooling chamber 9 to raise the temperature through the cooling chamber 9, then conveyed into the combustion chamber 1, then heated by the regenerator 2, and then introduced into the reduction chamber 3.
Claims (10)
1. A system for efficient reduction of metal oxides, the system comprising: the device comprises a combustion chamber (1), a heat accumulator (2), a reduction chamber (3), a flue (4), a material bearing ventilation platform (5), a reducing gas purification and quality improvement device (6) and a first flue gas switch (K1);
wherein the combustion chamber (1) is arranged above the reduction chamber (3), and the combustion chamber (1) is communicated with the reduction chamber (3); the heat accumulator (2) is arranged between the combustion chamber (1) and the reduction chamber (3), and the heat accumulator (2) is of a ventilating structure; the lower end of the reduction chamber (3) is communicated with the flue (4); the lower end of the reduction chamber (3) is connected with the flue (4) through a first flue gas switch (K1);
the material bearing air-permeable table (5) is arranged in the reduction chamber (3), the bottom of the material bearing air-permeable table (5) is provided with an air-permeable partition plate, and the reducing gas purification and quality improvement device (6) is communicated with the bottom of the material bearing air-permeable table (5) through an air suction opening pipeline (L1); the reducing gas duct (L2) communicates with the combustion chamber (1).
2. The system for efficient reduction of metal oxides according to claim 1, characterized in that the first outlet of the purification and upgrading device (6) for reducing gas is communicated with the combustion chamber (1) through a reducing gas pipeline (L2); preferably, the system further comprises: a first heat exchanger (H1); the first heat exchanger (H1) is arranged on the reducing gas duct (L2), and the first heat exchanger (H1) is located in the flue (4); the reducing gas exchanges heat with the flue gas in the flue (4) through a first heat exchanger (H1).
3. The efficient metal oxide reduction system according to claim 1 or 2, wherein a gas burner (101) is arranged at the top of the combustion chamber (1); a combustion-supporting gas nozzle (102) is arranged in the combustion chamber (1); preferably, the combustion-supporting gas nozzle (102) is positioned at one side of the gas burner (101); and/or
The side wall of the reduction chamber (3) is provided with a reburning nozzle (301).
4. The metal oxide high efficiency reduction system of claim 3, further comprising: a second heat exchanger (H2) and a third conduit (L3), the second heat exchanger (H2) being disposed on the third conduit (L3), and the second heat exchanger (H2) being located within the flue (4); and the combustion-supporting gas is communicated with the combustion-supporting gas nozzle (102) through a third pipeline (L3), and the combustion-supporting gas exchanges heat with the flue gas in the flue (4) through a second heat exchanger (H2).
5. The metal oxide reduction system of claim 4, further comprising: a dry distillation chamber (7); the bottom of the dry distillation chamber (7) is communicated with the flue (4); a dry distillation outlet (701) at the top of the dry distillation chamber (7) is communicated with the gas burner (101) through a fourth pipeline (L4); preferably, the system further comprises: a loading area (8), a first material transportation switch (W1); the charging area (8) is arranged at one side of the dry distillation chamber (7); the first material transportation switch (W1) is arranged between the loading area (8) and the dry distillation chamber (7).
6. The metal oxide high efficiency reduction system of claim 4 or 5, further comprising: a cooling chamber (9); the bottom of the cooling chamber (9) is communicated with a second air outlet of the reducing gas purifying and upgrading device (6) through a fifth pipeline (L5); a gas outlet at the top of the cooling chamber (9) is communicated with the combustion chamber (1) through a sixth pipeline (L6);
preferably, the flue (4) is a dual-purpose flue for flue gas conveying and material transferring; the materials which are subjected to dry distillation in the dry distillation chamber (7) are transferred into the reduction chamber (3) through the flue (4); preferably, the cooling chamber (9) is arranged on the flue (4), and the materials reduced in the reduction chamber (3) are transferred into the cooling chamber (9) through the flue (4).
7. A system for efficient reduction of metal oxides according to claim 6, characterized in that the cooling chamber (9) is arranged on the flue (4) in such a way that it further comprises: a second material transport switch (W2), a third material transport switch (W3); the second material transportation switch (W2) and the third material transportation switch (W3) are sequentially arranged on the flue (4), and a cooling chamber (9) is formed between the second material transportation switch (W2) and the third material transportation switch (W3); preferably, the system further comprises: a discharge zone (10); the discharge area (10) is arranged on the flue (4), and the discharge area (10) is separated from the cooling chamber (9) by a third material transport switch (W3).
8. The efficient metal oxide reduction system according to claim 7, comprising a plurality of groups of material reduction cooling discharging modules formed by combining the combustion chamber (1), the heat accumulator (2), the reduction chamber (3), the cooling chamber (9) and the discharging area (10), wherein the plurality of groups of material reduction cooling discharging modules are arranged along the length direction of the flue (4); preferably, the flue (4) comprises a main flue (401), a secondary flue (402) and a fourth material transportation switch (W4); the combustion chamber (1), the heat accumulator (2) and the reduction chamber (3) are positioned above the main flue (401) or the auxiliary flue (402), and the cooling chamber (9) and the discharging area (10) are arranged in the auxiliary flue (402); the main flue (401) and the auxiliary flue (402) are separated by a fourth material transportation switch (W4); and/or
The system comprises a plurality of groups of feeding dry distillation modules which are formed by combining the charging area (8) and the dry distillation chamber (7), and the plurality of groups of feeding dry distillation modules are arranged along the length direction of the flue (4).
9. A method for efficiently reducing a metal oxide, which is applied to the system for efficiently reducing a metal oxide according to any one of claims 1 to 8, comprising the steps of:
1) the method comprises the following steps of placing materials containing biomass and metal oxides in a reduction chamber (3), burning and heating the materials containing the biomass and the metal oxides in the reduction chamber (3) by a burner in a combustion chamber (1), simultaneously heating a heat accumulator (2) in the same heating space with the materials, and enabling generated high-temperature flue gas to enter a flue (4);
2) heating the material to a certain temperature to obtain a high-temperature material, and stopping heating the material and the heat accumulator (2);
3) sealing the space between the heat accumulator (2) and the material, and pumping out the reducing gas purification and quality improvement device (6) from the bottom of the material and collecting low-quality reduction tail gas B in the material and between the heat accumulator (2) and the material;
4) the low-quality reduction tail gas B is treated by a reduction gas purification and quality improvement device (6) and is subjected to H removal2O and CO2Then, obtaining reducing gas A;
5) and when the content of the low-quality reduction tail gas B extracted from the bottom of the material is detected to be obviously reduced, introducing reducing gas A to the other side of the heat accumulator opposite to the material, introducing the reducing gas A into the reduction chamber (3) after the reducing gas A is heated by the heat accumulator (2), and deeply reducing the high-temperature material in the reduction chamber (3) by the reducing gas A to obtain a deep reduction material.
10. The method for efficient reduction of metal oxide according to claim 9, further comprising:
1a) the material containing biomass and metal oxide is loaded in the loading area (8), the loaded material containing biomass and metal oxide is conveyed to the dry distillation chamber (7) for pretreatment, dry distillation products generated by the dry distillation chamber (7) are conveyed to the combustion chamber (1) through a fourth pipeline (L4), and the material containing biomass and metal oxide pretreated by the dry distillation chamber (7) is conveyed to the reduction chamber (3) for treatment; and/or
6) Deep reducing materials obtained after deep reduction treatment in the reduction chamber (3) are conveyed into a cooling chamber (9) for cooling;
preferably, in the step 1), the combustion-supporting gas passes through a second heat exchanger (H2), is subjected to heat exchange with the flue gas in the flue (4) to raise the temperature, and is then conveyed into the combustion chamber (1), and a burner in the combustion chamber (1) is used for burning and heating the material containing the biomass and the metal oxide in the reduction chamber (3);
in the step 5), the reducing gas A is subjected to heat exchange with flue gas in the flue (4) through the first heat exchanger (H1) and then heated, or the reducing gas A is subjected to heat exchange with high-temperature materials in the cooling chamber (9) through the cooling chamber (9) and then heated, and then conveyed into the combustion chamber (1), and then heated through the heat accumulator (2) and introduced into the reduction chamber (3).
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Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH01152225A (en) * | 1987-12-08 | 1989-06-14 | Kawasaki Heavy Ind Ltd | Device for drying and preheating granular ore |
| CN1036990A (en) * | 1988-03-30 | 1989-11-08 | 阿尔斯特罗姆公司 | The method of reducing and the equipment of containing metal oxide compound material |
| CN1293257A (en) * | 1999-10-15 | 2001-05-02 | 株式会社神户制钢所 | Reducing metal manufacturing equipment and manufacturing method of reducing metal |
| CN202786298U (en) * | 2012-04-16 | 2013-03-13 | 沈阳博联特熔融还原科技有限公司 | Reduction furnace equipment capable of reducing iron directly |
| CN105441620A (en) * | 2016-01-05 | 2016-03-30 | 李建涛 | Coal-based direct reduction furnace and reduction method |
| CN109652099A (en) * | 2019-01-31 | 2019-04-19 | 新疆乾海环保科技有限公司 | A kind of high temperature carbonization assembly of reduction furnace |
-
2019
- 2019-11-25 CN CN201911169300.1A patent/CN110938725B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH01152225A (en) * | 1987-12-08 | 1989-06-14 | Kawasaki Heavy Ind Ltd | Device for drying and preheating granular ore |
| CN1036990A (en) * | 1988-03-30 | 1989-11-08 | 阿尔斯特罗姆公司 | The method of reducing and the equipment of containing metal oxide compound material |
| CN1293257A (en) * | 1999-10-15 | 2001-05-02 | 株式会社神户制钢所 | Reducing metal manufacturing equipment and manufacturing method of reducing metal |
| CN202786298U (en) * | 2012-04-16 | 2013-03-13 | 沈阳博联特熔融还原科技有限公司 | Reduction furnace equipment capable of reducing iron directly |
| CN105441620A (en) * | 2016-01-05 | 2016-03-30 | 李建涛 | Coal-based direct reduction furnace and reduction method |
| CN109652099A (en) * | 2019-01-31 | 2019-04-19 | 新疆乾海环保科技有限公司 | A kind of high temperature carbonization assembly of reduction furnace |
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