CN207537404U - A kind of dry coal powder pressure gasifying stove of band screen formula radiation waste pot - Google Patents

Abstract

The utility model relates to a dry coal powder pressurized gasification furnace with a screen-type radiant waste pot. Air-conditioning interface, etc.; dry coal powder and oxidizing medium enter the first-stage reaction zone of the gasifier through the first-stage pulverized coal burner to react to generate high-temperature synthesis gas, and the high-temperature synthesis gas enters the second-stage reaction zone and the dry coal powder and weak oxidizing medium input in the second stage High-temperature cracking and gasification reactions occur to further generate synthesis gas and reduce the temperature of the synthesis gas; the high-temperature synthesis gas exchanges heat with the second-stage water-cooled wall and the screen-type radiant waste boiler to generate steam, further reducing the temperature of the high-temperature synthesis gas and reducing the subsequent synthesis Dimensions of equipment such as gas cooler, dust collector, scrubber, etc.; set the inlet of chilled gas behind the screen-type radiant waste boiler, and feed the chilled gas into the furnace to reduce the temperature of the syngas at the outlet of the gasifier to 300 ° C ~ 800 ° C; During the implementation process, the input of pulverized coal and quenching gas in the second stage is optional.

Description

A dry coal powder pressurized gasifier with screen-type radiant waste pot

technical field

The utility model belongs to the technical field of energy and chemical industry, and in particular relates to a pressurized gasification furnace for dry coal powder with a screen-type radiant waste pot.

Background technique

Total heat recovery dry pulverized coal pressurized gasification technology has good coal type adaptability, high cold gas efficiency, high gasification thermal efficiency, low waste water volume, and excellent environmental protection performance. It is the most important direction for the development of modern coal gasification technology. Among the currently industrially applied dry coal powder pressurized gasification technologies with full heat recovery, such as SHELL coal gasification technology, Prenflo coal gasification technology, Huaneng coal gasification technology, etc., SHELL coal gasification technology and Prenflo coal gasification technology adopt one-stage gasification, high temperature The syngas completely depends on the chilled gas circulation to cool down. The chilled gas circulation rate is usually 100% to 200%. The power consumption of the device is high, the syngas cooler, dust collector, scrubber and other equipment are huge, and the operation cost and equipment investment are high. The Huaneng Furnace adopts two-stage gasification, using the heat of chemical reaction to quench the high-temperature syngas, but it still needs to quench the low-temperature syngas with about 50% of the output of the circulating syngas, and for the coal with poor reactivity, the chemical quenching The effect will be weakened. This technology reduces the amount of chilled air and the size of the equipment, but the adaptability to coal types is still limited, and the equipment cost and operating power consumption are still high.

The temperature of the high-temperature syngas is about 1500°C, and the radiation heat transfer is strong. The temperature gradient between the surface of the tube-tube-panel heat exchange surface and the high-temperature syngas and the liquid slag carried by it is large, and the high-temperature ash slag contacts the surface of the heat exchange surface will be rapidly cooled and solidified, and it is not easy to cause ash sticking and slagging. Based on this principle, the utility model proposes a new dry coal powder pressurized gasification furnace with screen-type radiant waste boiler, further expands the coal type adaptability of dry coal powder pressurized gasification technology, improves heat exchange efficiency, reduces or The amount of chilled air circulation is canceled to further reduce the size of the equipment.

Contents of the invention

In order to overcome the above-mentioned problems in the prior art, the purpose of this utility model is to provide a dry coal powder pressurized gasifier with a screen-type radiant waste boiler, which can realize chemical quenching of high-temperature syngas and heat exchange of the screen-type radiant waste boiler The flexible adjustment of various high-temperature syngas cooling means in the design and operation of the gasifier, such as chilled gas cooling, etc., improves the coal type adaptability and operational reliability of the gasifier at the same time.

In order to achieve the above object, the utility model is realized through the following technical solutions:

A dry pulverized coal pressurized gasifier with a screen-type radiant waste boiler, comprising a gasifier shell 1, the upper side of the outer wall of the gasifier shell 1 is provided with a synthesis gas outlet 16, an upper header interface 3 and The chilled air inlet 4 is provided with a boiler water inlet 9 and a slag pool water inlet 12 at the bottom, and a slag water outlet 10 is provided at the bottom; the gasifier shell 1 is provided with an upper header 2, a screen Type radiant waste pot 15, water wall 5 and lower header 8, the middle part of water wall 5 has a water wall shrinkage 14, the bottom is a liquid slag discharge port 13, and the water wall shrinkage 14 and liquid slag discharge port 13 drain the inside of the water wall 5 The cavity is divided into a first-stage reaction zone I and a second-stage reaction zone II from bottom to top; multiple first-stage burners 7 and multiple second-stage burners 6 are respectively arranged in the middle of the first-stage reaction zone I and the middle of the second-stage reaction zone II along the horizontal direction .

The gasifier adopts dry powder pressurized gasification, the gasification pressure is 0.5-6.5MPa, and the reaction temperature is 1200°C-1800°C; the gasifier adopts a liquid slag discharge method; the gasifier shell 1 is used as a pressure vessel Under the gasification pressure, the furnace adopts a water-cooled wall 5 structure to prevent the gasification furnace shell 1 from overheating.

The water-cooled wall 5 is formed by connecting water-cooled pipes 17 and fins 18. A screen-type radiant waste pot 15 is arranged on the upper part of the second-stage reaction zone II. Boiler water enters the lower header 8 through the boiler water inlet 9 for distribution, so that the water-cooled wall 5 The flow rate of each water-cooled tube of the screen-type radiant waste boiler 15 meets the requirements of heat load, and the boiler water or water-steam mixture after heat exchange converges in the upper header 2 and is sent out of the gasifier through the upper header interface 3 .

The screen-type radiation waste pot 15 is formed by connecting water-cooling pipes 17 and fins 18, the elbow of the water-cooling pipe 17 is a right-angle elbow 20, and the upper part of the screen-type radiation waste pot 15 is provided with a quenching air inlet 4, and the cooled The synthesis gas is sent out of the gasifier through the outlet 16 of the synthesis gas, and a slag pool 11 is arranged at the bottom of the gasifier, and the water in the slag pool is fed in through the water inlet 12 of the slag pool, and the solidified slag particles are discharged from the solid slag outlet 10 .

The first-stage reaction zone I is covered with refractory materials, and the second-stage reaction zone II is not covered with refractory materials; the number of burners 7 in the first stage is 2 to 8; when there are two burners, they are horizontally opposed, and when there are more than three , arranged according to a tangential circle, the angle α between the centerline of the burner 7 and the diameter of the gasifier is 0-9°.

The gasification furnace adopts staged gasification, and the first-stage burner 7 feeds include gasification raw materials and oxidants; the gasification raw materials are powders made from coal, coke, semi-coke, petroleum coke and biomass, and the oxidants are pure oxygen, Oxygen-enriched or pure oxygen, a mixture of oxygen-enriched and water vapor or carbon dioxide; the feed to the second-stage burner 6 mainly includes gasification raw materials and oxidants; the gasification raw materials are mainly coal and biomass, and the oxidants are mainly water vapor or carbon dioxide; The feeding amount of the second stage accounts for 0-10% of the total feeding amount, and the feeding amount of the second stage gasification is 0 when the reaction activity of the raw material of the second stage gasification is low.

The screen-type radiant waste pot 15 adopts a plurality of heat exchange screens 19, and each heat exchange screen 19 is connected with the water-cooled wall 5 by fins 18, and the heat exchange screens 19 are radially and evenly distributed to the middle of the furnace, and the heat exchange The number of screens 19 is determined based on the heat exchange rate of the high-temperature syngas cooling and the allowed arrangement space in the gasifier.

The gasification furnace is equipped with quenching gas to ensure that the temperature of the synthesis gas at the outlet of the gasifier can be reduced to below 800°C; the circulation rate of the quenching gas is 0% to 60% of the gas production of the gasification furnace. When chemical quenching and screen radiation When the waste boiler is sufficient to reduce the temperature of the syngas to below 800°C, the amount of chilled gas is 0.

The high-temperature syngas cooling of the gasification furnace adopts two-stage feeding chemical quenching, screen-type radiant waste boiler 15 heat exchange and cooling, and quenching gas mixing and cooling. When the gasification raw material put into the gasifier is reactive When the raw material is high, choose chemical chilling, reduce or not put in chilling air; when the gasification raw material is a low-activity raw material, choose to put in chilling air, reduce or not set the second-stage feeding; the replacement of the screen type radiation waste pot 15 The heat area is arranged in combination with the space allowed to be utilized in the upper section of the gasifier.

In the working method of the dry pulverized coal pressurized gasifier with a screen-type radiant waste boiler, the gasification raw material enters the first-stage reaction zone 1 horizontally through a plurality of first-stage burners 7 to generate high-temperature syngas; the high-temperature syngas Enter the second-stage reaction zone II through the water-cooled wall constriction 14, and the gasification raw material entering the second-stage burner 6 reacts with the high-temperature synthesis gas to absorb heat, and realizes chemical quenching to reduce the temperature of the high-temperature synthesis gas; the synthesis gas after the second-stage reaction Through the heat exchange of the screen-type radiant waste pot 15, the temperature of the synthesis gas is continuously lowered, and steam is generated again; The synthetic gas is sent out of the gasifier through the outlet 16; the high-temperature liquid slag produced by gasification enters the slag pool 11 through the liquid slag discharge port 13 and enters the slag pool 11, which is quenched by water to form glassy particles, and is discharged out of the gasifier through the solid slag discharge port 10.

The utility model adopts dry coal powder pressurized gasification, and a screen-type radiant waste pot is arranged on the upper part of the second-stage reaction zone, which can not only reduce the temperature of the synthesis gas, but also produce steam by-product, avoid ash slagging in the high-temperature heat exchange area, and also reduce the The size of subsequent syngas coolers, dust collectors, scrubbers and other equipment has been specified, and various high-temperature syngas cooling methods such as chemical quenching of high-temperature syngas, heat exchange of screen-type radiant waste boilers, and quenching gas cooling have been realized in the design and operation of gasifiers. The flexible adjustment in the gasifier also improves the coal type adaptability and operation reliability of the gasifier.

Description of drawings

Fig. 1 is a schematic structural diagram of a gasifier of the present invention.

Fig. 2 is a schematic diagram of the arrangement of a burner of the utility model.

Figure 3 is a top view of the water wall of the screen-type radiant waste pot section and the radiant waste pot.

Fig. 4 is a schematic diagram of the structure of the screen-type radiant waste boiler heat exchange screen.

Fig. 5 is a schematic diagram of a right-angle elbow of a screen-type radiant waste pot.

1. Gasifier shell; 2. Upper header; 3. Upper header interface; 4. Chiller air inlet; 5. Water wall; 6. Second-stage burner; 7. First-stage burner; 8. Lower header; 9. Boiler water inlet; 10. Solid slag outlet; 11. Slag pool; 12. Slag pool water inlet; 13. Liquid slag outlet; ; 17, water cooling tube; 18, fins; 19, heat exchange screen; 20, right angle elbow. I. One-stage reaction zone; II, Two-stage reaction zone.

Detailed ways

Below in conjunction with accompanying drawing, the utility model is further described. Those skilled in the art understand that the following content does not limit the protection scope of the present utility model. Any improvements and changes made on the basis of the utility model are within the protection scope of the utility model.

As shown in Figure 1, the utility model is a dry coal powder pressurized gasification furnace with a screen-type radiant waste boiler, which includes a syngas outlet 16 on the upper side of the outer wall, an upper header outlet pipe 3, and a quenching gas The inlet 4 and the lower bottom are provided with a boiler water inlet 9 , a slag pool water inlet 12 , and a slag water outlet 10 for the gasifier shell 1 . The gasification furnace shell 1 is provided with a water wall 5 with an upper header 2, a screen-type radiant waste pot 15, a water wall shrinkage 14, a liquid slag outlet 13, and a lower header 8 from top to bottom. The water wall shrinkage 14 and the liquid slag outlet 13 divide the inner cavity of the water wall 5 from bottom to top into a first-stage reaction zone I and a second-stage reaction zone II. A plurality of first-stage burners 7 and a plurality of second-stage burners 6 are respectively arranged in the middle of the first-stage reaction zone I and the middle of the second-stage reaction zone II along the horizontal direction.

The working method of the dry pulverized coal pressurized gasifier is as follows: the gasification raw material enters the first-stage reaction zone 1 horizontally through a plurality of first-stage burners 7 to generate high-temperature synthesis gas; the high-temperature synthesis gas enters through the water-cooled wall constriction 14 In the second-stage reaction zone II, the gasification raw material entering the second-stage burner 6 reacts with the high-temperature synthesis gas to absorb heat and realize chemical quenching to reduce the temperature of the high-temperature synthesis gas; the synthesis gas after the second-stage reaction passes through the screen-type radiation waste pot 15 heat exchange, continue to reduce the synthesis gas temperature, and generate high-temperature steam; the synthesis gas cooled by the screen type radiant waste pot 15 is mixed with the chilled air fed into the chilled air inlet 4 to cool down, and the cooled syngas is sent out through the synthesis gas outlet 16 gasifier. The high-temperature liquid slag produced by gasification enters the slag pool 11 through the liquid slag outlet 13 and is quenched by water to form glass particles, and is discharged out of the gasifier through the solid slag inspection port 10 .

The high-temperature syngas is cooled by various means such as chemical chilling, screen-type radiative waste boiler heat exchange, and chilled air. When the gasification raw material put into the gasifier is a gasification raw material with high reactivity, Prefer chemical chilling, reduce or cancel the amount of chilling air input, when the gasification raw material is a raw material with low reactivity, preferably put in chilling air, reduce or cancel the second-stage input of gasification raw material, heat exchange of the screen type radiant waste pot 15 The area is combined with the space arrangement allowed by the upper section of the gasifier.

The gasification furnace adopts dry powder pressurized gasification, the gasification pressure is 0.5-6.5MPa, the reaction temperature is 1200°C-1800°C, the gasification furnace adopts the liquid slagging method, and the gasification furnace shell 1 is used as a pressure vessel to withstand the gasification pressure, the furnace adopts a water-cooled wall 5 structure to avoid overheating of the gasifier shell 1.

The water-cooled wall 5 is formed by connecting water-cooled pipes 17 and fins 18. The water-cooled wall 5 forms a first-stage reaction zone I and a second-stage reaction zone II by constructing a liquid slag discharge port 13 and a water-cooled wall shrinkage 14. Refractory material is applied in zone I, and refractory material is not enough in zone II of the second-stage reaction.

The gasification furnace adopts a plurality of first-stage burners 7 arranged horizontally to feed materials, and the first-stage burners 7 are arranged in the middle of the first-stage reaction zone I, and the number of the first-stage burners 7 is usually 2 to 8, which are horizontally opposed or cut. Arranged in a circle (when the number of one-stage burners 7 is more than three), the angle α between the center line of the first-stage burners 7 and the diameter of the gasifier is 0-9° (see Figure 2 for details). The gasification raw material of powder is usually fed by a pressurized lock hopper system or a warehouse pump, and conveyed in dense phase, which requires stable and adjustable feed.

The feed to the first-stage burner 7 includes gasification raw materials and oxidants. The gasification raw material can be powder made of coal, coke, semi-coke, petroleum coke, biomass and other raw materials, and the oxidant can be pure oxygen, oxygen-enriched or a mixture of pure oxygen, oxygen-enriched and water vapor/carbon dioxide.

The second-stage burner 6 is an optimal design, which is mainly used for gasification raw materials with high reactivity, and the feed mainly includes gasification raw materials and oxidants. The gasification raw materials are mainly coal and biomass, etc., and the oxidant is mainly water vapor or carbon dioxide. The feeding amount of the second stage accounts for 0-10% of the total feeding amount, that is, the feeding amount of the second stage gasification is 0 when the reaction activity of the raw material of the second stage gasification is low.

The screen-type radiant waste pot 15 adopts a plurality of heat exchange screens 19, and the heat exchange screens 19 are radially and evenly distributed in the middle of the furnace (as shown in Figure 3 ). Between each heat exchange screen 19 and the water cooling wall 5 are The fins 18 are connected, and the number of heat exchange screens 19 is determined based on the heat transfer capacity of the high-temperature syngas cooling and cooling and the space allowed for arrangement in the gasifier, usually 2 to 15.

The composition of the heat exchange panel 19 is similar to that of the water-cooled wall 5, and is formed by connecting the water-cooled tube 17 and the fin 18 (as shown in Figure 4), and the elbow of the water-cooled tube 17 adopts a 90° right-angle elbow 20 (as shown in FIG. 5).

The upper water of the water-cooled tubes 17 in the water-cooled wall 5 and the heat exchange panel 19 is sent to the lower header 8 through the boiler water inlet 9 for distribution, so that the The flow rate meets the requirements of the heat load, and the boiler water (or water-steam mixture) after heat exchange gathers in the upper header 2 and is sent out from the outlet pipe 3 of the upper header. In the detailed design, a plurality of lower headers 8 and upper headers 2 can be provided according to the size of the annular space between the water wall 5 and the shell 1, hydrodynamic requirements and other factors.

The above-mentioned chilling gas is an optimal design. After the high-temperature syngas is chemically chilled in the second-stage reaction zone II and heat-exchanged by the screen-type radiation waste pot 15, when the temperature of the syngas is still higher than 800°C, it passes through the quenching gas inlet 4 directions. The cold synthesis gas is fed into the furnace and mixed with the high-temperature synthesis gas to exchange heat, reducing the temperature of the synthesis gas to below 800°C. The amount of chilled gas circulation is 0-60% of the gas output of the gasifier, that is, when the chemical chilling and screen radiation waste pot are sufficient to reduce the temperature of the syngas to below 800°C, the chilled gas volume is 0.

The slag pond 11 is provided with a slag pond water inlet 12, and quenching water is sprayed into the slag pond 11 through the slag pond water inlet 12, and the liquid slag from the liquid slag outlet 13 meets the water in the slag pond 11 and is quenched into fine glass particles .

Working principle of the utility model

Carbon-containing gasification raw materials (coal, coke, semi-coke, petroleum coke, biomass, etc.) and oxidizing medium (oxygen, a mixture of oxygen-enriched water vapor or carbon dioxide) undergo gasification reactions in a pressurized state to produce high-temperature syngas and liquid slag. The liquid slag flows into the slag pool and is quenched by water to form glass particles. The high-temperature syngas carrying molten fly ash ascends, and adopts multiple cooling methods to optimize the design. Method 1: Continue to input a small amount of gasification raw materials and water vapor or carbon dioxide, use the sensible heat of high-temperature synthesis gas to perform high-temperature cracking and partial gasification reaction, generate a certain amount of synthesis gas, absorb heat at the same time, and reduce the temperature of synthesis gas (chemical chilling ); Method 2: Set up the screen-type radiant waste pot with tubes, because the radiation heat transfer of high-temperature syngas is strong, the temperature gradient between the surface of the screen-type radiant waste pot with tubes, high-temperature syngas and the liquid slag carried by it is large , the high-temperature ash slag will quickly cool and solidify when it contacts the heat exchange surface, and it is not easy to cause ash sticking and slagging. Method 3: Set up chilled air to assist cooling. When methods 1 and 2 cannot ensure that the temperature of the syngas drops below 800°C , into the furnace into the chilled gas (low temperature synthesis gas), so that the temperature of the synthesis gas down to the temperature of the downstream safe operation. Mode 1 and Mode 3 are optimal designs. When the gasification raw material is a raw material with high reactivity, focus on adopting Mode 1 and Mode 2, and set a small amount or no chilling gas. When the gasification raw material is a raw material with low reactivity, focus on Adopt method 2 and method 3, reduce or not set the second-stage feeding. The use of screen-type radiant waste boiler can further expand the coal type adaptability of dry pulverized coal pressurized gasification technology, improve heat exchange efficiency, reduce or cancel the amount of chilled air circulation, and further reduce the size of equipment.

Claims (6)

1. a kind of dry coal powder pressure gasifying stove of band screen formula radiation waste pot, including the furnace shell 1 that gasifies, it is characterised in that：The gas Change furnace shell (1) outer wall upper side and be provided with syngas outlet (16), upper header interface (3) and sharp cold air inlet (4), lower part Boiler water inlet (9) and slag bath water inlet (12) are provided with, bottom is provided with pulp water outlet (10)；The gasification furnace shell (1) It is inside equipped with sequentially connected upper header (2), screen formula radiation waste pot (15), water-cooling wall (5) and lower collecting box (8), water cooling from top to bottom Water-cooling wall necking (14) is carried in the middle part of wall (5), bottom is liquid slag outlet (13), water-cooling wall necking (14) and liquid slag discharge Water-cooling wall (5) internal cavity is divided into one section of reaction zone (I) and second-stage reaction area (II) by mouth (13) from the bottom to top；Multiple one section of burning Mouth (7) and multiple two sections of burners (6) are arranged in the middle part of one section of reaction zone (I) and second-stage reaction area (II) in the horizontal direction respectively Middle part.

2. a kind of dry coal powder pressure gasifying stove of band screen formula radiation waste pot according to claim 1, it is characterised in that：It is described Water-cooling wall (5) be formed by connecting by water cooling tube (17) and fin (18), second-stage reaction area (II) top sets screen formula radiation waste pot (15)。

3. a kind of dry coal powder pressure gasifying stove of band screen formula radiation waste pot according to claim 1, it is characterised in that：It is described Screen formula radiation waste pot (15) be formed by connecting by water cooling tube (17) and fin (18), the elbow of water cooling tube (17) is elbow bend (20), the setting of screen formula radiation waste pot (15) top swashs cold air inlet (4), and synthesis gas after cooling is sent by syngas outlet (16) Go out gasification furnace, bottom setting slag bath (11) in gasification furnace, slag bath water is sent by slag bath water inlet (12), the solid impurity particle after solidification by Solid-state slag outlet (10) is discharged.

4. a kind of dry coal powder pressure gasifying stove of band screen formula radiation waste pot according to claim 1, it is characterised in that：It is described One section of reaction zone (I) in apply refractory material, second-stage reaction area (II) not apply refractory material；The quantity of one section of burner (7) It is 2~8；When being two, by horizontally-opposed, at extra three, arranged by the circle of contact, one section of burner (7) center line and gasification furnace It is 0~9 ° that diameter, which deviates angle α,.

5. a kind of dry coal powder pressure gasifying stove of band screen formula radiation waste pot according to claim 1, it is characterised in that：It is described Gasification furnace using classification gasification, one section of burner (7) charging includes gasified raw material and oxidant；Gasified raw material for coal, coke, Semicoke, petroleum coke and biomass are powder made of raw material, and oxidant is pure oxygen, oxygen-enriched or pure oxygen, oxygen-enriched and water vapour or two The mixture of carbonoxide；Two sections of burner (6) chargings mainly include gasified raw material and oxidant；Gasified raw material is mainly coal and life Substance, oxidant are mainly water vapour or carbon dioxide；Two sections of inventorys account for total amount of feeding 0~10%, when two sections of gasified raw materials Two sections of inventorys are 0 when reactivity is low.

6. a kind of dry coal powder pressure gasifying stove of band screen formula radiation waste pot according to claim 1, it is characterised in that：It is described Screen formula radiation waste pot (15) shield (19) using multiple heat exchange, by fin (18) between each heat exchange screen (19) and water-cooling wall (5) Connection, heat exchange screen (19) is radially uniformly distributed among burner hearth, and the quantity of heat exchange screen (19) is cooled based on high-temperature synthesis gas Heat exchange amount and gasification furnace in allow arrangement space determine.