Low nitrogen hot water boiler

Abstract

The present invention provides a low-nitrogen hot water boiler, which belongs to the technical field of heating equipment. It includes a furnace body and a furnace, a heating chamber is formed between the furnace body and the furnace, a smoke exhaust chamber is provided in the furnace body near one end of the furnace entrance, a smoke collecting chamber is provided in the furnace body connected to the furnace exit, a plurality of smoke pipes are inserted in the heating chamber, the two ends of the smoke pipes are respectively connected to the smoke collecting chamber and the smoke exhaust chamber, the furnace entrance is connected to an air intake pipe, a gas supply pipe is rotatably connected in the air intake pipe, an impeller located in the smoke collecting chamber is fixedly provided on the gas supply pipe, a plurality of jet holes are provided on the gas supply pipe at the furnace entrance, and an ignition device is provided in the furnace outside the jet holes. The present invention has the advantages of being able to make the flame shape more conducive to improving the heat utilization rate.

Description

Technical Field

[0001] The invention belongs to the technical field of heating equipment and relates to a low-nitrogen hot water boiler. Background Art

[0002] Low-nitrogen boilers have better exhaust gas emission performance and are more in line with environmental protection and energy-saving requirements. However, existing boilers do not fully utilize flue gas. Most of them adopt the method of exhaust gas recirculation, which makes their structure complex and the circulation volume of exhaust gas difficult to control.

[0003] After the flue gas is discharged from the furnace, in addition to preheating the incoming air, it needs to be condensed and then discharged from the chimney. The heat utilization rate is low. The main reason is that it is difficult to balance the flue gas discharge efficiency and combustion efficiency. That is to say, if the flue gas is discharged too quickly, the combustion efficiency can be increased, but the heat loss is also large. If the flue gas is discharged too slowly, the heat utilization rate is higher, but the heat production efficiency will decrease. How to reduce the production of nitrogen oxides and increase the heat utilization rate without affecting the total heat generation is a design problem for the boiler. Summary of the invention

[0004] The purpose of the present invention is to provide a low-nitrogen hot water boiler in view of the above-mentioned problems existing in the prior art. The technical problem to be solved by the present invention is how to make the flame expand outward to increase the heat utilization rate.

[0005] The objectives of the present invention can be achieved through the following technical solutions: a low-nitrogen hot water boiler, comprising a furnace body and a furnace, characterized in that a heating chamber is formed between the furnace body and the furnace, the furnace body has a smoke exhaust chamber near one end of the furnace inlet, the furnace body has a smoke collecting chamber connected to the furnace outlet, a plurality of smoke pipes are inserted in the heating chamber, the two ends of the smoke pipes are respectively connected to the smoke collecting chamber and the smoke exhaust chamber, the inlet of the furnace is connected to an air inlet pipe, a gas supply pipe is rotatably connected to the air inlet pipe, an impeller located in the smoke collecting chamber is fixedly arranged on the gas supply pipe, the gas supply pipe has a plurality of jet holes located at the furnace inlet, and an ignition device is arranged in the furnace outside the jet holes.

[0006] The water inlet collecting chamber is connected to the cold water source, and the water outlet collecting chamber is connected to the hot water delivery pipe for use by water-using equipment. The cooled water can also be circulated back to the water inlet collecting chamber after use.

[0007] Furthermore, a plurality of flame dividing wheels are arranged outside the gas supply pipe, and the flame dividing wheels are arranged alternately.

[0008] Furthermore, the flame dividing wheel can guide the airflow to flow from the inlet to the outlet of the furnace.

[0009] Furthermore, the impeller is rotated by the hot gas at the furnace outlet and can drive the flue gas flow to disperse outside the impeller.

[0010] Based on the fact that increasing the air intake, extending the flame, and forming a hollow flame can have a positive effect on the thermal utilization rate of the boiler, the uniformity of heating of the heating medium, and the reduction of nitrogen oxide production, this scheme adopts a rotating gas supply pipe, and its rotational power comes from the exhaust gas impact force at the end of the furnace. The outer wall of the gas supply pipe is provided with a number of flame separation wheels located in the furnace. The flame separation wheel guides the mixed gas in the furnace during the rotation of the gas supply pipe, driving it to rush out of the end of the furnace at a faster speed, and can also make the flame tend to be distributed on the wall of the furnace. The traditional flame utilization rate in the middle of the furnace is low, and most of the heat exists in the flue gas. The concentrated flue gas affects the complete combustion and promotes a large number of incompletely burned intermediates. Through the rotation of the flame separation wheel, the flame is extended and supported from the inside and expanded outward, the inner wall of the furnace is heated more evenly, and the heating effect of the heating cavity is better.

[0011] The "prohibition of exhaust" of flue gas can also make the heat be absorbed by the heating medium in the heating chamber as much as possible.

[0012] In a traditional boiler, the flue gas discharged from the furnace hits the furnace wall at the end of the furnace and then returns to the exhaust pipe, causing part of the flue gas to choke back into the furnace, affecting the length of the flame in the furnace, especially the flame at the end of the furnace. In this solution, an impeller is provided to guide the flue gas so that it diffuses to the outside of the smoke collecting chamber and then better enters the exhaust pipe.

[0013] The hot gas in the furnace tends to be discharged in a spiral state under the rotation of the flame dividing wheel, especially at the end of the furnace, which can wash the inner wall of the furnace and reduce ash accumulation. The rotation of the gas supply pipe also generates centrifugal force during the discharge of gas, which makes it better blended with air or mixed gas and the gas mixing more evenly. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a structural diagram of the boiler when smoke discharge is not permitted.

[0015] Figure 2 It is a structural diagram of the boiler in the state of exhausting flue gas.

[0016] Figure 3 yes Figure 1 Enlarged view of part A in the figure.

[0017] Figure 4 yes Figure 2 Enlarged view of part B in the middle.

[0018] In the figure, 11, furnace body; 12, furnace chamber; 21, heating chamber; 22, smoke exhaust chamber; 23, air intake chamber; 24, smoke collecting chamber; 3, smoke pipe; 41, water distribution pipe; 42, water inlet collecting chamber; 43, water outlet collecting chamber; 51, air inlet pipe; 52, air inlet connecting pipe; 53, check valve; 54, piston; 55, reset spring; 61, gas supply pipe; 62, impeller; 63, jet hole; 7, ignition device; 8, smoke exhaust connecting pipe; 9, flame separation wheel. DETAILED DESCRIPTION

[0019] The following are specific embodiments of the present invention and the accompanying drawings to further describe the technical solution of the present invention, but the present invention is not limited to these embodiments.

[0020] like Figure 1 to Figure 4 As shown, it includes a furnace body 11 and a furnace 12, a heating chamber 21 is formed between the furnace body 11 and the furnace 12, the furnace body 11 has a smoke exhaust chamber 22 and an air intake chamber 23 near one end of the furnace 12 entrance, the furnace body 11 has a smoke collecting chamber 24 connected to the furnace 12 outlet, a plurality of smoke pipes 3 are inserted in the heating chamber 21, the two ends of the smoke pipes 3 are respectively connected to the smoke collecting chamber 24 and the smoke exhaust chamber 22, a plurality of water distribution pipes 41 are arranged in the heating chamber 21, the inlet of each water distribution pipe 41 is connected to a water inlet collection chamber 42 located on the outer wall of the furnace body 11, the outlet of each water distribution pipe 41 is connected to a water outlet collection chamber 43 located on the outer wall of the furnace body 11, and the heating chamber 21 is filled with a heating medium;

[0021] The entrance of the furnace 12 is connected to an air intake pipe 51, which is communicated with the air intake chamber 23. The air intake pipe 51 is also connected to an air intake connecting pipe 52, and the air intake connecting pipe 52 is connected to an oxygen supply source. A gas supply pipe 61 is rotatably connected in the air intake pipe 51, and an impeller 62 located in the smoke collecting chamber 24 is fixedly provided on the gas supply pipe 61. The gas supply pipe 61 has a plurality of jet holes 63 located at the entrance of the furnace 12, and an ignition device 7 is provided in the furnace 12 outside the jet holes 63.

[0022] A check valve 53 is provided in the air intake pipe 52, and the smoke exhaust chamber 22 and the air intake chamber 23 are separated by a piston 54. A return spring 55 is connected between the piston 54 and the furnace body 11. A smoke exhaust pipe 8 that can communicate with the smoke exhaust chamber 22 is provided on the furnace body 11, and the surrounding wall of the piston 54 can cover the entrance of the smoke exhaust pipe 8.

[0023] The water inlet collecting chamber 42 is connected to a cold water source, and the water outlet collecting chamber 43 is connected to a hot water delivery pipe for use by water-using equipment. The cooled water can also be circulated back to the water inlet collecting chamber 42 after use.

[0024] A plurality of flame dividing wheels 9 are arranged outside the gas supply pipe 61, and the flame dividing wheels 9 are arranged alternately.

[0025] The heating medium is water or other medium with a higher boiling point than water.

[0026] The flame dividing wheel 9 can guide the airflow to flow from the inlet to the outlet of the furnace 12 .

[0027] The impeller 62 is rotated by the hot gas at the outlet of the furnace 12 and can drive the flue gas to disperse toward the outside of the impeller 62 .

[0028] The water inlet collecting chamber 42 is arranged on the furnace body 11 near the inlet end of the furnace 12 , and the water outlet collecting chamber 43 is arranged on the furnace body 11 near the outlet end of the furnace 12 .

[0029] Based on the fact that increasing the air intake, extending the flame, and forming a hollow flame can have a positive effect on the thermal utilization rate of the boiler, the uniformity of the heating medium, and the reduction of the production of nitrogen oxides, this solution adopts a rotating gas supply pipe 61, and its rotational power comes from the exhaust gas impact force at the end of the furnace 12. The outer wall of the gas supply pipe 61 is provided with a plurality of flame separation wheels 9 located in the furnace 12. The flame separation wheels 9 guide the mixed gas in the furnace 12 during the rotation of the gas supply pipe 61, driving it to rush out of the end of the furnace 12 at a faster speed, thereby making the end of the intake pipe 51 A relative negative pressure is formed, which is relative to the case where the flame dividing wheel 9 is not provided. The increase in the air intake can promote more complete combustion of the gas, and the proportion of nitrogen oxides in the exhaust gas is relatively reduced. The flame can also be distributed on the wall of the furnace 12. The flame utilization rate in the middle of the traditional furnace 12 is low, and most of the heat exists in the flue gas. The concentrated flue gas affects the complete combustion and promotes a large number of incompletely burned intermediates. Through the rotation of the flame dividing wheel 9, the flame is extended and supported from the inside and expanded outward, the inner wall of the furnace 12 is heated more evenly, and the heating effect of the heating cavity 21 is better.

[0030] The present invention adopts an intermittent air intake and intermittent smoke exhaust method, so that part of the smoke can be burned for the second time. Specifically, when the pressure in the smoke exhaust chamber 22 is relatively small, the return spring 55 drives the piston 54 to approach the smoke exhaust chamber 22, and the circumference of the piston 54 blocks the entrance of the smoke exhaust pipe 8. The smoke is temporarily not allowed to be discharged. The smoke gathers in the smoke exhaust chamber 22 until the pressure in the smoke exhaust chamber 22 increases to the point where the piston 54 moves toward the air intake chamber 23. During the movement of the piston 54 toward the air intake chamber 23, the check valve 53 blocks the air intake chamber 23, and the air pressure therein increases and enters the furnace 12, which can achieve the effect of air intake pressurization. At the same time, as the piston 54 moves, the circumference of the piston 54 gradually "opens" the entrance of the smoke exhaust pipe 8, and the high-pressure smoke in the smoke exhaust chamber 22 is discharged. Since the smoke cannot be discharged in a short time, part of the smoke gathered in the furnace 12 is mixed with high-pressure fresh air and fuel gas, and can be burned again under the ignition state.

[0031] The "prohibition of exhaust" of flue gas can also make the heat be absorbed by the heating medium in the heating chamber 21 as much as possible. The agitated flue gas can also implement reverse cleaning of the smoke pipe 3 with a certain effect, thereby extending the maintenance period of dust accumulation in the smoke pipe 3.

[0032] When the piston 54 approaches the smoke exhaust chamber 22, fresh air is sucked into the air intake chamber 23. This part of the gas is preheated in the air intake chamber 23 close to the smoke exhaust chamber 22, and is squeezed into the furnace 12 when the piston 54 approaches the air intake chamber 23, thereby realizing automatic air intake. The air supply volume can be controlled by a pressure limiting valve arranged on the air intake path of the fresh air.

[0033] In a traditional boiler, the flue gas exhausted from the furnace 12 hits the furnace wall at the end of the furnace 12 and then returns to the exhaust pipe 3, causing part of the flue gas to choke back into the furnace 12, affecting the length of the flame in the furnace 12, especially the flame at the end of the furnace 12. In this solution, an impeller 62 is provided to guide the flue gas so that it diffuses toward the outside of the smoke collecting chamber 24, and then better enters the exhaust pipe 3.

[0034] The hot gas in the furnace 12 tends to be discharged in a spiral state under the rotation of the flame separation wheel 9, especially at the end of the furnace 12, which can wash the inner wall of the furnace 12 to reduce ash accumulation. During the discharge of the gas, the rotation of the gas supply pipe 61 also generates centrifugal force, which makes it better blended with air or mixed gas and makes the gas mixing more uniform.

[0035] The specific embodiments described herein are merely examples of the spirit of the present invention. Those skilled in the art may make various modifications or additions to the specific embodiments described or replace them in similar ways, but they will not deviate from the spirit of the present invention or exceed the scope defined by the appended claims.

Claims

1. A low-nitrogen hot water boiler, comprising a furnace body (11) and a furnace (12), It is characterized in that A heat receiving chamber (21) is formed between the furnace body (11) and the furnace (12), a plurality of water distribution pipes (41) are arranged in the heat receiving chamber (21), the entrance of the furnace (12) is connected to an air intake pipe (51), a gas supply pipe (61) is rotatably connected in the air intake pipe (51), an impeller (62) located in the smoke collecting chamber (24) is fixedly arranged on the gas supply pipe (61), a plurality of gas injection holes (63) are arranged at the entrance of the furnace (12), and an ignition device (7) is arranged in the furnace (12) outside the gas injection holes (63); The impeller (62) is rotated by the hot gas at the furnace (12) outlet and is capable of driving the flue gas to disperse toward the outside of the impeller (62); A plurality of flame separation wheels (9) are arranged outside the gas supply pipe (61), and the flame separation wheels (9) are arranged alternately; during the rotation of the gas supply pipe (61), the flame separation wheels (9) guide the mixed gas in the furnace (12), driving the mixed gas to rush out of the end of the furnace (12) at a faster speed, thereby forming a relative negative pressure at the end of the air inlet pipe (51); The furnace body (11) comprises a smoke exhaust chamber (22) and an air intake chamber (23) at one end close to the entrance of the furnace (12), and the furnace body (11) comprises a smoke collecting chamber (24) connected to the exit of the furnace (12). A plurality of smoke pipes (3) are inserted into the heating chamber (21), and the two ends of the smoke pipes (3) are respectively connected to the smoke collecting chamber (24) and the smoke exhaust chamber (22).

2. According to claim 1, a low nitrogen hot water boiler, It is characterized in that The flame separation wheel (9) is capable of guiding the airflow to flow from the inlet to the outlet of the furnace (12).

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