Coke oven gas waste heat recovery and reuse device

Abstract

The utility model relates to a coke oven gas waste heat recovery and reuse device, comprising a coke oven chimney, a heat pipe heat exchanger, a circulating wastewater pump, an ammonia distillation tower, a first cooler, a reflux tank, a reflux pump, a vacuum system and a residual ammonia water treatment system; the coke oven chimney is connected to the heat pipe heat exchanger and provides a heat source for it, the bottom of the ammonia distillation tower is connected to the heat exchange inlet of the heat pipe heat exchanger through a first circulation pipeline, and the heat exchange outlet of the heat pipe heat exchanger is connected to the lower part of the ammonia distillation tower through a second circulation pipeline, and the circulating wastewater pump is installed on the first circulation pipeline; the top of the ammonia distillation tower is connected to the reflux tank through a divider, the bottom of the reflux tank is connected to the upper part of the ammonia distillation tower through a reflux pump, and the top of the reflux tank is connected to the vacuum system. The utility model uses the waste heat of coke oven gas for the ammonia distillation process, realizes the recycling of energy, and improves the energy utilization efficiency.

Description

Technical Field

[0001] The utility model relates to a waste heat utilization device, in particular to a coke oven gas waste heat recovery and reuse device, belonging to the technical field of coke oven gas waste heat recovery. Background Art

[0002] Coke oven gas is an important product in the coking process, which contains a large amount of heat energy. In the traditional coke oven gas treatment method, this part of heat energy is often directly discharged, resulting in energy waste and environmental pollution. At the same time, the ammonia evaporation process in the coking wastewater treatment is a key step in wastewater treatment, and its operating cost accounts for more than 50% of the wastewater treatment cost. Therefore, the development of a device that can recycle the waste heat of coke oven gas for negative pressure ammonia evaporation is of great significance for improving energy efficiency, reducing production costs, and reducing environmental pollution. Utility Model Content

[0003] The utility model mainly aims at the above-mentioned problems existing in the prior art and provides a coke oven gas waste heat recovery and reuse device.

[0004] The purpose of this utility model is mainly achieved through the following solutions:

[0005] A coke oven gas waste heat recovery and reuse device comprises a coke oven chimney, a heat pipe heat exchanger, a circulating wastewater pump, an ammonia still, a first cooler, a reflux tank, a reflux pump, a vacuum system and a residual ammonia water treatment system; the coke oven chimney is connected to the heat pipe heat exchanger and provides a heat source for it, the bottom of the ammonia still is connected to the heat exchange inlet of the heat pipe heat exchanger through a first circulation pipeline, and the heat exchange outlet of the heat pipe heat exchanger is connected to the lower part of the ammonia still through a second circulation pipeline, and the circulating wastewater pump is installed on the first circulation pipeline; the top of the ammonia still is connected to the reflux tank through a divider, the bottom of the reflux tank is connected to the upper part of the ammonia still through a reflux pump, and the top of the reflux tank is connected to the vacuum system.

[0006] Preferably, the coke oven chimney is connected to the medium inlet of the heat pipe heat exchanger through a first heat exchange pipe, and the medium outlet of the heat pipe heat exchanger is connected to the coke oven chimney through a second heat exchange pipe.

[0007] Preferably, the fractionator is installed at the top of the ammonia distillation tower, and the outlet of the fractionator is connected to the reflux tank through a first reflux pipe, and the first cooler is installed on the first reflux pipe.

[0008] Preferably, the bottom of the reflux tank is connected to the upper part of the ammonia distillation tower through a second reflux pipe, and the reflux pump is installed on the second reflux pipe.

[0009] Preferably, after passing through the reflux pump, the second reflux pipeline is also connected to an ammonia water output pipeline.

[0010] Preferably, the vacuum system includes a vacuum pump and a second cooler, the top of the reflux tank is connected to the inlet of the vacuum pump through a first vacuum pipe, the outlet of the vacuum pump is connected to an exhaust gas recovery pipe, and the second cooler is installed on the first vacuum pipe.

[0011] Preferably, the residual ammonia water treatment system comprises a residual ammonia water tank, a residual ammonia water pump, a residual ammonia water wastewater heat exchanger, a pipeline mixer and an ammonia evaporation wastewater pump. The bottom of the ammonia evaporation tower is also connected to a wastewater discharge pipe, and an ammonia evaporation wastewater pump and a residual ammonia water wastewater heat exchanger are sequentially installed on the wastewater discharge pipe along the flow direction of the wastewater. The outlet of the residual ammonia water tank is connected to the middle part of the ammonia evaporation tower through an ammonia inlet pipe, and a residual ammonia water pump, a residual ammonia water wastewater heat exchanger and a pipeline mixer are sequentially installed on the ammonia inlet pipe along the flow direction of the ammonia water.

[0012] Preferably, one side of the pipeline mixer is connected to an alkali solution inlet.

[0013] Preferably, a filter assembly is installed on the ammonia inlet pipeline between the residual ammonia water tank and the residual ammonia water pump.

[0014] Preferably, the bottom of the ammonia distillation tower is connected to a slag discharge pipeline.

[0015] Therefore, compared with the prior art, the utility model has the following advantages:

[0016] (1) Improve energy efficiency: The waste heat of coke oven gas is used in the ammonia steaming process, which realizes the recycling of energy and improves energy efficiency;

[0017] (2) Reduce production costs: Compared with traditional ammonia evaporation processes, the negative pressure ammonia evaporation process has lower energy consumption and costs, which helps to reduce production costs:

[0018] (3) Reduce environmental pollution: By recycling the waste heat of coke oven gas, the emission of waste gas is reduced, thus reducing environmental pollution:

[0019] (4) Improving wastewater treatment efficiency: The negative pressure ammonia evaporation process can effectively control the process of ammonia nitrogen indicators and improve wastewater treatment efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a structural schematic diagram of the utility model.

[0021] Illustration: 1-coke oven chimney, 2-heat pipe heat exchanger, 3-circulating wastewater pump, 4-ammonia distillation tower, 5-first cooler, 6-reflux tank, 7-reflux pump, 8-first circulation pipeline, 9-second circulation pipeline, 10-divider, 11-first heat exchange pipeline, 12-second heat exchange pipeline, 13-first reflux pipeline, 14-second reflux pipeline, 15-ammonia output pipeline, 16-vacuum pump, 17-second cooler, 18-first vacuum pipeline, 19-tail gas recovery pipeline, 20-residual ammonia tank, 21-residual ammonia pump, 22-residual ammonia wastewater heat exchanger, 23-pipeline mixer, 24-ammonia distillation wastewater pump, 25-wastewater discharge pipeline, 26-ammonia inlet pipeline, 27-slag discharge pipeline. DETAILED DESCRIPTION

[0022] The technical solution of the utility model is further described in detail below through specific embodiments and in combination with the accompanying drawings. It should be understood that the implementation of the utility model is not limited to the following embodiments, and any form of modification and / or change made to the utility model will fall within the protection scope of the utility model.

[0023] In the present invention, unless otherwise specified, all parts and percentages are weight units, and the equipment and raw materials used can be purchased from the market or are commonly used in the field. The methods in the following embodiments, unless otherwise specified, are conventional methods in the field. The components or equipment in the following embodiments, unless otherwise specified, are universal standard parts or components known to those skilled in the art, and their structures and principles are known to those skilled in the art through technical manuals or conventional experimental methods.

[0024] Embodiment 1:

[0025] like Figure 1 As shown, the utility model provides a technical solution, a coke oven gas waste heat recovery and reuse device, which consists of a coke oven chimney 1, a heat pipe heat exchanger 2, a circulating wastewater pump 3, an ammonia distillation tower 4, a first cooler 5, a reflux tank 6, a reflux pump 7, a vacuum system and a residual ammonia water treatment system, and the high-temperature coke oven gas is introduced into the coke oven chimney 1.

[0026] The coke oven chimney 1 is connected to the heat pipe heat exchanger 2 and provides a heat source for it. The bottom of the ammonia still 4 is connected to the heat exchange inlet of the heat pipe heat exchanger 2 through the first circulation pipeline 8, and the heat exchange outlet of the heat pipe heat exchanger 2 is connected to the lower part of the ammonia still 4 through the second circulation pipeline 9. The circulating wastewater pump 3 is installed on the first circulation pipeline 8. The circulating wastewater pump 3 extracts the ammonia still 4 from the bottom of the ammonia still 4, and then flows back to the ammonia still 4 after heat exchange with the high-temperature coke oven gas through the heat pipe heat exchanger 2; the top of the ammonia still 4 is connected to the reflux tank 6 through the divider 10, the bottom of the reflux tank 6 is connected to the upper part of the ammonia still 4 through the reflux pump 7, and the top of the reflux tank 6 is connected to the vacuum system, which can ensure the operation of the ammonia still under negative pressure; the divider 10 is a prior art, and its specific structure is not within the scope of protection of the present application, and those skilled in the art can obtain it through common knowledge, conventional means or simple deduction in the art, which will not be repeated here.

[0027] The bottom of the ammonia still 4 is connected to a slag discharge pipe 27. In this embodiment, the ammonia still 4 adopts an inclined hole tray, which has the advantages of high tray efficiency, small pressure drop, and anti-clogging.

[0028] Embodiment 2:

[0029] like Figure 1 As shown, the utility model provides another technical solution, a coke oven gas waste heat recovery and reuse device, which is different from Example 1 in that the coke oven chimney 1 is connected to the medium inlet of the heat pipe heat exchanger 2 through the first heat exchange pipe 11, and the medium outlet of the heat pipe heat exchanger 2 is connected to the coke oven chimney 1 through the second heat exchange pipe 12, and the coke oven gas in the coke oven chimney 1 provides a heat source for heat exchange of ammonia vapor wastewater.

[0030] Embodiment 3:

[0031] like Figure 1 As shown, the utility model provides another technical solution, a coke oven gas waste heat recovery and reuse device, which is different from Example 1 in that the above-mentioned reducer 10 is installed on the top of the ammonia evaporation tower 4, and the outlet of the reducer 10 is connected to the reflux tank 6 through the first reflux pipe 13, the first cooler 5 is installed on the first reflux pipe 13, the bottom liquid outlet of the reflux tank 6 is connected to the upper part of the ammonia evaporation tower 4 through the second reflux pipe 14, and the reflux pump 7 is installed on the second reflux pipe 14.

[0032] Specifically, after passing through the reflux pump 7, the second reflux pipeline 14 is also connected to an ammonia water output pipeline 15 for external delivery as ammonia water product.

[0033] Embodiment 4:

[0034] like Figure 1As shown, the utility model provides another technical solution, a coke oven gas waste heat recovery and reuse device, which is different from Example 1 in that the above-mentioned vacuum system is composed of a vacuum pump 16 and a second cooler 17, and the top gas outlet of the reflux tank 6 is connected to the inlet of the vacuum pump 16 through a first vacuum pipe 18, and the outlet of the vacuum pump 16 is connected to a tail gas recovery pipe 19, and the second cooler 17 is installed on the first vacuum pipe 18. The tail gas recovery pipe 19 is connected to the gas pipeline for recovery, and part of the non-condensable gas of ammonia and water vapor after passing through the second cooler 17 is sent to the gas pipeline.

[0035] Embodiment 5:

[0036] like Figure 1 As shown, the utility model provides another technical solution, a coke oven gas waste heat recovery and reuse device, which is different from Example 1 in that the above-mentioned residual ammonia water treatment system consists of a residual ammonia water tank 20, a residual ammonia water pump 21, a residual ammonia water wastewater heat exchanger 22, a pipeline mixer 23 and an ammonia evaporation wastewater pump 24. The bottom of the ammonia evaporation tower 4 is also connected with a wastewater effluent pipe 25, and the ammonia evaporation wastewater pump 24 and the residual ammonia water wastewater heat exchanger 22 are sequentially installed on the wastewater effluent pipe 25 along the flow direction of the wastewater. The outlet of the residual ammonia water tank 20 is connected to the middle part of the ammonia evaporation tower 4 through an ammonia inlet pipe 26, and the residual ammonia water pump 21, the residual ammonia water wastewater heat exchanger 22 and the pipeline mixer 23 are sequentially installed on the ammonia inlet pipe 26 along the flow direction of the ammonia water, and the ammonia evaporation wastewater and the residual ammonia water are heat exchanged in the residual ammonia water wastewater heat exchanger 22.

[0037] Specifically, one side of the pipeline mixer 23 is connected to an alkali solution inlet, and the remaining ammonia water is fully mixed with the alkali solution in the pipeline mixer 23. The above-mentioned pipeline mixer 23 is a prior art, and its specific structure is not within the protection scope of the present application. Moreover, those skilled in the art can derive it through common knowledge, conventional means or simple deduction in the art, which will not be repeated here.

[0038] Specifically, a filter assembly is installed on the ammonia inlet pipeline 26 between the residual ammonia water tank 20 and the residual ammonia water pump 21. In the present embodiment, the filter assembly adopts a two-stage oil removal filter of an air flotation oil remover and a ceramic tube filter. The air flotation oil remover and the ceramic tube filter are prior arts. Their specific structures are not within the protection scope of the present application, and those skilled in the art can derive them through common sense, conventional means or simple deduction in the art, which will not be described in detail here. The residual ammonia water is treated with a two-stage oil removal and impurity treatment of an air flotation oil remover and a ceramic tube filter before entering the ammonia evaporation tower 4, thereby avoiding tar blockage in key equipment such as the ammonia evaporation tower 4.

[0039] The utility model provides a coke oven gas waste heat recovery and reuse device, and its process flow is as follows: the residual ammonia water is heat exchanged in the residual ammonia water wastewater heat exchanger 22, mixed with alkali liquid in the pipeline mixer 23, and then sent to the ammonia still 23 for distillation; the ammonia gas at the top of the ammonia still 23 is cooled by the decompressor 10 and the first cooler 5, and the reflux and ammonia concentration are adjusted, and the cooled ammonia water enters the reflux tank 6, and the non-condensable steam at the top of the tank is cooled by the second cooler 17 under the suction of the vacuum pump and enters the coal gas suction pipeline for recovery; the ammonia water at the bottom of the reflux tank 6 is extracted by the reflux pump 7, a part of which is sent to the top of the ammonia still 23 for reflux, and a part is sent out as the product ammonia water; the ammonia waste water at the bottom of the ammonia still 23 enters the flue gas heat pipe heat exchanger 2 for circulated heating through the circulating wastewater pump and then returns to the ammonia still 23, and the other part of the ammonia waste water is heat exchanged with the raw material residual ammonia water and cooled down and then sent to the wastewater treatment device for treatment. The wastewater treatment device is a subsequent process device, which is not within the protection scope of the present device and is not described here.

[0040] The coke oven gas waste heat recovery and reuse device provided by the utility model uses the waste heat of the coke oven gas for the ammonia distillation process, thereby realizing the recycling of energy and improving the energy utilization efficiency; the negative pressure ammonia distillation process has lower energy consumption and cost than the traditional ammonia distillation process, which helps to reduce production costs: by recycling the waste heat of the coke oven gas, the emission of waste gas is reduced and environmental pollution is reduced: the negative pressure ammonia distillation process can effectively control the process of ammonia nitrogen indicators and improve the wastewater treatment efficiency.

[0041] It should be understood that this embodiment is only used to illustrate the present invention and is not used to limit the scope of the present invention. In addition, it should be understood that after reading the content taught by the present invention, those skilled in the art can make various changes or modifications to the present invention, and these equivalent forms also fall within the scope defined by the claims attached to this application.

Claims

1. A coke oven gas waste heat recovery and reuse device, characterized in that: The invention comprises a coke oven chimney (1), a heat pipe heat exchanger (2), a circulating wastewater pump (3), an ammonia still (4), a first cooler (5), a reflux tank (6), a reflux pump (7), a vacuum system and a residual ammonia water treatment system; the coke oven chimney (1) is connected to the heat pipe heat exchanger (2) and provides a heat source therefor; the bottom of the ammonia still (4) is connected to the heat exchange inlet of the heat pipe heat exchanger (2) through a first circulating pipe (8), and the heat exchange outlet of the heat pipe heat exchanger (2) is connected to the lower part of the ammonia still (4) through a second circulating pipe (9); the circulating wastewater pump (3) is installed on the first circulating pipe (8); the top of the ammonia still (4) is connected to the reflux tank (6) through a divider (10); the bottom of the reflux tank (6) is connected to the upper part of the ammonia still (4) through a reflux pump (7); and the top of the reflux tank (6) is connected to the vacuum system.

2. The coke oven gas waste heat recovery and reuse device according to claim 1, characterized in that: The coke oven chimney (1) is connected to the medium inlet of the heat pipe heat exchanger (2) via a first heat exchange pipe (11), and the medium outlet of the heat pipe heat exchanger (2) is connected to the coke oven chimney (1) via a second heat exchange pipe (12).

3. The coke oven gas waste heat recovery and reuse device according to claim 1, characterized in that: The fractionator (10) is installed at the top of the ammonia distillation tower (4), and the outlet of the fractionator (10) is connected to the reflux tank (6) through a first reflux pipe (13), and the first cooler (5) is installed on the first reflux pipe (13).

4. The coke oven gas waste heat recovery and reuse device according to claim 3 is characterized in that: The bottom of the reflux tank (6) is connected to the upper part of the ammonia distillation tower (4) via a second reflux pipe (14), and the reflux pump (7) is installed on the second reflux pipe (14).

5. The coke oven gas waste heat recovery and reuse device according to claim 4, characterized in that: After passing through the reflux pump (7), the second reflux pipeline (14) is also connected to an ammonia water output pipeline (15).

6. The coke oven gas waste heat recovery and reuse device according to claim 1, characterized in that: The vacuum system comprises a vacuum pump (16) and a second cooler (17); the top of the reflux tank (6) is connected to the inlet of the vacuum pump (16) via a first vacuum pipe (18); the outlet of the vacuum pump (16) is connected to an exhaust gas recovery pipe (19); and the second cooler (17) is installed on the first vacuum pipe (18).

7. The coke oven gas waste heat recovery and reuse device according to claim 1, characterized in that: The residual ammonia water treatment system comprises a residual ammonia water tank (20), a residual ammonia water pump (21), a residual ammonia water wastewater heat exchanger (22), a pipeline mixer (23) and an ammonia evaporation wastewater pump (24); the bottom of the ammonia evaporation tower (4) is also connected to a wastewater discharge pipeline (25); the ammonia evaporation wastewater pump (24) and the residual ammonia water wastewater heat exchanger (22) are sequentially installed on the wastewater discharge pipeline (25) along the flow direction of the wastewater; the outlet of the residual ammonia water tank (20) is connected to the middle of the ammonia evaporation tower (4) through an ammonia inlet pipeline (26); the residual ammonia water pump (21), the residual ammonia water wastewater heat exchanger (22) and the pipeline mixer (23) are sequentially installed on the ammonia inlet pipeline (26) along the flow direction of the ammonia water.

8. The coke oven gas waste heat recovery and reuse device according to claim 7, characterized in that: One side of the pipeline mixer (23) is connected to an alkaline solution inlet.

9. The coke oven gas waste heat recovery and reuse device according to claim 8, characterized in that: A filter assembly is installed on the ammonia inlet pipeline (26) between the residual ammonia water tank (20) and the residual ammonia water pump (21).

10. The coke oven gas waste heat recovery and reuse device according to claim 1, characterized in that: The bottom of the ammonia distillation tower (4) is connected to a slag discharge pipeline (27).

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