Exhaust air purification system against high hydrogen sulfide values

The exhaust air is sucked in with two centrifugal fans each. To separate any condensing moisture, the exhaust air first enters the droplet separator. In order to prevent the exhaust air from falling below the dew point even under unfavorable weather conditions, an air heater is connected downstream of the fan. The hydrogen sulfide is further purified in the following air filters: Two strands are operated, each with two filter containers piped in series. With help of electrochemical sensors, the contents of hydrogen sulfide in the exhaust air are monitored in raw gas after the first activated carbon filter and in the clean gas. In the event of malfunctions or extraordinary deviations from the set limit values, an alarm signal is output via contact to the control room of the wastewater treatment plant. At the Schönerlinde site, there are two almost identical exhaust air purification systems.