离心泵变频调速与调节阀组合控制设计方案探讨

摘要

In petrochemical process, the adoption of variable frequency speed regulation can significantly reduce energy loss. But in most process piping system, the variable frequency speed regulation is usually set together with a flow control valve, and the realization process is much more complex. How to coordinate the relationship between them is pivotal to ensure the process to run safely, stably and efficiently, and maximally reduce energy loss. Five kinds of typical combination control schemes of variable frequency speed regulation and control valve of centrifugal pump and their implementation means are discussed. The proposal of suitable situation, control schemes, and switching among different operation conditions are put forward. It is concluded by analysis that variable frequency speed regulation can be easily accomplished in the scenario of single fluid, and can be with split-range combination control with a flow control valve. In the scenario of two fluids, variable frequency speed regulation and control valves in each fluid can be used separately, but combination control of variable frequency speed regulation and control valve is not suitable. For more complex scenario, manual variable frequency speed regulation can be used.%石油化工过程控制中采用离心泵变频调速技术可显著减少能量的损失,但大多工艺管路系统中变频调速与调节阀节流控制并存,实现过程比较复杂,协调好它们的关系是保证生产装置安全、平稳、高效运行,实现最大化节能的关键.探讨了五种典型的离心泵变频调速与调节阀组合控制设计方案及其实现的方法,提出了变频调速控制的适宜场合、控制方案及各种工况的切换操作等建议.分析认为单路控制方案容易实现变频调速控制,并可与调节阀分程协调控制；两路分支控制方案可实现变频调速和分支调节阀独立控制,但不宜采用变频调速与调节阀分程协调控制；更复杂的控制方案,可采用手动变频调速控制.