CN202024353U - Enriched oxygen or pure oxygen air supply high-temperature oxygen deficient combustion system - Google Patents

Enriched oxygen or pure oxygen air supply high-temperature oxygen deficient combustion system Download PDF

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Publication number
CN202024353U
CN202024353U CN2011200719914U CN201120071991U CN202024353U CN 202024353 U CN202024353 U CN 202024353U CN 2011200719914 U CN2011200719914 U CN 2011200719914U CN 201120071991 U CN201120071991 U CN 201120071991U CN 202024353 U CN202024353 U CN 202024353U
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oxygen
pure
oxygen enrichment
pure oxygen
heating furnace
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CN2011200719914U
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郑克明
冯娜
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Beijing All-Kcal Energy Technology Co Ltd
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Beijing All-Kcal Energy 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
    • Y02EREDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E20/00Combustion technologies with mitigation potential
    • Y02E20/34Indirect CO2mitigation, i.e. by acting on non CO2directly related matters of the process, e.g. pre-heating or heat recovery

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Abstract

The utility model relates to an enriched oxygen or pure oxygen air supply high-temperature oxygen deficient combustion system, which belongs to the technical field of a heating furnace and comprises an enriched oxygen or pure oxygen device, a continuous waste heat recovery device, a heating furnace and a high-temperature oxygen deficient combustor, wherein the enriched oxygen or pure oxygen device is connected with the continuous waste heat recovery device through a pipeline, the continuous waste heat recovery device is positioned in a heating furnace flue, an outlet of the continuous waste heat recovery device is connected with an enriched oxygen or pure oxygen inlet of the high-temperature oxygen deficient combustor, and the high-temperature oxygen deficient combustor is arranged on a heating furnace wall. The enriched oxygen or pure oxygen air supply high-temperature oxygen deficient combustion system provided by the utility model has the advantages that enriched oxygen or pure oxygen air supply under different heating capacities is realized, the content of nitrogen in flue gas is reduced, and simultaneously the content of triatomic molecules in the furnace gas is increased, so waste heat taken away by the flue gas is reduced and the heat transfer efficiency in the furnace is improved.

Description

The High Temperature Air Combustion system of oxygen enrichment or pure oxygen air feed
Technical field
The utility model belongs to the heating furnace technical field, the High Temperature Air Combustion system of a kind of oxygen enrichment or pure oxygen air feed is provided, can realize the High Temperature Air Combustion of oxygen enrichment or pure oxygen air feed, be applied to using gases fuel heating furnace, make the reheating furnace energy-saving consumption reduction time reduce the discharging of oxynitrides again.
Background technology
Heating furnace production all has high energy consumption, oxidization burning loss height, produces the drawback of large quantity of exhaust gas.High energy consumption makes the fuel that heating furnace consumption is a large amount of, has wasted the energy; Higher oxidization burning loss causes the waste that is heated material; Oxynitrides in the large quantity of exhaust gas that produces forms acid rain, and environment is made a very bad impression, and has aggravated Global Greenhouse Effect simultaneously.And along with the raising of various resource prices, the strict more conservation measures and the environmental protection policy of increasingly serious and government of environmental problem, heating furnace production urgent need one cover can be saved energy and reduce the cost and be reduced the combustion system of oxynitrides simultaneously again.
Utilize air-breathing in the traditional combustion, about 79% nitrogen does not participate in burning in the combustion air, forms flue gas on the contrary and takes away a part of heat that burning produces, and wastes energy.And oxygen enrichment and pure oxygen burning technology use oxygen-enriched air or pure oxygen are combustion-supporting, have reduced the nitrogen in the flue gas, have fundamentally reduced the waste heat that flue gas is taken away; Improved triatomic molecule (CO in the furnace gas simultaneously 2, H 2O) ratio, because nitrogen is transparent for heat radiation, and triatomic molecule has blackness, the increase of triatomic molecule ratio makes the furnace gas blackness improve, thereby make radiation heat transfer reinforcement in the stove, improved furnace heat transfer efficient, reduced fuel consumption, but simultaneously because the flame temperature height makes oxidization burning loss increase.During general gas fuel combustion, the oxynitrides of generation is mainly heating power type oxynitrides, because the flame temperature height of oxygen enrichment or pure oxygen burning, causes that heating power type oxynitrides growing amount rolls up in the burning.It is introduced, for methane fuel, the oxynitride concentration that burning produces during oxygen concentration 30% is 3 times of ordinary air combustion, the oxynitride concentration that produces during oxygen concentration 80% then is 100 times of ordinary air combustion, because the nitrogen amount that infeeds reduces, the oxynitride concentration that burning produces is 8 times of ordinary air combustion when adopting pure oxygen.But as a whole, on heating furnace, adopt traditional oxygen enrichment or pure oxygen burning technology, flame combustion temperature height, the oxynitrides total amount of discharging is multiplied, and also is the main cause that causes oxidization burning loss high simultaneously.
Flame combustion temperature height, furnace gas oxygen concentration height and furnace gas nitrogen content height are to cause oxidization burning loss seriously to reach the main cause that high oxynitrides generates.Participate in obtaining high temperature after the gas preheating of burning, can realize smooth combustion under the oxygen deprivation concentration conditions, the oxysome volume concentrations that contains of combustion zone is reduced to 4% and still can keeps smooth combustion.Adopt the High Temperature Air Combustion mode, oxygen concentration is low in the stove, and the flame volume also so at double enlarges, and has reduced the flame peak temperature significantly, furnace temperature evenly and be lower than the generation temperature of heating power type oxynitrides has reached the effect that oxidization burning loss is low, oxynitrides is low.But traditional combustion with meagre oxygen uses air-breathing, and about 79% nitrogen increases exhaust gas volumn in the air, takes away a large amount of waste heats, reduces the thermal efficiency, and causes the burden of follow-up heat transmission equipment and environmental protection equipment.
Therefore; provide a kind of oxygen-enriched air or pure oxygen air feed are carried out high temperature preheating after, in burner hearth, form the burning of oxygen deprivation concentration, reduce the discharging of oxidization burning loss and oxynitrides; improve simultaneously thermal efficiency of heating furnace combustion system, energy-saving and cost-reducing and environmental protection is significant to the heating furnace field.
Summary of the invention
The purpose of this utility model is to provide the High Temperature Air Combustion system of a kind of oxygen enrichment or pure oxygen air feed, utilize oxygen-enriched air or pure oxygen air feed, reduce flue gas and take away waste heat, strengthening furnace heat transfer utilizes the high-temperature flue gas waste heat that pre-thermal medium (oxygen-enriched air or pure oxygen) is carried out the preheating of continuous high-efficient simultaneously, associated working by each part of system makes fuel be issued to the High Temperature Air Combustion condition in the condition of different oxygen content air feeds, the oxidizing atmosphere of reduction in the heating furnace to be reducing the material oxidization burning loss rate that is heated significantly, thereby solve the heating furnace high energy consumption, the problem of low lumber recovery and oxynitrides discharging.
The utility model comprises oxygen enrichment or pure oxygen device 1, waste-heat recovery device 2, heating furnace 3, High Temperature Air Combustion device 4 continuously, oxygen enrichment or pure oxygen device 1 are connected with continuous waste-heat recovery device 2 by pipeline, waste-heat recovery device 2 is arranged in the heating furnace flue continuously, the outlet of waste-heat recovery device 2 is connected with the oxygen enrichment or the pure oxygen inlet of High Temperature Air Combustion device 4 continuously, and High Temperature Air Combustion device 4 is installed on heating furnace 3 furnace walls.Waste-heat recovery device 2 places the flue of heating furnace 3 continuously, pressure 6000Pa~the 7000Pa that obtains by oxygen enrichment or pure oxygen device 1, oxygen content is greater than 21% oxygen-enriched air or pure oxygen, enter the continuous waste-heat recovery device 2 that places flue, high-temperature flue gas heat exchange in continuous waste-heat recovery device 2 with heating furnace 3 generations, make the exhaust gas temperature of flue gas reduce to 250~300 ℃, simultaneously oxygen-enriched air or pure oxygen are preheating to 500~550 ℃.High-temperature oxygen-enriched air or pure oxygen, combustion gas and partial fume are mixed by High Temperature Air Combustion device 4, realize smooth combustion in stove in the oxygen-lean atmosphere, have reduced the oxidization burning loss and the oxynitrides that are heated material when improving the thermal efficiency and have generated.
The utility model is used for High Temperature Air Combustion device air feed with oxygen-enriched air or pure oxygen, thereby the content of nitrogen in the minimizing flue gas, fundamentally reduce the waste heat that flue gas is taken away, reduce the burden of follow-up heat transmission equipment and environmental protection equipment, improve triatomic molecule (CO in the furnace gas simultaneously 2, H 2O) content, 0.795 when making the furnace gas blackness by air-breathing brought up to 0.819 of pure oxygen burning, strengthens radiation heat transfer, improves the efficiency of heating surface.By oxygen enrichment or pure oxygen device 1, the whole combustion system Collaborative Control formed of waste-heat recovery device 2, heating furnace 3, High Temperature Air Combustion device 4 continuously: oxygen enrichment or pure oxygen device are controlled oxygen content, pressure, the flow of oxygen enrichment or pure oxygen; Waste-heat recovery device is controlled oxygen enrichment or pure oxygen preheat temperature continuously; The High Temperature Air Combustion device is realized High Temperature Air Combustion; Parameters such as heating furnace feedback furnace gas temperature, furnace gas oxygen content make combustion system can realize combustion with meagre oxygen and technology heating-up temperature.
The utility model has designed a kind of High Temperature Air Combustion device, this High Temperature Air Combustion device utilizes inner flue gas of the stove to reflux, reduce the oxygen concentration of oxygen-enriched air or pure oxygen, realize the furnace high-temperature combustion with meagre oxygen, ignition temperature is lower than the generation temperature of heating power type oxynitrides, and special structural design makes burner still can realize stable combustion with meagre oxygen under the condition of different oxygen content air feeds simultaneously.
Each functional structure of High Temperature Air Combustion device comprises fuel gas inlet 5, epoxy import 6, oxygen enrichment nozzle inlet 7, oxygen enrichment nozzle necking down 8, flue gas recirculation passage 9, oxygen enrichment nozzle 10, middle part epoxy passage 11, blast tube 12.Fuel gas inlet 5 is connected with fuel gas pipeline, epoxy import 6 is connected with high-temperature oxygen-enriched or pure oxygen pipeline with oxygen enrichment nozzle inlet 7, oxygen enrichment nozzle necking down 8 is positioned at oxygen enrichment nozzle inlet rear portion, and be connected with flue gas recirculation passage 9 and oxygen enrichment nozzle 10, middle part epoxy passage 11 is positioned at blast tube 12 peripheries, and flue gas recirculation passage 9, oxygen enrichment nozzle 10, middle part epoxy passage 11, blast tube 12 are all linked in the heating furnace burner hearth.Combustion gas enters burner by fuel gas inlet 5, oxygen-enriched air or pure oxygen enter burner by epoxy import 6 and oxygen enrichment nozzle inlet 7, oxygen-enriched air or pure oxygen at the oxygen enrichment nozzle passage after undergauge 8 quickens, entrainment the flue gas in the flue gas recirculation passage 9, by reducing nozzle diameter, regulate oxygen enrichment or pure oxygen pressure in 6000~7000Pa scope, make the gaseous mixture oxygen content of entrainmenting behind the flue gas reach 4~15%.Oxygen enrichment in the middle part epoxy passage 11 or pure oxygen mix smooth combustion with combustion gas in the blast tube 12 in the exit.Combustion gas continues the oxygen deprivation concentration gaseous mixture mixed combustion of diffusion and 10 ejections of oxygen enrichment nozzle.
Advantage of the present utility model and good effect:
Special feature of the present utility model is to form the various piece associated working of combustion system, oxygen enrichment or pure oxygen air feed under the different heating ability have been realized, reduced the nitrogen content in the flue gas, improved the content of triatomic molecule in the furnace gas simultaneously, thereby reduced the waste heat that flue gas takes away and improved heat exchange efficiency in the stove.Another feature of the present invention is that combustion system has adopted a kind of combustion with meagre oxygen device that can efficient burning can reduce the oxynitrides discharging again, and still can realize stable combustion with meagre oxygen under different oxygen content air feed conditions.Burner by directly taking from burner hearth the backflow flue gas but not the emptying flue gas waters down air oxygen concentration, by the optimization on structural improvement and the parameter, improved the flow velocity of oxygen-enriched air or pure oxygen, the oxygen enrichment passage has formed bigger negative pressuren zone, the backflow flue gas can need not any power set and enter the oxygen enrichment passage under suction function, high-temperature flue gas enter the oxygen concentration that has greatly watered down on the one hand oxygen-enriched air or pure oxygen, on the other hand to high-temperature oxygen-enriched air or pure oxygen preheating once more, burning is carried out under the oxygen deprivation state, the oxidization burning loss rate and the oxynitrides growing amount that are heated material significantly reduce, combustion position is better, and pressure and change nozzle diameter by control oxygen-enriched air or pure oxygen, under the condition of different oxygen content air feeds, still can regulate the mixed proportion of oxygen-enriched air or pure oxygen and flue gas, thereby make gaseous mixture reach required oxygen concentration.Fuel savings of the present invention, reduce oxidization burning loss, the discharging of reduction oxynitrides, economic benefit and obvious environment benefit.
Description of drawings
Fig. 1 is a total system schematic diagram of the present utility model.Wherein, oxygen enrichment or pure oxygen device 1, continuous waste-heat recovery device 2, heating furnace 3, High Temperature Air Combustion device 4.
Fig. 2 is the structural representation of High Temperature Air Combustion device.Wherein, fuel gas inlet 5, epoxy import 6, oxygen enrichment nozzle inlet 7, oxygen enrichment nozzle necking down 8, flue gas recirculation passage 9, oxygen enrichment nozzle 10, middle part epoxy passage 11, blast tube 12.
The specific embodiment
The utility model comprises oxygen enrichment or pure oxygen device 1, waste-heat recovery device 2, heating furnace 3, High Temperature Air Combustion device 4 continuously, oxygen enrichment or pure oxygen device 1 are connected with continuous waste-heat recovery device 2 by pipeline, waste-heat recovery device 2 is arranged in the heating furnace flue continuously, the outlet of waste-heat recovery device 2 is connected with the oxygen enrichment or the pure oxygen inlet of High Temperature Air Combustion device 4 continuously, and High Temperature Air Combustion device 4 is installed on heating furnace 3 furnace walls.Waste-heat recovery device 2 places the flue of heating furnace 3 continuously, pressure 6000Pa~the 7000Pa that obtains by oxygen enrichment or pure oxygen device 1, oxygen content is greater than 21% oxygen-enriched air or pure oxygen, enter the continuous waste-heat recovery device 2 that places flue, high-temperature flue gas heat exchange in continuous waste-heat recovery device 2 with heating furnace 3 generations, make the exhaust gas temperature of flue gas reduce to 250~300 ℃, simultaneously oxygen-enriched air or pure oxygen are preheating to 500~550 ℃.High-temperature oxygen-enriched air or pure oxygen, combustion gas and partial fume are mixed by High Temperature Air Combustion device 4, realize smooth combustion in stove in the oxygen-lean atmosphere, have reduced the oxidization burning loss and the oxynitrides that are heated material when improving the thermal efficiency and have generated.
Oxygen enrichment or pure oxygen device 1 are according to the parameters such as preheat temperature of furnace temperature, furnace gas oxygen concentration, oxygen enrichment or pure oxygen, provide specified pressure (6000~7000Pa), the oxygen-enriched air or the pure oxygen of oxygen content (>21%), be sent to continuous waste-heat recovery device 2, low temperature oxygen-enriched air or pure oxygen absorb flue gas physics heat by heat exchange element continuously, with preheating temperature to 500~550 ℃, deliver to High Temperature Air Combustion device 4 then.The high-temperature flue gas that heating furnace 3 produces is introduced into continuous waste-heat recovery device 2, and the physics heat of flue gas is passed to heat exchange element, enters atmosphere through chimney.The temperature of efficient waste-heat recovery device 2 monitoring flue gas, oxygen-enriched air or pure oxygens is regulated and is imported and exported two heat transferring mediums (flue gas, oxygen-enriched air or pure oxygen) flow velocity.Oxygen-enriched air or pure oxygen enter burner by burner epoxy import 6 and oxygen enrichment nozzle inlet 7, oxygen-enriched air or pure oxygen at the oxygen enrichment nozzle passage after undergauge 8 quickens, entrainment the flue gas in the flue gas recirculation passage 9, by reduce nozzle diameter and regulate oxygen-enriched air or the pressure of pure oxygen (6000~7000P), reach requisite oxygen content (4~15%).Oxygen-enriched air in the middle part epoxy passage 11 or pure oxygen mix in the exit with combustion gas in the blast tube 12, play the effect of raising flame holding.Combustion gas continues the gaseous mixture mixed combustion of the oxygen deprivation concentration of diffusion and 10 ejections of oxygen enrichment nozzle.Because the gaseous mixture oxygen concentration reduces, the flame volume obviously increases, and temperature field in furnace is even, and temperature range reduces.The associated working of whole combustion system, make heating furnace can realize combustion with meagre oxygen under the different heating ability, ignition temperature is lower than the generation temperature of heating power type oxynitrides, and because oxygen-enriched air or pure oxygen air feed, the minimizing of nitrogen in the flue gas has reduced the heat that flue gas is taken away.Triatomic molecule content increases, and radiation heat transfer is strengthened greatly, has improved whole heat exchange efficiency.
Facts have proved that system compares with traditional combustion, native system is energy-conservation 35~50%, and oxidization burning loss reduces about 30%, and the oxynitrides discharging reduces by 50~80%.

Claims (2)

1. the High Temperature Air Combustion system of oxygen enrichment or pure oxygen air feed, comprise oxygen enrichment or pure oxygen device, continuous waste-heat recovery device, heating furnace, High Temperature Air Combustion device, it is characterized in that, oxygen enrichment or pure oxygen device (1) are connected with continuous waste-heat recovery device (2) by pipeline, waste-heat recovery device (2) is arranged in the heating furnace flue continuously, the outlet of waste-heat recovery device (2) is connected with the oxygen enrichment or the pure oxygen inlet of High Temperature Air Combustion device (4) continuously, and High Temperature Air Combustion device (4) is installed on heating furnace (3) furnace wall; Waste-heat recovery device (2) places the flue of heating furnace (3) continuously.
2. the High Temperature Air Combustion system of oxygen enrichment according to claim 1 or pure oxygen air feed, it is characterized in that described High Temperature Air Combustion device (4) comprises fuel gas inlet (5), epoxy import (6), oxygen enrichment nozzle inlet (7), oxygen enrichment nozzle necking down (8), flue gas recirculation passage (9), oxygen enrichment nozzle (10), middle part epoxy passage (11), blast tube (12); Fuel gas inlet (5) is connected with fuel gas pipeline, epoxy import (6) is connected with high-temperature oxygen-enriched or pure oxygen pipeline with oxygen enrichment nozzle inlet (7), oxygen enrichment nozzle necking down (8) is positioned at oxygen enrichment nozzle inlet rear portion, and be connected with flue gas recirculation passage (9) and oxygen enrichment nozzle (10), middle part epoxy passage (11) is positioned at blast tube (12) periphery, and flue gas recirculation passage (9), oxygen enrichment nozzle (10), middle part epoxy passage (11), blast tube (12) are all linked in the heating furnace burner hearth.
CN2011200719914U 2011-03-17 2011-03-17 Enriched oxygen or pure oxygen air supply high-temperature oxygen deficient combustion system Expired - Fee Related CN202024353U (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN106402860A (en) * 2016-11-07 2017-02-15 上海铁戈炉业有限公司 Pure oxygen combustion technology

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN106402860A (en) * 2016-11-07 2017-02-15 上海铁戈炉业有限公司 Pure oxygen combustion technology

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Granted publication date: 20111102

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