Disclosure of Invention
In order to solve the problems in the prior art, the invention provides an external telescopic fire tube type normal pressure hot water boiler, in which the technologies of external fire tube, fire tube cooling, novel telescopic fire tube and the like are used, so that combustion substances are secondarily mixed in the combustion process, the combustion intensity is reduced, and the NO is reduced by controlling the combustion environment temperature x The purpose of high heat efficiency and low nitrogen emission is achieved.
The external fire tube part is of a jacket type container structure and comprises a burner, a zoom type fire tube, a jacket outer cylinder and a water inlet pipe, wherein the jacket outer cylinder is used for sleeving the zoom type fire tube inside, the zoom type fire tube and the water inlet pipe are arranged at intervals, and a jacket space is formed in the middle of the jacket outer cylinder; the scaling fire tube comprises an expansion section and a contraction section which are alternately arranged.
Further, the boiler main body part comprises a boiler barrel and a smoke outlet pipe at the top of the boiler barrel, the inside of the boiler barrel is sequentially provided with a water tank area, a smoke distribution area, a heat exchange area and a spraying area from bottom to top, wherein,
the water tank area comprises a water outlet pipe arranged at the lower part of the water tank area and a flue gas communicating pipe from the external fire tube part;
the smoke distribution area comprises a smoke distribution cylinder, the lower part of which is connected with the smoke communicating pipe, and a waterproof cap, which is arranged at the upper end of the smoke distribution cylinder;
the heat exchange area comprises a filler grid plate and a filler arranged on the filler grid plate;
the spraying area comprises a spraying pipe row arranged at the upper part of the spraying area, a top connecting pipe connected with the spraying pipe row and a silk screen foam remover arranged at the top opening part in the boiler barrel.
Further, the boiler barrel is of a metal cylinder structure; the boiler main body part also comprises a blow-down valve, a hand hole, a detection hole and a temperature, water level and water inflow monitoring device.
Further, the main body part of the boiler also comprises a blow-down valve, a hand hole, a detection hole and a temperature, water level and inflow monitoring device.
Further, the main body part of the boiler also comprises an automatic control device and a safety device, so that water level monitoring, low water level alarming and shutdown are realized; the burner can be used for adjusting the combustion intensity or stopping according to the water inflow.
Further, the outside of the boiler main body part and/or the external fire tube part adopts a heat insulation material so as to reduce heat loss.
The specific structure and the functions of each part of the external zoom fire tube type normal pressure hot water boiler are specifically described below.
The invention provides an external zoom fire tube type normal pressure hot water boiler, which uses gas fuel to provide hot water for heating, bathing and other working conditions. The external shrinkage fire tube type normal pressure hot water boiler comprises a boiler main body part (I) and an external fire tube part (II) connected with the side surface of the boiler main body part.
(I) The boiler main body part comprises a boiler barrel and a smoke outlet pipe at the top of the boiler barrel. The boiler barrel is internally provided with a water tank area, a flue gas distribution area, a heat exchange area and a spraying area from bottom to top in sequence. Wherein:
1. the water tank region includes:
the water outlet pipe is arranged at the lower part of the water tank area and is used for outputting hot water;
the flue gas communicating pipe is from external firetube part, transversely gets into the water tank from the water tank lower part, then upwards extends, and the terminal is connected with the flue gas distribution section of thick bamboo, submergence in water completely for the circulation of burning flue gas and carry out heat transfer with the water outside the pipe wall.
2. The flue gas distribution area comprises:
the flue gas distribution cylinder is vertically arranged in the flue gas distribution area, the lower part of the flue gas distribution cylinder is connected with the flue gas communicating pipe, and the upper part of the flue gas distribution cylinder extends out of the highest liquid level surface of the water tank, concentrates flue gas and conveys the flue gas to the heat exchange area;
the waterproof cap is arranged at the upper end of the smoke distributing cylinder and used for preventing spray water from entering the smoke distributing cylinder and the smoke communicating pipe.
3. The heat exchange zone comprises:
a packing grid plate installed at the lower portion of the heat exchange area for carrying packing thereon;
the filler is arranged on the filler grid and used for heat transfer;
in one embodiment, a baffle ring is also arranged around the inner wall of the boiler barrel at the upper part of the heat exchange area, and is of an annular structure and used for limiting the top of the filler.
4. The spraying area comprises:
the spray pipe row is arranged at the upper part of the spray area and consists of a plurality of groups of pipes containing nozzles, and one end of the spray pipe row is connected with the top connecting pipe and is used for spraying the filler by the inlet water;
one end of the top connecting pipe is connected with the spray pipe row, and the other end of the top connecting pipe penetrates through the boiler barrel body to be connected with the external fire pipe part and is used for introducing inlet water from the external fire pipe part into the spray pipe row;
the silk screen demister is arranged at the top opening in the boiler barrel and is used for removing residual mist carried by flue gas.
The smoke outlet pipe at the top of the boiler barrel is correspondingly arranged with the top opening, and the filtered smoke is discharged from the smoke outlet pipe.
In one embodiment, a wire mesh demister may also be disposed inside the flue tube.
In one embodiment, the boiler barrel is a metallic cylindrical structure.
In one embodiment, the flue gas distribution cylinder adopts a method for increasing the volume and the total area of the openings at the flue gas outlet end, thereby increasing the aperture and reducing the outlet speed of the flue gas. And the holes adopt a downward inclined structure, so that the filler can be prevented from being directly blown, and the spray water can be prevented from entering the flue gas distribution cylinder.
In one embodiment, the wall of the flue gas distribution cylinder is provided with a plurality of holes which incline downwards, and the included angle between the central axis of the holes and the side wall of the flue gas distribution cylinder is 50-70 degrees; in a preferred embodiment, the central axis of the opening is at an angle of 55 ° to 65 ° to the side wall of the flue gas distributor drum; in a preferred embodiment, the central axis of the opening is at an angle of 60 ° to the side wall of the flue gas distributor drum.
The packing can be stainless steel structured packing or stainless steel stepped ring random packing; in one embodiment, the packing adopts stainless steel structured packing, preferably stainless steel pore plate corrugated packing, and has the functions of large gas-liquid contact area, small resistance, good water and gas distribution performance, easy membrane growth, high strength, bubble cutting and the like. Of course, other fillers known in the art for heat exchange of hot water boilers may also be used.
In one embodiment, the boiler body portion further includes conventional boiler accessories such as a blow down valve, hand hole, sensing hole, and temperature, water level and inflow monitoring devices.
(II) the external fire tube part is of a jacket type container structure and comprises a burner, a zoom type fire tube, a jacket outer barrel and a water inlet pipe, wherein:
a jacket outer cylinder which is used for sleeving the zoom type fire tube inside, and is arranged at intervals, and a jacket space is formed in the middle of the jacket outer cylinder and used for accommodating water inflow; the upper part of the jacket outer cylinder is connected with the top connecting pipe, and the lower part of the jacket outer cylinder is connected with the water inlet pipe, so that water enters the jacket space from the water inlet pipe and enters the spray pipe row through the top connecting pipe;
the top of the scaling fire tube is connected with the burner, and the bottom of the scaling fire tube is connected with the flue gas communicating tube, and is used for circulating combustion flame and flue gas and exchanging heat with water outside the tube wall; the scaling fire tube comprises an expansion section and a contraction section which are alternately arranged.
The burner can be a variable-frequency burner, adopts gas fuel and provides heat energy for water inflow;
and the water inlet pipe is connected with the jacket outer cylinder and is used for providing water (cold water).
In one embodiment, the outer diameter of the expansion section is a constant value Φ, and the vertical height of each contraction section is 2 Φ/3 to Φ/3, preferably Φ/2; the maximum depth of radial contraction of the contraction section relative to the expansion section towards the inside of the fire tube is phi/10 to phi/6, preferably phi/8; the vertical distance from the bottom of the contraction section at the maximum depth of radial contraction of the contraction section relative to the expansion section toward the inside of the fire tube is from Φ/12 to Φ/8, preferably Φ/10.
In one embodiment, the outer diameter of the expansion section is a constant value phi, the vertical height of each contraction section is phi/2, the maximum depth of the contraction section relative to the radial contraction of the expansion section towards the inside of the fire tube is phi/8, and the vertical distance from the bottom of the contraction section at the maximum depth of the contraction section relative to the radial contraction of the expansion section towards the inside of the fire tube is phi/10.
In the technical scheme of the invention, the scaling fire tube comprises an expansion section and a contraction section, and the expansion section and the contraction section are alternately arranged. The setting of the zoom type fire tube has directivity, and adopts the principle of rapid expansion and shrinkage. The flame of the burner can be rapidly diffused to the periphery when being advanced after being sprayed, the shape of the rapid expansion and shrinkage of the wall of the fire tube can simultaneously generate disturbance to the flame in the downward direction and the transverse vertical direction, and the gas at the edge continuously and obliquely impacts the middle part, so that the gas in the fire tube is secondarily mixed and the combustion is more sufficient. Meanwhile, as the wall temperature suddenly drops due to the contact between the outer wall of the fire tube and cold water, the central flame temperature can be conducted to the cold water by the wall-side flame in the disturbance process, so that the internal temperature of the fire tube is wholly reduced, and a large amount of nitrogen oxides NO can not be generated due to severe combustion x Thereby reducing NO in the flue gas x Is contained in the composition. Because of the rapid expansion and slow contraction flow mode of the scaling fire tube, the fire tubeThe internal resistance is not so great as to affect the sufficiency of combustion. The directivity of the zoom type structure enables the airflow to be in smooth transition while being disturbed, and noise can be effectively reduced.
In addition, the scaled structure of the fire tube can cause strong disturbance of the medium (flame, smoke, water) locally due to asymmetry of expansion and contraction. In the process of flowing cold water from bottom to top outside the fire tube, a baffle plate or a spiral belt is not required to be arranged in the jacket for strengthening turbulence, and the scaling structure of the tube wall can enable the cold water to flow uniformly in the jacket. In addition, the scaling structure of the pipe wall can increase the scouring of cold water to the pipe wall, and is not easy to scale. According to experimental data, the heat exchange capacity of the scaling structure is improved by 20% -50% compared with that of the light pipe.
The fire tube is cooled and the inlet water is preheated. The cold water is preheated by the jacket type container structure, the heat exchange of the flue gas communicating pipe and the filler in the water tank is carried out for three-stage heating, and the heat transfer speed is 1.5-2 times of that of other boilers.
In the above-described solution, the fire tube is not located in the main body of the boiler, but is connected to the main body portion of the boiler as a separate unit. The shape, diameter, length and the like of the fire tube are not limited by the main body part any more, and can be independently set according to actual combustion working conditions.
In the scheme, the zoom type fire tube and the jacket outer cylinder form a jacket type container structure, and the temperature in the fire tube is reduced through the structure. The zoom type fire tube is always in a jacket water cooling environment.
The gas fuel used by the external zoom fire tube type normal pressure hot water boiler comprises natural gas, biogas, liquefied petroleum gas, coal gas, hydrogen and the like, and from the aspects of environmental protection and safety, the natural gas and the biogas are preferred, and the natural gas is more preferred.
In one embodiment, the boiler system of the present invention comprises an automatic control device and a safety device, which enable water level monitoring, low water level warning and shutdown. The burner in the boiler system of the invention can be used for adjusting the combustion intensity or stopping according to the water inflow.
In one embodiment, the boiler body portion of the hot water boiler and/or the exterior of the external fire tube is provided with insulation to reduce heat loss. The heat insulating material may be rock wool, aluminum silicate fiber cotton, chloric acid rate fiber cotton, glass fiber cotton, etc. or heat insulating mineral wool board and heat insulating cement may be used.
Compared with the prior art, the external zoom fire tube type normal pressure hot water boiler has the following effects:
1. the heat exchange efficiency can reach 92% -97%;
2. NO under the same combustion condition x The emission is reduced by more than 30 percent compared with the same type of boiler;
3. the water temperature is rapidly increased, and the temperature rise speed is 1.5-2 times of that of other boilers;
4. the noise is reduced by more than 20 db under the same burner.
Detailed Description
The operation flow of the equipment is divided into a combustion flow and a water flow, and for the purpose, the technical scheme and the characteristics of the invention are more clear, the operation flow is respectively described in different flow with reference to the accompanying drawings. The following is illustrative of the invention and is not intended to limit the scope of the invention.
Referring to fig. 1, the combustion process of the device operation is: the gas and air are mixed and combusted by the burner 12 to form flame and smoke gas, the flame and the smoke gas enter the scaling fire tube 13 and run downwards, then the smoke gas enters the water tank at the lower part of the boiler barrel 2 through the smoke gas communicating tube 3 and upwards enters the smoke gas distributing cylinder 4 through the water tank, the top of the smoke gas distributing cylinder 4 is provided with a waterproof cap 5 to prevent spray water from entering the smoke gas distributing cylinder 4, the smoke gas distributing cylinder 4 smoothly outputs the smoke gas, the smoke gas passes through the filler grid plate 6 and uniformly enters the filler 7, the filler 7 is placed on the filler grid plate 6, the top of the filler 7 is limited by the baffle ring 8, the smoke gas is in contact with the spray water from the spray tube row 9 in the filler 7 to transfer heat, then the entrained mist is removed through the wire mesh mist eliminator 10, and finally the smoke gas is discharged into the atmosphere through the smoke outlet tube 11 and a chimney.
The water course is as follows: cold water enters through a water inlet pipe 15 at the lower part of an external fire tube, rises along a jacket space between a zoom fire tube 13 and a jacket outer cylinder 14, takes away part of heat of smoke through the tube wall of the zoom fire tube 13, reduces the temperature of the fire tube 13, enters a spray tube row 9 at the upper part of the jacket space through a top connecting tube, sprays the filler 7 through a nozzle of the spray tube row 9, performs contact heat exchange with the smoke on the surface and the inside of the filler 7, finally falls into a water tank at the lower part of a boiler tube 2 and is provided for a user through a water outlet pipe 1 at the lower part of the water tank.
In a specific embodiment, the flue gas distribution cylinder is shown in a partial enlarged view in fig. 3, so that the volume of the flue gas outlet end and the total area of the openings are increased, the aperture is increased, and the outlet speed of the flue gas is reduced. And the holes adopt a downward inclined structure, so that the filler can be prevented from being directly blown, and the spray water can be prevented from entering the flue gas distribution cylinder. As shown in fig. 3, the wall of the flue gas distribution cylinder is provided with a plurality of holes which incline downwards, and the included angle between the central axis of the holes and the side wall of the flue gas distribution cylinder is 60 degrees.
In a specific embodiment, the proportional relation between the sizes of the contraction section and the expansion section of the wall of the scaled fire tube is shown in fig. 2, the outer diameter of the expansion section is a fixed value phi, the vertical height of each contraction section is phi/2, the maximum depth of the contraction section relative to the expansion section, which contracts radially inwards the fire tube, is phi/8, and the vertical distance from the bottom of the contraction section at the maximum depth of the contraction section relative to the expansion section, which contracts radially inwards the fire tube, is phi/10.
In one embodiment, the boiler system of the present invention comprises a sophisticated automatic control device and safety device, which enables water level monitoring, low water level alarm and shut down. The burner in the boiler system of the invention can be used for adjusting the combustion intensity or stopping according to the water inflow.
In one embodiment, the boiler system of the present invention comprises a blow down valve, hand hole, fire hole, etc., for ease of operation and maintenance.
In one embodiment, the boiler body portion of the hot water boiler and/or the exterior of the external fire tube is provided with insulation to reduce heat loss.
The external telescopic fire tube type normal pressure hot water boiler has the following characteristics: high efficiency, and the thermal efficiency reaches 92 to 97 percent; high environmental protection, nitrogen oxide NO x The emission is reduced by more than 30 percent compared with the same type of boiler; the reaction speed is high, and the temperature rise speed is 1.5-2 times of that of other boilers; low noise, and the noise is reduced by more than 20 dB under the same burner.
While the invention has been described in detail in the foregoing general description and specific examples, it will be apparent to those skilled in the art that modifications and improvements can be made thereto. Accordingly, such modifications or improvements may be made without departing from the spirit of the invention and are intended to be within the scope of the invention as claimed.