CN217209449U

CN217209449U - Cold air circulation backflow preheating system for high-temperature air preheater

Info

Publication number: CN217209449U
Application number: CN202221122619.6U
Authority: CN
Inventors: 刘凯珉
Original assignee: Qingdao Kaiweibao Technology Co ltd
Current assignee: Qingdao Kaiweibao Technology Co ltd
Priority date: 2022-05-11
Filing date: 2022-05-11
Publication date: 2022-08-16
Anticipated expiration: 2032-05-11

Abstract

The utility model discloses a high temperature air preheater is with cold air circulation backward flow system of preheating, including main air duct and pre-heater upper portion shell, be connected with main air duct reducer pipe on the main air duct, and the other end of main air duct reducer pipe is connected with venturi, fixed mounting has the cold air import on the lateral wall of pre-heater upper portion shell upper end, fixed mounting has the hot-air outlet on the lateral wall of pre-heater upper portion shell lower extreme, fixed mounting has the heat exchange tube in the shell of pre-heater upper portion. Has the advantages that: adopt the import cold air to preheat the mobile mode of circulation on air heater for improve the temperature of preheater import air, reduce the heat transfer difference in temperature of cold medium and hot medium, can improve the inside and outside difference in temperature of each part on preheater upper portion, reduce the thermoelectric corrosion and weaken expend with heat and contract with cold effect, improve the life of preheater, thereby reduced the maintenance frequency of preheater, guaranteed the steady operation of equipment.

Description

Cold air circulation backflow preheating system for high-temperature air preheater

Technical Field

The utility model relates to a heat exchange technology field especially relates to a high temperature air is cold air circulation backward flow system of preheating for preheater.

Background

In the production process of the carbon black by the oil furnace method, air needs to enter a reaction furnace for supporting combustion, the higher the temperature of the air entering the reaction furnace is, the less fuel is needed by the carbon black generation reaction, so the air is preheated by carbon black flue gas, the energy is fully recycled, the production cost can be reduced, and the economic benefit is improved.

The air preheater adopts a counter-flow design for absorbing and releasing heat media, so that a higher heat transfer driving force is obtained, the heat of the flue gas is efficiently transferred to the air through the tubes, the temperature of the flue gas is reduced, the consumption of quenching water is reduced, and the heat value of the carbon black tail gas is improved; the heat content of the air is improved after the air absorbs heat, and the consumption of the fuel oil of the reaction furnace is reduced under the same process conditions, so that the energy consumption is reduced, and the yield of the carbon black is improved. The air preheater has become an indispensable device for energy-saving recovery of waste heat in the carbon black industry and the industries of steel, power generation, chemical engineering and the like.

As energy recovery equipment, the heat exchange effect of the air preheater is important. Each manufacturer is dedicated to research on how to improve the heat exchange effect of the preheater to ensure the stable operation of the preheater, so as to better meet the requirements of the manufacturers. How to improve the heat exchange effect or ensure the stable operation of the preheater on the basis of the prior equipment and reduce the maintenance frequency becomes an important research subject.

The information disclosed in this background section is only for enhancement of understanding of the general background of the invention and should not be taken as an acknowledgement or any form of suggestion that this information constitutes prior art already known to a person skilled in the art.

SUMMERY OF THE UTILITY MODEL

The utility model aims at solving the problems existing in the prior art and providing a cold air circulation reflux preheating system for a high-temperature air preheater.

In order to achieve the above purpose, the utility model adopts the following technical scheme:

a cold air circulation reflux preheating system for a high-temperature air preheater comprises a main air pipeline and a shell at the upper part of the preheater, wherein the main air pipeline is connected with a reducing pipe of the main air pipeline, and the other end of the main air pipeline reducer is connected with a Venturi tube, a cold air inlet is fixedly arranged on the side wall of the upper end of the upper shell of the preheater, a hot air outlet is fixedly arranged on the side wall of the lower end of the upper shell of the preheater, a heat exchange tube is fixedly arranged in the upper shell of the preheater, a middle hot air outlet is fixedly arranged on the side wall of the middle end of the upper shell of the preheater, and the hot air outlet at the middle part is communicated with a hot air branch pipeline, the side wall of the Venturi tube is fixedly provided with a side inlet of the Venturi tube, and the lateral inlet of the Venturi tube is communicated with the hot air branch pipeline, and the upper end of the Venturi tube is communicated with the cold air inlet through a connecting pipe.

In the above cold air circulation and backflow preheating system for the high-temperature air preheater, the main air pipeline is provided with the main air pipeline adjusting valve.

In the cold air circulation reflux preheating system for the high-temperature air preheater, the pipe diameter of the venturi pipe is larger than that of the reducing pipe of the main air pipeline.

In the cold air circulation and backflow preheating system for the high-temperature air preheater, the outlet end of the venturi tube is communicated with the multi-wave pipeline expansion joint, and the multi-wave pipeline expansion joint is communicated with the cold air inlet.

In the cold air circulation reflux preheating system for the high-temperature air preheater, the baffle plate is fixedly arranged in the shell at the upper part of the preheater, and the thermometer interface is arranged on the hot air outlet.

In the cold air circulation reflux preheating system for the high-temperature air preheater, the hot air branch pipeline is provided with the pipeline expansion joint, and the hot air branch pipeline is provided with the hot air branch pipeline adjusting valve.

In the cold air circulation reflux preheating system for the high-temperature air preheater, the hot air branch pipeline, the venturi tube and the connecting pipe are all sleeved with the heat insulation sleeves.

Compared with the prior art, the utility model discloses the advantage lies in:

1: adopt the import cold air to preheat the mobile mode of circulation on air heater for improve the temperature of preheater import air, reduce the heat transfer difference in temperature of cold medium and hot medium, can improve the inside and outside difference in temperature of each part on preheater upper portion, reduce the thermoelectric corrosion and weaken expend with heat and contract with cold effect, improve the life of preheater, thereby reduced the maintenance frequency of preheater, guaranteed the steady operation of equipment.

2: the air preheater mainly adopts a single-pipe expansion structure, so that after the temperature of inlet air of the preheater is increased, the temperature difference between the inside and the outside of the single-pipe expansion joint is reduced, thereby reducing the temperature difference corrosion of the expansion joint and prolonging the service life of the expansion joint.

3: the inlet air temperature of the preheater is increased, the internal and external pressure difference at the upper part of the preheater is reduced, the leakage rate is reduced, and the sealing device of the preheater is enhanced.

To sum up, the utility model discloses adopt the import cold air to preheat the mobile mode of circulation on air heater for improve the temperature of preheater import air, reduce the heat transfer difference in temperature of cold medium and hot medium, can improve the inside and outside difference in temperature of each part on preheater upper portion, reduce the temperature difference corrosion and weaken expend with heat and contract with cold effect, improve the life of preheater, thereby reduced the maintenance frequency of preheater, guaranteed the steady operation of equipment.

Drawings

Fig. 1 is a schematic structural view of a cold air circulation and backflow preheating system for a high-temperature air preheater according to the present invention;

fig. 2 is a schematic cross-sectional view of a-a in fig. 1.

In the figure: the heat exchange system comprises a main air pipeline 1, a main air pipeline adjusting valve 2, a main air pipeline reducing pipe 3, a Venturi pipe 4, a multiwave pipeline expansion joint 5, a cold air inlet 6, a Venturi pipe side inlet 7, a hot air branch pipeline adjusting valve 8, a hot air branch pipeline 9, a pipeline expansion joint 10, a thermometer interface 11, a hot air outlet in the middle 12, a baffle plate 13, an upper shell of a preheater 14, a hot air outlet 15 and a heat exchange pipe 16.

Detailed Description

The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative work belong to the protection scope of the present invention.

Referring to fig. 1-2, a cold air recirculation preheat system for a high temperature air preheater includes a main air duct 1 and a preheater upper shell 14.

The above is noteworthy:

1. be connected with main air duct reducing pipe 3 on the main air duct 1, and the other end of main air duct reducing pipe 3 is connected with venturi 4, fixed mounting has cold air inlet 6 on the 14 upper end lateral walls of pre-heater upper portion shell, and venturi 4's upper end is through connecting pipe and cold air inlet 6 intercommunication, and the process air flows in main air duct 1, and in the connecting pipe was gone into behind venturi 4, in the air heater of admitting air through cold air inlet 6 afterwards.

2. The diameter of the venturi tube 4 is larger than that of the reducer pipe 3 of the main air pipe, and the size of the venturi tube is designed to increase the flow rate of air in the venturi tube 4, so as to generate micro negative pressure in the venturi tube for sucking hot air from the middle of the air preheater.

3. The outlet end of the Venturi tube 4 is communicated with a multiwave pipeline expansion joint 5, the multiwave pipeline expansion joint 5 is communicated with a cold air inlet 6, and the multiwave pipeline expansion joint 5 is designed to eliminate the expansion and contraction effect of the pipeline.

4. Fixed mounting has hot-air outlet 15 on the 14 lower extreme lateral walls of pre-heater upper portion shell, fixed mounting has heat exchange tube 16 in the 14 upper portion shell of pre-heater, fixed mounting has middle part hot-air outlet 12 on the middle part lateral wall of pre-heater upper portion shell 14, and the intercommunication has hot-air branch pipeline 9 on the hot-air outlet 12 of middle part, fixed mounting has venturi side import 7 on venturi 4's the lateral wall, and venturi side import 7 and hot-air branch pipeline 9 intercommunication, fixed mounting has baffling board 13 in the 14 upper portion shell of pre-heater.

5. After entering the air preheater, the process air is contacted with the heat exchange tube 16 for heat exchange and temperature rise, and is deflected by the baffle plate 13, flows downwards to reach the position of the middle hot air outlet 12 for shunting, most of the hot air continuously flows downwards to be heated to the required temperature, and is discharged out of the preheater from the hot air outlet 15, a small part of the hot air flows into the hot air branch pipeline 9 from the middle hot air outlet 12 and is finally connected with the side inlet 7 of the venturi tube, and the small part of the hot air is sucked by the venturi tube 4 to be mixed with the main process air, so that the temperature of the main process air is raised.

6. Install main air duct governing valve 2 on the main air duct 1, install pipeline expansion joint 10 on the hot-air branch pipeline 9, install hot-air branch pipeline governing valve 8 on the hot-air branch pipeline 9, pipeline governing valve 8 is used for adjusting the flow of the hot-air that flows out from air heater, can adjust the temperature of cold air import 6 department from this (pipeline governing valve 8 open the size with the temperature that does not influence pre-heater hot-air outlet 15 department as the benchmark adjustment), pipeline expansion joint 10 is used for eliminating hot-expanding cold-shrinking effect of hot-air branch pipeline 9, prevent the condition such as pipeline stretch-breaking.

7. The hot air outlet 15 is provided with a thermometer port 11, and the thermometer port 11 is used for detecting the temperature of the air flowing out from the middle hot air outlet 12 (where the temperature is related to the height of the position of the middle hot air outlet 12, the closer the middle hot air outlet 12 is to the cold air inlet 6, the lower the temperature).

8. The hot air branch pipeline 9, the Venturi tube 4 and the connecting pipe are all sleeved with heat insulation sleeves, and the heat insulation sleeves can prevent heat loss due to the design of the heat insulation sleeves.

In the utility model, the process air flows in the main air pipeline 1, enters the connecting pipe after the Venturi tube 4, then enters the air preheater through the cold air inlet 6, after the process air enters the air preheater, contacts with the heat exchange pipe 16 for heat exchange and temperature rise, and baffling by the baffle plate 13, the downward flow reaches the position of the hot air outlet 12 of the middle part for shunting, most of the hot air continues to flow downward and is heated to the required temperature, the preheater is discharged from the hot air outlet 15, a small part of the hot air flows into the hot air branch pipeline 9 from the hot air outlet 12 of the middle part, finally, the process air is connected with the Venturi tube side inlet 7, a small part of the hot air is sucked by the Venturi tube 4 and is mixed with the main process air, the temperature of the main process air is improved, thereby the temperature of the inlet air of the preheater can be improved, the heat exchange temperature difference between the cold medium and the hot medium is reduced, the inside and outside temperature difference of each part of the upper part of the preheater can be improved, the temperature difference corrosion is reduced, the expansion and contraction effect is weakened, the service life of the preheater is prolonged, the maintenance frequency of the preheater is reduced, and the stable operation of equipment is ensured.

The above, only be the concrete implementation of the preferred embodiment of the present invention, but the protection scope of the present invention is not limited thereto, and any person skilled in the art is in the technical scope of the present invention, according to the technical solution of the present invention and the utility model, the concept of which is equivalent to replace or change, should be covered within the protection scope of the present invention.

Claims

1. The utility model provides a cold air circulation backward flow preheats system for high temperature air preheater, includes main air duct (1) and pre-heater upper portion shell (14), its characterized in that, be connected with main air duct reducing pipe (3) on main air duct (1), and the other end of main air duct reducing pipe (3) is connected with venturi (4), fixed mounting has cold air inlet (6) on pre-heater upper portion shell (14) upper end lateral wall, fixed mounting has hot air outlet (15) on pre-heater upper portion shell (14) lower extreme lateral wall, fixed mounting has heat exchange tube (16) in pre-heater upper portion shell (14), fixed mounting has middle part hot air outlet (12) on the middle part lateral wall of pre-heater upper portion shell (14), and the intercommunication has hot air lateral conduit (9) on middle part hot air outlet (12), fixed mounting has venturi side import (7) on the lateral wall of venturi (4), and the venturi tube side inlet (7) is communicated with the hot air branch pipeline (9), and the upper end of the venturi tube (4) is communicated with the cold air inlet (6) through a connecting pipe.

2. A cold air recirculation preheating system for high temperature air preheaters according to claim 1, characterized in that the main air duct (1) is provided with a main air duct adjusting valve (2).

3. A cold air circulation and return preheating system for a high temperature air preheater according to claim 1, wherein the diameter of the venturi tube (4) is larger than that of the reducer pipe (3) of the main air pipeline.

4. A cold air circulation and backflow preheating system for a high-temperature air preheater according to claim 1, wherein the outlet end of the venturi tube (4) is communicated with a multi-wave pipeline expansion joint (5), and the multi-wave pipeline expansion joint (5) is communicated with the cold air inlet (6).

5. A cold air circulation and return preheating system for a high temperature air preheater according to claim 1, wherein a baffle plate (13) is fixedly installed in the upper housing (14) of the preheater, and a thermometer port (11) is provided on the hot air outlet (15).

6. A cold air recirculation preheating system for a high temperature air preheater according to claim 1, wherein the branch hot air conduit (9) is provided with a conduit expansion joint (10), and the branch hot air conduit (9) is provided with a branch hot air conduit regulating valve (8).

7. The cold air circulation and backflow preheating system for the high-temperature air preheater as claimed in claim 1, wherein the hot air branch pipe (9), the venturi tube (4) and the connecting pipe are all sleeved with insulation sleeves.