A whitewashing powder concentrate mother liquor tail gas heat utilization system

Abstract

The utility model discloses a kind of bleaching powder concentrate mother liquor tail gas heat utilization system, belong to sodium method bleaching powder concentrate device engineering design and production operation technical field.Wet material inlet pipeline is connected with feeder, the output end of the feeder is sequentially connected with cyclone separator and cloth bag dust collector by rotary flash dryer, the output end of the cloth bag dust collector is connected with tail gas heat exchanger, and the output pipeline of air inlet pipeline is also connected with tail gas heat exchanger;The output end of tail gas heat exchanger is sequentially connected with air heat exchanger and rotary flash dryer by pipeline.The utility model utilizes tail gas to preheat air, can reduce the steam consumption needed for heating air, and reduce the equipment scale of air heat exchanger.

Description

Technical Field

[0001] This utility model belongs to the technical field of engineering design and production operation of sodium bleaching powder equipment, and relates to a system for utilizing the heat of tail gas from bleaching powder mother liquor. Background Technology

[0002] Bleaching powder has strong bactericidal, disinfectant, purifying, and bleaching properties, and is widely used in industries such as wool washing, textiles, carpets, and papermaking. The product is generally in the form of white powder, solid granules, or tablets.

[0003] In the sodium process for producing bleaching powder, product drying is a crucial step in obtaining the finished bleaching powder tablets. The process generally includes drying, dust removal, and dust washing. The drying process consumes a large amount of heat, and simultaneously, the exhaust gas after dust removal enters the washing tower before cooling down, where the heat is diluted in the washing liquid and not fully utilized. Utility Model Content

[0004] The purpose of this invention is to provide a system for utilizing the heat of tail gas from bleaching powder mother liquor, which solves the problems existing in the prior art.

[0005] The technical solution adopted in this utility model (invention) is as follows:

[0006] A system for utilizing the heat of tail gas from bleaching powder mother liquor includes a wet material inlet pipe connected to a feeder. The output end of the feeder is connected in sequence to a cyclone separator and a bag filter via a rotary flash dryer. The output end of the bag filter is connected to a tail gas heat exchanger. The output pipe of the air inlet pipe is also connected to the tail gas heat exchanger. The output end of the tail gas heat exchanger is connected in sequence to an air heat exchanger and a rotary flash dryer via pipes.

[0007] In the above system, the exhaust gas heat exchanger also has an output that is connected to the flue gas scrubbing tower via a dry exhaust gas fan.

[0008] In the above system, the output ends of the cyclone separator and the bag filter are connected to the drying process.

[0009] In the above system, the air heat exchanger is equipped with steam pipes and condensate pipes.

[0010] In the above system, the flue gas scrubbing tower is equipped with a scrubbing liquid inlet pipe at the top and a scrubbing liquid outlet pipe at the bottom.

[0011] A heat utilization system for tail gas from bleaching powder mother liquor mainly comprises: a wet material inlet pipe, a flash evaporation material pipe, a separation gas pipe, a dust removal tail gas pipe, a separation material pipe, a dust recovery pipe, a tail gas heat exchange pipe, an air inlet pipe, an air preheating pipe, a hot air pipe, a tail gas scrubbing pipe, a scrubbing liquid inlet pipe, a scrubbing liquid outlet pipe, a vent pipe, a steam pipe, a condensate pipe, a feeder, a rotary flash dryer, a cyclone separator, a bag filter, an air heat exchanger, a tail gas heat exchanger, a drying tail gas fan, and a flue gas scrubbing tower.

[0012] The wet material inlet pipe is connected to the feeder input end and enters the rotary flash dryer. The output end of the rotary flash dryer is connected to a cyclone separator via a flash material pipe. The upper output end of the cyclone separator is connected to a bag filter via a separation gas pipe. The upper output end of the bag filter is connected to the input end of the exhaust gas heat exchanger via a dust removal exhaust gas pipe. The separation material pipe at the lower output end of the cyclone separator and the dust recovery pipe at the lower output end of the bag filter are combined and sent out as dried material for the drying process. The air inlet pipe is connected to the input end of the exhaust gas heat exchanger. One output end of the exhaust gas heat exchanger is connected to the tube-side input end of the air heat exchanger via an air preheating pipe, and the other output end is connected to the drying exhaust gas fan via an exhaust gas heat exchange pipe. The tube-side output end of the air heat exchanger is connected to the rotary flash dryer via a hot air pipe. The steam pipe and condensate pipe are connected to the shell-side input and output ends of the air heat exchanger, respectively. The output end of the dry exhaust gas fan is connected to the lower input end of the flue gas scrubbing tower via the exhaust gas scrubbing pipe. The upper input end of the flue gas scrubbing tower is connected to the scrubbing liquid inlet pipe. The vent pipe and the scrubbing liquid outlet pipe are respectively connected to the upper and lower output ends of the flue gas scrubbing tower.

[0013] In this utility model's technical solution: exhaust gas preheats air, avoiding heat waste and reducing steam consumption. The beneficial effects of this utility model (invention) are:

[0014] (1) Using exhaust gas to preheat air can reduce the steam consumption required to heat the air and reduce the equipment size of the air heat exchanger. (2) Make full use of the waste heat of exhaust gas to avoid heat waste. Attached Figure Description

[0015] Figure 1 This is a flowchart illustrating the present invention.

[0016] In the diagram, 1. Wet material inlet pipe, 2. Flash material pipe, 3. Separated gas pipe, 4. Dust removal exhaust gas pipe, 5. Separated material pipe, 6. Dust recovery pipe, 7. Exhaust gas heat exchange pipe, 8. Air inlet pipe, 9. Air preheating pipe, 10. Hot air pipe, 11. Exhaust gas scrubbing pipe, 12. Scrubbing liquid inlet pipe, 13. Scrubbing liquid outlet pipe, 14. Vent pipe, 15. Steam pipe, 16. Condensate pipe, 17. Feeder, 18. Rotary flash dryer, 19. Cyclone separator, 20. Bag filter, 21. Air heat exchanger, 22. Exhaust gas heat exchanger, 23. Drying exhaust gas fan, 24. Flue gas scrubbing tower. Detailed implementation method:

[0017] like Figure 1 As shown, a bleaching powder mother liquor tail gas heating system comprises a wet material inlet pipe 1, a flash evaporation material pipe 2, a separation gas pipe 3, a dust removal tail gas pipe 4, a separation material pipe 5, a dust recovery pipe 6, a tail gas heat exchange pipe 7, an air inlet pipe 8, an air preheating pipe 9, a hot air pipe 10, a tail gas scrubbing pipe 11, a scrubbing liquid inlet pipe 12, a scrubbing liquid outlet pipe 13, a vent pipe 14, a steam pipe 15, a condensate pipe 16, a feeder 17, a rotary flash dryer 18, a cyclone separator 19, a bag filter 20, an air heat exchanger 21, a tail gas heat exchanger 22, a drying tail gas fan 23, and a flue gas scrubbing tower 24.

[0018] The wet material inlet pipe 1 is connected to the input end of the feeder 17 and enters the rotary flash dryer 18. The output end of the rotary flash dryer 18 is connected to the cyclone separator 19 via the flash material pipe 2. The upper output end of the cyclone separator 19 is connected to the bag filter 20 via the separation gas pipe 3. The upper output end of the bag filter 20 is connected to the input end of the exhaust gas heat exchanger 22 via the dust removal exhaust gas pipe 4. The separation material pipe 5 at the lower output end of the cyclone separator 19 and the dust recovery pipe 6 at the lower output end of the bag filter 20 are combined and sent out as dried material for the drying process. The air inlet pipe 8 is connected to the input end of the exhaust gas heat exchanger 22. One output end of the exhaust gas heat exchanger 22 is connected to the tube-side input end of the air heat exchanger 21 via the air preheating pipe 9, and the other output end is connected to the drying exhaust gas fan 23 via the exhaust gas heat exchange pipe 7. The tube-side output of air heat exchanger 21 is connected to rotary flash dryer 18 via hot air pipe 10. Steam pipe 15 and condensate pipe 16 are connected to the shell-side input and output of air heat exchanger 21, respectively. The output of dryer exhaust fan 23 is connected to the lower input of flue gas scrubbing tower 24 via exhaust gas scrubbing pipe 11. The upper input of flue gas scrubbing tower 24 is connected to scrubbing liquid inlet pipe 12. Vent pipe 14 and scrubbing liquid outlet pipe 13 are connected to the upper and lower outputs of flue gas scrubbing tower 24, respectively.

[0019] Instructions for running the example:

[0020] In a typical bleaching powder manufacturing process, wet material from the reaction step enters the drying step and undergoes flash drying to obtain dry material. The dry material and exhaust gas are then separated by cyclone separation and baghouse dust collection. The dry material enters the packaging step for granulation and storage, while the exhaust gas is treated in a flue gas scrubbing tower. The hot air required for the rotary flash drying of the wet material is obtained through steam heat exchange. Drying 2426 kg / h of wet material with a water content of 45% wt requires 2 t / h of steam to heat the air.

[0021] In this case, waste heat from exhaust gas is used to preheat air. The pretreated air has a temperature of 25℃, a pressure of 0.0051 MPaG, a flow rate of 38157 kg / h, and a composition of 4% wt H2O, 73% wt N2, and 23% wt O2. The exhaust gas has a temperature of 70℃, a pressure of -0.005 MPaG, a composition similar to air, and a flow rate of 39249 kg / h. After heat exchange, the temperature is reduced to approximately 40℃. This provides approximately 0.5 tons of steam in heat.

Claims

1. A system for utilizing the heat from the tail gas of bleaching powder mother liquor, characterized in that, The wet material inlet pipe is connected to the feeder (17). The output end of the feeder (17) is connected to the cyclone separator (19) and the bag filter (20) in sequence through the rotary flash dryer (18). The output end of the bag filter (20) is connected to the exhaust gas heat exchanger (22). The output pipe of the air inlet pipe (8) is also connected to the exhaust gas heat exchanger (22). The output end of the exhaust gas heat exchanger (22) is connected to the air heat exchanger (21) and the rotary flash dryer (18) in sequence through pipes.

2. The bleaching powder mother liquor tail gas heat utilization system according to claim 1, characterized in that, The exhaust heat exchanger (22) also has an output that is connected to the flue gas scrubbing tower (24) via a dry exhaust gas fan (23).

3. The bleaching powder mother liquor tail gas heat utilization system according to claim 1, characterized in that, The output ends of the cyclone separator (19) and the bag filter (20) are connected to the drying process.

4. The bleaching powder mother liquor tail gas heat utilization system according to claim 1, characterized in that, The air heat exchanger (21) is equipped with a steam pipe (15) and a condensate pipe (16).

5. The bleaching powder mother liquor tail gas heat utilization system according to claim 1, characterized in that, The flue gas scrubbing tower (24) is provided with a scrubbing liquid inlet pipe (12) at the top and a scrubbing liquid outlet pipe (13) at the bottom.

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