Wastewater treatment photochemical AOPs

The most important water treatment technologies are summarized in Fig. 5-6. Depending on the source and on the water quahty, either mechanical, biological, physical, thermal, or chemical processes or their combinations may be applied. Photochemical AOPs and AOTs are subordinated to chemical processes, mainly because the current technological versions of photochemical wastewater remediation are dependent on the addition of auxihary oxidants, such as hydrogen peroxide, ozone or special catalysts such as titanium dioxide. Photochemical AOPs are attractive alternatives to non-destructive physical water treatment processes, for example adsorption, air stripping or desorption and membrane processes. The last merely transport contaminants from one phase to another, whereas the former are able to minerahze organic water contaminants (cf. Chapter 1). 

Solar photocatalytic degradation of water contaminants with titania and photo-Fenton catalysts has been carried out on a pilot-plant scale at the solar photochemical facilities of the Plataforma Solar de Almeria (PSA) in Spain, and show how solar photocatalysis is likely to become important within the next few decades in wastewater treatment and development of new AOP technologies [93, 94]. 

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