Abstract: Data on a secular change of each denitration catalyst is managed based on data obtained by a periodic maintenance and a daily management. Management of a secular change and prediction on performance variations that occur until a next periodic check is performed. It is determined whether the denitration catalyst is deteriorated such that an exhaust-gas denitration system cannot maintain its performance. When the denitration catalyst is deteriorated, regeneration, replacement, or addition of the denitration catalyst is performed, and the denitration catalyst is altered as necessary. When the denitration catalyst is usable, the denitration catalyst is not replaced nor regenerated.

Abstract: Data on a secular change of each denitration catalyst is managed based on data obtained by a periodic maintenance and a daily management. Management of a secular change and prediction on performance variations that occur until a next periodic check is performed. It is determined whether the denitration catalyst is deteriorated such that an exhaust-gas denitration system cannot maintain its performance. When the denitration catalyst is deteriorated, regeneration, replacement, or addition of the denitration catalyst is performed, and the denitration catalyst is altered as necessary. When the denitration catalyst is usable, the denitration catalyst is not replaced nor regenerated.

Abstract: Data on a secular change of each denitration catalyst is managed based on data obtained by a periodic maintenance and a daily management. Management of a secular change and prediction on performance variations that occur until a next periodic check is performed. It is determined whether the denitration catalyst is deteriorated such that an exhaust-gas denitration system cannot maintain its performance. When the denitration catalyst is deteriorated, regeneration, replacement, or addition of the denitration catalyst is performed, and the denitration catalyst is altered as necessary. When the denitration catalyst is usable, the denitration catalyst is not replaced nor regenerated.

Abstract: To provide a method for recovering performance of a discharge gas processing apparatus, the method being capable of recovering NOx removal performance of a deteriorated NOx removal catalyst without replacing the deteriorated NOx removal catalyst with a new catalyst and without adding a new catalyst. After a honeycomb catalyst 1 having gas conduits for feeding a gas to be treated has been placed and used in a discharge gas conduit of a discharge gas processing apparatus 10, the honeycomb catalyst 1 is rearranged such that a portion of the honeycomb catalyst 1—the portion being on the upstream side in terms of the flow of the gas to be treated and extending to cover a predetermined range is transferred from the inlet side of the discharge gas conduit.

Abstract: To provide a method for recovering performance of a discharge gas processing apparatus, the method being capable of recovering NOx removal performance of a deteriorated NOx removal catalyst without replacing the deteriorated NOx removal catalyst with a new catalyst and without adding a new catalyst. After a honeycomb catalyst 1 having gas conduits for feeding a gas to be treated has been placed and used in a discharge gas conduit of a discharge gas processing apparatus 10, the honeycomb catalyst 1 is rearranged such that a portion of the honeycomb catalyst 1—the portion being on the upstream side in terms of the flow of the gas to be treated and extending to cover a predetermined range is transferred from the inlet side of the discharge gas conduit.

Abstract: Secular change data on each unit of denitration catalysts (101) is managed based on data obtained by a periodic maintenance management (step S110) and a daily management (step S120), and management of a secular change and a performance variation prediction until a next periodic check is performed (step S130). It is determined whether a deterioration of the denitration catalyst (101) reaches a level at which a performance of an exhaust-gas denitration system (100) cannot be maintained (step S140). If it is determined that the deterioration is positive (“deteriorated” at step S140), then a regeneration, a replacement, or an addition of the denitration catalyst (101) is performed (steps S150, 160, and 170), the denitration catalyst is altered if necessary (step S180), and the denitration catalyst (101) is not replaced or regenerated (step S190) if it is recognized that the catalyst is usable (“usable” at step S140).