CN203116011U

CN203116011U - Bottom combustor for cracking furnace with ultralow NOx emission

Info

Publication number: CN203116011U
Application number: CN 201320044213
Authority: CN
Inventors: 李金科; 张建
Original assignee: China Petroleum and Chemical Corp; Tianhua Institute of Chemical Machinery and Automation Co Ltd
Current assignee: China Petroleum and Chemical Corp; Tianhua Institute of Chemical Machinery and Automation Co Ltd
Priority date: 2013-01-27
Filing date: 2013-01-27
Publication date: 2013-08-07
Anticipated expiration: 2023-01-27

Abstract

The utility model discloses a bottom combustor for a cracking furnace with ultralow NOx emission which is mainly composed of a secondary combustor, an incandescent light, a moisture spray head, an air regulator, a primary combustor and a burner block. The bottom combustor for the cracking furnace with ultralow NOx emission is characterized in that the moisture spray head is arranged in a combustion air runner of the burner block, the moisture spray head can spray water or steam into a combustion area to reduce temperature of a burning flame, and classification fuel combustion and smoke recycling technology are combined to reduce NOx generation amount. The bottom combustor is high in operation stability, can form a long flame and achieves large-capacity combustion and ultralow NOx emission.

Description

A kind of pyrolysis furnace base burning device of ultralow NOx discharging

Technical field

The utility model relates to a kind of pyrolysis furnace base burning device of ultralow NOx discharging, and particularly a kind of is the bottom gas burner of the big ability of fuel, long flame, ultralow NOx discharging with fuel gas, is applicable on the ethane cracking furnace.

Background technology

Fuel gas with burn after air mixes, the hydrocarbon in airborne oxygen and the fuel gas carries out combustion reaction and emits a large amount of heat.But when burning under the condition of high temperature, oxygen excess, airborne nitrogen will react with airborne oxygen and generate heating power type NOx.As everyone knows, when in air, burning, can suppress heating power type NOx growing amount by controlling oxygen concentration, ignition temperature and the time of staying.NOx is the material that environment is had harm, it has been generally acknowledged that the discharging of NOx is relevant with minimizing and other environmental problems of ozone.

The low NOx combusting technology that uses mainly contains three kinds at present.First kind is air classification, makes combustion air shunt to set up first combustion zone of oxygen deprivation, thereby reduces the formation of NOx, in second combustion zone air of remainder is introduced, thereby is finished whole combustion process.Second kind is fuel staging, and combustion air is once all introduced first combustion zone, but has only part of fuel burned in first combustion zone, and remaining fuel is introduced in second combustion zone, utilizes the oxygen of the first combustion zone surplus to burn.In this burner, the air of the first combustion zone surplus has diluted fuel, and ignition temperature is lower, thereby reduces the formation of NOx.The third is flue gas recirculation, and the low-pressure area that utilizes combustion air or fuel gas stream to produce makes flue gas recirculation in the combustion zone, and inertia flue gas cooling flame reduces partial pressure of oxygen, thereby reduces the formation of NOx.

The technology in early stage and burner are being obtained success in various degree aspect the reduction NOx discharging, but the harshness day by day along with environmental requirement, need a kind of improved low-NOx combustor and method especially, it is also uncomplicated in design, has the high combustion ability, can outside satisfying many requirements such as flame profile, flame diameter, heat flow density distribution and regular maintenance, further reduce the NOx discharging.

CN202328231U discloses a kind of gas burner of the low-nitrogen oxide discharging for pyrolysis furnace bottom, mainly formed by entrance air channel, air channel, accent windshield plate, bellows, burner block, one-level burner, two stage burner, altar lamp, it is characterized in that burner block places the stove bottom, the boring place is the combustion air runner, be a runner that cross-sectional area is constant at its entrance, the cross-sectional area of outlet section diminishes gradually, form the air contracted channel, at this moment cross section and internal face angulation β; One-level fuel nozzle and secondary fuel shower nozzle are around the upper outside of burner block.The fuel gas of the one-level fuel nozzle ejection of one-level burner is injected in the side path of burner block, thereby attracts flue gas to enter the combustion air runner of burner block, utilizes flue gas recirculation to reduce the NOx growing amount.This pyrolysis furnace bottom gas burner is adapted at using as the base burning device in the ethane cracking furnace, can form flat flame, realizes big ability burning and low NOx drainage.But its combustion flame does not use more physical cooling method, and the NOx discharging also has the space that further reduces.

The utility model content

The purpose of this utility model is to provide a kind of bottom gas burner that is applicable to the big ability of ethane cracking furnace, long flame, ultralow discharged nitrous oxides, it is obtaining good flame profile, the length of flame, flame rigidity and heat flow density distribution simultaneously, and discharged nitrous oxides is lower.

The purpose of this utility model is achieved in that a kind of pyrolysis furnace of ultralow discharged nitrous oxides base burning device, mainly formed by two stage burner, altar lamp, steam shower nozzle, air register, one-level burner, burner block, it is characterized in that burner block places the stove bottom, the boring place is the combustion air runner, be furnished with steam shower nozzle and altar lamp respectively, steam shower nozzle injection water or steam enter the combustion zone, reduce combustion flame temperature.

When ejection medium was water, steam shower nozzle head construction preferably adopted the mechanical atomization pattern.The mass flow of steam shower nozzle 3 injection waters or steam is preferably 10%～100% of fuel gas mass flow.

The utility model is not determined the position of steam shower nozzle in the combustion air runner especially, can design according to the concrete structure of bottom gas burner, when using the utility model, preferably adopt computational fluid dynamics (CFD) method to carry out the design of burner block air flow channel; Adopt computational fluid dynamics (CFD) method to determine quantity, layout and the orientation of fuel jet orifice and steam spray orifice, thereby obtain gratifying flame profile and heat flux distribution.

The utility model provides big ability, a low-NOx combustor that is used for the cracking of ethylene furnace bottom, compares with low-NOx combustor with present pyrolysis furnace, and the NOx discharging is lower; And, burner of the present utility model safeguard and control on simpler, the operator who allows pyrolysis furnace optimize and stable heat flux characteristics under operate, be specially adapted on the ethane cracking furnace.

Other and further target of the present utility model, feature and advantage are by being described further in the following specific embodiment and the accompanying drawing.

Description of drawings

Fig. 1 is the front view of the utility model burner;

Fig. 2 is the vertical view of the utility model burner.

The specific embodiment

Shown in Figure 1 is a kind of big ability for ethane cracking furnace of the present utility model, long flame, ultralow NOx discharging bottom gas burner used, and mainly is made up of two stage burner 1, altar lamp 2, steam shower nozzle 3, air register 4, one-level burner 5, burner block 6.It only is a kind of form of the present utility model, and the utility model is not limited in this.

Consult Fig. 1, Fig. 2, be furnished with steam shower nozzle 3 in the combustion air runner 7 of burner block 6, steam shower nozzle 3 head constructions adopt the mechanical atomization pattern.

Consult Fig. 1, Fig. 2, the mass flow of steam shower nozzle 3 injection waters is 20% of fuel gas mass flow.

Consult Fig. 1, Fig. 2, the design of burner block air flow channel adopts the computational fluid dynamics method to carry out.

The design of the steam spray nozzle among Fig. 1, Fig. 2, layout, quantity and orientation adopt computational fluid dynamics (CFD) method to design.

Embodiment can also be the improvement of CN202328231U, except using classification fuel combustion and flue gas recirculating technique, also adopt in the combustion air runner of burner block and be furnished with the steam shower nozzle, the method of injection water or steam in the flame, utilize evaporation of water latent heat and steam that flame temperature is reduced, also can cause the reduction of oxygen, nitrogen partial pressure simultaneously, further reduce the NOx growing amount.

Claims

1. the pyrolysis furnace base burning device of a ultralow NOx discharging, mainly formed by two stage burner, altar lamp, air register, one-level burner, burner block, it is characterized in that burner block places the stove bottom, the boring place is the combustion air runner, be furnished with the steam shower nozzle, steam shower nozzle injection water or steam enter the combustion zone, reduce combustion flame temperature, further reduce the NOx discharging.

2. according to the pyrolysis furnace base burning device of the described a kind of ultralow NOx discharging of claim 1, it is characterized in that steam shower nozzle head construction adopts the mechanical atomization pattern.