CN114738786A - Sectional type gas torch combustion system - Google Patents

Abstract

The invention discloses a segmented gas torch combustion system, which comprises connecting an intake main pipe to a gas distribution pipe, the diameter of each branch gas pipe is determined according to the designed and distributed combustion gas volume of each level, and each is equipped with a manual valve corresponding to the diameter, The staging burner valve group composed of pneumatic or electric valves and flame arresters controls the combustion gas supply of the combustion heads of the corresponding staging burner nozzle tubes in the torch, which are independent and uniform. When each staging burner is put into use, the gas is ejected from the combustion head , burns after being ignited by the ignition light. The intake air volume is automatically adjusted according to the combustion gas volume and intensity. A part is evenly mixed with the gas ejected from the uniform combustion head to provide the required oxygen, and the remaining part is further mixed with the combustion flue gas to reduce the temperature of the exhaust flue gas and reduce the influence of thermal radiation. The burner can adapt to a wide range of changes in gas volume by grading the burners at all levels within a wide flow range, and can achieve stable, safe, smokeless combustion and meet the emission standards.

Description

A segmented gas flare combustion system

technical field

The invention belongs to the technical field of burners, and in particular relates to a segmented gas torch combustion system.

Background technique

By-product biogas will be produced in various anaerobic fermentation processes such as garbage disposal leachate, sewage treatment, livestock farm manure treatment, and biopharmaceuticals. The main component of biogas is methane, which is a greenhouse gas. According to environmental protection requirements, it is not allowed. directly discharged. The biogas with methane as the main component produced in the process of anaerobic treatment must use its thermal energy through combustion, or be burned by torches and then discharge up to the standard; there are other gases (natural gas, coal gas, liquefied gas, etc.) in the process of storage and transportation. There are also requirements for emergency combustion and discharge of excess gas; flare burners are the core equipment for flare combustion and emissions such as biogas and natural gas. At the same time, according to the requirements of GB/T41191-2021 "Flame Burners for Biogas Engineering", closed biogas flares are required to be burned during combustion. Under the condition that the volume adjustment ratio is not less than 5:1, the biogas torch will not produce open flames at the maximum pressure and flow rate. At the lowest rated pressure, the biogas torch can burn stably without tempering, and the biogas torch processing capacity should not be less than For peak gas production per hour, the temperature of the outer surface of the torch should not be higher than the ambient temperature of 60°C. This places higher demands on the biogas burner.

With the implementation of energy conservation, emission reduction and carbon neutralization policies, the awareness and requirements for comprehensive utilization of pollutants have been continuously improved, and the requirements for environmental protection emission standards have also been further improved. In recent years, biogas engineering projects have been significantly developed. With the improvement of anaerobic fermentation technology and the optimization of biogas collection technology, the production of biogas has been continuously improved, and the demand for biogas processing capacity and biogas processing capacity has been raised to a new level. Expanding, 1000+ square and larger flare handling requirements keep coming. New requirements are put forward for the flare burner, which requires the burner to have a larger combustion volume adjustment ratio, that is, to be able to burn stably and safely within a larger range of biogas volume, and meet the emission standards. Existing flare burners have a relatively narrow range of adaptation to gas volume, and are not well suited for large-flow gas flares, and there are many problems.

Existing torch burners all use a one-stage combustion method, that is, except for the permanent light, there is only one burner and valve group. Generally, the burner and valve group are configured according to the designed gas volume, resulting in the initial operation of the biogas project, due to the gradual investment of anaerobic fermentation. The operation and initial stage need to be adjusted and adjusted, the biogas volume is far below the designed gas volume, and the torch operation has the situation of big bull pulling the car, which often causes the ignition to fail or flame out, which cannot be continuously and normally and safely burned; it needs to rely on manual inspection to deal with it in time, and there is a potential safety hazard. ; Combustion can be gradually normalized only when the gas production in the later stage is close to the design gas amount; in the later stage, the amount of biogas is large, and it is prone to misfire, floating fire, incomplete combustion, etc. Another situation is that the actual gas production is due to various reasons. There is a big difference with the designed gas production, which will also affect the normal operation of the torch. In short, the torch cannot adapt to the change of gas volume, the applicable flow range is small, and the combustion volume adjustment ratio is small.

There are two air distribution modes for existing torches, one is to configure a fan to supply the air (oxygen) required for combustion to the torch through forced ventilation, and the other is to use a natural suction method to supply oxygen without a fan. From the actual usage of users, forced ventilation torches equipped with fans can still operate normally for torches with small gas volume. As the amount of biogas increases, the air required for torch combustion increases greatly, and the amount of torch gas discharged as emergency combustion is less than Changes are also constantly changing according to changes in the production process or emergencies. The air distribution capacity of the same fan is difficult to match in time with the change of biogas volume, resulting in too much air volume at the initial stage of ignition or re-ignition after flameout, which affects normal ignition and combustion. When the amount of biogas is large, the air distribution can not keep up, which will easily cause incomplete combustion, fail to meet the environmental protection emission requirements, and there are potential safety hazards.

Existing torch technologies all use one-way ignition lights and one-way flame detectors. For atmospheric torches, due to the large diameter of the torch barrel, the ambient wind direction and air volume during natural inhalation have a certain impact on the stability of the torch gas supply. When the amount is small, the fullness of the flame is small, and the ignition and flame detection all the way can not guarantee the timely and correct completion of ignition and flame detection, resulting in ignition failure or false alarm. Affect the normal and safe combustion operation of the torch.

Due to the relatively small scope of application of the existing flare burners for safe and stable combustion of biogas volume, sometimes the project is large, and the final gas production is constantly increasing. Large, complicated pipeline and control, the production and operation cost is greatly increased.

SUMMARY OF THE INVENTION

The purpose of the present invention is to provide a segmented gas flare combustion system to solve the problems existing in the prior art proposed in the above background technology.

To achieve the above object, the present invention has adopted the following technical solutions:

A segmented gas flare combustion system, comprising a flare;

and multiple groups of nozzles arranged in the torch, the multiple groups of the nozzles correspond to multi-stage burner valve groups;

It also includes a gas distribution pipe and a plc control system, the gas distribution pipe is connected with the multi-stage burner valve group, and the plc control system is used to control the gas distribution pipe to the multi-stage burner valve group and to the corresponding stages. The air supply volume of the multiple sets of nozzles of the burner.

Preferably, the multi-stage burner valve group includes: a first-stage burner valve group, a second-stage burner valve group, a third-stage burner valve group; the first-stage burner valve group, the second-stage burner valve group, The three-stage burner valve groups are all communicated with the gas distribution pipe.

Preferably, the first-stage burner valve group, the second-stage burner valve group, and the third-stage burner valve group include:

The staging burner intake pipe and the manual valve, pneumatic valve and flame arrester fitted on the staging burner intake pipe; the pneumatic valve is connected with the plc control system.

Preferably, the multiple groups of the nozzles include:

A staged burner riser and a combustion head nozzle tube connected to the staged burner riser; wherein the burner head nozzle tube communicates with the staged burner riser, and the staged burner riser is connected to a corresponding staged burner The intake pipe is connected.

Preferably, a biogas intake manifold is also included, and the biogas intake manifold communicates with the gas distribution pipe.

Preferably, multiple groups of igniters are also included, and the multiple groups of igniters are set corresponding to the multi-stage burners.

Preferably, the multiple groups of igniters include:

An ignition permanent lamp and a flame detector; an ignition gas source is connected to the ignition permanent lamp.

Preferably, the torch is provided with a shutter-type air inlet.

Technical effects and advantages of the present invention: a segmented gas flare combustion system proposed by the present invention has the following advantages compared with the prior art:

1. In the present invention, the main gas pipe is distributed through the gas distribution pipe, and the burner is divided into two-way or three-way graded burners, all of which are equipped with control valve groups, which are called primary burners, secondary burners, and tertiary burners. , The biogas combustion volume of each combustion head can be distributed and designed according to the possible production of biogas of the project and the convenience of switching the burners at all levels when the gas volume changes. Operation, with the increase of biogas volume, the secondary burner or tertiary burner is put into operation, or several stages of burners are burned at the same time, so that the combustion capacity of the torch matches the actual biogas volume, and staged (graded) combustion can be realized. The actual gas volume program control automatically starts or stops the burners at all levels, adapts to the combustion of different gas volumes, and the combustion is safe and stable.

2. The natural suction and automatic air distribution method are adopted, the air-fuel ratio is automatically adjusted, the flame is evenly dispersed, the flame is relatively short, the mixing is good, and the combustion flame is stable. There will also be no unsafe combustion conditions such as unstable combustion, incomplete combustion, and easy flameout, which may occur due to the mismatch between the air supply volume of the fan and the gas volume.

3. The staged and staged combustion technology is adopted to solve the combustion control and safety and reliability of large-flow torches at different gas volumes. One large-flow torch can be used to complete the gas combustion and emission requirements at different stages and different flows, and there is no need to set different gas volumes. Multiple torches reduce site space and equipment costs, greatly improve economy, save costs, and make the site more spacious and more convenient to control.

Description of drawings

Fig. 1 is the top view structure schematic diagram of the segmented gas flare combustion system of the present invention;

FIG. 2 is a schematic view of the front structure of the segmented gas flare combustion system of the present invention.

In the picture:

1. Torch; 2. Nozzle; 201. Staged burner standpipe; 202, Combustion head nozzle pipe; 3. Multi-stage burner valve block; 301, Primary burner valve block; 302, Secondary burner valve block; 303, three-stage burner valve group; 304, staging burner intake pipe; 305, manual valve; 306, pneumatic (or electric) valve; 307, flame arrester; 4, gas distribution pipe; 5, biogas intake manifold; 6 , igniter; 601, ignition light; 602, flame detector; 7, louvered air inlet.

Detailed ways

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, but not all of the embodiments. The specific embodiments described herein are only used to explain the present invention, and are not intended to limit the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

Example 1

The present invention provides a segmented gas torch combustion system as shown in Figures 1-2, including a torch 1;

And multiple groups of nozzles 2 arranged in the torch 1, the multiple groups of the nozzles 2 correspond to the multi-stage burner valve group 3; also include a gas distribution pipe 4 and a plc control system, the gas distribution pipe 4 and the multi-stage burner valve group 3; The stage burner valve group 3 is connected, and the plc control system is used to control the gas supply amount of the gas distribution pipe 4 to the multi-stage burner valve group 3 and the corresponding multiple groups of nozzles.

The multi-stage burner valve group 3 includes: a first-stage burner valve group 301, a second-stage burner valve group 302, and a third-stage burner valve group 303; the first-stage burner valve group 301, the second-stage burner valve group The group 302 and the three-stage burner valve group 303 are both communicated with the gas distribution pipe 4 . The first-stage burner valve group 301, the second-stage burner valve group 302, and the third-stage burner valve group 303 include:

Staged burner intake pipe 304 and manual valve 305, pneumatic (or electric) valve 306, and flame arrester 307 fitted on the staged burner intake pipe 304; the pneumatic (or electric) valve 306 is controlled with the plc system is connected.

The multiple groups of nozzles 2 include: a staged burner standpipe 201 and a combustion head nozzle tube 202 connected to the staged burner standpipe 201 ; wherein the burner head nozzle tube 202 is connected to the staged burner standpipe 202 201 is connected, and the staging burner standpipe 201 is communicated with the staging burner intake pipe 304 . It also includes a biogas intake manifold 5 that communicates with the gas distribution pipe 4 .

It also includes multiple groups of igniters 6 , and the multiple groups of igniters 6 are provided corresponding to the multi-stage burners 3 . The igniter 6 includes: an ignition permanent lamp 601 and a flame detector 602; an ignition gas source is connected to the ignition permanent lamp 601. The torch 1 is provided with a shutter-type air inlet 7 .

Example 2

The technical route of the segmented gas flare combustion system in this embodiment is to design the flare burner into segments and adopt a staged combustion method, that is, the flare burner is designed into two or three through the gas distribution pipe, which can operate independently and Two-stage or three-stage flare burners that can be operated in combination, and the nozzles of each branch flare burner are evenly distributed in the flare barrel. The start and stop of the flare burners at all levels can be controlled by the program and put into operation in stages according to the change of the gas volume, or it can be manually started and stopped.

The composition of the segmented flare burner, the main intake pipe is connected to the gas distribution pipe set before the torch, and the gas is divided into two or three-way staging burner intake pipes through the gas distribution pipe, and the diameter of each staging burner intake pipe is According to the size of the gas volume of the project that may be put into production in stages and the convenience of seamless switching of burners at all levels when the gas volume changes, the distribution design is carried out, so that all gas volume ranges can be conveniently put into operation in stages, and operate smoothly and safely. The sum of the design flow of all the staged burners is to meet the requirements of the total designed combustion capacity of the flare when they are all put into operation.

The intake pipe of each staged burner is equipped with a corresponding caliber torch control valve group (including manual valve, electric or pneumatic control valve, flame arrester). The head nozzle tube, the combustion head of each stage burner is evenly distributed in the torch, and the gas supply and combustion of the corresponding combustion head are controlled by the valve group, that is, a two-stage or three-stage burner is formed.

In order to meet the requirements of different working conditions and changes in flare gas flow, the flare adopts staged combustion and automatic staged control and is put into operation. That is, the burners are divided into multi-stage combustion systems according to different conditions such as the amount of exhaust gas and accidental emissions. It ensures that good combustion and smoke elimination effects can be obtained even when the exhaust gas flow is small. As the exhaust gas flow increases, it is controlled by the pressure of the exhaust gas. After reaching the control value, the burners at all levels are gradually put into operation or stopped. That is to say, when the basic conditions for torch combustion and ignition are met, the first-stage burner is started first when the exhaust gas volume is small, and the gas is ejected through the first-stage burner and ignited by the flame of the ever-bright lamp. Start the secondary burner, and as the gas volume further increases, start the tertiary burner according to the program, or start two or three combined combustion of the first, second and third stage burners at the same time, using PLC to achieve efficient automatic Hierarchical control, the exhaust gas flow adapts to a wide range, the gas flow can achieve high-efficiency smokeless combustion from zero to the maximum amount of emergency discharge, and the system has high safety. Each stage of the burner is equipped with an ignition permanent light and a flame detector, and the ignition gas source is controlled by an ignition solenoid valve or a pneumatic valve. Safety. The permanent light is equipped with an automatic ignition device, that is, when the permanent light is extinguished due to external factors, the permanent light can be automatically re-ignited to ensure the reliability of torch ignition.

The segmented torch adopts the natural suction and automatic air distribution method of the shutter, and the hot flue gas generated by the torch combustion is discharged from the top of the torch, thus forming a certain negative pressure in the combustion area, so that the outside air can be automatically drawn from the shutter at the bottom of the torch. A steady stream of air flows into the flare to ensure sufficient air volume for the exhaust gas to burn. The air suction volume has a corresponding relationship with the amount of hot flue gas discharged from the top of the torch. On the one hand, the air entering the torch cooperates with the uniformly distributed torch combustion head with a special structure, so that the exhaust gas and air can be optimally mixed, so as to achieve smokeless combustion On the other hand, the excess air is further mixed with the flue gas to effectively reduce the exhaust temperature of the flue gas and greatly reduce the heat radiation ability of the flue gas to the surrounding environment. At the same time, since the combustion flame of the exhaust gas and the high temperature area of combustion are enclosed in the combustion chamber of the torch body, the leakage of the heat radiation of the combustion flame is avoided, so the fire light cannot be seen outside, and the flame heat radiation cannot be felt.

The biogas intake main pipe enters the gas distribution pipe set before the torch, and the main gas pipe is divided into two or three-way staged burner branch pipes according to the design requirements through the gas distribution pipe. Each burner branch pipe is equipped with manual valve, pneumatic or electric valve. The burner valve groups at all levels composed of flame arresters control the injection volume of biogas in the nozzle tubes of the burner combustion head installed on the burner standpipe behind, so as to control the combustion of the burners at all levels.

The segmented flare burner is provided with a set of ignition valve groups. The ignition gas source can be high calorific value gas such as natural gas, or directly used biogas or other exhaust gas. The ignition valve group is used to control the ignition of the permanent lamp.

The segmented torch burner is equipped with 2 or 3 sets of ignition lights and flame detectors, all lights are ignited at the same time, the flame detector detects whether there is fire burning, and the lights are kept burning under normal conditions, so that there is a torch at any time Air exhaust can be ignited in time to ensure the safety of the system. The permanent light is equipped with an automatic ignition device, that is, when the permanent light is extinguished due to external factors, the permanent light can be automatically re-ignited to ensure the reliability of torch ignition.

The torch is equipped with natural air inlet shutters. Since the flue gas is discharged to the top after the torch is burned, it has the effect of chimney exhaust. The more flue gas is discharged, the greater the negative pressure at the lower part of the combustion head, and the more air is sucked in from the lower part of the torch. According to the gas in the torch The combustion volume automatically absorbs the required air volume through the shutter, and the air distribution is stable. Part of the air distribution is mixed with gas to provide the required combustion air volume, and the excess part is mixed with high-temperature flue gas to reduce the temperature of the exhaust flue gas, reduce the temperature of the outer surface of the torch, and reduce the impact of thermal radiation on the environment.

In this embodiment, the structure of the 4500-cubic segmented flare burner is taken as an example:

Ignition gas source adopts DN50 pipeline for torch combustion ignition gas source pipe (manual/automatic, ignition and flameout procedure), designed to use natural gas with high calorific value or directly use exhaust gas such as biogas, and the gas consumption is 4Nm3/h.

The branch pipe of the first stage burner adopts DN150 pipe, and the pressure is controlled for combustion (manual/automatic, ignition and flameout procedures are set), and the designed normal emission is 750Nm3/h, and the fluctuating emission is 400-900Nm3/h.

The branch pipe of the second stage burner adopts DN200 pipe, and the pressure is controlled for combustion (manual/automatic, ignition and flameout procedures are set), and the designed normal emission is 1500Nm3/h, and the fluctuating emission is 800-1800Nm3/h.

The branch pipe of the third-stage burner adopts DN250 pipe, and the pressure is controlled for combustion (manual/automatic, ignition and flameout procedures are set).

In this embodiment, three-way ignition lights and flame detectors are separately installed from the ignition gas source DN50 main pipe through the control valve group to ensure stable ignition and stable ignition and combustion of the burners at all levels, without the phenomenon of flame failure and flameout.

In this embodiment, the natural air suction structure of the shutter is used to provide the air required for combustion.

The torch operation is controlled by PLC. According to the change of the exhaust gas volume, the primary, secondary and tertiary burners are automatically controlled to start or stop the combustion operation respectively, and they are automatically switched and put into operation. It can operate stably and safely under the designed gas volume of 4,500 cubic meters. It solves the combustion control and safety and reliability of large-flow torches at different gas volumes. One large-flow torch can be used to meet the needs of gas combustion and emissions at different stages and different flows. It is not necessary to set up multiple torches with different gas volumes, reducing site space. Equipment costs, greatly improve the economy, save costs, the site is also more spacious, more convenient control.

Finally, it should be noted that the above descriptions are only preferred embodiments of the present invention, and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, for those skilled in the art, the The technical solutions described in the foregoing embodiments can be modified, or some technical features thereof can be equivalently replaced, and any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included. within the protection scope of the present invention.

Claims (8)

1. A segmented gas torch combustion system, characterized in that it comprises a torch (1); and multiple groups of nozzles (2) arranged in the torch (1), the multiple groups of the nozzles (2) corresponding to multiple A stage burner valve group (3); further comprising a gas distribution pipe (4) and a plc control system, the gas distribution pipe (4) is connected with the multi-stage burner valve group (3), the plc control system The gas distribution pipe (4) is used to control the gas supply volume of the corresponding multiple groups of nozzles (2) through the multi-stage burner valve group (3). 2. A segmented gas flare combustion system according to claim 1, characterized in that: the multi-stage burner valve group (3) comprises: a primary burner valve group (301), a secondary burner Valve group (302), three-stage burner valve group (303), the number of burner stages can be 2-4 according to the amount of gas; the first-stage burner valve group (301), the second-stage burner valve group (302) and the three-stage burner valve group (303) are all communicated with the gas distribution pipe (4), and are communicated with corresponding groups of nozzles (2) respectively. 3. A segmented gas flare combustion system according to claim 2, characterized in that: the first-stage burner valve group (301), the second-stage burner valve group (302), and the third-stage burner valve The group (303) includes: a staged burner intake pipe (304) and a manual valve (305), a pneumatic valve (306), and a flame arrester (307) fitted on the staged burner intake pipe (304); The pneumatic valve (306) is connected with the plc control system. The segmented gas flare combustion system according to claim 3, characterized in that: the multiple groups of the nozzles (2) comprise: a branch burner riser (201) and a branch burner riser (201) Combustion head nozzle pipes (202) connected; wherein, the combustion head nozzle pipes (202) are communicated with the staging burner standpipes (201), and the staging burner standpipes (201) are connected with The intake pipe (304) is communicated. 5. A segmented gas flare combustion system according to claim 1, characterized in that it further comprises a biogas intake manifold (5), the biogas intake manifold (5) and the gas distribution pipe (4). ) are connected. 6. A segmented gas flare combustion system according to claim 1, characterized in that it further comprises multiple groups of igniters (6), the multiple groups of igniters (6) corresponding to the multi-stage burners (3) set up. 7 . The segmented gas flare combustion system according to claim 6 , wherein the multiple groups of igniters ( 6 ) all comprise: an ignition long light ( 601 ) and a flame detector ( 602 ); the An ignition gas source is connected to the ignition permanent light (601). 8 . The segmented gas torch combustion system according to claim 1 , wherein the torch ( 1 ) is provided with a shutter-type air inlet ( 7 ). 9 .

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