Sequencing batch airlift reactors (SBAR): a suitable technology for treatment and valorization of mineral oil wastewaters towards lipids production

Produced water (PW) and spent oil-based wastewaters are some of the largest mineral oil produced. Due to high toxicity hydrocarbons, several countries set stringent discharge limits its treatment is compulsory before discharge. In this work, biological coupled with production bacterial lipids demonstrated in sequential batch airlift reactors (SBAR). Two SBAR (2 L working volume) were used for PW lubricant-based wastewater (LW), inoculated Alcanivorax borkumensis SK2 (SBARAb+PW) Rhodococcus opacus B4 (SBARR.o+LW), respectively. A total petroleum hydrocarbon removal (TPH) efficiency up 96% 80% achieved SBARAb+PW SBARR.o+LW, Intracellular increased when lower TPH/N ratios higher feast stage duration applied (up 0.74 g g-1 cell dry weight (CDW)), whereas SBARR.o+LW was observed (0.94 CDW). Triacylglycerols (TAG) main intracellular lipid accumulated both operations, while wax ester (WE) only extracellularly SBARAb+PW.