Heat source utilization device for aromatic hydrocarbon extraction process
By using the low-pressure superheated steam discharged from the diesel hydrogenation turbine as the heat carrier for the aromatics extraction process, the problem of high cost of medium-pressure superheated steam was solved, the reuse of low-pressure superheated steam was realized, and energy consumption and production costs were reduced.
Patent Information
- Application Number
- CN202520265898.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-02-19
- Publication Date
- 2026-01-06
- Estimated Expiration
- 2035-02-19
AI Technical Summary
In existing aromatic hydrocarbon extraction processes, using medium-pressure superheated steam as the heat carrier for the stripping tower reboiler and the recovery tower reboiler is costly.
The excess low-pressure superheated steam discharged from the diesel hydrogenation turbine is used as the heat carrier for the stripping tower reboiler, recovery tower reboiler, regeneration tower reboiler, benzene tower feed heater, and toluene tower reboiler, thereby reducing the amount of medium-pressure superheated steam used.
The reuse of low-pressure superheated steam has been achieved, reducing energy consumption and production costs, improving the plant's ability to cope with production fluctuations, and significantly reducing energy consumption and costs.
Smart Images
Figure CN223768885U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to the technical field of petroleum processing, specifically relates to a heat source utilization device of aromatic hydrocarbon extraction process. BACKGROUND
[0002] Aromatic hydrocarbon extraction process is a process that takes reforming generating oil, hydrogenation cracking gasoline and the like as raw oil, effectively separates aromatic hydrocarbons from non-aromatic hydrocarbons through solvent extraction or extraction distillation, and obtains high-purity aromatic hydrocarbons and non-aromatic hydrocarbon products. Aromatic hydrocarbon extraction process can be divided into aromatic hydrocarbon liquid-liquid extraction process and aromatic hydrocarbon extraction distillation process according to extraction method, wherein the aromatic hydrocarbon liquid-liquid extraction process is a process that mainly separates aromatic hydrocarbons from hydrocarbon mixtures by using the difference in the solubility of extraction solvents for aromatic hydrocarbons and non-aromatic hydrocarbons. Commonly used extraction solvents in the aromatic hydrocarbon liquid-liquid extraction process include sulfolane, diethylene glycol, triethylene glycol and N-methyl pyrrolidone, etc. Sulfolane has become the most commonly used extraction solvent in industry due to its advantages of good selectivity, strong solubility for aromatic hydrocarbons, large density, stable chemical properties and high thermal stability. The liquid-liquid extraction process using sulfolane as extraction solvent includes six procedures of sulfolane extraction, non-aromatic hydrocarbon water washing, stripping of light components, aromatic hydrocarbon solvent separation, water stripping and solvent regeneration. After pretreatment, the raw oil enters the extraction tower, and after sulfolane extraction, the rich solvent containing aromatic hydrocarbons is formed at the bottom of the extraction tower. The rich solvent from the bottom of the extraction tower enters the stripping tower after heat exchange, and after heating by the stripping tower reboiler, the light non-aromatic hydrocarbons are separated, and then the rich solvent at the bottom of the stripping tower enters the recovery tower, and after heating by the recovery tower reboiler, aromatic hydrocarbons and solvents are separated. The stripping tower reboiler and the recovery tower reboiler are heated by steam as heat carrier, and the existing technology generally uses 2.2 MPa steam prepared by reducing the temperature and pressure of 3.5 MPa medium-pressure superheated steam as the heat carrier of the stripping tower reboiler and the recovery tower reboiler. The 3.5 MPa medium-pressure superheated steam is prepared by a boiler device, and the cost is relatively high. CONTENT OF THE UTILITY MODEL
[0003] In view of the technical problem that the cost of using medium-pressure superheated steam as the heat carrier of the stripping tower reboiler and the recovery tower reboiler after reducing the temperature and pressure is relatively high in the existing aromatic hydrocarbon extraction process, the utility model provides a heat source utilization device of aromatic hydrocarbon extraction process, which uses the surplus low-pressure superheated steam discharged from the diesel hydrogen turbine as the heat carrier of the stripping tower reboiler, the recovery tower reboiler, the regeneration tower reboiler, the benzene tower feed heater and the toluene tower reboiler, reduces the amount of medium-pressure superheated steam, and realizes the reuse of the surplus low-pressure superheated steam.
[0004] The technical scheme of the utility model is as follows:
[0005] A heat source utilization device of aromatic hydrocarbon extraction process, comprising a medium-pressure superheated steam generating device, the medium-pressure superheated steam generating device is connected with the inlet end of a temperature and pressure reducer in communication;
[0006] The diesel oil hydrogenation steam turbine is connected with the inlet end of the desuperheater, and the outlet end of the desuperheater is connected with the outlet end of the desuperheater-reducer in parallel, and then connected with the steam inlets of the stripping column reboiler, the recovery column reboiler, the regeneration column reboiler, the benzene column feed heater and the toluene column reboiler respectively, and the steam outlets of the stripping column reboiler, the recovery column reboiler, the regeneration column reboiler, the benzene column feed heater and the toluene column reboiler are connected with the inlet end of the condensate water heat medium heat exchanger respectively, and the outlet end of the condensate water heat medium heat exchanger is connected with the input end of the condensate water delivery pipe network.
[0007] Further, the medium-pressure superheated steam generating device is a steam boiler, and the steam boiler is used to prepare medium-pressure superheated steam with a pressure of 3.5 MPa.
[0008] Further, the desuperheater-reducer and the desuperheater are connected with the deaerated water source, and the deaerated water source is a deaerated water pipe network.
[0009] Further, the exhaust port of the diesel oil hydrogenation steam turbine is also connected with the input end of the low-pressure steam pipe network. The low-pressure steam discharged from the diesel oil hydrogenation steam turbine is low-pressure superheated steam with a pressure of 1.0 MPa, and the low-pressure superheated steam entering the low-pressure steam pipe network provides heat for the heat tracing system. When the air temperature is high, the heat tracing system needs less heat, and there is a surplus of low-pressure steam. The excess low-pressure steam enters the desuperheater to reduce the temperature and then enters the stripping column reboiler, the recovery column reboiler, the regeneration column reboiler, the benzene column feed heater and the toluene column reboiler respectively to provide heat for the stripping column reboiler, the recovery column reboiler, the regeneration column reboiler, the benzene column feed heater and the toluene column reboiler. The use of the desuperheater can reduce the temperature of the low-pressure superheated steam discharged from the diesel oil hydrogenation steam turbine, and avoid the decomposition of sulfolane caused by the high temperature of the low-pressure superheated steam entering the stripping column reboiler, the recovery column reboiler, the regeneration column reboiler, the benzene column feed heater and the toluene column reboiler.
[0010] Further, the input end of the low-pressure steam pipe network is provided with a low-pressure steam return regulating valve. The low-pressure steam return regulating valve can be used to regulate the flow of low-pressure superheated steam entering the low-pressure steam pipe network to maintain stable pressure and ensure normal operation of the diesel oil hydrogenation steam turbine.
[0011] Further, the condensate water delivery pipe network includes a medium-pressure condensate water pipe network and a low-pressure condensate water pipe network, and the pressure of the medium-pressure condensate water pipe network is 3.5 MPa, and the pressure of the low-pressure condensate water pipe network is 1.0 MPa.
[0012] Further, the steam inlet of the diesel oil hydrogenation steam turbine is connected with the medium-pressure superheated steam generating device.
[0013] Further, the outlet end of the temperature and pressure reducer is provided with a temperature and pressure reducing outlet valve, and the outlet end of the desuperheater is provided with a desuperheater outlet valve.
[0014] The utility model discloses beneficial effect lies in:
[0015] The heat source utilization device of the aromatic extraction process is connected with the exhaust port of the diesel hydrogenation steam turbine and the inlet end of the desuperheater, the desuperheater is used to reduce the temperature of the surplus low-pressure superheated steam discharged by the diesel hydrogenation steam turbine to below the decomposition temperature of the sulfolane extraction solvent, and the chemical stability of the sulfolane is ensured in the process of using the low-pressure superheated steam as the heat carrier of each reboiler; the outlet end of the desuperheater is connected with the steam inlets of the stripping column reboiler, the recovery column reboiler, the regeneration column reboiler, the benzene column feed heater and the toluene column reboiler in parallel with the outlet end of the temperature and pressure reducer, the surplus low-pressure superheated steam discharged by the diesel hydrogenation steam turbine is used to provide heat sources for the reboilers of the aromatic extraction unit and the reboilers of the aromatic rectification unit, the venting amount of the surplus low-pressure superheated steam is reduced, the utilization rate of the low-pressure superheated steam is improved, the use amount of the medium-pressure superheated steam is effectively reduced, the medium and low-pressure steam balance of the whole plant is optimized, the production fluctuation resistance of each device in the aromatic extraction unit and the aromatic rectification unit is improved, and the energy consumption and the cost are significantly reduced. BRIEF DESCRIPTION OF DRAWINGS
[0016] In order to more clearly illustrate the technical scheme of the utility model, the following will be briefly introduced the drawings needed to be used in the description, obviously, the drawings in the following description only some embodiments of the utility model, for those skilled in the art, under the premise of not paying the creative labor, still can obtain other drawings according to these drawings.
[0017] Figure 1 It is the connection relationship schematic diagram of example 1.
[0018] In the figure, 1 is a temperature and pressure reducer, 2 is a desuperheater, 3 is a stripping column reboiler, 4 is a recovery column reboiler, 5 is a regeneration column reboiler, 6 is a benzene column feed heater, 7 is a toluene column reboiler, 8 is a condensate heat medium heat exchanger, 9 is a desuperheater deaerated water regulating valve, 10 is a temperature and pressure reducing outlet valve, 11 is a desuperheater outlet valve, 12 is a medium-pressure condensate valve, 13 is a low-pressure condensate valve, 14 is a low-pressure steam return regulating valve, 15 is a deaerated water pipe network, 16 is a medium-pressure superheated steam generating device, 17 is a low-pressure steam pipe network, 18 is a diesel hydrogenation steam turbine, 19 is a medium-pressure condensate pipe network, 20 is a low-pressure condensate pipe network, and 21 is a temperature and pressure reducer deaerated water regulating valve. DETAILED DESCRIPTION
[0019] To make the objectives, features, and advantages of this utility model more apparent and understandable, the technical solutions of this utility model will be clearly and completely described below with reference to the accompanying drawings of the specific embodiments. Obviously, the embodiments described below are only some embodiments of this utility model, and not all embodiments. Based on the embodiments of this patent, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this patent.
[0020] Example 1
[0021] A heat source utilization device for an aromatic hydrocarbon extraction process, such as Figure 1 As shown, the system includes a medium-pressure superheated steam generator 16, which is a steam boiler used to generate medium-pressure superheated steam at a pressure of 3.5 MPa. The medium-pressure superheated steam generator 16 is connected to the inlet end of a desuperheater / pressure reducer 1. A medium-pressure steam regulating valve is installed between the medium-pressure superheated steam generator 16 and the inlet end of the desuperheater / pressure reducer 1. The outlet end of the desuperheater / pressure reducer 1 is connected to the inlet end of a first branch pipe with one inlet and five outlets. A desuperheater / pressure reducing outlet valve 10 is installed between the outlet end of the desuperheater / pressure reducer 1 and the inlet end of the first branch pipe. The five outlet ends of the first branch pipe are respectively connected to the steam inlet of the stripping tower reboiler 3, the steam inlet of the recovery tower reboiler 4, the steam inlet of the regeneration tower reboiler 5, the steam inlet of the benzene tower feed heater 6, and the steam inlet of the toluene tower reboiler 7. The steam outlets of the stripping tower reboiler 3 and the recovery tower reboiler 4 are also connected. The steam outlets of the regeneration tower reboiler 5, the benzene tower feed heater 6, and the toluene tower reboiler 7 are connected to the five inlet ends of the five-in-one-out manifold, respectively. Flow regulating valves are installed at the steam outlet ends of the stripping tower reboiler 3, the recovery tower reboiler 4, the regeneration tower reboiler 5, the benzene tower feed heater 6, and the toluene tower reboiler 7, respectively. The outlet end of the manifold is connected to the inlet end of the condensate heat exchanger 8. The outlet end of the condensate heat exchanger 8 is connected to the inlet end of the second branch pipe with one inlet and two outlets. The two outlet ends of the second branch pipe are connected to the medium-pressure condensate network 19 and the low-pressure condensate network 20, respectively.
[0022] The diesel hydrogenation turbine 18 is connected to the medium-pressure superheated steam generator 16. The exhaust port of the diesel hydrogenation turbine 18 is connected to the inlet end of a third shunt pipe with two outlet ends, which are respectively connected to the input end of the low-pressure steam pipe network 17 and the inlet end of the desuperheater 2. The outlet end of the desuperheater 2 is connected in parallel to the outlet end of the desuperheating and pressure-reducing device 1, and then connected to the inlet end of the first shunt pipe. The low-pressure steam return regulating valve 14 is arranged on the branch pipe of the third shunt pipe where the input end of the low-pressure steam pipe network 17 is located. The desuperheater outlet valve 11 is arranged between the outlet end of the desuperheater 2 and the inlet end of the first shunt branch pipe. The desuperheating water inlets of the desuperheating and pressure-reducing device 1 and the desuperheater 2 are both connected to the deaerated water pipe network 15. The desuperheating and pressure-reducing device deaerated water regulating valve 21 and the desuperheater deaerated water regulating valve 9 are respectively arranged between the desuperheating water inlets of the desuperheating and pressure-reducing device 1 and the desuperheater 2 and the deaerated water pipe network 15.
[0023] Working principle: when the winter temperature is low, the 1.0MPa low pressure superheated steam discharged by the diesel hydrogenation steam turbine enters the 1.0MPa low pressure steam pipe network entirely, providing heat for the heat tracing system of the plant. When the temperature rises, the heat tracing system requires less heat, and the 1.0MPa low pressure superheated steam discharged by the diesel hydrogenation steam turbine has a surplus after entering the 1.0MPa low pressure steam pipe network to provide heat for the heat tracing system. In the case of surplus 1.0MPa low pressure superheated steam, open the low pressure steam return regulating valve, the deaerating water regulating valve of the desuperheater, and use the desuperheater to cool the 1.0MPa low pressure superheated steam in the desuperheater. When the temperature of the 1.0MPa low pressure superheated steam in the desuperheater drops to 220℃, open the desuperheater outlet valve to make the 1.0MPa low pressure superheated steam enter the aromatic extraction unit. Gradually close the medium pressure steam regulating valve and the deaerating water regulating valve of the desuperheater, and then close the desuperheater outlet valve after the medium pressure steam regulating valve and the deaerating water regulating valve of the desuperheater are fully closed, so as to switch the 3.5MPa medium pressure superheated steam entering the aromatic extraction unit to 1.0MPa low pressure superheated steam. After the switching is completed, slightly open the steam regulating valve for emergency drainage. When the 1.0MPa low pressure superheated steam discharged by the diesel hydrogenation steam turbine cannot guarantee the normal operation of the reboilers in the aromatic extraction unit due to flow fluctuation, or when the reboiler temperature is difficult to raise due to bad weather, the desuperheater can be switched back. Then open the low pressure condensate valve and close the medium pressure condensate valve to switch the 3.5MPa medium pressure condensate network pipe of the aromatic extraction unit to the 1.0MPa low pressure condensate network pipe, so as to prevent the condensate from being difficult to send out due to the decrease of the front steam pressure. After the switching is completed, adjust the flow regulating valves respectively arranged at the steam outlet ends of the stripping column reboiler, the recovery column reboiler, the regeneration column reboiler, the benzene column feed heater and the toluene column reboiler, so as to ensure the stable temperature control parameters of each column. Adjust the low pressure steam return regulating valve and the deaerating water regulating valve of the desuperheater in time according to the consumption of 1.0MPa low pressure superheated steam, so as to ensure the stable steam pressure discharged by the diesel hydrogenation steam turbine, and prevent the steam pressure fluctuation from affecting the normal operation of the diesel hydrogenation steam turbine.
[0024] The above description of disclosed embodiments enables those skilled in the art to carry out or use the present application. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to these embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.
Claims
1. A heat source utilization device for an aromatic hydrocarbon extraction process, comprising a medium-pressure superheated steam generating device, characterized in that, The medium-pressure superheated steam generating device is connected with an inlet end of the desuperheater. The diesel oil hydrogenation steam turbine is further connected with an input end of a low-pressure steam pipe network.
2. The apparatus according to claim 1, wherein the heat source is a heat source of an aromatic extraction process. The medium-pressure superheated steam generating device is a steam boiler.
3. The apparatus of claim 1 wherein the heat source is a process heat source of an aromatic extraction process. The desuperheater water inlet of the desuperheater and the desuperheater water inlet of the desuperheater are both connected with an oxygen removal water source.
4. The apparatus of claim 1 wherein the heat source is a process heat source of an aromatic extraction process. The exhaust port of the diesel oil hydrogenation steam turbine is further connected with an input end of a low-pressure steam pipe network.
5. The apparatus of claim 4 wherein the heat source is a heat exchanger. The input end of the low-pressure steam pipe network is provided with a low-pressure steam return regulating valve.
6. The apparatus of claim 1 wherein the heat source is a process heat source of an aromatic extraction process. The condensate delivery pipe network includes a medium-pressure condensate pipe network and a low-pressure condensate pipe network.
7. The apparatus of claim 1 wherein the heat source is a process heat source of an aromatic extraction process. The steam inlet of the diesel oil hydrogenation steam turbine is connected with the medium-pressure superheated steam generating device.
8. The apparatus according to claim 1, wherein The outlet end of the desuperheater is provided with a desuperheater outlet valve.