CN1069324A - The oxy-fuel combustion device and the using method of melting waste steel - Google Patents
The oxy-fuel combustion device and the using method of melting waste steel Download PDFInfo
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- CN1069324A CN1069324A CN 91104867 CN91104867A CN1069324A CN 1069324 A CN1069324 A CN 1069324A CN 91104867 CN91104867 CN 91104867 CN 91104867 A CN91104867 A CN 91104867A CN 1069324 A CN1069324 A CN 1069324A
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Abstract
The present invention is used to heat the burner with melting waste steel, its design feature offer for the center fuel tube wall and intercommunicating pore pipe, central tube and the inner sleeve of interior cover oxygen pipe between be provided with the swirl-flow devices of outer ring set and overcoat oxygen pipe.By regulating its section ratio, regulate the ratio between pre-mixing oxygen, eddy flow oxygen and dc loop-current oxygen, so that the control oxygen fuel mixes and flame rigidity.Eddy flow and dc loop-current oxygen ratio are adjusted to 2: 8-6: 4.
Description
The present invention is used for steelmaking process, the heating of furnace charge (comprising steel scrap, the pig iron) and the burner and the using method thereof of fusing.
Electric arc furnaces is the modernization steel-making device based on steel scrap, adopts three electrode power supply heat fused steel scraps, belongs to the heat point source heat supply, causes the temperature field in furnace skewness, occurs the hot-zone and the cold-zone of heating in stove.Therefore, time melting stage is long, and power consumption accounts for more than 60% of full stove power consumption.Along with electric arc furnaces ultra high powerization and correlation technique thereof are used and development, especially provide auxiliary thermal source with the oxy-fuel combustion device to the electric arc furnaces cold-zone, the development of furnace outer refining technology, promote that the electric arc furnace smelting power consumption is reduced significantly, the development of electric arc furnaces presents its great vitality, it can produce steel alloy and special steel, also can produce ordinary steel.Electric arc furnaces self is converted into the equipment of melting waste steel gradually by the smelting equipment of special steel, reduce the melting stage indicator of power consumption, and shortening the heat more seems important.Wherein the oxy-fuel combustion device then has been one of important measures of saving energy of electric arc furnace.
Owing to adopt the electric arc furnaces correlation technique, since nineteen sixty, external power consumption is reduced to 400Kwh/t from 630Kwh/t, tapping=tapping the time drops to 70min from 180min, adopt the oxy-fuel combustion device to provide auxiliary heat to interelectrode cold-zone, this regional scrap melting and other hot-zone scrap melting are reached synchronously, thereby shortened fusing time effectively and reduced power consumption.Abroad, usual earlier adopts oxygen-oil or its power of oxygen-gas burner to be about 1/4=1/2 of furnace transformer power, energy-conservation is 10%, the 15-25% that boosts productivity, generally reducing power consumption is 40-70Kwh/t, the structure majority of its burner is the burner of bushing type or attached swirl vane, Japan and China all develop oxygen-powdered coal burner since the seventies, provide auxiliary thermal source to the electric arc furnaces cold-zone, its energy-saving and production-increase effect and oxygen-oil, the burner of oxygen-combustion gas is close.
Powdered coal burner important techniques key is the mixing and the igniting of oxygen and fine coal, most mixing of adopting swirl-flow devices or utilizing multiply circulation bushing type burner acceleration oxygen and fine coal, and mixability is decided by the size of recirculating zone.Because adopt swirl-flow devices then to influence the axial spread speed of flame, bushing type burner mixability is poor, thereby reduces its efficiency of heating surface.In order to improve the mixing of oxygen and fine coal, increase the axial spread speed and the rigidity of flame.Flame with high temperature and high speed, high rigidity heats and melting waste steel, further improves burn-off rate and heat utilization efficiency.
The present invention seeks to the shortcoming that the oxygen-powdered coal burner at existing bushing type or spiral-flow type exists, taking directly to mix in part oxygen and the fine coal carrier pipe is oxygen and fine coal mixed once, utilize the oxygen of oxygen eddy flow and the secondary of fine coal to mix, and fully the mixing and measure such as completing combustion of oxygen direct current annular jet and unburnt combustible, select the combine oxygen-powdered coal burner of structure of mixed in oxygen and the fine coal, eddy flow and dc loop-current oxygen jet.To reach the mixability that improves oxygen and fine coal, improve flame temperature, improve the combustion rate of fine coal, increase flame jet intensity, improve heat exchanger effectiveness, so that quicken steel scrap heating and burn-off rate, further reduce the electric arc furnace smelting power consumption, shorten the heat, boost productivity.
The structure of the oxygen-powdered coal burner of heating of the present invention and melting waste steel (seeing Fig. 1,2,3).Comprise center conveying fine coal pipe (1), the delivery of oxygen pipe is divided into inner sleeve (2), outer tube (3), the swirl-flow devices (4) of outer sleeve is installed on the fine coal pipe port of export outer wall of center in the shower nozzle, its swirl-flow devices is swirl vane, tangential vane, guiding gutter etc., be placed between central tube and the inner sleeve, outer tube is the oxygen DC tube, is eddy flow and direct current oxygen spray pipe in the shower nozzle.Its section ratio is selected according to the eddy flow and the direct current ratio of oxygen flow.Three layers of telescopic water-cooling apparatus (5) of protection oxygen-powdered coal burner, water inlet (6), delivery port (7), eddy flow oxygen intake (8), direct current oxygen intake (9), fine coal inlet (10).
Swirl-flow devices of the present invention is placed in the port of export of center fine coal pipe, see Fig. 2, swirl-flow devices (11), the outer sleeve of swirl-flow devices (12), it is that oxygen jet in the oxygen swirl flow nozzle in the inner sleeve is divided into rotating jet and dc loop-current, its section ratio is to be undertaken by the relative position of regulating center fine coal pipe swirl-flow devices and inner sleeve oxygen nozzle end, so that regulate the eddy flow amount of oxygen flow and the ratio of DC quantity, the adjusting ratio of its eddy flow and direct current oxygen amount is 2: 8-6: 4.Carry the fine coal tube wall to offer the intercommunicating pore pipe (13) that overlaps oxygen pipe and fine coal pipe in the connection at the center, its equivalent diameter is 0.001-0。010m, it distributes along the circumference and the axial distribution of carrying the fine coal tube wall, can be according to the pressure reduction between the carrier gas of oxygen pressure and conveying fine coal, so that determine to offer the area of intercommunicating pore pipe, select suitable equivalent diameter and perforate quantity determining the oxygen amount of input fine coal carrier pipe, the intercommunicating pore pipe is along carrying around the fine coal tube wall and axial distribution.
The present invention offers the intercommunicating pore pipe along fine coal carrier wall circumference, oxygen content is that 30-60% is a foundation to its perforated area in its carrier gas to control, and the spacing of the intercommunicating pore of axially offering is a 0.01-0.2 rice, according to perforated area, determine opening diameter and quantity, and determine its distribution.According to the content of fine coal fugitive constituent, select to determine to offer the axial aperture position of intercommunicating pore pipe, i.e. perforate is apart from the axial distance of the shower nozzle port of export.Its fine coal volatile matter is high more, and it is short more apart from the axial distance of the port of export then to offer intercommunicating pore, and the fine coal fugitive constituent is low more, and its axial distance is long more.
The present invention can regulate the conveying fine coal pipe of swirl-flow devices of outer sleeve and the oxygen inner sleeve position that axially relatively moves, so that change oxygen eddy flow, oxygen direct current and feed the ratio of oxygen flow in the fine coal carrier pipe, realizes that flame regulates.
Oxygen of the present invention-powdered coal burner rely on himself at a high speed Oxygen Flow or air to flow to promoting the circulation of qi cold, and, reasonably select the fine coal spouting velocity, the swirl strength of the Oxygen Flow of eddy flow, axial velocity, and the muzzle velocity of oxygen dc loop-current in the outer tube, be 0.03-0.3m to guarantee the flame root apart from the suitable distance of shower nozzle outlet, this is the oxygen-powdered coal burner that relies on self air cooling.The electric arc furnace wall is under the condition of water-cooled dross furnace wall, adopts the oxygen-powdered coal burner of self air cooling.If the electric arc furnace wall is a refractory material,, can adopt cooling jacket for protection refractory material furnace wall; its structure is three layers of sleeve pipe; see accompanying drawing 3, cooling jacket placed in the duct of burner of furnace wall that its outlet is designed to be contracted to earlier aditus laryngis; the outlet form (14) of the similar burner of further expansion; outer tube (15), middle sleeve (16), inner sleeve (17); outlet pipe (18), oral siphon (19).Oxygen-powdered coal burner is placed in the cooling jacket, and burner moves axially along water jacket and regulates its axial distance, to adjust the burner outlet position.Burner can be fixed or telescopic, and in the former smelting process, burner is fixed in the water jacket all the time, the latter, and according to smelting requirements, oxygen-powdered coal burner can advance or withdraw from.
The embodiment 1 of oxygen-powdered coal burner of the present invention, its structure is seen Fig. 4, carry on the fine coal pipe (20) at the center, the swirl-flow devices (21) of outer sleeve is installed, oxygen outer tube (22), Oxygen Flow forms eddy flow by swirl-flow devices, utilizes the axial location of mobile fine coal carrier pipe to change the ratio of the circumferential weld area between oxygen eddy flow discharge area and swirl-flow devices outer sleeve and oxygen internal surface of sleeve pipe; To adjust the ratio of its eddy flow oxygen amount and direct current oxygen amount.Can be adjusted to the ratio 1: 4 of oxygen eddy flow amount and DC quantity by oxygen wheel stream, this structure can realize that flame regulates, and guarantees that the secondary of oxygen and fine coal mixes, and the direct current Oxygen Flow is finished the completing combustion of fuel and guaranteed flame rigidity.This burner is used for about 27 tons-30 tons electric arc furnaces of charge weight, transformer efficiency 7000-9000KVA, oxygen-powdered coal burner general power 2400-4000KW, three oxygen-powdered coal burners place on the furnace wall, to the heat supply of electric arc furnaces cold-zone, its melting stage power consumption reduction 50-100Kwh/t, time melting stage shortens 20-30min, and productivity ratio improves 8%.
The embodiment of the invention 2, its structure is seen accompanying drawing 1, oxygen-powdered coal burner comprises fine coal carrier pipe, oxygen inner sleeve and outer tube, the fine coal carrier pipe is set up the swirl-flow devices of outer sleeve, and offer the intercommunicating pore diameter 0.002-0.003 rice of carrying the fine coal tube wall, number of aperture is 20-40, and its perforated area is the 40-100% of carrier pipe outlet, and oxygen content is 30-60% in the carrier gas of raising conveying fine coal.Utilization moves axially carries the fine coal pipe to regulate eddy flow oxygen amount and direct current oxygen amount by interior cover oxygen pipe 5: 1, simultaneously, utilizes eddy flow oxygen and direct current oxygen valve, the ratio of adjusting eddy flow oxygen amount and outer tube direct current oxygen amount, and its total adjusting ratio is 2: 8-6: 4.Oxygen-powdered coal burner of the present invention is used for the electric arc furnaces of 38 tons of charge weights, transformer efficiency 9000-12000KVA, the oxy coal burner general power is 2600-5000KW, adopt this oxygen-powdered coal burner to flux, its time melting stage shortens 30min, power consumption reduces 80-100Kwh/t, and its full stove power consumption reaches the good index of 450Kwh/t, and productivity ratio can improve 10-15%.
Oxygen-powdered coal burner of the present invention is simple in structure, by regulating eddy flow and direct current oxygen outlet cross section or flow control valve, realize the perforated area of the ratio of eddy flow oxygen flow and direct current oxygen flow by fine coal carrier wall intercommunicating pore, oxygen and carrier gas pressure reduction are regulated the oxygen content of carrier gas.Like this, oxygen and fine coal are evenly mixed, help igniting and smooth combustion rapidly, utilize direct current oxygen jet to finish completing combustion, and enhancing flame transmission speed and jet intensity, strengthen flame rigidity, improve convection current, radiant heat transfer efficient, improve the combustion rate of fuel, quicken steel scrap heating and fusion process, further shorten fusing time, reduce power consumption.
The present invention need not outer thermal source, utilize the residual heat high-temperature in the electric arc furnaces can realize normal ignition, light a fire behind the fettling and before the charging, also can after charging, light a fire smoothly, in case of necessity, utilize starting the arc igniting, oxygen and anthracite are 3-5 minute normal ignitions after energising, anthracite and bituminous coal mixture are the 1-3 minute normal ignitions in energising back, and bituminous coal and coke mixture then are 3-8 minute normal ignitions after the energising, realize normal ignition immediately after oxygen and bituminous coal are then feeded.
The present invention can be under electric arc furnaces normal power supply condition, introduce oxygen-powdered coal burner simultaneously and provide heat heating and melting waste steel to the cold-zone, suitably adjust the technological parameter of oxygen-pulverized coal friring, can obtain the effect of fluxing preferably, shorten the heat, reduce power consumption, under cold situation, normal ignition utilizes heating of oxygen coal combustion heat and melting waste steel, pulverized coal injection and the oxygen time of fluxing were controlled at 45-60 minute, energising utilizes the electric arc heated steel scrap again, can reduce power consumption, up 100-150Kwh/t significantly.The present invention utilizes the heat supply of oxygen powdered coal burner, is generally 40-90 minute, and fusing time is 70-120 minute, and power consumption reduces 50-120Kwh/t.
The technological parameter of oxygen-powdered coal burner of the present invention, coal supply amount are that 0.15-0.50 kilogram/ton divides, and oxygen-supplying amount 0.2-1.5 marks rice
3/ ton divides, and the ratio of the carbon content in its oxygen and the fine coal is 2-3.5, adjusts ratio between its oxygen and charcoal according to the fusing process.Best coal supply amount is that 0.15-0.35 kilogram/ton divides, and best oxygen-supplying amount is a 0.3-1.2 mark rice
3/ ton divides.
It is bituminous coal that the present invention uses fuel, anthracite, and fine powders such as coke, and composition thereof, also can use gas and liquid fuel etc.Can be used for the charging stock for electric furnace preheating, melting stage the technology of fluxing, also can be used for the complete coal-fired energy saver of open hearth heating or melting waste steel or EOF, oxygen-powdered coal burner can place the electric arc furnace wall to place the interior cold-zone of electric arc furnaces, or place electric arc furnaces bell top, simultaneously, can place stove gate.
Oxygen-powdered coal burner of the present invention is simple in structure, is convenient to regulate, and easy operating, small investment is the important conservation measures of electric arc furnaces, can reduce power consumption significantly, shortens melting stage, boosts productivity and reduces cost, its pay back period is generally 1-1.5.
Claims (9)
1, oxygen-the powdered coal burner of a kind of heating and melting waste steel, comprise and carry the fine coal pipe, the delivery of oxygen pipe, oxygen spray pipe is set up swirl-flow devices in the shower nozzle, it is characterized in that the delivery of oxygen pipe comprises inner sleeve and outer tube, the swirl vane of outer sleeve is installed between the inner sleeve of shower nozzle and the conveying fine coal central tube, tangential vane or guiding gutter, the intercommunicating pore pipe of cover oxygen pipe and fine coal pipe in the fine coal carrier wall is offered and is communicated with, its equivalent diameter is 0.001-0.010m, circumference and axial distribution that it distributes and changes the fine coal tube wall along defeated, outer tube is the delivering oxygen DC tube, burner tip comprises oxygen eddy flow and direct current jet pipe, and its section ratio is selected according to the eddy flow and the direct current ratio of oxygen flow, and its eddy flow and DC adjustment ratio are 2: 8-6: 4.
2, according to the described oxygen-powdered coal burner of claim 1, it is characterized in that offering intercommunicating pore along fine coal carrier wall circumference, the intercommunicating pore perforated area is 30-60% to control its carrier gas oxygen content, the spacing of the intercommunicating pore of axially offering is a 0.01-0.2 rice, according to the volatile matter content chosen axis of fine coal to position of opening, apart from the axial distance of shower nozzle outlet.
3, according to the described oxygen-powdered coal burner of claim 1, it is characterized in that protecting the cooling jacket of fire proof material of furnace lining, be fixed in the burner putting hole of body of heater, burner relies on self air cooling or places in the cooling jacket.
4, according to the described oxygen-powdered coal burner of claim 1, it is characterized in that the conveying fine coal pipe of the attached swirl-flow devices of regulating outer sleeve and the oxygen inner sleeve position that axially relatively moves, so that change the oxygen eddy flow, oxygen flow ratio in oxygen direct current and the feeding fine coal carrier pipe, realization flame is regulated.
5, according to the using method of the described oxygen-powdered coal burner of claim 1, it is characterized in that utilizing the electric arc furnaces waste heat, before charging, after can light a fire smooth combustion smoothly.Its technological parameter is that coal supply amount 0.15-0.50 kilogram/ton divides, and oxygen-supplying amount 0.2-1.5 marks rice
3/ ton divides.The ratio of the carbon content in its oxygen and the fine coal is 2-3.5, adjusts ratio between its oxygen and charcoal according to the fusing process.
6, according to the using method of the described oxygen-powdered coal burner of claim 5, it is characterized in that the electric arc furnaces fusing early stage can be only with burner heat supply 40-60 minute, energising is heated simultaneously until fusing again.
7, burner using method according to claim 5 is characterized in that best coal supply amount is that 0.15-0.35 kilogram/ton divides, and best oxygen-supplying amount is a 0.3-1.2 mark rice
3/ ton divides.
8, according to claim 1,5 described powdered coal burner and usings method, it is characterized in that embodiment 1 comprises the fine coal carrier pipe, the swirl-flow devices of outer sleeve is installed, the oxygen outer tube, Oxygen Flow forms eddy flow by swirl-flow devices, utilize the axial location of mobile fine coal carrier pipe to change the ratio of the circumferential weld area between Oxygen Flow discharge area and swirl-flow devices outer sleeve and oxygen internal surface of sleeve pipe, to adjust the ratio of its eddy flow oxygen amount and direct current oxygen amount.The ratio that can be adjusted to oxygen eddy flow amount and DC quantity by oxygen wheel stream is 1: 4.
9, according to claim 1,5 described powdered coal burner and usings method, it is characterized in that embodiment 2 comprises the fine coal carrier pipe, oxygen inner sleeve and outer tube, the fine coal carrier pipe is set up the swirl-flow devices of outer sleeve, and offer the intercommunicating pore diameter 0.002-0.003m that carries the fine coal tube wall, number of aperture 20-40, its perforated area is carrier pipe outlet 40-100%, the oxygen content that improves in the fine coal carrier gas is 30-60%, utilization moves axially that to carry the fine coal pipe to regulate eddy flow oxygen amount be 5: 1 with direct current oxygen amount by inner sleeve, simultaneously, utilize eddy flow oxygen and direct current oxygen valve, regulate the ratio of eddy flow oxygen amount and outer tube direct current oxygen amount, its total adjusting ratio is 2: 8-6: 4.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 91104867 CN1069324A (en) | 1991-07-22 | 1991-07-22 | The oxy-fuel combustion device and the using method of melting waste steel |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 91104867 CN1069324A (en) | 1991-07-22 | 1991-07-22 | The oxy-fuel combustion device and the using method of melting waste steel |
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| CN1069324A true CN1069324A (en) | 1993-02-24 |
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| CN 91104867 Pending CN1069324A (en) | 1991-07-22 | 1991-07-22 | The oxy-fuel combustion device and the using method of melting waste steel |
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Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101280917B (en) * | 2008-05-13 | 2010-04-14 | 吕伟鹏 | Coal gas, coal fines and oxygen-enriched mixed combustion device |
| CN101451714B (en) * | 2007-11-30 | 2012-08-22 | 皮亚尔取暖工业总集团 | Double flow annular pipe and combustor including the double flow annular pipe |
| CN103443541A (en) * | 2011-04-05 | 2013-12-11 | 气体产品与化学公司 | Oxy-fuel furnace and method of heating material in an oxy-fuel furnace |
| CN107355783A (en) * | 2016-05-10 | 2017-11-17 | 中冶长天国际工程有限责任公司 | The multiple degrees of freedom formula blowing device and its application method of a kind of sintering |
| CN110118353A (en) * | 2019-06-14 | 2019-08-13 | 郴州华峰能源科技有限公司 | The nozzles of straw burning machine |
-
1991
- 1991-07-22 CN CN 91104867 patent/CN1069324A/en active Pending
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101451714B (en) * | 2007-11-30 | 2012-08-22 | 皮亚尔取暖工业总集团 | Double flow annular pipe and combustor including the double flow annular pipe |
| CN101280917B (en) * | 2008-05-13 | 2010-04-14 | 吕伟鹏 | Coal gas, coal fines and oxygen-enriched mixed combustion device |
| CN103443541A (en) * | 2011-04-05 | 2013-12-11 | 气体产品与化学公司 | Oxy-fuel furnace and method of heating material in an oxy-fuel furnace |
| CN107355783A (en) * | 2016-05-10 | 2017-11-17 | 中冶长天国际工程有限责任公司 | The multiple degrees of freedom formula blowing device and its application method of a kind of sintering |
| CN107355783B (en) * | 2016-05-10 | 2023-09-01 | 中冶长天国际工程有限责任公司 | Multi-degree-of-freedom type injection device for sintering and application method thereof |
| CN110118353A (en) * | 2019-06-14 | 2019-08-13 | 郴州华峰能源科技有限公司 | The nozzles of straw burning machine |
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