Light oil separation device for removing oil gas from coke oven gas

Abstract

The light oil separation device comprises a shell, a coke oven gas outlet pipeline is connected to the top of the shell, a light oil drainage pipeline is connected to the bottom of the shell, and a first valve and a second valve are arranged on the coke oven gas outlet pipeline and the light oil drainage pipeline respectively; an open inner tank is arranged in the shell, the bottom of the inner tank is connected with a light oil-containing wastewater inlet pipeline, the light oil-containing wastewater inlet pipeline is provided with a vertical section, and a valve III is arranged on the light oil-containing wastewater inlet pipeline; the vertical section of the light oil-containing wastewater inlet pipeline is connected with a sewage drainage pipeline, and a valve IV is arranged on the sewage drainage pipeline; a coke oven gas inlet pipeline is inserted into the inner tank, and after wastewater containing light oil enters the inner tank and oil and water are layered, the coke oven gas inlet pipeline is inserted into a water layer below the coke oven gas inlet pipeline. The oil-water separation device performs oil-water separation on wastewater containing light oil, reduces the proportion of the light oil in the water and the oil-carrying proportion of coke oven gas, and ensures the oil removal effect of the coke oven gas.

Description

Technical Field

[0001] The utility model relates to the technical field of coke oven gas, and particularly relates to a light oil separation device for removing oil and gas from coke oven gas. Background Art

[0002] Coke oven gas is a mixture mainly composed of CO and H2, rich in various hydrocarbons, various forms of sulfur and oil dust particles. The purified coke oven gas is an important chemical raw material, which can synthesize a variety of important organic substances. At present, there are very mature and complete production processes for synthesizing methanol and urea from coke oven gas. By further deep processing of coke oven gas, purer H2 and CO can be obtained, and high-purity gases are important reaction raw materials for addition and chain extension of unsaturated hydrocarbons.

[0003] Hydrocarbons and oil dust particles are impurities with a relatively high proportion in coke oven gas. In industrial production, the larger molecular weight aromatic hydrocarbons and derivatives are removed through debenzolization and benzol scrubbing, greatly reducing the impact on subsequent production processes, but the hydrocarbons with smaller molecular weights entrained in the gas cannot be well captured. Therefore, many coking plants will add a step of oil and naphthalene removal process to reduce the impact on subsequent processes. Activated carbon is mostly used as the filler in the tower to adsorb oil dust, but to ensure the activity of the activated carbon, the activated carbon needs to be replaced regularly.

[0004] At present, the wastewater containing alcohol esters is used to remove oil from coke oven gas through a spray tower. The treated liquid phase accumulates at the bottom of the spray tower and gradually divides into three layers, which are light oil, water and heavy oil from top to bottom. The heavy oil is discharged from the heavy oil drain pipeline at the bottom of the spray tower, while the light oil and water enter the water seal tank outside the tower together. This part of the water containing light oil in the water seal tank is recycled to the spray tower through a circulation pump and sprayed down from the middle and upper parts of the spray tower to continue removing oil from coke oven gas. However, since the spray water in the tower is in a circulating state, the oil and water on the surface cannot be well stratified, resulting in a small discharge amount of the light oil on the upper layer, making it always in an enriched state. When it reaches a certain proportion, it will affect the capture effect of oil dust in coke oven gas, and due to its unique physical and chemical properties, it is inevitable that the treated coke oven gas will carry light oil into the subsequent system, resulting in an unsatisfactory treatment effect of coke oven gas. Therefore, it is urgent to further separate the oil and water from this part of the wastewater containing light oil in the spray tower to ensure the oil removal effect of coke oven gas. Content of the Utility Model

[0005] The technical problem to be solved by the utility model is to overcome the deficiencies of the prior art and provide a light oil separation device for removing oil and gas from coke oven gas, which can separate the oil and water from the wastewater containing light oil in the spray tower, thereby reducing the proportion of light oil in the water, reducing the load of subsequent water treatment, reducing the oil-carrying ratio of coke oven gas, and ensuring the oil removal treatment effect of coke oven gas.

[0006] The technical solution of the utility model is as follows:

[0007] A light oil separation device for removing oil and gas from coke oven gas includes a housing. A coke oven gas outlet pipeline is connected to the top of the housing, and a light oil drain pipeline is connected to the bottom. A valve one and a valve two are respectively arranged on the coke oven gas outlet pipeline and the light oil drain pipeline. An open inner tank is arranged inside the housing. A light oil-containing wastewater inlet pipeline is connected to the bottom of the inner tank. The light oil-containing wastewater inlet pipeline has a vertical section and a valve three is arranged on the light oil-containing wastewater inlet pipeline. The vertical section of the light oil-containing wastewater inlet pipeline is connected to a sewage drain pipeline, and a valve four is arranged on the sewage drain pipeline. A coke oven gas inlet pipeline is inserted into the inner tank. After the light oil-containing wastewater enters the inner tank and is separated into oil and water layers, the coke oven gas inlet pipeline is inserted into the lower water layer.

[0008] Preferably, a coke oven gas replacement pipeline one is connected to the bottom of the housing. The coke oven gas replacement pipeline one is respectively connected to the light oil drain pipeline and a coke oven gas replacement pipeline two. The coke oven gas replacement pipeline two is connected to the coke oven gas outlet pipeline. A valve five and a valve six are respectively arranged on the coke oven gas replacement pipeline one and the coke oven gas replacement pipeline two.

[0009] Preferably, a plurality of support rods are arranged on the outer wall of the inner tank, and the support rods are fixed on the inner wall of the housing.

[0010] Preferably, the inner tank is cylindrical.

[0011] Preferably, the sewage drain pipeline is connected to a sewage tank.

[0012] Preferably, the middle part of the housing is cylindrical, the top is conical, and the bottom is arc-shaped.

[0013] Compared with the prior art, the utility model has the following beneficial effects:

[0014] The light oil separation device for removing oil and gas from coke oven gas of the utility model, by transforming the water seal tank, provides a relatively stable buffer environment while ensuring the water seal, can better separate the light oil-containing wastewater in the spray tower, thereby reducing the proportion of light oil in the water. The separated wastewater can be recycled back to the spray tower to treat the coke oven gas, reducing the load of subsequent water treatment. The separated light oil can also reduce the oil-carrying ratio of the coke oven gas, ensuring the oil removal treatment effect of the coke oven gas, and thus reducing the impact on the subsequent processes. Description of the Drawings

[0015] Figure 1 It is a schematic diagram of using a spray tower to treat coke oven gas.

[0016] Figure 2This is a schematic structural diagram of the light oil separation device for removing oil and gas from coke oven gas in the present utility model.

[0017] In the figure, 1 is the outer shell; 2 is the coke oven gas outlet pipeline; 3 is the light oil drainage pipeline; 4 is valve one; 5 is valve two; 6 is the inner tank; 7 is the light oil-containing wastewater inlet pipeline; 701 is the vertical section; 8 is valve three; 9 is the sewage drainage pipeline; 10 is valve four; 11 is the coke oven gas inlet pipeline; 12 is the coke oven gas replacement pipeline one; 13 is the coke oven gas replacement pipeline two; 14 is valve five; 15 is valve six; 16 is the support rod; 17 is the sewage tank; 18 is the spray tower; 19 is the residual liquid tank; 20 is the cleaning pump; 21 is the heavy oil drainage pipeline; 22 is the circulation pump. Detailed implementation mode

[0018] In order to enable those skilled in the art to better understand the technical solutions in the present utility model, the technical solutions of the present utility model will be clearly and completely described below in conjunction with the embodiments of the present utility model.

[0019] Embodiment 1

[0020] As Figure 2 shown, this embodiment provides a light oil separation device for removing oil and gas from coke oven gas, including an outer shell 1. The central main part of the outer shell 1 is cylindrical, the top is conical, and the bottom is arc-shaped. An open cylindrical inner tank 6 is arranged inside the outer shell 1. A plurality of support rods 16 are arranged on the outer wall of the inner tank 6, and the support rods 16 are fixed on the inner wall of the outer shell 1; the bottom of the inner tank 6 is connected with a light oil-containing wastewater inlet pipeline 7. The light oil-containing wastewater inlet pipeline 7 is provided with a vertical section 701 and a valve three 8 is arranged on the light oil-containing wastewater inlet pipeline 7; the vertical section 701 of the light oil-containing wastewater inlet pipeline 7 is connected with a sewage drainage pipeline 9. A valve four 10 is arranged on the sewage drainage pipeline 9, and the sewage drainage pipeline 9 is connected with a sewage tank 17.

[0021] As Figure 2 shown, the coke oven gas outlet pipeline 2 is connected to the center of the top of the outer shell 1, and the light oil drainage pipeline 3 is connected to the bottom. A valve one 4 and a valve two 5 are respectively arranged on the coke oven gas outlet pipeline 2 and the light oil drainage pipeline 3; a coke oven gas inlet pipeline 11 is inserted into the inner tank 6. After the light oil-containing wastewater enters the inner tank 6 and the oil and water are stratified, the coke oven gas inlet pipeline 11 is inserted into the lower water layer.

[0022] As Figure 1As shown in the figure, when the oil removal treatment is carried out on the coke oven gas using the spray tower 18, the coke oven gas enters from the bottom of the spray tower 18, and the wastewater containing alcohol esters stored in the residual liquid tank 19 enters the upper part of the spray tower 18 through the cleaning pump 20 and is sprayed downward to contact the upward flowing coke oven gas, removing the oil dust therein and entering the bottom of the spray tower 18. This part of the wastewater containing oil dust gradually divides into three layers, which are light oil, water, and heavy oil from top to bottom. The heavy oil is discharged through the heavy oil drainage pipeline 21 at the bottom of the spray tower 18, while the light oil and water enter the light oil separation device outside the tower in this embodiment. After further oil-water separation treatment, the separated water is recycled to the spray tower 18 through the circulation pump 22 and sprayed downward from the middle and upper parts of the spray tower 18 to continue the oil removal treatment of the coke oven gas.

[0023] When treating the light oil-containing wastewater using the device of this embodiment, open the valve three 8. After the light oil-containing wastewater enters the inner tank 6, close the valve three 8, open the other three valves, and introduce coke oven gas into the inner tank 6. After the light oil-containing wastewater stands in the inner tank 6 for a period of time, it gradually stratifies due to the density difference between oil and water. Assume that the liquid level height of the upper oil layer is h1 and the density is ρ1; the liquid level height of the lower water layer is h2 (ignoring the height of the light oil-containing wastewater inlet pipeline 7 at the bottom of the inner tank 6), and the density is ρ2; the liquid level height of the water column in the vertical section 701 is h3 (ignoring the height of the light oil-containing wastewater inlet pipeline 7 at the bottom of the inner tank 6), and the density is ρ2; the pressure of the coke oven gas is P. Then when ρ1gh1 + ρ2gh2 + P > ρ2gh3, the wastewater with a relatively large density remains at the bottom of the inner tank 6 and enters the sewage tank 17 through the pressure difference; when ρ1gh1 + ρ2gh2 + P < ρ2gh3, the lighter light oil remains in the upper part of the inner tank 6. After reaching a certain height, it enters the inner space of the outer shell 1 through overflow, and finally the light oil is discharged by adjusting the opening degree of the control valve two.

[0024] In this embodiment, by transforming the water seal tank, while ensuring the water seal, a relatively stable buffer environment is provided, which can better separate the light oil-containing wastewater in the spray tower 18, thereby reducing the proportion of light oil in the water. The separated wastewater can be recycled back to the spray tower 18 to treat the coke oven gas, reducing the load of subsequent water treatment. The separated light oil can also reduce the oil-carrying ratio of the coke oven gas, thereby reducing the impact on subsequent processes.

[0025] Embodiment 2

[0026] On the basis of Embodiment 1, as Figure 2As shown in the figure, a first coke oven gas replacement pipeline 12 is connected to the bottom of the outer shell 1. The first coke oven gas replacement pipeline 12 is respectively connected to the light oil drainage pipeline 3 and the second coke oven gas replacement pipeline 13. The second coke oven gas replacement pipeline 13 is connected to the coke oven gas outlet pipeline 2. A fifth valve 14 and a sixth valve 15 are respectively arranged on the first coke oven gas replacement pipeline 12 and the second coke oven gas replacement pipeline 13.

[0027] When the device of this embodiment is started up, first close the first valve 4 to the fourth valve 10, open the fifth valve 14 and the sixth valve 15, introduce coke oven gas into the inner tank 6, so that the air in the outer shell 1 is discharged through the first coke oven gas replacement pipeline 12 and the second coke oven gas replacement pipeline 13, and the replacement of coke oven gas is completed, which can play a role in ensuring the stable and safe operation during startup. Subsequently, close the sixth valve 15, and then the treatment of light oil-containing wastewater can be started.

Claims

1. A light oil separation device for removing oil and gas from coke oven gas, characterized in that, It includes a housing (1). A coke oven gas outlet pipeline (2) is connected to the top of the housing (1), and a light oil drainage pipeline (3) is connected to the bottom. A valve one (4) and a valve two (5) are respectively arranged on the coke oven gas outlet pipeline (2) and the light oil drainage pipeline (3); An open inner tank (6) is arranged inside the housing (1). A light oil-containing wastewater inlet pipeline (7) is connected to the bottom of the inner tank (6). The light oil-containing wastewater inlet pipeline (7) has a vertical section (701) and a valve three (8) is arranged on the light oil-containing wastewater inlet pipeline (7); The vertical section (701) of the light oil-containing wastewater inlet pipeline (7) is connected to a sewage drainage pipeline (9), and a valve four (10) is arranged on the sewage drainage pipeline (9); A coke oven gas inlet pipeline (11) is inserted into the inner tank (6). After the light oil-containing wastewater enters the inner tank (6) and the oil and water are separated into layers, the coke oven gas inlet pipeline (11) is inserted into the lower water layer.

2. The light oil separation device for removing oil and gas from coke oven gas according to claim 1, characterized in that, A coke oven gas replacement pipeline one (12) is connected to the bottom of the housing (1). The coke oven gas replacement pipeline one (12) is respectively connected to the light oil drainage pipeline (3) and a coke oven gas replacement pipeline two (13). The coke oven gas replacement pipeline two (13) is connected to the coke oven gas outlet pipeline (2). A valve five (14) and a valve six (15) are respectively arranged on the coke oven gas replacement pipeline one (12) and the coke oven gas replacement pipeline two (13).

3. The light oil separation device for removing oil and gas from coke oven gas according to claim 1, wherein A number of support rods (16) are arranged on the outer wall of the inner tank (6), and the support rods (16) are fixed on the inner wall of the housing (1).

4. The light oil separation device for removing oil and gas from coke oven gas according to claim 1, characterized in that, The inner tank (6) is cylindrical.

5. The light oil separation device for removing oil and gas from coke oven gas according to claim 1, characterized in that, The sewage drainage pipeline (9) is connected to a sewage tank (17).

6. The light oil separation device for removing oil and gas from coke oven gas according to claim 1, characterized in that The middle part of the housing (1) is cylindrical, the top is conical, and the bottom is arc-shaped.

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