CN112503498A - Enhanced heat transfer vertical pipe type water-cooling gas steam generator - Google Patents

Abstract

The invention discloses a heat transfer enhancement vertical pipe type water-cooling gas steam generator, which comprises an upper header and a lower header, wherein the upper header is provided with a plurality of vertical pipes; a tube array type membrane water-cooling wall is arranged between the upper header and the lower header, a gas inlet and a flue gas outlet are arranged on the tube array type membrane water-cooling wall, the gas inlet is connected with a gas inlet bin, a water-cooling plane burner is arranged in the gas inlet bin, the water-cooling plane burner comprises a water-cooling fire exhaust tube bundle which forms a combustion furnace chamber by being surrounded with the tube array type membrane water-cooling wall, a convection-enhanced heat exchange tube bundle furnace is arranged in the combustion furnace chamber, a heat exchange chamber is formed by the space occupied by the convection-enhanced heat exchange tube bundle, and a combustion chamber is formed by the space between the convection-enhanced heat; the smoke outlet is connected with a tail normal pressure energy saver which is connected with a smoke collection box; the water inlet of the lower header is connected with the water outlet of the tail normal-pressure energy saver through a pipeline and a water pump. The invention has high heat exchange efficiency, low combustion temperature and smoke exhaust temperature, low cost and low nitrogen emission and long service life.

Description

Enhanced heat transfer vertical pipe type water-cooling gas steam generator

Technical Field

The invention relates to a steam generator, in particular to a heat transfer enhancement vertical pipe type water-cooling gas steam generator.

Background

At present, the gas steam generators on the market all adopt a mode of separating a burner from a body, the body is produced by a manufacturer, and the burner is purchased from the outside. The main body structure of the steam generator generally adopts the structural form of a coil pipe, a coiled pipe or a vertical smoke pipe, and the principle is that flame sprayed by a gun type burner or a surface burner or a post-premixing burner heats the coil pipe, the coiled pipe or the smoke pipe of the boiler so as to enable water in contact with the coil pipe, the coiled pipe or the smoke pipe to form steam; the water in the coil pipe or the coiled pipe continuously flows from the lower low-temperature area to the upper high-temperature area, and finally forms steam to be sprayed out. The heating mode enables water in the coil pipe or the coiled pipe to be changed into steam at the tail end of the coil pipe or the coiled pipe, so that the pipe is dry-burned, easy to deform, burn out and scale; the smoke tube type is difficult to achieve the required output without dry burning in a limited volume.

In addition, when the natural gas is combusted, nitrogen in the air reacts with oxygen at high temperature to generate a large amount of nitrogen oxides, when the temperature is lower than 1050 ℃, the generation amount of the nitrogen oxides is extremely small, and when the temperature is higher than 1200 ℃, the generation amount is gradually increased along with the increase of the temperature, and the higher the combustion temperature is, the generation speed of the nitrogen oxides is increased in geometric multiple. Various steam generators on the market at present adopt a gun type diffusion burner (non-low-nitrogen combustion) or an FPB type full-premix metal surface burner to increase the combustion surface to realize low-nitrogen emission, but the FGR nitrogen reduction mode has the defects of high price, reduction of the energy efficiency of a boiler by about 3-5%, and the like, which cannot be overcome; the FPB surface metal burner has the defects of easy blockage, low combustion efficiency, burning out, tempering and the like due to the adoption of a metal mesh combustion surface on the surface, so that the FPB surface metal burner is fouled by people. Meanwhile, water in the boiler can be changed into steam at the tail end of the coil pipe or the coiled pipe, the pipe is dried, and the dried burning temperature is high, so that the water is easy to deform, burn out and scale.

Disclosure of Invention

The invention aims to solve the technical problems of the gas steam generator in the prior art, and provides the enhanced heat transfer vertical pipe type water-cooling gas steam generator which has high heat exchange efficiency, low combustion temperature and smoke discharge temperature, low cost and low nitrogen emission, no dry combustion and long service life.

In order to achieve the purpose, the invention adopts the following technical scheme: a vertical tube type water-cooling gas steam generator with enhanced heat transfer comprises an upper header and a lower header; the top of the upper header is provided with a main steam valve pipe; a tube array type membrane water-cooling wall is arranged between the upper collecting box and the lower collecting box, the upper end and the lower end of the tube array type membrane water-cooling wall are respectively communicated with the upper collecting box and the lower collecting box, the tube array type membrane water-cooling wall is provided with a gas inlet and a flue gas outlet which are opposite, the gas inlet is connected with a gas inlet bin, the gas inlet bin is connected with a premixing fan, a water-cooling plane burner is arranged in the gas inlet bin, the water-cooling plane burner comprises a water-cooling fire exhaust tube bundle and an igniter, and a gas distributing chamber is formed in the space between the water-cooling fire exhaust tube bundle and the gas; the water-cooled fire grate tube bundle and the tube array type membrane water-cooled wall surround to form a combustion furnace chamber, an enhanced convection heat exchange tube bundle is arranged in the combustion furnace chamber, and the upper end and the lower end of the enhanced convection heat exchange tube bundle are respectively communicated with an upper header and a lower header; the space occupied by the enhanced convection heat exchange tube bundle in the combustion furnace cavity forms a heat exchange chamber, and the space between the enhanced convection heat exchange tube bundle furnace and the water-cooling fire grate tube bundle in the combustion furnace cavity forms a combustion chamber; the igniter is arranged on the air inlet bin on one side in the combustion chamber; the smoke outlet is connected with a tail normal pressure energy saver, the tail normal pressure energy saver is connected with a smoke collection box, and a chimney is arranged on the smoke collection box; the water inlet of the lower header is connected with the water outlet of the tail normal-pressure energy saver through a pipeline and a water pump; a liquid level meter pipe is connected between the lower header and the upper header, and a liquid level meter is connected to the liquid level meter pipe. The structure of the steam generator is optimized and improved, the whole material of the steam generator can be stainless steel or carbon steel, and the low-cost water-cooling planar burner is adopted for low-temperature water-cooling combustion, so that the combustion temperature is reduced, and the generation of oxynitride is greatly reduced; the heat exchange is carried out by adopting the enhanced convection heat exchange tube bundle, so that the heat exchange effect is favorably improved, the heat exchange efficiency can be improved by about 30 percent, and the whole material consumption and the water volume of the steam generator are favorably reduced (the temperature is controlled below 30 liters and the water volume is not dried); the fan is arranged in a side spraying mode, and the side spraying mode enables the premixing fan to prevent flue gas from flowing back to the premixing fan to condense water to cause corrosion and dampness of the fan after the premixing fan is stopped; the shell and tube membrane water-cooling wall surrounds the combustion chamber and the heat exchange chamber to form a closed combustion furnace chamber, the shell and tube membrane water-cooling wall increases the heat exchange area, improves the heat efficiency and can reduce the surface temperature of the generator, and a heat insulation layer or a heat preservation layer can be attached to the outer side surface of the shell and tube membrane water-cooling wall; there is the water level electrode in the level gauge, and the water level electrode is opened stopping of water level signal transmission to water level controller in order to control the water pump, carries out the moisturizing with the water pump income collection box down to make the water level of guaranteeing in the intensive convection heat exchange tube bank remain throughout at certain within range, avoid intensive convection heat exchange tube bank dry combustion method and scale deposit, increase of service life, through the water level electrode, the water level controller control water pump open for the conventional means in this field, the event does not have specific details.

Preferably, the water-cooling fire grate tube bundle is composed of a plurality of vertically parallel finned tubes, each finned tube comprises a water-cooling tube and fins, and the fins are fixed on the outer circumferential surface of the water-cooling tube and are arranged at intervals along the axial direction of the water-cooling tube.

Preferably, the water-cooling planar burner further comprises a gas distribution hole plate, the gas distribution hole plate is fixed on the outer side of the water-cooling fire grate tube bundle, two chamfers are arranged on the side edge, close to one side of the gas distribution chamber, of the fin, a V-shaped guide plate is arranged between the adjacent water-cooling tubes, the inclined surface of the V-shaped guide plate is fixedly connected with the chamfers on the fins on the two adjacent sides of the V-shaped guide plate respectively, a gap is arranged between the adjacent V-shaped guide plates, the gap forms an air inlet channel, and a gas distribution hole communicated with the. The V-shaped guide plate can increase the length of the premixed gas water-cooling channel, and plays a role in preventing backfire; the gas is burnt on the finned tubes, so that the burning temperature can be reduced, and ultralow nitrogen emission is realized.

Preferably, the top of the upper header is also provided with a pressure gauge pipe and a safety valve pipe.

Preferably, the intensified convection heat exchange tube bundle is composed of at least one of a plurality of rows of vertically distributed twisted tubes, finned tubes and light tubes.

Preferably, the tube type membrane water-cooling wall comprises water-cooling wall tubes and connecting fins, and the water-cooling wall tubes are welded into an integral structure through the connecting fins.

Preferably, the tail normal-pressure energy saver comprises a shell and a cold water pipe bundle arranged in the shell, the cold water pipe bundle is composed of a plurality of rows of transversely arranged finned tubes, a water inlet chamber and a water outlet chamber are respectively arranged on two sides of the shell, two ends of each finned tube are respectively communicated with the water inlet chamber and the water outlet chamber, and a water inlet of the lower header is connected with a water outlet on the water outlet chamber through a pipeline and a water pump. The cold water tube bundles are horizontally distributed, the design can reduce the smoke resistance, and simultaneously, the condensed water on the fins can naturally drip or be blown off by smoke, so that dust is not easy to accumulate and block (self-cleaning effect).

Preferably, the level gauge pipe and the level gauge are located outside the furnace body. The liquid level meter pipe and the liquid level meter are positioned outside the furnace body and are not heated, so that the accuracy of the water level is ensured.

Preferably, the smoke collection box is in a conical square bucket shape, and the chimney is vertically arranged on the smoke collection box.

Preferably, the lower header is connected with a sewage draining pipe.

Therefore, the invention has the following beneficial effects:

(1) the combustion and exhaust gas temperature is low, and the thermal efficiency can reach more than 105 percent;

(2) by adopting the reinforced heat transfer pipe, the heat exchange efficiency can be improved by about 30 percent, the whole material consumption of the steam generator is reduced, and the whole volume is reduced;

(3) the fan is arranged in a side spraying mode, and the side spraying mode enables the premixing fan to prevent flue gas from flowing back to the premixing fan to condense water to cause corrosion and dampness of the fan after the premixing fan is stopped;

(4) the shell and tube membrane water-cooled wall surrounds the combustion chamber and the heat exchange chamber to form a closed combustion furnace chamber, and not only can the heat exchange area be increased, but also the heat efficiency is improved, and the surface temperature of the furnace body can be reduced;

(5) the water-cooling planar burner is low in cost, can be directly and independently assembled and integrally installed, does not need to buy a burner, can realize low-temperature water-cooling combustion of fuel gas while reducing the production cost, reduces the combustion temperature, can greatly reduce the generation of oxynitride, and is more environment-friendly in emission.

Drawings

FIG. 1 is a front half-sectional view of the present invention.

Fig. 2 is a top half sectional view of the present invention.

Fig. 3 is an enlarged view of a in fig. 2.

In the figure: the device comprises an upper header 1, a lower header 2, a main steam valve pipe 3, a flue gas outlet 4, an air inlet bin 5, an igniter 6, an air distribution chamber 7, a heat exchange chamber 8, a combustion chamber 9, a smoke collection box 10, a chimney 11, a pipeline 12, a water pump 13, a liquid level meter pipe 14, a liquid level meter 15, a water cooling pipe 16, fins 17, an air distribution pore plate 18, a V-shaped guide plate 19, an air inlet channel 20, an air distribution hole 21, a pressure gauge pipe 22, a safety valve pipe 23, a water cooling wall pipe 24, a connecting fin 25, a cold water pipe bundle 26, an air inlet chamber 27, an water outlet chamber 28, a blow-off pipe 29, an intensified convection heat exchange pipe bundle 30, a premixing fan 31 and a shell 32.

Detailed Description

The invention is further described with reference to the following figures and detailed description.

As shown in fig. 1 and 2, the enhanced heat transfer vertical pipe type water-cooled gas steam generator includes an upper header 1 and a lower header 2, both of which are circular; the top of the upper header is connected with a main steam valve pipe 3, a pressure gauge pipe 22 and a safety valve pipe 23, and the lower header is connected with a drain pipe 29; a tube array type membrane water-cooling wall is arranged between the upper header and the lower header, the tube array type membrane water-cooling wall comprises water-cooling wall tubes 24 and connecting fins 25, the water-cooling wall tubes are welded into an integral structure through the connecting fins, the upper and lower ends of the water-cooling wall tubes in the tube array type membrane water-cooling wall are respectively communicated with the upper header and the lower header, the tube array type membrane water-cooling wall is provided with a gas inlet and a flue gas outlet 4 which are opposite, the gas inlet is connected with a gas inlet bin 5, the gas inlet bin is connected with a premixing fan 31, a water-cooling plane burner is arranged in the gas inlet bin, the water-cooling plane burner comprises a water-cooling fire exhaust tube bundle, an igniter 6 and a gas distribution pore plate 18, the water-cooling fire exhaust tube bundle is composed of a plurality of vertical parallel finned tubes, the finned tubes comprise water-cooling tubes 16 and fins 17, the fins are fixed on the outer circumferential, two chamfers are arranged on the side edges of the fins close to one side of the gas distribution chamber, a V-shaped guide plate 19 is arranged between the adjacent water-cooled tubes, the inclined planes of the V-shaped guide plates are respectively and fixedly connected with the chamfers on the fins on the two adjacent sides, a gap is arranged between the adjacent V-shaped guide plates, the gap forms a gas inlet channel 20, and a gas distribution hole 21 communicated with the gas inlet channel is arranged on the gas distribution hole plate; a gas distribution chamber 7 is formed in the space between the water-cooling fire exhaust pipe bundle and the gas inlet bin; the water-cooled fire bank tube bundle and the tube array type membrane type water-cooled wall are enclosed to form a combustion furnace chamber, an enhanced convection heat exchange tube bundle 30 is arranged in the combustion furnace chamber, the enhanced convection heat exchange tube bundle is composed of three rows of light tubes and two rows of finned tubes, the light tubes are positioned on the front side of the finned tubes, and the light tubes are vertically distributed; the upper and lower ends of the light tubes and the finned tubes in the reinforced convection heat exchange tube bundles are respectively communicated with an upper header and a lower header; the space occupied by the enhanced convection heat exchange tube bundle in the combustion furnace cavity forms a heat exchange chamber 8, the space between the enhanced convection heat exchange tube bundle furnace and the water-cooling fire exhaust tube bundle in the combustion furnace cavity forms a combustion chamber 9, and an igniter is arranged on an air inlet bin at one side in the combustion chamber; the smoke outlet is connected with a tail normal-pressure energy saver, the tail normal-pressure energy saver comprises a shell 32 and a cold water pipe bundle 26 arranged in the shell, the cold water pipe bundle is composed of a plurality of rows of transversely arranged finned tubes, a water inlet chamber 27 and a water outlet chamber 28 are respectively arranged on two sides of the shell, two ends of each finned tube are respectively communicated with the water inlet chamber and the water outlet chamber, a water inlet of a lower header is connected with a water outlet on the water outlet chamber of the tail normal-pressure energy saver through a pipeline 12 and a water pump 13, the shell of the tail normal-pressure energy saver is connected with a smoke collection box 10, the smoke collection box is in a conical square bucket shape, and; a liquid level meter pipe 14 is connected between the lower header and the upper header, a liquid level meter 15 is connected on the liquid level meter pipe, and the liquid level meter pipe and the liquid level meter are positioned outside the furnace body.

The operation process of the invention is as follows: the premixing fan mixes gas and air and then sends the mixed gas and air into the air distribution chamber, the mixed gas and air are redistributed by the air distribution chamber and then enter the combustion chamber, the mixed gas is combusted in the combustion chamber under the action of the ignition device, high-temperature flue gas generated by combustion exchanges heat with the enhanced convection heat exchange tube bundle in the heat exchange chamber, water in the enhanced convection heat exchange tube bundle is heated and changed into steam which rises to the header, and the steam is discharged from the main steam valve pipe; the high-temperature flue gas after heat exchange enters the tail energy saver to exchange heat with a cold water pipe bundle in the tail energy saver, the waste heat is utilized to preheat inlet water, and meanwhile, the temperature of the flue gas is further reduced; a water level electrode is arranged in the liquid level meter, transmits a water level signal to the water level controller to control the start and stop of the water pump, and pumps the water in the water outlet chamber into the lower header to replenish water, so that the water level in the enhanced convection heat exchange tube bundle is always kept in a certain range, and the enhanced convection heat exchange tube bundle is prevented from being burnt and scaled; the flue gas cooled by the cold water pipe bundle finally enters a flue gas collection box and is discharged from a chimney.

The above-described embodiments are only preferred embodiments of the present invention, and are not intended to limit the present invention in any way, and other variations and modifications may be made without departing from the spirit of the invention as set forth in the claims.

Claims (10)

1. An enhanced heat transfer riser type water-cooled gas steam generator, characterized in that it comprises an upper header (1) and a lower header (2); the top of the upper header is provided with a main steam valve pipe (3) There is a tubular membrane type water-cooling wall between the upper header and the lower header, and the upper and lower ends of the tubular membrane water-cooling wall are respectively communicated with the upper header and the lower header. The membrane-type water-cooling wall is provided with opposite gas inlets and flue gas outlets (4), the gas inlets are connected with an air intake silo (5), the air intake silo is connected with a premix fan (31), and the air intake silo is connected with A water-cooled plane burner is provided, the water-cooled plane burner includes a water-cooled fire exhaust tube bundle and an igniter (6), and the space between the water-cooled fire exhaust tube bundle and the air intake bin forms an air distribution chamber (7); The tube bundle and the tube-and-tube-type membrane water-cooling wall are enclosed to form a combustion furnace cavity. The combustion furnace cavity is provided with an enhanced convection heat exchange tube bundle (30), and the upper and lower ends of the enhanced convection heat exchange tube bundle are respectively connected to the upper header. The space occupied by the enhanced convection heat exchange tube bundle in the combustion furnace cavity forms a heat exchange chamber (8), and the space between the enhanced convection heat exchange tube bundle and the water-cooled fire exhaust tube bundle in the combustion furnace cavity forms the combustion chamber (9); the igniter is arranged on the air intake silo on one side of the combustion chamber; the exhaust gas outlet is connected with a tail atmospheric pressure economizer, and the tail atmospheric pressure economizer is connected with a smoke collecting box (10), so The smoke collecting box is provided with a chimney (11); the water inlet of the lower header and the water outlet of the atmospheric pressure economizer at the tail are connected by a pipeline (12) and a water pump (13); the connection between the lower header and the upper header A liquid level gauge tube (14) is connected, and a liquid level gauge (15) is connected to the liquid level gauge tube. 2 . The enhanced heat transfer riser type water-cooled gas-fired steam generator according to claim 1 , wherein the water-cooled fire tube bundle is composed of a plurality of vertically juxtaposed finned tubes, and the finned tubes include: 3 . A water-cooling tube (16) and fins (17), the fins are fixed on the outer circumferential surface of the water-cooling tube and are arranged at intervals along the axial direction of the water-cooling tube. 3. An enhanced heat transfer riser type water-cooled gas steam generator according to claim 2, characterized in that the water-cooled plane burner further comprises an air distribution orifice plate (18), and the air distribution orifice plate is fixed on the water-cooled orifice plate. On the outside of the fire exhaust tube bundle, two chamfers are provided on the side of the fin near the gas distribution chamber, and a V-shaped baffle (19) is arranged between adjacent water-cooled tubes. The V-shaped baffle The inclined surfaces of the fins are respectively fixedly connected with the chamfers on the adjacent two sides of the fins, a gap is formed between the adjacent V-shaped guide plates, and the gap forms an air intake channel (20), and the air distribution orifice plate is provided with a connection to the air intake channel open air holes (21). 4 . The enhanced heat transfer riser type water-cooled gas steam generator according to claim 1 , wherein a pressure gauge pipe ( 22 ) and a safety valve pipe ( 23 ) are further provided on the top of the upper header. 5 . 5 . The enhanced heat transfer riser type water-cooled gas steam generator according to claim 1 , wherein the enhanced convection heat exchange tube bundle is composed of several rows of vertically distributed twisted tubes, finned tubes, optical At least one of the tubes is constructed. 6. An enhanced heat transfer riser type water-cooled gas steam generator according to claim 1, characterized in that, the tubular membrane type water-cooled wall comprises a water-cooled wall tube (24) and connecting fins (25) , and the water-cooled wall tubes are welded into an integrated structure by connecting fins. 7. An enhanced heat transfer riser type water-cooled gas steam generator according to claim 1, characterized in that the tail atmospheric pressure economizer comprises a casing (32) and a cold water tube bundle (26) arranged in the casing ), the cold water tube bundle is composed of multiple rows of finned tubes arranged horizontally, a water inlet chamber (27) and a water outlet chamber (28) are respectively provided on both sides of the casing, and the two ends of the finned tubes are respectively connected to the inlet and outlet chambers (28). The water chamber and the water outlet chamber are connected, and the water inlet of the lower header and the water outlet on the water outlet chamber are connected through pipelines and a water pump. 8 . The enhanced heat transfer riser type water-cooled gas steam generator according to claim 1 , wherein the liquid level gauge tube and the liquid level gauge are located outside the furnace. 9 . 9 . The enhanced heat transfer riser type water-cooled gas steam generator according to claim 1 , wherein the smoke collecting box is in the shape of a conical square, and the chimney is vertically arranged on the smoke collecting box. 10 . . 10 . The enhanced heat transfer riser type water-cooled gas steam generator according to claim 1 , wherein a sewage pipe ( 29 ) is connected to the lower header. 11 .

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