JPH0548425B

PURPOSE:To continuously measure SO2-concn., by performing operation by utilizing the correlation of Ca-content and an SO2-gas converting ratio and the correlation of an exhaust gas temp. and SO2-gas permeability on the basis of the Ca-content in coal ash, the signal of SO2-concn. in exhaust gas and the temp. signal of the exhaust gas as input signals. CONSTITUTION:The Ca-content A in ash of coal burnt in a boiler 1, the SO2-concn. signal B at the inlet of the heat exchanger 6 for a desulfurization apparatus and the exhaust gas temp. signal C at the inlet of the heat exchanger 6 for the desulfurization apparatus are inputted to an operator comparator circuit 20. The correlation of the Ca- content in coal ash and an SO2-gas converting ratio and the correlation of the exhaust gas temp. and the SO2-gas permeability at the inlet of the heat exchanger for the desulfurization apparatus are stored in a memory circuit 21. The operator comparator circuit 20 compares the SO2-gas converting ratio and the SO2-gas permeability outputted from the memory circuit 21 with the above mentioned signals A, B, C to perform operation to generate the SO2-gas concn. signal at the inlet of the heat exchanger 6 for the desulforization apparatus and this signal is sent to an SO2-gas concn. display apparatus 22 where the SO2-gas concn. at the inlet of the heat exchanger 6 for the desulfurization apparatus is continuously displayed.