Design And Implementation Of White Water Recovery System In Paper Mill Based On DCS

Paper making is one of the four major inventions in China and has a long history.With the improvement of the quality of paper in modern production and life,the equipment of paper mill is developing towards high speed,large scale and high efficiency.This also puts forward higher requirements for the control system of paper mill.When more and more control devices and equipments become more and more complex,the traditional industrial control system can not meet the requirements of high-speed,stable and automated modern production.In order to meet this requirement,this paper introduces a DCS system based on the core of SIEMENS PCS7 platform.DCS system is a distributed control system with decentralized control functions,a centralized display operation,an autonomous and comprehensive coordination.The most important feature of DCS is the flexible configuration of various control and operation modules,which can realize diversified control strategies to meet the needs of different situations,making it more simpler to implement the unit combinatorial instrument.This paper will mainly introduce the DCS system based on SIEMENS PCS7 platform.Based on process automation,this system completes a set of sensors,actuators,controllers and host computers,and forms a complete TIA(fully integrated automation)architecture from bottom to top.The paper industry has the characteristics of large amount of water consumption and large waste water pollution in the process of paper making.From the point of view of saving resources and protect the environment,take effective measures to recycle and reuse of white water in plant,has long been of concern.Some advanced technologies of the country has done a lot of research in this area,China’s paper industry due to the urgency of environmental protection in this area has also been considerable development.The white water recovery system realized by polydisc is used to process the white water used in the workshop,so as to recover the fiber and make the water circulate in the workshop,which greatly reduces the water consumption and wastewater discharge.Aiming at the specific control demand of white water recovery system,this paper introduces the design idea and implementation details of DCS system for papermaking plant white water recovery system.Using the PCS7 platform to complete the PLC station and slave station(I/O station),ET engineer station,Dingshi communication module and other related equipment of the hardware configuration,design and construction of the corresponding PROFIBUS and Ethernet network configuration.Control strategy based on proportional control,PID control,cascade control and so on,application of CFC programming language to realize process control of white water recovery system;Using WINCC and MCGS software to design rich man-machine interaction pages to achieve the purpose of centralized operation and display,and introduce the methods and steps of simplifying picture configuration through the application of SIEMENS APL library.Finally,the debugging process and the application effect of the design of the white water recovery system are explained and studied in detail,and the control process and process flow are optimized according to the conditions and effects of the field application,so that the system can achieve the best work effect.