The Design And Development Of A Sewage Treatment System For Pharmaceutical Factory

These years,with the rapid development of chemical industry,the pollution of waterbody due to the discharge of chemical wastewater becomes more and more serious.Currently,more than 5000 pharmaceutical enterprises can produce 10000 kinds of medicament,the total output is about millons of tons per year.According to statistics,the pharmaceutical waste water discharge amount is 0.25Gt,but the result of the treatments were however unappreciable.Sewage treated before recycling is a strategic choice.There is a lot of characteristics of the production process of sewage treatment,such as the large temperature difference,the water quality and quantity changes a lot.In order to meet the requirements of production and realize the integration of the management and and the control,we must adopt advanced process of production and strategy of control.Searching for an economical and effective system of sewage treatment has great significance.This issue takes the sewage treatment project of Lisheng Pharmaceutical Co.,Ltd.as the research background.Adopted Siemens S7-300 PLC,industrial Ethernet,Profibus-DP fieldbus and computer monitoring technology to realize sewage remote monitoring system.Use the dedicated programming software STEP7 of the Siemens PLC for completing the software prograrmming,then it will realize the start/stop,on/off control of the pumps and valves of the system;In the system we use the traditional PID control scheme to control the dissolved oxygen concetration.Use the optical fiber ring network technology for communications,then it will relize the data exchange between the PC and the next bit machine;Use the configuration software Kingview6.55 to simulate the process,alarm and report the system,manage the user security,etc.Wiring cable according to the sewage treatment plant location and the actual site,and set the control sub-station nearby to control the on-site instrument to save the expences.At the same time through the actual operating results of the scene,it has prove the control strategy is of feasible and outstanding.