Anti-corrosion control system for low-temperature methanol washing process

Abstract

The utility model discloses an anti-corrosion control system for a low-temperature methanol washing process, which comprises an alkali liquor adding tank used for storing and preparing alkali liquor with the concentration of 2%; the alkali liquor filling pump is connected to the alkali liquor dosing tank and is used for conveying the prepared 2% alkali liquor to an ammonia washing tower and a methanol-water separation tower in the production system; the alkali liquor dosing tank liquid level meter is arranged on the alkali liquor dosing tank and is used for monitoring the liquid level in the alkali liquor dosing tank in real time and sending out an alarm and interlocking protection signal; the DCS control system is used for automatically controlling the supplement amount of alkali liquor according to preset program setting and ensuring safe operation, the alkali liquor filling pump and the alkali liquor dosing tank liquid level meter are both connected with the DCS control system, 1-2% of alkali liquor is supplemented through online continuous operation, the PH value of condensate of the methanol-water separation tower and the ammonia washing tower is controlled to be 7-8, and therefore the problem of equipment corrosion is solved.

Description

TECHNICAL FIELD

[0001] The utility model relates to a chemical industry technical field, specifically a kind of anticorrosion control system for low temperature methanol washing process, to solve the corrosion problem caused by low PH value in the low temperature methanol washing device ammonia washing tower and methanol water separation tower. BACKGROUND

[0002] In prior art, low temperature methanol washing device appears corrosion in the inner wall of ammonia washing tower and methanol water separation tower during operation process due to low PH value (about 5) of process condensate wastewater, there is potential leakage risk, which affects the stable operation of device. Similar problems exist in devices using similar process technology at home and abroad. UTILITY MODEL CONTENT

[0003] In view of the above problems, the utility model provides a kind of low temperature methanol washing process anticorrosion control system, by on-line continuous operation supplement 1-2% lye, control methanol water separation tower, ammonia washing tower condensate PH value is 7-8, to solve the equipment corrosion problem.

[0004] In order to achieve the above purpose, the utility model is realized by the following technical scheme:

[0005] The utility model relates to a kind of low temperature methanol washing process anticorrosion control system, comprising:

[0006] Lye dosing tank is used to store and configure 2% concentration lye;

[0007] Lye filling pump is connected to lye dosing tank, and is used to deliver the 2% lye configured to ammonia washing tower and methanol water separation tower in production system;

[0008] Lye dosing tank liquid level meter is installed on lye dosing tank, for real-time monitoring the liquid level in lye dosing tank, and sends out alarm and interlock protection signal;

[0009] DCS control system automatically controls the supplement amount of lye according to preset program setting, to ensure safe operation, the lye filling pump, lye dosing tank liquid level meter are connected with DCS control system.

[0010] Preferably, the lye dosing tank is vertical cylindrical atmospheric vessel, and its volume is 5.0m 3 (φ1800×h2200mm). And the DCS control system automatically supplements diluted lye into ammonia washing tower and methanol water separation tower by adjusting the range of pry-mounted pump according to the PH value of condensate sent from ammonia washing tower and methanol water separation tower, to maintain the PH value of system condensate in 7-8 range.

[0011] Preferably, the caustic soda liquid level gauge can send an alarm indication through the DCS system when the liquid level reaches 1.9 meters or is lower than 0.5 meters, and can send a interlocking signal to stop the operation of the caustic soda filling pump through the DCS system when the liquid level approaches the caustic soda filling pump inlet.

[0012] Preferably, the DCS control system can automatically adjust the range of the skid-mounted pump according to the PH value of the condensate outside the system, so as to accurately control the filling amount of the caustic soda and ensure the stability of the PH value of the condensate in the system.

[0013] Preferably, the caustic soda filling tank receives 30% concentration liquid caustic soda and production water through the pipe gallery, and after being diluted to 2% concentration by the stirrer in the caustic soda filling tank, the caustic soda is delivered to the production system by the caustic soda filling pump.

[0014] Beneficial effects: simple structure, strong practicability, 1-2% caustic soda is supplemented through online continuous operation, the PH value of the condensate of the methanol water separation tower and the ammonia washing tower is controlled at 7-8, so that the equipment corrosion problem is solved. Through the implementation of the utility model, the PH value of the wastewater of the ammonia washing tower and the methanol water separation tower in the low-temperature methanol washing device is stably controlled at about 7, the corrosion problem caused by low PH value is greatly reduced, the parking and maintenance frequency caused by corrosion of the device is reduced, the labor intensity is reduced, the manpower and financial resources are saved, and the personal safety factor is reduced. BRIEF DESCRIPTION OF DRAWINGS

[0015] Figure 1 It is a structural schematic diagram of the utility model. DETAILED DESCRIPTION

[0016] The technical solutions in the embodiments of the utility model will be clearly and completely described below with reference to the drawings in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by those skilled in the art without creative labor belong to the protection scope of the utility model.

[0017] The low-temperature methanol washing process corrosion control system of the utility model, including caustic soda liquid level gauge 3 and DCS control system. Among them, the caustic soda liquid level gauge is used for storing and configuring 2% concentration caustic soda, the caustic soda filling pump is used for delivering the configured caustic soda to the ammonia washing tower and the methanol water separation tower in the production system, the caustic soda liquid level gauge is used for real-time monitoring of liquid level and sending alarm and interlocking protection signals, and the DCS control system automatically controls the supplement amount of caustic soda according to the preset program. The caustic soda liquid level gauge is a vertical cylindrical atmospheric vessel, with a volume of 5.0m 3(φ1800×h2200mm), can be designed according to the production device demand.DCS control system according to the ammonia washing tower and the methanol water separation tower outside the PH value of the condensate, by adjusting the pry dress pump's range, automatically to the system supplement dilution after lye, to maintain the PH value of the system condensate in 7-8 range.When the lye dosing tank liquid level reaches 1.9 meters or less than 0.5 meters, the DCS system sends an alarm indication, and when the liquid level is close to the lye filling pump inlet, the interlocking signal is sent to stop the operation of the lye filling pump, to protect the equipment and prevent damage from idling.

[0018] In practical application, through the pipe gallery, 30% concentration of liquid caustic and production water are transported to the lye filling tank, and after dilution to 2% concentration by stirring, according to the PH value of the condensate outside the ammonia washing tower and the methanol water separation tower, the dilution after lye is transported to the system by adjusting the pry dress pump's range, to maintain the PH value of the system condensate in 7-8 range. The sampling detection result shows that the PH value of each tower bottom wastewater is stably controlled at about 7, which achieves the expected effect.

[0019] The prior art DCS (Distributed Control System) control system, the distributed control system controller is a key component in the field of industrial automation, which is responsible for monitoring and controlling various parameters and devices in industrial processes. The following is a detailed introduction to the structure and design principles of the DCS controller:

[0020] I. Structure The DCS controller usually has the following core components: Processor unit: the core of the DCS controller, responsible for executing control algorithms, data processing and communication tasks. The processor unit usually uses high-performance microprocessors or digital signal processors DSP to meet the requirements of real-time and reliability. Input / output module (I / O module): responsible for data exchange with field devices, including sensors, actuators, valves, etc. The I / O module includes analog input / output modules, digital input / output modules, etc., for processing different types of signals. Communication interface: used for communication with other DCS components such as operator stations, engineer stations, other controllers, etc. Common communication protocols include Ethernet, fieldbus such as Modbus, Profibus, etc. and special communication protocols. Power module: provides stable and reliable power supply for the controller. Usually adopts redundant design to improve the reliability and availability of the system. Storage unit: used to store control algorithms, configuration parameters, historical data, etc. The storage unit usually uses non-volatile memory to ensure that data is not lost during power failure.

[0021] II. Design Principles The design principles of DCS controllers are mainly based on the following aspects: Distributed control: The control task is distributed to multiple controllers, each of which is responsible for controlling a specific industrial process or equipment. This design improves the reliability and flexibility of the system, reducing the impact of a single controller failure on the entire system. Modular design: The controller adopts a modular design, which is convenient for expansion and maintenance. Users can add or delete I / O modules, communication interfaces, and other components according to actual needs to adapt to different industrial application scenarios. Real-time performance: The controller needs to quickly respond to changes in signals from field devices and execute control algorithms in real time. To this end, the controller usually uses high-speed processors and optimized control algorithms to ensure real-time performance and accuracy. Reliability: The controller adopts redundant design, such as redundant power supply, redundant communication interface, etc., to improve the reliability of the system. At the same time, the controller also has fault detection and recovery functions, which can automatically switch to backup devices or take other recovery measures when a fault occurs. Openness: The controller supports multiple communication protocols and interface standards, making it easy to integrate and interoperate with other systems and devices. This openness enables the DCS system to flexibly adapt to different industrial application scenarios and user needs. Ease of use: The controller is usually equipped with a friendly user interface and configuration tools, making it easy for engineers to configure, debug, and maintain the system. These tools usually provide graphical interfaces, online help, and diagnostic functions to reduce the difficulty of engineers' work and improve work efficiency. In summary, DCS controllers have complex structures and advanced design principles, which enable DCS systems to efficiently monitor and control industrial processes, improving production efficiency, product quality, and safety. The above is a technical description of the DCS controller in the prior art.

[0022] As Figure 1 The specific embodiment of the low-temperature methanol washing process corrosion control system is shown in the figure, which is a low-temperature methanol washing process corrosion control system, comprising:

[0023] The alkali solution filling tank 1 is used to store and configure 2% concentration of alkali solution; the alkali solution filling tank receives 30% concentration of liquid alkali and production water through the pipe gallery, and after dilution to 2% concentration by the stirrer in the alkali solution filling tank, the alkali solution is delivered to the production system by the alkali solution filling pump;

[0024] The alkali solution filling pump 3 is connected to the alkali solution filling tank and used to deliver the configured 2% alkali solution to the ammonia washing tower and methanol water separation tower in the production system, a plurality of outer delivery pipelines with the alkali solution filling pump 3 are connected to the alkali solution filling tank, and pressure sensors, temperature sensors, flow sensors, check valves and various control valves are arranged on the outer delivery pipelines.

[0025] The alkali solution filling tank liquid level meter 2 is installed on the alkali solution filling tank and used to monitor the liquid level in the alkali solution filling tank in real time and send alarm and interlock protection signals;

[0026] DCS control system, according to the preset program (the application does not limit the design of the program, depends on the traditional DCS control system function, for parameter design according to actual needs to carry out corresponding selection, see the above DCS controller description) Set the automatic control of alkali liquid supplement, ensure safe operation, the alkali liquid filling pump, alkali liquid dosing tank liquid level meter are connected with DCS control system.

[0027] The alkali dosing tank is a vertical cylindrical atmospheric pressure container, and the volume is 5.0m 3 (φ1800×h2200mm). And the DCS control system according to the PH value of the condensate sent out of the ammonia washing tower and the methanol water separation tower, by adjusting the range of pry pump, automatically supplement the diluted alkali liquid to the ammonia washing tower and the methanol water separation tower, to maintain the PH value of the system condensate in the range of 7-8. The alkali dosing tank liquid level meter can send alarm indication through the DCS system when the liquid level reaches 1.9 meters or is lower than 0.5 meters, and can send interlocking signal to stop the operation of the alkali liquid filling pump through the DCS system when the liquid level approaches the alkali liquid filling pump inlet. The DCS control system can automatically adjust the range of pry pump according to the PH value of the condensate sent out of the system, to accurately control the filling amount of alkali liquid, and ensure the stability of the PH value of the system condensate.

[0028] Finally, it should be noted that the utility model is not limited to the above embodiments, but can also have many variations. All variations that can be directly derived or conceived from the disclosed content by those of ordinary skill in the art should be considered within the scope of the utility model.

Claims

1. A low temperature methanol wash process corrosion control system characterized by, The application relates to a kind of alkali liquid feeding tank and alkali liquid feeding pump system, which comprises: An alkali liquid feeding tank for storing and configuring 2% concentration alkali liquid; An alkali liquid feeding pump connected to the alkali liquid feeding tank for delivering the configured 2% alkali liquid to ammonia washing tower and methanol water separation tower in the production system; An alkali liquid feeding tank liquid level meter installed on the alkali liquid feeding tank for real-time monitoring of the liquid level in the alkali liquid feeding tank and sending alarm and interlock protection signals; A DCS control system for automatically controlling the supplement of alkali liquid according to preset program settings to ensure safe operation, wherein the alkali liquid feeding pump and the alkali liquid feeding tank liquid level meter are connected to the DCS control system.

2. A corrosion control system for an amine unit according to claim 1, wherein The alkali liquid feeding tank is a vertical cylindrical atmospheric pressure container with a volume of 5.0 m³.

3. The corrosion control system for an amine unit according to claim 1 or 2, wherein When the liquid level reaches 1.9 meters or is lower than 0.5 meters, the alkali liquid feeding tank liquid level meter can send an alarm indication through the DCS system, and when the liquid level approaches the inlet of the alkali liquid feeding pump, the DCS system can send an interlock signal to stop the operation of the alkali liquid feeding pump.

4. The corrosion control system for an amine unit according to claim 1, wherein The DCS control system can automatically adjust the range of the skid-mounted pump according to the PH value of the condensate sent out of the system to accurately control the feeding amount of alkali liquid and ensure the stability of the PH value of the system condensate.

5. The corrosion control system for an amine unit according to claim 1, wherein The alkali liquid feeding tank receives 30% concentration liquid alkali and production water through a pipe gallery, dilutes the liquid to 2% concentration through a stirrer in the alkali liquid feeding tank, and then delivers the liquid to the production system through the alkali liquid feeding pump.

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