CN102951859A - Heat accumulating type lime kiln - Google Patents

Heat accumulating type lime kiln Download PDF

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Publication number
CN102951859A
CN102951859A CN2012104090277A CN201210409027A CN102951859A CN 102951859 A CN102951859 A CN 102951859A CN 2012104090277 A CN2012104090277 A CN 2012104090277A CN 201210409027 A CN201210409027 A CN 201210409027A CN 102951859 A CN102951859 A CN 102951859A
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preheating
preheating chamber
kiln
heat
chamber
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CN2012104090277A
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CN102951859B (en
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贾会平
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Shijiazhuang Xinhua Energy Environmental Protection Technology Co Ltd
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Shijiazhuang Xinhua Energy Environmental Protection Technology Co Ltd
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    • YGENERAL 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
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02PCLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P40/00Technologies relating to the processing of minerals
    • Y02P40/40Production or processing of lime, e.g. limestone regeneration of lime in pulp and sugar mills

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Abstract

The invention relates to a heat accumulating type lime kiln which comprises a kiln body, an air blower, a cooling fan, a charging system, a discharging system and an exhaust emission system, wherein the kiln body is provided with a charging hole and a discharging hole and is internally provided with a calcining belt and a cooling belt; the kiln body is of a sleeve structure, a beam structure and an arch bridge structure; the lime kiln is provided with a first preheating chamber and a second preheating chamber which are arranged on the ground or the upper part of the kiln body; the two preheating chambers are used for alternately accumulating heat and preheating combustion air, and when one preheating chamber is used for exhausting smoke and accumulating heat, and the other preheating chamber is used for preheating air. According to the invention, the kiln body is combined with the two independently installed preheating chambers, calcined materials in the preheating chambers are used as heat accumulating bodies, the two preheating chambers are used for alternately accumulating heat and preheating combustion air, high-temperature smoke generated in a calcining process is used for accumulating heat in the preheating chambers, the materials accumulating the heat discharge heat for preheating the combustion air, wasteheat of the smoke is fully utilized so that waste heat is favorably fully used, and energy consumption and production cost of lime are reduced.

Description

A kind of heat accumulating type limestone kiln
Technical field
The invention belongs to building materials, metallurgy, chemical production equipment technical field, relate to a kind of heat accumulating type limestone kiln.
Background technology
Telescopic shaft furnace has another name called ring kiln, originates from Teller company of the graceful department of German Beckenbach Weir, and existing more than 300 cover for seat cartridge type shaft furnaces come into operation in the world.Practice shows, telescopic shaft furnace equipment is simple, and Operation and maintenance are convenient, and Working environment is better, and calcination product is superior in quality, is a kind of very promising Novel furnace.But telescopic shaft furnace complex structure, build and operation easier large, and exist interchanger easily to stop up, the problem such as UTILIZATION OF VESIDUAL HEAT IN is insufficient restricts sleeve kiln in a large amount of uses of China.Same beam-type limekiln and arch bridge kiln also exist UTILIZATION OF VESIDUAL HEAT IN insufficient, the problem that energy consumption is high.
Granted publication number is that the Chinese patent of CN2937979Y discloses a kind of " annular lime kiln of calcining fuel gas with low heat value ".The fuel that this patent is used is low calorie fuels gas, but the problem of unresolved above-mentioned prior art.
Summary of the invention
The purpose of this invention is to provide a kind of heat accumulating type limestone kiln, utilize by the calcining raw materials accumulation of heat, warm-up combustion-supporting air takes full advantage of the waste heat of flue gas, reduces energy expenditure, cuts down finished cost, and increases economic efficiency.
Heat accumulating type of the present invention limestone kiln comprises kiln body, gas blower, cooling blower, feed system, discharge system and exhaust emission system.The kiln body is provided with opening for feed, discharge port, is provided with calcining zone and cooling zone in the kiln body.Calcining zone is provided with combustion equipment, and combustion equipment is provided with fuel oil atomizer and air nozzle, and fuel oil atomizer is connected with fuel conduit; The top of calcining zone is provided with suction bar or exhanst gas outlet, and suction bar is provided with the cavity of heat-eliminating medium circulation, and cooling blower is connected to cooling zone.The limestone kiln is provided with the first preheating chamber and the second preheating chamber, and the first preheating chamber and the second preheating chamber are installed in the top of ground or kiln body.It is suitable for reading that the first preheating chamber and the second preheating chamber are respectively equipped with preheating chamber opening for feed, preheating chamber discharge port, gas end opening and gas.The preheating chamber discharge port is connected with opening for feed by material transfer equipment.The gas end opening of the first preheating chamber is connected air nozzle with suction bar respectively by No. 4 T-valve and is connected with combustion equipment, the gas end opening of the second preheating chamber passes through No. 3 T-valve is connected air nozzle with suction bar respectively and is connected with combustion equipment.The gas of the first preheating chamber is suitable for reading to be passed through No. 1 T-valve and is connected with blowdown system with gas blower respectively, and the gas of the second preheating chamber is suitable for reading to be passed through No. 2 T-valve and be connected with blowdown system with gas blower respectively.
Selection scheme one is the kiln body of tube-in-tube structure, and combustion equipment is the combustion chamber.The calcining zone of tube-in-tube structure kiln body is provided with inner core, injector, 3~8 upper combustion chamber and 3~8 lower combustion chamber, the same layer combustion chamber is evenly arranged, upper and lower layer combustion chamber staggered arrangement, link to each other by firebridge between each combustion chamber and the inner core, firebridge is the arch form structure that laying fireproof bricks forms.Cooling zone is provided with shunting body, and sleeve is provided with interlayer, and the bottom of interlayer is connected with blower fan, the interlayer injection air port that is connected to injector suitable for reading, the top that is connected to inner core by the injection air port of injector.
Selection scheme two is girder structure kiln body, and combustion equipment is burning beam.The calcining zone of girder structure kiln body is provided with two-layer burning beam, every layer of 2~5 burning beam.Lower suction bar is selected to be provided with in the middle part of cooling zone, and burning beam and lower suction bar are provided with the cavity of heat-eliminating medium circulation.
Selection scheme three is arch bridge structure kiln body, and combustion equipment is the combustion chamber.The calcining zone of arch bridge structure kiln body is provided with two-layer arch bridge, and every layer is provided with 2~5 arch bridges, and the combustion chamber is positioned at the both sides of arch bridge.
Material transfer equipment is pipe chain transfer roller, chapelet or worm conveyor.
The mode of operation in heat accumulating type of the present invention limestone kiln is: two preheating chambers hocket accumulation of heat and warm-up combustion-supporting air, and when a preheating chamber is discharged fume accumulation of heat, another preheating chamber preheated air.Entered the preheating chamber of warm through T-valve by the air of gas blower generation, the material in the preheating chamber is emitted the heat preheated air, and the high temperature air after the preheating is sent into combustion equipment as combustion air.High-temperature flue gas enters heat-accumulating process through T-valve preheating chamber carries out accumulation of heat to limestone material, and exothermic flue gas discharges to blowdown system through T-valve.
The preheating chamber associating that install by kiln body and two platform independent in heat accumulating type of the present invention limestone kiln, utilize the calcined material of preheating chamber to make heat storage, two preheating chambers hocket accumulation of heat and warm-up combustion-supporting air, the high-temperature flue gas that calcination process produces utilizes calcined material to carry out accumulation of heat as heat storage, material after the accumulation of heat is emitted the heat warm-up combustion-supporting air, take full advantage of the waste heat of flue gas, be conducive to taking full advantage of of used heat, reduce energy expenditure and lime production cost.The kiln body in heat accumulating type limestone kiln (comprising calcining zone, cooling zone) and preheating chamber split are conducive to reduce the height of equipment, and handled easily reduces process cost.
Description of drawings
Fig. 1 is the schematic diagram in tube-in-tube structure heat accumulating type limestone kiln;
Fig. 2 is the schematic diagram in girder structure heat accumulating type limestone kiln;
Fig. 3 is the schematic diagram in arch bridge structure heat accumulating type limestone kiln;
Fig. 4 is the schematic diagram of another embodiment of tube-in-tube structure heat accumulating type limestone kiln.
Wherein:
1-gas blower, 2-No. 1 T-valve, 3-preheating chamber opening for feed, 4-gas is suitable for reading, the 5-the first preheating chamber, 6-gas end opening, 7-preheating chamber discharge port, 8-material transfer equipment, 9-No. 2 T-valve, the 10-the second preheating chamber, 11-No. 3 T-valve, 12-No. 4 T-valve, 13-opening for feed, 14-suction bar, 15-firebridge, 16-upper combustion chamber, 17-injection air port, 18-injector, 19-lower combustion chamber, 20-inner core, 21-interlayer, 22-shunting body, 23-discharge port, 24-cooling blower, 25-preheating zone, 26-burning beam, 27-calcining zone, 28-lower suction bar, 29-cooling zone, 30-arch bridge, 31-kiln body, 32-No. 5 T-valve.
Embodiment
Embodiment 1
Heat accumulating type of the present invention limestone kiln is the limestone kiln of tube-in-tube structure as shown in Figure 1, comprises kiln body, gas blower 1, cooling blower 24, feed system, discharge system and exhaust emission system.The kiln body is provided with opening for feed 13, discharge port 23, is provided with calcining zone and cooling zone in the body, and calcining zone is provided with combustion equipment.The kiln body is tube-in-tube structure, and the combustion equipment in tube-in-tube structure heat accumulating type limestone kiln is the combustion chamber.The calcining zone of tube-in-tube structure kiln body is provided with inner core 20, injector 18,6 upper combustion chamber 16 and 6 lower combustion chamber 19, the same layer combustion chamber is evenly arranged, upper and lower layer combustion chamber staggered arrangement, link to each other by firebridge 15 between each combustion chamber and the inner core, firebridge is the arch form structure that laying fireproof bricks forms.Cooling zone is provided with shunting body 22, and sleeve is provided with interlayer 21, and the bottom of interlayer is connected with blower fan, the injection air port 17 that is connected to injector suitable for reading, the top that is connected to inner core 20 by the injection air port of injector.The top of calcining zone is provided with suction bar 14, and suction bar is provided with the cavity of heat-eliminating medium circulation, and cooling blower is connected to cooling zone.The limestone kiln is provided with the first preheating chamber 5 and the second preheating chamber 10, the second preheating chambers are installed in ground.The first preheating chamber and the second preheating chamber are respectively equipped with preheating chamber opening for feed 3, preheating chamber discharge port 7, gas end opening 6 and gas suitable for reading 4.Preheating chamber discharge port 7 is connected with opening for feed 13 by material transfer equipment 8, and material transfer equipment is chapelet.The gas end opening of the first preheating chamber 5 is connected air nozzle with suction bar 14 respectively by No. 4 T-valve 12 and is connected with the combustion chamber, the gas end opening of the second preheating chamber 10 passes through No. 3 T-valve 11 is connected air nozzle with suction bar 14 respectively and is connected with the combustion chamber.The gas of the first preheating chamber suitable for reading 4 is connected with blowdown system with gas blower 1 respectively by No. 1 T-valve 2, and the gas of the second preheating chamber is suitable for reading to be passed through No. 2 T-valve 9 and be connected with blowdown system with gas blower 1 respectively.
The working process in tube-in-tube structure heat accumulating type limestone kiln is, limestone material enters the first preheating chamber 5 and the second preheating chamber 10 through replacing preheating chamber opening for feed 3, operate in the first preheating chamber preheating downwards and enter calcining zone calcining by preheating chamber discharge port 7, chapelet, opening for feed 13, Wingdale is calcined after flue gas that calcining zone is produced by two-layer combustion chambers burn is to preheating.Lime goes out device through the cooling zone cooling by discharge port 23.The mode of operation of upper lower combustion chamber is identical with sleeve kiln, and the combustion chamber, top is little thermal load, and lower combustion chamber is large thermal load, and combustion chamber, top coal gas is excessive, the lower combustion chamber air excess.Roots blower is that the interlayer of inner sleeve blasts cooling air in the working process, warm air behind the cooling sandwith layer passes into injector as the injection source of the gas, the part of smoke that produces after lower floor's combustion chambers burn and the warm air of cool lime are under the effect of injector, sucked by lower inner core bottom, feed lower combustion chamber through behind the injector, as 2 combustion airs.Therefore, at the calcining intersegmental part, form two adverse current calcining zones and one and flow calcining zone.The mode of gas operation is, the air that gas blower 1 bloats enters the first preheating chamber through No. 1 T-valve 2 respectively, air is emitted heat at the first preheating chamber 5 by the material after the accumulation of heat and is preheating to 800 ℃, carries out combustion-supporting burning through gas end opening 6, No. 3 T-valve 11 to upper combustion chamber 16 and lower combustion chamber 19.The flue gas that burning produces is extracted out by suction bar 14, and flue gas is through No. 4 T-valve 12, gas end opening 6 to second preheating chambers, 10 preheating limestone material and carry out accumulation of heat, and flue-gas temperature is lower than 100 ℃ behind the preheating material, discharges to blowdown system through No. 2 T-valve 9.The hocket accumulation of heat and emit the heat preheated air of two preheating chambers, the action by each T-valve realizes blocked operation, whole process automation is carried out.
Embodiment 2
Another embodiment of the present invention as shown in Figure 2, the kiln body is girder structure, combustion equipment is burning beam.The calcining zone 27 of girder structure kiln body is provided with two-layer burning beam 26, and the upper strata is provided with 3 burning beams, and lower floor is provided with 2 burning beams, two-layer burning beam staggered arrangement.Cooling zone 29 selects to be provided with lower suction bar 28.
Embodiment 3
The 3rd kind of embodiment of the present invention as shown in Figure 4, the kiln body is arch bridge structure, combustion equipment is the combustion chamber.The calcining zone of arch bridge structure kiln body is provided with two-layer arch bridge 30, and the upper strata is provided with 3 arch bridges, and lower floor is provided with 2 arch bridges 30, two-layer arch bridge staggered arrangement, and the combustion chamber is positioned at the both sides of arch bridge.The middle part of arch bridge structure kiln body is contraction structure, and the diameter of waist is less than the diameter of upper and lower.The contraction structure at middle arch bridge position is accelerated the calcining zone material flow, reduces material in the residence time of high-temperature zone, is conducive to improve the activity degree of lime product.
Embodiment 4
The 4th kind of embodiment of the present invention as shown in Figure 4, the first preheating chamber 5 and the second preheating chamber 10 are positioned at the top of kiln body.Material alternately directly enters the kiln body through preheating chamber opening for feed 3 by preheating chamber discharge port 7 and opening for feed 13 and calcines.The air of flue gas after opening for feed 13 and preheating chamber discharge port 7 alternately enter the first preheating chamber 5 and the second preheating chamber 10, the first preheating chambers and the second preheating chamber preheating enters respectively the air nozzle of combustion chamber through No. 5 T-valve 32.Mounting structure is conducive to the conveying between the material about preheating chamber and the kiln body, saves material transfer equipment, reduces facility investment, process cost and equipment maintenance cost, is conducive to long-term operation.

Claims (7)

1. heat accumulating type limestone kiln, comprise kiln body (31), gas blower (1), cooling blower (24), feed system, discharge system and exhaust emission system, described kiln body is provided with opening for feed (13) and discharge port (23), is provided with calcining zone and cooling zone in the body; Described calcining zone is provided with combustion equipment, and combustion equipment is provided with fuel oil atomizer and air nozzle, and fuel oil atomizer is connected with fuel conduit; The top of calcining zone is provided with suction bar (14) or exhanst gas outlet, suction bar is provided with the cavity of heat-eliminating medium circulation, described cooling blower is connected to cooling zone, it is characterized in that: described limestone kiln is provided with the first preheating chamber (5) and the second preheating chamber (10), and described the first preheating chamber and the second preheating chamber are installed in the top of ground or kiln body; Described the first preheating chamber and the second preheating chamber are respectively equipped with preheating chamber opening for feed (3), preheating chamber discharge port (7), gas end opening (6) and gas (4) suitable for reading; Described preheating chamber discharge port (7) is connected with opening for feed (13) by material transfer equipment (8); The gas end opening of described the first preheating chamber (5) is connected air nozzle with suction bar (14) respectively by No. 4 T-valve (12) and is connected with combustion equipment, the gas end opening of described the second preheating chamber (10) passes through No. 3 T-valve (11) is connected air nozzle with suction bar (14) respectively and is connected with combustion equipment; The gas of described the first preheating chamber (4) suitable for reading is connected with blowdown system with gas blower (1) respectively by No. 1 T-valve (2), and the gas of described the second preheating chamber No. 2 T-valve (9) that pass through suitable for reading are connected with blowdown system with gas blower (1) respectively.
2. heat accumulating type according to claim 1 limestone kiln, it is characterized in that: described kiln body is tube-in-tube structure, the combustion equipment in tube-in-tube structure limestone kiln is the combustion chamber; The calcining zone of described tube-in-tube structure kiln body is provided with inner core (20), injector (18), 3~8 upper combustion chamber (16) and 3~8 lower combustion chamber (19), the same layer combustion chamber is evenly arranged, link to each other by firebridge (15) between the upper and lower layer combustion chamber staggered arrangement, each combustion chamber and inner core; Described cooling zone is provided with shunting body (22), and described sleeve is provided with interlayer (21), and the bottom of described interlayer is connected with blower fan, the interlayer injection air port (17) that is connected to injector suitable for reading, the top that is connected to inner core (20) by the injection air port of injector.
3. according to heat accumulating type claimed in claim 2 limestone kiln, it is characterized in that: the arch form structure that described firebridge (15) forms for laying fireproof bricks.
4. according to heat accumulating type claimed in claim 1 limestone kiln, it is characterized in that: described kiln body is girder structure, and the combustion equipment in girder structure limestone kiln is burning beam; The calcining zone (27) of described girder structure kiln body is provided with two-layer burning beam (26), every layer of 2~5 burning beam; The burning beam body is provided with the cavity of heat-eliminating medium circulation.
5. according to heat accumulating type claimed in claim 4 limestone kiln, it is characterized in that: the middle part of cooling zone (29) is provided with lower suction bar (28), and lower suction bar is provided with the cavity of heat-eliminating medium circulation.
6. according to heat accumulating type claimed in claim 1 limestone kiln, it is characterized in that: described kiln body is arch bridge structure, and the combustion equipment in arch bridge structure limestone kiln is the combustion chamber; The calcining zone of described arch bridge structure kiln body is provided with two-layer arch bridge (30), and every layer is provided with 2~5 arch bridges, and described combustion chamber is positioned at the both sides of arch bridge.
7. according to heat accumulating type claimed in claim 1 limestone kiln, it is characterized in that: described material transfer equipment is pipe chain transfer roller, chapelet or worm conveyor.
CN201210409027.7A 2012-10-24 2012-10-24 Heat accumulating type lime kiln Active CN102951859B (en)

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CN102951859B CN102951859B (en) 2014-08-06

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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103482889A (en) * 2013-09-16 2014-01-01 石家庄新华能源环保科技股份有限公司 Heat accumulating type material calcinating device
CN104119006A (en) * 2014-07-04 2014-10-29 石家庄新华能源环保科技股份有限公司 Lime shaft kiln with internally-installed combustion chambers
CN111003950A (en) * 2020-01-21 2020-04-14 上海柯来浦能源科技有限公司 Beam kiln for producing lime

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102557492A (en) * 2012-01-06 2012-07-11 石家庄市新华工业炉有限公司 Heat accumulating type double-hearth lime kiln

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102557492A (en) * 2012-01-06 2012-07-11 石家庄市新华工业炉有限公司 Heat accumulating type double-hearth lime kiln

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103482889A (en) * 2013-09-16 2014-01-01 石家庄新华能源环保科技股份有限公司 Heat accumulating type material calcinating device
CN104119006A (en) * 2014-07-04 2014-10-29 石家庄新华能源环保科技股份有限公司 Lime shaft kiln with internally-installed combustion chambers
CN111003950A (en) * 2020-01-21 2020-04-14 上海柯来浦能源科技有限公司 Beam kiln for producing lime

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