CONTROL UNIT AND CONTROL METHOD OF DENITRIFICATION DEVICE AND DENITRIFICATION DEVICE PROVIDED WITH THE SAME

摘要

PROBLEM TO BE SOLVED: To control an appropriate ammonia injection amount.SOLUTION: A control unit 10 of a denitrification device 8 removes nitrogen oxide (NOx) in combustion exhaust by injecting a reducing agent containing ammonia (NH). The control unit 10 comprises: a calculation section 11 which calculates an amount of ammonia (NH) to be injected on the basis of amounts of nitrogen dioxide (NO) before denitrification reaction and formaldehyde (HCHO) in the combustion exhaust flowing into the denitrification device 8; and an injection control section 12 which injects the amount of the ammonia calculated by the calculation section 11. The calculation section 11 estimates the amount of the nitrogen dioxide (NO) on the basis of the amount of nitrogen monoxide (NO) estimated from a combustion load command value of a gas turbine 4 installed at an upstream side of the denitrification device 8, and calculates the amount of the ammonia (NH) on the basis of the estimated amount of the nitrogen dioxide (NO).