Automatic Control Of Sludge Centrifugal Dewatering System In Urban Sewage Treatment Plant

With the increasing awareness of environmental protection in our country,especially the continuous attention to water environmental protection.More and more urban sewage treatment plants have been built,modern sewage treatment technology has been continuously improved and developed,and the operating requirements of sewage treatment plants have become higher and higher.This has put forward higher requirements for the degree of automation of sewage treatment plants.The development trend of urban sewage treatment plants is highly automated control,and eventually the production and operation are less personified or even unmanned.The process of sludge centrifugal dehydration system in sewage treatment plant is introduced in detail.Based on the background and requirements of the project,the system requirement of sewage treatment plant is put forward.In this paper,the operation principle of sewage treatment process,sludge centrifugal dehydration process and centrifuge dewatering machine are studied.Based on an in-depth understanding of the automatic control of urban sewage treatment plants,according to the actual needs of Western water plants,the modular design of sludge centrifugal dehydration system was carried out,and the control methods of each subsystem of sludge centrifugal dehydration system were studied in detail.The molecular system module of automatic control is designed based on the characteristics of equipment,instruments and sensors involved in the process of sludge centrifugal dehydration.In the end,the sludge centrifugal dehydration system was designed into six subsystem modules such as additive,feed,centrifuge,sludge transport,and centrifuge backwash.The control object of sludge centrifugaldehydration system is introduced in detail,the connection scheme between PLC and inverter is determined,and the communication protocol of this design is Modbus protocol,and the communication control scheme between PLC and inverter under this protocol is determined.Based on the modular design of sludge dehydration system,using Siemens STEP7-Micro/WIN programming software,combined with Modbus master station protocol library,analog proportional conversion library and WD instruction guide,the automatic control of sludge centrifugal dehydration system is achieved by designing PLC program..Through the operation of PLC automatic control scheme of sludge centrifugal dehydration system designed in this paper,the operation effect reaches the author's design expectation,can meet the actual work demand of sludge centrifugal dehydration system of Western sewage treatment plant,and realizes the automatic control of sludge centrifugal dehydration treatment of sewage treatment plant.Finally,the sludge dehydration of the Western sewage treatment plant can be operated unsupervised.