CONTROL SYSTEM OF DESULFURIZATION AND DENITRIFICATION FOR SMOKE EXHAUST FACILITY

摘要

PURPOSE:To enable to automatically control desulfurization operation of a waste smoke, in desulfurizing the waste smoke, by a method wherein a signal of a SOx amount at a waste smoke outlet of the desulfurization apparatus is utilized as a control variable and a control signal of a waste smoke flow amount to the desulfurization apparatus as an operation output. CONSTITUTION:A flow meter F1 is provided at a point P1 where the waste smoke from a boiler is entered to the desulfurization apparatus, a concn. sensor S0 of SOx in a desulfurization pipe 3 and a sensor S2 at place P2 of an outlet pipe. Detection signals of the sensors S0-S2 and a signal of the flow meter F1 are applied to an operation apparatus 10 and the product of an operation signal Fs and a deviation Er with an objective set SOx from a controller 6 is measured in a multiplication circuit 11. From an S amount flowed into a discharge pipe 1 from an A point and an S amount flowed into the A point, a flow amount Fx is measured and, according to the resulting value, a waste gas inflow amount Fx to the waste smoke desulfurization apparatus 4 is controlled so as to adjust the operation signal Fs of the operation apparatus 10. Further, as the compensation control of the aforementioned control system, a cascade control wherein a SOx control system due to the discharge pipe 1 is a primary loop and an inflow amount control to the waste smoke desulfurization apparatus 4 is a secondary loop is carried out.