CN115331741A - Catalytic cracking absorption stability real-time optimization simulation system - Google Patents
Catalytic cracking absorption stability real-time optimization simulation system Download PDFInfo
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Abstract
The invention relates to a catalytic cracking absorption stability real-time optimization simulation system; the system consists of a real-time optimization simulation interface, a real-time optimization simulation calculation file and a real-time data acquisition module; the real-time optimization simulation interface is used for providing a human-computer interaction window, a user modifies the unit processing cost and the product price information on the real-time optimization simulation interface, and all real-time optimization results are fed back to the user through the real-time optimization simulation interface; the real-time optimization simulation calculation file is completed by one or more AspenPlus process simulation files with stable catalytic cracking absorption, and the corresponding AspenPlus files are automatically identified and called by a real-time data acquisition module for simulation calculation; the real-time data acquisition module acquires process data and assay analysis data in the production process in real time by using a data interface, and the data acquisition interface is communicated with the real-time database and the LIMS database through ODBC. And providing real-time optimal process parameters of the catalytic cracking absorption stabilizing unit for operators.
Description
Technical Field
The invention belongs to the field of petroleum processing, relates to a real-time optimization simulation system, and particularly relates to a catalytic cracking absorption stability real-time optimization simulation system.
Background
Catalytic cracking is an important secondary processing process in the field of petroleum processing, and generally comprises three parts, namely a reaction-regeneration system, a fractionation system and an absorption stabilization system, wherein the absorption stabilization system is used for separating rich gas and crude gasoline into dry gas (C2 and below C2), liquefied gas (C3 and C4) and stabilized gasoline (more than C4) with qualified vapor pressure, and is one of important components influencing the economic benefit of oil refining.
The catalytic cracking absorption stabilizing system mainly comprises an absorption tower, a desorption tower, a reabsorption tower and a stabilizing tower, wherein the operation of the towers is mutually related and restricted, and in order to maximize the economic benefit of the device, the modeling optimization is usually carried out by adopting process simulation software. Therefore, it is necessary to develop a catalytic cracking absorption stabilization real-time optimization simulation system, and the real-time simulation system can provide real-time optimal process parameters of a catalytic cracking absorption stabilization unit for device operators, so that the device is always in an optimized operation state, and the economic benefit of the device is improved.
Disclosure of Invention
In order to solve the problems and the actual requirements, the invention develops a catalytic cracking absorption stabilization real-time optimization simulation system which can provide real-time optimal process parameters of a catalytic cracking absorption stabilization unit for device operators.
In order to achieve the purpose, the invention adopts the following technical scheme:
a catalytic cracking absorption stability real-time optimization simulation system is composed of a real-time optimization simulation interface, a real-time optimization simulation calculation file and a real-time data acquisition module; the real-time optimization simulation interface is used for providing a human-computer interaction window, a user modifies the unit processing cost and the product price information on the real-time optimization simulation interface, and all real-time optimization results are fed back to the user through the real-time optimization simulation interface; the real-time optimization simulation calculation file is completed by one or more AspenPlus process simulation files with stable catalytic cracking absorption, and the corresponding AspenPlus files are automatically identified and called by a real-time data acquisition module for simulation calculation; the real-time data acquisition module acquires process data and assay analysis data in the production process in real time by using a data interface, and the data acquisition interface is communicated with the real-time database and the LIMS database through ODBC.
The catalytic cracking absorption stabilization Aspen Plus process simulation file is characterized in that according to a catalytic cracking absorption stabilization process flow, an Aspen Plus process simulation software is used for establishing a catalytic cracking absorption stabilization optimization model, economic benefits are maximized as a target function, and optimal process parameters are calculated under the condition that constraint conditions are met.
The constraint conditions include, but are not limited to, the upper limit of volume fraction of C2 and C5 in the product liquefied gas, the upper and lower limits of tower kettle temperature of an absorption tower, a desorption tower or a stabilizing tower, the temperature difference of cold and hot ends of a heat exchanger and the upper limit of heat load.
The optimal process parameters include but are not limited to absorbent flow, temperature, supplementary absorbent flow, temperature, desorber kettle temperature or stabilizer reflux ratio.
The real-time optimization simulation interface provided by the invention is consistent with a DCS system interface of a catalytic cracking absorption stabilizing device, the real-time optimization simulation interface is added into a Visual Basic window, then a Visual Basic control is added on the interface, and a user modifies the unit processing cost and the product price information through the Visual Basic control on the window.
The real-time optimization simulation calculation file called in the invention adopts the file name related to the load of the catalytic cracking absorption stabilizing device and the product quality, and different Aspen Plus files correspond to different device loads and product qualities. Under certain constraint conditions, the economic benefit maximization is realized by adjusting the process parameters. The constraint conditions in the document include but are not limited to the upper limit of the volume fraction of C2 and C5 in the product liquefied gas, the upper and lower limits of the tower temperature of the absorption tower, the desorption tower and the stabilizing tower, the temperature difference of the cold end and the hot end of the heat exchanger, the upper limit of the heat load and the like, and the assignment range is in a reasonable process parameter range; the adjustable process parameters set in the document include but are not limited to the flow rate and temperature of the absorbent, the temperature of the tower kettle of the desorption tower and the reflux ratio of the stabilizing tower; the objective function for maximizing economic benefit in the file is: max = Σ i V i *earn i -∑ j V j *cost j In which V is i Denotes the product quantity, earn i Indicating product price, V j Represents utility consumption, cost j Representing utility prices, i, j belong to the set of product variables and utility variables, respectively.
The real-time data acquisition module provided by the invention is communicated with the real-time database and the LIMS database through the ODBC interface, can acquire process data and assay analysis data in the production process in real time, automatically calls a corresponding Aspen Plus file according to the acquired real-time data to solve the optimal process parameters by a real-time optimization simulation calculation file, and directly displays the operation result on a window through a Visual Basic control.
The invention has the following beneficial effects: the real-time optimization simulation system is simple to operate, only the current public engineering unit price and the current product unit price need to be input by an operator in the real-time optimization process, and the need that the optimizer has profound professional knowledge and software use capability is avoided; the real-time simulation system can provide real-time optimal process parameters of the catalytic cracking absorption stabilizing unit for device operators, so that the device is always in an optimal running state, the simulation system is simple to operate, and the economic benefit of the device is improved.
Drawings
FIG. 1 is an interface diagram of a catalytic cracking absorption stabilization real-time optimization simulation system provided by the invention.
FIG. 2 is a frame diagram of a catalytic cracking absorption stabilization real-time optimization simulation system according to the present invention.
Detailed Description
The invention will now be described in further detail with reference to the figures and examples.
A construction framework of a catalytic cracking absorption stabilization real-time optimization simulation system comprises the following steps:
as shown in fig. 2, the construction framework of the present invention is composed of a simulation interface, an ASPEN simulation calculation, a data acquisition module, a real-time database and a LIMS database, wherein the simulation interface is used for receiving and feeding back ASPEN simulation calculation data, the data acquisition module acquires the LIMS database, the real-time database data and data information manually input by the simulation interface in real time, compares the acquired data with ASPEN simulation calculation files, selects corresponding ASPEN simulation calculation files for optimization calculation, and feeds back the calculation results to the simulation interface.
A catalytic cracking absorption stability real-time optimization simulation system development process comprises the following steps:
(1) And (3) modeling the catalytic cracking absorption stabilization process by using process simulation software Aspen Plus, and establishing Aspen Plus model files under different working conditions according to the load of the device and the product quality so that a simulation calculation result is consistent with actual operation data of the device.
The process flow of the Aspen Plus model document of the present invention is shown in FIG. 1. And (3) compressing the rich gas from the top of the fractionating tower to 1.6-1.7 Mpa by a compressor, mixing the compressed rich gas with the bottom oil of the absorption tower (C304) and the top gas of the desorption tower (C306), cooling to normal temperature, and then feeding the cooled rich gas into an oil-gas separator (D301) to separate the rich gas and the condensed oil. The rich gas enters an absorption tower, and the condensed oil enters a desorption tower.
The operating pressure of the absorption tower is 1.4MPa, the average absorption temperature is about 45 ℃, rich gas enters from the lower part of the absorption tower, an absorbent (crude gasoline) from the top of the fractionating tower and a supplementary absorbent from a stabilizer are fed from the top and reversely contact with the rich gas to absorb and remove light hydrocarbon components in the rich gas.
The lean gas from the top of the absorption tower enters the bottom of a reabsorption tower (C305) and is in countercurrent contact with lean absorption oil (light diesel oil) to further remove light hydrocarbon components in the lean gas, the top pressure of the reabsorption tower is 1.35MPa, the average temperature is 45 ℃, and dry gas discharged from the top of the reabsorption tower enters a refinery gas system after being desulfurized. The tower bottom rich absorption oil returns to the fractionating tower.
The desorption tower is used for desorbing C2 components carried in the condensed oil, and guarantees that qualified liquefied gas LPG is produced by the stabilizing tower (C307). Feeding condensed oil from the oil-gas separator from the top of the desorption tower, obtaining deethanized gasoline from the bottom of the tower under the action of an intermediate reboiler and a reboiler at the bottom of the tower, and feeding the deethanized gasoline into the stabilizing tower. And the condensed oil from the oil-gas separator exchanges heat with stable gasoline and then enters the upper part of the desorption tower.
The deethanized gasoline at the bottom of the desorber exchanges heat with the stable gasoline to about 150 ℃, and then enters the stabilizing tower. The operation pressure at the top of the stable tower is 1.2MPa. And C4 and the light components below C4 are extracted from the top of the stabilizing tower, cooled to normal temperature, enter a reflux tank, one part of the light components is used as the reflux of the top of the tower, and the other part of the light components is used as a liquefied gas product and sent out of the device. And a stable gasoline product at the bottom of the tower is sent out.
(2) Establishing an objective function Max = Σ for maximizing economic benefit in an Aspen Plus model file by using a model analysis tool in Aspen Plus software i V i *earn i -∑ j V j *cost j And realizing the optimization calculation of the simulation system.
(3) A form is created in Visual Basic, and a simulation interface is added to the DCS system interface of the device (figure 1). Adding a Visual Basic text box control and a command button control on a simulation interface; the textbox control is used for realizing the input of the adjustment parameters and the output of the calculation result, and the command button control is used for realizing the running of the simulation system and the exit of the system.
(4) As shown in fig. 1, the text box for implementing the input of the adjustment parameter and the output of the calculation result includes a stable gasoline unit price, a liquefied gas unit price, a dry gas unit price, a water vapor unit price, an electricity price, an absorbent flow rate, an absorbent temperature, a dry gas flow rate, a tower bottom temperature, a reflux ratio, a liquefied gas flow rate, a stable gasoline flow rate, a supplementary absorbent flow rate, and a supplementary absorbent temperature; the command button controls for implementing the operation and exit of the simulation system are located at the bottom of fig. 1, and are respectively operated and exited.
(5) And writing an Aspen Plus simulation file, a simulation interface and an interface program of a real-time data acquisition module by using Visual Basic. The interface program realizes correct selection of the Aspen Plus simulation files under different working conditions according to the data information of the real-time acquisition module.
A use method of a catalytic cracking absorption stability real-time optimization simulation system comprises the following steps:
(1) Clicking an 'operation' button at the bottom of a catalytic cracking absorption stabilization real-time optimization simulation system interface in the figure 1, and performing optimization calculation on real-time acquisition device operation data, products and public engineering data and selection of an Aspen Plus model file suitable for the current working condition by the simulation system.
(2) The unit processing cost and product price information is modified at the top of fig. 1 in the simulation system.
(3) Clicking a 'run' command button control at the bottom of the drawing 1 in a simulation system, calling an Aspen Plus simulation file by the simulation system to perform optimization operation, displaying the operated adjustment parameter on the upper part or the lower part of the corresponding text box control in a red font, and always displaying the adjustment parameter as real-time acquisition data of the parameter in the corresponding text box.
(4) The simulation system is exited by clicking on the "exit" command button control of figure 1.
Example (b):
(1) The unit price of liquefied gas (top of fig. 1) was modified from 3450 to 5500, the unit price of stabilized gasoline was modified from 4010 to 4230, and the unit price of water vapor was modified to 120 in the simulated system.
(2) Clicking a 'run' command button control at the bottom of the graph 1 in a simulation system, calling an Aspen Plus simulation file by the simulation system to perform optimization operation, wherein a red font appears on the upper part of a dry airflow text box, the numerical value is 2968.5, the current actual acquired data is 3268.4, and the dry airflow is reduced by 299.9; the red numerical value at the upper part of the liquefied gas flow text box is 25.69, the red numerical value at the upper part of the stable gasoline flow text box is 57.65, the red numerical value at the upper part of the reflux ratio text box is 2.97, the red numerical value at the lower part of the temperature of the supplementary absorbent is 33.60, the red numerical value at the upper part of the flow of the supplementary absorbent is 30.53, the red numerical value at the upper part of the flow text box of the absorbent is 32.01, and the red numerical value at the upper part of the temperature text box of the tower bottom is 136.71.
(3) The simulation system is exited by clicking on the "exit" command button control of figure 1.
While the methods and techniques of the present invention have been described in terms of preferred embodiments, it will be apparent to those of ordinary skill in the art that variations and/or modifications of the methods and techniques described herein may be made without departing from the spirit and scope of the invention. It is expressly intended that all such similar substitutes and modifications apparent to those skilled in the art are deemed to be within the spirit, scope and content of the invention.
Claims (4)
1. A catalytic cracking absorption stability real-time optimization simulation system is characterized in that the real-time optimization simulation system consists of a real-time optimization simulation interface, a real-time optimization simulation calculation file and a real-time data acquisition module; the real-time optimization simulation interface is used for providing a human-computer interaction window, a user modifies the unit processing cost and the product price information on the real-time optimization simulation interface, and all real-time optimization results are fed back to the user through the real-time optimization simulation interface; the real-time optimization simulation calculation file is completed by one or more AspenPlus process simulation files with stable catalytic cracking absorption, and the corresponding AspenPlus files are automatically identified and called by a real-time data acquisition module to carry out simulation calculation; the real-time data acquisition module acquires process data and assay analysis data in the production process in real time by using a data interface, and the data acquisition interface is communicated with the real-time database and the LIMS database through ODBC.
2. The catalytic cracking absorption stability real-time optimization simulation system according to claim 1, wherein the catalytic cracking absorption stability Aspen Plus process simulation file is a catalytic cracking absorption stability optimization model established by using Aspen Plus process simulation software according to a catalytic cracking absorption stability process flow, and optimal process parameters are calculated under the condition that constraint conditions are met by taking economic benefits maximization as an objective function.
3. The catalytic cracking absorption stabilization real-time optimization simulation system according to claim 2, wherein the constraint conditions include, but are not limited to, upper limits of volume fractions of C2 and C5 in the product liquefied gas, upper and lower limits of tower kettle temperatures of an absorption tower, a desorption tower or a stabilization tower, temperature differences between a cold end and a hot end of a heat exchanger, and upper limits of heat loads.
4. The catalytic cracking absorption stability real-time optimization simulation system according to claim 2, wherein the optimal process parameters include, but are not limited to, absorbent flow, temperature, make-up absorbent flow, temperature, desorber kettle temperature or stabilizer reflux ratio.
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