Optimization And Application Of PLC In Granular Deduster System

This thesis is based on Ningbo zhenhai refinery material dedusting system.After read a large number of domestic and foreign related references,the paper introduces general situation and the developing direction of the future of the Bag-type Dust removal system combined with the automation system when in the process of plastics production and processing at home and abroad.The overall design of the material removal system and the software and hardware configuration scheme of the system are described.Because it is the dust removal and collection treatment of the materials in the plastic production,taking into account the possibility of the dust burning or explosion,and the stability of the system,so during the system design,the hardware from the CPU to the power module are redundant design.The safety control system concept(SIS)is applied to the conventional PLC on the system control,not only ensures smooth operation of the system,but also ensure that the instrument or device in the entire system will return to the safety position under any critical logic or alarm trigger,it meets the first element of safe production largely.For the actual requirements of plastic production,we use the open-loop dust removal system of international famous company,the entire system includes: Dust removal system,dust collection system,etc.The control system is based on the German Siemens S7-300 PLC,it uses the engineer station and Touch screen as the monitoring operation platform.In a control cabinet,there are 412 redundant CPUs for data storage,processing,calculation,etc.Two local ET200 M control station are equipped with digital and analog modules to convert and collect the onsite instrument signals.CPU and control station for redundant communication via PROFIBUS-DP.A Siemens TP1200 touch screen is installed on the cabinet to facilitate the operator to visualize the screen,which also improves the efficiency of on-site production.In addition,due to need to exchange date with third-party equipment,we also equipped with CP341 communication card for Modbus RTU communication.The software uses STEP 7,to configure the logic and program,and uses the Portal V13 to draw the drawings.After the on-site and feedback,the whole system meets the expected requirements.Under the factors ensuring the safety,the operation is stable,the failure rate is low,the degree of visualization is high,and the upgrade and maintenance are more convenient.