Ozone-biological activated carbon as a pretreatment process for reverse osmosis brine treatment and recovery

Treatment of organics in reverse osmosis concentrate from a municipal wastewater reclamation plant: Feasibility test of advanced oxidation processes with/without pretreatment

“…Among them, O 3 treatment achieved the best DOC removal efficiency (21.7%) along with almost 90% of the color removed. Nevertheless, similar to other studies [11,12], this study found that increasing energy input, catalyst dose or reaction time could only marginally improve the DOC removal efficiency.…”

“…Some organic fractions present in the RO concentrates could be also O 3 -resistant [11,13]. Therefore, improving the efficiency of non-selective • OH oxidation towards the organics is essential to achieve high removal of DOC present in the RO concentrate.…”

“…In the past several years, several simple AOPs, such as photocatalytic oxidation (PCO), ozonation (O 3 ), sonolysis (US) and electrolytic oxidation, have been investigated for organics removal from the RO concentrates [9][10][11][12][13][14][15][16][17]. However, in most cases, these AOPs could only mineralize small fractions of the organics.…”

“…Coupling AOPs with other treatment technologies would be effective alternatives to achieve high organics removal efficiency. Lee et al [11] have reported that more than 90% of the organic present in the RO concentrate could be removed with a integrated ozonation-biological AC treatment. The O 3 pretreatment was demonstrated to be effective in increasing the biodegradability of RO concentrate, although it could only achieved 20-30% mineralization of the organics.…”

THMs precursor removal by an integrated process of ozonation and biological granular activated carbon for typical Northern China water

“…However, the ozone cannot mineralize organic carbon with a traditional water treatment dose (less than 4 mg L −1 ); thus, a high removal of the THMs precursor cannot be expected by simple ozonation. Ozone can cleave the unsaturated bonds in aromatic moieties that are found in NOM, which makes the organic molecules smaller, more oxidized, and more biodegradable; thus, refractory NOM transforms to the biodegradable form, i.e., biodegradable dissolved organic carbon (BDOC) [14][15][16][17][18]. BDOC that is produced by ozonation can be removed in subsequent biological treatments.…”