Abstract
Colour and non-biodegradable trace organics present in the treated wastewater from sewage treatment plants (STPs) can affect the options for disposal or recycling. Colour is sometimes a concern because its visual appearance affects public acceptance of using recycled water. In the present study, different Advanced Oxidation Processes (UV/O3, UV/TiO2 and UV/TiO2/O3) in laboratory scale systems were used to study the removal efficiencies of colour and trace organics from the treated effluent. The removal efficiencies of the processes were compared by the analysis of colour, A254 (the organics absorption at the wavelength of 254 nm), and total organic carbon (TOC). The effects of ozonation procedure and ozone dose were also investigated. The co-treatment of ozonation and photocatalytic oxidation increased TOC removal rate by nearly 50 % compared to the process in which ozonation was used as a pre-treatment for photocatalysis. This was due to the synergistic effects of photocatalysis and ozonation. The colour removal rate significantly increased when the O3 dose was increased. Apart from AOPs, adsorption methods using activated carbons were also investigated for colour removal from recycled water. TiO2 nanoparticles were loaded on the surface of the granular activated carbons (GAC). This allows the GAC to be regenerated by UV irradiation without the thermal treatment. The adsorption results using a fixed bed column were reported, and the regeneration potential of the activated GAC was also discussed.
| Original language | British English |
|---|---|
| Title of host publication | Sewage Treatment |
| Subtitle of host publication | Uses, Processes and Impact |
| Publisher | Nova Science Publishers, Inc. |
| Pages | 325-339 |
| Number of pages | 15 |
| ISBN (Print) | 9781606929599 |
| State | Published - 2009 |