Operating air circulating arrangement, comprises removing partial flow of pollutant-containing exhaust air from the air circulating arrangement, and oxidizing pollutant-containing exhaust air in the presence of catalyst

摘要

The method comprises receiving pollutants of circulating air (2) from a production process, where a fresh air is supplied to the pollutants of circulating air in an air circulating arrangement and an exhaust air is taken from the air circulating arrangement and is supplied to a waste air purification plant, removing a partial flow of the pollutant-containing exhaust air from the production process, and subjecting the pollutant-containing exhaust air to an oxidation state for oxidizing the pollutants. The oxidization step thermally takes place in the presence of catalyst. The method comprises receiving pollutants of circulating air (2) from a production process, where a fresh air is supplied to the pollutants of circulating air in an air circulating arrangement and an exhaust air is taken from the air circulating arrangement and is supplied to a waste air purification plant, removing a partial flow of the pollutant-containing exhaust air from the production process, and subjecting the pollutant-containing exhaust air to an oxidation state for oxidizing the pollutants. The oxidization step thermally takes place in the presence of catalyst, and is controlled based on measured parameters of oxygen contents and temperature and concentration of a combustible substance in introduction of the circulating air in the production process. The oxidation process is controlled over a desired temperature of the exhaust air in the air circulating arrangement. The air circulating arrangement comprises a first circulating circuit and a second circulating circuit. The partial flow of the pollutant-containing exhaust air is taken from the first circulating circuit or the second circulating circuit.