[Aerobic granulation for dimethyl phthalate biodegradation in a sequencing batch reactor].

This study investigated the feasibility of aerobic granulation for dimethyl phthalate (DMP) with the glucose as co-metabolism substrate in a sequencing batch reactor (SBR). Experimental results showed that aerobic granulation could be successfully realized in the reactor by controlling the organic loading and sludge settling time. The system could achieve average removal efficiencies of 92.3% for DMP and 90.6% for COD after 75 days operation. The DMP intermediate metabolites were determined and identified as monomethyl phthalate and phthalic acid. Degradation kinetics was well described by substrate inhibition pattern as Haldane equation, and the corresponding kinetic coefficients of V(max), K(s) and K(i) were 643.2 mg x (g x h)(-1), 171.0 mg x L(-1) and 337.5 mg x L(-1), respectively. Environmental scanning electronic microscope (ESEM) results showed that a clearly defined boundary with high porosity on the coarse surface. Many filamentous, coccoid and rod-shape bacteria were visible on the external surface of the granules.