CN1189385C - Burning nozzle with inner distributor and three jets for oxidizing natural gas partially to produce synthetic gas - Google Patents

Abstract

The present invention discloses a burner nozzle with an inner distributor and three nozzles for preparing synthetic gas through partial oxidation of natural gas. The burner nozzle is mainly composed of a center spray head, an inner ring gap spray head, an outer ring spray head, the inner distributor and a cooling system which are in combined installation; gasifying agents enter a center guide tube from an inlet tube, and then enter a passage formed by the inner ring gap spray head and the center spray head through a vertical hole arranged on the inner distributor; after being accelerated, the gasifying agents are sprayed from an inner ring gap nozzle; natural gas enters an outer guide tube from the inlet tube; one part of the natural gas enters the center spray head through an inclined hole arranged on the inner distributor and is sprayed from a center nozzle after being accelerated; the other part of the natural gas directly enters the passage formed by the inner ring gap spray head and the outer ring spray head, and is spayed from an outer ring nozzle. Because two parts of natural gas are formed at the nozzle of the burner nozzle for clamping the flowing state of the gasifying agents, the gasifying agents and the natural gas are promoted to be rapidly and uniformly mixed; thereby, the conversion rate of the natural gas, and the effective gas content at the outlet of a gasification furnace are increased; through increasing the gas flow rate and reducing the convergence angle of nozzles, the combustion intensity at the upper part of the gasification furnace is decreased; additionally, the arrangement of the cooling system well protects the burner nozzle and prolongs the service life of the burner nozzle.

Description

Three-port natural gas partial oxidation to synthesis gas burner with inner sparger

Technical field

The invention relates to a burner for producing synthetic gas (CO+H2) through partial oxidation of natural gas as raw material.

Background technique

The raw material of partial oxidation synthesis gas is generally residual oil or coal water slurry, but with the rise of global crude oil prices and the development of residual oil deep processing technology, the supply of residual oil is in short supply, and the price rises accordingly. The production of synthetic gas with residual oil as raw material (for the production of synthetic ammonia, methanol, and acetic acid) costs have also increased, and the adjustment of raw material routes is imperative. The discovery of large reserves of natural gas fields in western my country and the establishment of a west-to-east gas pipeline network have made it possible for the residual oil-based ammonia plants within the radiation radius to switch to natural gas. The key is to change the raw residual oil burner into a natural gas burner. For this reason, Texaco Company once provided a kind of natural gas burner with two nozzles for the transformation of a domestic factory, but the practice shows that the burner has the following problems:

(1) The upper part of the gasifier has a high combustion intensity, which causes overheating of the furnace top and affects the life of the gasifier;

(2) The conversion rate of methane (CH ₄ ) is low, and CH ₄ in the gasifier outlet gas is >1.0%, resulting in a decrease in the utilization rate of raw natural gas and causing troubles for the subsequent processing sections.

In view of the above-mentioned shortcomings of the existing technology, the production plant urgently hopes that scientific researchers can improve the existing burners for partial oxidation of natural gas to synthesis gas and provide a burner with better performance for partial oxidation of natural gas to synthesis gas.

The purpose of the present invention is to overcome the shortcomings of the prior art. The inventor has designed a three-nozzle natural gas partial oxidation synthesis gas burner with an internal distributor. It has good mixing performance, high natural gas conversion rate, and a gasifier. The advantages of moderate combustion intensity in the upper part can meet the requirements of relevant manufacturers for natural gas burners.

Contents of Invention

The concept of the present invention is as follows. The inventor has been engaged in gasification technology research for a long time and found that the advantages and disadvantages of the natural gas partial oxidation to synthesis gas technology mainly depend on the structural characteristics of the burner and the matching of the burner and the furnace body. Flow field characteristics.

The partial oxidation process of natural gas is usually carried out at high temperature (1200-1450°C), and the chemical reaction speed is extremely fast. The entire gasification process is controlled by mixing, and the mixing process is completely determined by the characteristics of the burner. In other words, the mixing performance of the burner The advantages and disadvantages of the furnace and the characteristics of the flow field formed by matching with the furnace determine the effect of the natural gas gasification process.

The invention automatically divides the natural gas into two streams through the internal distributor placed inside the burner, one stream goes to the center nozzle of the burner, the other goes to the outer ring nozzle of the burner, and the oxygen is burned through the round hole of the distributor The inner ring gap nozzle between the nozzle center nozzle and the outer ring nozzle, as well as the improvement (reduction) of the shrinkage angle of the burner nozzle and the setting of the cooling coil outside the burner head, these improvements of the burner have produced significant technical effects: ( 1) The mixing effect of natural gas and oxygen is greatly improved, the utilization rate of natural gas is increased, the methane content at the outlet of the gasifier is reduced, and the yield of effective gas (CO+H2) is increased. (2) Avoid local overoxygen, reduce the combustion intensity of the upper part of the gasifier, and prevent the furnace top from overheating. (3) It is beneficial to prolong the life of the burner.

The present invention is achieved in this way. The inventor has designed a three-nozzle natural gas partial oxidation synthesis gas burner with an inner distributor according to the above-mentioned concept, which consists of a central nozzle, an inner ring gap nozzle, an outer ring nozzle, and an inner distributor. , a concentric three-nozzle burner composed of various parts of the cooling system, wherein,

The center nozzle, which is fixedly connected with the inner distributor through mechanical cooperation, communicates with the outer ring conduit of the burner through the evenly distributed inclined holes on the inner distributor; the inner contraction half angle α of the center nozzle is 10°～45°, and its The lateral inclination angle β is 30°～80°; the center nozzle maintains the concentricity with the inner ring gap nozzle by means of the inner distributor.

Inner ring gap nozzle, which is fixedly connected with the inner distributor through mechanical cooperation, and communicates with the central duct of the burner through the uniformly distributed axial straight holes on the inner distributor; there is a connecting flange on the top of the central duct. It is fixedly connected with the connecting flange on the outer ring conduit, and a gasifying agent inlet pipe is arranged on the upper part of the central conduit, and a connecting flange is also arranged above the gasifying agent inlet pipe, by means of which it is connected with the gasifying agent pipeline The inner contraction half angle γ of the inner annular gap nozzle is 10°~45°; the outer inclination angle τ of the inner annular gap nozzle is 30°~80°; the inner annular gap nozzle maintains the concentricity with the center nozzle by means of the inner distributor .

The outer ring nozzle is fixedly connected with the outer ring conduit through mechanical cooperation; there is a connecting flange on the top of the outer ring conduit, which is used to cooperate with the connecting flange on the central conduit; on the upper part of the outer ring conduit There is a raw material inlet pipe, and there is also a connecting flange under the raw material inlet pipe, which is used for solid connection with the flange on the shell of the gasifier; the inner shrinkage half angle ε of the outer ring nozzle is 10° to 45°.

The inner distributor is placed inside the burner and plays the role of natural gas distribution. It is processed by forgings. The upper part is fixedly connected with the center pipe of the burner through mechanical cooperation, and the lower part is fixed with the center nozzle and the inner ring gap nozzle through mechanical cooperation. ; There is an axial straight hole on the distributor, and the gasification agent enters the inner ring gap nozzle through the axial straight hole through the central channel; there is also an inclined hole on the distributor, and a stream of natural gas enters through the inclined hole through the outer channel of the burner Inside the center nozzle; there is a flange on the outside of the distributor to maintain the concentricity between the outer ring nozzle and the inner ring gap nozzle.

The cooling system is mainly composed of a cooling chamber and a coiled pipe. The cooling liquid enters the cooling chamber from the cooling liquid inlet pipe, and then is discharged from the cooling liquid outlet pipe after passing through the coiled pipe. The space formed by the side, the transition flange and the end face; the coiled pipe is arranged outside the lower half of the burner; the cooling liquid is water or other safe liquid.

The so-called central conduit refers to the internal flow space of the burner that is connected to the distributor inside and the oxygen pipeline to the outside; the outer conduit is the space where the burner is connected to the natural gas pipeline and used for natural gas.

The top of the central conduit is an elbow, which is connected to the gasification agent pipeline through the flange on the elbow, and a connecting flange is provided under the elbow to help the central conduit and the top flange of the outer conduit to be fixedly connected.

The outer conduit and the outer ring nozzle are fixed after mechanical cooperation; the top of the outer conduit is provided with a connecting flange to help it cooperate with the connecting flange on the central conduit; the upper part of the outer conduit is provided with a raw material (natural gas) inlet pipe , connected to the natural gas pipeline through the flange; the lower part of the outer conduit is provided with a connecting flange, which helps it to be firmly connected to the flange on the shell of the gasifier.

The said internal distributor is placed inside the burner and plays the role of natural gas distribution. It is processed by forging. Rear connection. There is a vertical hole on the distributor, and the gasification agent (oxygen) enters the nozzle in the inner annular gap through the vertical hole through the central conduit of the burner; there is also an oblique hole on the distributor, and a stream of natural gas enters the center through the oblique hole through the outer conduit of the burner. nozzle.

The concentricity of the center nozzle and the inner ring gap nozzle is guaranteed by the inner distributor, and the concentricity between them and the outer ring nozzle is guaranteed by the finished flange on the outside of the distributor, that is, the outer arc of the flange Cooperate with the cylindrical surface inside the outer ring nozzle to maintain concentricity.

In order to protect the burner, a cooling chamber is installed outside the burner head, and a cooling coil is installed outside the outer ring nozzle. The cooling liquid (generally water) is introduced into the cooling chamber from the inlet pipe, and discharged from the outlet pipe after passing through the coil.

Said gasification agent is air or oxygen-enriched air with an oxygen content greater than 21% or oxygen with an oxygen content greater than 98%, depending on specific process requirements.

The flow velocity of the gasification agent at the nozzle is 10-300m/s, and the flow velocity of natural gas at the nozzle is 10-300m/s; for liquid raw materials, the flow velocity at the nozzle is 0.1-20m/s; the oxygen in the gasification agent The ratio to the carbon in the raw material (including natural gas or other liquid raw materials) is 0.50-1.60 Nm ³ /kg; the applicable pressure of the burner is 0.5-12.0 MPa.

The material of the center nozzle, inner ring gap nozzle, outer ring nozzle, cooling chamber, cooling coil, and inner distributor is stainless steel, and it can also be high temperature resistant Inconel 600; the inner and outer conduits of the burner are generally made of stainless steel. .

The burner of the present invention can not only use natural gas as raw material to produce synthesis gas, but also can use naphtha, diesel oil, heavy oil, residual oil, asphalt and other hydrocarbons or combustible materials to produce synthesis gas.

In addition, the burner of the present invention is also suitable for the production of reducing gas.

Description of drawings

Further illustrate content of the present invention below in conjunction with accompanying drawing:

Figure 1 is a front view of the appearance of a three-nozzle natural gas burner with an internal distributor.

Figure 2 is a cross-sectional view of part A-A of a three-port natural gas burner with an internal distributor.

in:

1——The three-nozzle natural gas burner is mainly composed of a central nozzle, an inner ring gap nozzle, an outer ring nozzle and an inner branch nozzle.

Composed of fabrics;

2——Cooling system, which is mainly composed of cooling chamber (23), cooling liquid inlet pipe (3), cooling liquid outlet pipe

Mouth pipe (5) and serpentine pipe (4) constitute;

3—coolant inlet pipe, one end of it communicates with the cooling chamber (23);

4—coil pipe, which is wound around the outside of the burner, one end communicates with the cooling chamber (23), and the other end communicates with the cooling chamber (23).

The coolant outlet pipe (5) is connected;

5——the cooling liquid outlet pipe, which is connected with the snake pipe (4);

6——connecting flange, which is fixedly connected with the flange on the gasifier;

7——Raw material inlet pipe, from which the raw material enters the burner outer ring conduit (12);

8——Gasification agent inlet pipe, from which the gasification agent enters the burner central conduit (11);

9 - connecting flange;

10 - connecting flange;

11——burner central conduit;

12——outer ring catheter;

13 - connecting flange;

14 - connecting flange;

15——central passage, the gasifying agent passage formed by the burner central conduit (11);

16——outer channel, the natural gas formed by burner outer ring conduit (12) and central conduit (11)

aisle;

17——Inner distributor, the upper end is fixedly connected with the central conduit (11), and the lower end is connected with the central nozzle

(20) is fixedly connected with the inner ring gap nozzle (21), while ensuring that the center nozzle and the inner ring gap nozzle

Concentricity between heads;

18——The axial straight hole of the inner distributor communicates with the center channel (15) and the inner annular gap nozzle (21a);

19——the oblique hole of the inner distributor communicates with the outer channel (16) and the center spout (20a);

20——Central nozzle, the upper end is fixedly connected with the inner distributor;

20a——center spout;

21——Inner ring gap nozzle, the upper end is fixedly connected with the inner distributor;

21a——inner annular gap nozzle;

22—the outer ring nozzle, the upper end is fixedly connected with the outer ring conduit (12);

22a——outer ring nozzle;

23——cooling chamber, it is positioned at the outer end of outer ring nozzle, is by the outer surface (24) of outer ring nozzle,

The annular space formed by the transition flange (25) and the end surface (27) is respectively provided with

There are coolant inlets (26) and corresponding outlets [symmetrical to (26), not shown in the figure],

And guide the cooling liquid through the coolant inlet pipe (3) and the annular coil pipe (4) on it respectively

The entry and exit of coolant;

24 - the outer surface of the outer ring nozzle;

25——transition flange, which is fixed on the outer surface of the outer ring nozzle;

26——cooling liquid inlet, set on the transition flange (25), and its other end is connected with the cooling liquid inlet

The pipes (3) are connected, and the coolant outlet (not

  the number shown in the figure), the other end of which is connected to the snake tube (4);

27——the end face, fixedly connected on the outer ring nozzle (22);

28 ---flange, it is arranged on the outside of inner distributor, guarantees that outer ring nozzle (22) and inner

Concentricity between annular nozzles (21);

α——Inner contraction half angle of the center nozzle;

β——Inclination angle outside the center nozzle;

γ——Inner contraction half angle of nozzle in inner annular gap;

τ—the inclination angle of the outer side of the nozzle in the inner ring gap;

ε——The inner contraction half angle of the outer ring nozzle.

The gasification agent enters the central channel (15) from the gasification agent inlet pipe (8), and enters the inner annular gap nozzle (21) through the axial straight hole (18) on the inner distributor (17) to form a center nozzle (20) The channel is ejected from the inner annulus nozzle (21a) after the speed is increased; the natural gas enters the outer channel (16) from the raw material inlet pipe (7), and one stream enters the center through the inclined hole (19) on the inner distributor (17) In the nozzle (20), it will be ejected from the center nozzle (20a) after speeding up; the other stream will directly enter the channel formed by the inner ring gap nozzle (21) and the outer ring nozzle (22), and will be ejected from the outer ring nozzle (22a) after speeding up. ) ejected. Gasification agent and natural gas are vigorously mixed at the nozzle, and at the same time, partial oxidation reaction is carried out at high temperature, that is, gasification reaction.

The main function of the internal distributor (17) is to introduce part of the natural gas in the outer channel of the burner into the central nozzle of the burner to form a situation where gasification agent is sandwiched between two streams of natural gas, thereby strengthening mixing and increasing the conversion rate of natural gas.

The inner contraction half-angle α of the center nozzle is 10°-45°, and its lateral inclination β is 30°-80°; the inner contraction half-angle γ of the inner annular nozzle is 10°-45°; the outer inclination τ of the inner annular nozzle is 30°～80°; the inner contraction half angle ε of the outer ring nozzle is 10°～45°.

External cooling liquid enters the cooling chamber (23) through the cooling liquid inlet pipe (3), and then is discharged from the cooling liquid outlet pipe (5) through the coiled pipe (4). The cooling of the cooling liquid in the cooling chamber and coil can effectively protect the burner and improve the service life of the burner.

Detailed ways

According to the concept of the present invention and the content shown in the accompanying drawings, the three-nozzle natural gas partial oxidation synthesis gas burner with internal distributors made has the following technical effects after trial use in relevant factories:

When the natural gas composition is CH ₄ 95.15(vol%), C ₂ H ₆ 0.91(vol%), C ₃ H ₈ 0.14(vol%), CO ₂ 3.80(vol%), S 20ppm, 98% oxygen is Gasification agent, gasification result: the main component of the syngas is CO+H ₂ (vol%) 92.85%, which is at least 1 percentage point higher than that of the existing burner, and the residual CH ₄ in the syngas is significantly higher than that of the existing technology decline.

In a word, the design of the burner of the present invention keeps the external dimensions of the existing burner unchanged, which is conducive to the replacement and use of existing plants (without changing the piping structure), and overcomes its shortcomings, that is, the conversion rate of natural gas is improved. and effective gas (CO+H ₂ ) yield, reducing the combustion intensity of the upper part of the gasifier, increasing the safety and service life of the gasifier, thereby significantly promoting the technological progress of existing industrial devices.

Claims (5)

1. One kind have in three spout preparing synthetic gas by natural gas partial oxidation burners of sparger, it is characterized in that: said burner is by center shower nozzle, interior annular space shower nozzle, outer shroud shower nozzle, and the concentric three spout burners that combine of interior sparger, all component of cooling system, wherein

   Said center shower nozzle (20), it and interior sparger (17) are by Joint after the mechanical engagement, and it communicates with burner outer shroud conduit (12) by equally distributed inclined hole (19) on the interior sparger; The interior contraction half-angle α of center shower nozzle (20) is 10 °～45 °, and its outside angle of inclination beta is 30 °～80 °; The center shower nozzle is by the concentricity of interior sparger (17) maintenance with interior annular space shower nozzle (21);

   Annular space shower nozzle (21) in said, it and interior sparger (17) are by Joint after the mechanical engagement, and it communicates with the burner centre pipe by equally distributed axial straight hole (18) on the interior sparger; Be provided with joint flange (10) on the top of centre pipe (11), match affixed by the supravasal joint flange of it and outer shroud (9), be provided with gasification agent inlet pipe (8) on the top of centre pipe, also be provided with joint flange (14) in the top of gasification agent inlet pipe (8), be connected with the vaporized chemical pipeline by it; The interior contraction half-angle γ of interior annular space shower nozzle (21) is 10 °～45 °; The outer side rake angle τ of interior annular space shower nozzle (21) is 30 °～80 °; Interior annular space shower nozzle (21) is by the concentricity of interior sparger (17) maintenance with center shower nozzle (20);

   Said outer shroud shower nozzle, it and outer shroud conduit (12) are by Joint after the mechanical engagement; Be provided with joint flange (9) on the top of outer shroud conduit (12), match affixed by it with joint flange (10) on the centre pipe, be provided with feed(raw material)inlet pipe (7) on the top of outer shroud conduit (12), below at feed(raw material)inlet pipe (7) also is provided with joint flange (6), by the flange Joint on it and the vapourizing furnace shell; The interior contraction half-angle ε of outer shroud shower nozzle is 10 °～45 °;

   Sparger (17) places burner inside in said, play the natural gas distribution effect, it is processed by forging, go up with burner centre pipe (11) by affixed after the mechanical engagement, pass through after the mechanical engagement affixed with center shower nozzle (20) and interior annular space shower nozzle (21) respectively down; Have axial straight hole (18) on the sparger, vaporized chemical is in centre channel (15) is entered by axial straight hole (18) in the annular space shower nozzle (21); Also have inclined hole (19) on the sparger, one natural gas via burner exterior passage way (16) is entered in the center shower nozzle (20) by inclined hole (19); The sparger outside is provided with flange (28), by the concentricity between its maintenance outer shroud shower nozzle (22) and the interior annular space shower nozzle (21);

   Said cooling system (2) is made of cooling room (23) and coiled pipe (4), and cooling fluid enters cooling room (23) by cooling fluid inlet tube (3), is discharged by coolant outlet (5) behind coiled pipe (4) again; Cooling room (23) is arranged at the outside of burner spout end, is made up of outer side (24), transition flange (25) and the formed space of end face (27) of outer shroud shower nozzle respectively; Coiled pipe (4) is arranged on the outside of burner Lower Half; Said cooling fluid is a water, or other safe liquid.
2. 2. burner as claimed in claim 1 is characterized in that: said vaporized chemical is air, oxygen level greater than 21% oxygen-rich air or oxygen level greater than 98% oxygen.
3. 3. as the described burner in one of claim 1 or 2, it is characterized in that: the flow velocity of vaporized chemical at the spout place is 10～300m/s, and the flow velocity of Sweet natural gas at the spout place is 10～300m/s.
4. 4. burner as claimed in claim 1 is characterized in that: the ratio of the carbon in the oxygen in the vaporized chemical and the Sweet natural gas is 0.50～1.60Nm ³/ kg.
5. 5. burner as claimed in claim 1 is characterized in that: the suitable pressure of said burner is 0.5～12.0MPa.

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