煤气混合加压站的过程控制技术

Process Control Technology for a Gas Mixing and Boosting Station

煤气混合和加压是钢铁企业副产煤气输配系统的关键环节之一,其过程控制直接关系到煤气供应品质。介绍了与宝钢宽厚板工程配套的9号煤气混合加压站,其技术特色在于:以压力—流量比值双闭环为主进行煤气混合控制,通过热值修正提高调节精度,采取分程控制扩大可调比;使用回流阀和入口阀联合调节的方式控制机后压力并防止喘振;以PLC结合现场总线技术进行控制系统组态。还对系统运行效果和存在问题进行了分析和探讨。

Gas mixing and boosting is a critical link of a steel maker＇ s by-product gas transport and distribution system. Its process control directly concerns the gas supply quality. The No. 9 gas mixing and boosting station setup for Baosteel Heavy Plate Plant is introduced. The main features of this station are as follows： The gas mixing control with priority is a dual-close-control both in pressure and flow ratio; the control precision is increased by means of calorie value revision; the stepcontrol increases the adjustable ratio; the compound control of back-flow valves and inlet valves has been used to control the outlet pressure of boosters and to prevent surge. The control system configuration is based on the PLC and site-bus control mode. In addition, the system＇ s running effect and the existing problems are analyzed and discussed.