Control of Slurry PH Value Based on Intermittent Pulse Method

In the wet desulfurization process, the control of slurry PH value in the absorption tower shows obvious non-linear and large lag characteristics. Therefore, it is difficult to achieve accurate control of the slurry PH value by conventional engineering control means. The intermittent pulse method proposed in this paper can not only realize the timing and quantitative control of the slurry volume, eliminate the large lag problem of slurry PH, but also eliminate the nonlinear problem of slurry PH control caused by the slurry supply equipment in the process of quantitative slurry delivery. The method is applied to the control of slurry PH in the absorption tower of a 600MW coal-fired power plant wet desulfurization system. The actual operation results show that under the premise that the slurry PH has room for upward adjustment and the outlet SO2 emission meets the standard, this method can better achieve the control accuracy of slurry PH within ±0.02 error range and reduce the loss of slurry, which reflects the practicality and economy of the method.