Application of the hottest DCS control system in c

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Application of DCS control system in crude oil stabilization compressor

Abstract: This paper introduces the application of DCS system in compressor device, including DCS system characteristics, automatic control transformation scheme, equipment and instrument selection, alarm measures, etc

1. Introduction

crude oil stabilization compressor is an important equipment for crude oil stabilization and oil and gas treatment in the production of oil and gas gathering and transportation system. The process flow of this device is complex, the production process is flammable and explosive, and the control requirements for production parameters are strict. Most of the combined stations in the oil and gas gathering and transportation system use compressors as crude oil stabilization and oil and gas treatment devices

at present, all compressor control instruments are electric II instruments, which supply 220V power, with low explosion-proof grade and no data remote transmission function; Most parameters are adjusted manually or monitored by simple instruments; The failure rate of the instrument is high and the control efficiency is low; The increasing concentration or monopoly of the production industry is an important trend in the development of biomedical materials industry. When there is a fault, it is not easy to find the cause of the accident, resulting in many unstable factors such as production and safety; At the same time, the historical data of production parameters cannot be stored, which is not convenient for production management, which seriously limits the further improvement of the automation technology of the compressor device and becomes a bottleneck that hinders the automation transformation of the device In order to overcome the above problems, improve the automatic operation ability of the compressor, achieve the purpose of early warning, ensure the output and quality of crude oil, and improve the export rate of crude oil, it is imperative to apply DCs as a new control system to transform the device

2. Overall scheme design

less waste heat

2.1. Introduction to the overall scheme

the compressor device has more than 30 important production parameters, and each production parameter restricts and affects each other. The device has high requirements for production parameters. The specific requirements are as follows: inlet pressure 0.35Mpa, exhaust temperature>85 ℃, oil pressure 65 ℃, audible and visual alarm must be carried out to remind operators to deal with it in time to ensure production safety; If the exhaust pressure is>0.45mpa, the exhaust temperature is>95 ℃, and the oil pressure is 70 ℃, the machine must be shut down. The production parameters of the compressor, such as temperature and pressure, are divided into two ways to input the control system: one way is introduced into the alarm setter, which detects the production parameters according to the alarm value set by the internal parameters. If the production parameters are abnormal, it will send out a fault alarm signal and stop the compressor to ensure the safety of equipment and production; On the other hand, DCS system is introduced for routine display of parameters and flow picture. In case of failure or compressor shutdown, audible and visual alarm will be given to remind operators, effectively preventing misoperation and urgently eliminating dangerous situations. The system provides the function of browsing and querying historical data, which can track and query historical data, and provide convenience for analyzing the cause of failure. The whole system complements each other, with friendly and intuitive interface and convenient operation, which not only saves human resources, but also improves work efficiency

2.2 technical introduction of control system

the representative systems are FOCS system and Macs system. These two control systems have open architecture, which can provide multi-layer open data interface, powerful processing function and convenient configuration; Support a variety of on-site standards, which can meet the needs of future expansion; And the system has high reliability and convenient maintenance. The system has strong redundancy, fault tolerance, self diagnosis ability and technical support ability. It meets the needs of automatic control of the device in terms of function, stability and practicability

1. Advantages of the control system:

less investment, short supply cycle, and guaranteed spare parts

the control level is more diversified, which can meet the realization of multiple complex control schemes

it is conducive to centralized control and reduces the amount of system maintenance and the replacement of relevant spare parts

the system adopts redundancy, which greatly increases the safety and reliability of the system

make full use of the advantages of computers to diagnose and adjust the fault of field instruments

reduce the labor intensity of device operators and maintenance personnel, reduce staff and increase efficiency

2. New technical features of the control system

a. the system is an intelligent decentralized structure based on microprocessor, and the close combination of software and hardware makes the system give full play to its ability

b. The controller adopts redundant configuration and has high reliability. The failure of any component in the system will not affect the work of the whole system

c, the networking of the bottom connection, the full intelligence of the i/o module, the redundancy technology of hot backup, and the technical characteristics of reliable live plugging

d. The configuration software has five standard configuration tools: SFC, FBD, LD, st and FM. There are rich graphic libraries in the graphic tools, and the flow chart with friendly interface can be drawn soon

e, the system network is 100m redundant Fast Ethernet, which greatly accelerates the network speed and leaves sufficient room for future expansion and transformation

f. Fully open and advanced software and hardware technology is adopted, with flexible structure, safety and convenience, and simple maintenance

3. System configuration and human-computer interaction interface

the configuration software is Hollysys DCS system FOCS or Macs, the software platform is Chinese WIN2000, and the data exchange card is configured to release the data to the MIS to realize the sharing of compressor production parameters; Configure real-time information acquisition software on the computer of other posts or offices to understand the parameters and operation of the compressor. The configuration software mainly includes five subsystems: system configuration, database generation system, control scheme generation, graphic generation and report generation. In addition, there are historical library generation and shared library generation. The control system controls the operation of the compressor through the configuration software program of the lower computer; The upper computer configuration software flow chart picture is for people to wait for the solvent to evaporate completely and talk to the machine. The compressor operates according to the program to realize alarm interlocking. Once an alarm occurs, the computer interface will pop up an alarm screen to remind the operator to deal with the production situation in time to ensure the safe operation of production. The main functions of the control system: data acquisition and processing, process operation control and supervision management, operation screen display and alarm display, historical data storage function, equipment and status monitoring, program control, report printing, and implementation of emergency shutdown logic

2.3 selection of control system and instrument

in order to ensure the continuous, efficient and reliable operation of the compressor, the DCS system developed by Beijing Hollysys electrolytic lithium copper foil production expansion Co., Ltd. is selected as the control system. Because the compressor device operates with relatively large vibration and has high requirements for temperature and pressure, therefore, The instrument adopts armored integrated temperature transmitter and pressure transmitter with good anti vibration performance. The combination of imported alarm setter and relay is used to control the start and stop of the compressor. At the same time, the alarm signal is introduced into the computer control system to give audible and visual alarm and alarm bounce diagram in time

the alarm setter adopts the multi-channel output alarm output controller of the United States, which has the advantages of reliable operation, small maintenance and long operation time

3. Hardware design of control system

3.1. Hardware configuration

the main components of the control system of the compressor device: 2 servers (also known as control station, redundant configuration), 2 operator stations (one of which is also used as engineer station), field control station, communication station, and 1 printer

see the following figure for the network diagram of the system:

3.2. Alarm setter

this is the success of this compressor automation transformation. The alarm setter adopts the multi-channel output alarm controller of the United States. The device adopts the latest digital technology and microprocessor to alarm the signals from the field, which can be in two forms: single channel and double channel, and can output analog signals at the same time. There are self diagnostic indicators and output indicators on the alarm setter panel to monitor the working status of each channel at any time. The equipment is of modular design, reliable operation and small maintenance

the interlock shutdown control of the compressor is very important. Replace the electric II instrument of the original electrical control cabinet with an alarm setter, change it to low voltage (24V) control, and add a 24V relay in the new electrical control cabinet to control the operation of the compressor; The analog output of the alarm setter can not only ensure the signal acquisition, but also complete the alarm protection of the compressor. Under normal circumstances, once the compressor runs, it does not require shutdown. The alarm setter can control the operation of the compressor without stopping the machine when the computer fails or the system needs to be maintained. In this way, even when the automatic control system or computer stops running, the compressor can operate normally, reducing the compressor shutdown time

alarm setting control loop diagram is as follows:

4. Application effect and analysis of the system

after the compressor control of Hekou Oil production plant combined station, such as the initial station and Dabei station, is transformed by DCs, the compressor operates stably, the labor intensity of workers is low, the system works stably and reliably, and the real-time data collection, calculation and statistics greatly improve the timeliness and accuracy of compressor fault handling, and improve the work efficiency and management level. At the same time, the compressor DCS is a self-contained system, which can be controlled separately and connected to the large system of the combined station, providing a reliable basis for the automation transformation of the combined station

5. Conclusion

the efficient treatment of crude oil resources by the compressor unit not only saves resources, but also minimizes the pollution to the atmospheric environment, achieving the coordination and unity of social benefits, economic benefits and environmental benefits. After adopting DCS, with the improvement of product quality, the profit space of the enterprise has been greatly expanded, the market competitiveness of the enterprise has been further enhanced, and the technology and management of the enterprise have been promoted to a new height. The advantage of DCS control system is that it can flexibly and easily realize a variety of control schemes. The application of DCS system in the production process of compressor is the inevitable trend of the development of oilfield stability system. With the continuous development and improvement of automation technology, the cost is greatly reduced and the reliability is continuously improved. The compressor is controlled by DCS control system, which can realize the fast, accurate, stable and reliable operation in the production process, and achieve the purpose of improving efficiency and saving energy. (end)

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