资源描述
Applications as well as the importance of urban sewage treatment automatic control systemIn the case of increasing the economic level, peoples living standards have gradually improved, the attendant environmental problems have become increasingly prominent, especially domestic water and industrial pollution degree greatly improved, serious threat to the quality of life and health. With the global concern for environmental issues, energy efficiency and low carbon emissions economy is highly regarded in such an environment, water pollution problems become the focus of attention of the whole society. Meanwhile the international community and national environmental and other ecologically increasing investment and reform-related businesses fast forward, to solve the problem of water pollution measures and capacity has been greatly improved. On improve operational efficiency, reduce operating cost, through the introduction of intelligent control system, automatic control and remote monitoring, is an important solution, so in enterprise, scale and specialization trends, the introduction of related monitoring and control system is of great significance to enhance the overall operational effectiveness and quality.In the city sewage treatment plant automatic control system usually centralized monitoring approach, supplemented by decentralized control, the control room can be real-time monitoring of the entire operation of the sewage treatment plant, the specific production process is controlled by a separate place in a controlled manner.1.1 Features automatic control system Sewage treatment control system is more complex, involving physical quantity more, there are both analog digital; simultaneously control are also diverse, including real-time control and sequence control, as well as closed-loop control and open-loop control. Meanwhile, the ultimate control object is CODCr, BOD5, SS and pH, which is different from the general control system. To make the sewage treatment process qualified the above parameters, you need to deal with the operational status of the device, into mud and sludge quantity, the processing time for each process segment, dosage, etc. into the water and the displacement of integrated control, which greatly increases the complexity of the automatic control system. Currently, sewage treatment control system is controlled by a simple logic has been developed to a more decentralized control phase of development, which makes automatic control system for better openness, adaptability and economy, and scalability.Composition and structure of the automatic control system1.2 Modern sewage treatment control system is usually provided with the station and sub-station, terminus refers to the plant-level computer systems, sub-station refers to a field-level computer system, monitor the implementation of the two distribution modes. Plant-level computer systems mainly for the operation and management of sewage treatment plants for centralized monitoring, control and monitoring of all the whole plant process equipment primarily through the management of the PLC. Sub-station automatic control system includes the following: blower sub-stations, sludge return pump house station, blowers sub-station, primary processing sub-station, back to the house water pressure pump station, sludge dewatering stations with electronic station. Automatic control system using communication technology, automation technology, network technology, computer technology, graphics, database technology to build a comprehensive remote monitoring technology to automate.Hardware components including COD, pH, dissolved oxygen and other sensors; acquisition control unit includes PLC and data acquisition module; central monitoring unit includes servers, there are some auxiliary equipment, such as monitors and printers. Constitute a self-developed software, including software, there are mainstream INTOUCH, FIX, WIZCON, KINGVIEW so on. Domestic automation systems are basically developed to run on Windows or NT, and Windows NT for the database engine on the usually SQLServer, MySQL, etc.1.3 features automatic control systemSewage treatment control system features include: automatic control of the production process, real-time online monitoring, fault alarm, interlock protection, automatic generation of reports. These features can improve the efficiency of wastewater treatment plants, improve enterprise management level and labor productivity, and ensure the normal operation of equipment, reduce labor intensity.(1) On-line monitoring of online monitoring function is an important function of the automatic control system, with the function of dynamic flow chart can be displayed on a computer screen in the control room, while operating status of field devices, some of the important process parameters changes and instrumentation monitoring data, etc. can also be clearly displayed on the sub-station interface. You can easily use the mouse and keyboard on the system to intervene in accordance with the operating state of the device.(2) Real-time management to maintain the pipeline status parameter display, the full range of process flow diagram, convenient system. And can be recorded in real time during the operation, the operating behavior history database stored in chronological order, so well documented, responsibility to the people.(3) Control mode selection by the first stage of the sewage treatment plant control center for centralized monitoring, the second stage by the sub-station PLC control device for each operation manual or automatic selection in the control system can be completed. Meanwhile, the manual mode of operation should be used as a supplement to the automatic control mode.(4) There is equipment failure alarm processing, the first pre-set command will be the initial treatment failure, and the system will display the alarm screen to prompt the operator to handle the fault. Alarm window is divided into two parts: the current alarms and alarm history. The current alarm will indicate the existence of an alarm, the alarm has been processed disappeared and its associated alarm message will disappear from the current alarm; historical alarm not only indicate the existence of an alarm and the alarm to get processed its associated display and alarm information can still be query.2 ConclusionAutomatic control system compared with traditional manual control, greatly improving the sewage treatment automation and management level, but also greatly improve the quality of sewage treatment, reducing the emission of harmful substances produced good economic and social benefits. Because of automation technology in wastewater treatment started relatively late, our Western developed countries in this regard and there is still a large gap between the lack of independent research and development embodied in the control system, the lower the quality of the core production equipment and precision instruments, equipment failure rate higher ancillary aspects of the interface problem of domestic and foreign equipment and other equipment. So we want to increase R & D investment in this area, in order to narrow the gap with imported world advanced level.
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