Regeneration system of deoiling and denaphthalene tower in coke oven gas to LNG process
By using nitrogen-rich gas as a regeneration gas source in the coke oven gas to LNG process, combined with the oil and naphthalene removal tower and related equipment, the problems of nitrogen consumption and coke oven gas waste during the regeneration process of the oil and naphthalene removal tower were solved, achieving the effects of waste gas reuse and energy conservation and environmental protection.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- HANDAN IRON & STEEL GROUP CO LTD
- Filing Date
- 2025-06-19
- Publication Date
- 2026-07-03
AI Technical Summary
In the coke oven gas to LNG technology, the existing deoiling and denaphthalene removal tower regeneration process has the problem of additional nitrogen consumption or waste of coke oven gas. It is necessary to design a regeneration system that can achieve waste gas reuse without increasing the consumption of media.
Using nitrogen-rich gas from coke oven gas to LNG production as the regeneration gas source, the activated carbon is cold-blown and regenerated through a combination of an oil and naphthalene removal tower, a regeneration gas cooler, a regeneration gas electric heater, and a regeneration gas steam heater, thus avoiding the use of an external gas source.
It enables the reuse of waste gas, avoids the consumption of additional media, and features energy saving and environmental protection. It also has a simple structure and good treatment effect.
Smart Images
Figure CN224450602U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of petrochemical technology, and in particular to a regeneration system for an oil and naphthalene removal tower in a coke oven gas to LNG process. Background Technology
[0002] In the field of coke oven gas to LNG technology, there are many gas sources to choose from when regenerating the deoiling and denaphthalene-removing tower. Nitrogen can be used as a gas source for regeneration, but this results in additional nitrogen consumption. Purified coke oven gas can also be used, but this wastes the gas, which could otherwise be used to produce LNG. Therefore, it is crucial to design a regeneration system that avoids additional media consumption and allows for waste gas reuse during the regeneration process. Utility Model Content
[0003] The technical problem to be solved by this utility model is to provide a regeneration system for the deoiling and denaphthalene removal tower in the coke oven gas to LNG process that enables the reuse of waste gas.
[0004] To solve the above-mentioned technical problems, the technical solution adopted by this utility model is as follows: It includes an oil and naphthalene removal tower, a regulating valve, a regenerated gas cooler, a regenerated gas-liquid separator, a regenerated gas electric heater, and a regenerated gas steam heater; the oil and naphthalene removal tower is provided with a bottom gas inlet and a top gas inlet; the bottom gas inlet of the oil and naphthalene removal tower is connected to a regenerated gas source through a pipeline and a regulating valve; the bottom gas inlet of the oil and naphthalene removal tower is also connected to the regenerated gas electric heater and the regenerated gas steam heater in sequence through a pipeline and a regulating valve; the outlet of the regenerated gas steam heater is connected to the top gas inlet of the oil and naphthalene removal tower through a pipeline and a regulating valve; the top gas inlet of the oil and naphthalene removal tower is also connected to the regenerated gas cooler and the regenerated gas-liquid separator in sequence through a pipeline and a regulating valve.
[0005] Furthermore, the oil and naphthalene removal tower is provided in three parts; the bottom gas ports of the three oil and naphthalene removal towers are all connected to the regeneration gas source through pipelines and regulating valves, and the bottom gas ports are all connected to the regeneration gas electric heater and the regeneration gas steam heater in sequence through pipelines and regulating valves, and the top gas ports are all connected to the regeneration gas cooler and the regeneration gas gas-liquid separator in sequence through pipelines and regulating valves.
[0006] Furthermore, the bottom gas inlet of the oil and naphthalene removal tower is also connected to the coarse desulfurization tower via pipelines and regulating valves.
[0007] Furthermore, the top gas inlet of the oil and naphthalene removal tower is also connected to a venting flare via pipelines and regulating valves.
[0008] Furthermore, the regenerated gas source is also connected to the pipeline between the regenerated gas steam heater and the top gas port of the oil and naphthalene removal tower via pipelines and regulating valves.
[0009] Furthermore, the regenerated gas source is a nitrogen-rich self-cooling box used in the LNG production process from coke oven gas.
[0010] The beneficial effects of adopting the above technical solution are as follows: This utility model uses a steam heater, an electric heater, and a heat exchanger to heat and cool the regeneration gas, thereby cold blowing and regenerating the activated carbon saturated with tar and naphthalene adsorption, eliminating the need for an external gas source (such as nitrogen) for cold blowing and regeneration. In particular, using nitrogen-rich gas produced in the LNG production process from coke oven gas as the regeneration gas not only avoids additional media consumption but also achieves waste gas reuse. This utility model has a simple structure, good treatment effect, and is energy-saving and environmentally friendly. Attached Figure Description
[0011] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.
[0012] Figure 1 This is a schematic diagram of the structure of this utility model.
[0013] In the diagram: No. 1 oil and naphthalene removal tower 1; No. 2 oil and naphthalene removal tower 2; No. 3 oil and naphthalene removal tower 3; regeneration gas cooler 4; regeneration gas gas-liquid separator 5; regeneration gas electric heater 6; regeneration gas steam heater 7; regulating valves 11-18; regulating valves 21-28; regulating valves 31-38; regulating valve 09; regulating valve 51; regulating valve 52. Detailed Implementation
[0014] Figure 1As shown, the oil and naphthalene removal tower regeneration system in this coke oven gas to LNG process includes an oil and naphthalene removal tower, a regulating valve, a regeneration gas cooler 4, a regeneration gas-liquid separator 5, a regeneration gas electric heater 6, and a regeneration gas steam heater 7. The oil and naphthalene removal tower has a bottom gas inlet and a top gas inlet; there are three oil and naphthalene removal towers, namely, No. 1 oil and naphthalene removal tower 1, No. 2 oil and naphthalene removal tower 2, and No. 3 oil and naphthalene removal tower 3; the three oil and naphthalene removal towers are arranged in parallel. The bottom gas inlets of the oil and naphthalene removal towers are all connected to the regeneration gas source through pipelines and regulating valves. The regeneration gas source is the nitrogen-rich gas self-cooling box in the coke oven gas to LNG production process, and the regeneration gas is the nitrogen-rich gas generated in the coke oven gas to LNG production process. Specifically, the bottom gas inlet of the No. 1 oil and naphthalene removal tower 1 is connected to the regeneration gas source through pipelines and regulating valve 14, the bottom gas inlet of the No. 2 oil and naphthalene removal tower 2 is connected to the regeneration gas source through pipelines and regulating valve 24, and the bottom gas inlet of the No. 3 oil and naphthalene removal tower 3 is connected to the regeneration gas source through pipelines and regulating valve 34. The bottom gas inlet of the oil and naphthalene removal tower is connected to the regeneration gas electric heater 6 and the regeneration gas steam heater 7 in sequence through pipelines and regulating valves. Specifically, the bottom gas inlet of the first oil and naphthalene removal tower 1 is connected to the regeneration gas electric heater 6 and the regeneration gas steam heater 7 in sequence through pipelines and regulating valve 16; the bottom gas inlet of the second oil and naphthalene removal tower 2 is connected to the regeneration gas electric heater 6 and the regeneration gas steam heater 7 in sequence through pipelines and regulating valve 26; and the bottom gas inlet of the third oil and naphthalene removal tower 3 is connected to the regeneration gas electric heater 6 and the regeneration gas steam heater 7 in sequence through pipelines and regulating valve 36. The outlet of the regenerated gas steam heater 7 is connected to the top gas port of the oil and naphthalene removal tower through a pipeline and a regulating valve. Specifically, the outlet of the regenerated gas steam heater 7 is connected to the top gas port of the first oil and naphthalene removal tower 1 through a pipeline and a regulating valve 15, the outlet of the regenerated gas steam heater 7 is connected to the top gas port of the second oil and naphthalene removal tower 2 through a pipeline and a regulating valve 25, and the outlet of the regenerated gas steam heater 7 is connected to the top gas port of the third oil and naphthalene removal tower 3 through a pipeline and a regulating valve 35. The top gas inlet of the oil and naphthalene removal tower is connected to the regeneration gas cooler 4 and the regeneration gas-liquid separator 5 sequentially via pipelines and regulating valves. Specifically, the top gas inlet of the first oil and naphthalene removal tower 1 is connected to the regeneration gas cooler 4 and the regeneration gas-liquid separator 5 sequentially via pipelines and regulating valve 17; the top gas inlet of the second oil and naphthalene removal tower 2 is connected to the regeneration gas cooler 4 and the regeneration gas-liquid separator 5 sequentially via pipelines and regulating valve 27; and the top gas inlet of the third oil and naphthalene removal tower 3 is connected to the regeneration gas cooler 4 and the regeneration gas-liquid separator 5 sequentially via pipelines and regulating valve 37. The nitrogen-rich gas outlet of the regeneration gas-liquid separator 5 is connected to the coking process via pipelines and regulating valve 51, and the wastewater outlet is connected to the wastewater treatment center via pipelines and regulating valve 52.
[0015] Figure 1As shown, in this coke oven gas to LNG process, the regeneration system of the de-oiling and denaphthalene removal towers has the top gas inlet of the de-oiling and denaphthalene removal towers connected to the feed gas compressor via pipelines and regulating valves, which provides coke oven gas. The regulating valves include control valves and regulating valves connected in parallel with the control valves. Specifically, the top gas inlet of the first de-oiling and denaphthalene removal tower 1 is connected to the feed gas compressor via pipelines and regulating valves 11 and 12; the top gas inlet of the second de-oiling and denaphthalene removal tower 2 is connected to the feed gas compressor via pipelines and regulating valves 21 and 22; and the top gas inlet of the third de-oiling and denaphthalene removal tower 3 is connected to the feed gas compressor via pipelines and regulating valves 31 and 32. Regulating valves 11, 21, and 31 are all control valves, while regulating valves 12, 22, and 32 are all pressure equalization valves.
[0016] Figure 1 As shown, in the coke oven gas to LNG process, the regeneration system of the deoiling and denaphthalene towers is described. The bottom gas inlet of the deoiling and denaphthalene towers is also connected to the coarse desulfurization tower through pipelines and regulating valves. Specifically, the bottom gas inlet of the No. 1 deoiling and denaphthalene tower 1 is connected to the coarse desulfurization tower through pipelines and regulating valve 13; the bottom gas inlet of the No. 2 deoiling and denaphthalene tower 2 is connected to the coarse desulfurization tower through pipelines and regulating valve 23; and the bottom gas inlet of the No. 3 deoiling and denaphthalene tower 3 is connected to the coarse desulfurization tower through pipelines and regulating valve 33.
[0017] Figure 1 As shown, in the coke oven gas to LNG process, the regeneration system of the de-oiling and denaphthalene towers is described. The top gas inlet of the de-oiling and denaphthalene towers is also connected to a venting flare via pipelines and regulating valves. Specifically, the top gas inlet of the No. 1 de-oiling and denaphthalene tower 1 is connected to a venting flare via pipelines and regulating valve 18; the top gas inlet of the No. 2 de-oiling and denaphthalene tower 2 is connected to a venting flare via pipelines and regulating valve 28; and the top gas inlet of the No. 3 de-oiling and denaphthalene tower 3 is connected to a venting flare via pipelines and regulating valve 38.
[0018] Figure 1 As shown, in the coke oven gas to LNG process, the regeneration system of the deoiling and denaphthalene removal tower is connected to the pipeline between the regeneration gas steam heater 7 and the top gas port of the deoiling and denaphthalene removal tower through a pipeline and regulating valve 09.
[0019] Figure 1 As shown, the regeneration system of the de-oiling and de-naphthalene towers in this coke oven gas to LNG process, taking the No. 1 de-oiling and de-naphthalene tower 1 for cold blowing, the No. 2 de-oiling and de-naphthalene tower 2 for adsorption, and the No. 3 de-oiling and de-naphthalene tower 3 for regeneration as an example, the regeneration process is as follows:
[0020] S1: Raw material gas adsorption process: Coke oven gas from the raw material gas compressor is pressurized to 0.45MPa and enters the No. 2 deoiling and denaphthalene removal tower 2, which is in a purification state, from top to bottom through the programmable control valve 01B. Under the selective adsorption of the adsorbent, the tar and naphthalene in it are adsorbed and enter the coarse desulfurization tower through the regulating valve 23.
[0021] S2: Raw material gas depressurization process: After the adsorption of the oil and naphthalene removal tower is completed, open the programmable valve 08B on the depressurization pipeline to depressurize the No. 2 oil and naphthalene removal tower 2, so as to ensure that the regeneration gas (i.e. nitrogen-rich gas) can smoothly enter the No. 2 oil and naphthalene removal tower 2 to regenerate the bed in the subsequent process.
[0022] S3: Regeneration process of the deoiling and denaphthalene tower: After the depressurization process is completed, open the programmable valve 06C on the hot regeneration pipeline. The hot regeneration gas, i.e. nitrogen-rich gas, enters the No. 3 deoiling and denaphthalene tower 3 and purges the adsorption bed in the reverse direction, so that the outlet temperature rises to about 180°C. The adsorbed tar and naphthalene are completely desorbed, and the adsorption of the No. 3 deoiling and denaphthalene tower 3 is regenerated.
[0023] S4: Cold blowing process: After the regeneration process is completed, close the programmable valve 06C on the regeneration pipeline and open the programmable valve 04A on the cold blowing pipeline. The regeneration gas enters the No. 1 deoiling and denaphthalene removal tower 1, which is in the cold blowing process, and purges the adsorption bed in the reverse direction to reduce the bed temperature to 40°C. The cold blowing process ends.
[0024] S5: Cold blowing and pressure relief process: After the regeneration process is completed, open the programmable valve 08A on the pressure relief pipeline to fully release the regeneration gas remaining in the tower during the cold blowing process.
[0025] S6: Pressure replenishment process: After the pressure relief process is completed, most of the internal cooling gas in the No. 1 deoiling and denaphthalene removal tower 1 is discharged from the system. At this time, the raw material gas pressure replenishment valve 02A is opened to replenish the pressure of the No. 1 deoiling and denaphthalene removal tower 1. The pressure replenishment is stopped when the pressure difference with the raw material gas is less than 0.05MPa.
[0026] S7: Pressure equalization process: After the pressure replenishment program is completed, 01A and 03A are opened simultaneously to open the adsorption process and stabilize the system pressure.
[0027] The adsorption, regeneration, and cold blowing processes of the three oil and naphthalene removal towers are identical. The entire process is implemented automatically by programmed valves, and operators can adjust the time to control the entire process as needed. The opening and closing sequence of the programmed valves for the oil and naphthalene removal towers is shown in Table 1 below:
[0028] Table 1: Valve Position Table for Oil and Naphthalene Removal Towers
[0029]
[0030]
[0031]
[0032] In Table 1, the set time is the initial value, which can be adjusted appropriately according to the production situation later.
[0033] In the above regeneration process, the initial duration of each stage—adsorption, regeneration, and cold blowing—is set to 8 hours, which can be adjusted later according to actual production needs. Each stage is automatically controlled and regulated by a DCS system, but can be switched to manual adjustment for easier intervention during the regeneration process. The nitrogen-rich gas enters the No. 3 oil and naphthalene removal tower 3 through a regeneration steam heater. If the outlet temperature does not reach 180°C, the regeneration gas electric heater 6 is turned on for electric heating. The gas source used is the medium gas generated by this process, preferably nitrogen-rich gas, but it is not limited to nitrogen-rich gas and can also be hydrogen-rich gas.
Claims
1. A coke oven gas to LNG process deoiling and denaphthalenization column regeneration system, characterized in that: The system includes an oil and naphthalene removal tower, a regulating valve, a regenerated gas cooler (4), a regenerated gas gas-liquid separator (5), a regenerated gas electric heater (6), and a regenerated gas steam heater (7). The oil and naphthalene removal tower is provided with a bottom gas port and a top gas port. The bottom gas port of the oil and naphthalene removal tower is connected to a regenerated gas source through a pipeline and a regulating valve. The bottom gas port of the oil and naphthalene removal tower is also connected to the regenerated gas electric heater (6) and the regenerated gas steam heater (7) in sequence through a pipeline and a regulating valve. The outlet of the regenerated gas steam heater (7) is connected to the top gas port of the oil and naphthalene removal tower through a pipeline and a regulating valve. The top gas port of the oil and naphthalene removal tower is also connected to the regenerated gas cooler (4) and the regenerated gas gas-liquid separator (5) in sequence through a pipeline and a regulating valve.
2. The regeneration system of the deoiling and denaphthalization tower in the coke oven gas to LNG process according to claim 1, characterized in that: The oil and naphthalene removal towers are provided in three sections; the bottom gas ports of the three oil and naphthalene removal towers are all connected to the regeneration gas source through pipelines and regulating valves, and the bottom gas ports are all connected to the regeneration gas electric heater (6) and the regeneration gas steam heater (7) in sequence through pipelines and regulating valves, and the top gas ports are all connected to the regeneration gas cooler (4) and the regeneration gas gas-liquid separator (5) in sequence through pipelines and regulating valves.
3. The regeneration system of the deoiling and denaphthalization tower in the coke oven gas to LNG process according to claim 1, characterized in that: The bottom gas inlet of the oil and naphthalene removal tower is also connected to the coarse desulfurization tower via pipelines and regulating valves.
4. The regeneration system of the deoiling and denaphthalization tower in the coke oven gas to LNG process according to claim 1, characterized in that: The top gas inlet of the oil and naphthalene removal tower is also connected to a venting flare via pipelines and regulating valves.
5. The oil and naphthalene removal tower regeneration system in the coke oven gas to LNG process according to claim 1, characterized in that: The regenerated gas source is also connected to the pipeline between the regenerated gas steam heater (7) and the top gas port of the deoiling and denaphthalene removal tower via pipelines and regulating valves.
6. The regeneration system of the deoiling and denaphthalization tower in the process of preparing LNG from coke oven gas according to any one of claims 1-5, characterized in that: The regenerated gas source is a nitrogen-rich self-cooling box used in the LNG production process from coke oven gas.