6. Conclusions. Outlook

If the pollutant flows discharged are significant, and if their effects on human health and the environment need to be combated, a wide range of treatments is available. However, there are no universal processes. These technologies must therefore be carefully selected and implemented under optimum operating conditions for each specific gaseous discharge.

Research and development are still needed on existing processes to enhance their performance and make them more reliable, while minimizing operating and investment costs. Examples include: high-temperature filtration; new processes such as cold plasmas and photocatalysis, which have gone from emerging systems to interesting industrial developments; biological processes (biofilters and bioscrubbers), which have been studied and are of obvious interest for a number of applications involving very high flow rates and...