#achema2018 - While CO₂ capture from ambient air is a technology that has set minds on fire, the treatment of waste flue gas emissions from an industrial unit is equally crucial and critical. Duerr’s catalytic candle filter provides a compact and efficient arrangement for the removal of pollutants from waste flue gases.

The candle, cylindrical in shape, is constructed out of a suitable porous catalyst and is mounted in a vertical fashion. The flue gases obtained from various processes in a process unit are fed to the assembly from the bottom. As the gases rise upwards due to gravity, they are catalytically oxidised on the surface of the porous catalyst and convert to their completely oxidised counterparts. These treated flue gases then leave the candle from the top, only to be filled in by a new batch of waste emissions. The candle is enveloped in a suitably porous filter media in order to separate the particulates in the visible range.

The life span of the candle lasts between 3-5 years and is a function of the maintenance, the proportion of particulates in the flue gases and the amount of flue gases to be treated. The porosity of the catalyst facilities rapid diffusion and thus, enhances mass transfer. The catalytic candle filter provides a compact arrangement to achieve complete physical and chemical separation in a single unit, thereby scrubbing off the need of a stripper and an electrostatic precipitator as a separate arrangement.