Anti-surge Control System Design Optimization And DCS Implementation Of Nitrogen Compressor

With the increasing of the industrial nitrogen's applications in metal smelting,chemical industry,petroleum,coal chemical,mechanical processing and other fields,the anti-surge control for the nitrogen compressor,which is the key equipment in the nitrogen industry,is becoming more and more important.A major problem in the nitrogen industry is how to control the nitrogen compressor to make it more stable,efficient,energy saving,environmental.This paper takes the anti-surge control of the nitrogen compressor for 4#6000 air separation unit of Petrochina LANZHOU Petrochemical Company as the research background,and considers the main problems in the existing anti-surge control methods as a starting point.In this paper,causes of the surge of centrifugal compressor is analyzed,the main methods of compressor anti-surge control is summarized,and then the anti-surge control scheme of this unit is designed based on the surge curve equation computation of the 4#6000 air separation unit of the nitrogen compressor with a detailed comparison of the existing several control methods.The optimal anti-surge control algorithm is proposed by using classification progressive approach according to the determined decomposition parameters,and then the nitrogen compressor anti-surge control block diagram is given.By comparing with the traditional control mode,surge control by traditional control anti-surge valve is changed to the control entrance guide vane mode.Moreover,further analysis on the problems of the anti-surge operation is also conducted,and the logic of compressor safety is introduced.The Yokogawa CS-3000 DCS system is used to realize the anti-surge control,the control effect is verified by the actual operation and the direction of optimization in the next step is put forward.This paper makes great contributions to the anti-surge control design,DCS programming configuration and operation control for units.