CN206944114U - Gas fuel boiler with compound water-cooled furnace - Google Patents

Abstract

Gas fuel boiler with compound water-cooled furnace, including boiler body, boiler body inner right side is burner hearth, some spiral finned tubes are evenly arranged with the inside of the water cooled membrane wall of burner hearth surrounding, water cooled membrane wall is encircled into outer burner hearth, these spiral finned tubes are encircled into internal furnace, water cooled membrane wall and spiral finned tube are in freeze profile into compound water-cooled furnace, every spiral finned tube vertical direction between upper drum and lower drum is arranged, the upper end of all spiral finned tubes is extend into upper drum, and the lower end of all spiral finned tubes is extend into lower drum.The utility model reduces the temperature of burner hearth and the temperature of furnace outlet when not increasing boiler volume or even reducing boiler volume, reduces the growing amount of boiler heating power type nitrogen oxides, facilitates the arrangement of superheater, reduces boiler entirety steel consumption.

Description

Gas fuel boiler with compound water-cooled furnace

Technical field

It the utility model is related to a kind of boiler, more particularly to the gas fuel boiler with compound water-cooled furnace.

Background technology

For a long time, always using coal as main energy sources, coal-burning boiler largely uses in China, forms the dirt of coal smoke type air Dye, the haze weather especially occurred more in recent years, the energy policy and energy resource structure for further promoting China make the transition as early as possible. The coal-fired industry in China and the usage amount of domestic boiler are huge at present, are the important pollution sources of China's haze weather, therefore I The big or middle city of some of state has been formulated in the recent period to be changed to fuel oil industry or life coal-burning boiler or fires the boiler policy of natural gas, So can not only solve the conspicuous contradiction between boiler fired coal and environment, and under the background of transfering natural gas from the west to the east, in policy It is exercisable, the policy of boiler " coal changes oil " or " coal changes gas " can keep continuity at present and in the quite a while.

At present in fuel oil and combustion natural gas boiler, the SZS fuel oils that industrial and boiler for domestic uses fire natural gas boiler number Measure huge, be primarily due to that its is simple in construction, automaticity is high, and the cycle of production and installation is short, especially medium small boiler Strong adaptability, therefore firmly get the favor of user, the occupation rate of in the market is increasing.As country and local government are to burning The boiler limitation scope and tonnage of coal are increasing, and SZS type boilers have welcome the great development phase, and the typical structure of this boiler is main Including two parts, boiler side is the burner hearth of biasing, and burner hearth end arrangement burner, burner hearth is as the sky for providing fuel combustion Between, burner hearth surrounding arrangement water cooled membrane wall heating surface, these heating surfaces play a part of absorbing heat and sealed, due to these heating surfaces It is main to absorb flame radiation heat, therefore referred to as radiation heating-surface；Opposite side arranges superheater and convection bank or only convection current Tube bank, these heating surfaces are used for absorbing flow of flue gas liberated heat, are referred to as convection heating surface, the four of the two parts are thorough Portion is sealed with water cooled membrane wall, can so be used as entirety to be dispatched from the factory after boiler manfacturing unit assembles, to after scene It is easily installed, shortens the set-up time, be user-friendly.During the design and use of this boiler, due to structure and fortune Defeated limitation, the burner hearth of boiler are typically designed smaller, and liberated heat can not be by burner hearth internal-combustion for such fuel The monolayer film type water-cooling wall of surrounding absorbs in time, and the temperature caused inside burner hearth is very high, can reach 1400 °C or so sometimes, So there are two subject matters：One be due to temperature more than 1200 degree, boiler heating power type oxynitrides largely produces, and Current environmental protection policy is runed counter to, and in order to reduce the generation of oxynitrides, burning only reduces the supply of oxygen, made as far as possible It is incomplete into fuel combustion, substantial amounts of CO is generated, not only wastes fuel, and boiler operator is also dangerous；Second, The furnace outlet of boiler and later convection heating surface arrangement are more difficult, are mainly manifested in two aspects：One is gone out due to burner hearth Mouth flue-gas temperature is too high, and superheater can not be arranged at furnace outlet, avoids burning out for superheater, and this and superheater need to arrange Runed counter in the theory of cigarette temperature highest point, and if be arranged in furnace outlet when superheater is installed, can be on superheater two sides Positioning, is easily installed and checks, must take arrange protection superheater i.e. at furnace outlet before superheater one at present Divide convection bank, superheater can only observe the situation towards the superheater of boiler exterior when installing, because another side is to abut stove Thorax membrane wall, have no idea to be positioned and checked；Second, because flue gas temperature of hearth outlet is too high（Some reaches 1400 ° C or so）, in order to reduce the flue-gas temperature of boiler export, it has to arrange convection heating surface more, this and need to design compact The theory that boiler volume is readily transported and installed is runed counter to, and result is that a part of heating surface is moved on to outside boiler, increases boiler section No matter energy heating surface, increase part heating surface, if because the heat-transfer intensity of convection heating surface is more many than radiant heat transfer, same Exhaust gas temperature in the case of, absorb same heat, all big more of the steel consumption of convection heating surface, be unfavorable for the energy-conservation drop of boiler Consumption, in summary 2 points can be seen that.For SZS types oil-burning gas-fired boiler due to structure and the limitation of transport, traditional burner hearth four Week, the individual layer water cooled membrane wall heat absorption capacity of arrangement was limited, caused the temperature in boiler furnace too high and flue gas temperature of hearth outlet It is too high, the too high generation for adding oxynitrides of temperature in burner hearth, although nitrogen can be reduced using the method for low supply oxygen amount The generation of oxygen compound, but it is incomplete to result in fuel combustion, flue gas temperature of hearth outlet is too high to make heating surface arrangement tired Difficulty, the overall steel consumption and installation difficulty of boiler are added, is unfavorable for the energy-saving of boiler.

Utility model content

The utility model is in order to solve weak point of the prior art, there is provided a kind of limited space inside burner hearth It is interior, spiral finned tube is set to reduce burner hearth internal temperature, so as to which that reduces NO_x formation has compound water-cooled furnace Gas fuel boiler.

In order to solve the above technical problems, the utility model adopts the following technical scheme that：Combustion gas with compound water-cooled furnace Oil burning boiler, including boiler body, boiler body inner right side are burner hearth, and boiler body front portion right side opening is installed provided with burner Hole, burner hearth surrounding inwall are provided with water cooled membrane wall, are provided with upper drum and lower drum on the left of boiler body, upper drum and cook Cylinder is connected by convection bank, and burner hearth outlet flue is arranged on the water cooled membrane wall rear portion on the left of burner hearth, in upper drum and lower drum Between and superheater is provided with the burner hearth outlet flue, front portion is provided with boiler nozzle, burner hearth surrounding on the left of boiler body Water cooled membrane wall on the inside of be evenly arranged with some spiral finned tubes, water cooled membrane wall is encircled into outer burner hearth, these spiral fins Piece pipe is encircled into internal furnace, water cooled membrane wall and spiral finned tube in freeze profile into compound water-cooled furnace, every helix fin Pipe vertical direction between upper drum and lower drum arranges that the distance between spiral finned tube and water cooled membrane wall is more than water cooled membrane The water pipe caliber of wall, the upper end of all spiral finned tubes are extend into upper drum, and the lower end of all spiral finned tubes is equal It extend into lower drum, the length that spiral finned tube is extend into upper drum and lower drum is not more than 10mm；When installing boiler, Spiral finned tube assembles in place prior to water cooled membrane wall, and spiral finned tube carries out compound water cooling with water cooled membrane wall to burner hearth, makes The fibre selection of burner hearth outlet flue is below 950 °C.

Spiral finned tube is made up of helix fin tube body and fin, and helix fin tube body and fin use a kind of metal Material is integrally formed by hot rolling technology, and by multiple roll-in formed uniform pitch spiral finned tube, fin section into It is trapezoidal, fin helix fin tube body axial direction into spiral yarn shaped.

Also include being used for the supercharging water injector for strengthening cooling water circulation flowing velocity in spiral finned tube；

Supercharging water injector includes the first mounting bracket, the second mounting bracket, two feed pumps and two feed pipes, the first installation Frame and the second mounting bracket are arranged at lower drum inner bottom part, and two feed pipes are along the direction with lower drum centerline parallel under Drum rearward end is extend into lower drum, and two feed pipes are separately mounted on the first installation by U-bolt, pad and nut On frame and the second mounting bracket, the closure of the front end of feed pipe, the water inlet of every feed pipe rear end is corresponding with feed pump Delivery port connects, and is respectively arranged with a control valve outside boiler body on two feed pipes, two feed pipes it Between connected by some connecting tubes, wherein some playpipes are connected with a feed pipe along its length, every injection The jet of pipe is corresponding with a helix fin infratubal port, between the jet and helix fin infratubal port of playpipe away from It is 3-5mm from the internal diameter for 2-4mm, the jet of playpipe.

Spiral finned tube is used from burner mounting hole to the direction of burner hearth outlet flue gradually from sparse to dense again to thin cloth Put mode, the water pipe of spiral finned tube and water cooled membrane wall is interval-staggered.

It is in bulk in the burner hearth surrounding water cooled membrane pars intramuralis of oil-burning gas-fired boiler, arrangement installation using above-mentioned technical proposal Water cooling tube, equivalent to a water-cooled furnace is added on the basis of original burner hearth, in order to make full use of the limited sky of burner hearth Between, the water cooling tube of arrangement uses spiral finned tube, and spiral finned tube is formed using overall hot rolling, increases the heat-absorbent surface of fire side Product, in order to not influence the heat absorption of water cooled membrane wall, the fin outer of the spiral finned tube of arrangement is at least more than one apart from membrane wall The caliber of the water pipe of individual membrane wall, and the water pipe of spiral finned tube and water cooled membrane wall is interval-staggered, spiral finned tube Quantity be advisable so that the temperature in burner hearth is reduced to less than 950 DEG C, such temperature can be very good to control nitrogen oxides Produce, while and can arranges superheater in burner hearth outlet flue, avoids because the thermic load of superheater is too big, superheated steam heat absorption energy Power is poor and causes booster, due to sufficiently make use of the space of radiation heat transfer in burner hearth, can be increased without burner hearth and boiler Volume, when maintaining same exhaust gas temperature, it is possible to reduce the arrangement of convection bank between upper drum and lower drum, reduce pot The steel consumption of stove and the overall weight of boiler and volume.

Specific increase boiler extension water-cooled furnace method is as follows：In the water cooled membrane wall of burner hearth surrounding, against water cooled membrane The place of wall, increase water cooling tube, form internal separate tube burner hearth, and original water cooled membrane wall forms the stove of compound water-cooling structure Thorax, internal water cooling tube can be light pipe or extended surface tube composition, and the utility model preferentially uses globality spiral finned tube, such a Spiral finned tube forms spiral finned tube, helix fin tube body and fin by hot rolling technology, and by multiple roll-in Integrally formed, between fin and helix fin tube body without welding therefore material it is identical, fin section in echelon, fin Helix fin tube body axial direction into spiral yarn shaped, such a structure is beneficial to the diffusion of heat and disturbing when flue gas conducts heat It is dynamic, therefore the heat transfer coefficient of spiral finned tube is very high, unit length heat transfer area is big, can be arranged in limited space less Spiral finned tube quantity increase heating surface area but at double.Because oil-burning gas-fired boiler is with upper drum and lower drum arrangement Structure, directly spiral finned tube can be through among upper drum and lower drum, using plug in construction, spiral finned tube it is upper End and bottom penetrate drum wall and are deep into inside drum, so can ensure spiral finned tube in upper pot in boiler operatiopn End in cylinder and lower drum is buried in water, ensures the safety heat exchange of upper drum and lower drum when carrying out radiation heat transfer, spiral shell Rotation extended surface tube is connected by the way of being welded inside drum using closing with drum, and the length that spiral finned tube is stretched into inside drum should It is advisable no more than 10mm, the fin outer for the spiral finned tube arranged inside burner hearth is at least more than one apart from burner hearth membrane wall The caliber of the water pipe of membrane wall, the quantity of spiral finned tube are advisable so that the temperature in boiler furnace is reduced to less than 950 degree（This On the one hand individual temperature can meet radiation heat transfer, and can reduces the generation of oxynitrides）, while the strong of boiler drum should be met Degree requires, after meeting both the above requirement, the spiral finned tubes of internal layer burner hearths should be arranged as far as possible, in order to not influence fuel more Ignition temperature, the arrangement quantity of spiral finned tube should be suitably reduced near burner mounting hole, in installation water cooled membrane wall During the spiral finned tube of inner side, it should be assembled in place prior to water cooled membrane wall.

Because the heat transfer in burner hearth belongs to radiant heat transfer, calorific intensity is big, in order to increase the security of water circulation, in internal layer stove Arrangement supercharging water injector, sets control valve, this control valve is being transported on feed pipe at the helix fin infratubal port of thorax Keep standard-sized sheet during row, the resistance of water spray how much by water jet size Control, control valve is closed in boiler shutdown, Playpipe is set on feed pipe, and the jet of playpipe is corresponding with helix fin infratubal port, the jet distance of playpipe Helix fin infratubal port is maintained at that 3mm or so is preferable, and it is preferable that the jet size of playpipe is generally kept in 3-5mm, allows spray Penetrate the water under high pressure that the jet of pipe gushes out（The meter per second of flow velocity about 5）, the Water circulation hydrodynamics being likely to occur to spiral finned tube are insufficient Compensation is provided, ensures the high reliability of spiral finned tube water circulation, so as to be easier to reduce the temperature in burner hearth.In addition, this reality With it is new it is middle use two feed pumps and two feed pipes, and connected between two feed pipes by some connecting tubes, this Sample can not only greatly enhance the flow velocity that playpipe sprays water, and when a feed pump breaks down or overhauled, another Work is can also continue to, so that the uninterrupted progress of the operation of pressurized water, it is ensured that big fluctuation does not occur for the temperature in burner hearth.

After compound water-cooled furnace, if boiler carries superheater, superheater can be directly arranged at furnace outlet, Without first arranging convection bank in furnace outlet by original arrangement, superheater is then arranged again, facilitates superheater Installation and check, for same boiler export flue-gas temperature, the volume of boiler with less arrangement convection bank, can be reduced, The overall steel consumption of boiler is reduced, but does not reduce the overall performance of boiler.

In summary, the utility model reduces the temperature of burner hearth when not increasing boiler volume or even reducing boiler volume And the temperature of furnace outlet, reduce the growing amount of boiler heating power type nitrogen oxides, facilitate the arrangement of superheater, reduce pot Stove entirety steel consumption.

Brief description of the drawings

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

Fig. 2 is Fig. 1 top view；

Fig. 3 is Fig. 1 left view；

Fig. 4 is the enlarged drawing that water injector is pressurized in Fig. 3；

Fig. 5 is the mplifying structure schematic diagram of spiral finned tube in Fig. 2；

Fig. 6 is the profile of the fin of spiral finned tube in Fig. 5.

Embodiment

As shown in figs 1 to 6, the gas fuel boiler of the present utility model with compound water-cooled furnace, including boiler body 1, the inner right side of boiler body 1 is burner hearth 2, and 1 anterior right side opening of boiler body is provided with burner mounting hole 3, the surrounding inwall of burner hearth 2 Water cooled membrane wall 4 is provided with, the left side of boiler body 1 is provided with upper drum 5 and lower drum 6, and upper drum 5 and lower drum 6 are by right Flowing bundle 7 connects, and burner hearth outlet flue 23 is arranged on the rear portion of water cooled membrane wall 4 in the left side of burner hearth 2, upper drum 5 and lower drum 6 it Between and be provided with superheater 8 at the burner hearth outlet flue 23, the left side front portion of boiler body 1 is provided with boiler nozzle 9, burner hearth 2 The inner side of water cooled membrane wall 4 of surrounding is evenly arranged with some spiral finned tubes 10, and water cooled membrane wall 4 is encircled into outer burner hearth, this A little spiral finned tubes 10 are encircled into internal furnace, water cooled membrane wall 4 and spiral finned tube 10 and Compound Water black furnace are formed in burner hearth 2 Thorax, every spiral finned tube 10 vertical direction arrangement, spiral finned tube 10 and water cooled membrane between upper drum 5 and lower drum 6 The distance of wall 4 is more than the water pipe caliber of water cooled membrane wall 4, and the upper end of all spiral finned tubes 10 is extend into upper drum 5, The lower end of all spiral finned tubes 10 is extend into lower drum 6, and spiral finned tube 10 extend into upper drum 5 and lower drum 6 Interior length is not more than 10mm；When installing boiler, spiral finned tube 10 assembles in place prior to water cooled membrane wall 4, helix fin Pipe 10 carries out compound water cooling with water cooled membrane wall 4 to burner hearth 2, makes the fibre selection of burner hearth outlet flue 23 below 950 °C.

Spiral finned tube 10 is made up of helix fin tube body 11 and fin 12, and helix fin tube body 11 and fin 12 are adopted It is integrally formed with a kind of metal material by hot rolling technology, and the spiral finned tube of uniform pitch is formed by multiple roll-in 10, the section of fin 12 in echelon, fin 12 helix fin tube body 11 axial direction into spiral yarn shaped.

Also include being used for the supercharging water injector 13 for strengthening cooling water circulation flowing velocity in spiral finned tube 10；

Supercharging water injector 13 includes the first mounting bracket 14,15, two feed pumps 16 of the second mounting bracket and two feed pipes 17, the first mounting bracket 14 and the second mounting bracket 15 are arranged at the inner bottom part of lower drum 6, two feed pipes 17 edge and lower drum 6 The direction of centerline parallel is extend into lower drum 6 by the rearward end of lower drum 6, and two feed pipes 17 pass through U-bolt 18, pad And nut 19 is separately mounted on the first mounting bracket 14 and the second mounting bracket 15, the front end closure of feed pipe 17, every water supply The water inlet of the rear end of pipe 17 is corresponding to be connected with the delivery port of a feed pump 16, and one is respectively arranged with two feed pipes 17 The individual control valve 22 outside the boiler body 1, connected by some connecting tubes 20 between two feed pipes 17, wherein one Some playpipes 21, the jet and a helix fin of every playpipe 21 are connected with root feed pipe 17 along its length The lower port of pipe 10 is corresponding, and the distance between the jet of playpipe 21 and the lower port of spiral finned tube 10 are 2-4mm, playpipe 21 The internal diameter of jet be 3-5mm.

Spiral finned tube 10 is using gradual from sparse to dense again to thin from burner mounting hole 3 to the direction of burner hearth outlet flue 23 Arrangement, the water pipe of spiral finned tube 10 and water cooled membrane wall 4 is interval-staggered.

Inside the surrounding water cooled membrane wall 4 of burner hearth 2 of oil-burning gas-fired boiler, arrangement installs water cooling tube in bulk, equivalent to A water-cooled furnace 2 is added on the basis of original burner hearth 2, in order to make full use of the limited space of burner hearth 2, the water cooling of arrangement Pipe uses spiral finned tube 10, and spiral finned tube 10 is formed using overall hot rolling, increases the endotherm area of fire side, in order to not The heat absorption of water cooled membrane wall 4 is influenceed, the outer of spiral finned tube 10 of arrangement is at least more than the water of a membrane wall apart from membrane wall The caliber of pipe, and the water pipe of spiral finned tube 10 and water cooled membrane wall 4 is interval-staggered, the quantity of spiral finned tube 10 with Temperature in burner hearth 2, which is reduced to less than 950 DEG C, to be advisable, and such temperature can be very good to control the generation of nitrogen oxides, together When and can burner hearth outlet flue 23 arrange superheater 8, avoid because the thermic load of superheater 8 is too big, superheated steam heat absorption capacity Difference and cause booster, due to sufficiently make use of the space of radiation heat transfer in burner hearth 2, burner hearth 2 and boiler can be increased without Volume, when maintaining same exhaust gas temperature, it is possible to reduce the arrangement of convection bank 7 between upper drum 5 and lower drum 6, drop The steel consumption of low boiler and the overall weight of boiler and volume.

The specific increase boiler extension method of water-cooled furnace 2 is as follows：In the water cooled membrane wall 4 of the surrounding of burner hearth 2, against water cooling film The place of formula wall 4, increase water cooling tube, form internal separate tube burner hearth 2, and original water cooled membrane wall 4 forms compound water-cooling structure Burner hearth 2, internal water cooling tube can be light pipe or extended surface tube composition, and the utility model preferentially uses globality spiral finned tube 10, such a spiral finned tube 10 forms spiral finned tube 10, spiral finned tube by hot rolling technology, and by multiple roll-in Body 11 and fin 12 are integrally formed, and without welding, therefore material is identical between fin 12 and helix fin tube body 11, The section of fin 12 in echelon, fin 12 helix fin tube body 11 axial direction into spiral yarn shaped, such a structure is beneficial to heat The disturbance when diffusion of amount and flue gas conduct heat, therefore the heat transfer coefficient of spiral finned tube 10 is very high, unit length heat transfer area is big, The increase heating surface area of the less quantity of helix fin tube body 11 but at double can be arranged in limited space.Due to fuel oil Gas fired-boiler is with upper drum 5 and the arrangement of lower drum 6, spiral finned tube 10 directly can be through upper drum 5 with Among drum 6, using plug in construction, the upper and lower end of spiral finned tube 10 penetrates drum wall and is deep into drum It portion, so can ensure that spiral finned tube 10 is buried in water in the end of upper drum 5 and lower drum 6 in boiler operatiopn, protect The safety heat exchange of upper drum 5 and lower drum 6 when carrying out radiation heat transfer is demonstrate,proved, spiral finned tube 10 is inside drum using closing weldering The mode connect connects with drum, and the length that spiral finned tube 10 is stretched into inside drum should be advisable no more than 10mm, inside burner hearth 2 The fin outer of the spiral finned tube 10 of arrangement is at least more than the caliber of the water pipe of a membrane wall, spiral shell apart from the membrane wall of burner hearth 2 The quantity of rotation extended surface tube 10 is advisable so that the temperature in boiler furnace 2 is reduced to less than 950 degree（On the one hand this temperature can expire Sufficient radiation heat transfer, and can reduce the generation of oxynitrides）, while the intensity requirement of boiler drum should be met, more than satisfaction two After kind requires, the spiral finned tubes 10 of internal layer burner hearths 2 should be arranged as far as possible more, in order to not influence the ignition temperature of fuel, Burner mounting hole 3 nearby should suitably reduce the arrangement quantity of spiral finned tube 10, the spiral in the inner side of installation water cooled membrane wall 4 During extended surface tube 10, it should be assembled in place prior to water cooled membrane wall 4.

Because the heat transfer in burner hearth 2 belongs to radiant heat transfer, calorific intensity is big, in order to increase the security of water circulation, in internal layer Arrangement supercharging water injector 13, sets control valve 22 on feed pipe 17 at the lower port of spiral finned tube 10 of burner hearth 2, this control Valve 22 processed keeps standard-sized sheet in the process of running, the resistance of water spray how much by water jet size Control, the handle in boiler shutdown Control valve 22 is closed, and playpipe 21, jet and the lower port of spiral finned tube 10 of playpipe 21 are set on feed pipe 17 Corresponding, the jet of playpipe 21 is maintained at 3mm or so preferably apart from the lower port of spiral finned tube 10, the jet of playpipe 21 Size is generally kept in the water under high pressure that 3-5mm is preferable, allows the jet of playpipe 21 to gush out（The meter per second of flow velocity about 5）, to spiral The Water circulation hydrodynamics deficiency that extended surface tube 10 is likely to occur provides compensation, ensures the high reliability of the water circulation of spiral finned tube 10, from And it is easier to reduce the temperature in burner hearth 2.In addition, two feed pumps 16 and two feed pipes 17 are used in the utility model, and And connected between two feed pipes 17 by some connecting tubes 20, it so can not only greatly enhance playpipe 21 and spray water Flow velocity, and when a feed pump 16 breaks down or overhauled, another can also continue to work, so that the work of pressurized water The uninterrupted progress of industry, it is ensured that big fluctuation does not occur for the temperature in burner hearth 2.

The present embodiment not makees any formal limitation, every foundation to shape of the present utility model, material, structure etc. Any simple modification, equivalent change and modification that the technical essence of the utility model is made to above example, belongs to this reality With the protection domain of new technique scheme.

Claims (4)

1. the gas fuel boiler with compound water-cooled furnace, including boiler body, boiler body inner right side is burner hearth, boiler Body portion right side opening is provided with burner mounting hole, and burner hearth surrounding inwall is provided with water cooled membrane wall, set on the left of boiler body There are upper drum and lower drum, upper drum is connected with lower drum by convection bank, and burner hearth outlet flue is arranged on the water on the left of burner hearth Cold membrane wall rear portion, superheater, boiler body left side are provided between upper drum and lower drum and at burner hearth outlet flue Front portion is provided with boiler nozzle, it is characterised in that：Some spirals are evenly arranged with the inside of the water cooled membrane wall of burner hearth surrounding Extended surface tube, water cooled membrane wall are encircled into outer burner hearth, and these spiral finned tubes are encircled into internal furnace, water cooled membrane wall and helix fin Pipe is in freeze profile into compound water-cooled furnace, and every spiral finned tube vertical direction between upper drum and lower drum is arranged, spiral shell The water pipe caliber that the distance between extended surface tube and water cooled membrane wall is more than water cooled membrane wall is revolved, the upper end of all spiral finned tubes is equal It extend into upper drum, the lower end of all spiral finned tubes is extend into lower drum, and spiral finned tube extend into upper drum It is not more than 10mm with the length in lower drum；When installing boiler, spiral finned tube assembles in place prior to water cooled membrane wall, spiral Extended surface tube carries out compound water cooling with water cooled membrane wall to burner hearth, makes the fibre selection of burner hearth outlet flue below 950 °C.

2. the gas fuel boiler according to claim 1 with compound water-cooled furnace, it is characterised in that：Spiral finned tube It is made up of helix fin tube body and fin, helix fin tube body and fin pass through hot rolling technology using a kind of metal material It is integrally formed, and the spiral finned tube of uniform pitch is formed by multiple roll-in, in echelon, fin is in helix fin for fin section The axial direction of tube body is into spiral yarn shaped.

3. the gas fuel boiler according to claim 1 with compound water-cooled furnace, it is characterised in that：Also include being used for Strengthen the supercharging water injector of cooling water circulation flowing velocity in spiral finned tube；

Supercharging water injector includes the first mounting bracket, the second mounting bracket, two feed pumps and two feed pipes, the first mounting bracket with Second mounting bracket is arranged at lower drum inner bottom part, and two feed pipes are along the direction with lower drum centerline parallel by lower drum Rearward end is extend into lower drum, two feed pipes by U-bolt, pad and nut be separately mounted on the first mounting bracket and On second mounting bracket, the front end closure of feed pipe, the water inlet corresponding water outlet with a feed pump of every feed pipe rear end Mouth is connected, and a control valve outside boiler body is respectively arranged with two feed pipes, is led between two feed pipes The connection of some connecting tubes is crossed, wherein some playpipes are connected with a feed pipe along its length, every playpipe Jet is corresponding with a helix fin infratubal port, and the distance between the jet of playpipe and helix fin infratubal port are 2-4mm, the internal diameter of the jet of playpipe is 3-5mm.

4. the gas fuel boiler according to claim 1 with compound water-cooled furnace, it is characterised in that：Spiral finned tube Using from burner mounting hole to the direction of burner hearth outlet flue gradually from sparse to dense again to thin arrangement, spiral finned tube with The water pipe of water cooled membrane wall is interval-staggered.