炉管注汽量突增对焦化加热炉的影响及对策

Influence of sudden increasing of steam injection flow rate on coking furnace operation and the compensation method

延迟焦化加热炉是延迟焦化装置安全、长周期运行的关键设备。某炼厂焦化炉注蒸汽控制系统不能正常运行,注汽量突增造成炉管出口温度大的反向响应。当在PID自动控制或手动操作处理不及时、不适当时,将产生大的超温,加速炉管结焦．影响焦化炉安全平稳运行。本文分析了原因,提出了根据蒸汽注入量、进料量和进料压力对蒸汽量突增进行工况检测的方法。在此基础上,实现了对注汽量突增的专家规则控制。现场运行结果表明,避免了炉出口温度的大幅超温,达到甚至超过了熟练操作工操作的水平。

Coking furnace performance is critical to the safety and long period running of delayed coking unit. The steam injection system is subject to sudden steam increasing in a refinery coker unit. The response of the outlet temperature to the sudden steam increasing is a large inverse response. When under PID control or not handled properly in manual control, the outlet temperature has a large deviation above its normal value, which results in high coking rate in furnace tubes and affects the safety and long period running of the whole unit. By analyzing the operating data, a rule based monitoring method that combines the information of steam, feed flow rate and feed pressure is proposed to judge the event of sudden steam increasing. Then an expert control strategy simulating the skilled operator is developed. The main purpose is to prevent the temperature from violating the upper limit. Field control results show that the monitoring and control methods are effective.