普光气田酸气加热炉智能控制系统的构建与优化

Building and optimizing an intelligent control system of a sour gas heating furnace in the Puguang Gas Field,Sichuan Basin

天然气加热炉广泛应用于天然气集输系统中,中国石化开发的四川盆地普光气田现有的加热炉系统无法实现流量和压力的自动控制,严重影响了该气田的生产运行效率。为此,分析了酸气加热炉的工艺流程及其特点,在此基础上构建了酸气加热炉的智能控制系统,并针对其不足进行了一系列优化:①二级节流阀开度流量关系曲线的线性优化;②偏差—控制量关系的优化;③偏差积分—控制量关系的优化;④流量压力延时控制优化;⑤采用多参数综合控制算法,使被控流量压力更快速进入稳态,达到新的设定值;⑥增加了智能识别和处理模块。优化后的酸气加热炉智能控制系统克服了原来PID控制系统的功能缺陷,实现了产出酸气流量、压力的稳定控制,为该气田的安全生产开发提供了技术保障。同时,该系统充分发挥计算机、PLC等智能化、数字化设备的优势,可以方便地通过计算机操作完成对全气田各井酸气自动调产、调压工作,为数字化气田建设提供了技术支持。

A natural gas heating furnace has been widely applied in natural gas gathering and transportation system in fields. However, the existing heating furnace system failed to achieve the automatic control of flow rate and pressure in the Sinopec Puguang Gas Field, Sichuan Basin, severely influencing the operation efficiency. In view of this, through the analysis of the flow process and char acteristics of a sour gas heating furnace in this field, an intelligent control system was built and was further optimized in many ways： the linear optimization of the valve opening vs flow rate of FVC flow control valve）, the optimization of deviation vs controlled variable, the optimization of deviation integral vs controlled variable, the optimization of delay time controlling of flow rate and pressure, the optimization of muhivariable proportional-integral-derivative （PID） controllers （as a result, the controlled flow rate and pressure will rapidly come to the steady state of reaching up to a newly set value）, and the addition of an intelligent recognition and processing module. The optimized intelligent control system for the sour gas heating furnace remedies the defect of the former PID controller to achieve the steady control of sour gas flow rate and pressure, providing robust technological support for the safe devel opment and production of the gas field. Besides, with such intelligent and digitalized equipments as computers, programmable logic controller （PLC）, etc. brought into full use, this optimized intelligent control system can help automatically control and adjust the well pro- duction and pressure of each sour gas well all over the field, providing technological support for the construction of a digitalized gas field.