6. Conclusion – some trends

Due to the complex mixtures of pollutants present in gases and flue gases at highly variable concentrations, their reduction requires a range of specific processes generally positioned in the treatment chain. Increasingly stringent legislation and public concerns relayed by the media mean that pollutants emitted in flue gases must be better controlled. So, while good industrial practices and the introduction of cleaner systems are obvious, specific emission treatment processes are also necessary. For this set of approaches, a few forward-looking proposals can be formulated.

To further increase filtration efficiencies, and therefore easier control of particulate levels in flue gases, high-efficiency industrial filtration techniques at high temperatures and at an acceptable cost still need to be improved.

Processes need to be intensified and/or...