CN108239700B - Coal-based fluidization reduction roasting system and roasting method thereof - Google Patents
Coal-based fluidization reduction roasting system and roasting method thereof Download PDFInfo
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- 230000009467 reduction Effects 0.000 title claims abstract description 66
- 239000003245 coal Substances 0.000 title claims abstract description 45
- 238000000034 method Methods 0.000 title claims abstract description 34
- 238000005243 fluidization Methods 0.000 title claims abstract description 14
- 239000000843 powder Substances 0.000 claims abstract description 48
- 229910052500 inorganic mineral Inorganic materials 0.000 claims abstract description 46
- 239000011707 mineral Substances 0.000 claims abstract description 46
- 239000000428 dust Substances 0.000 claims abstract description 36
- 239000007789 gas Substances 0.000 claims abstract description 34
- 239000002918 waste heat Substances 0.000 claims abstract description 30
- UGFAIRIUMAVXCW-UHFFFAOYSA-N Carbon monoxide Chemical compound [O+]#[C-] UGFAIRIUMAVXCW-UHFFFAOYSA-N 0.000 claims abstract description 29
- 239000003546 flue gas Substances 0.000 claims abstract description 29
- 238000009834 vaporization Methods 0.000 claims abstract description 20
- 230000008016 vaporization Effects 0.000 claims abstract description 20
- 238000007599 discharging Methods 0.000 claims abstract 4
- 238000006722 reduction reaction Methods 0.000 claims description 79
- 239000000463 material Substances 0.000 claims description 13
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 12
- 239000000047 product Substances 0.000 claims description 10
- 239000002994 raw material Substances 0.000 claims description 10
- 238000002309 gasification Methods 0.000 claims description 8
- 230000035484 reaction time Effects 0.000 claims description 7
- 230000000712 assembly Effects 0.000 claims description 6
- 238000000429 assembly Methods 0.000 claims description 6
- 239000007795 chemical reaction product Substances 0.000 claims description 5
- 238000001816 cooling Methods 0.000 claims description 5
- 238000011084 recovery Methods 0.000 claims description 4
- 238000003860 storage Methods 0.000 claims description 4
- 230000005855 radiation Effects 0.000 claims description 3
- 239000000725 suspension Substances 0.000 claims description 3
- 239000007921 spray Substances 0.000 claims description 2
- 239000002699 waste material Substances 0.000 claims description 2
- 239000004744 fabric Substances 0.000 claims 1
- 238000005265 energy consumption Methods 0.000 abstract description 4
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 34
- 229910052742 iron Inorganic materials 0.000 description 16
- 230000008569 process Effects 0.000 description 6
- 238000002485 combustion reaction Methods 0.000 description 5
- 229910052595 hematite Inorganic materials 0.000 description 5
- 239000011019 hematite Substances 0.000 description 5
- LIKBJVNGSGBSGK-UHFFFAOYSA-N iron(3+);oxygen(2-) Chemical compound [O-2].[O-2].[O-2].[Fe+3].[Fe+3] LIKBJVNGSGBSGK-UHFFFAOYSA-N 0.000 description 5
- 238000006243 chemical reaction Methods 0.000 description 4
- 230000005484 gravity Effects 0.000 description 4
- 238000010438 heat treatment Methods 0.000 description 4
- 230000005291 magnetic effect Effects 0.000 description 4
- 239000003034 coal gas Substances 0.000 description 3
- 238000004519 manufacturing process Methods 0.000 description 3
- 238000007254 oxidation reaction Methods 0.000 description 3
- 238000000926 separation method Methods 0.000 description 3
- CWYNVVGOOAEACU-UHFFFAOYSA-N Fe2+ Chemical compound [Fe+2] CWYNVVGOOAEACU-UHFFFAOYSA-N 0.000 description 2
- XEIPQVVAVOUIOP-UHFFFAOYSA-N [Au]=S Chemical compound [Au]=S XEIPQVVAVOUIOP-UHFFFAOYSA-N 0.000 description 2
- 230000009471 action Effects 0.000 description 2
- 239000012141 concentrate Substances 0.000 description 2
- 230000007547 defect Effects 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 description 2
- 230000001590 oxidative effect Effects 0.000 description 2
- 230000001105 regulatory effect Effects 0.000 description 2
- 229910021646 siderite Inorganic materials 0.000 description 2
- 239000007787 solid Substances 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000003749 cleanliness Effects 0.000 description 1
- 239000010883 coal ash Substances 0.000 description 1
- 125000004122 cyclic group Chemical group 0.000 description 1
- 238000009837 dry grinding Methods 0.000 description 1
- 230000005294 ferromagnetic effect Effects 0.000 description 1
- 239000010419 fine particle Substances 0.000 description 1
- 238000005188 flotation Methods 0.000 description 1
- 239000000446 fuel Substances 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 238000009533 lab test Methods 0.000 description 1
- 238000007885 magnetic separation Methods 0.000 description 1
- 238000005065 mining Methods 0.000 description 1
- 239000003345 natural gas Substances 0.000 description 1
- 230000003647 oxidation Effects 0.000 description 1
- 238000005502 peroxidation Methods 0.000 description 1
- 239000012071 phase Substances 0.000 description 1
- 239000007790 solid phase Substances 0.000 description 1
- 239000002912 waste gas Substances 0.000 description 1
Classifications
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
- C22B1/00—Preliminary treatment of ores or scrap
- C22B1/02—Roasting processes
- C22B1/10—Roasting processes in fluidised form
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P20/00—Technologies relating to chemical industry
- Y02P20/10—Process efficiency
- Y02P20/129—Energy recovery, e.g. by cogeneration, H2recovery or pressure recovery turbines
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- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Manufacturing & Machinery (AREA)
- Geochemistry & Mineralogy (AREA)
- Geology (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Environmental & Geological Engineering (AREA)
- Materials Engineering (AREA)
- Mechanical Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Manufacture And Refinement Of Metals (AREA)
- Crucibles And Fluidized-Bed Furnaces (AREA)
Abstract
The coal-based fluidization reduction roasting system comprises a coal-fired vaporization unit, a mineral powder preheating unit, a roasting unit, a waste heat utilization unit and a dust removal unit, wherein the coal-fired vaporization unit comprises a coal-fired vaporization furnace and a cyclone dust collector, the roasting unit comprises a roasting furnace, a solid-gas separator and a reduction reactor, the waste heat utilization unit comprises a heat exchanger, high-temperature flue gas generated by the coal-fired vaporization unit is not required to be cooled and is divided into two paths, one path is connected with an air inlet of the roasting furnace, and the other path is connected with an air inlet of the reduction reactor after being purified and pressurized by the cyclone dust collector; the invention also discloses a using method of the device, which comprises the steps that a feeding hole of the roasting unit is connected with a discharging hole of the mineral powder preheating unit, the discharging hole of the roasting unit is connected with a feeding hole of the waste heat utilization unit, and an exhaust hole of the mineral powder preheating unit is communicated with an air inlet of the dust removal unit. The invention has the advantages of high efficiency, high productivity, low energy consumption, low cost, wide applicable area, good product quality and the like.
Description
Technical Field
The invention relates to an ore roasting system and a roasting process method thereof, in particular to a coal-based fluidization reduction roasting system and a use method thereof.
Background
Iron ore resources in China are rich, the resource reserve reaches 850.8 hundred million tons by the end of 2015, but most of the iron ore resources are lean, fine and miscellaneous ores, and the quality is poor; the storage amount of siderite, limonite, oolitic hematite, micro-fine particle hematite and co (companion) type complex refractory iron ore resources is up to millions of tons, the conventional physical mineral separation technology cannot fully utilize the ore, the grade and recovery rate of iron concentrate are still difficult to improve though the strong (weak) magnetic flotation is carried out for many times, and most of the ore is not developed and utilized except a few mining areas. A large number of laboratory tests and industrial practices have demonstrated that magnetizing roasting is the most effective method for treating complex refractory iron ore resources.
The magnetizing roasting method of the iron ore at the present stage mainly comprises the following steps: shaft furnace roasting, rotary kiln roasting, fluidization roasting and microwave roasting. The shaft furnace roasting is used for treating lump ores with 15-75 mm, and the roasting time is long due to the coarse granularity of raw materials, and the shaft furnace roasting is only suitable for lump ores, so that the large-scale popularization and application of the shaft furnace roasting are restricted. The rotary kiln roasting is used for treating ores with the granularity of 0-25 mm, although the ore feeding granularity is smaller than that of a shaft furnace, the roasting time is 60-90 min, meanwhile, the rotary kiln roasting is easy to form rings due to the existence of fine-fraction powder ore, and the roasting process is difficult to control. The flash roasting is used for treating the powder ore with the diameter of less than 1mm, the heat transfer and mass transfer rate between the gas phase and the solid phase is 3000-4000 times greater than that of the rotary kiln, and the magnetic conversion of iron ore can be rapidly completed, but the reduction reaction time of roasting materials is only tens of seconds, so that the reduction reaction is fully carried out, the reduction temperature is generally more than 600 ℃, and particularly, the reduction time is slightly insufficient for the ore with compact oolitic hematite type structure. The microwave roasting is used for treating the ore with the size of 0-3 mm, the roasting method has low energy consumption and clean production environment, but the method is difficult to be used in the production with high yield and low added value of the iron ore due to the problems of secondary energy source, difficult large-scale device and the like.
CN201510647362, CN200610032484 and CN200720064996 all propose fluidized reduction roasting methods using coal as heat source and reducing medium, the roasting reaction process of these magnetizing roasting methods can be completed within tens of seconds, but the adjustable range of the reduction reaction time is small, and there may be insufficient reduction defect for the ore with compact structure; CN 102127635A discloses a method for oxidizing and roasting coal and gold sulfide ore in an external circulating fluidized bed reactor after dry grinding, the method mixes the coal and raw materials into a roasting furnace, the coal is burnt only to provide the temperature required by oxidizing and roasting, and the adopted reactor cannot separate coal ash, materials which have completed oxidation reaction and materials which have not completed oxidation reaction, so that the cyclic load of the materials in the reactor is larger, and because the reaction time is difficult to control accurately, the peroxidation or underoxidation phenomenon of gold sulfide ore is likely to occur, and meanwhile, the content of useful elements in roasted ore is also reduced; CN 103031432A, CN201510139825 and CN201010621731 propose fluidized oxidation (reduction) roasting methods using coal gas as heat source and reducing medium, but such roasting methods are only applicable to areas with coal gas or natural gas, and have high requirements on the cleanliness of coal gas, so that the application areas are greatly limited.
By means of technical progress, the ore fluidization roasting device and method which are more energy-saving, environment-friendly, higher in adaptability and better in mineral separation product quality are developed, limited iron ore resources in China are utilized to the greatest extent, and particularly the iron ore resources which are difficult to separate and difficult to use but lower in product quality and utilization rate are efficiently developed and utilized, so that the market share of self-produced iron ore resources in China is improved, and the method is a target pursued by those skilled in the art.
Disclosure of Invention
The invention aims to overcome the defects of the prior art and provide a coal-based fluidization reduction roasting system and a using method thereof, which have the advantages of high efficiency, high productivity, low energy consumption, low cost, wide applicable region, good product quality and the like.
In order to solve the technical problems, the technical scheme provided by the invention is as follows: the coal-based fluidization reduction roasting system comprises a coal-fired vaporization unit, a mineral powder preheating unit, a roasting unit, a waste heat utilization unit and a dust removal unit, wherein the coal-fired vaporization unit comprises a coal-fired vaporization furnace and a cyclone dust collector, the roasting unit comprises a roasting furnace, a solid-gas separator and a reduction reactor, the waste heat utilization unit comprises a heat exchanger, high-temperature flue gas generated by the coal-fired vaporization unit is not required to be cooled and is divided into two paths, one path is connected with an air inlet of the roasting furnace, and the other path is connected with an air inlet of the reduction reactor after being purified and pressurized by the cyclone dust collector; the feed inlet of the roasting unit is connected with the discharge outlet of the mineral powder preheating unit, the discharge outlet of the roasting unit is connected with the feed inlet of the waste heat utilization unit, and the exhaust outlet of the mineral powder preheating unit is communicated with the air inlet of the dust removal unit.
As a further improvement of the above technical scheme: the mineral powder preheating unit comprises 2-3 stages of cyclone preheaters, and a previous stage of cyclone preheater C 1 Is connected with the air inlet of the cyclone preheater C at the next stage 2 The exhaust ports of the cyclone preheater are connected through a riser, the tail gas of the roasting furnace is utilized for preheating mineral powder, the waste heat of the tail gas of the roasting furnace is fully utilized, the preheating is generally of level 2, the circulating preheating stage number can be adjusted according to the requirement, and the exhaust temperature of the mineral powder preheating unit is ensured to be lower than 300 ℃.
Furthermore, the discharge port of the roasting furnace is connected with the feed port of the solid-gas separator, and the discharge port of the solid-gas separator is communicated with the feed port of the reduction reactor, so that the equipment is provided with the roasting furnace only to complete the combustion heating function without providing reducing atmosphere, and the waste exhaust gas after preheating the mineral powder can be ensured to have NO residual harmful gases such as CO, NO and the like; the reduction reactor only needs to complete the reduction reaction without providing a heat source, and the reduction reaction time can be reasonably controlled by adjusting the flow of the reduction gas, thereby ensuring the independence of the operation of the roasting furnace and the reduction reactor.
Further, 3-6 layers of heat exchange assemblies are laid in the heat exchanger, a plurality of layers of heat exchange assemblies are arranged in a staggered mode, the heat exchanger is of a vertical structure, roasting ore flows downwards by gravity, a large space is reserved at the upper part of the heat exchanger, and materials flowing into the reduction reactor can be separated in the space by utilizing gravity; the upper heat radiation port of the heat exchanger is communicated with the roasting furnace, and residual reducing gas after reaction enters the roasting furnace to be combusted, so that the waste heat of the roasted ore is reasonably recovered while the fuel is fully utilized.
Further, the heat exchange component is a heat exchange plate or a heat exchange pipe, a heat exchange medium in the heat exchange component is air or water, when the heat exchange medium is water, one end of the heat exchange component is communicated with an external high-level water storage tank, and the other end of the heat exchange component is connected with an external waste heat utilization system; when the heat exchange medium is air, one end of the heat exchange component is connected with the air compressor, and the other end of the heat exchange component is connected with an external waste heat utilization system.
A method for coal-based fluidized reduction roasting, comprising the following steps:
1) Crushing raw materials: respectively crushing the ore and the fire coal, wherein the granularity of the ore is 30% -80% of 0.075mm, and the fire coal is crushed until the granularity is not more than 15mm;
2) Vaporization of coal: adding crushed coal into a coal gasification furnace, and simultaneously introducing a proper amount of water into a fluidized bed in the coal gasification furnace to generate high-temperature flue gas with reducibility;
3) Suspension preheating: the crushed ore is metered and then fed into a mineral powder preheating unit through a bucket elevator and a blast locking valve for graded preheating, so that the temperature of the preheated mineral powder is raised to 250-550 ℃, and the preheated flue gas is cooled to below 300 ℃ and then purified by a dust removal unit and discharged;
4) Fluidized reduction: the preheated mineral powder enters a roasting furnace for roasting, and then enters a reduction reactor, the high-temperature flue gas obtained in the step 2) is divided into two paths, and one path enters the roasting furnace for burning, so that a heat source is provided for a roasting system; the other path is introduced into a reduction reactor to reduce mineral powder after dust removal and pressurization;
5) And (3) waste heat utilization: the fluidized reduction product enters the heat exchanger, the heat exchange medium is not contacted with the roasting ore, the reduction product is ensured not to be oxidized secondarily, and the reaction product is cooled to 80-200 ℃ and flows out of the waste heat utilization unit through heat exchange with the heat exchange medium, so that the waste heat recovery of the reaction product is realized.
Further, the heating value of the crushed coal in the step 2) is 14000-27000 kJ/kg, and CO and H in the generated high-temperature flue gas 2 The total concentration is 10% -40%, the high-temperature flue gas is directly divided into two parts for use without cooling, and one part enters a roasting furnace for combustion, so that a heat source is provided for preheating and roasting of raw materials; the other part enters a reduction reactor after dust removal and pressurization to provide a reducing medium for raw material reduction.
Further, the dust removing unit in the step 3) comprises a high-temperature fan, a bag-type dust remover and an induced draft fan, wherein the high-temperature fan is arranged at the air outlet end of the mineral powder preheating unit, and the high-temperature fan is used for exhausting air from the mineral powder preheating unit and the roasting furnace, so that the roasting system operates under negative pressure, the pressure of the lower part of the roasting furnace is controlled to be-2000 Pa to-100 Pa, and the production environment is ensured to be clean.
Further, the materials and the flue gas in the roasting furnace in the step 4) are in a spray fluidization state, and the roasting temperature is 500-1200 ℃.
Further, the mineral powder in the reduction reactor in the step 4) is subjected to reduction reaction in a fluidized state, the reducing gas is a fluidizing medium, the consumption of the reducing gas is 1.2-2.0 times of the theoretical reduction consumption, the reduction reaction temperature is 400-1100 ℃, and the reduction reaction time is 0.5-30 min.
Compared with the prior art, the invention has the advantages that:
1. the invention adopts common fire coal to simultaneously provide heat source and reducing medium for the roasting system, which is beneficial to reducing roasting energy consumption and cost and greatly widens the applicable region of the process technology;
2. the high-temperature flue gas generated by the coal-fired gasification furnace is directly divided into two paths without cooling, one path enters the roasting furnace for combustion, and the roasting furnace only needs to complete the combustion and heating actions without providing a reducing atmosphere, so that NO residual harmful gases such as CO, NO and the like exist in the discharged tail gas after the mineral powder is preheated; the other path of the purified and pressurized gas enters the reduction reaction furnace to provide a reduction medium for the system, so that the operation independence of the roasting furnace and the reduction reactor is ensured; the flow and the components of the flue gas entering the roasting furnace and the reduction reaction furnace can be accurately regulated according to the difference of the ore properties, and the reduction roasting time is reasonably regulated;
3. according to the roasting system and the use method thereof, the multi-layer heat exchange assembly is arranged in the heat exchanger in a staggered manner, so that waste heat resources after ore roasting can be fully utilized, and further process cost is reduced;
4. the process and the equipment are suitable for magnetizing roasting of various complex refractory iron ores (such as hematite, limonite, siderite, oolitic hematite, symbiotic ores thereof and the like) and are used for magnetizing weak magnetic Fe in the ores 2 O 3 、FeCO 3 Fully converted into ferromagnetic Fe 3 O 4 ；
5. The technical scheme of the invention has the advantages of high efficiency, high productivity (large productivity per unit volume), low cost, wide applicability, good product quality and the like, and has important significance for the deep development and utilization of refractory iron ore resources in China in future.
Drawings
Fig. 1 is a schematic structural view of the present invention.
Legend description:
1. a coal-fired vaporization unit; 11. coal-fired gasification furnace; 12. a cyclone dust collector; 2. a mineral powder preheating unit; 21. a cyclone preheater; 211. cyclone preheater C of the previous stage 1 The method comprises the steps of carrying out a first treatment on the surface of the 212. Next stage cyclone preheater C 2 The method comprises the steps of carrying out a first treatment on the surface of the 3. A roasting unit; 31. a roasting furnace; 32. a solid-gas separator; 33. a reduction reactor; 4. a waste heat utilization unit; 41. a heat exchanger; 5. a dust removal unit; 51. a high temperature fan; 52. a bag-type dust collector; 53. an induced draft fan; 6. bucket elevator; 7. a locking air valve; 8. a star feeder; 9. and (3) a gas pressurizing machine.
Detailed Description
The present invention will be described more fully hereinafter with reference to the accompanying drawings, in which preferred embodiments are shown, for the purpose of illustrating the invention, but the scope of the invention is not limited to the specific embodiments shown.
As shown in fig. 1, the coal-based fluidization reduction roasting system of the embodiment comprises a coal-fired vaporization unit 1, a mineral powder preheating unit 2, a roasting unit 3, a waste heat utilization unit 4 and a dust removal unit 5, wherein the coal-fired vaporization unit 1 comprises a coal-fired vaporization furnace 11 and a cyclone dust collector 12, the roasting unit 3 comprises a roasting furnace 31, a solid-gas separator 32 and a reduction reactor 33, the waste heat utilization unit 4 comprises a heat exchanger 41, high-temperature flue gas generated by the coal-fired vaporization unit 1 is divided into two paths without cooling, one path is connected with an air inlet of the roasting furnace 31, and the other path is connected with an air inlet of the reduction reactor 33 after being purified by the cyclone dust collector 12 and pressurized by a gas pressurizing machine 9; the feed inlet of the roasting unit 3 is connected with the discharge outlet of the mineral powder preheating unit 2, the discharge outlet of the roasting unit 3 is connected with the feed inlet of the waste heat utilization unit 4, and the exhaust outlet of the mineral powder preheating unit 2 is communicated with the air inlet of the dust removal unit 5.
In this embodiment, the ore powder preheating unit 2 includes a two-stage cyclone preheater 21, a higher-stage cyclone preheater C 1 211 air inlet and next stage cyclone preheater C 2 The exhaust ports of 212 are connected by a riser.
Cyclone preheater C of the previous stage 1 211 air inlet pipe is connected to the cyclone preheater C at the next stage through a riser 2 212, the feed opening of the bucket elevator 6 is connected with the upper cyclone preheater C through a pipeline 1 211 is connected with the upper cyclone preheater C 1 211, and the discharge hole at the bottom of the cyclone preheater C at the next stage after passing through a pipeline and a locking air valve 7 2 212, the upper cyclone preheater C 1 211 is communicated with an air inlet of a bag-type dust collector 52 of the dust removing unit through a high-temperature fan 51 and a pipeline, the air outlet of the bag-type dust collector 52 is communicated with an air inlet of a draught fan 53 through a pipeline, and the air outlet of the draught fan 53 is connected with an external chimney through a pipeline.
In this embodiment, the inlet of the roasting furnace 31 is connected to the cyclone preheater C at the next stage through a pipe 2 212, the discharge port of the roasting furnace 31 is connected with the feed port of the solid-gas separator 32, and the exhaust port of the solid-gas separator 32 is connected with the cyclone preheater C of the next stage through a riser tube 2 212, and the discharge port of the solid-gas separator 32 is communicated with the feed port of the reduction reactor 33.
In the embodiment, five layers of heat exchange assemblies are paved in the heat exchanger 41, the multi-layer heat exchange assemblies are arranged in a staggered mode, and the heat exchanger 41 is of a vertical structure; the upper heat radiation port of the heat exchanger 41 is communicated with the roasting furnace 31, and the discharge port of the heat exchanger 41 is connected with the feed port of the star feeder 8 through a pipeline, so that the roasted ore is discharged conveniently.
In this embodiment, the heat exchange component is a heat exchange plate or a heat exchange tube, the heat exchange medium in the heat exchange component is water, one end of the heat exchange component is communicated with an external high-level water storage tank, and the other end of the heat exchange component is connected with an external waste heat utilization system.
A method for coal-based fluidized reduction roasting, comprising the following steps:
1) Crushing raw materials: respectively crushing ore and fire coal, wherein the granularity of the ore is 30% -80% of the granularity of the ore is less than 0.075mm, the fire coal is crushed until the granularity is not more than 15mm, and the crushed ore and fire coal are respectively stored in a mineral powder raw material bin and a fire coal raw material bin;
2) Vaporization of coal: adding crushed coal into the coal gasification furnace 11, and simultaneously introducing a proper amount of water into a fluidized bed in the coal gasification furnace 11 to generate high-temperature flue gas with reducibility;
3) Suspension preheating: the mineral powder in the raw material bin is metered and then fed into the cyclone preheater C at the upper stage through the bucket elevator 6 and the air locking valve 7 1 211 to raise the temperature of the material to 250-300 ℃ and then enter the cyclone preheater C at the next stage 2 212, further preheating, and after the temperature of the tail gas is reduced to about 230 ℃, entering a dust removal unit 5; through the cyclone preheater C of the previous stage 1 211 the mineral powder after preheating enters the cyclone preheater C of the next stage again 2 212 and the exhaust gas discharged from the roasting furnace 31 are subjected to heat exchange, so that the temperature of the mineral powder is increased to 500-550 ℃ and then enters the roasting furnace 31, and the mineral powder enters a cyclone preheater C at the next stage 2 The temperature of the waste gas discharged from the 212 exhaust ports is reduced to 400-450 ℃ and then enters the upper cyclone preheater C 1 211 performs heat exchange with mineral powder;
4) Fluidized reduction: the preheated mineral powder enters a roasting furnace 31 for roasting, then enters a reduction reactor 33, and the high-temperature flue gas obtained in the step 2) is divided into two paths, wherein one path enters the roasting furnace 31 for burning, so that a heat source is provided for a roasting system; the other path is introduced into the reduction reactor 33 after dust removal and pressurization to reduce mineral powder;
5) And (3) waste heat utilization: the fluidized reduction product enters the upper part of the heat exchanger 41, and the gravity is utilized to carry out gas-solid separation on the material flowing into the reduction reactor 33 in the space; the separated flue gas enters a roasting furnace 31 to be burnt, so that a heat source is provided for a roasting system; the solid roasting product enters a material waste heat utilization area at the lower part of the heat exchanger 41 under the action of gravity to recycle waste heat; the material waste heat utilization area is provided with plate-shaped heat exchange components in a staggered manner, water is introduced into the heat exchange components to serve as a heat exchange medium, and the high-temperature material is subjected to heat exchange with the heat exchange medium, so that reaction products are cooled to 150 ℃ and then sent out of the reaction device, and fluidization reduction roasting treatment is completed.
In the embodiment, the heating value of the crushed coal in the step 2) is 14000-27000 kJ/kg, and CO and H in the generated high-temperature flue gas 2 The total concentration is 10% -40%, the high-temperature flue gas is directly divided into two paths through an automatic control valve without cooling, and the flow rates of the two paths of flue gas are accurately controlled, so that the amount of flue gas entering the roasting furnace 31 for combustion accounts for 70% -80% of the total amount of the flue gas, and the amount of gas introduced into the reduction reactor 33 after dust removal and pressurization accounts for 20% -30% of the total amount of the flue gas; the temperature of the flue gas generated after the gas is burnt in the roasting furnace 31 is 700-750 ℃, and the roasted mineral powder is heated to 550-600 ℃ and then flows into the reduction reactor 33 for further reduction reaction.
In this embodiment, the dust removing unit 5 in step 3) includes a high temperature fan 51, a bag-type dust remover 52 and a draught fan 53, the high temperature fan 51 is disposed at the air outlet end of the mineral powder preheating unit 2, the high temperature fan 51 is used for exhausting air from the mineral powder preheating unit 2 and the roasting furnace 31, so that the roasting system operates under negative pressure, and the pressure at the lower part of the roasting furnace 31 is controlled to be-2000 Pa to-100 Pa.
In this embodiment, the material and the flue gas in the roasting furnace 31 in step 4) are in a fluidized state, and the roasting temperature is 500-1200 ℃.
In this embodiment, the ore powder in the reduction reactor 33 in step 4) undergoes a reduction reaction in a fluidized state, and the reducing gas is a fluidizing medium, and the amount of the reducing gas is 1.2 to 2.0 times of the theoretical reduction amount, the reduction reaction temperature is 400 to 1100 ℃, and the reduction reaction time is 0.5 to 30 minutes.
For complex refractory iron ore with TFe grade of 32.54 percent, the coal-based fluidization reduction roasting process is adopted to treat, the magnetic susceptibility of a roasted product is more than or equal to 95 percent, and the roasted ore is not ground and is subjected to one-coarse two-fine three times of weak magnetic separation to obtain the grading index with iron concentrate grade more than or equal to 60 percent and iron recovery rate more than or equal to 88 percent.
Claims (7)
1. A coal-based fluidization reduction roasting system is characterized in that: comprises a coal-fired vaporization unit (1), a mineral powder preheating unit (2), a roasting unit (3) and waste heatThe device comprises a utilization unit (4) and a dust removal unit (5), wherein the coal-fired vaporization unit (1) comprises a coal-fired vaporization furnace (11) and a cyclone dust collector (12), the roasting unit (3) comprises a roasting furnace (31), a solid-gas separator (32) and a reduction reactor (33), the waste heat utilization unit (4) comprises a heat exchanger (41), high-temperature flue gas generated by the coal-fired vaporization unit (1) is not required to be cooled and divided into two paths, one path is connected with an air inlet of the roasting furnace (31), and the other path is connected with an air inlet of the reduction reactor (33) after being purified and pressurized by the cyclone dust collector (12); the feeding hole of the roasting unit (3) is connected with the discharging hole of the mineral powder preheating unit (2), the discharging hole of the roasting unit (3) is connected with the feeding hole of the waste heat utilization unit (4), and the air outlet of the mineral powder preheating unit (2) is communicated with the air inlet of the dust removal unit (5); the mineral powder preheating unit (2) comprises 2-3-stage cyclone preheaters (21), and a previous-stage cyclone preheater C 1 (211) Is connected with the air inlet of the cyclone preheater C at the next stage 2 (212) The exhaust ports of the two are connected through a lifting pipe; the discharge port of the roasting furnace (31) is connected with the feed port of the solid-gas separator (32), and the discharge port of the solid-gas separator (32) is communicated with the feed port of the reduction reactor (33); 3-6 layers of heat exchange assemblies are paved in the heat exchanger (41), a plurality of layers of heat exchange assemblies are arranged in a staggered mode, and the heat exchanger (41) is of a vertical structure; the upper heat radiation port of the heat exchanger (41) is communicated with the roasting furnace (31).
2. The coal-based fluidized reduction roasting system according to claim 1, wherein: the heat exchange component is a heat exchange plate or a heat exchange pipe, a heat exchange medium in the heat exchange component is air or water, when the heat exchange medium is water, one end of the heat exchange component is communicated with an external high-level water storage tank, and the other end of the heat exchange component is connected with an external waste heat utilization system; when the heat exchange medium is air, one end of the heat exchange component is connected with the air compressor, and the other end of the heat exchange component is connected with an external waste heat utilization system.
3. A method of coal-based fluidized reduction roasting using the system of claim 1 or 2, comprising the steps of:
1) Crushing raw materials: respectively crushing the ore and the fire coal, wherein the granularity of the ore is 30% -80% of 0.075mm, and the fire coal is crushed until the granularity is not more than 15mm;
2) Vaporization of coal: adding crushed coal into a coal gasification furnace (11), and simultaneously introducing a proper amount of water into a fluidized bed in the coal gasification furnace (11) to generate high-temperature flue gas with reducibility;
3) Suspension preheating: the crushed ore is metered and then fed into a mineral powder preheating unit (2) through a bucket elevator (6) and a locking air valve (7) for graded preheating, so that the temperature of the preheated mineral powder is raised to 250-550 ℃, and the preheated flue gas is cooled to below 300 ℃ and is purified by a dust removal unit (5) and then discharged;
4) Fluidized reduction: the preheated mineral powder enters a roasting furnace (31) for roasting, then enters a reduction reactor (33), the high-temperature flue gas obtained in the step 2) is divided into two paths, and one path enters the roasting furnace (31) for burning, so that a heat source is provided for a roasting system; the other path is introduced into a reduction reactor (33) to reduce mineral powder after dust removal and pressurization;
5) And (3) waste heat utilization: the fluidized reduction product enters a heat exchanger (41), the heat exchange medium is not contacted with the roasting ore, and the reaction product is cooled to 80-200 ℃ and flows out of a waste heat utilization unit (4) through heat exchange with the heat exchange medium, so that the waste heat recovery of the reaction product is realized.
4. A method of coal-based fluidized reduction roasting according to claim 3, wherein: the calorific value of the crushed coal in the step 2) is 14000-27000 kJ/kg, and CO and H in the generated high-temperature flue gas 2 The total concentration is 10% -40%, and the high-temperature flue gas is directly divided into two parts for use without cooling.
5. A method of coal-based fluidized reduction roasting according to claim 3, wherein: the dust removing unit (5) in the step 3) comprises a high-temperature fan (51), a cloth bag dust remover (52) and a draught fan (53), wherein the high-temperature fan (51) is arranged at the air outlet end of the mineral powder preheating unit (2), the high-temperature fan (51) is used for exhausting air from the mineral powder preheating unit (2) and the roasting furnace (31), so that the roasting system operates under negative pressure, and the pressure at the lower part of the roasting furnace (31) is controlled to be-2000 Pa to-100 Pa.
6. A method of coal-based fluidized reduction roasting according to claim 3, wherein: the materials and the flue gas in the roasting furnace (31) in the step 4) are in a spray fluidization state, and the roasting temperature is 500-1200 ℃.
7. A method of coal-based fluidized reduction roasting according to claim 3, wherein: the mineral powder in the reduction reactor (33) in the step 4) is subjected to reduction reaction in a fluidized state, the reducing gas is a fluidizing medium, the consumption of the reducing gas is 1.2-2.0 times of the theoretical reduction consumption, the reduction reaction temperature is 400-1100 ℃, and the reduction reaction time is 0.5-30 min.
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Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2619806A1 (en) * | 1987-08-25 | 1989-03-03 | Cle | Process and system for producing clinker and product thus obtained |
| CN101191149A (en) * | 2006-11-22 | 2008-06-04 | 中国科学院过程工程研究所 | Coal gasification-pore iron ore magnetic roasting coupling technique and device |
| CN102560091A (en) * | 2012-02-24 | 2012-07-11 | 湖南长拓高科冶金有限公司 | Preparation method and preparation device for weak reducing gas and flash-magnetization iron ore roasting system |
| CN103031432A (en) * | 2011-09-30 | 2013-04-10 | 中国科学院过程工程研究所 | System for fluidized oxidizing/reducing roasting modification of titaniferous iron concentrate and roasting process |
| CN104131158A (en) * | 2014-07-18 | 2014-11-05 | 黄石市新瑞环保科技有限公司 | Laminated circulating fluidized bed gasification-magnetization baking device and baking process |
| CN204125496U (en) * | 2014-07-18 | 2015-01-28 | 黄石市新瑞环保科技有限公司 | A kind of folded connection formula circulating fluidized bed gasification-magnetizing roasting device |
| CN205856558U (en) * | 2016-07-15 | 2017-01-04 | 甘肃酒钢集团宏兴钢铁股份有限公司 | A kind of refractory iron ore stone powder magnetizing roast system |
| CN207973788U (en) * | 2018-03-07 | 2018-10-16 | 长沙矿冶研究院有限责任公司 | A kind of coal base fluidization reduction roasting system |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103725819B (en) * | 2013-12-31 | 2015-06-03 | 中国科学院过程工程研究所 | Iron ore powder fluidized reduction system and method |
-
2018
- 2018-03-07 CN CN201810188118.XA patent/CN108239700B/en active Active
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2619806A1 (en) * | 1987-08-25 | 1989-03-03 | Cle | Process and system for producing clinker and product thus obtained |
| CN101191149A (en) * | 2006-11-22 | 2008-06-04 | 中国科学院过程工程研究所 | Coal gasification-pore iron ore magnetic roasting coupling technique and device |
| CN103031432A (en) * | 2011-09-30 | 2013-04-10 | 中国科学院过程工程研究所 | System for fluidized oxidizing/reducing roasting modification of titaniferous iron concentrate and roasting process |
| CN102560091A (en) * | 2012-02-24 | 2012-07-11 | 湖南长拓高科冶金有限公司 | Preparation method and preparation device for weak reducing gas and flash-magnetization iron ore roasting system |
| CN104131158A (en) * | 2014-07-18 | 2014-11-05 | 黄石市新瑞环保科技有限公司 | Laminated circulating fluidized bed gasification-magnetization baking device and baking process |
| CN204125496U (en) * | 2014-07-18 | 2015-01-28 | 黄石市新瑞环保科技有限公司 | A kind of folded connection formula circulating fluidized bed gasification-magnetizing roasting device |
| CN205856558U (en) * | 2016-07-15 | 2017-01-04 | 甘肃酒钢集团宏兴钢铁股份有限公司 | A kind of refractory iron ore stone powder magnetizing roast system |
| CN207973788U (en) * | 2018-03-07 | 2018-10-16 | 长沙矿冶研究院有限责任公司 | A kind of coal base fluidization reduction roasting system |
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