Cooling type water bath naphthalene removal device

Abstract

The utility model discloses a cooling type water bath naphthalene removal device, which belongs to the technical field of naphthalene removal devices and comprises a naphthalene removal unit, the naphthalene removal unit consists of a plurality of naphthalene removal towers, and the top and the bottom of each naphthalene removal tower are respectively connected with a gas tower inlet pipeline and a gas tower outlet pipeline; the naphthalene removal tower comprises a shell pass and a tube pass, an inlet and an outlet of the shell pass are connected with circulating water for controlling the temperature in the tower, and the tube pass is filled with a naphthalene removal agent; according to the naphthalene removal device for the coal gas, low-content coal gas can be effectively removed, the phenomenon that naphthalene is accumulated in a hydrogen compressor and a PSA (Pressure Swing Adsorption) process when the low-content coal gas escapes to a subsequent process is prevented, and the naphthalene removal efficiency is improved. Further, pipeline elbows, heat exchangers and the like are blocked.

Description

TECHNICAL FIELD

[0001] The utility model belongs to coke oven coal comprehensive utilization field relates to a cooling type water bath naphthalene removal device. BACKGROUND

[0002] Naphthalene, the simplest condensed ring compound, is a bright flaky crystal with a special smell, volatile, sublimable, flammable and insoluble in water, and prone to substitution and hydrogenation reactions, often enters pipelines and equipment in gaseous form during coke production.

[0003] The methanol production process from coke oven gas contains a pure oxygen high-temperature conversion process. After the high-temperature combustion and conversion of tar, benzene, naphthalene and other macromolecular substances, the process gas is basically free of tar, benzene, naphthalene and other macromolecular substances. If the flow rate of the coal gas is slowed down or the temperature is lowered during subsequent coal gas purification, naphthalene in the coal gas will precipitate and deposit in the coal gas pipeline and purification equipment, thereby blocking the pipeline bends and heat exchangers. Therefore, the coal gas must be naphthalene-removed, but low-content naphthalene is difficult to remove. When a small amount of naphthalene escapes to the subsequent process, it will also cause naphthalene accumulation in the hydrogen compressor and PSA process.

[0004] Due to the production characteristics in summer, the inlet temperature of the filter will exceed the optimal naphthalene removal temperature range of the naphthalene removal agent. Therefore, measures should be taken to reduce the process gas temperature. Adding a heat exchanger before the filter can achieve this, but factors such as gas bias flow and naphthalene blocking the heat exchanger should also be considered. SUMMARY

[0005] The utility model discloses a cooling type water bath naphthalene removal device, which is used to solve the problem of low-content naphthalene removal in the prior art. When naphthalene escapes to the subsequent process, it will also cause naphthalene accumulation in the hydrogen compressor and PSA process, thereby blocking the pipeline bends and heat exchangers.

[0006] The utility model discloses a cooling type water bath naphthalene removal device, which is used to solve the problem of low-content naphthalene removal in the prior art. When naphthalene escapes to the subsequent process, it will also cause naphthalene accumulation in the hydrogen compressor and PSA process, thereby blocking the pipeline bends and heat exchangers.

[0007] Further, pressure gauges are arranged on the coal gas inlet pipeline and the blowdown pipeline, respectively. The pressure difference between the two pressure gauges is used to determine whether the naphthalene removal tower is saturated.

[0008] Further, a soft water inlet pipeline and a blowdown pipeline are also connected to the coal gas outlet pipeline.

[0009] Further, the temperature range of the circulating water is the optimal temperature range for naphthalene removal.

[0010] Further, the de-naphthalene tower is two.

[0011] Further, the plurality of de-naphthalene towers are connected in parallel.

[0012] Further, the steam in the steam line is low pressure steam, and the steam line is arranged at the bottom of the de-naphthalene tower.

[0013] The beneficial effect of the de-naphthalene tower is that the de-naphthalene tower is similar to a shell-and-tube heat exchanger, the shell side enters cooling water to cool the de-naphthalene agent in the tube side, the low temperature is beneficial to remove naphthalene in the coal gas, the naphthalene is adsorbed in the de-naphthalene agent to be removed in a concentrated manner, and other heat exchange equipment in the same temperature interval is prevented from being blocked; when the adsorbent is saturated and is switched to another de-naphthalene tower, the saturated tower is steamed at this time, the naphthalene adsorbed in the de-naphthalene agent is removed, the de-naphthalene temperature of the de-naphthalene agent is reduced by the de-naphthalene tower, and the waste of the effective adsorption space of the catalyst caused by the "partial flow" of the gas in the large tank state is avoided. The phenomenon that the conventional adsorbent regeneration tank is not regenerated completely is also avoided; the regeneration operation is simple, the regeneration is heated by low pressure steam, and the operation cost is low. BRIEF DESCRIPTION OF DRAWINGS

[0014] Figure 1 is a structure schematic view of a cooling type water bath de-naphthalene device according to an embodiment of the present application;

[0015] In the figure: 1, a coal gas inlet de-naphthalene tower pipeline; 2, a coal gas outlet de-naphthalene tower pipeline; 3, a circulating water up water pipeline; 4, a circulating water back water pipeline; 5, a low pressure steam pipeline; 6, a soft water inlet pipeline; 7, an inlet pressure gauge PI-1001; 8, an outlet pressure gauge PI-1002; 9, an inlet and outlet differential pressure gauge PID-1001; 10, a cooling type water bath de-naphthalene tower; 11, a sewage outlet pipeline. DETAILED DESCRIPTION

[0016] The present application will be described in detail below in conjunction with the drawings and specific embodiments, but this should not be understood as limiting the scope of the above-mentioned subject matter of the present application to the following embodiments, and it should be understood that these embodiments are only used to illustrate the present application and are not used to limit the scope of the present application. After reading the content taught by the present application, those skilled in the art can make various changes or modifications to the present application, and these equivalent forms also fall within the scope defined by the claims attached to the present application.

[0017] An embodiment of a cooling type water bath de-naphthalene device of the present application is as follows: Figure 1As shown, the device of the embodiment includes a de-naphthalene unit, which is composed of two cooling water bath de-naphthalene towers 10. In other embodiments, three, four or the like can also be used. When the amount of coal gas is large, the size of the cooling water bath de-naphthalene tower 10 can be adjusted according to the actual situation. Whether two, three or four de-naphthalene towers are connected in parallel. The cooling water bath de-naphthalene tower 10 is similar to a tube-shell heat exchanger. The top of the de-naphthalene tower 10 is connected to the coal gas inlet tower pipeline 1, and the bottom is connected to the coal gas outlet tower pipeline 2. The de-naphthalene tower 10 includes a shell side and a tube side. The tube side is filled with high-efficiency de-naphthalene agent, and the shell side is cooled by circulating water. The circulating water inlet pipeline 3 is connected to the inlet of the shell side, and the outlet of the shell side is connected to the circulating water return pipeline 4, completing the circulation of the cooling water in the shell side.

[0018] The circulating water inlet pipeline 3 and the circulating water return pipeline 4 are both provided with corresponding valves. When the cooling water circulation is not needed, the valves can be controlled.

[0019] Another inlet of the shell side is connected to the low-pressure steam pipeline 5. The bottom of the de-naphthalene tower is also connected to the soft water inlet pipeline 6 and the blowdown pipeline 11. In this embodiment, as shown, the blowdown pipeline 11 is connected to the soft water inlet pipeline 6, and the soft water inlet pipeline 6 is connected to the coal gas outlet de-naphthalene tower pipeline 2. Valves are provided on each pipeline for control. Figure 1

[0020] The steam in the steam pipeline is low-pressure steam, and the low-pressure steam pipeline 5 is arranged at the bottom of the de-naphthalene tower.

[0021] Pressure gauges are arranged on the coal gas inlet and outlet pipelines of the de-naphthalene tower 10. The inlet and outlet pressures are also provided with a differential pressure gauge, which is used to determine whether the de-naphthalene tower is saturated. When the differential pressure of the de-naphthalene tower reaches a certain pressure, it means that the de-naphthalene tower has been saturated, and the other tower is switched to run.

[0022] The cooling water bath de-naphthalene device of the embodiment has a simple structure and is easy to manufacture. It can be used for low-temperature and high-pressure de-naphthalene, and can maximize the efficiency of the de-naphthalene agent. The bottom is equipped with a steam pipeline, which is easy to heat wash and regenerate. It avoids clogging other heat exchange equipment.

[0023] The main process flow of the embodiment is as follows:

[0024] In this embodiment, the naphthalene-containing coal gas enters the cooling water bath de-naphthalene tower 10 through the coal gas inlet de-naphthalene tower pipeline 1. One of the cooling water bath de-naphthalene towers 10 adsorbs naphthalene in the coal gas. When the inlet and outlet differential pressure gauge PID-1001 of the cooling water bath de-naphthalene tower reaches a certain value, the other tower is switched to adsorb. The "rich naphthalene" tower is connected to the steam for heat washing. After heat washing, it is replaced by a substitute. In this embodiment, two de-naphthalene towers are used, one for adsorption and the other for replacement.

[0025] ​Specifically, when the naphthalene-containing coal gas enters the cooling water bath naphthalene removal tower 10 through the coal gas inlet naphthalene removal tower pipeline 1, the valves on the circulating water inlet pipeline 3 and the circulating water return pipeline 4 are opened. At this time, the cooling water circulates into the shell side to cool the naphthalene adsorbent in the tube side. The cooling temperature range of the circulating water is exactly in the optimal temperature range for naphthalene removal.

[0026] It should be noted that low temperature is conducive to the removal of naphthalene in coal gas and the adsorption of naphthalene in the naphthalene removal agent in the tube side. Therefore, in order to better concentrate the removal of naphthalene, the present embodiment uses circulating water cooling to prevent the subsequent naphthalene from easily blocking other heat exchange equipment in the same temperature range.

[0027] After the naphthalene removal, the coal gas is finally output through the naphthalene removal tower outlet pipeline 2.

[0028] Compared with the conventional adsorption tower, the naphthalene removal tower in the present embodiment reduces the loss of effective adsorption space of the adsorbent caused by gas deflection.

[0029] When the pressure difference monitored by the inlet and outlet pressure difference table is greater than a certain threshold value, i.e. when the adsorbed naphthalene removal tower is saturated, the valves connected to the naphthalene removal tower with high pressure monitored by the pressure table are closed, including the valves on the coal gas inlet naphthalene removal tower pipeline 1, the naphthalene removal tower outlet pipeline 2, the circulating water inlet pipeline 3, and the circulating water return pipeline 4. The related valves connected to the naphthalene removal tower for replacement are opened, including the coal gas inlet and outlet pipelines, the circulating water inlet and return pipelines, and the steam pipeline is closed.

[0030] In the present embodiment, after closing the valves connected to the naphthalene removal tower with high pressure monitored by the pressure table, the saturated naphthalene removal tower is regenerated. The regeneration process of the saturated naphthalene removal tower is as follows:

[0031] The valve on the soft water inlet pipeline 6 is opened, and the soft water enters the saturated naphthalene removal tower. Then the valve on the low-pressure steam pipeline 5 is opened, and the low-pressure steam enters the shell side of the naphthalene removal tower to heat the soft water in the shell side and perform hot washing of the naphthalene removal tower. The naphthalene removal agent in the tube side can be regenerated multiple times. In the present embodiment, the naphthalene removal agent is regenerated by using a water bath tower, which is thorough and simple to operate. The low-pressure steam is used for heating and regeneration, which has low operating cost.

Claims

1. A naphthalene removal device by cooling water bath, comprising a naphthalene removal unit, characterized in that, The denaphthalene unit is composed of multiple denaphthalene towers, the top and bottom of the denaphthalene tower are connected with a coal gas inlet tower pipeline and a coal gas outlet tower pipeline respectively; the denaphthalene tower comprises a shell pass and a tube pass, the inlet and outlet of the shell pass are connected with circulating water for controlling the temperature in the tower, the tube pass is filled with a denaphthalene agent; another inlet of the shell pass is further connected with a steam pipeline, a soft water inlet pipeline and a blowdown pipeline are further connected at the bottom of the denaphthalene tower, and a valve is arranged on each pipeline.

2. The naphthalene removal device according to claim 1, wherein A pressure table is arranged on the coal gas inlet and outlet pipeline of the denaphthalene tower respectively, a differential pressure table is further arranged on the inlet and outlet pressure, and the differential pressure table is used for judging whether the denaphthalene tower is saturated.

3. The naphthalene removal device according to claim 1, wherein The top of the denaphthalene tower is connected with a coal gas inlet tower pipeline; the bottom of the denaphthalene tower is connected with a coal gas outlet tower pipeline.

4. The naphthalene removal device according to claim 3, wherein The soft water inlet pipeline and the blowdown pipeline are connected to the coal gas outlet tower pipeline.

5. The naphthalene removal apparatus according to claim 1, wherein The temperature range of the circulating water is the optimal temperature range for naphthalene removal.

6. The naphthalene removal apparatus according to claim 1, wherein The denaphthalene tower is two.

7. The naphthalene removal apparatus according to claim 1, wherein The multiple denaphthalene towers are connected in parallel.

8. The naphthalene removal apparatus according to claim 1, wherein The steam in the steam pipeline is low-pressure steam, and the steam pipeline is arranged at the bottom of the denaphthalene tower.

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