CN110822417A - Full-premixing denitration system of gas industrial boiler and control method - Google Patents
Full-premixing denitration system of gas industrial boiler and control method Download PDFInfo
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
- F23C—METHODS OR APPARATUS FOR COMBUSTION USING FLUID FUEL OR SOLID FUEL SUSPENDED IN A CARRIER GAS OR AIR
- F23C6/00—Combustion apparatus characterised by the combination of two or more combustion chambers or combustion zones, e.g. for staged combustion
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
- F23C—METHODS OR APPARATUS FOR COMBUSTION USING FLUID FUEL OR SOLID FUEL SUSPENDED IN A CARRIER GAS OR AIR
- F23C5/00—Disposition of burners with respect to the combustion chamber or to one another; Mounting of burners in combustion apparatus
- F23C5/02—Structural details of mounting
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
- F23D—BURNERS
- F23D14/00—Burners for combustion of a gas, e.g. of a gas stored under pressure as a liquid
- F23D14/02—Premix gas burners, i.e. in which gaseous fuel is mixed with combustion air upstream of the combustion zone
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
- F23D—BURNERS
- F23D14/00—Burners for combustion of a gas, e.g. of a gas stored under pressure as a liquid
- F23D14/46—Details, e.g. noise reduction means
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
- F23D—BURNERS
- F23D14/00—Burners for combustion of a gas, e.g. of a gas stored under pressure as a liquid
- F23D14/46—Details, e.g. noise reduction means
- F23D14/62—Mixing devices; Mixing tubes
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
- F23D—BURNERS
- F23D14/00—Burners for combustion of a gas, e.g. of a gas stored under pressure as a liquid
- F23D14/46—Details, e.g. noise reduction means
- F23D14/70—Baffles or like flow-disturbing devices
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
- F23N—REGULATING OR CONTROLLING COMBUSTION
- F23N1/00—Regulating fuel supply
- F23N1/02—Regulating fuel supply conjointly with air supply
- F23N1/027—Regulating fuel supply conjointly with air supply using mechanical means
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
- F23C—METHODS OR APPARATUS FOR COMBUSTION USING FLUID FUEL OR SOLID FUEL SUSPENDED IN A CARRIER GAS OR AIR
- F23C2201/00—Staged combustion
- F23C2201/30—Staged fuel supply
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
- F23C—METHODS OR APPARATUS FOR COMBUSTION USING FLUID FUEL OR SOLID FUEL SUSPENDED IN A CARRIER GAS OR AIR
- F23C2700/00—Special arrangements for combustion apparatus using fluent fuel
- F23C2700/04—Combustion apparatus using gaseous fuel
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
- F23D—BURNERS
- F23D2203/00—Gaseous fuel burners
- F23D2203/007—Mixing tubes, air supply regulation
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- 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
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E20/00—Combustion technologies with mitigation potential
- Y02E20/34—Indirect 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 invention discloses a full-premixing denitration system of a gas industrial boiler, which comprises a gas pressure regulating valve, an air pressure regulating valve, a premixing system and a combustion system. The premixing system comprises a fuel gas flow divider, an air flow divider, a premixer and a mixing chamber. The gas and the combustion air are respectively subjected to three-stage flow distribution and primary mixing, so that the aim of denitration by using a premixing system and a combustion system is fulfilled, and the emission standard of NOx is achieved. The invention also provides a control method based on the full-premixing denitration system of the gas industrial boiler, which utilizes the gas pressure regulating valve and the air pressure regulating valve to realize the automatic control of the whole system and improves the running stability and the working efficiency of the system.
Description
[ technical field ] A method for producing a semiconductor device
The invention relates to an environment-friendly technology of a gas industrial boiler, in particular to a full-premixing denitration system of the gas industrial boiler and a control method.
[ background of the invention ]
In recent years, the strength of eliminating coal-fired boilers is continuously increased, and the strength of changing coal into gas or changing oil into gas is continuously enhanced, although the 'emission standard of atmospheric pollutants for boilers GB 13271-2014' is issued in 2014, wherein the emission of NOx (namely nitrogen oxides, hereinafter referred to as NOx) is limited below 200 mg.Nm < -3 >, which is only one most basic guiding opinion in the national range; thereafter, local standards are continuously provided in various places, for example, Beijing promulgates a 'Beijing City local standard DB 11/139-2015', the emission limit of NOx is strict, and the emission value is regulated to be below 30mg Nm < -3 >. The emission of the existing small industrial boiler, especially the coal-fired boiler, is only barely in line with the requirements of national standard GB13271-2014 after being modified, obviously, the environmental protection requirements of the boiler and Beijing are far away, so that the Beijing area firstly puts forward the requirement of 'changing coal into gas', even if the boiler is 'changing coal into gas', the NOx emission amount still can not reach the environmental protection requirements of the Beijing jin Ji area if special measures are not taken.
Generally, nitrogen oxide treatment technology starts from two aspects, namely NOx generation inhibition and flue gas aftertreatment technology in the combustion process. In the combustion process, the generation of NOx is generally directly inhibited by using a special combustion mode (through special combustion equipment or a special air distribution mode and the like), the investment cost is generally low, the denitration purpose can be achieved without special equipment or a special system, but the denitration efficiency is generally not more than 50%; the flue gas post-treatment purification technology generally comprises an SCR (flue gas denitration technology, hereinafter referred to as SCR) technology and an SNCR (flue gas desulfurization denitration, hereinafter referred to as SNCR) technology, and generally the SCR denitration efficiency is high and can reach more than 90% at most, but the investment cost is also the highest in the existing denitration technology, and the management and maintenance cost is also high; compared with the SCR technology, the SNCR technology has lower investment, but has stricter requirements on combustion environment, has higher denitration efficiency within a certain temperature range, and obviously reduces the denitration efficiency beyond the temperature window.
The flue gas external recycling technology used by the power station boiler is generally classified into a range for inhibiting the generation of NOx by combustion, the flue gas recycling denitration can generally meet the environmental protection requirement, and the NOx emission is below 30 mg.m < -3 >. This kind of denitration technique also has the application on small-size industrial boiler, but the extrinsic cycle equipment is independent outside the boiler body, and its structure is relatively complicated to small-size gas boiler, and the accessory structure includes: the recirculation duct, the flue gas return damper and the corresponding return flow control system, if these devices leave the factory together with the boiler to affect the aesthetic appearance of the boiler, require additional costs for the user due to the additional part of the auxiliary equipment, thus limiting the use of the devices in small gas boilers.
The method for inhibiting the generation of NOx by using the low-nitrogen combustor is more superior to a small gas boiler by comprehensively considering the investment of various denitration methods and the difference between denitration effects; firstly, the cost for inhibiting the generation of NOx in the combustion process is low; and the second mode has no additional accessory equipment, so that the boiler leaves the factory more beautiful. Traditional combustion methods can be divided into two main categories: premixed combustion and non-premixed combustion. Premixed combustion means that fuel and oxidant are premixed before combustion and then enter a combustor for combustion; the non-premixing means that the fuel and the oxidant independently enter a hearth and are contacted in the hearth to generate a combustion reaction. For large boilers, because of the very large fuel consumption, mixing of the fuel with the oxidant is very difficult or impossible to achieve at all, so that premixed combustion can only be carried out on small boilers or internal combustion engines. The invention relates to a premixing denitration technology used on a small gas boiler.
The early mixing of fuel and combustion air is particularly important for the premixed combustion technology, the previous method only simply mixes the fuel after the fuel enters an air blower and then enters a boiler combustor for combustion, the fuel and the air have independent loops respectively in front of the air blower, the mixing effect is poor, and the combustion effect is inevitably influenced.
Compared with the traditional combustion technology, the premixed combustion technology has the advantages of good combustion stability, wide load regulation range, low NOx emission and the like. However, in the prior premixed combustion technology, high-temperature resistant ceramic is used as a nozzle material of a combustor, and some of the high-temperature resistant ceramic is combusted on the surface of a metal mesh. The porous ceramic plate combustion technology is a research hotspot in the prior premixing technology, is still in the laboratory research stage, has less practical application, and is mainly numerical simulation research abroad; the method is just started in China and has insufficient theoretical support. Some students in China divide the premixed combustion technology into two main categories: lean premixed combustion and water-cooled premixed combustion; for the premixed combustion of lean fuel, if the excess air coefficient is too large, the ignition is easy to be generated on the combustion surface, if the excess air coefficient is too small, the temperature of the metal surface is easy to be too high, and the NOx emission amount is increased under both working conditions, so that the control of the excess air coefficient is critical for the combustion mode; the water-cooled premixing system has a complicated structure, and the number of boiler parts needing to be changed is too many, so that the two premixing methods are inconvenient to use, and therefore, the problems for reducing NOx are as follows: 1. the uneven mixing of the premixed combustion early-stage fuel and the combustion air increases the NOx discharge amount, which does not accord with the regulation; 2. the burner is too complex in structure and inconvenient to use.
[ summary of the invention ]
In order to solve the technical problems, the invention provides a full-premixing denitration system of a gas industrial boiler, which respectively carries out three-stage separation and primary mixing on gas and combustion air, achieves the purpose of premixed combustion by using a premixing system and a combustion system, and controls the final discharge amount of NOx to meet the specified requirements.
The technical scheme adopted by the invention is as follows: the utility model provides a full denitration system that mixes of gas industrial boiler, includes gas pressure regulating valve, air pressure regulating valve, mixes system and combustion system in advance, and gas pressure regulating valve is connected with an import of mixing the system in advance, and air pressure regulating valve is connected with another import of mixing the system in advance, mixes the system in advance and is connected with combustion system. The premixing system comprises a fuel gas flow divider, an air flow divider, a premixer and a mixing chamber. The gas flow divider and the air flow divider are respectively connected with the input end of the premixer, and the output end of the premixer is fixedly connected with the input end of the mixing chamber. The combustion system includes a combustion cylinder and a fire retardant coating, and the cladding of fire retardant coating is on the outer wall top layer of combustion cylinder, has evenly seted up a plurality of burner ports on the section of thick bamboo wall circumference on fire retardant coating.
Compared with the prior art, the invention has the beneficial effects that: simple structure easily operates, carry out the one-level reposition of redundant personnel with gas and combustion-supporting air respectively in gas shunt and air shunt, then carry out the second grade reposition of redundant personnel respectively in the premixer, mix in the mixing chamber, carry out tertiary reposition of redundant personnel at last in the combustion tube, the abundant homogeneous mixing of gas and combustion-supporting air before the burning has been guaranteed to the at utmost, it makes fuel and combustion-supporting air intensive mixing to have realized utilizing the premixing system, abundant assurance combustor surface each position excess air coefficient is even, avoid leading to the purpose that NOx discharges and risees because excess air coefficient is too big or the undersize, it is mesh to utilize special surface combustion tube to carry out the denitration, cover the back-fire relief layer at the combustion tube surface and make denitration efficiency obtain further improvement, make NOx's emission reach the environmental protection requirement.
Preferably, the gas flow divider is composed of a columnar hollow pipe and a circular hollow cavity, and the upper end of the columnar hollow pipe is fixedly connected with the outer wall of the circular hollow cavity.
By adopting the technical scheme, the upper end of the columnar hollow pipe is completely sealed with the outer wall of the circular hollow cavity, and gas is prevented from leaking from the inside so as to avoid unsafe accidents.
Preferably, the air splitter comprises a columnar hollow pipe and a circular hollow cavity, and the upper end of the columnar hollow pipe is fixedly connected with the outer wall of the circular hollow cavity.
Adopt above-mentioned technical scheme, ensure that the upper end of column hollow tube and the outer wall in circular hollow chamber are sealed completely, avoid the air to spill from inside and lead to the tolerance not enough, make the burning insufficient.
Preferably, the premixer is internally provided with a gas chamber and a combustion-supporting air chamber, and the gas chamber and the combustion-supporting air chamber are concentric closed isolation cavities.
By adopting the technical scheme, the gas and the combustion air are prevented from being mixed before entering the mixing chamber, and uneven mixing is avoided.
Preferably, the gas chamber is provided with a plurality of inlets, and the plurality of inlets are respectively connected with the lower end of the columnar hollow pipe of the gas splitter.
By adopting the technical scheme, the purpose of uniformly distributing the fuel gas is realized.
More preferably, the inlets of the combustion air chambers are connected to the lower ends of the columnar hollow pipes of the air diverters, respectively.
By adopting the technical scheme, the purpose of uniformly distributing combustion-supporting is realized.
More preferably, the gas chamber and the combustion air chamber do not communicate with each other.
Adopt above-mentioned technical scheme to realize that gas and combustion-supporting air carry out the purpose of reposition of redundant personnel respectively, prevent that gas and combustion-supporting air from mixing before getting into the mixing chamber, avoid appearing mixing inhomogeneous.
Further preferably, the interior of the combustion can is divided into a plurality of identical combustion chambers.
By adopting the technical scheme, the excess air coefficients of all parts on the surface of the combustor are ensured to be the same, and the mixed gas of the fuel gas and the combustion-supporting air is fully combusted.
It is further preferred that the surface of the combustion cylinder is covered with a fire barrier layer of uniform thickness.
By adopting the technical scheme, the NOx generation amount can be further reduced by selecting the proper thickness of the fire retardant layer.
The invention also provides a control method based on the full-premixing denitration system of the gas industrial boiler, which comprises the following steps of:
step 1, confirming the opening of a gas pressure regulating valve and an air pressure regulating valve when a boiler is in a normal running state;
step 3, opening a gas pressure regulating valve and an air pressure regulating valve according to the load of the boiler;
and 4, if an abnormal combustion signal of the combustion cylinder is received, closing the gas pressure regulating valve in an interlocking manner, closing the air pressure regulating valve in a delayed manner, and performing purging in the boiler and troubleshooting on the combustion cylinder.
The method has the beneficial effects that: by the control method, the automatic control of the whole system is realized by utilizing the gas pressure regulating valve and the air pressure regulating valve, and the stability and the working efficiency of the system operation are improved.
[ description of the drawings ]
FIG. 1 is a schematic diagram of the overall connection of a fully premixed denitrification system;
FIG. 2 is a schematic diagram of a premix system configuration;
FIG. 3 is a cross-sectional view of the premix system configuration;
FIG. 4 is a schematic view of a premixer configuration;
FIG. 5 is a schematic view of a combustion system configuration;
FIG. 6 is a schematic view of a combustion can configuration;
FIG. 7 is a cross-sectional view of a combustion can;
in the figure, 1-air filter; 2-a gas pipe; 3-gas pressure regulating valve; 4-air pressure regulating valve; 40-air tube; 5-a gas splitter; 6-an air splitter; 7-a premix system; 70-a premixer; 71-a mixing chamber; 701-a gas chamber; 702-a combustion air assist chamber; 8-mixed gas conveying pipe; 9-a blower; 10-furnace front connecting pipe; 11-a combustion system; 110-a combustion can; 111-combustion holes; 12-fire barrier layer.
[ detailed description ] embodiments
In the present embodiment, the terms "up", "down", "left" and "right" used to indicate directions correspond to the directions of "up", "down", "left" and "right" in the drawings.
A full-premixing denitration system of a gas industrial boiler is shown in figure 1 and comprises an air filter 1, a gas pipe 2, a gas pressure regulating valve 3, an air pressure regulating valve 4, a premixing system 7, a mixed gas conveying pipe 8, a blower 9, a stokehole connecting pipe 10 and a combustion system 11.
As shown in fig. 1, an air pipe 40 is detachably connected to the outlet of the air filter 1, two middle sections of the air pipe 40 are respectively detachably connected to two ends of the air pressure adjusting valve 4, the air pressure adjusting valve 4 is located at the middle section of the air pipe 40, and the end of the air pipe 40 is connected to one inlet of the premixing system 7. The two ends of the middle of the gas pipe 2 are respectively connected with the two ends of the gas pressure regulating valve 3, and the tail end of the gas pipe 2 is connected with the other inlet of the premixing system 7. The outlet of the premixing system 7 is connected with one end of a mixing gas pipe 8, the other end of the mixing gas pipe 8 is detachably connected with the inlet of a blower 9, the outlet of the blower 9 is detachably connected with one end of a stokehole connecting pipe 10, and the other end of the stokehole connecting pipe 10 is detachably connected with a combustion system 11.
It should be noted that the air filter 1, the gas pipe 2, the gas pressure regulating valve 3, the air pressure regulating valve 4, the mixture gas pipe 8, the blower 9, and the stokehole adapter 10 are all disclosed in the prior art and obtained by purchase or actual processing. The gas pressure regulating valve 3 and the air pressure regulating valve 4 are electric interlocking valves selected for receiving and feeding back signals of the load of the boiler, and the feedback signals are generated and received by regulating the gas quantity and the air quantity through the opening degree of the valves, so that the load of the boiler and the coefficient of excess air in the boiler are regulated, and the complete low-N combustion in the combustible gas boiler is realized.
As shown in fig. 2, the premixing system 7 includes a gas splitter 5, an air splitter 6, a premixer 70 and a mixing chamber 71. The gas flow divider 5 and the air flow divider 6 are coaxially distributed above and below the premixer 70, so that the occupied space of the equipment is saved, the premixing system 7 is compact and simple in structure, and the production cost is saved. The gas splitter 5 and the air splitter 6 are respectively connected with the input end of the premixer 70, and the output end of the premixer 70 is fixedly connected with the input end of the mixing chamber 71, so that gas leakage can be effectively prevented, potential safety hazards are avoided, and safety accidents are reduced. The output end of the mixing chamber 71 is detachably connected with the input end of the mixing gas pipe 8, so that the premixer 70 is convenient to clean and maintain.
As shown in fig. 2 and 3, the inside of the upper end of the gas flow divider 5 is a circular hollow cavity, the gas flow divider 5 is composed of 4 same cylindrical hollow pipes and a circular hollow cavity, which is beneficial to uniformly dividing air, specifically, the upper ends of the 4 cylindrical hollow pipes are respectively and uniformly distributed around the outer wall of the circular hollow cavity, and the upper ends of the 4 cylindrical hollow pipes are respectively and fixedly connected with the outer wall of the circular hollow cavity, so that the upper ends of the cylindrical hollow pipes are completely sealed with the outer wall of the circular hollow cavity, thereby avoiding the leakage of gas from the inside and avoiding unsafe accidents. The input of gas shunt 5 can be dismantled with the end of gas pipe 2 and be connected, and the output of gas shunt 5 (being the lower extreme of 4 cylindric hollow tubes promptly) can be dismantled with the input of premixer 70 and be connected, and this kind of connected mode provides convenience for overhauing, maintaining, washing and maintenance, has saved use cost.
Similarly, as shown in fig. 2 and 3, the inside of the upper end of the air splitter 6 is a circular hollow cavity, the air splitter 6 is composed of 4 same cylindrical hollow pipes and a circular hollow cavity, which is beneficial to evenly splitting air, particularly, the upper ends of the 4 cylindrical hollow pipes are respectively and evenly distributed around the outer wall of the circular hollow cavity, the upper ends of the 4 cylindrical hollow pipes are respectively and fixedly connected with the outer wall of the circular hollow cavity, so that the upper ends of the cylindrical hollow pipes are completely sealed with the outer wall of the circular hollow cavity, the phenomenon that air leaks from the inside to cause insufficient air volume is avoided, and insufficient combustion is achieved. The input of air shunt 5 and the terminal detachable connection of air pipe 4, the output (being the lower extreme of 4 cylindricality hollow tubes) of air shunt 5 and the detachable connection of the input of premixer 70, this kind of connected mode provides convenience for overhauing, maintaining, washing and maintenance, has saved use cost.
As shown in fig. 2 and 3, the gas splitter 5 is disposed outside the air splitter 6, because the safety level of the gas splitter 5 is higher than that of the air splitter 6, so that maintenance of the gas splitter 5 is facilitated. The output ends of the gas splitter 5 and the air splitter 6 are arranged in a staggered mode along the circumferential direction, so that gas and air are mixed more uniformly.
As shown in fig. 3 and 4, the premixer 70 is a disc-shaped cavity, the gas chamber 701 and the combustion air chamber 702 are provided inside the premixer 70, the gas chamber 701 and the combustion air chamber 702 are concentric closed isolated cavities, so that the gas and the combustion air are prevented from being mixed before entering the mixing chamber 71, the occurrence of uneven mixing is avoided, and the gas chamber 701 and the combustion air chamber 702 are coaxially staggered and uniformly arranged, so that the uniformity of secondary mixing is ensured. 4 imports have been seted up to gas chamber 701, and 4 imports of gas chamber 701 are connected with the lower extreme of 4 column hollow tubes of gas shunt 5 respectively, have realized the even reposition of redundant personnel's of gas mesh. 4 imports have been seted up to combustion-supporting air chamber 702, and 4 imports of combustion-supporting air chamber 702 are connected with the lower extreme of 4 column hollow tubes of air shunt 6 respectively, have realized the even reposition of redundant personnel's of combustion-supporting air purpose. The gas chamber 701 and the combustion-supporting air chamber 702 are not communicated with each other, and a partition plate is arranged in the middle for separating, so that the purpose of respectively shunting gas and combustion-supporting air is realized, the gas and the combustion-supporting air are prevented from being mixed before entering the mixing chamber 71, and the phenomenon of uneven mixing is avoided.
As shown in fig. 1, 5, 6 and 7, combustion system 11 comprises combustion cylinder 110 and fire barrier 12, wherein combustion cylinder 110 is covered with fire barrier 12 of uniform thickness, and the appropriate thickness of fire barrier is selected to further reduce NOx formation. Fire-retardant layer 12 cladding is on the outer wall top layer of a combustion section of thick bamboo 110, and fire-retardant layer 12 adopts specific refractory material to make for the combustion of a 110 surperficial combustible mixture of a combustion section of thick bamboo is more even, has the effect of stable combustion operating mode and control NOx emission. The combustion cylinder 110 is a cylindrical cylinder, a plurality of combustion holes 111 are uniformly formed in the circumference of the cylinder wall of the combustion cylinder 110, the combustion holes 111 are through holes, uniform combustion can be realized through the through holes, and convenience is brought to the realization of controlling the discharge amount of NOx. The combustion cylinder 110 is divided into a plurality of (4 in this embodiment) identical combustion chambers, and in the 4 combustion chambers, the same excess air coefficient is ensured at each part of the surface of the burner, thereby realizing the sufficient combustion of the mixed gas of the gas and the combustion air.
The control process of the gas pressure regulating valve 3 and the air pressure regulating valve 4 will be described below, specifically taking the boiler loads of 100%, 50%, 25%, and the abnormal state as examples:
step 1, after the air pressure regulating valve 4 receives a boiler load full-open (100% load) signal, the air pressure regulating valve 4 is opened to a full-open state, meanwhile, a signal is fed back to the gas pressure regulating valve 3, and the gas pressure regulating valve 3 is opened to a full-open state after receiving the signal. If the combustion cylinder 110 is normally combusted, a feedback signal is sent to the boiler, and the boiler enters a normal running state after receiving the feedback signal; if the combustion cylinder 110 is abnormal in combustion, a feedback signal of the abnormal combustion is sent to the boiler, the gas pressure regulating valve 3 is closed in parallel locking mode, purging is conducted in the boiler, and the air pressure regulating valve 4 is closed in a delayed mode.
And 3, receiving a boiler load (25%) opening degree signal by the gas pressure regulating valve 3, opening the gas pressure regulating valve 3 to a 25% opening degree state, delaying the opening of the associated air pressure regulating valve 4 to 25%, if the combustion cylinder 110 is normally combusted, sending a signal feedback of normal combustion to the boiler, enabling the boiler to enter a normal running state, if the combustion cylinder 110 is abnormally combusted, sending a signal feedback of abnormal combustion to the boiler, closing the gas pressure regulating valve 3 by a parallel lock, purging in the boiler, and delaying the closing of the air pressure regulating valve 4.
Through the mutual correlation control process of the gas pressure regulating valve 3 and the air pressure regulating valve 4, the low NOx premixing system 7 and the combustion system 11 can be automatically controlled, and the stability and the automation degree of the boiler operation and the boiler thermal efficiency are greatly improved while the NOx emission is reduced.
The denitration process of the fuel gas comprises the following steps: as shown in fig. 1 and 3, the gas enters from the gas pipe 2, passes through the gas pressure regulating valve 3, the gas pressure regulating valve 3 regulates the opening of the gas to control the load (pressure and flow) of the gas according to the requirement of the actual working condition load, the gas with a certain flow is conveyed to the gas flow divider 5 of the premixing system 7, primary flow division is carried out in the gas flow divider 5, the gas is averagely divided into 4 paths, and the gas respectively passes through 4 columnar hollow pipes of the gas flow divider 5 and enters the gas chamber 701 of the premixer 70 to be subjected to secondary flow division. Combustion air enters the air filter 1, pure combustion air is generated after the air filter 1 is filtered and enters the air pipe 40, the air pipe 40 conveys the pure combustion air to the air pressure adjusting valve 4, the air pressure adjusting valve 4 adjusts the pressure and the flow of the self-opening control combustion air according to the requirement of the load of the actual working condition, the combustion air with certain load is conveyed to the air splitter 6 of the premixing system 7, primary shunting is carried out in the air splitter 6, the combustion air is averagely divided into 4 paths, the combustion air respectively passes through 4 columnar hollow pipes of the air splitter 6, and the combustion air enters the combustion air chamber 702 of the premixer 70 to be subjected to secondary shunting. The gas enters the mixing chamber 71 after passing through the gas chamber 701, and the combustion air enters the mixing chamber 71 after passing through the combustion air chamber 702. In the mixing chamber 71, the gas forms the gas mixture after fully misce bene with combustion air, the gas mixture gets into mixed gas pipe 8, mixed gas pipe 8 carries the gas mixture to the air-blower 9 in, air-blower 9 carries the gas mixture compression back to stokehold takeover 10, the gas mixture carries out tertiary reposition of redundant personnel in 4 combustion warehouses of the combustion cylinder 110 of combustion system 11 after taking over 10 before the stokehold, combustible mixture after the cubic reposition of redundant personnel reaches abundant misce bene, fully burn in combustion cylinder 110, finally realize full production process, and reach the purpose that reduces the NOx emission.
It can be seen from the above that, gas and air carry out the one-level reposition of redundant personnel respectively at gas shunt 5 and air shunt 6, then carry out the second grade reposition of redundant personnel respectively in gas chamber 701 and combustion-supporting air chamber 702, mix in mixing chamber 71, carry out tertiary reposition of redundant personnel in 4 combustion warehouses of a combustion section of thick bamboo 110 at last, guaranteed to the at utmost that gas and combustion-supporting air are fully homogeneous mixing before the burning, realize full production process and reach the mesh of coming out of stock, a combustion section of thick bamboo 110 and spark arrester 12 make denitration efficiency obtain further improvement, NOx's emission standard has been reached.
A control method based on a full-premixing denitration system of a gas industrial boiler comprises the following steps:
step 1, confirming the normal running state of the boiler, and opening a gas pressure regulating valve 3 and an air pharmacology regulating valve 4.
And 3, opening the gas pressure regulating valve 3 and the air pressure regulating valve 4 according to the operation load state signal sent by the boiler.
And 4, if the boiler receives the abnormal combustion signal of the combustion cylinder 110, interlocking and closing the gas pressure regulating valve 3 to purge the interior of the boiler, and closing the air pressure regulating valve 4 in a delayed manner to perform a troubleshooting stage of the combustion cylinder 110.
By the control method, the automatic control of the whole system is realized by utilizing the gas pressure regulating valve 3 and the air pressure regulating valve 4, and the stability of the system operation and the thermal efficiency of the boiler are improved.
The present embodiment is only illustrative and not restrictive, and those skilled in the art can make modifications without inventive contribution as required after reading the present specification, but all of them are protected by patent laws within the scope of the present invention.
Claims (10)
1. The utility model provides a gas industry boiler full premix deNOx systems which characterized in that: the gas pressure control system comprises a gas pressure regulating valve (3), an air pressure regulating valve (4), a premixing system (7) and a combustion system (11), wherein the gas pressure regulating valve (3) is connected with one inlet of the premixing system (7), the air pressure regulating valve (4) is connected with the other inlet of the premixing system (7), and the premixing system (7) is connected with the combustion system (11); the premixing system (7) comprises a gas flow divider (5), an air flow divider (6), a premixer (70) and a mixing chamber (71); the gas flow divider (5) and the air flow divider (6) are respectively connected with the input end of the premixer (70), and the output end of the premixer (70) is fixedly connected with the input end of the mixing chamber (71); the combustion system (11) comprises a combustion cylinder (110) and a fire retardant layer (12), wherein the fire retardant layer (12) is coated on the surface layer of the outer wall of the combustion cylinder (110); a plurality of combustion holes (111) are uniformly formed in the circumference of the wall of the fire retardant layer (12).
2. The full premix denitration system of the gas industrial boiler of claim 1, characterized in that: the gas shunt (5) is composed of a columnar hollow pipe and a circular hollow cavity, and the upper end of the columnar hollow pipe is fixedly connected with the outer wall of the circular hollow cavity.
3. The full premix denitration system of the gas industrial boiler of claim 1, characterized in that: the air flow divider (6) is composed of a columnar hollow pipe and a circular hollow cavity, and the upper end of the columnar hollow pipe is fixedly connected with the outer wall of the circular hollow cavity.
4. The full premix denitration system of the gas industrial boiler of claim 1, characterized in that: a gas chamber (701) and a combustion-supporting air chamber (702) are formed in the premixer (70), and the gas chamber (701) and the combustion-supporting air chamber (702) are concentric circular closed isolation cavities.
5. The full-premix denitration system of the gas industrial boiler according to claim 4, characterized in that: the gas chamber (701) is provided with a plurality of inlets, and the inlets are respectively connected with the lower ends of the columnar hollow pipes of the gas splitter (5).
6. The full-premix denitration system of the gas industrial boiler according to claim 4, characterized in that: and the inlet of the combustion-supporting air chamber (702) is respectively connected with the lower end of the columnar hollow pipe of the air splitter (6).
7. The full-premix denitration system of the gas industrial boiler according to claim 4, characterized in that: the gas chamber (701) and the combustion air chamber (702) are not communicated with each other.
8. The full premix denitration system of the gas industrial boiler of claim 1, characterized in that: the interior of the combustion cylinder (110) is divided into a plurality of identical combustion chambers.
9. The full premix denitration system of the gas industrial boiler of claim 1, characterized in that: the surface of the combustion cylinder (110) is covered with a fire retardant layer (12) with uniform thickness.
10. The control method based on the full-premix denitration system of the gas industrial boiler as claimed in claim 1, characterized in that: the method comprises the following steps:
step 1, confirming the opening of the gas pressure regulating valve (3) and the air pressure regulating valve (4) when the boiler is in a normal running state;
step 2, internal and external monitoring: if the operation is abnormal, an alarm signal is sent out, the next operation is stopped, and the fault is checked and eliminated; if the operation is normal, continuing to perform the step 1 and then performing the next operation;
step 3, opening the gas pressure regulating valve (3) and the air pressure regulating valve (4) according to the load of the boiler;
and 4, if the abnormal combustion signal of the combustion cylinder (110) is received, closing the gas pressure regulating valve (3) in an interlocking manner, closing the air pressure regulating valve (4) in a delayed manner, and performing boiler internal purging and troubleshooting on the combustion cylinder (110).
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Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101297160A (en) * | 2005-07-26 | 2008-10-29 | 奥普莱米塞有限公司 | Method and installation for unsupported lean fuel gas combustion, using a burner and related burner |
| CN103742906A (en) * | 2013-12-30 | 2014-04-23 | 重庆广播电视大学 | Sleeve type gas combustor with electronic ignition device |
| CN206338801U (en) * | 2016-11-15 | 2017-07-18 | 广州威茨热能技术有限公司 | A kind of air-fuel premixed combustion system |
| CN109539251A (en) * | 2018-12-14 | 2019-03-29 | 罗诺克兹（北京）能源设备技术有限公司 | A kind of super low NO |
| CN109899786A (en) * | 2019-03-27 | 2019-06-18 | 苏州博墨热能产品有限公司 | Nonflame low NO and nonflame low nitrogen burning method |
| CN211450898U (en) * | 2019-10-29 | 2020-09-08 | 陕西工业职业技术学院 | Full-premixing denitration system of gas industrial boiler |
-
2019
- 2019-10-29 CN CN201911038636.4A patent/CN110822417B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101297160A (en) * | 2005-07-26 | 2008-10-29 | 奥普莱米塞有限公司 | Method and installation for unsupported lean fuel gas combustion, using a burner and related burner |
| CN103742906A (en) * | 2013-12-30 | 2014-04-23 | 重庆广播电视大学 | Sleeve type gas combustor with electronic ignition device |
| CN206338801U (en) * | 2016-11-15 | 2017-07-18 | 广州威茨热能技术有限公司 | A kind of air-fuel premixed combustion system |
| CN109539251A (en) * | 2018-12-14 | 2019-03-29 | 罗诺克兹（北京）能源设备技术有限公司 | A kind of super low NO |
| CN109899786A (en) * | 2019-03-27 | 2019-06-18 | 苏州博墨热能产品有限公司 | Nonflame low NO and nonflame low nitrogen burning method |
| CN211450898U (en) * | 2019-10-29 | 2020-09-08 | 陕西工业职业技术学院 | Full-premixing denitration system of gas industrial boiler |
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