Tail gas waste heat recycling device for sodium benzoate production

Abstract

The utility model provides a tail gas waste heat recycling device for sodium benzoate production, which is characterized in that a tail gas heat exchanger is arranged between a washing tower and a tail gas induced draft fan, heat exchange tubes which are arranged in a crossed and staggered manner are arranged in the tail gas heat exchanger, and an air inlet below the tail gas heat exchanger is connected with a tail gas outlet of the washing tower; under the action of the tail gas induced draft fan, high-temperature tail gas containing sodium benzoate dust and water vapor enters the tail gas heat exchanger, heat in the high-temperature tail gas is transferred to compressed air in the heat exchange pipe, dust and water in the tail gas are condensed and settled, soft water leaches the dust attached to the heat exchange pipe through the distributor, and the tail gas is discharged. The condensate and the leacheate can further wash the tail gas of the washing tower, the water consumption of the washing tower is reduced, most of heat, dust and water vapor in the high-temperature tail gas are recycled through the tail gas heat exchanger, air pollution and dust emission are effectively reduced, energy conservation and environmental protection are achieved, the safety risk is low, the industrial production cost is effectively reduced, and industrial production is facilitated.

Description

Technical Field

[0001] The utility model relates to the technical field of chemical production, in particular to a tail gas waste heat recycling device for sodium benzoate production. Background Art

[0002] At present, the industrial production process of sodium benzoate produces high-temperature tail gas containing sodium benzoate dust, which is directly discharged after being washed and absorbed in a washing tower.

[0003] However, after the exhaust is absorbed by the scrubber, benzoic acid dust still remains. The exhaust also carries water vapor from the scrubber, wasting water resources. The exhaust contains a large amount of heat, which condenses in the air and releases sodium benzoate dust, causing environmental pollution and health risks. Furthermore, directly venting the high-temperature exhaust wastes a significant amount of heat, increasing industrial production costs.

[0004] In view of this, it is necessary to design an improved tail gas waste heat recycling device for sodium benzoate production to solve the above problems. Utility Model Content

[0005] In response to the above-mentioned defects of the prior art, the purpose of the present utility model is to provide a tail gas waste heat recycling device for sodium benzoate production, which can further treat the sodium benzoate dust in the tail gas, recover the heat and water in the tail gas, save energy and be environmentally friendly, have low safety risks, and effectively reduce industrial production costs.

[0006] To achieve the above-mentioned objectives, the present invention provides a tail gas waste heat recycling device for sodium benzoate production, comprising a washing tower and a tail gas heat exchanger connected to the washing tower, wherein a tail gas air inlet is provided at the bottom of the tail gas heat exchanger; the washing tower is connected to the tail gas air inlet pipeline; the tail gas heat exchanger includes a shell and a distributor located at the top end of the shell, and a plurality of cross-staggered heat exchange tubes located inside the shell.

[0007] As a further improvement of the present invention, the exhaust gas heat exchanger further includes a compressed air inlet located on the side of the shell, and the compressed air inlet is connected to the air compressor pipeline.

[0008] As a further improvement of the present invention, an air inlet is provided at one end of the air compressor.

[0009] As a further improvement of the present invention, the arrangement direction of the compressed air inlet is perpendicular to the exhaust direction of the exhaust gas.

[0010] As a further improvement of the present invention, a compressed air outlet is provided on the other side of the housing;

[0011] The device further includes a first heater connected to the compressed air outlet pipeline, and a second heater connected to the first heater, wherein the second heater is connected to the washing tower.

[0012] As a further improvement of the present invention, the device further includes a granulation bed plate between the washing tower and the second heater.

[0013] As a further improvement of the present invention, the exhaust gas heat exchanger further includes a soft water pipe located at the top end of the shell, and a soft water pipe regulating valve connected to the soft water pipe.

[0014] As a further improvement of the present invention, the exhaust gas heat exchanger further includes an exhaust gas outlet located at the top of the shell, and an induced draft fan connected to the exhaust gas outlet, and an exhaust gas discharge pipe is provided at one end of the induced draft fan.

[0015] As a further improvement of the present invention, the induced draft fan is connected to the exhaust gas outlet pipeline and an induced draft fan regulating valve is provided on the pipeline.

[0016] The beneficial effects of the utility model are:

[0017] The utility model provides a tail gas waste heat recycling device for sodium benzoate production, which is provided with a tail gas heat exchanger between a washing tower and a tail gas induced draft fan, wherein the tail gas heat exchanger is provided with heat exchange tubes arranged in a staggered manner, and the air inlet below the tail gas heat exchanger is connected to the tail gas outlet of the washing tower; in this way, under the action of the tail gas induced draft fan, high-temperature tail gas containing sodium benzoate dust and water vapor enters the tail gas heat exchanger, and when the high-temperature tail gas passes through the staggered heat exchange tubes, the heat in the high-temperature tail gas is transferred to the compressed air in the heat exchange tubes. The dust and water in the exhaust gas condense and settle, and some of the dust will adhere to the heat exchange tubes. The water and the other part of the dust fall back into the scrubbing tower by gravity. The soft water pipe regulating valve is opened, and the soft water is eluted through the distributor to wash the dust attached to the heat exchange tubes. The condensate and elution liquid can further wash the exhaust gas from the scrubber, reducing the water consumption of the scrubber. Most of the heat, dust and water vapor in the high-temperature exhaust gas are recovered through the exhaust gas heat exchanger, effectively reducing air pollution and dust emissions, and greatly reducing production investment costs and energy consumption. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is a schematic diagram of the overall structure of the tail gas waste heat recycling device for sodium benzoate production provided by the utility model.

[0019] Figure 2 This is a schematic structural diagram of the tail gas heat exchanger in the tail gas waste heat recycling device for sodium benzoate production provided by the utility model.

[0020] Reference numerals

[0021] 1. Air inlet; 2. Air compressor; 3. Compressed air inlet; 4. Compressed air outlet; 5. Exhaust gas outlet; 6. Exhaust gas inlet; 7. Distributor; 8. Soft water pipe regulating valve; 9. Soft water pipe; 10. Draft fan regulating valve; 11. Draft fan; 12. Exhaust gas discharge pipe; 13. Scrubber; 14. Granulation bed; 15. First heater; 16. Second heater; 17. Heat exchange tube; 18. Shell. DETAILED DESCRIPTION

[0022] In order to make the purpose, technical solutions and advantages of the present invention more clear, the present invention is described in detail below with reference to the accompanying drawings and specific embodiments.

[0023] It should also be noted here that, in order to avoid obscuring the present invention due to unnecessary details, only structures and / or processing steps closely related to the scheme of the present invention are shown in the accompanying drawings, while other details that are not closely related to the present invention are omitted.

[0024] In addition, it should be noted that the terms "comprises", "includes" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or apparatus that includes a series of elements includes not only those elements, but also includes other elements not explicitly listed, or also includes elements inherent to such process, method, article or apparatus.

[0025] The utility model provides a tail gas waste heat recycling device for sodium benzoate production, comprising a washing tower 13 and a tail gas heat exchanger connected to the washing tower 13, wherein a tail gas air inlet 6 is provided at the bottom of the tail gas heat exchanger; the washing tower 13 is connected to the tail gas air inlet 6 by a pipeline; the tail gas heat exchanger comprises a shell 18 and a distributor 7 located at the top end of the shell 18 and a plurality of cross-staggered heat exchange tubes 17 located inside the shell 18.

[0026] By recycling and reusing the waste heat from exhaust gases generated during the production process, energy consumption is reduced, production costs are lowered, and energy efficiency is improved. By reducing direct exhaust emissions, environmental pollution is mitigated, meeting the requirements of sustainable development.

[0027] Specifically, the exhaust gas heat exchanger also includes a compressed air inlet 3 located on the side of the shell 18, which is connected to the air compressor 2 pipeline; an air inlet 1 is provided at one end of the air compressor 2; the arrangement direction of the compressed air inlet 3 is perpendicular to the exhaust direction of the exhaust gas; a compressed air outlet 4 is provided on the other side of the shell 18 of the exhaust gas heat exchanger.

[0028] The exhaust heat exchanger also includes a soft water pipe 9 located at the top of the shell 18 and a soft water pipe regulating valve 8 connected to the soft water pipe 9. An exhaust outlet 5 is provided at the top of the shell 18. An induced draft fan 11 is connected to the exhaust outlet 5 by a pipeline, and an induced draft fan regulating valve 10 is installed on the pipeline. An exhaust gas discharge pipe 12 is provided at one end of the induced draft fan 11.

[0029] The introduction of compressed air can enhance the convective heat exchange between the exhaust gas and the heat exchange tube 17, and improve the heat exchange efficiency. The introduction of soft water can cool the exhaust gas, and at the same time, it can also clean certain pollutants in the exhaust gas, thereby improving the treatment effect of the exhaust gas. Through the soft water pipe regulating valve 8 and the induced draft fan regulating valve 10, the flow of soft water and exhaust gas can be accurately controlled to optimize the heat exchange process. By cooling and cleaning the exhaust gas, pollutant emissions can be reduced, meeting environmental protection requirements. By recovering the heat in the exhaust gas, energy waste is reduced and energy saving is achieved. The use of soft water can reduce corrosion inside the heat exchanger and extend the service life of the equipment. By adjusting the flow of compressed air and soft water, different production needs and environmental conditions can be adapted. The use of the induced draft fan 11 ensures that the exhaust gas can be discharged safely and effectively, and avoids the accumulation of exhaust gas inside the equipment.

[0030] The device also includes a first heater 15 connected to the compressed air outlet 4 by a pipeline, a second heater 16 connected to the first heater 15, and the second heater 16 connected to the scrubbing tower 13. A granulation bed 14 is also disposed between the scrubbing tower 13 and the second heater 16. The high-temperature heating provided by the first and second heaters 15, 16 maximizes the thermal energy in the exhaust gas, reducing energy consumption. The high-temperature compressed air is directly used to dry and granulate the sodium benzoate on the granulation bed 14, improving granulation efficiency and quality. The flow of high-temperature air ensures uniform drying of the sodium benzoate on the granulation bed 14, avoiding localized overheating or uneven drying.

[0031] The tail gas waste heat recycling device for sodium benzoate production provided by the present invention is described below with reference to specific embodiments.

[0032] Example

[0033] like Figure 1 As shown, this embodiment provides a tail gas waste heat recycling device for sodium benzoate production, including a washing tower 13 and a tail gas heat exchanger, wherein a tail gas air inlet 6 is provided at the bottom of the tail gas heat exchanger, and the tail gas in the washing tower 13 flows into the tail gas heat exchanger through the tail gas air inlet 6, and the tail gas heat exchanger is connected to the tail gas air inlet 6 by a pipeline, and the tail gas heat exchanger is configured to condense and settle the sodium benzoate dust in the tail gas to the washing tower 13 after heat exchange with water, and then discharge the tail gas, that is, after the sodium benzoate dust in the tail gas is removed by the tail gas heat exchanger, the remaining tail gas is discharged.

[0034] See also Figure 1As shown, the exhaust gas heat exchanger includes a shell 18 and a compressed air inlet 3, wherein the compressed air inlet 3 is located on the side of the shell 18, and the compressed air inlet 3 is connected to the air compressor 2 through a pipeline.

[0035] An air inlet 1 is provided at one end of the air compressor 2. External air enters through the air inlet 1 and is compressed by the air compressor 2. The compressed air then flows into the exhaust gas heat exchanger through the pipeline. At this time, the compressed air is mixed with the exhaust gas in the exhaust gas heat exchanger.

[0036] The arrangement direction of the compressed air inlet 3 is perpendicular to the exhaust direction of the exhaust gas.

[0037] A compressed air outlet 4 is provided on the other side of the shell 18 ; the device further includes a first heater 15 and a second heater 16 , wherein the first heater 15 is connected to the compressed air outlet 4 through a pipeline, and the second heater 16 is connected to the first heater 15 .

[0038] It should be noted that the device also includes a granulation bed plate 14 between the washing tower 13 and the second heater 16. Therefore, the compressed air is mixed with the exhaust gas in the exhaust gas heat exchanger and flows out through the compressed air outlet 4 and is heated at high temperature by the first heater 15 and the second heater 16 to form high-temperature compressed air, and finally flows into the granulation bed plate 14. The sodium benzoate in the granulation bed plate 14 is dried and granulated to form a high-temperature exhaust gas carrying a large amount of sodium benzoate dust. After the high-temperature exhaust gas is washed by the washing tower 13, most of the sodium benzoate dust is removed to form a high-temperature exhaust gas containing a small amount of sodium benzoate dust and a large amount of water vapor. The high-temperature exhaust gas passes through the exhaust gas inlet 6 and then enters the exhaust gas heat exchanger to form a cycle.

[0039] See also Figure 1 As shown, the exhaust gas heat exchanger also includes a soft water pipe 9 located at the top of the shell 18 and a soft water pipe regulating valve 8 connected to the soft water pipe 9, and also includes an exhaust gas outlet 5 located at the top of the shell 18 and an induced draft fan 11 connected to the exhaust gas outlet 5. An exhaust gas discharge pipe 12 is provided at one end of the induced draft fan 11. The induced draft fan 11 is connected to the exhaust gas outlet 5 by a pipeline and an induced draft fan regulating valve 10 is provided on the pipeline. After the sodium benzoate in the exhaust gas is condensed and settled in the exhaust gas heat exchanger, the induced draft fan 11 will discharge the exhaust gas with the sodium benzoate removed. In addition, the soft water pipe 9 can leach the residual sodium benzoate dust in the exhaust gas heat exchanger. Under the action of gravity, the sodium benzoate dust is eluted back into the washing tower 13.

[0040] The exhaust gas heat exchanger also includes a distributor 7 located at the top of the shell 18 and several cross-staggered heat exchange tubes 17 located inside the shell 18. The heat exchanger is used to fully exchange heat between compressed air and exhaust gas in the exhaust gas heat exchanger. The distributor 7 can evenly distribute the soft water flowing into the soft water pipe 9.

[0041] The working principle of this embodiment is as follows:

[0042] First, the air is compressed by the air compressor 2 and enters the exhaust gas heat exchange gas through the pipeline. The exhaust gas in the washing tower 13 is discharged into the exhaust gas heat exchanger. At this time, the compressed air and the exhaust gas are fully mixed in the exhaust gas heat exchanger. After sufficient heat exchange, cooling and condensation through the heat exchange tube 17 in the exhaust gas heat exchanger, the sodium benzoate dust in the exhaust gas condenses and settles and returns to the washing tower 13 by gravity, and the exhaust gas with sodium benzoate removed is discharged through the exhaust gas outlet 5 through the induced draft fan 11. In addition, when sodium benzoate dust remains in the exhaust gas heat exchanger, the soft water pipe 9 is opened, and the soft water is evenly distributed through the distributor 7 to flush and rinse the residual sodium benzoate dust. The rinsing liquid returns to the washing tower 13 at the same time under the action of gravity.

[0043] At the same time, after heat exchange, the compressed air is discharged through the compressed air outlet 4, heated by the first heater 15 and the second heater 16, and then enters the granulation bed 14 to dry and granulate the sodium benzoate, forming a high-temperature exhaust gas carrying a large amount of sodium benzoate dust. The high-temperature exhaust gas is washed by the scrubber 13 to remove most of the sodium benzoate dust, forming an exhaust gas containing a small amount of sodium benzoate dust and a large amount of water vapor. The exhaust gas enters the exhaust heat exchanger through the exhaust air inlet 6 to complete the circulation. The design of the utility model significantly improves the overall practicality and efficiency of the exhaust waste heat recycling device for sodium benzoate production.

[0044] The above embodiments are only used to illustrate the technical solution of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solution of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solution of the present invention.

Claims

1. A tail gas waste heat recycling device for sodium benzoate production, characterized in that: It includes a washing tower and an exhaust gas heat exchanger connected to the washing tower, wherein the exhaust gas heat exchanger is provided with an exhaust gas inlet at the bottom; the washing tower is connected to the exhaust gas inlet pipeline; The exhaust gas heat exchanger includes a shell, a distributor located at the top end of the shell, and a plurality of heat exchange tubes located inside the shell and arranged in a cross-staggered manner.

2. The tail gas waste heat recycling device for sodium benzoate production according to claim 1, characterized in that: The exhaust gas heat exchanger further includes a compressed air inlet located on the side of the shell, and the compressed air inlet is connected to the air compressor pipeline.

3. The tail gas waste heat recycling device for sodium benzoate production according to claim 2, characterized in that: An air inlet is provided at one end of the air compressor.

4. The tail gas waste heat recycling device for sodium benzoate production according to claim 2, characterized in that: The arrangement direction of the compressed air inlet is perpendicular to the exhaust direction of the exhaust gas.

5. The tail gas waste heat recycling device for sodium benzoate production according to claim 2, characterized in that: A compressed air outlet is provided on the other side of the shell of the exhaust gas heat exchanger.

6. The tail gas waste heat recycling device for sodium benzoate production according to claim 5, characterized in that: The device further comprises a first heater connected to the compressed air outlet pipeline, a second heater connected to the first heater, and the second heater is connected to the washing tower.

7. The tail gas waste heat recycling device for sodium benzoate production according to claim 6, characterized in that: The apparatus further includes a granulation bed plate between the washing tower and the second heater.

8. The tail gas waste heat recycling device for sodium benzoate production according to claim 2, characterized in that: The exhaust gas heat exchanger further includes a soft water pipe located at the top end of the shell and a soft water pipe regulating valve connected to the soft water pipe.

9. The tail gas waste heat recycling device for sodium benzoate production according to claim 2, characterized in that: The exhaust gas heat exchanger further includes an exhaust gas outlet located at the top end of the shell and an induced draft fan connected to the exhaust gas outlet, and an exhaust gas discharge pipe is provided at one end of the induced draft fan.

10. The tail gas waste heat recycling device for sodium benzoate production according to claim 9, characterized in that: The induced draft fan is connected to the exhaust gas outlet pipeline and an induced draft fan regulating valve is provided on the pipeline.

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