| In recent vears,China's environmental protection has been developed by leaps and bounds, both technical theory and process equipment have greatly improved,but there is still a certain gap to compare the sewage disposal automatic-control system with the developed countries'.At present,the use of sequence batch reactor(Sequencing Batch Reactor referred to as the SBR method) to deal with industrial waste water which has a lot of changes in intermittent emissions of water quality and quantity,has achieved great success and was widely used.SBR sewage disposal process with characteristics of the multi-variable process,strong non-linear,serious uncertainties, difficulties in modeling and with which the key sewage water quality parameters can not be on-line measurement,control objectives can not be directly stated by process parameters,is a typical complex process.Fieldbus connection is a digital,two-way transmission,multi-branch-structure communications network which connect intelligent on-site equipment and automation systems.It is a high-degree intergrated product combining computer technology,communications technology and control technology,and is an open and distributed new model.Fieldbus is one of the hot spots in the development of automation technology field.This paper analyzes the characteristics of Fieidbus.From the type of PROFIBUS,the main characteristics,the principles of communication,transfer technology etc.,PROFIBUS communication technologies are discussed.Through study to the SBR sewage disposal proces sand the characteristics,put fieldbus technology into the sewage disposal process,and set up "Fieldbus-based SBR's automatic control system for sewage disposal." Design a sewage disposal plant control system map and plans of PROFIBUS network configuration.The difficulty of sewage disposal process - sewage aeration process control and nitrogen removal process control strategy has been studied,with fuzzy control strategy,it can more accurately reflect changes in water quality, reasonably control the amount of aeration,saving operation Costs.The automatic control system for sewage disposal based on fieidbus PORFIBUS designed in the paper,uses foreign advanced PROFIBUS fieldbus technology,to achieve a upper-position as the control of the work control machine IPC,a sewage pumping station PLC,the process of aeration PLC,sludge PLC Systems to take the communication to initiatives between,as well as to achieve the communication between the above-mentioned initiatives and the soft starter standing as a follower of the sewage pumping station,the inverter in the process of aeration,smart sensors in application of technology and external I/O devices. |
