CN220119885U - Device for adjusting pH value of gas-based shaft furnace water system - Google Patents
Device for adjusting pH value of gas-based shaft furnace water system Download PDFInfo
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- CN220119885U CN220119885U CN202321467406.1U CN202321467406U CN220119885U CN 220119885 U CN220119885 U CN 220119885U CN 202321467406 U CN202321467406 U CN 202321467406U CN 220119885 U CN220119885 U CN 220119885U
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- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 title claims abstract description 107
- 238000005507 spraying Methods 0.000 claims abstract description 59
- 238000000034 method Methods 0.000 claims abstract description 56
- 239000007921 spray Substances 0.000 claims abstract description 44
- 238000001816 cooling Methods 0.000 claims abstract description 41
- 238000010926 purge Methods 0.000 claims description 18
- 230000001105 regulatory effect Effects 0.000 claims description 5
- 238000004519 manufacturing process Methods 0.000 abstract description 9
- 230000007797 corrosion Effects 0.000 abstract description 8
- 238000005260 corrosion Methods 0.000 abstract description 8
- 239000002253 acid Substances 0.000 abstract description 7
- 239000000463 material Substances 0.000 description 5
- 238000012544 monitoring process Methods 0.000 description 5
- 229910000831 Steel Inorganic materials 0.000 description 3
- 238000010586 diagram Methods 0.000 description 3
- 239000010959 steel Substances 0.000 description 3
- 229910000619 316 stainless steel Inorganic materials 0.000 description 2
- 238000007664 blowing Methods 0.000 description 2
- 230000007935 neutral effect Effects 0.000 description 2
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- 238000003723 Smelting Methods 0.000 description 1
- 230000002378 acidificating effect Effects 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000000740 bleeding effect Effects 0.000 description 1
- 229910052799 carbon Inorganic materials 0.000 description 1
- 239000013043 chemical agent Substances 0.000 description 1
- 239000000498 cooling water Substances 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000000945 filler Substances 0.000 description 1
- 238000012423 maintenance Methods 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 238000012797 qualification Methods 0.000 description 1
- 230000035484 reaction time Effects 0.000 description 1
- 238000004064 recycling Methods 0.000 description 1
- 238000003466 welding Methods 0.000 description 1
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- Gas Separation By Absorption (AREA)
Abstract
The utility model discloses a device for adjusting the PH value of a water system of a gas-based shaft furnace, which comprises the gas-based shaft furnace, a spraying device, a cooling tower, a compressor aftercooler and a booster pump; the process gas outlet of the gas-based shaft furnace is communicated with the cooling tower through a process gas pipeline, a spraying device is arranged on the process gas pipeline between the gas-based shaft furnace and the cooling tower, and the spraying device can spray into the process gas pipeline; the air outlet of the cooling tower is communicated with the air inlet of the compressor, and the air outlet of the compressor is communicated with an air inlet pipeline of the aftercooler of the compressor; and a cooling backwater outlet of the aftercooler of the compressor is communicated with an inlet of the spraying device through a booster pump. The device is characterized in that the backwater of the rear cooler of the compressor is completely used for spraying, the pH value of the water system is not changed, the spraying device is simple and easy to replace, the online replacement can be realized in the normal production process, the normal production is not influenced, the device has the characteristics of simple structure and convenient pH value control, and the acid corrosion of the water system is effectively avoided.
Description
Technical Field
The utility model relates to an auxiliary system of a gas-based shaft furnace, in particular to a device for adjusting the PH value of a water system of the gas-based shaft furnace.
Background
The environment-friendly situation of steel smelting is increasingly severe nowadays, and gas-based shaft furnace production is being developed vigorously in China in order to reduce carbon emission.
The process gas component after the gas-based shaft furnace is reacted contains CO 2 The water used for cooling the process gas of the gas-based shaft furnace absorbs a large amount of CO 2 The pH value of the water system is obviously lower, and the acidic water is easy to cause pipeline corrosion, so that a new device and a new method for adjusting the pH value of the water system are needed.
Disclosure of Invention
The utility model aims to provide a device for adjusting the pH value of a gas-based shaft furnace water system so as to effectively avoid acid corrosion of the water system.
In order to solve the technical problems, the utility model adopts the following technical scheme: the device comprises a gas-based shaft furnace, a spraying device, a cooling tower, a compressor aftercooler and a booster pump; the process gas outlet of the gas-based shaft furnace is communicated with the cooling tower through a process gas pipeline, a spraying device is arranged on the process gas pipeline between the gas-based shaft furnace and the cooling tower, and the spraying device can spray into the process gas pipeline; the air outlet of the cooling tower is communicated with the air inlet of the compressor, and the air outlet of the compressor is communicated with an air inlet pipeline of the aftercooler of the compressor; and a cooling backwater outlet of the aftercooler of the compressor is communicated with an inlet of the spraying device through a booster pump.
Further, the spraying device comprises a water drum, a branch water pipe, a spraying pipe and a high-pressure atomizing nozzle; the spray pipes are connected in series on the process gas pipeline, at least one high-pressure atomizing nozzle is arranged on the process gas pipeline, and a spray opening of the high-pressure atomizing nozzle extends into the spray pipes; the branch water pipes are the same in number and are communicated with the high-pressure atomizing nozzles in a one-to-one correspondence manner; the booster pump is communicated with the water drum, and the other ends of the branch water pipes are communicated with the water drum.
Furthermore, at least two sets of spraying devices are arranged, and each set of spraying device is arranged in parallel.
Furthermore, the spray pipe is provided with a blowing pipe and a blowing stop valve at the front end of the high-pressure atomizing nozzle, and a diffusing pipe and a diffusing stop valve at the rear end of the high-pressure atomizing nozzle.
Further, the device also comprises a water pump and a humidifier; and the water outlet of the cooling tower is communicated with the humidifier through a water pump.
The beneficial effects of adopting above-mentioned technical scheme to produce lie in: the utility model sprays the backwater of the aftercooler of the compressor into the process gas circulation system through the spraying device, and releases CO in the water through the high temperature and low pressure of the process gas system 2 The pH value of the backwater is raised to 6.4 to 6.7 and is close to neutral; and then the water in the process gas is removed through cooling of the cooling tower, so that the backwater of the aftercooler of the compressor is not circulated into the water system, and the acid corrosion of the water system is avoided. The back cooler backwater of the compressor is used for spraying, the pH value of the water system is not changed, the spraying device is simple and easy to replace, the online replacement can be realized in the normal production process, the normal production is not affected, and the back cooler backwater spraying device has the characteristics of simple structure and convenience in pH value control, and the acid corrosion of the water system is effectively avoided.
Drawings
The utility model will be described in further detail with reference to the drawings and the detailed description.
FIG. 1 is a schematic diagram of the structure of the present utility model;
FIG. 2 is a schematic diagram of the mechanism of the spraying device according to the present utility model;
FIG. 3 is a schematic view of the structure of the high pressure atomizing nozzle according to the present utility model;
FIG. 4 is a schematic diagram of the condensing and dehydrating process of the cooling tower according to the present utility model.
In the figure: 1. a booster pump; 16. CO number one 2 A monitor; 17. a first spray tube; 18. a second spray tube; 19. a front stop valve; 20. purging the stop valve; 21. a purge tube; 22. a high pressure atomizing nozzle; 23. a bleeding stop valve; 24. a diffusing pipe; 25. a rear shutoff valve; 26. CO No. two 2 A monitor; 27. a effluent pH monitor; 28. a gas-based shaft furnace; 28. a gas-based shaft furnace; 29. a spraying device; 30. a cooling tower; 31. a compressor; 32. a compressor aftercooler; 33. a water pump; 34. a humidifier.
Detailed Description
As shown in FIG. 1, the device for regulating the pH value of the water system of the gas-based shaft furnace comprises a gas-based shaft furnace 28, a spraying device 29, a cooling tower 30, a compressor 31, a compressor aftercooler 32 and a booster pump 1. The process gas outlet of the gas-based shaft furnace 28 is communicated with a cooling tower 30; the air outlet of the cooling tower 30 is communicated with the air inlet of the compressor 31, and the air outlet of the compressor 31 is communicated with the air inlet pipeline of the compressor aftercooler 32; a spraying device 29 is arranged on a process gas pipeline between the gas-based shaft furnace 28 and the cooling tower 30, and a spraying opening of the spraying device 29 can spray into the process gas pipeline; the cooling backwater outlet of the compressor aftercooler 32 is communicated with the inlet of the spraying device 29 through the booster pump 1. Also comprising a water pump 33 and a humidifier 34; the water outlet of the cooling tower 30 is communicated with a humidifier 34 through a water pump 33. After the structure is adopted, the gas composition of the gas-based shaft furnace process contains a large amount of CO and CO 2 After preliminary cooling and dedusting, the process gas enters a spraying device 29, the sprayed process gas contains a large amount of water, then enters a compressor 31 after condensing and removing the water by a cooling tower 30, and enters the gas-based shaft furnace again after boosting by the compressor 31 to finish recycling; the cooling water of the compressor aftercooler 32 is supplied by a water system, the interior of the compressor aftercooler is configured with an upper mounting orifice plate distributor, distributing water flow, a filler support grid in the middle, and an air inlet distributor in the lower, and the air is in direct contact with the water, which can cause backwater to absorb a large amount of CO 2 The backwater absorbs a large amount of CO 2 The pH value of the backwater is reduced to 3.9-4.2, the pH value of the backwater is obviously lower, backwater of the aftercooler 32 of the compressor is completely sprayed into a process gas circulation system through a spraying device 29, and CO in the water is released through high temperature and low pressure of the process gas system 2 Then, the pH value of the backwater is raised to 6.4-6.7 and is close to neutral, and then the backwater in the aftercooler 32 of the compressor is not circulated into the water system by cooling of the cooling tower to remove the water in the process gas, so that the acid corrosion of the water system is avoided.
The device for adjusting the PH value of the gas-based shaft furnace water system is characterized in that the booster pump 1 is communicated with a plurality of water bags through a water supply pipeline, and a bypass pipe and a bypass stop valve are arranged at the rear end of the water supply pipeline. The number of the spraying devices 29 is the same as that of the water bags, and all the spraying devices 29 are connected in parallel. As shown in fig. 2 and 3, the spraying device 29 of the device for regulating the pH value of the gas-based shaft furnace water system comprises a branch water pipe, a spraying pipe and a high-pressure atomizing nozzle 22; the following description will take two sets of spraying devices 29 and a water drum as shown in fig. 2 and 3 as an example. The number of the spraying pipes is two, namely a first spraying pipe 17 and a second spraying pipe 18; the first spray pipe 17 and the second spray pipe 18 are arranged in parallel and are connected in series on a process gas pipeline; a first CO is arranged on the process gas pipeline at the air inlet front end of the spray pipe 2 A monitor 16. Front stop valves 19 and purge pipes 21 are arranged at the front ends of the first spray pipe 17 and the second spray pipe 18, and purge stop valves 20 are arranged on the purge pipes 21; the rear ends of the first spray pipe 17 and the second spray pipe 18 are respectively provided with a diffusing pipe 24 and a rear stop valve 25, and the diffusing pipe 24 is provided with a diffusing stop valve 23. The two water bags are respectively communicated with a plurality of branch water pipes; each branch water pipe is communicated with a high-pressure atomizing nozzle 22 through flexible connection; the spray orifice of the high pressure atomizing nozzle 22 extends into the spray tube. A water pressure gauge, a quick-cut valve, a flow meter and a pH monitor are arranged on a water return pipeline between the water drum and the booster pump 1, and a stop valve and a branch flow meter are arranged on pipelines at the front ends of the two water drums; each branch water pipe is provided with a flow regulating valve and a branch pipe flowmeter.
As shown in FIG. 4, the device for regulating the PH value of the water system of the gas-based shaft furnace is characterized in that a second CO is arranged at the air outlet of the cooling tower 30 2 Monitor 26, outThe water gap is provided with a water outlet pH monitor 27.
Examples: the device for adjusting the pH value of the gas-based shaft furnace water system comprises three parts:
(1) The first part is a water supply pipeline:
the compressor aftercooler 32 is used for cooling process gas, backwater is pressurized to a set value through the booster pump 1, a water pressure gauge is arranged in a main pipeline behind the booster pump and used for monitoring the water pressure in the pipeline, when the water pressure is reduced, the booster pump is automatically pressurized to a specified pressure and plays a role in safety monitoring, when the water pressure suddenly drops due to failure of the booster pump, a quick-cut valve in the main pipeline is automatically closed, a waterway is cut off, the process gas is prevented from flowing backwards into a pipeline of a water system, the quick-cut reaction time is 2S, and the safety function is played; and a pH monitor is arranged in the main pipeline after the quick-cut valve and is used for monitoring the pH value of backwater and providing pH value data for the spraying device.
The water drum of this device is all connected through the ring flange, and this case water drum is the cylinder bucket that diameter 400mm is long 2000mm, and the water drum material is 06Cr17Ni12Mo2, 316 stainless steel promptly.
(2) The second part is a spraying device, as shown in fig. 2:
the spraying device is installed in series with a process gas circulation pipeline, as shown in the figure, the top of the main pipeline is provided with a process gas inlet, the main pipeline is divided into a first spraying pipe 17 and a second spraying pipe 18, the first spraying pipe 17 and the second spraying pipe 18 are arranged in parallel, the pipeline adopts DN400 multiplied by 10mm, the material is 06Cr17Ni12Mo2, and the lengths of the first spraying pipe and the second spraying pipe are 5000mm;
the first spray pipe and the second spray pipe are provided with a front stop valve 19 and a rear stop valve 25, and DN400 gate valves are selected for the front stop valve 19 and the rear stop valve 25 in the embodiment, because the process gas of the gas-based shaft furnace contains high-pressure harmful gas, when the high-pressure atomizing nozzle is overhauled and replaced, the process gas must be cut off firstly, and then the process gas is diffused and purged to be qualified before being replaced;
the purge pipe 21 is welded at the position 500mm away from the front stop valve on the first spray pipe and the second spray pipe, compressed air is externally connected with the purge pipe, a DN50 multiplied by 3mm seamless steel pipe is adopted as the purge pipe, the material is Q235B, and because a large amount of harmful gas is contained in the components of the process gas, when the high-pressure atomizing nozzle is overhauled and replaced, air purging is needed to be carried out, so that the residual process gas is prevented from damaging overhaulers; the purging stop valve 20 is arranged on the purging pipe, the purging stop valve is a DN50 ball valve, and when the maintenance is finished, the purging stop valve is stopped and must be completely closed to prevent the process gas from being blown out of the purging pipe;
four high-pressure atomizing nozzles 22 are arranged in the middle of the first atomizing pipe and the second atomizing pipe, the distance between the high-pressure atomizing nozzles is 500mm, the high-pressure atomizing nozzles 22 and the atomizing pipe form an included angle of 90 degrees, and the high-pressure atomizing nozzles are vertically screwed on the atomizing pipe, the high-pressure atomizing nozzles adopt conical spray heads, the material of the high-pressure atomizing nozzles is 06Cr17Ni12Mo2, namely 316 stainless steel, the aperture of the spray holes is 4mm, the spray angle of the spray heads is 110 degrees, and the shape of the sprayed water is conical, as shown in fig. 3;
the first spray pipe 17 and the second spray pipe 18 are respectively provided with a diffusing pipe 24, the diffusing pipes 24 are connected with the spray pipes through welding, DN50 multiplied by 3mm seamless steel pipes are selected as diffusing pipes in the embodiment, Q235B is selected as a material, the diffusing pipes 24 are provided with diffusing stop valves 23, DN50 ball valves are selected as diffusing stop valves in the embodiment, and because the first spray pipe and the second spray pipe contain high-pressure harmful gas, the process gas in the pipeline must be diffused firstly when the high-pressure atomizing nozzle is overhauled and replaced, and meanwhile, the purging is carried out, and overhauling and replacement work can be carried out when the purging air reaches qualification.
(3) The third part is a condensing and dehydrating device, as shown in fig. 4:
the process gas from the spraying device enters from the bottom of the cooling tower 30 and exits from the upper part of the cooling tower 30, when the process gas passes through the cooling tower 30, the moisture in the process gas is collected at the bottom of the cooling tower and is sent to the humidifier 34 for use through the water pump 33, the outlet water pH monitor 27 is arranged in the outlet water pipeline at the bottom of the tower and is used for monitoring the pH value of the outlet water at the bottom of the tower, data are provided for adjusting the water quantity of the spraying device, and the second CO is arranged in the outlet pipeline of the process gas at the upper part of the cooling tower 2 Monitor 26 for monitoring outlet CO 2 Concentration variation.
The water supply data adopted in the embodiment comprises interface size, orifice aperture, spray angle and the like, and different interface sizes, orifice aperture, spray angle and the like can be selected according to different pH values of the water supply system so as to change the water flow of the high-pressure atomizing nozzle, thereby meeting the water system adjusting requirements under different working conditions.
(4) The working principle and the operation method are as follows:
the device utilizes the backwater of the compressor aftercooler 32 to be pressurized and then sent to a spraying device, the water is atomized by the spraying device and then sprayed into a process gas pipeline, and the CO in the water is released by utilizing the low pressure and high temperature of the process gas 2 And then the water is condensed and dehydrated and sent to a humidifier, so that the acid backwater of the aftercooler of the compressor does not return to the water system, and the acid corrosion of the water system is avoided.
CO in the process gas during normal production of the example 2 The content is 5.02%, and a large amount of CO is absorbed by water in backwater of the compressor after the process gas passes through the compressor aftercooler 2 The pH value of the backwater of the aftercooler is 3.9-4.2 according to the measurement of the pH monitor, the backwater is condensed by a cooling tower to remove water after spraying, the pH value of the backwater of the cooling tower is 6.4-6.7, and the acidity of the backwater reduces the corrosion of the pipeline to the minimum.
In the normal production process, the first spray pipe and the second spray pipe are in primary and secondary relation, and spray is switched every month, so that the average service life of the high-pressure atomizing nozzles of the first spray pipe and the second spray pipe is guaranteed.
(5) The implementation effect is as follows:
the return water of the ordinary compressor post-cooler returns to the water system to lower the PH value of the water system, and a large amount of chemical agent is needed to neutralize the PH value of the water, so that the cost is increased. According to the method, the water system is used for spraying all backwater of the aftercooler of the compressor, and the pH value of the water system is not changed. The spraying device of the method is simple and easy to replace, and can be replaced on line in the normal production process without influencing the normal production.
Claims (5)
1. The utility model provides a device for adjusting gas base shaft furnace water system pH valve which characterized in that: the device comprises a gas-based shaft furnace (28), a spraying device (29), a cooling tower (30), a compressor (31), a compressor aftercooler (32) and a booster pump (1); the process gas outlet of the gas-based shaft furnace (28) is communicated with a cooling tower (30) through a process gas pipeline, a spraying device (29) is arranged on the process gas pipeline between the gas-based shaft furnace (28) and the cooling tower (30), and the spraying device (29) can spray into the process gas pipeline; the air outlet of the cooling tower (30) is communicated with the air inlet of the compressor (31), and the air outlet of the compressor (31) is communicated with an air inlet pipeline of the aftercooler (32) of the compressor; and a cooling backwater outlet of the compressor aftercooler (32) is communicated with an inlet of the spraying device (29) through a booster pump (1).
2. The device for adjusting the ph of a gas-based shaft furnace water system according to claim 1, wherein: the spraying device (29) comprises a water drum, a branch water pipe, a spraying pipe and a high-pressure atomizing nozzle (22); the spray pipes are connected in series on the process gas pipeline, at least one high-pressure atomizing nozzle (22) is arranged on the process gas pipeline, and a spray opening of the high-pressure atomizing nozzle (22) extends into the spray pipes; the branch water pipes are the same in number and are communicated with the high-pressure atomizing nozzles (22) in a one-to-one correspondence manner; the booster pump (1) is communicated with the water drum, and the other ends of the branch water pipes are communicated with the water drum.
3. The device for adjusting the ph of a gas-based shaft furnace water system according to claim 2, wherein: at least two spraying devices (29) are arranged, and each spraying device (29) is arranged in parallel.
4. The device for adjusting the ph of a gas-based shaft furnace water system according to claim 2, wherein: the spray pipe is provided with a purge pipe (21) and a purge stop valve (20) at the front end of the high-pressure atomizing nozzle (22), and a diffusing pipe (24) and a diffusing stop valve (23) at the rear end of the high-pressure atomizing nozzle (22).
5. The device for regulating the acidity and alkalinity of a gas-based shaft furnace water system according to any one of claims 1 to 4, wherein: the humidifier also comprises a water pump (33) and a humidifier (34); the water outlet of the cooling tower (30) is communicated with a humidifier (34) through a water pump (33).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202321467406.1U CN220119885U (en) | 2023-06-09 | 2023-06-09 | Device for adjusting pH value of gas-based shaft furnace water system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202321467406.1U CN220119885U (en) | 2023-06-09 | 2023-06-09 | Device for adjusting pH value of gas-based shaft furnace water system |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN220119885U true CN220119885U (en) | 2023-12-01 |
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202321467406.1U Active CN220119885U (en) | 2023-06-09 | 2023-06-09 | Device for adjusting pH value of gas-based shaft furnace water system |
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| Country | Link |
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| CN (1) | CN220119885U (en) |
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2023
- 2023-06-09 CN CN202321467406.1U patent/CN220119885U/en active Active
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