燃煤电厂脱硫供浆控制系统研究

为了稳定降低SO₂的排放浓度来满足超低排放要求,设计了一套新的脱硫供浆系统控制方案。首先DCS依据理论公式和CEMS实时数据计算实时理论供浆量,采用串级PID调节供浆流量和出口SO₂浓度。其次,增加超前预控系数对PID调节量进行增减干预。再次,以机组负荷和入口SO₂浓度两个重要指标作为前馈信号,实时调整供浆流量。该厂实际运行结果表明:脱硫系统长期稳定运行,运行人员劳动强度降低,满足了节能减排要求,保障了企业经济效益。可得结论:此控制方案更好地满足了超低排放的要求,也非常适用于燃用高硫煤的脱硫系统。

Design and Test of Desulfurization Control Unit of Slurry for Coal-Fired Power Plant: An Experimental Study

A novel desulfurization control unit of coal slurry was developed for power plant to meet the environmental requirements on SO₂ emission.First, the control scheme was designed, based on the calculation in theory of distributed control system (DSC) and on data acquired in algorithm of continuous emission monitoring system (CEMD), and the cascade PID controllers regulated the flow-rate of slurry and SO₂ emission;second, the pre-control coefficient was increased to intervene PID regulation;and finally, the unit-load and SO₂ concentration served as the feed forward control signals to precisely adjust the coal-slurry flow-rate in real time.The newly-developed desulfurization control unit, installed in the coal-fired plant, has been continuously working pretty well since July, 2018.The results show that the novel control unit does an excellent job.We suggest that the new desulfurization control scheme be of some technological interest in burning of high sulfur coal.